Language：English   Publishing type：Research paper (scientific journal)  

Repository Public URL： https://hdl.handle.net/2324/7178539

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1021/acsaem.2c01437

Language：Others   Publishing type：Research paper (scientific journal)   Publisher：Japanese Journal of Applied Physics  

Hybrid halide perovskite research has recently been focused on thermoelectric energy harvesting due to the cost-effectiveness of the fabrication approach and to the ultra-low thermal conductivity. To achieve high performance, tuning of the electrical conductivity is a key parameter that is influenced by grain boundary scattering and charge carrier density. The fabrication process allows the tuning of these parameters. We report the use of anti-solvent to enhance the thermoelectric performance of lead-free hybrid halide perovskite (CH3NH3SnI3) thin films. Thin films with anti-solvent show higher connectivity in grains and higher Sn+4 oxidation states which result in the enhancement of the value of electrical conductivity. The thin films were prepared by a cost-effective wet process. Structural and chemical characterizations were performed using X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The values of electrical conductivity and the Seebeck coefficient were measured near room temperature. A high value of the power factor (1.55 μW m-1 K-2 at 320 K) was achieved for thin films treated with anti-solvent.

DOI： 10.35848/1347-4065/ac4adb

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Language：English   Publishing type：Research paper (scientific journal)  

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DOI： 10.1109/powermems54003.2021.9658403

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1063/5.0055581

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.icheatmasstransfer.2021.105404

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DOI： https://doi.org/10.1016/j.ceramint.2021.03.098

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DOI： https://doi.org/10.1016/j.ijheatmasstransfer.2021.121006

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DOI： https://doi.org/10.1016/j.expthermflusci.2020.110285

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.apsusc.2020.146454

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1016/j.ijheatmasstransfer.2020.119755

Language：English   Publishing type：Research paper (scientific journal)  

Uni-leg thermoelectric module comprised by coated hybridperovskite thin film

DOI： https://doi.org/10.1115/1.4047360

Language：English   Publishing type：Research paper (scientific journal)  

Top-down approach using supercritical carbon dioxide ball milling for producing sub-10 nm Bi2Te3 grains
We compare Bi2Te3 powders prepared by conventional ball milling to powders milled in supercritical carbon dioxide (scCO(2)). We demonstrate that scCO(2) milling overcomes size-reduction limitations reported for conventional milling. XRD and TEM reveal nanograins with smaller average sizes (< 10 nm) and narrower grain size distributions in the scCO(2) milled case. scCO(2) milling also preserves the crystallinity and shows less oxidation than conventional milling. This is the first report of Bi2Te3 with a sub-10 nm grain size whilst conserving high quality crystallinity, made using a top-down approach. Our study offers a route for developing unprecedentedly fine bulk nanostructured Bi2Te3-based thermoelectric materials.

DOI： 10.35848/1882-0786/ab91d2

Language：English   Publishing type：Research paper (scientific journal)  

DOI： https://doi.org/10.1107/S2052520620002383

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)  

Hybrid-Halide Perovskite Thin Film Growth for Thermoelectric Applications
Thermoelectric effect can convert thermal energy into electricity without any moving parts or vibrations in light or dark. These can be promising advantages to develop sustainable energy source for internet of things devices. In this regards, thin films of hybrid-halide perovskites, methylamonium tin iodide, were fabricated by spin coating technique on a glass substrate at different annealing times. Thin films were structurally and chemically characterized by x-ray diffraction pattern and a scanning electron microscope. Thermoelectric parameters were measured near room temperature. During optimization, thin films annealed for 5 min at 100°C shows the high performance with electrical conductivity 3.56 S/cm, Seebeck coefficient 66.03 μV/K and power factor of 1.55 μW/m K2 at 50°C. Thermoelectric performance from these hybrid-halide perovskite will help for further development of direct thermal energy harvesting devices near room temperature.

DOI： 10.1007/s11664-020-07958-6

Language：English   Publishing type：Research paper (scientific journal)  

Effect of Precursor Solution Aging on the Thermoelectric Performance of CsSnI3 Thin Film
ICT2019発表特集号

DOI： 10.1007/s11664-019-07846-8

Language：English   Publishing type：Research paper (scientific journal)  

Control of the pore size of honeycomb polymer film from micrometers to nanometers via substrate-temperature regulation and its application to photovoltaic and heat-resistant polymer films

DOI： 10.1088/1361-6528/ab4521

Language：English   Publishing type：Research paper (scientific journal)  

Interface engineering using Y2O3 scaffold to enhance the thermoelectric performance of CsSnI3 thin film
Solution processed Cesium Tin halide perovskites (CsSnI3) are inorganic crystal to be explored for thermoelectric applications. Here, we report a novel strategy using an inorganic Y2O3 scaffold to improve the thermoelectric performance. The additional Y2O3 influence the CsSnI3 crystal growth and favor more conducting behavior with intrinsic defects (Sn4+) formation. Therefore, the resulting solution processed composite film Y2O3/CsSnI3 show much improved electrical conductivity of ~310 S/cm as compared to ~98 S/cm of pristine CsSnI3 film. Under the influence of Y2O3, the resulting phonon scattering path was enhanced significantly due to formed defects/vacancy and reduced CsSnI3 crystal size, which showed a reduction in thermal conductivity from 0.74 W/mK to 0.28 W/mK. This work paves a new paradigm to improve the thermoelectric performance of solution based thermoelectric generator.

DOI： 10.1016/j.orgel.2019.105488

Language：English   Publishing type：Research paper (scientific journal)  

Porosity-tuned thermal conductivity in thermoelectric Al-doped ZnO thin films grown by mist-chemical vapor deposition

DOI： 10.1016/j.tsf.2019.06.010

Language：English   Publishing type：Research paper (scientific journal)  

Two-Dimensional Phonon Polariton Heat Transport
大学よりプレスリリース

DOI： 10.1021/acs.nanolett.9b02214

Language：English   Publishing type：Research paper (scientific journal)  

Growth of halide perovskites thin films for thermoelectric applications

DOI： 10.1557/adv.2019.279

Language：Japanese   Publishing type：Research paper (scientific journal)  

Measurement of Thermal Boundary Resistance of Organic-Inorganic Materials

Language：English   Publishing type：Research paper (scientific journal)  

Printed Thermoelectric Device

Language：English   Publishing type：Research paper (other academic)  

Experimental study of the in-plane thermal conductivity enhancement of suspended glass thin films due to long range surface phonon-polaritons

Language：English   Publishing type：Research paper (other academic)  

Interfacial thermal resistance between Bismuth Telluride and PEDOT:PSS

Language：English   Publishing type：Research paper (other academic)  

Printed Flexible Thermoelectric Device of the Organic/Inorganic composite
ICOT
International Conference on Organic and Hybrid Thermoelectrics

Language：English   Publishing type：Research paper (other academic)  

Normal Emittance of Metal Coated Silica Spheres Array

Language：English   Publishing type：Research paper (other academic)  

Experimental Investigation of the Enhanced Thermal Conductivity of Silica Suspended Thin Films due to Long-Range Surface Phonon-Polaritons

Language：English   Publishing type：Research paper (scientific journal)  

The influence of Y2O3 nanolayers on thermoelectric performance and structure of 2&#37; Al-doped ZnO (AZO) thin films has been studied. Multilayers based on five 50 nm thick AZO layers alternated with few nanometers thick Y2O3 layers were prepared by pulsed laser deposition on Al2O3 single crystals by alternate ablation of AZO target and Y2O3 target. The number of laser shots on Y2O3 target was maintained very low (5, 10 and 15 pulses in three separate experiments. The main phase (AZO) presents polycrystalline orientation and typical columnar growth not affected by the presence of Y2O3 nanolayers. The multilayer with 15 laser shots of Y2O3 showed best thermoelectric performance with electrical conductivity sigma = 48 S/cm and Seebeck coefficient S=-82 mu V/K, which estimate power factor (S-2.sigma) about 0.03 x 10(-3) W m(-1) K-2 at 600 K. The value of thermal conductivity (kappa) was found 10.03 W m(-1) K-1 at 300 K, which is one third of typical value previously reported for bulk AZO. The figure of merit, ZT = S-2 .sigma . T/kappa, is calculated 9.6 x 10(-4) at 600 K. These results demonstrated the feasibility of nanoengineered defects insertion for the depression of thermal conductivity.

DOI： 10.1166/jnn.2017.13717

Language：English   Publishing type：Research paper (other academic)  

In-plane Thermal Conductivity of Bismuth Telluride Thin Films

Language：English   Publishing type：Research paper (other academic)  

Experimental Detection of Enhanced Thermal Properties of Glass Thin Films due to Long Range Surface Phonon-Polaritons
Tranchant助教主担当

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Thermal Radiation of Spectrally Selective Solar Absorber Based on MOD Method

Language：English   Publishing type：Research paper (other academic)  

Pool Boiling CHF Enhanced with Superhydrophilic Micro/Nano Structures Fabricated by Thermal Spray and Chemical Oxidation
矢吹助教主担当

Language：English   Publishing type：Research paper (other academic)  

Experimental detection of the enhanced longitudinal propagation of surface phonon-polaritons on SiO2 thin films

Language：English   Publishing type：Research paper (other academic)  

2 omega and 3 omega thermal conductivity measurements for thin dielectric films

Language：English   Publishing type：Research paper (scientific journal)  

Thermal phonon transport in single-crystalline Si thin films with dog-leg shaped nanostructures was investigated. Thermal conductivities for the forward and backward directions were measured and compared at 5 and 295K by micro thermoreflectance. The Si thin film with dog-leg shaped nanostructures showed lower thermal conductivities than those of nanowires and two-dimensional phononic crystals with circular holes at the same surface-to-volume ratio. However, asymmetric thermal conductivity was not observed at small temperature gradient condition in spite of the highly asymmetric shape though the size of the pattern is within thermal phonon mean free path range. We conclude that strong temperature dependent thermal conductivity is required to observe the asymmetric thermal phonon conduction in monolithic materials with asymmetric nanostructures. (C) 2016 The Japan Society of Applied Physics

DOI： 10.7567/JJAP.55.085201

Language：English   Publishing type：Research paper (scientific journal)  

After more than three decades of molecular and carbon-based electronics, the creation of air-and thermally stable n-type materials remains a challenge in the development of future p/n junction devices such as solar cells and thermoelectric modules. Here a series of ordinary salts are reported such as sodium chloride (NaCl), sodium hydroxide (NaOH), and potassium hydroxide (KOH) with crown ethers as new doping reagents for converting single-walled carbon nanotubes to stable n-type materials. Thermoelectric analyses reveal that these new n-type single-walled carbon nanotubes display remarkable air stability even at 100 degrees C for more than 1 month. Their thermoelectric properties with a dimensionless fi gure-of-merit (ZT) of 0.1 make these new n-type single-walled carbon nanotubes a most promising candidate for future n-type carbon-based thermoelectric materials.

DOI： 10.1002/adfm.201600179

Language：English   Publishing type：Research paper (scientific journal)  

On-chip thermoelectric thin film modules containing 5 legs of n-type (Al0.02Zn0.98O) and 5 legs of p-type (Ca3Co4O9) were fabricated on Al2O3, SrTiO3 single crystal, and fused silica substrates by pulsed laser deposition technique. Performance of modules was evaluated using ad hoc customized system where the module was set vertically for temperature gradient. The maximum output power (P-max) was obtained on Al2O3 (0001) single crystal substrate with temperature difference (Delta T) = 230 degrees C (T-h = 300 degrees C): P-max = 29.9 pW. The value of maximum output power increases with increase of temperature difference (Delta T) These results are encouraging for the practical applications of thermoelectric oxide thin films. (C) 2016 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.enconman.2016.02.001

Language：English   Publishing type：Research paper (scientific journal)  

The influence of self-grown seed has been studied on thermoelectric performance of 2&#37; Al-doped ZnO(AZO) thin films. The thickness and orientation of c-axis domains in seed layer change on different substrates while other deposition conditions were kept unchanged for a comparable study. The changes occur because of the different nucleation process of thin film growth on substrate interface and the different lattice mismatch between AZO and substrate. Thin films are grown by pulsed laser deposition on single crystals (SrTiO3 (STO) and Al2O3) and cheap amorphous fused silica (FS) substrates at 400 degrees C. All thin films are c-axis oriented. The grains are highly connected and elongated in shape which leads to high thermoelectric properties. The thicker self-grown seed layer is found in thin film deposited on FS substrates which shows best performance: electrical conductivity sigma = 93 S/cm and Seebeck coefficient S = -203 mu V/K, which estimate power factor (S-2.sigma) about 0.37 x 10(-3) Wm(-1)K(-2) at 600 K. The value of thermal conductivity (kappa) was found lowest (4.89 Wm(-1)K(-1)) for thin film deposited on FS than the other thin films (6.9 Wm(-1)K(-1) on Al2O3 and 6.55 Wm(-1)K(-1) on STO) at 300 K. The figure of merit, ZT = S-2.sigma.T/kappa, is calculated 0.046 at 600 K, 5 times larger than the ZT of our previous reported bulk AZO, which is promising for practical applications of thermoelectric oxide thin films. (C) 2015 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.tsf.2015.09.060

Language：English   Publishing type：Research paper (other academic)  

Enhanced Figure of Merit of a Self-assembled Micro-porous Bismuth Telluride Thin Films

Language：English   Publishing type：Research paper (scientific journal)  

The microstructure of materials affects thermal and electrical transport as well as the physical properties. The effects of the microstructure on both thermal and electrical transport in silicon membranes with periodic microporous structures produced from silicon-on-insulator wafers using microfabrication processes were studied. The in-plane thermal and electrical conductivities of the Si membranes were measured simultaneously by using a self-heating method. The measured thermal conductivity was compared with the result from the periodically laser-heating method. The thermal and electrical conductivities were much lower in the porous membranes than in the non-porous membrane. The measured thermal conductivity was much lower than expected based on values determined using classical models. A significant phonon size effect was observed even in microsized structures, and the mean free path for phonons was very long. It was concluded that phonon transport is quasi-ballistic and electron transport is diffuse in microporous Si structures. It was suggested that the microstructure had a different effect on thermal and electrical transport.

DOI： 10.1007/s10765-014-1643-z

Language：English   Publishing type：Research paper (scientific journal)  

A two-step method that combines homogeneous electron beam (EB) irradiation and thermal annealing has been developed to enhance the thermoelectric properties of nanocrystalline bismuth selenium telluride thin films. The thin films, prepared using a flash evaporation method, were treated with EB irradiation in a N-2 atmosphere at room temperature and an acceleration voltage of 0.17 MeV. Thermal annealing was performed under Ar/H-2 (5&#37;) at 300 degrees C for 60 min. X-ray diffraction was used to determine that compositional phase separation between bismuth telluride and bismuth selenium telluride developed in the thin films exposed to higher EB doses and thermal annealing. We propose that the phase separation was induced by fluctuations in the distribution of selenium atoms after EB irradiation, followed by the migration of selenium atoms to more stable sites during thermal annealing. As a result, thin film crystallinity improved and mobility was significantly enhanced. This indicates that the phase separation resulting from the two-step method enhanced, rather than disturbed, the electron transport. Both the electrical conductivity and the Seebeck coefficient were improved following the two-step method. Consequently, the power factor of thin films that underwent the two-step method was enhanced to 20 times (from 0.96 to 21.0 mu W/(cmK(2)) that of the thin films treated with EB irradiation alone. (C) 2015 AIP Publishing LLC.

DOI： 10.1063/1.4928311

Language：English   Publishing type：Research paper (scientific journal)  

We have estimated the thermal conductivity of nanocrystalline bismuth telluride thin films using the differential 3 omega method, taking into account the thermal contact resistance (TCR) between the substrate and thin-film layers. The thin films were prepared on alumina substrates by radio-frequency (RF) magnetron sputtering at temperature of 200A degrees C. Film thickness varied between 0.8 mu m and 3.1 mu m. The structural properties of the films were analyzed using x-ray diffraction analysis. Their electrical conductivity, Seebeck coefficient, and power factor were evaluated. For measurement of thermal properties by the differential 3 omega method, SiO2 thin films were deposited onto the samples, to act as insulating layers. Thin aluminum wire was then patterned onto the SiO2 layer. The observed variations in temperature amplitude as a function of film thickness indicated that the TCR contribution was very small and could therefore be neglected when estimating the thermal conductivity of the thin films. The thermal conductivity of the nanocrystalline bismuth telluride thin films with thickness of 0.8 mu m and 2.1 mu m were determined to be 0.55 W/(m K) and 0.48 W/(m K), respectively.

DOI： 10.1007/s11664-015-3646-3

Language：English   Publishing type：Research paper (scientific journal)  

To investigate the effect of strain on bismuth telluride films, we applied different compressive and tensile strains to thin films by changing the bending radius of a flexible substrate so the strain ranged from -0.3&#37; (compressive) to +0.3&#37; (tensile). The structural properties of the strained thin films, composed of nanosized grains, were analyzed by x-ray diffraction and scanning electron microscopy. For all samples the main peak was the (015) diffraction peak; crystal orientation along the (015) growth direction was slightly enhanced by application of compressive strain. The thermoelectric properties of strained bismuth telluride thin films were evaluated by measurement of electrical conductivity, Seebeck coefficient, and power factor. The magnitude and direction of the applied strain did not significantly affect the power factor, because when the strain changed from compressive to tensile the electrical conductivity increased and the absolute Seebeck coefficient decreased.

DOI： 10.1007/s11664-014-3496-4

Language：English   Publishing type：Research paper (scientific journal)  

We have investigated the thermoelectric properties of 2&#37; Al-doped ZnO (AZO) thin films depending on the postdeposition cooling atmosphere [in oxygen pressure (AZO-O) or vacuum (AZO-V)]. Thin films were grown by pulsed laser deposition on sapphire () substrates at various deposition temperatures ( to ). All films were c-axis oriented. The electrical conductivity of AZO-V thin films was higher than that of AZO-O thin films across the whole temperature range from 300 K to 600 K, due to the optimal carrier concentration () of AZO-V samples. Furthermore, the thermoelectric performance of AZO-V films increased with the deposition temperature; for instance, the highest power factor of and dimensionless figure of merit of 0.07 at 600 K were found for AZO-V thin film deposited at .

DOI： 10.1007/s11664-014-3471-0

Language：English   Publishing type：Research paper (scientific journal)  

To investigate the effect of strain on specific heat, sound velocity and lattice thermal conductivity of nanocrystalline bismuth antimony telluride thin films, we performed both experimental study and modeling. The nanocrystalline thin films had mostly preferred crystal orientation along c-axis, and strains in the both directions of c-axis and a-b-axis. It was found that the thermal conductivity of nanocrystalline thin films decreased greatly as compared with that of bulk alloys. To gain insight into the thermal transport in the strained nanocrystalline thin films, we estimated the lattice thermal conductivity based on the phonon transport model of full distribution of mean free paths accounting for the effects of grain size and strain which was influenced to both the sound velocity and the specific heat. As a result, the lattice thermal conductivity was increased when the strain was shifted from compressive to tensile direction. We also confirmed that the strain was influenced by the lattice thermal conductivity but the reduction of the lattice thermal conductivity of thin films can be mainly attributed to the nano-size effect rather than the strain effect. Finally, it was found that the measured lattice thermal conductivities were in good agreement with modeling.

DOI： 10.1007/s11664-014-3518-2

Language：English   Publishing type：Research paper (other academic)  

We investigated effects of the submicron structured thermoelectric thin films and module on their performance. The output power of the submicron structured module was 1.5 times greater than that of a smooth structured module.

DOI： 10.1109/ICSJ.2014.7009640

Language：English   Publishing type：Research paper (scientific journal)  

The effects of homogeneous irradiation of electron beam (EB) on the crystal growth and thermoelectric properties of nanocrystalline bismuth selenium telluride thin films were investigated. The thin films were prepared using a flash evaporation method, after which EB irradiation was performed under N-2 at room temperature at an accelerated voltage of 0.17 MeV. SEM revealed that the untreated thin film was composed of a large quantity of rice-like nanostructures. With increasing the EB irradiation dose, a number of nanodots with diameters of less than 10 nm became visible on the surface of the rice-like nanostructures. The crystallinity and the crystal orientation were enhanced with increasing EB irradiation dose while the average crystal grain size remained almost the same size as that of the untreated thin film. In terms of thermoelectric properties, the mobility of the thin films was enhanced as the EB irradiation dose was increased while the carrier concentration was not greatly changed. As a result, both the electrical conductivity and the Seebeck coefficient were improved with increasing EB irradiation dose. Consequently, even though there is still room for further improvement, the power factor was enhanced around sevenfold (from 0.14 to 0.96 mu W/cm/K-2) by the EB irradiation treatment. (C) 2014 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2014.05.146

Language：English   Publishing type：Research paper (other academic)  

Thermal Rectifier by Using Semi-ballistic Transfer of Phonons in Asymmetric Liner Structures

Language：English   Publishing type：Research paper (other academic)  

Enhanced Emittance of a Silica Photonic Crystal

Language：English   Publishing type：Research paper (scientific journal)  

We investigated the effects of strain and grain size on the thermal transport of highly-oriented nanocrystalline bismuth antimony telluride thin films using both experimental studies and modeling. The fabricated thin films had preferred crystal orientation along the c-axis, average grain sizes of 30 < d < 100 nm, and strain of -0.8&#37; < epsilon < -1.4&#37; in the c-axis direction, whereas the strain in the a-b-axis direction was constant at 1.7&#37;. The thermal conductivities were measured to be 0.32 < k < 0.52 W/m/K using a 3 omega method at room temperature. To gain insight into the thermal transport in the strained nanocrystalline thin films, we estimated the lattice thermal conductivities from the measured thermal conductivities. We then calculated the lattice thermal conductivity using a simplified phonon transport model that accounts for the strain effect based on the Christoffel equation and uses Lennard-Jones potentials, and the grain size effect based on the full distribution of mean free paths. The theoretical calculations were in good agreement with our experimental results, and we conclude that the decrease of the lattice thermal conductivity of nanocrystalline thin films can be mainly attributed to the nano-size effect rather than the strain effect. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijheatmasstransfer.2014.04.048

Language：English   Publishing type：Research paper (scientific journal)  

The effects of homogenous electron beam (EB) irradiation on the crystal growth and thermoelectric properties of n-type Bi-Se-Te and p-type Bi-Sb-Te thin films were investigated. Both types of thin films were prepared by flash evaporation, after which homogeneous EB irradiation was performed at an acceleration voltage of 0.17MeV. For the n-type thin films, nanodots with a diameter of less than 10nm were observed on the surface of rice-like nanostructures, and crystallization and crystal orientation were improved by EB irradiation. The resulting enhancement of mobility led to increased electrical conductivity and thermoelectric power factor for the n-type thin films. In contrast, the crystallization and crystal orientation of the p-type thin films were not influenced by EB irradiation. The carrier concentration increased and mobility decreased with increased EB irradiation dose, possibly because of the generation of defects. As a result, the thermoelectric power factor of p-type thin films was not improved by EB irradiation. The different crystallization behavior of the n-type and p-type thin films is attributed to atomic rearrangement during EB irradiation. Selenium in the n-type thin films is more likely to undergo atomic rearrangement than the other atoms present, so only the crystallinity of the n-type Bi-Se-Te thin films was enhanced. (C) 2014 AIP Publishing LLC.

DOI： 10.1063/1.4881676

Language：English   Publishing type：Research paper (scientific journal)  

We have prepared 2 &#37; Al-doped ZnO (AZO) thin films on SrTiO3 substrates by a pulsed laser deposition technique at various deposition temperatures (T (dep) = 300-600 A degrees C). The thermoelectric properties of AZO thin films were studied in a low temperature range (300-600 K). Thin film deposited at 300 A degrees C is fully c-axis-oriented and presents electrical conductivity 310 S/cm with Seebeck coefficient -65 mu V/K and power factor 0.13 x 10(-3) Wm(-1) K-2 at 300 K. The performance of thin films increases with temperature. For instance, the power factor is enhanced up to 0.55 x 10(-3) Wm(-1) K-2 at 600 K, surpassing the best AZO film previously reported in the literature.

DOI： 10.1007/s11664-014-2992-x

Language：English   Publishing type：Research paper (other academic)  

Spectral Absorptance Enhancement of a Gold Coated Micro-particle Array

Language：English   Publishing type：Research paper (scientific journal)  

In this study, we investigated the effect of the structure of microporous p-type (Bi0.4Te3Sb1.6) and n-type (Bi2.0Te2.7Se0.3) BiTe-based thin films on their thermoelectric performance. High-aspect-ratio porous thin films with pore depth greater than 1 mu m and pore diameter ranging from 300 nm to 500 nm were prepared by oxygen plasma etching of polyimide (PI) layers capped with a heat-resistant block copolymer, which acted as the template. The cross-plane thermal conductivities of the porous p- and n-type thin films were 0.4 W m(-1) K-1 and 0.42 W m(-1) K-1, respectively, and the dimensionless figures of merit, ZT, of the p- and n-type BiTe films were estimated as 1.0 and 1.0, respectively, at room temperature. A prototype thermoelectric module consisting of 20 pairs of p- and n-type strips over an area of 3 cm x 5 cm was fabricated on the porous PI substrate. This module produced an output power of 0.1 mW and an output voltage of 0.6 V for a temperature difference of 130A degrees C. The output power of the submicrostructured module was 1.5 times greater than that of a module based on smooth BiTe-based thin films. Thus, the thermoelectric performance of the thin films was improved owing to their submicroscale structure.

DOI： 10.1007/s11664-013-2852-0

Language：English   Publishing type：Research paper (scientific journal)  

2&#37; Al-doped ZnO (AZO) thin films fabricated at 300 C by pulsed laser deposition (PLD) on amorphous fused silica demonstrated the high quality crystallinity and grain connection, which correlates to the high thermoelectric performance: electrical conductivity sigma = 923S/cm and Seebeck coefficient S = -111 mu V/K at 600 K. Its power factor (S-2 center dot sigma) is 1.2 x 10(-3)Wm(-1)K(-2), twofold better than films deposited on crystalline SrTiO3 under the same experimental conditions. Using our measured thermal conductivity (kappa) at 300K (4.89Wm(-1)K(-1)), the figure of merit, ZT = (S-2 center dot sigma center dot T/kappa), is calculated as 0.045 at 600 K, 5 times larger than ZT of our previously reported bulk ZnO. (C) 2014 The Japan Society of Applied Physics

DOI： 10.7567/JJAP.53.060306

Language：English   Publishing type：Research paper (scientific journal)  

We have investigated the origin of crystal orientation for nanocrystalline bismuth telluride-based thin films. Thin films of p-type bismuth telluride antimony (Bi-Te-Sb) and n-type bismuth telluride selenide (Bi-Te-Se) were fabricated by a flash evaporation method, with exactly the same deposition conditions except for the elemental composition of the starting powders. For p-type Bi-Te-Sb thin films the main x-ray diffraction (XRD) peaks were from the c-axis (I {00l} pound/I {hkl} pound = 0.88) whereas n-type Bi-Te-Se thin films were randomly oriented (I {00l} pound/I {hkl} pound = 0.40). Crystal orientation, crystallinity, and crystallite size were improved for both types of thin film by sintering. For p-type Bi-Te-Sb thin films, especially, high-quality structures were obtained compared with those of n-type Bi-Te-Se thin films. We also estimated the thermoelectric properties of the as-grown and sintered thin films. The power factor was enhanced by sintering; maximum values were 34.9 mu W/cm K-2 for p-type Bi-Te-Sb thin films at a sintering temperature of 300A degrees C and 23.9 mu W/cm K-2 for n-type Bi-Te-Se thin films at a sintering temperature of 350A degrees C. The exact mechanisms of film growth are not yet clear but we deduce the crystal orientation originates from the size of nano-clusters generated on the tungsten boat during flash evaporation.

DOI： 10.1007/s11664-013-2896-1

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/admi.201300015

Language：English   Publishing type：Research paper (scientific journal)  

Ca3Co4O9 (p-type) and Zn0.98Al0.02O (n-type) pellets were prepared by conventional sintering (CS) and Spark Plasma sintering (SPS) starting from the oxides. The best p-type sample was SPS Ca3Co4O9 obtained from pre-sintered pellets, with electrical conductivity sigma = 144 S/cm and Seebeck coefficient S = 172 mu V/K at 800 A degrees C, while thermal conductivity kappa = 2.00 W/mxK and figure of merit ZT = 0.23. The best n-type sample was CS Zn0.98Al0.02O showing sigma = 83 S/cm and S = -268 mu V/K at 800 A degrees C, while = 5.03 W/mxK and ZT = 0.127. The output power of a module based on SPS Ca3Co4O9 and CS Zn0.98Al0.02O legs was 2.26 mW (with T = 500 A degrees C, Delta T = 248 A degrees C).

DOI： 10.1007/s12540-014-2024-7

Language：English   Publishing type：Research paper (scientific journal)  

In-plane thermal conductivity of PEDOT-PSS thin films

Language：English  

Thermoelectric Properties of Printed Bismuth Telluride Films

Language：English   Publishing type：Research paper (other academic)  

High Performance Printable Thermoelectric Compound Using Heat Resistant Resin and Conductive Additive

Language：English   Publishing type：Research paper (scientific journal)  

Nano-porous thermoelectric thin films

Language：English  

Thermal and Electrical Conductivities of Porous Si Thin Films

Language：English   Publishing type：Research paper (scientific journal)  

We prepared both n- and p-type bismuth telluride thin films by using a coaxial-type vacuum arc evaporation method. The atomic compositions of the as-grown thin films and several annealed thin films were comparable to that of bulk bismuth telluride. Their thermoelectric properties were measured and found to be comparable to those of bulk materials. The Seebeck coefficient and electrical conductivity of the as-grown thin films were improved by the annealing process. The measured figures of merit (ZT) of the films were 0.86 for the n-type and 0.41 for the p-type at 300 K for annealing temperatures of 573 K and 523 K, respectively.

DOI： 10.1007/s11664-012-2438-2

Language：English   Publishing type：Research paper (scientific journal)  

We prepared a mixture of thermoelectric bismuth telluride particles, a conductive polymer [poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)], poly(acrylic acid) (PAA) and several organic additives to fabricate thermoelectric films using printing or coating techniques. In the mixture, the organic components (PEDOT:PSS, PAA and an additive) act as a binder to connect bismuth telluride particles mechanically and electrically. Among the organic additives used, glycerol significantly enhanced the electrical conductivity and bismuth telluride particle dispersibility in the mixture. Bi0.4Te3.0Sb1.6 films fabricated by spin-coating the mixture showed a thermoelectric figure of merit (ZT) of 0.2 at 300 K when the Bi0.4Te3Sb1.6 particle diameter was 2.8 μm and its concentration in the elastic films was 95 wt.&#37;. © 2013 TMS.

DOI： 10.1007/s11664-012-2420-z

Language：English   Publishing type：Research paper (scientific journal)  

We have prepared 2&#37; Al doped ZnO (AZO) thin films on SrTiO3 (STO) and Al2O3 substrates by Pulsed Laser Deposition technique at various deposition temperatures (Tdep = 300°C-600°C). Transport and thermoelectric properties of AZO thin films were studied in low temperature range (300 K-600 K). AZO/STO films present superior performance respect to AZO/Al2O3 films deposited at the same temperature, except for films deposited at 400°C. Best film is the fully c-axis oriented AZO/STO deposited at 300°C, which epitaxial strain and dislocation density are the lowest: electrical conductivity 310 S/cm, Seebeck coefficient -65 μV/K, and power factor 0.13 × 10-3 W m-1 K-2 at 300 K. Its performance increases with temperature. For instance, power factor is enhanced up to 0.55 × 10 -3 W m-1 K-2 at 600 K, surpassing the best AZO film previously reported in literature. © 2013 AIP Publishing LLC.

DOI： 10.1063/1.4812401

Language：English   Publishing type：Research paper (scientific journal)  

We have reported the growth of single-crystalline bismuth antimony telluride nanoplates on the surface of nanoparticle thin films using a simple sintering process. We prepared two types of bismuth antimony telluride thin films, one comprising nanoparticles and the other submicron particles. The nanoplates were found to grow only on thin films comprising nanoparticles. The structure, composition, and morphology of nanoplates were investigated by using X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray analysis. The obtained nanoplates were of length 0.5-1 mu m and thickness less than 100 nm. The atomic composition of the nanoplates was almost the same as that of the nanoparticles in the thin films. The nanoplates were found to be single crystalline, while the nanoparticles in the thin films were polycrystalline in nature. The growth of nanoplates on the surface of the thin films was due to the partial melting and evaporation of nanoparticles during the sintering process. As a result, the evaporated materials formed nuclei on the surface of the films, which then crystallized to form nanoplates. (C) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jcrysgro.2013.03.028

Language：English   Publishing type：Research paper (scientific journal)  

Bismuth-telluride thermoelectric thin films prepared by coaxial type vacuum arc evaporation method

Language：English   Publishing type：Research paper (scientific journal)  

In-plane Thermal and Electrical Conductivity of Si Thin Film with Periodic Microporous

Language：English   Publishing type：Research paper (scientific journal)  

Fabrication of porous bismuth telluride thin films using micro-phase separation of block copolymer

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Here, we investigate the combined effect of the nanoscale crystal grains and porosity on the lattice thermal conductivity of bismuth-telluride-based bulk alloys using both experimental studies and modeling. The fabricated bulk alloys exhibit average grain sizes of 30 < d < 60nm and porosities of 12&#37; < Phi < 18&#37;. The total thermal conductivities were measured using a laser flash method at room temperature, and they were in the range 0.24 to 0.74W/m/K. To gain insight into the phonon transport in the nanocrystalline and nanoporous bulk alloys, we estimate the lattice thermal conductivities and compare them with those obtained from a simplified phonon transport model that accounts for the grain size effect in combination with the Maxwell-Garnett model for the porosity effect. The results of this combined model are consistent with the experimental results, and it shows that the grain size effect in the nanoscale regime accounts for a significant portion of the reduction in lattice thermal conductivity. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4759326]

DOI： 10.1063/1.4759326

Language：English   Publishing type：Research paper (scientific journal)  

Effects of Micro-Structures on In-plane Thermal Conductivity and Electrical Conductivity of Silicon Thin Film

Language：English   Publishing type：Research paper (scientific journal)  

We fabricated in-plane thermoelectric modules (4 mm x 4 mm) on a 4-m-thick substrate using a vacuum deposition process through a shadow mask. In this study, a thermoelectric - pair was established using multilayered films of and thermoelectric thin films and an insulator film with a hole at the center. The output power was 58 nW at 443 K using the multilayered microgenerator. We discuss the effects of device thickness on the efficiency of the microgenerator to increase the output electric power. We evaluated the output power of the in-plane thermoelectric generator with a substrate using a one-dimensional heat conduction model, and it was found to depend on the thickness of the thermoelectric film. If the thermoelectric film is very thin, the power factor is more important than the nondimensional figure of merit, . Metal thin films with high power factor are more efficient than semiconductors with low power factors even though their thermal conductivities are high. When the thermoelectric thin film is thick, should be higher for larger output power of the device.

DOI： 10.1007/s11664-012-2067-9

Language：English   Publishing type：Research paper (scientific journal)  

In this study, we introduce our numerical and experimental works for the thermal conductivity reduction by using a porous material. Recently thermal conductivity reduction has been one of the key technologies to enhance the figure of merit (ZT) of a thermoelectric material. We carry out numerical calculations of heat conduction in porous materials, such as phonon Boltzmann transport (BTE) and molecular dynamics (MD) simulations, in order to investigate the mechanism of the thermal conductivity reduction of a porous material. In the BTE, we applied the periodic boundary conditions with constant heat flux to calculate the effective thermal conductivity of porous materials.In the MD simulation, we calculated the phonon properties of Si by using the Stillinger-Weber potential at constant temperature with periodic boundary conditions in the x, y, and z directions. Phonon dispersion curves of single crystal of Si calculated from MD results by time-space 2D FFT are agreed well with reference data. Moreover, the effects of nanoporous structures on both the phonon group velocity and the phonon density of states (DOS) are discussed. At last, we made a porous p-type Bi2Te3 by nanoparticles prepared by a beads milling method. The thermal conductivity is one-fifth of that of a bulk material as well as keeping the same Seebeck coefficient as the bulk value. However, electrical conductivity was much reduced, and the ZT was only 0.048. [DOI: 10.1115/1.4005709]

DOI： 10.1115/1.4005709

Language：English   Publishing type：Research paper (other academic)  

Spectral Absorptance of Micro-structures of Self-assembled Silica Particles

Language：English   Publishing type：Research paper (other academic)  

Reflectance of Photonic Crystals of Self-assembled Silica Particles

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In-Plane Thermal Conductivity and Electrical Conductivity Measurements of Silicon Thin Film

Language：English   Publishing type：Research paper (other academic)  

Thermal Conductivity of Bismuth Antimony Telluride Thin Films formed on Porous Films Prepared from Block Copolymer

Language：English   Publishing type：Research paper (scientific journal)  

Effects of Micro-Structures on Thermal Conductivity and Electrical Conductivity

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Thermoelectric properties of n-type C-60 thin films and their application in organic thermovoltaic devices
The high performance of n-type organic thin-film thermoelectric elements utilizing a bilayer structure composed of C-60 and Cs2CO3 was demonstrated. By employing an underlying layer, the electrical conductivity and the power factor of the n-type thermoelectric elements were significantly improved, and a maximum power factor of 20.5 mu W m(-1) K-2 at room temperature was demonstrated. In addition, an organic p-n prototype thermovoltaic device was demonstrated. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3631633]

DOI： 10.1063/1.3631633

Language：English  

Enhanced Figure of Merit of a Porous Thin Film of Bismuth Antimony Telluride

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Enhanced figure of merit of a porous thin film of bismuth antimony telluride
A porous thin film of Bi(0.4)Te(3)Sb(1.6) with an enhanced figure of merit of 1.8 at room temperature was fabricated by flash evaporation on an alumina substrate containing hexagonally arranged nanopores with an average diameter of 20 nm, separated by an average distance of 50 nm. The thermal conductivity was significantly reduced compared with standard Bi(0.4)Te(3)Sb(1.6) films to 0.25 W/(m.K) with no major decrease in either the electrical conductivity (398 S/cm) or the Seebeck coefficient (198 mu V/K). The reduction in thermal conductivity was rationalized using a model for the full distribution of the phonon mean free path in the film. (c) 2011 American Institute of Physics. [doi:10.1063/1.3543852]

DOI： 10.1063/1.3543852

Language：English   Publishing type：Research paper (scientific journal)  

Process optimization of preparing honeycomb-patterned polystyrene films by breath figure method
Honeycomb-patterned polystyrene film is prepared by breath figure method. Pore size with a few hundred nano-meter to several micro-meter diameters is generated by controlling various parameters, such as the polymer concentration, humidity, casting area and solvent. The pore size becomes larger with increasing humidity and temperature difference between air and substrate. Porous film can be formed by drying under high humidity. The density of solvents affect the pore shape and pore depth. Video observation indicates that in the formation process of the porous pattern water droplet condenses gradually on the surface, along with the migration of the droplet formation boundary line from the edge to the center, when the boundary line reaches the center, hexagonally packed porous template is completed.

DOI： 10.1007/s12206-010-1010-3

Language：English   Publishing type：Research paper (scientific journal)  

Improved thermoelectric performance of highly-oriented nanocrystalline bismuth antimony telluride thin films
Improved thermoelectric performance of highly-oriented nanocrystalline bismuth antimony telluride thin films is described The thin films are deposited by a flash evaporation method followed by annealing in hydrogen By optimizing the annealing conditions the resulting thin films exhibit almost perfect orientation with the c-axis normal to the substrate and are composed of nano-sized grains with an average grain size of 150 nm The in-plane electrical conductivity and Seebeck coefficient were measured at room temperature The cross-plane thermal conductivity of the thin films was measured by a 3 omega method and the in-plane thermal conductivity was evaluated by using an anisotropic factor of thermal conductivity based on a single crystal bulk alloy with almost the same composition and carrier concentration The measured cross-plane thermal conductivity is 0 56 W/(m K) and the in-plane thermal conductivity is evaluated to be 1 05 W/(m K) Finally the In-plane power factor and figure-of-merit ZT of the thin films are 35 6 mu W/(cm K(2)) and 1 0 at 300 K respectively (C) 2010 Elsevier B V All rights reserved

DOI： 10.1016/j.tsf.2010.08.013

Language：English   Publishing type：Research paper (scientific journal)  

Improved thermoelectric performance of organic thin-film elements utilizing a bilayer structure of pentacene and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F-4-TCNQ)
We demonstrate an improved thermoelectric performance of small molecular thin films fabricated by thermal deposition of pentacene as a p-type conduction layer. To enhance the performance, a bilayer structure composed of an intrinsic pentacene layer and an acceptor 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane layer is utilized as the prototype thermoelectric element. With the bilayer structure, the electrical conductivity reaches 0.43 S/cm, exhibiting a positive Seebeck coefficient of about 200 mu V/K. We thus obtain a high power factor of 2.0 mu W/mK(2) with an optimized layer thickness. (C) 2010 American Institute of Physics. [doi:10.1063/1.3456394]

DOI： 10.1063/1.3456394

Language：English   Publishing type：Research paper (scientific journal)  

The cross-plane thermal conductivity of highly oriented nanocrystalline bismuth antimony telluride thin films is investigated. The thin film was deposited by a flash evaporation method. The resulting film was oriented with the c-axis to the substrate, and was composed of fine grains with an average grain size of 150 nm. The cross-plane thermal conductivity of the film was measured by a 3 omega method at room temperature, and was determined to be 0.6 W m(-1) K(-1). Compared to the single crystal bulk alloy of nearly the same composition and carrier concentration, the thin film exhibited a 20&#37; reduction in the thermal conductivity. (c) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2009.10.117

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Preparation of Nano-Porous Polymer Films having the Smallest Size of 80nm under High Humidity Conditions

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Numerical Calculation of A Nano-Porous Polymer Film Processing

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Numerical Calculation for Fabrication of a Nano-Porous Polymer Film

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Evaluation of Thermal Conductivity in BiTe Thin Film

Language：English   Publishing type：Research paper (scientific journal)  

Using shadow masks prepared by standard microfabrication processes, we fabricated in-plane thermoelectric microdevices (4 mm x 4 mm) made of bismuth telluride thin films, and evaluated their performance. We used Bi0.4Te3.0Sb1.6 as the p-type semiconductor and Bi2.0Te2.7Se0.3 as the n-type semiconductor. We deposited p- and n-type thermoelectric thin films on a free-standing thin film of Si3N4 (4 mm x 4 mm x 4 mu m) on a Si wafer, and measured the output voltages of the microdevices while heating at the bottom of the Si substrate. The maximum output voltage of the thermoelectric device was 48 mV at 373 K.

DOI： 10.1007/s11664-009-0819-y

Language：English  

Thermal Conductivity of Nano-porous Bismuth Telluride Thin Films

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Thermal conductivity of vertically-aligned single-walled carbon nanotube film measured by 3 omega method

Language：English   Publishing type：Research paper (scientific journal)  

The spectral reflectance of microperiodic structures of silica microspheres was investigated. The electromagnetic dispersion relation in a close-packed structure of silica spheres is computed. The three-dimensional close-packed structures, self-assembled with silica microspheres (2 mu m and 3 mu m), were rapidly fabricated over a large area. Specular reflectance was measured by using Fourier transform-infrared spectroscopy (FT-IR). The experimental results were evaluated by a modification of Bragg's law, taking into account Snell's law of refraction, and calculations of multiple reflections and the scalar wave approximation method. In addition, to expand the reflection wavelength range, a double-layered sample was fabricated, and its spectral reflectance was determined.

DOI： 10.1007/s10765-008-0483-0

Language：Japanese  

Visualization and Numerical Analysis of Unsteady Flow in Pump Sump
Numerical and experimental studies were done on unsteady flow in a pump sump to study the generation of air core vortex and submerged vortex, which cause vibration and acoustic noise. The geometry of the free surface in the test pump sump was visualized by Moire method, and velocities near pump suction were measured by PIV. Unsteady flow in the pump sump was calculated using VOF method in a commercial CFD software, and calculated velocities as well as free surface geometry were compared with measured ones. The present study showed that CFD can capture unsteady flow in a pump sump with a reasonable accuracy, and that the air core vortex as well as submerged vortex can be predicted by CFD.

DOI： 10.11458/tsj.36.746

Language：English  

Zone folding effects of heat conduction in nano-porous silicon

Language：English  

Thermal Conductivity of Nano-Structured Bismuth Telluride Thin Films

Language：English   Publishing type：Research paper (scientific journal)  

An inverse transient method with genetic algorithm (GA) was applied to leak detection in pipeline. Transient flow caused by valve operation was calculated using the characteristics method. The location and discharge of leak were determined so that the difference of the calculated pressure may be minimized from the reference pressure calculated under a given leak condition. Calculations were done for the leak at one and two locations in pipeline. Furthermore, the effect of noise in pressure data was discussed, and the leak locations and leak discharges can he predicted precisely even in the case of noisy data.

DOI： 10.1007/s12206-008-0735-8

Language：English  

Effects of Channel Geometry for a Diffuser/Nozzle Valveless Micropump

Language：English   Publishing type：Research paper (scientific journal)  

The effect of grain size on the thermoelectric properties of n-type nanocrystalline bismuth-telluride based thin films is investigated. We prepare the nanocrystalline thin films with average grain sizes of 10, 27, and 60 nm by a flash-evaporation method followed by a hydrogen annealing process. The thermoelectric properties, in terms of the thermal conductivity by a differential 3 omega method, the electrical conductivity, and the Seebeck coefficient are measured at room temperature and used to evaluate the figure of merit. The minimum thermal conductivity is 0.61 W m(-1) K(-1) at the average grain size of 10 nm. We also estimate the lattice thermal conductivity of the nanocrystalline thin films and compare it with a simplified theory of phonon scattering on grain boundaries. For nanosized grains, the lattice thermal conductivity of nanocrystalline thin films decreases rapidly for smaller grains, corresponding to the theoretical calculation. The figure of merit is also decreased as the grain size decreases, which is attributed to the increased number of defects at the grain boundaries. (C) 2008 American Institute of Physics. [DOI: 10.1063/1.2990774]

DOI： 10.1063/1.2990774

Language：English  

In-Plane Termoelectric Micro-Generator on a Free StandingG Si_3N_4 Thin Film

Language：English  

Thermoelectric Properties of Nano-Structured Bismuth TellurideThin Films

Language：English   Publishing type：Research paper (other academic)  

Thermal conductivity characterization of vertically-aligned single-walled carbon nanotube films

Language：English  

Thermal Conduction of Si Nano-porous Structure

Language：English  

Scale effect for diffuser/nozzle valveless micropump

Language：English   Publishing type：Research paper (scientific journal)  

In this article, we perform a preliminary study to assemble micro-size thermoelectric devices with low-cost fabrication by a preparation of nanoparticles and their thin films. Bi0.4TC3.0Sb1.6 nanoparticles with an average size of approximately 50nm are fabricated by a beads-milling method. The nanoparticle solution is prepared by mixing with toluene and a surfactant, and thin films with 1 mu m thick are deposited on Al2O3 substrates by a printing method. The thin films are sintered at temperatures ranging from 300 to 500 degrees C for 60 min in hydrogen ambient. We investigate the thin film structures and the thermoelectric properties at room temperature. As the sintering temperature increases, hexagonal-shaped crystals are grown on the film surface while the atomic composition is almost constant throughout all the sintering temperatures. The XRD patterns indicate that all the nanoparticle thin films are found to mostly exhibit the same XRD intensities and have multiple peaks correspond to each other. The in-plane electrical conductivity of the thin films increases but. the Seebeck coefficient decreases as the sintering temperature increases. As a result, the best performance of the thermoelectric power factor of 1.3 mu W/(cm K-2) is achieved at a sintering temperature of 350 degrees C. (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2007.08.054

Language：English   Publishing type：Research paper (other academic)  

The fabrication and evaluation of the thermoelectric micro-generator on a free-standing substrate
主要論文集（会議）

Language：English   Publishing type：Research paper (scientific journal)  

Structural and thermoelectric properties of p-type fine-grained Bi(0.4)Te(3.0)Sb(1.6) thin films are investigated. The films are deposited by a flash evaporation method and exhibit a preferred orientation in the c-axis direction. By optimizing deposition conditions, we achieve thin films with clean surfaces. Then in order to enhance the crystallinity with preferred orientation, as well as the thermoelectric properties of the thin films, they are annealed in hydrogen ambient at atmospheric pressure and at temperatures ranging from 200 to 350 'C. The cross-section microstructure and crystallinity of the thin films are investigated by scanning electron microscopy and X-ray diffraction, respectively. The electrical conductivity, Seebeck coefficient, and thermoelectric power factor are measured at room temperature. We confirm that the grain growth and the crystallization along the c-axis are enhanced as the annealing temperature increases. The highest performance of p-type Bi(0.4)Te(3.0)Sb(1.6) thin films observed in this study have an annealing temperature of 300 degrees C, resulting in a thennoelectric power factor of 34.9 mu W cm(-1) K(-2) at the average grain size of 88 nm. We consider that the synthesis conditions reduce the number of potential scattering sites at grain boundaries and defects, thus improving the thermoelectric power factor. (c) 2007 Elsevier B.V All rights reserved.

DOI： 10.1016/j.tsf.2007.12.130

Language：Japanese  

Leak Detection in Pipe Using Genetic Algorithm and Inverse Transient Method : (2nd Report, Leaks at Two Points)
Leak detection for leaks at two points was done using the inverse transient method and genetic algorithm. The locations and discharges of each leak were selected as GA parameters for leaks at two points in pipeline. The steady pressures and leak discharges at all nodes were calculated using Newton iteration method. Calculations under assumption of two leaks points were done for not only leaks at two points but also leak at one point in pipeline. Furthermore, the effect of noise in pressure data was discussed, and the leak locations and leak discharges can be predicted precisely even in the ...

DOI： 10.11458/tsj.36.359

Language：English   Publishing type：Research paper (other academic)  

Thermal conductivity of vertically-aligned single-walled carbon nanotube film measured by 3omega method

Language：Japanese  

非対称流路を利用したバルブレスマイクロポンプ

Language：Japanese  

Leak Detection in Pipe Using Genetic Algorithm and Inverse Transient Method

DOI： 10.11458/tsj.36.173

Language：English   Publishing type：Research paper (other academic)  

Fabrication of Nanoparitcle P-type Bismuth Telluride Thin Films and Their Thermoelectric Properties

Language：English   Publishing type：Research paper (other academic)  

Directional Spectral Emittance of Close-packed Silica Micro-Spheres

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Phonon Transport Simulation for Nano/Microscale Heat Conduction

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Numerical Analysis of Heat Conduction in Nanostructured Silicon

Language：English   Publishing type：Research paper (scientific journal)  

Bi0.4Te3.0Sb1.6 thin films on glass substrates are fabricated by a flash evaporation method. In order to enhance the transport properties of the thin films, annealing in argon ambient at atmospheric pressure is carried out for 1 h in the temperature range from 200 to 400 degrees C. The structure of the thin films, in terms of homogeneous composition and crystallinity, is investigated by energy dispersive X-ray spectroscopy and X-ray diffraction, respectively. The microstructure of the thin films is examined using scanning electron microscopy. We confirm that as-deposited Bi0.4Te3.0Sb1.6 thin films have a mostly homogeneous structure except for a few extra stuck particles. At higher annealing temperatures, the crystallinity of the thin films is improved and the size of crystal grains increases to the same size as the film thickness. However, excessive high annealing temperatures cause porous thin films due to the evaporation of tellurium. The transport properties of the thin films, in terms of the electrical resistivity, the Seebeck coefficient and the thermoelectric power factor are determined at room temperature. By optimizing the annealing conditions, it is possible to obtain a high-performance thin film with a thermoelectric power factor of 12.2 mu W cm(-1) K-2. We consider that the performance of the thin films is enhanced for optimized annealing because of reductions in the importance of grain boundary scattering. (C) 2006 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jallcom.2006.09.136

Language：English   Publishing type：Research paper (scientific journal)  

Bismuth-telluride-based alloy thin film thermoelectric generators are fabricated by a flash evaporation method. We prepare Bi0.4Te3.0Sb1.6 (P-type) and Bi2.0Te2.7Se0.3 (n-type) powders for the fabrication of the flash evaporated thin films. The overall size of the thin film thermoelectric generators, which consist of seven pairs of legs connected by aluminum electrodes, is 20 mm by 15 mm. Each leg is 15 turn long, 1 turn wide and 1 mu m thick. We measure the output voltage and estimate the maximum output power near room temperature as a function of the temperature difference between hot and cold junctions of the thin film thermoelectric generators. In order to improve the performance of the generators, a hydrogen annealing process is carried out at several temperatures from 25 degrees C to 250 degrees C. The highest output voltage of 83.3 mV and estimated Output power of 0.21 mu W are obtained from a hydrogen annealing temperature of T-a = 250 degrees C and a temperature difference of Delta T = 30 K. The hydrogen annealing temperature of T-a = 250 degrees C also results in the best electrical performance for both p-type thin film (Seebeck coefficient= 254.4 mu V/K, resistivity = 4.1 m Omega cm, power factor = 15.9 mu W/cm K-2) and n-type thin film (- 179.3 mu V/K, 1.5 m Omega cm, 21.5 mu W/cm K-2). (C) 2007 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.sna.2007.05.030

Language：English   Publishing type：Research paper (scientific journal)  

The thermal conductivity of n-type nanocrystalline bismuth-telluride-based thin films (Bi2.0Te2.7Se0.3) is investigated by a differential 3 omega method at room temperature. The nanocrystalline thin films are grown on a glass substrate by a flash evaporation method, followed by hydrogen annealing at 250 degrees C. The structure of the thin films is studied by means of atomic force microscopy, x-ray diffraction, and energy-dispersive x-ray spectroscopy. The thin films exhibit an average grain size of 60 nm and a cross-plane thermal conductivity of 0.8 W/m K. The in-plane electrical conductivity and in-plane Seebeck coefficient are also investigated. Assuming that the in-plane thermal conductivity of the thin films is identical to that of the cross-plane direction, the in-plane figure of merit of the thin films is estimated to be ZT=0.7. As compared with a sintered bulk sample with average grain size of 30 mu m and nearly the same composition as the thin films, the nanocrystalline thin films show approximately a 50&#37; reduction in the thermal conductivity, but the electrical conductivity also falls 40&#37;. The reduced thermal and electrical conductivities are attributed to increased carrier trapping and scattering in the nanocrystalline film. (c) 2007 American Institute of Physics.

DOI： 10.1063/1.2717867

Language：English   Publishing type：Research paper (other academic)  

Micro-Scale Heat Transport Modeling Using Equation of Phonon Radiative Transfer

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Reflectivity of Micro Periodic Structure with Silica Spheres

Language：English   Publishing type：Research paper (scientific journal)  

The structure and thermoelectric properties of boron doped nanocrystalline Si0.8Ge0.2 thin films are investigated for potential application in microthermoelectric devices. Nanocrystalline Si0.8Ge0.2 thin films are grown by low-pressure chemical vapor deposition on a sandwich of Si3N4/SiO2/Si3N4 films deposited on a Si (100) substrate. The Si0.8Ge0.2 film is doped with boron by ion implantation. The structure of the thin film is studied by means of atomic force microscopy, x-ray diffraction, and transmission electron microscopy. It is found that the film has column-shaped crystal grains similar to 100 nm in diameter oriented along the thickness of the film. The electrical conductivity and Seebeck coefficient are measured in the temperature range between 80-300 and 130-300 K, respectively. The thermal conductivity is measured at room temperature by a 3 omega method. As compared with bulk silicon-germanium and microcrystalline film alloys of nearly the same Si/Ge ratio and doping concentrations, the Si0.8Ge0.2 nanocrystalline film exhibits a twofold reduction in the thermal conductivitity, an enhancement in the Seebeck coefficient, and a reduction in the electrical conductivity. Enhanced heat carrier scattering due to the nanocrystalline structure of the films and a combined effect of boron segregation and carrier trapping at grain boundaries are believed to be responsible for the measured reductions in the thermal and electrical conductivities, respectively. (c) 2006 American Institute of Physics.

DOI： 10.1063/1.2337392

Language：English   Publishing type：Research paper (other academic)  

Reflectivity of Micro Periodic Structure Generated with Silica Microspheres

Language：English   Publishing type：Research paper (scientific journal)  

The phonon Boltzmann equation is solved numerically in order to study the phonon thermal conductivity of micro/nanostructured thin films with open holes in a host material. We focused on the size effect of embedded pores and film thickness on the decrease in thermal conductivity of the film. Simulations have revealed that the temperature profiles in the micro/nanostructured materials are very different from those in their bulk counterparts, due to the ballistic nature of the microscale phonon transport. These simulations clearly demonstrate that the conventional Fourier beat conduction equation cannot be applied to study heat conduction in solids at microscale. The effective thermal conductivity of thin films with micro/nanoholes is calculated from the applied temperature difference and the heat flux. In the present paper, the effective thermal conductivity is shown as a function of the size of the micro/nanoholes and the film thickness. For example, when the size of the hole becomes. approximately 1/20th the phonon mean free path in a film, the thickness is 1/10th the mean free path of phonons and the effective thermal conductivity decreases to as low as 6&#37; of the bulk value. The distribution of holes also affects the reduction in the effective thermal conductivity. Thin films embedded with staggered-hole arrays have slightly lower effective thermal conductivities than films with aligned-hole arrays. The cross-sectional area in the thermal transport direction is a significant parameter with respect to the reduction of thermal conductivity. The results of the present study may prove useful in the development of artificial micro/nanostructured materials, including thermoelectrics and low-k dielectrics.

DOI： 10.1109/TCAPT.2006.875905

Language：English  

Reflectivity of Silica Micro Periodic Structures

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n-type Bi2Te3 Thin Film Fabrication by Using a Flash Vapor Deposition Method

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Thermal conductivity of a nano-structured material

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Development of an active controlled airfoil preventing flow separation

Language：English   Publishing type：Research paper (other academic)  

Thermal Radiative Properties of Photonic Cryatals

Language：English   Publishing type：Research paper (other academic)  

Measurement of the spectral directional reflectivity of silica photonic crystals

Language：English   Publishing type：Research paper (other academic)  

Measurement of the spectral directional reflectivity of silica photonic crystals

Language：English   Publishing type：Research paper (other academic)  

Numerical study on Y-shaped Valve-less Micro-pump

Language：English   Publishing type：Research paper (other academic)  

Numerical simulations of Heat transfer in Nanoscopic area

Language：Japanese  

Language：English   Publishing type：Research paper (other academic)  

Thermal conductivities of nano-structured materials

Language：English   Publishing type：Research paper (other academic)  

Study on Diffuser Pump Instability at Off-Desing Conditions

Language：English   Publishing type：Research paper (scientific journal)  

Numerical Simulations of Boltzmann Equations for Heat transfer at Microscopic Area

Language：English   Publishing type：Research paper (other academic)  

Fabrication of Photonic Crystals for the Control of the Radiative Properties

Language：English   Publishing type：Research paper (other academic)  

Numerical Simulation of Centrifugal Blood Pumps for the Improvement of Antithrombogenecity

Language：English   Publishing type：Research paper (other academic)  

Radiative Properties of Bio-mimetic Photonic Crystals

Language：English   Publishing type：Research paper (other academic)  

Molecular dynamics simulations on the thermal conductivity of Si-Ge superlattices
We conducted molecular dynamics (MD) simulations on heat transfer in Si-Ge superlattices to investigate the effects of nano-structures on thermal conductivities. Both the perpendicular thermal conductivity to the interfaces (cross-plane) and the parallel one to the interfaces (in-plane) were calculated. The layered system had a lower conductivity than the uniform system. When the number of layers was increased while keeping the total sample thickness constant, the cross-plane thermal conductivity decreased. We calculated the kinetic energy profile to investigate the mechanism of this decrease. The motions of atoms at the boundaries between Si and Ge were suppressed, and it became thermal resistance.

Language：English   Publishing type：Research paper (other academic)  

Temperature measurements with micro-TFTCs
We fabricate metal thin film thermocouples (TFTCs). Au-Pt, Cu-Ni, and W-Ni are deposited on a glass plate using standard thin film processes. The dimension of thermocouple junction is 30μm×300μm. The thermoelectric powers of TFTCs are different from those of bulk because diffusion of electrons is restricted by the very thin film. However TFTCs are still useful for temperature measurements because the thermoelectric voltage is proportional to measured temperature at thermocouple junction. The response time of Au-Pt TFTCs is about 30ns when the surface of the glass is heated by a YAG pulsed laser. The result compares favorably with measurements by a thermoreflectance method. We also describe W-Ni nano-TFTCs with micro-heater fabricated by Focused Ion Beam for the measurement of absolute temperature distribution in 10 micron area. In order to reduce the size of the TFTCs we employ a 3-dimensional structure.

Language：English   Publishing type：Research paper (other academic)  

Development of a Valve-less Micro-pump with an Asymmetric Micro-Channel

Language：English   Publishing type：Research paper (other academic)  

Experimental study on unstable characteristics of mixed-flow pump at low flow-rates
Static and dynamic characteristics of a mixed flow pump were measured at low flow rate, where the steady characteristic curves show a positive slope. Unsteady flow was measured at upstream and downstream of impeller, as well as on the casing wall of diffuser passage by using a fast response five-hole pitot tube and semi-conductor type pressure transducers. Dynamic response of the pump to the sinusoidal change in flow rate was measured under constant rotational speed. As a result of the unsteady flow measurements, the positive slope of steady characteristic was found to be caused by the impeller tip separation, inlet backflow, and pre-rotation. Moreover, the dynamic characteristics of the pump were found to become unstable with the increased frequency of flow rate.

DOI： 10.1115/fedsm2003-45103

Language：English   Publishing type：Research paper (other academic)  

Effect of Impeller Tip Leakage Flow on Hydrodynamic Forces

Language：English   Publishing type：Research paper (other academic)  

Experimental Study of Unsteady Phenomena in a Diffuser Pump at Off-design Conditions

Language：English   Publishing type：Research paper (scientific journal)  

Molecular simulations using a genetic algorithm are conducted to investigate stable structures of clusters and deposited atoms on substrates. First, the stable structures of N-atom clusters are calculated. where an icosahedron is found to be the most stable form of a 13-atom cluster. Secondly, stable structures of deposited atoms on a solid surface are investigated. The simulation shows that deposited atoms have either an island or a layer structure, depending on the combination of intermolecular potentials between the deposited and substrate atoms. The present simulation is based on statics, which demands little computing power. (C) 2001 Elsevier Science B.V. All rights reserved.

Language：English   Publishing type：Research paper (other academic)  

Molecular dynamics simulation on the vibration of atoms in Si-Ge superlattices

Language：English   Publishing type：Research paper (other academic)  

Development of a bubble actuated micro pump

Language：English   Publishing type：Research paper (other academic)  

Photonic and Radiative Properties of Bubble Arrays

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (other academic)  

Condensation Dynamic on a solid surface in Thin Film prcessing

Language：English   Publishing type：Research paper (other academic)  

Genetic Algorithm Simulation for Deposited Atoms

Language：English   Publishing type：Research paper (other academic)  

Fundamental study on the Formation of Mctal Clusters

Language：English   Publishing type：Research paper (other academic)  

Nucleation in Thin Film Processing

Responsible for pages：総ページ数：341, 担当ページ数：235-243   Language：Japanese   Book type：Scholarly book

Next Generation Thermoelectric Materials and Modules

Language：Japanese   Book type：Scholarly book

第3章 第2節 エネルギー変換と熱物性・界面物性(pp.88-95) 第7章 第16節 熱電マイクロジェネレーター（pp.387-395）

Language：Japanese  

Language：Japanese  

Language：Japanese  

Language：Japanese  

Language：Japanese  

Nano/Microscale Thermophysical Properties Handbook

Language：Japanese  

第1章 熱電変換材料の技術課題、変換効率・耐久性向上、トラブル対策 第7節 ナノポーラスによる従来の熱電変換材料の効率改善、技術課題とその対応

Language：Japanese  

Energy Harvesting Handbook

Language：Japanese  

Language：Japanese  

2012 Energy Harvesting Technology Outlook

Language：Japanese  

Fundamentals and Applications of Thermoelectrics -Guidepost to Green Society-

Language：Japanese  

Language：Japanese  

Language：Japanese  

Event date： 2025.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：沖縄   Country：Japan  

Event date： 2025.5

Language：English   Presentation type：Oral presentation (general)  

Venue：Okinawa   Country：Japan  

Event date： 2025.3

Language：Japanese   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：小倉   Country：Japan  

Event date： 2025.3

Language：Japanese  

Venue：大分   Country：Japan  

Event date： 2025.3

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Venue：大分   Country：Japan  

Event date： 2025.3

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Event date： 2024.12

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Event date： 2024.11

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Country：Japan  

Event date： 2024.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2024.11

Language：English   Presentation type：Oral presentation (general)  

DOI： 10.1109/ICSJ62869.2024.10804725

Event date： 2024.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Taoyuan   Country：Taiwan, Province of China  

Event date： 2024.10

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Event date： 2024.10

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Venue：新山口   Country：Japan  

Event date： 2024.9

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Event date： 2024.7

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Venue：Sapporo   Country：Japan  

Event date： 2024.7

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Venue：Sapporo   Country：Japan  

Event date： 2024.6 - 2024.7

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Venue：Krakow   Country：Poland  

Event date： 2024.6 - 2024.7

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Venue：Krakow   Country：Poland  

Event date： 2024.6

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Venue：Shanghai   Country：China  

Event date： 2024.6

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Venue：Shanghai   Country：China  

Event date： 2024.6

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Venue：Shanghai   Country：China  

Event date： 2024.6

Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

Venue：生駒   Country：Japan  

Event date： 2024.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神戸   Country：Japan  

Event date： 2024.5

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Venue：神戸   Country：Japan  

Event date： 2024.4

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Venue：Seattle   Country：United States  

Event date： 2024.2

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Venue：Sendai  

Event date： 2023.12

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Venue：Tsukuba   Country：Japan  

Event date： 2023.12

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Venue：Kyoto   Country：Japan  

Event date： 2023.12

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Venue：Honolulu   Country：United States  

Event date： 2023.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：船橋   Country：Japan  

Event date： 2023.10 - 2023.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Birmingham   Country：United Kingdom  

Event date： 2023.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：神戸   Country：Japan  

Event date： 2023.9

Language：Japanese  

Venue：小倉   Country：Japan  

Event date： 2023.9

Language：Japanese  

Venue：小倉   Country：Japan  

Event date： 2023.8 - 2023.9

Language：English   Presentation type：Oral presentation (general)  

Venue：京都大学宇治おうばくプラザ きはだホール   Country：Japan  

Event date： 2023.8

Language：English   Presentation type：Symposium, workshop panel (public)  

Venue：Cape Town   Country：South Africa  

Event date： 2023.8

Language：English   Presentation type：Oral presentation (general)  

Venue：Cape Town   Country：South Africa  

Event date： 2023.8

Language：English   Presentation type：Oral presentation (general)  

Venue：沖縄（ハイブリッド）   Country：Japan  

Event date： 2023.7

Language：English   Presentation type：Oral presentation (general)  

Venue：San diego   Country：United States  

Event date： 2023.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Kyoto   Country：Japan  

Event date： 2023.6

Language：English  

Venue：Singapore   Country：Singapore  

Event date： 2023.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Seatle   Country：United States  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Online   Country：Other  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：徳島   Country：Japan  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.6

Language：Japanese   Presentation type：Symposium, workshop panel (public)  

Venue：徳島   Country：Japan  

Event date： 2023.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡   Country：Japan  

Event date： 2023.5

Language：Japanese  

Venue：福岡   Country：Japan  

Event date： 2023.1

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2022.10

Language：English  

Venue：Kokura   Country：Japan  

Event date： 2022.10

Language：English  

Venue：Kokura   Country：Japan  

Event date： 2022.10

Language：English  

Venue：Kokura   Country：Japan  

Event date： 2022.10

Language：English  

Venue：Kokura   Country：Japan  

Event date： 2022.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2022.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Online   Country：Japan  

Event date： 2022.8

Language：Japanese  

Venue：長岡   Country：Japan  

Event date： 2022.8

Language：Japanese  

Venue：長岡   Country：Japan  

Event date： 2022.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：岐阜   Country：Japan  

Language：English  

Venue：フランス ナンシー   Country：Other  

Thermal Conductivity of Nano-porous Themoelectric Material

Language：Japanese  

Venue：熊本   Country：Other  

Language：Japanese  

Venue：熊本   Country：Other  

Language：Japanese  

Venue：熊本   Country：Other  

Language：Japanese  

Venue：熊本   Country：Other  

Language：Japanese  

Venue：熊本   Country：Other  

Language：Japanese  

Country：Other  

Language：Japanese  

Venue：札幌   Country：Other  

Language：Japanese  

Venue：札幌   Country：Other  

Language：Japanese  

Venue：札幌   Country：Other  

Language：English  

Venue：Shanghai, China   Country：Other  

Development of a Multi-layered In-plane Thermolectric Module（共著）

Language：Japanese  

Venue：東京   Country：Other  

Language：Japanese  

Venue：東京   Country：Other  

Language：Japanese  

Venue：松江   Country：Other  

Language：Japanese  

Venue：徳島   Country：Other  

Language：Japanese  

Venue：霧島   Country：Other  

Language：Japanese  

Venue：徳島   Country：Other  

Language：Japanese  

Venue：長岡   Country：Other  

Language：Japanese  

Venue：長岡   Country：Other  

Language：Japanese  

Venue：松江   Country：Other  

Language：Japanese  

Country：Other  

Language：Japanese  

Venue：北九州   Country：Other  

Language：Japanese  

Venue：福岡   Country：Other  

Language：Japanese  

Venue：大分   Country：Other  

Language：Japanese  

Venue：大分   Country：Other  

Language：Japanese  

Venue：福岡   Country：Other  

Language：Japanese  

Venue：福岡   Country：Other  

Language：English  

Venue：岡山   Country：Other  

薄膜型マイクロジェネレーターの熱設計と性能評価 (共著）

Language：Japanese  

Venue：岡山   Country：Other  

Language：Japanese  

Venue：岡山   Country：Other  

Language：English  

Venue：Traverse City (U.S.A.)   Country：Other  

The effects of thermoelectric film thickness on the performance of in-plane thermoelectric modules (共著）

Language：English  

Venue：Traverse City (U.S.A.)   Country：Other  

Printed thermoelectric thick film for thermoelectric generator (共著）

Language：English  

Venue：Traverse City (U.S.A.)   Country：Other  

Enhanced Figure of Merit of a Nano-porous Thin Film (共著）

Language：Japanese  

Venue：札幌   Country：Other  

Fabrication and thermoelectric characterization of nano-crystal p-type Bi₂Te₃

Language：Japanese  

Venue：北九州   Country：Other  

Language：Japanese  

Venue：東京   Country：Other  

Fabrication of a Multi-layered ln- plane Thermoelectric Module and its Evaluation (jointly worked)

Language：Japanese  

Venue：東京   Country：Other  

Heat Transfer Characterization of Microchannel by Numerical Calculation (jointly worked)

Language：Japanese  

Venue：北九州   Country：Other  

Language：Japanese  

Venue：つくば   Country：Other  

Language：Japanese  

Venue：浜松   Country：Other  

Fabrication of Porous Polymer Thin Film by Self-organization "jointly worked"

Language：Japanese  

Venue：桐生   Country：Other  

Thermal Conductivity of Bi₂Te₃ Thin Film

Language：Japanese  

Venue：横浜   Country：Other  

Micro/Nano Scale Thermophysical Properties and System Design

Language：Japanese  

Venue：横浜   Country：Other  

Spectral Emittance of Micro-structures of Self-assembled Sillica Particles (jointly worked)

Language：Japanese  

Venue：北九州   Country：Other  

Language：English  

Venue：伊勢志摩   Country：Other  

In-plane Thermal Conductivity of Silicon Thin Films with Periodic Micro-pores (共著）

Language：Japanese  

Venue：佐賀   Country：Other  

Fabrication of Self-organized Nano-porous Thermoelectric Thim Films

Language：Japanese  

Venue：佐賀   Country：Other  

Wavelength-selective Thermal Radiation Properties Control

Language：Japanese  

Venue：佐賀   Country：Other  

Fabrication and thermoelectric characterization of nano-crystalline n-type Bi₂Te₃

Language：Japanese  

Venue：佐世保   Country：Other  

Bi₂Te₃ thin film fabrication and thermoelectric characterization

Language：Japanese  

Venue：富山   Country：Other  

Measurements of In-Plain Thermal Conductivity and Electrical Conductivity of Porous Si Thin films

Language：Japanese  

Venue：富山   Country：Other  

Fabrication of porous film using microphase-separated structure and its application to thermoelectric devices

Language：English  

Venue：Aalborg(Denmark)   Country：Other  

Fabrication of thermoelectric materials containing conductive polymers by using printing method

Language：English  

Venue：Aalborg(Denmark)   Country：Other  

Fabrication and characterization of bismuth telluride thin films by coaxial type vacuum arc evaporation method

Language：Japanese  

Venue：東京   Country：Other  

Fabrication of nano-structured bismusth telluride thin films using micro-phase separated template film

Language：Japanese  

Venue：大阪   Country：Other  

THERMAL AND ELECTRICAL TRANSPORT PROPERTY OF POROUS SI THIN FILM

Language：Japanese  

Venue：北九州   Country：Other  

Fabrication of porous thermoelectric thin film using microphase-separated structure and its characterization

Language：Japanese  

Venue：大阪   Country：Other  

MEASUREMENT OF THERMOELECTRIC PROPERTIES OF A THIN FILM BY HARMAN METHOD

Language：Japanese  

Venue：熊本   Country：Other  

Fabrication and enhancement of thermoelectric properties using block copolymer porous film containing of heat proof unit

Language：Japanese  

Venue：熊本   Country：Other  

Enhanced Spectral Absorptance of Self-assembled Silica Particle

Language：Japanese  

Venue：熊本   Country：Other  

Bismuth Telluride Thin Films Deposited by a Coaxial Type Vacuum Arc Evaporation Method and Its Application

Language：Japanese  

Venue：福岡   Country：Other  

Printed bismuth telluride thin films and those thermoelectric properties

Language：Japanese  

Venue：福岡   Country：Other  

Measurements of In-Plane Thermal Conductivities of Si Thin Films by Periodic Laser Heating

Language：Japanese  

Venue：阿蘇   Country：Other  

In-Plane Thermal Conductivity Measurement by Harman Method

Language：Japanese  

Venue：福岡   Country：Other  

Numerical Analysis of Thermal Radiation Properties of Micro-structures of Self-assembled Silica Particles

Language：Japanese  

Venue：阿蘇   Country：Other  

Measurement and Numerical Analysis of Thermal Radiation Properties of Silica Micro-spheres Photonic Crystal

Language：Japanese  

Venue：阿蘇   Country：Other  

Fabrication of thermoelectric thin films prepared by arc plasma gun and characterization

Language：Japanese  

Venue：仙台   Country：Other  

Measurements of In-Plane Thermal Conductivites of Porous Si Thin Films by Using Laser Pulse Heating Method

Language：English  

Venue：神戸   Country：Other  

Thermoelectric Properties of In-and Ge-Doped CoSb₃-Based Skutterudites

Language：English  

Venue：神戸   Country：Other  

Higher Output Power of the Thermoelectric Module Using the High Aspect Ratio Porous Film

Language：Japanese  

Venue：名古屋   Country：Other  

Language：Japanese  

Venue：名古屋   Country：Other  

Language：Japanese  

Venue：弘前   Country：Other  

Thermal Radiation Properties of the Surface Modified Micro-particle Array

Language：Japanese  

Venue：弘前   Country：Other  

Fabrication of Nanostructured Thin Films by Micro-Phase Separation and Their Thermal Conductivities

Language：Japanese  

Venue：富山   Country：Other  

Thermal Rectifier by using Semi-Ballistic Transfer of Phonons

Language：Japanese  

Venue：仙台   Country：Other  

Strain and nanosize effects on lattice thermal conductivity in bismuth telluride based thin films

Language：Japanese  

Venue：仙台   Country：Other  

Lattice Thermal Conductivity of Nanostructured Bismuth Telluride

Language：Japanese  

Venue：富山   Country：Other  

Characterization of Thermoelectric Thin Films Deposited by Coaxial Type Vacuum Arc Evaporation Method

Language：Japanese  

Venue：福岡   Country：Other  

Measurement of Directional Thermal Radiation Properties of the Surface Modified Micro-Particle Array

Language：Japanese  

Venue：北九州   Country：Other  

Measurements of Thermal Radiation Properties of a Metal Coated Micro-particle

Language：Japanese  

Venue：福岡   Country：Other  

Fabrication and Characterization of Thermoelectric Thin Films Prepared by Vacum Arc Evaporation Method

Language：Japanese  

Venue：福岡   Country：Other  

Fabrication and Characterization of the Thermoelectric Conversion Module with Fine Particle

Language：Japanese  

Venue：北九州   Country：Other  

Measuring The Thermal Transport Peoperty of Porous Film

Language：Japanese  

Venue：福岡   Country：Other  

Numerical Analysis of Molten Pool in TIG Welding of Titanium

Language：Japanese  

Venue：浜松   Country：Other  

Thermal Radiation Properties of a Metal Coated Photonic Crystal

Language：Japanese  

Venue：浜松   Country：Other  

Evaluation of In-Plane Thermal Conductivity of PEDOT-PSS Thin Film

Language：Japanese  

Venue：浜松   Country：Other  

Thermal Conductivity of a Micro-phase Separated Thin Films

Language：Japanese  

Venue：浜松   Country：Other  

Nano-porous thermoelectric thin film and its application

Language：Japanese  

Venue：つくば   Country：Other  

Fabrication and characterization of milled thermoelectric nanoparticles

Language：Japanese  

Venue：島根   Country：Other  

Development of Low-dimensional Thermoelectric Thin Films Using a Coaxial type Vacuum Arc Evaporation Method

Language：Japanese  

Venue：東京   Country：Other  

Heat Conduction of Asymmetric Si Thin Films

Language：Japanese  

Venue：東京   Country：Other  

Thermal Transport Properties of Asymmetric Porous in Si membranes

Language：Japanese  

Venue：東京   Country：Other  

Spectral absortance of micro-particle array with defects

Language：Japanese  

Venue：東京   Country：Other  

HIGH-RESOLUTION MEASUREMENT OF SINGLE BUBBLE BOILING WITH MEMS SENSOR

Language：English  

Venue：Boston   Country：Other  

In-plane Thermoelectric device of Porous Bismuth Telluride Thin Films

Language：Japanese  

Venue：東京   Country：Other  

Thermoelectric Properties of Nanostructured Bismuth Telluride with Evaluation of Thermal Contact Resistance by 3-omega Method

Language：Japanese  

Venue：東海大学 湘南キャンパス   Country：Other  

Language：Japanese  

Venue：北九州   Country：Other  

Fabrication and Characterization of the In-plane Thermoelectric Micro Generator

Language：Japanese  

Venue：北九州   Country：Other  

Development of measurement system for thermal radiative properties

Language：Japanese  

Venue：福岡   Country：Other  

Thermoelectric properties of Bismuth Telluride prepared by nano-particles

Language：Japanese  

Venue：北九州   Country：Other  

Printed Thermoelectric Thin Film

Language：Japanese  

Venue：福岡   Country：Other  

Spectral Absorptance Control by Using Gold-Coated Micro-Particle Array

Language：Japanese  

Venue：福岡   Country：Other  

Phonon radiative heat transfer simulations for a thermal rectifier

Language：English  

Venue：Dresden, Germany   Country：Other  

Thermomechanical process improving the thermoelectric properties of polycrystalline

Language：English  

Venue：Dresden, Germany   Country：Other  

The influence of substrate temperature on thermoelectric properties of bismuth telluride thin films

Language：English  

Venue：Dresden, Germany   Country：Other  

Printable thermoelectric materials for high performance thermoelectric sheets

Language：English  

Venue：San Francisco   Country：Other  

Printable Thermoelectric Materials

Language：Japanese  

Venue：福岡   Country：Other  

Bismusth Telluride Thin Films Deposition Using a Coaxial type Vacum Arc Evaporation Method with Substrate Heating

Language：Japanese  

Venue：大阪   Country：Other  

Measurement of Thermal Radiation Properties of a Metal Coated Photonic Crystal

Language：Japanese  

Venue：仙台   Country：Other  

Language：Japanese  

Venue：大阪   Country：Other  

Boiling Heat Transfer on Micro/Nano Hybrid Surfaces Fabricated by Thermal Spray and Chemical Oxidation

Language：Japanese  

Venue：新潟   Country：Other  

Thermoelectric Properties of Organic-lnorganic Hybrid Thermoelectric Materials

Language：Japanese  

Country：Other  

B115 Boiling Heat Transfer on Micro/Nano Hybrid Surfaces Fabricated by Thermal Spray and Chemical Oxidation

Language：Japanese  

Country：Other  

29pm3-PN-51 Thermoelectric Properties of Organic-Inorganic Hybrid Thermoelectric Materials

Language：English  

Venue：Boston   Country：Other  

Screen-printed sheet type thermoelectric module for power generation

Language：Japanese  

Venue：小倉   Country：Other  

Language：Japanese  

Country：Other  

Flow boiling heat transfer on microstructured surface in minichannel

Language：Japanese  

Venue：霧島   Country：Other  

Enhancement of Pool Boiling Critical Heat Flux with Micro/Nano Hierarchica Structured Surfaces

Language：Japanese  

Venue：霧島   Country：Other  

Thermoelectric Performance of Bi₂Te₃ with Ionic Liquid

Language：Japanese  

Venue：大阪   Country：Other  

Selective solar absorber fabricated by metal organic decomposition method

Language：Japanese  

Venue：大阪   Country：Other  

Enhancement of Pool Boiling Critical Heat Flux by Superhydrophilic Surface with Micro/Nano Hierarchical Structure

Language：English  

Venue：Wuhan   Country：Other  

Bismuth telluride thin film with 10 nm thickness

Language：Japanese  

Venue：松山   Country：Other  

Language：Japanese  

Venue：松山   Country：Other  

Language：Japanese  

Venue：松山   Country：Other  

Language：Japanese  

Venue：松山   Country：Other  

Language：Japanese  

Venue：岡山   Country：Other  

Language：Japanese  

Venue：岡山   Country：Other  

Language：English  

Venue：Tokyo   Country：Other  

Thermal resistance at an organic-inorganic materials interface

Language：English  

Venue：Kitakyushu   Country：Other  

Molecular dynamics simulation on heat conduction in polyethylene

Language：English  

Venue：Tokyo   Country：Other  

Enhancement of thermal properties of silica thin films due to long range surface phonon-polaritons
Laurent主担当

Language：Japanese  

Venue：さいたま市大宮   Country：Other  

3-omega Measurement of Thermal Boundary Resistance of Polyimide-Bismuth Telluride

Language：Japanese  

Venue：さいたま市大宮   Country：Other  

Study on thermal switch using boiling and condensation heat transfer

Language：Japanese  

Venue：さいたま市大宮   Country：Other  

Measuring Contribution of Latent Heat Transfer in Pool Boiling

Language：English  

Venue：Tokyo   Country：Other  

Printed thermoelectric device

Language：English  

Venue：Pasadena, USA   Country：Other  

In-plane and cross-plane thermal conductivity of Bismuth Telluride thin film

Language：English  

Venue：Kyoto   Country：Other  

Interfacial thermal resistance between bismuth telluride and polyimide

Language：Japanese  

Venue：広島   Country：Other  

Language：Japanese  

Venue：広島   Country：Other  

Language：Japanese  

Venue：広島   Country：Other  

Language：Japanese  

Venue：つくば   Country：Other  

Language：Japanese  

Venue：大分   Country：Other  

Property Promotion of Thermal Switch using Liquid-Vapor Phase Change

Language：Japanese  

Venue：大分   Country：Other  

Development of a coaxial thermal switching device

Language：Japanese  

Venue：大分   Country：Other  

Measuring Contribution of Latent Heat Transfer in Pool Boiling

Language：Japanese  

Venue：大分   Country：Other  

3-Dimensional porous sintered body for Critical Heat Flux enhancement

Language：Japanese  

Venue：札幌   Country：Other  

Enhancement of flow boiling heat transfer in a minichannel using superhydrophilic structure

Language：Japanese  

Venue：札幌   Country：Other  

Enhancement of the Thermal Transport due to Surface Phonon-Polaritons Thermal Transport Measurement of Suspended thin films of Silicon Dioxide

Language：Japanese  

Venue：札幌   Country：Other  

Contribution of Evaporation Heat Transfer in Pool Boiling Heat Transfer

Language：Japanese  

Venue：札幌   Country：Other  

Direct electromagnetic simulation of cermet-based solar-selective absorber

Language：Japanese  

Venue：札幌   Country：Other  

Selective thermal radiative properties of a double-layered cermet printed by Metal Organic Decomposition method

Language：Japanese  

Venue：札幌   Country：Other  

3-omega Measurement of Thermal Boundary Resistance of Organic-Inorganic

Language：Japanese  

Venue：北九州市若松   Country：Other  

Pool Boiling Critical Heat Flux Enhancement by Liquid/Vapor Flow Separation Using Three-Dimensional Porous Structures

Language：Japanese  

Venue：北九州市若松   Country：Other  

Measuring microlayer thickness bottom of pool boiling bubbles by laser interferometric method

Language：Japanese  

Venue：札幌   Country：Other  

Development of an electrowetting device for thermal conductance control

Language：Japanese  

Venue：札幌   Country：Other  

Heat flux sensor with stacked structure for high resolution measurement of boiling heat transfer

Language：Japanese  

Venue：富山   Country：Other  

Thermoelectric Properties of a Coated Perovskite Thin Film

Language：Japanese  

Venue：富山   Country：Other  

Pool Boiling Critical Heat Flux Enhancement Using Three-Dimensional Porous Structures

Language：Japanese  

Venue：札幌   Country：Other  

Enhancement of flow boiling in minichannel with micro- and nano-structure

Language：English  

Country：Other  

Printed themoelectric generator

Language：Japanese  

Venue：名古屋   Country：Other  

Thermal conductivity measurement of silicon dioxide free standing thin films by hot wire method

Language：Japanese  

Venue：北九州   Country：Other  

Development of a device for thermal conductance control using liquid metal

Language：Japanese  

Venue：北九州   Country：Other  

MEMS sensor for high resolution measurement of boiling heat transfer

Language：Japanese  

Venue：北九州   Country：Other  

Pool Boiling Critical Heat Flux Enhancement by Liquid/Vapor Flow Separation Three-Dimensional Porous Structure

Language：Japanese  

Venue：北九州   Country：Other  

Enhancement of In-Plane thermal transport due to evanescent light

Language：Japanese  

Venue：北九州   Country：Other  

3-omega Measurement of Thermal Boundary Resistance of PEDOT:PSS-Bismuth Telluride

Language：Japanese  

Venue：徳島   Country：Other  

High-speed Microscope Observation of Boiling Bubble Nucleation

Language：Japanese  

Venue：徳島   Country：Other  

Enhancement of pool boiling critical heat flux by capillary wicking and liquid-vapor flow separation

Language：Japanese  

Venue：徳島   Country：Other  

Thermal Conductivity of a Printed Halide Perovskite Thin Film

Language：Japanese  

Venue：徳島   Country：Other  

Heat conduction in very thin films by surface phonon-polaritons