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

Direct bonding of lithium tantalate to silicon at room temperature by using a self-sputtered bonding method

DOI： 10.7567/1347-4065/ab0ffd

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

Cu/SiO2 hybrid bonding obtained by surface-activated bonding method at room temperature using Si ultrathin films

DOI： 10.1016/j.mne.2018.11.004

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

Cu/SiO2 Hybrid Bonding at Room Temperature by Surface Activated Bonding Method Using Si Ultrathin Films

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

Direct Bonding of Oxide Materials and Si at Room Temperature Using Self-sputtered Bonding Method

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

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

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

Characterization of p-ZnTe/n-ZnO heterojunction interface prepared by direct bonding technology

DOI： 10.1541/ieejeiss.136.1761

Language：English   Publishing type：Research paper (international conference proceedings)  

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

The bonding of metal electrodes and insulator hybrid interfaces is one of the key techniques in three-dimensional integration technology. Metal materials such as Cu or Al are easily directly bonded by surface activated bonding at room temperature, but insulator materials such as SiO2 or SiN are not. Using only Si ultrathin films, we propose a new bonding technique for SiO2/SiO2 bonding at room temperature. Two SiO2 surfaces, on which Si thin films were deposited, were contacted in vacuum. We confirmed that the thickness of the layer was about 7 nm by transmission electron microscopy observation and that the layer was non crystalline by electron energy loss spectroscopy analysis. No metal material was found in the bonding interface by energy-dispersive X-ray spectroscopy analysis. The surface energy was about 1 J/m(2), and the bonding strength was more than 25 MPa. This bonding technique was successfully realized to enable SiO2/SiO2 bonding without a metal adhesion layer. (C) 2016 The Japan Society of Applied Physics

DOI： 10.7567/JJAP.55.026503

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

Bonding Technique of SiO2/SiO2 Bonding at Room Temperature by SAB Method for 3D Integration Technology

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

In this study, Co and Al ions co-doped ZnO nanoparticles (Zn(Al, Co) O NPs) were prepared by our original chemical preparation method. The obtained samples prepared by this method, were encapsulated in amorphous SiO2. X-ray diffraction (XRD) results showed Zn(Al, Co) O NPs had a single-phase nature with hexagonal wurtzite structure. These particle sizes could be controlled to be approximately 30 nm. We investigate the effect that the increase in the carrier has on the magnetization by doping Al to Co-doped ZnO NPs. The local structures were qualitatively analyzed using X-ray absorption fine structure (XAFS) measurements.

DOI： 10.1063/1.4941203

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

Cu/Cu bonding and SiO2/SiO2 bonding by surface activated bonding at room temperature for hybrid bonding technique

DOI： 10.1299/transjsme.15-00408

Language：Japanese  

Study on the hybrid bonding technology using the surface activated bonding at room temperature for 3D integration

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

Characterization of Cu/Cu bonding interface prepared by surface activated bonding at room temperature

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

Effect of bonding pressure on the strength of Cu/Cu direct bonding by surface activated method

DOI： 10.1541/ieejsmas.134.284

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

The metal bonding is a key technology in the processes for the microelectromechanical systems (MEMS) devices and the semiconductor devices to improve functionality and higher density integration. Strong adhesion between surfaces at the atomic level is crucial; however, it is difficult to achieve close bonding in such a system. Cu films were deposited on Si substrates by vacuum deposition, and then, two Cu films were bonded directly by means of surface activated bonding (SAB) at room temperature. The two Cu films, with the surface roughness Ra about 1.3nm, were bonded by using SAB at room temperature, however, the bonding strength was very weak in this method. In order to improve the bonding strength between the Cu films, samples were annealed at low temperatures, between 323 and 473 K, in air. As the result, the Cu-Cu bonding strength was 10 times higher than that of the original samples without annealing.

DOI： 10.1063/1.4866626

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

Cu/Cu direct bonding by surface activated method

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

A detailed and quantitative motivation for the necessity of room temperature (RT) bonding for wafer level packaging of silicon micro-mirrors will be given. Results on RT 6 inch wafer bonding with vacuum encapsulation on test structures are presented. Structured as well as unstructured wafers have been bonded at RT using a Mitsubishi Heavy Industries bonder. Unstructured wafers were used for the determination of the bonding strength, whereas the structured wafers were used for the evaluation of vacuum level and its stability with time. © 2012 Springer-Verlag Berlin Heidelberg.

DOI： 10.1007/s00542-012-1703-x

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

Surface activated bonding (SAB) by Ar beam sputter etching has been proved to have ability to bond various semiconductor wafers at room temperature. In this paper, we report SAB of oxide wafers. Various oxide wafers were successfully bonded to Si wafers by SAB. Strong bonding equivalent to bulk strength was achieved without any heat treatments. Among the oxide wafers tested, SiO2 was only a material which was not form strong bond with Si at room-temperature. On the other hand, strength of oxide-to-oxide bonding by SAB was not so strong as bulk materials and was largely dependent on the bonded oxide materials. In case of oxideto-oxide bonding, SiO2 was again difficult to bond. Deposited thin oxide film such as TiO2 could be bonded by SAB and was effective to improve bonding properties. In summary, oxide wafers were successfully bonded by SAB at room-temperature, however its strength depends on oxide materials. © The Electrochemical Society.

DOI： 10.1149/1.2982908

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

An n-type phosphorus (P)-doped epitaxial diamond film with high conductivity was grown on a nitrogen (N)-doped or a boron (B)-doped C(001) substrate by gas-source molecular beam epitaxy (GSMBE) using methane and tri-n-butylphosphine. On the N-doped substrate, the electrical conductivity of the P-doped diamond film was measured to be 0.33 (Omega.cm)(-1) at RT with an activation energy of 0.12 eV. The Hall measurement showed it-type conduction and a carrier concentration of 1.6 x 10(18) cm(-3) at 400 degrees C, which was comparable to the P concentration determined by secondary ion mass spectrometry. These indicate the formation of a shallow P donor level with high electrical activation efficiency. On the B-doped substrate, we obtained the p-n characteristics with a rectification ratio of similar to 10(3) at 10 V. Electroluminescence (EL) in the visible and ultraviolet ranges was observed from the p-n junction at RT. Under the forward-bias condition, the EL spectrum showed both a main broad peak at 540 nm with two shoulders at 495 nm and 620 nm, and a peak at 270 nm, which were interpreted to be the transition between energy levels previously reported for B and N impurities. Therefore, the EL was concluded to be emitted from the B-doped substrate to which electrons were injected from the n-type epitaxial film.

Event date： 2010.8

Language：English  

Country：Other  

Annealing Effect of Cu-Cu Surface Bonding at Room Temperature

Language：Japanese  

Country：Other  

Language：Japanese  

Country：Japan  

Language：English  

Country：Other  

Room-Temperature Bonding of Oxide Wafers by Ar-beam Surface Activation

Language：English  

Country：Other  

Cu-Cu Direct Bonding Achieved by Surface Activated Bonding at Room Temperature

Language：Japanese  

Country：Other  

Language：Japanese  

Country：Other  

Language：English  

Country：Other  

Surface analysis of Cu films for hybrid bonding by surface activated bonding at room temperature

Language：Japanese  

Country：Other  

Language：Japanese  

Country：Other  

Language：English  

Country：Other  

Bonding of SiO2 and SiO2 at Room Temperature Using Si Ultrathin Film

Language：Japanese  

Country：Other  

Language：Japanese  

Country：Other  

Language：Japanese  

Country：Other  

Direct Bonding of SiO2/Si at Room Temperature using Self-Sputtered Bonding Method

Language：Japanese  

Country：Japan  

Language：Japanese  

Country：Other  

Direct Bonding of LiTaO3/Si at Room Temperature Using Self-sputtered Bonding Method

Language：Japanese  

Country：Other  

Direct Bonding of Oxide Materials and Si at Room Temperature Using Self-sputtered Bonding Method

Language：Japanese  

Country：Other  

Cu/SiO2 Hybrid Bonding at Room Temperature by Surface Activated Bonding Method Using Si Ultrathin Films

Type：Peer review 

Type：Competition, symposium, etc. 

Type：Peer review 

Number of peer-reviewed articles in Japanese journals：1

Type：Competition, symposium, etc. 

Type：Peer review 

Number of peer-reviewed articles in Japanese journals：2

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc.