||Koichi Suematsu, Ultra-high sensitive (ppt) gas sensor based on the pulse heating using MEMS technique, 8th GOSPEL Workshop, 2019.06, High sensitivity and low limit of detection to volatile organic compounds (VOCs) gases are typical properties on the resistive-type semiconductor gas sensors using SnO2-based materials. In this few decades, semiconductor gas sensors were improved on the point of not only the sensitivity but also both compact and low power consumption by using the micro gas sensors equipped with the microheater and microelectrode using the MEMS (Micro Electronic Mechanical System) technique. Recently, we proposed the micro gas sensor driven in repeating mode of instantaneous heating and cooling (pulse-driving) [1,2]. According to the pulse-driving mode, VOCs gases can introduce into the sensing layer during cooling period, and it improves the utilize efficiency of the sensing layer. Thus, in this study, we aimed to improve the sensor response in low concentration of VOCs gases, SnO2 based gas sensor was driven under pulse-driving mode with monotonic and two-step heating..
||Kengo shimanoe, Koichi Suematsu, Ken Watanabe, Consideration for oxygen adsorption species on SnO2 semiconductor gas sensors, 8th GOSPEL Workshop, 2019.06.
||Ken Watanabe, Shingo Ide, Koichi Suematsu, Kengo Shimanoe, Amperometric-type gas sensor, Oxide ionic conductor, c-axis-oriented La9.33Si6O26, 22th Solid State Ionics, 2019.06.
||Takahito Kanda, Ken Watanabe, Shingo Ide, Koichi Suematsu, Kengo Shimanoe, Lowering the operating temperature of amperometric NO2 sensor using c-axis oriented La9.66Si5.3B0.7O26.14 electrolyte , 22th Solid State Ionics, 2019.06.
||Koichi Suematsu, Wataru Harano, Tokiharu Oyama, Nan Ma, Ken Watanabe, Kengo Shimanoe, ULTRA-HIGH SENSITIVE GAS DETECTION USING PULSE-DRIVEN MEMS SENSOR BASED ON TIN DIOXIDE, 18th International Symposium on Olfaction and Electronic Nose (ISOEN), 2019.05.
||Koichi Suematsu, Sun Yongjiao, Ken Watanabe, Maiko Nishibori, Kengo Shimanoea, Analysis of Oxygen Adsorption on Surface of Metal Oxide to Understand Sensing Mechanism of Semiconductor Gas Sensors, 12th Asian Conference on Chemical Sensors, 2017.11.
||Koichi Suematsu, Nano-Scale Particles Design of Metal Oxide Semiconductor Gas sensors for Environmental Protection, The 18th International Symposium on Eco-materials Processing and Design (ISEPD 2017), 2017.02, To detect the harmful gases in atmosphere using gas sensors is important for environment protection. Recently, the building gas sensors with high performance such as high gas sensitivity, rapid response and recovery, gas selectivity, and humidity resistance are strongly required. Resistive-type semiconductor gas sensors, especially SnO2-based gas sensors, are attracting the most attention because of their high potentiality. So far, we have reported that the introduction of three key factors, receptor function, transducer function and utility factor, to material design of sensors gives ultrahigh sensitivity in ppb level. However, the decrease in electric resistance by water vapor poisoning is most fundamental problem for practical use, because atmospheric environment includes water vapor and also the amount is different in each time and place. Recently, we tried to overcome such weak-point on SnO2-based gas sensors from viewpoint of materials design. For example, the decrease in electric resistance by water vapor poisoning can be improved by surface Sb substitution. Such materials design can raise the sensor performances and allow the practical use for environmental protection..
||Koichi Suematsu, Takanori Honda, Masayoshi Yuasa, Tetsuya Kida, Kengo Shimanoe, Noboru Yamazoe, Effect of foreign metal doping on the gas sensing behaviors of SnO2-based gas sensor, International Conference on Multi-functional Materials and Structures, 2008.07.