Study of Gallium-based Thin Film Oxide Device for High Temperature Oxygen Sensor

• Main Authors: Wen, Shih-Chih, 温時智
• Other Authors: Yarn, Kao-Feng
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/68417215021413979106

碩士 === 遠東科技大學 === 機械工程研究所在職專班 === 104 === Novel oxygen gas sensor based on gallium oxide thin film operated at high temperature above 6000C has been analyzed in this thesis. First, gallium oxide thin films have been deposited on silicon substrate by sputtering method. Grain sizes of the material are dependent on different sputtering conditions and investigated by atomic force microscope (AFM). In addition, a new V-shaped surface chemical-etched Pt/gallium oxide/Pt semiconductor sandwich structure has been successfully fabricated for increasing the oxygen sensing area. Under room temperature (300K) and oxygen exist conditions, their current-voltage (I-V) characteristics are investigated. In the other hand, I-V characteristics of the V-shaped gallium oxide device under different oxygen (O2) concentration are also measured. Due to the enlarged oxygen sensing area, high sensitivity, short response time and significant increase in output resistance are observed. From experiment, under the equipment temperature about 8300C and changeable oxygen gas in nitrogen, a large variation of dynamic variation resistance 74KΩ is obtained. Finally, a simple Wheatstone bridge circuit is successfully used to get the O2 voltage-concentration transfer plot.