Water-vapor-doped Graphene for Temperature Sensor

• Main Authors: Wei-Ting Lin, 林威廷
• Other Authors: 張所鋐
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/78267230544708567531

碩士 === 國立臺灣大學 === 機械工程學研究所 === 103 === Graphene was taken as the sensing element to design a new temperature sensor in this study. Temperature sensor was made by the few-layer graphene which was grown by chemical vapor deposition (CVD) and then transferred to glass as the transfer substrate. We measured the relationship between temperature and resistance under normal atmospheric environment, vacuum environment and water vapor environment with hydrogen-doping preprocess respectively. Then we calculated temperature coefficient of resistance (TCR) of these cases and analyzed their temperature sensing behaviors. The experimental result indicates that the graphene has poor temperature sensing property under normal atmospheric environment. Intrinsic graphene under vacuum environment is negative temperature coefficient (NTC) and its sensitivity is stable. Lightly-vapor-doped graphene has NTC as well. However, heavily-vapor-doped graphene is positive temperature coefficient (PTC). And the |TCR| or the sensitivity of lightly-vapor-doped graphene increases as temperature rises. Furthermore, hydrogen doping will increase absorption capacity and absorption rate of graphene, which causes larger |TCR|, about 0.35 %/℃ at 65 ℃.