Wu Chiu-Hsien, Jiang Guo-Jhen, Chang Kai-Wei, Deng Zu-Yin, Li Yu-Ning, Chen Kuen-Lin, Jeng Chien-Chung
Institute of Nanoscience, National Chung Hsing University, Taichung 402, Taiwan.
Department of Physics, National Chung Hsing University, Taichung 402, Taiwan.
Sensors (Basel). 2018 Jan 9;18(1):163. doi: 10.3390/s18010163.
In this study, the sensing properties of an amorphous indium gallium zinc oxide (a-IGZO) thin film at ozone concentrations from 500 to 5 ppm were investigated. The a-IGZO thin film showed very good reproducibility and stability over three test cycles. The ozone concentration of 60-70 ppb also showed a good response. The resistance change (Δ) and sensitivity () were linearly dependent on the ozone concentration. The response time (), recovery time (), and time constant (τ) showed first-order exponential decay with increasing ozone concentration. The resistance-time curve shows that the maximum resistance change rate (dRg/dt) is proportional to the ozone concentration during the adsorption. The results also show that it is better to sense rapidly and stably at a low ozone concentration using a high light intensity. The ozone concentration can be derived from the resistance change, sensitivity, response time, time constant (τ), and first derivative function of resistance. However, the time of the first derivative function of resistance is shorter than other parameters. The results show that a-IGZO thin films and the first-order differentiation method are promising candidates for use as ozone sensors for practical applications.
在本研究中，研究了非晶铟镓锌氧化物（a-IGZO）薄膜在500至5 ppm臭氧浓度下的传感特性。a-IGZO薄膜在三个测试周期内表现出非常好的重现性和稳定性。60-70 ppb的臭氧浓度也显示出良好的响应。电阻变化（Δ）和灵敏度（）与臭氧浓度呈线性相关。响应时间（）、恢复时间（）和时间常数（τ）随着臭氧浓度的增加呈一阶指数衰减。电阻-时间曲线表明，吸附过程中最大电阻变化率（dRg/dt）与臭氧浓度成正比。结果还表明，在高光强度下，在低臭氧浓度下快速稳定地传感效果更好。臭氧浓度可以从电阻变化、灵敏度、响应时间、时间常数（τ）和电阻的一阶导数函数推导得出。然而，电阻一阶导数函数的时间比其他参数短。结果表明，a-IGZO薄膜和一阶微分法有望成为实际应用中用作臭氧传感器的候选材料。
