Sensing mechanism of hydrogen gas sensor based on RF-sputtered ZnO thin films
Sensing mechanism of hydrogen gas sensor based on RF-sputtered ZnO thin films
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DOI：
10.1016/j.ijhydene.2010.02.006
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发表时间：
2010-05-01
影响因子：
7.2
通讯作者：
Aziz, A. Abdul
中科院分区：
文献类型：
--
作者：
Al-Hardan, N. H.;Abdullah, M. J.;Aziz, A. Abdul
研究了射频溅射ZnO薄膜在200-1000 ppm范围内的氢（H-2）气敏机理。作为工作温度的函数的I-V特性证明了传感器的接触的欧姆行为。薄膜的复阻抗谱（IS）显示出一个单周期的直径随着温度的升高而收缩。这些数据的最佳拟合证明，器件结构可以建模为一个单一的电阻电容等效电路。提出了ZnO传感器的导电机理是由表面反应控制的。在200 ppm ~ 1000 ppm范围内，随着氢浓度的增加，阻抗谱的半径也减小。(C)2010由Elsevier Ltd代表T. Nejat Veziroglu。
The mechanism of hydrogen (H-2) gas sensing in the range of 200-1000 ppm of RF-sputtered ZnO films was studied. The I-V characteristics as a function of operating temperature proved the ohmic behaviour of the contacts to the sensor. The complex impedance spectrum (IS) of the ZnO films showed a single semicircle with shrinkage in the diameter as the temperature increased. The best fitting of these data proved that the device structure can be modelled as a single resistance-capacitance equivalent circuit. It was suggested that the conductivity mechanism in the ZnO sensor is controlled by surface reaction. The impedance spectrum also exhibited a decreased in semicircle radius as the hydrogen concentration was increased in the range from 200 ppm to 1000 ppm. (C) 2010 Published by Elsevier Ltd on behalf of Professor T. Nejat Veziroglu.