Karimov K S, Qazi I, Khan T A, Draper P H, Khalid F A, Mahroof-Tahir M
Physical Technical Institute, Aini St. 299/1, Dushanbe 734063, Tajikistan.
Environ Monit Assess. 2008 Jun;141(1-3):323-8. doi: 10.1007/s10661-007-9898-5. Epub 2007 Sep 12.
In this investigation properties of organic semiconductor copper phthalocyanine (CuPc) capacitive humidity and illumination sensors were studied. Organic thin film was deposited by vacuum evaporation on a glass substrate with silver surface-type electrodes to form the Ag/CuPc/Ag sensor. The capacitance of the samples was evaluated at room temperature in the relative humidity range of 35-92%. It was observed that capacitance of the Ag/CuPc/Ag sensor increases with increase in humidity. The ratio of the relative capacitance to relative humidity was about 200. It is assumed that in general the capacitive response of the sensor is associated with polarization due to absorption of water molecules and transfer of charges (electrons and holes). It was observed that under filament lamp illumination of up to 1,000 lx the capacitance of the Ag/CuPc/Ag photo capacitive detectors increased continuously by 20% as compared to dark condition. It is assumed that photo capacitive response of the sensor is associated with polarization due to transfer of photo-generated electrons and holes. An equivalent circuit of the Ag/CuPc/Ag capacitive humidity and illumination sensor was developed. Humidity and illumination dependent capacitance properties of this sensor make it attractive for use in humidity and illumination multi-meters. The sensor may be used in instruments for environmental monitoring of humidity and illumination.
在本研究中，对有机半导体铜酞菁（CuPc）电容式湿度和光照传感器的性能进行了研究。通过真空蒸发将有机薄膜沉积在带有银表面型电极的玻璃基板上，以形成Ag/CuPc/Ag传感器。在室温下，于35 - 92%的相对湿度范围内对样品的电容进行了评估。观察到Ag/CuPc/Ag传感器的电容随湿度增加而增大。相对电容与相对湿度的比值约为200。一般认为，传感器的电容响应与水分子吸收和电荷（电子和空穴）转移引起的极化有关。观察到在高达1000 lx的白炽灯照明下，与黑暗条件相比，Ag/CuPc/Ag光电容探测器的电容持续增加了20%。一般认为，传感器的光电容响应与光生电子和空穴转移引起的极化有关。开发了Ag/CuPc/Ag电容式湿度和光照传感器的等效电路。该传感器的湿度和光照依赖电容特性使其在湿度和光照万用表中具有吸引力。该传感器可用于湿度和光照环境监测仪器。
