The concentration of polar gases in the measuring chamber affects the way of employing photo-electromotive forces on the heterojunction between porous silicon thin layer and crystalline silicon wafer. Electrochemical etching on a p-type silicon wafer produced the porous silicon thin layer. To this porous layer, a gas and light transparent electrical contact was created. Controlling the intensity of illumination light can improve photo-EMF sensitivity corresponding to a wide range of gas concentrations. When the magnitude of the gas concentration matches to the optimal intensity of the illuminating light, the measurement error is the smallest. The study used NI LabVIEW-engineered modules for automatic control to increase measurement precision across a wide spectrum of gases. This intelligent gas sensors system, which uses modern wireless network technology, could be valuable in the chemical sector for real-time gas detection. Ammonia, acetone, ethanol, and mercaptoethanol were all tested using photovoltaic gas sensors.
Department of Physics, Odessa State Academy of Civil Engineering and Architecture, Odessa, 65029, Ukraine. and Electrical and Computer Engineering Division, Hanyang Institute of Technology, Hanyang University, Seoul 133-791, Republic of Korea.
Kae Dal Kwack
Electrical and Computer Engineering Division, Hanyang Institute of Technology, Hanyang University, Seoul 133-791, Republic of Korea.