Fast Response and Recovery of Porous Silicon based Gas Sensor for Detection of Benzene Gas by Impedance Metric Method
This work reports the fabrication of porous silicon (PS) based gas sensor and its detection mechanism for
benzene. The resistance of the sensor changes with concentration of gas. This transduction mechanism was tested using
precalibrated gas injection method. Nanopores were developed on p type substrates by HF based wet electrochemical
etching. The presence of nanopores network on silicon was confirmed and its morphology was studied by SEM imaging and
their uniform distribution was observed. Impedance spectroscopy was done at room temperature and increased grain
boundary resistance was observed for increasing benzene gas concentration range of 2-6 ppm.
Keywords- PS, SEM image, Impedance spectroscopy.