Fabrication of E Nose Sensor for Detection of Butane Gas by using Nano Porous Silicon

This work reports the manufacture of a Nano porous silicon (NPS) gas sensor and its butane detection mechanism. The sensor's resistance changes with the gas concentration. This transduction mechanism has been tested using a gas injection precalibration method. Nanopores were developed using HF- based wet electrochemical etching on p- type substrates. The presence of nanoporeson silicon has been confirmed and its morphology has been studied by SEM imagery and its uniform distribution has been demonstrated. Impedance spectroscopy was performed at room temperature and increased grain boundary resistance was observed for a range of 2-6 ppm of butane gas.