Fabrication and characterization of porous silicon based alcohol gas sensor

Abstract

The present evaluation editorial is dedicated to thc analysis of the newlineproblems related to the design and development of alcohol gas sensors based on newlinePorous Silicon (PS). The idiosyncrasies of the semiconductor porosification by newlineanodic etching and the philosophies of gas sensor design based on PS, including newlinegas sensor construction and main operating characteristics are considered in this newlineresearch work. It is shown that the surrounding atmosphere influences the newlineparameters of PS such as refractive index, the intensity of photoluminescence, newlineelectroconductivity, dielectric constant, and surface potential which might be newlineused to design gas sensor. newlineBy focusing on the conducted analysis, it can be concluded that PS has a great newlinepotential for gas sensor applications. newlineInitially, the research work started with a simulation of DC analysis of newlinePS-based gas sensor with Gold (Au) contact for better performance. It inspects newlinethe effects of porous silicon thickness with optimum placement of contact on the newlinesurface of PS by using CAD tool. The optimal condition for the gas sensing newlinemechanism is derived for 100um thickness of the PS which requires the distance newlinebetween the electrical contacts from 20 um - 50um to make the interface current newlinethrough Silicon substrate as negligible. newlineAfter successfully completing the design and simulation of newlinePS-based gas sensor, the formation porous silicon has been done. PS is formed newlineby electro-chemical etching of silicon in HF-based electrolyte. The porosity and newlinedepth (thickness) of as-formed Micro and Macro porous silicon were determined newlineby gravimetric method. Experiments have been carried out to understand the newlineeffect of formation parameters such as HF concentration, current density ,and newlineanodization time on porosity and depth of PS. newline