CHx/PS/Si as structure for propane sensing

In the last years, the interest for a better monitoring of the air pollution has become a major key factor in the industrial development. Application of porous silicon for gas sensing devices has gained considerable attention in the last decade. Generally, porous silicon sensing properties observed are changes of electrical capacitance in the presence of gases and the quenching of photoluminescence. In this work, we report on the hydrocarbons deposition on porous silicon (PS) and the application of CHx/PS/Si as structure for propane sensing. Porous silicon layer was made from p-type Si by electrochemical anodization. The porous sample was coated with hydrocarbon groups deposited by plasma of methane. The current voltage, response time and capacitance response characteristics were studied, in order to evaluate the response and sensitivity of heterostructure devices to propane gas environment. Finally, after 1 year, the sensor preserves its features, such as sensibility, response time and stability. (c) 2004 Published by Elsevier B.V.