, Hamide Eskandari Torbaghan,
Volume 11, Issue 3 (2-2011)
Abstract
This study presents the electric behavior of sandwich devices based on porous silicon (PS) thin films with Au/Ps/Si/Cu structure when the material’s surface is exposed to different gases. PS thin films were fabricated by the electrochemical anodization method of Si–c (100) substrates with resistivity 1.4-2.6 Ωcm. Samples were anodized in a solution of HF (48%), C2H5OH (99.98%) and distilled water with different current densities, etching time(t) and anodization length(L). They exhibit a different behavior after anodization process. This behavior can be explained by band gap measurement on graph. In this research, measurement of I-V and I-T characteristics were carried out at different conditions, in the presence of O2, N2 and Co2 gases for gas sensing construction. The best response to gas exposure belonged to these parameters: current density= 20 mA/cm2 ،t = 1800 S ، PH = 1.869 and L = 4 cm.
