Optical Studies on Oxidized Porous Silicon

Abstract

The porous silicon (PSi) samples were prepared by photo‐electrochemical anodization method. As‐prepared and oxidized PSi samples were studied using photoluminescence spectrometer and Raman spectrometer. PSi samples were prepared at 40 and 50 mA/cm2 of current density for 20 minutes. As‐prepared sample was kept in a tight chamber as a control sample. The oxidation process used to prepare oxidized PSi which is PSi placed in the oxidation chamber for various time exposition. The products samples were analyzed by PL spectra which have shown the peak positions and peak intensity changes with level of oxidation. The peaks shown shifted to higher energies after oxidized and FWHM becomes smaller compared to as‐prepared samples. Raman spectra of PSi have shown the significant differences between as‐prepared PSi and oxidized PSi samples that change the line shape become more symmetry shape. Photoluminescence (PL) and Raman spectrum used to estimate the size of nanocrystallites of as‐prepared PSi and oxidized PSi.