| || Effect of Different Chemical Environment on Porous Silicon
Author : Gupta, Amita;Jain, Alok;Jain, V.K.
Source : Defence Science Journal ; Vol:50(1) ; 2000 ; pp 87-94
Subject : 620.1 Material Science and Technology
Keywords : Porous silicon;Chemical vapours
Abstract : Properties of porous silicon (PS) are found to be sensitive towards different chemical environment. Because of its large surface area, it is highly reactive and can adsorb chemical vapours. The present study shows that photoconductivity and photoluminescence (PL) properties are changed significantly in the presence of acetone, ammonia and steam vapours and can be used to identify and sense these chemical environment. These results also suggest that the molecules adsorbed on the pores change the transport mechanism of carriers in PS, leading to increase or decrease in conductivity. On the other hand, surface states on the enormous PS surface are modified under different chemical environment, leading to change in visible PL.