Regulation of the morphology and photoluminescence of silicon nanowires by light irradiation

Abstract

We successfully synthesized porous Si nanowire arrays with excellent photoluminescence properties. We found that light irradiation not only promotes the formation of the Si nanowire arrays, but also enhances their porosity. The porous Si nanowire arrays have excellent photoluminescence properties. On moderately doped substrates the porous Si nanowire arrays display a luminescence intensity 11 times greater than that of arrays prepared on the same substrate without light irradiation; on highly doped substrates the luminescence intensity is increased by 1.8 times from that of arrays prepared on the same substrate without light irradiation. In addition, the photoluminescence properties of the as-prepared Si nanowire arrays are stable. These porous Si nanowire arrays may have potential applications in gas sensors, in photocatalysis and in solar cells.