Existence of a universal low-energy tail in the photoluminescence of a-SiC: H alloys
Journal
Solid State Communications
Journal Volume
79
Journal Issue
2
Pages
175-177
Date Issued
1991
Author(s)
Abstract
Photoluminescence measurements have been performed in a-SiC: H alloys prepared by the plasma decomposition of SiH4 and C2H4 gas mixture. It is found that the shift of the peak of the photoluminescence spectrum with increasing the gas flow ratio x ( = 2[C2H4]/(2[C2H4] + [SiH4])) parallels the widening of the optical gap. For x ≤ 0.6 the samples show that the photoluminescence efficiency in the low-energy tail is insensitive to the gas flow ratio. Together with the similar results observed in a-SiGe: H and a-Si: H alloys by Gal et al. [Phys. Rev. B31, 4060 (1985)], it calls for re-examination of the currently accepted model for the dominant-photoluminescence process in good quality a-Si: H. The explanation adapted from the Brodsky's quantum well model is consistent with the experimental facts. © 1991.
SDGs
Other Subjects
Photoluminescence--Measurements; Semiconducting Silicon Compounds; Low-energy tails; Optical gaps; Silicon and Alloys
Type
journal article