Properties of a-Si1-xCx : H thin films deposited from the organosilane triethylsilane

We deposited carbon-rich a-Si1-xCx:H thin films from the liquid organosilan e source Triethylsilane (C2H5)(3)-Si-H (TrES) in a PECVD process at 13.56 M Hz. These films generally show a photoluminescence in the visible spectral range when excited with ultraviolet light. By increasing the substrate temp erature from room temperature up to 300 degrees C we can red shift the PL p eak energy and also the optical Tauc gap. Furthermore, an increase in the f ilm density and correspondingly in the refractive index is observed. FTIR m easurements show that these films have a polymer-like character for all tem peratures under investigation. The hydrogen concentration is calculated fro m the stretching modes of CHn and SiHn groups, respectively, and is shown t o decrease with substrate temperature. We also show that the amount of hydr ogen bonded to carbon decreases with respect to that bonded to silicon with substrate temperature. (C) 1999 Elsevier Science S.A. All rights reserved.