Reduction of residual stress in SiO2‐matrix silicon nano‐crystal thin films by a combination of rapid thermal annealing and tube‐furnace annealing

Abstract

AbstractIn this work, SRO thin films were prepared by magnetron sputtering and converted to Si nano‐crystals (Si‐NCs) by rapid thermal annealing (RTA). Further tube‐furnace annealing was performed on the Si‐NC films in order to reduce residual stress. The residual stress in the Si‐NC thin films after RTA at 1100 and 1200 °C were determined as 2.41 and 1.87 GPa, respectively, and the following tube‐furnace annealing can obviously decrease the residual stress. The residual stress decreased with increasing annealing temperature and time. The following tube‐furnace annealing at 1100 °C for 60 min and 1000 °C for 180 min reduced the residual stress to 1.46 and 1 GPa, respectively, for the Si‐NC thin films with prior RTA at 1200 °C. The reduction of residual stress was ascribed to the larger density of extended defects and the lower surface‐to‐volume ratio of the thin films.