Reduction of residual stress in SiO_2-matrix silicon nano-crystal thin films by a combination of rapid thermal annealing and tube-furnace annealing

摘要

In this work. SRO thin films were prepared by magnetron sputtering and comveried 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 residua] stress in the Si-NC. thin films alter RTA at 1100 and 1200 ℃ were determined as 2.41 and 1.1.87 GPa. respectively, and the following lube-furnace annealing can obviousiy dvreasc the residual stress. The residual stress decreased with increasing annealing temperature andtime. The following tube-furnace annealing at 1100 ℃ for 60min and 1000℃ for 180 min reduced the residual stress to 1.46 and 1 GPa, respectively, for ihe Si-NC thin films with prior RTA at 1200 ℃. The reduction of residual stress was ascribed to the larger density of extended delects and the lower surface-to-volume ratio of the thin films.