Silicon oxide formation for TFTs using humid ozone-enriched gas ambient at low temperature

Abstract

Humid ozone-enriched ambient, created by bubbling (O/sub 3/+O/sub 2/) gas in H/sub 2/O or H/sub 2/O/sub 2/, enhanced the silicon oxide growth on a Si substrate at 250/spl deg/C. The film thickness was controllable with a high growth rate of 1.4 /spl Aring//min. The XPS data shows that the oxide layer on the Si(111) has the same transition layer structure as thermal SiO/sub 2/ film. By combination with a short-time treatment at higher temperature (below 500/spl deg/C), the electrical characteristics of SiO/sub 2/ thin films were improved. The operation of polycrystalline Si thin film transistors using this oxide film indicates that the new growth method is applicable for low-temperature device fabrication.