Ultra-thin silicon-oxide films by sputter-deposition and their applicationto high-quality poly-Si TFTS

This paper describes ultra - thin high - quality silicon oxide (SiO2) films deposited at low temperature by sputtering from a SiO2 target in an oxygen -argon mixture. SiO2 films up to a thickness of 6.5 nm are successfully for med on polycrystalline silicon (poly-Si) films which have a surface roughne ss of several nanometers. The SiO2 films show electrical properties with a sufficiently high breakdown voltage and low leakage current which are compa rable with the electrical properties of the thermally grown SiO2 film on si ngle-crystalline Si at high temperature. Moreover, both n- and p-channel po lycrystalline silicon thin him transistors (poly-Si TFTs) with ultra-thin s puttered SiO2 films show excellent characteristics. (C) 1998 Elsevier Scien ce Ltd. All rights reserved.