Method for depositing silicon oxide layer on silicon substrate utilized to form gate of e.g. N-channel metal-oxide-semiconductor transistor, involves forming silicon layer over silicon-germanium to deposit oxide layer on substrate

摘要

The method involves forming a thin silicon layer (30) with thickness of about 0.1-1 nanometer over silicon-germanium such that a silicon oxide layer (32) is deposited on a substrate (21) i.e. silicon substrate, by chemical vapor deposition. The substrate is formed of a silicon area and a silicon-silicon-germanium area consisting of a thin layer (29) whose upper surface lies at a same level as an upper surface of the silicon. The thin silicon layer is formed in an epitaxy chamber that is utilized for forming the silicon-germanium area. Hydrogen chloride gas is added while reducing temperature.