Atomic layer deposition of silicon oxide thin films by alternating exposures to Si(2)Cl(6) and O(3)

Abstract

We report the process for the atomic layer deposition (ALD) of silicon dioxide thin films on a silicon wafer by alternating exposures to Si(2)Cl(6) and O(3). The deposition was governed by a self-limiting ALD reaction at 403-453 degrees C, and the growth rate at 453 degrees C was saturated at 0.32 nm/cycle for Si(2)Cl(6) exposures over 1x10(8) L. However, at 471 degrees C or higher temperatures, the thermal decomposition of Si(2)Cl(6) and the oxidation of Si by O(3) dominated the deposition, resulting in high growth rates and Si-rich films. The ALD films exhibited excellent electrical properties that were equivalent to those of low-pressure chemical vapor deposition films. (C) 2008 The Electrochemical Society.