Species Charge and Oxidation Mechanism in the “Cathodic” Plasma Oxidation of Silicon

Abstract

This study discusses the sign of the charge of the gas phase species involved in the plasma oxidation of silicon and the oxidation mechanism itself in a system of a type previously reported in which oxidation occurs on a silicon surface facing. away from a confined plasma. Based on grid-biasing experiments, it was found that the gas-phase oxygen species responsible for oxidation are positively charged, in marked distinction to what has been proposed for plasma anodization processes. From 0 TM and Si 3~ double-marker experiments, coupled with other information, the oxidation process was found to proceed by oxygen ion transport to the Si-SiO2 interface with no outdiffusion of silicon being detected.

Growth Kinetics and Annealing Studies of the “Cathodic” Plasma Oxidation of Silicon

“…In addition, confinement of the plasma is achieved between two wafers placed on a fused quartz boat. The process that occurs in distinction to plasma anodization appears to be a form of plasma cathodization involving positive oxygen ions in both the gas phase and in the growing oxide (20). It has been reported that confining a discharge increases the plasma potential and the energy of positive ions incident on electrically isolated substrates (21).…”