Isolation Technique Using Oxygen Implantation
Original Publication Date: 1985-Apr-01
Included in the Prior Art Database: 2005-Feb-18
This article relates generally to a process for fabricating integrated circuits and more particularly to a process for electrically isolating individual devices in such integrated circuits. Still more particularly the article relates to a selective isolation technique wherein the thermal oxide growth rate at regions with implanted oxygen is enhanced to reduce bird's beak in a fully recessed oxide structure (ROX). Fig. 1 shows a cross-sectional view of a semiconductor substrate 1 after it has been subjected to a reactive ion etching (RIE) step. To obtain the structure of Fig. 1, layers 2,3 of silicon nitride and silicon dioxide, respectively, are chemically vapor deposited (CVD) on a layer 4 of silicon dioxide, otherwise characterized in Fig. 1 as pad oxide.