Method for formation of an isolating oxide layer

摘要

In a method for the formation of an isolating oxide layer on a silicon substrate, an anti-nitridation layer is formed on a silicon substrate at locations where isolating oxide is desired. The anti-nitridation layer has openings therethrough which expose the silicon substrate at locations where isolating oxide is not desired. A thin silicon nitride layer is selectively grown at the locations where isolating oxide is not desired by nitridation of the exposed silicon substrate. Isolating oxide is then selectively grown at the locations where isolating oxide is desired. The thin silicon nitride layer inhibits oxide growth at the locations where isolating oxide is not desired. The method reduces "bird's beak" formation and is particularly applicable to high density IGFET devices.