Method and structure for an oxide layer overlaying an oxidation-resistant layer

US6297092A · kind A · utility

Assignee

• Micron Technology, Inc. · US

Inventors

• Paul Rudeck · Boise, US
• Kelly Hurley · Boise, US

Key dates

• Filing date: Dec 2, 1998
• Grant date: Oct 2, 2001
• Expiry date: Dec 2, 2018

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/035

Abstract

A method used during the formation of a semiconductor device such as a flash memory device comprises the steps of forming a floating gate layer over a semiconductor wafer substrate then forming a first oxide layer over the floating gate layer. An oxidation-resistant layer such as a nitride layer is formed over the first oxide layer wherein a first portion of the oxidation-resistant layer oxidizes more readily than a second portion of the oxidation-resistant layer. To accomplish this the first portion of the oxidation-resistant layer can be formed to have a higher silicon concentration than the second portion. The first portion of the oxidation-resistant layer is oxidized to form a second oxide layer and a control gate layer is formed over the second oxide layer. An in-process semiconductor device is also described.