Selective nitride: oxide anisotropic etch process

US6656375B1 · kind B1 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Michael D. Armacost · Winooski, US
• David M. Dobuzinsky · New Windsor, US
• John C. Malinowski · Jericho, US
• Hung Y. Ng · New Milford, US
• Richard S. Wise · Beacon, US
• Chienfan Yu · Highland Mills, US

Key dates

• Filing date: Jan 28, 1998
• Grant date: Dec 2, 2003
• Expiry date: Nov 8, 2019

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/31116
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

An anisotropic etching process for a nitride layer of a substrate, the process comprising using an etchant gas which comprises a hydrogen-rich fluorohydrocarbon, an oxidant and a carbon source. The hydrogen-rich fluorohydrocarbon is preferably one of CH3F or CH2F2, the carbon source is preferably one of CO2 or CO, and the oxidant is preferably O2. The fluorohydrocarbon is preferably present in the gas at approximately 7%-35% by volume, the oxidant is preferably present in the gas at approximately 1%-35% by volume, and the carbon source is preferably present in the gas at approximately 30%-92%.