Exclusion guard and gas-based substrate protection for chemical vapor deposition apparatus

US5843233A · kind A · utility

Assignee

• Novellus Systems, Inc. · US

Inventors

• Everhardus P. van de Ven · Saratoga, US
• Eliot K. Broadbent · Beaverton, US
• Jeffrey C. Benzing · Saratoga, US
• Barry Chin · Sunnyvale, US
• Christopher W. Burkhart · Los Gatos, US
• Lawrence C. Lane · San Jose, US
• Edward J. McInerney · San Jose, US

Key dates

• Filing date: Jun 7, 1995
• Grant date: Dec 1, 1998
• Expiry date: Jun 7, 2015

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/68785
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A platen supports a wafer during the deposition of tungsten, metal nitrides, other metals, and silicides in a chemical vapor deposition reactor. A deposition control gas that includes a suitable inert gas such as argon or a mixture of inert and reactant gases such as argon and hydrogen is introduced through a restrictive opening into an ambient in the reactor. An exclusion guard aligned with the platen has an extension extending over a frontside peripheral region of the wafer. Deposition control gas is introduced under the exclusion guard extension and exits through a restrictive opening between the exclusion guard extension and a wafer frontside peripheral region. The restrictive opening provides a uniform pressure of deposition control gas at the edge and frontside of the wafer to prevent deposition on the wafer edge and backside.