Clamping ring and susceptor therefor

US5326725A · kind A · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• Semyon Sherstinsky · San Francisco, US
• Charles C. Harris · High Point, US
• Mei Chang · San Jose, US
• Dale R. Du Bois · Los Gatos, US
• James Roberts · Campbell, US
• Susan Telford · Cupertino, US
• Ronald L. Rose · San Jose, US
• Meng Chu Tseng · Saratoga, US
• Karl A. Littau · Palo Alto, US

Key dates

• Filing date: Mar 11, 1993
• Grant date: Jul 5, 1994
• Expiry date: Mar 11, 2013

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/68735
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A clamping ring having a downwardly extending finger that mates with a pocket in the periphery of a susceptor for supporting a wafer in a chemical vapor deposition chamber, provides alignment of the clamping ring, the wafer and the susceptor. A source of inert gas connected to the pocket provides a positive pressure in the pocket that prevents reactive gas in the chamber from reaching the edge and backside of the wafer. A source of vacuum connected to the susceptor support surface ensures good contact between the wafer and the susceptor. The clamping ring also has a lip extending over the top surface of the wafer having a rear surface that has a negative angle with respect to the upper surface of the clamping ring, providing a knife edge seal to the wafer, reducing the area of contact between the clamping ring and the wafer and providing a reduced area of thermal contact between the clamping ring and the wafer.