Plasma process uniformity across a wafer by controlling a variable frequency coupled to a harmonic resonator

US8080479B2 · kind B2 · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• Kenneth S. Collins · San Jose, US
• Hiroji Hanawa · Sunnyvale, US
• Kartik Ramaswamy · San Jose, US
• Douglas A. Buchberger, Jr. · Livermore, US
• Shahid Rauf · Pleasanton, US
• Kallol Bera · San Jose, US
• Lawrence Wong · Fremont, US
• Walter R. Merry · Cupertino, US
• Matthew L. Miller · Houston, US
• Steven C. Shannon · San Mateo, US
• Andrew Nguyen · San Jose, US
• James P. Cruse · Santa Cruz, US
• James D. Carducci · Sunnyvale, US
• Troy S. Detrick · Los Altos, US
• Subhash Deshmukh · Livermore, US
• Jennifer Y. Sun · Mountain View, US

Key dates

• Filing date: Apr 11, 2007
• Grant date: Dec 20, 2011
• Expiry date: Mar 8, 2030

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/6831
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

A method of processing a workpiece in a plasma reactor chamber includes coupling RF power via an electrode to plasma in the chamber, the RF power being of a variable frequency in a frequency range that includes a fundamental frequency f. The method also includes coupling the electrode to a resonator having a resonant VHF frequency F which is a harmonic of the fundamental frequency f, so as to produce VHF power at the harmonic. The method controls the ratio of power near the fundamental f to power at harmonic F, by controlling the proportion of power from the generator that is up-converted from f to F, so as to control plasma ion density distribution.