Wafer centering in pocket to improve azimuthal thickness uniformity at wafer edge

US9698042B1 · kind B1 · utility

Assignee

• Lam Research Corporation · US

Inventors

• Chloe Baldasseroni · Tigard, US
• Ted Minshall · Sherwood, US
• Frank L. Pasquale · Beaverton, US
• Shankar Swaminathan · Hillsboro, US
• Ramesh Chandrasekharan · Portland, US

Key dates

• Filing date: Jul 22, 2016
• Grant date: Jul 4, 2017
• Expiry date: Jul 22, 2036

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/68771
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method for reducing slippage of a wafer during film deposition includes pumping out a processing chamber while the wafer is supported on lift pins or a carrier ring and lowering the wafer onto support members configured to minimize wafer slippage during deposition of the film. A multi-station processing chamber, such as a processing chamber for atomic layer deposition, can include a chuck-less pedestal at each station having wafer supports configured to prevent the wafer from moving off center by more than 400 microns. To minimize a gas cushion beneath the wafer, the wafer supports can provide a gap of at least 2 mils between the back side of the wafer and the wafer-facing surface of the pedestal.