Stephen B Swan

US Patent:

8481142, Jul 9, 2013

Filed:

Aug 30, 2005

Appl. No.:

11/215845

Inventors:

Thanas Budri - Portland ME, US
Thomas Francis - South Portland ME, US
David Tucker - Falmouth ME, US
Stephen W. Swan - Windham ME, US
Sergei Drizlikh - Scarborough ME, US

Assignee:

National Semiconductor Corporation - Santa Clara CA

International Classification:

H01L 21/302

US Classification:

428 72, 216 59, 428710

Abstract:

A system and method for monitoring chloride content and concentration induced by a metal etch process is disclosed. A blank metal film is deposited on a semiconductor wafer. A metal etch process is then applied to partially etch the blank metal film on the wafer. The metal etch process exposes the metal film to chlorine. The wafer is then scanned using surface profiling total X-ray reflection fluorescence. A chlorine concentration map is generated that shows quantitative and spatial information about the chlorine on the wafer. Information from the chlorine concentration map is then used to select a value of chlorine concentration for a metal etch process that will not create metal chloride corrosion on a semiconductor wafer.