1978

Smith, O.D., U.S. Patent 4,085,059, April 18, 1978
Foam Type Coating Remover
[Verification that liquid phase and foam phase cleaning perform identically]

1979

Griesshammer, R., U.S. Patent 4,156,619, May 29, 1979
Process for Cleaning Semiconductor Discs

1988

Ogaya, K., Japanese Patent Abstract 63-239820(A2), October 5, 1988
Washing Method for Semiconductor Device

Leenaars, A.F.M., U.S. Patent 4,781,764, November 1, 1988
Method of Removing Undesired Particles from a Surface of a Substrate
(Experimental proof that bubbles can create a net zero surface tension particulate removal medium)

1989

Liu, B.Y.H., U.S. Patent 4,817,652, April 4, 1989
System for Surface and Fluid Cleaning

1990

McConnell, C.F., U.S. Patent 4,911,761, March 27, 1990
Process and Apparatus for Drying Surfaces

1991

Washitani, A., Japanese Patent 3-30329(A), February 8, 1991
Semiconductor Wafer Cleaning Apparatus

Chung, B.C., U.S. Patent 5,000,795, March 19, 1991
Semiconductor Wafer Cleaning Method and Apparatus

Washitani, A., Japanese Patent 3-94428(A), April 19, 1991
Cleaning of Semiconductor Wafer

1992

Sylla, K.F., U.S. Patent 5,113,597, May 19, 1992
Process for Drying of Plant or Animal Material

Yoshigami, J., Japanese Patent 4-171724(A), June 18, 1992
Method and Apparatus for Washing Semiconductor Substrate

Winebarger, P.M., U.S. Patent 5,175,124, December 29, 1992
Process for Fabricating a Semiconductor Device Using Re-Ionized Water

1993

Leenaars, A.F.M., U.S. Patent 5,271,774, December 21, 1993
Method for Removing in a Centrifuge a Liquid from a Surface of a Substrate

1994

Pustilnik, C.S., U.S. Patent 5,288,332, February 22, 1994
A Process for Removing Corrosive By-Products froma Circuit Assembly

Chung, B.C., U.S. Patent 5,336,371, August 9, 1994
Semiconductor Wafer Cleaning and Rinsing Techniques Using Re-Ionized Water and Tank Overflow

1996

Mohindra, R., U.S. Patent 5,571,337, November 5, 1996
Method for Cleaning and Drying a Semiconductor Wafer

1999

Advocate, G.G., U.S. Patent 5,904,156, May 18, 1999
Dry Film Resist Removal in the Presence of Electroplated C4'S

Beery, H., et al, "Post Etch Removal: Novel Dry Clean Technology Using Densified Fluid Cleaning"
Paper Presented at IITC, Burlingame, CA, June, 1999.

Akatsu, H., U.S. Patent 5,932,493, August 3, 1999
Method to Minimize Watermarks on Silicon Substrates

2000

Kittle, P.A., U.S. Patent 6,090,217, July 18, 2000
Surface Treatment of Semiconductor Substrates

2001

Kittle, P.A., Taiwan 131,360, April 11, 2001
Surface Treatment of Semiconductor Substrates

Bergman, E.J., U.S. Patent 6,286,231, September 11, 2001
Method and Apparatus for High Pressure Wafer Processing and Drying

Kittle, P.A., U.S. Patent 6,296,715, October 2, 2001
Surface Treatment of Semiconductor Substrates

Kittle, P.A., "Semiconductor Wafer Cleaning and Drying Using a Foam Medium"
        Sematech Novel Wafer Cleans Working Group Meeting
        Internet Presentation, November 13, 2001

Hirasaki, G.J., et al, U.S. 2002 0094684, filed November 27, 2001
"Foam Cleaning Process in Semiconductor Manufacturing"
[USPTO rejected, application abandoned]

2002

Bergman, E.J., U.S. Patent 6,.357,142, March 19, 2002
Method and Apparatus for High Pressure Wafer Processing and Drying

Kittle, P.A., U.S. Patent 6,439,247, August 27, 2002
Surface Treatment of Semiconductor Substrates

Kittle, P.A., "Foam Wafer Cleaning - Experimental Proof of Concept"
A technical report showing support of cleaning wafers with foam.

    Kittle, P.A., "Particulate Removal Using a Foam Medium"
Background summary of surface tension gradient (foam) drying and cleaning of semiconductor wafers
Abridged version, "Removing Particles with a Foam Medium," A2C2, page 11-15, January, 2002

Patel, B.P., et al, U.S. 2003 0171239, filed January 28, 2002
"Methods and Compositions for Chemically Treating a Substrate Using Foam Technology"

    Lester, M.A., "Is Foam Wafer Cleaning and Drying the Future?"
        Semiconductor International, 25, #2 (February), 42 (2002).

Kittle, P.A., "Photoresist Residue Removal Using Aqueous Foam" (as submitted, better, clearer SEMs)
  A2C2, pages 13-17, May, 2002 (as published).

2003

Lester, M.A., "A Glimpse into Megasonic Cleaning"
Semiconductor International, 26, #1 (January), 38 (2003).
Describes a possible link between megasonic performance and added bubbles (foam?)

2004

Kittle, P.A., "Aqueous Foam Drying and Cleaning of Semiconductor Wafers"
This is a PowerPoint presentation with about 100 slides and many SEM photographs.  The
presentation covers the major background technology plus the recent experimental work.
This is a large file with a very long download time via modem.
The best viewing technique is to right click on the link followed by saving the file to your computer.
Updated with references, April, 2004

Kittle, P.A., U.S. Patent 6,797,071, September 28, 2004
Surface Treatment of Semiconductor Substrates

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