Patents by Inventor Douglas G. Mitchell

Douglas G. Mitchell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6361675
    Abstract: A method of manufacturing a semiconductor component includes depositing a first electrically conductive layer (675) over a substrate (270), forming a patterned plating mask (673) over the first electrically conductive layer, coupling a first plating electrode (250) to the first electrically conductive layer without puncturing the plating mask, and plating a second electrically conductive layer onto portions of the first electrically conductive layer. A plating tool for the manufacturing method includes an inner weir (220) located within an outer weir (210), an elastic member (230) over a rim (211) of the outer weir, a pressure ring (240) located over the rim of the outer weir and the elastic member, and a plurality of cathode contacts (250, 251, 252, 253) located between the pressure ring and the outer weir. The substrate is positioned between the elastic member and the pressure ring.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: March 26, 2002
    Assignee: Motorola, Inc.
    Inventors: Timothy Lee Johnson, Joseph English, David Austin, George F. Carney, Kandis Mae Knoblauch, Douglas G. Mitchell
  • Publication number: 20010008224
    Abstract: A method of manufacturing electronic components includes disposing a top metal layer (502) comprised of solder over a bottom metal layer (201, 202) comprised of titanium or tungsten, and selectively etching the bottom metal layer (201, 202) over the top metal layer (502) with an etchant mixture (601) comprised of an etchant, an additive to control the temperature of the etchant mixture (601), and another additive to reduce the redeposition of the top layer (502).
    Type: Application
    Filed: July 30, 1998
    Publication date: July 19, 2001
    Inventors: ERIC J. WOOLSEY, DOUGLAS G. MITCHELL, GEORGE F. CARNEY, FRANCIS J. CARNEY, CARY B. POWELL
  • Patent number: 5773359
    Abstract: An interconnect system (31) includes an interconnect bump (29) over an under bump metallurgy (25). The under bump metallurgy (25) includes a barrier layer (26) having a barrier material such as titanium, an adhesion layer (28) having an adhesion material such as copper, and a mixture layer (27) having both the barrier material and the adhesion material. The mixture layer (27) is located between the barrier layer (26) and the adhesion layer (28), and the adhesion layer (28) is located between the mixture layer (27) and the interconnect bump (29). The interconnect bump (29) contains solder and is used as an etch mask when patterning the under bump metallurgy (25).
    Type: Grant
    Filed: December 26, 1995
    Date of Patent: June 30, 1998
    Assignee: Motorola, Inc.
    Inventors: Douglas G. Mitchell, Francis J. Carney, Eric J. Woolsey
  • Patent number: 5480835
    Abstract: A method for forming an electrical interconnect on a substrate. At least one pad (14) is formed on a substrate (11). The pad (14) is formed having a non-wetting surface (12) and a wettable surface (13). Photoresist (44) is patterned on a substrate (41) forming a cavity on a pad (46) leaving a non-wetting surface (42) and a wettable surface (43) exposed. Interconnect material (56) is formed on a non-wetting surface (52) and a wettable surface (53) of pad 57. Interconnect material (56) is reflowed forming an interconnect ball (74) on a wettable surface (73). Surface tension causes interconnect material (56) when reflowed to flow from a non-wetting surface (72) to the wettable surface (73) and ball up to form the interconnect ball (74).
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: January 2, 1996
    Assignee: Motorola, Inc.
    Inventors: Francis J. Carney, George F. Carney, Douglas G. Mitchell
  • Patent number: 4927505
    Abstract: A titanium-tungsten-nitride/titanium-tungsten/gold (TiWN/TiW/Au) packaging interconnect metallization scheme is used to provide electrical contact to chip level interconnect metallization on a semiconductor substrate. The TiWN/TiW/Au packaging interconnect metallization scheme provides for good adhesion and barrier properties that withstand high temperatures and improve the reliability of the semiconductor chip. The TiWN layer provides good adhesion to the chip level interconnect metallization and the passivation layer. It also provides improved barrier properties to prevent the diffusion of other metal atoms through it. The TiW layer provides good adhesion to the gold metal layer. A gold bump may be electroplated to the gold layer and automatically bonded to a conductive lead of a tape in TAB packaging; or a wire bonded to the gold layer in conventional packaging.
    Type: Grant
    Filed: July 28, 1989
    Date of Patent: May 22, 1990
    Assignee: Motorola Inc.
    Inventors: Ravinder K. Sharma, Harry J. Geyer, Douglas G. Mitchell
  • Patent number: 4880708
    Abstract: A titanium-tungsten-nitride/titanium-tungsten/gold (TiWN/TiW/Au) packaging interconnect metallization scheme is used to provide electrical contact to chip level interconnect metallization on a semiconductor substrate. The TiWN/TiW/Au packaging interconnect metallization scheme provides for good adhesion and barrier properties that withstand high temperatures and improve the reliability of the semiconductor chip. The TiWN layer provides good adhesion to the chip level interconnect metallization and the passivation layer. It also provides improved barrier properties to prevent the diffusion of other metal atoms through it. The TiW layer provides good adhesion to the gold metal layer. A gold bump may be electroplated to the gold layer and automatically bonded to a conductive lead of a tape in TAB packaging; or a wire bonded to the gold layer in conventional packaging.
    Type: Grant
    Filed: July 5, 1988
    Date of Patent: November 14, 1989
    Assignee: Motorola, Inc.
    Inventors: Ravinder K. Sharma, Harry J. Geyer, Douglas G. Mitchell
  • Patent number: D328588
    Type: Grant
    Filed: October 19, 1990
    Date of Patent: August 11, 1992
    Inventor: Douglas G. Mitchell