Patents by Inventor Lloyd W. Darnell

Lloyd W. Darnell 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).

  • Tool and fixture for the removal of tab leads bonded to semiconductor die pads
    Patent number: 5649981
    Abstract: An apparatus for use in a removable tab procedure whereby tabs (7) are affixed to the pads (3) by initially having the bonding surface as flat as possible so that bonding pressures from pad to pad are relatively uniform. Bonding is preformed with the pressure applied to the pads being such that the tabs can later be easily removed without damage to the die pads, yet sufficiently strong so that the tabs do not come loose during burn in and testing. A bond strength pull between about 5 and about 40 grams per pad is appropriate for this purpose. The tabs are removed by placing the tested die (1) and attached tabs in a fixture (11) and providing a tool (31) dimensioned and moved along a path (13, 15, 17, 19) whereby each of the tabs is serially removed with the pressure applied to each tab to provide removal being preferably no greater than 40 grams.
    Type: Grant
    Filed: September 23, 1996
    Date of Patent: July 22, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Richard W. Arnold, Lloyd W. Darnell
  • Process of removing a tape automated bonded semiconductor from bonded leads
    Patent number: 5591649
    Abstract: A removable tab process whereby tabs (7) are affixed to the pads (3) by initially having the bonding surface as flat as possible so that bonding pressures from pad to pad are relatively uniform. Bonding is performed with the pressure applied to the pads being such that the tabs can later be easily removed without damage to the die pads, yet sufficiently strong so that the tabs do not come loose during burn in and testing. A bond strength pull between about 5 and about 40 grams per pad is appropriate for this purpose. The tabs are removed by placing the tested die (1) and attached tabs in a fixture (11) and providing a tool (31) dimensioned and moved along a path (13, 15, 17, 19) whereby each of the tabs is serially removed with the pressure applied to each tab to provide removal being preferably no greater than 40 grams.
    Type: Grant
    Filed: January 19, 1995
    Date of Patent: January 7, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Richard W. Arnold, Lloyd W. Darnell