[54] CONNECTING TEST EQUIPMENT TO
ADJACENT LEGS OF AN IC OR THE LIKE
BY INTERDIGITATING CONDUCTIVE
WEDGES WITH THE LEGS
[75] Inventor: Robert H. WardweD, Colorado
Springs, Colo.
[73] Assignee: Hewlett-Packard Company, Palo Alto, Calif.
[ * ] Notice: The term of this patent shall not extend beyond the expiration date of Pat. No. 5,463,324.
[21] Appl. No.: 143,005
[22] Filed: Oct 26,1993
[51] Int CL6 G01R 1/073
[52] U.S. CI 324/762; 324/754
[58] Field of Search 324/754,755,
324/762, 760; 439/65, 68, 70, 59, 912
[56] References Cited
U.S. PATENT DOCUMENTS
4,682,838 7/1987 Achting et al 439/696
4,833,404 5/1989 Meyer et al 439/54
4,835,469 5/1989 Jones et al 324/754
5,049,813 9/1991 Van Loan et al 439/70
5,156,649 10/1992 Compton et al 324/762
5,166,609 11/1992 Cole et al 439/68
5,345364 9/1994 Biernath 439/59
5,391,082 2/1995 Airhart 324/762
5,463,324 10/1995 Wardwdl et al 324/754
Attorney, Agent, or Firm—Edward L Miller
[57] ABSTRACT
A probe for making electrical connections to the legs of an already mounted integrated circuit carries rows of tapered wedges. The wedges within a row are spaced apart by an amount that corresponds to the width of the IC's legs. For n-many legs on a side of the IC there are n+1 corresponding wedges, which then have n-many intervening spaces. As the positioned probe is pressed down the spaces between the wedges receive the legs of the IC. and wedges become wedged between the IC's legs. Each wedge has left and right conductive surfaces separated by an insulator. Each leg of the IC has a wedge to its left and a wedge to its right. Within the probe the right-hand conductive surface of the wedge to the left of a leg, and the left-hand conductive surface of the wedge to the right of that leg, are electrically connected together. Thus, the probe makes electrical contact to each leg in two places. The tapered wedges are of Ni- and Au-plated BeCu separated by acrylic adhesive and Kapton. Acrylic adhesive and Kapton are also used as the spacer between wedges. The rows of wedges are cemented to a mantle. A lead frame soldered to the butt end of the wedges connects opposing surfaces of adjacent wedges and makes the interconnection between the rows of wedges and an array of pins in a pin block at the top of the probe. Sticks of coplanar wedges are made by laminating layers of material in a press. The taper of the wedge tip arises from layers of shorter length in conjunction with a shaped surface in the laminating press. N+1 sticks are laminated together with intervening spacers to form a stack from which rows of n+1 wedges may be removed.
