Apparatus for testing integrated circuits

• US 5,148,103 A
• Filed: 10/31/1990
• Issued: 09/15/1992
• Est. Priority Date: 10/31/1990
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Pasiecznik, John Jr.
• Primary Examiner(s): NGUYEN, VINH P
• Application Number:
  US07/606,676
• Time in Patent Office: 685 Days
• Field of Search: 324/72 S, 324/158 F, 324/158 P, 439/482, 439/86, 439/66, 439/67, 361/397, 361/401
• US Class Current: 324/754.08
• CPC Class Codes: G01R 1/0735 arranged on a flexible frame or film

Abstract

A membrane probe (10, 12, 14, 16, 58, 144) for testing integrated circuits (56,138) while still on the wafer upon which they are manufactured includes a flexible visually clear and self planarizing membrane (26) having circuit traces (20) and ground shielding planes (14), terminating resistor (152) and active buffer chips (172) formed thereon. Probe contact pads (36,38) electroplated on areas of the traces, and connector pads (32) plated on the membrane facilitate rapid detachable connection to a test fixture (50). The probe has a configuration, dimension and structure like that of the wafer itself so that automated pick and place equipment (136, 142) employed for handling the wafers (138) may also be used to handle the probes (144). An unique test fixture (50) is adapted to receive and detachably secure a selected probe to the fixture. A metal-on-elastomer annulus (88,104) is employed in the test fixture to make electrical contact between contact pads (32) plated on the back side of the membrane probe and a printed circuit board that is used to route signals to the testing equipment.

Claims

1. Apparatus for testing integrated circuit chips comprising:

a fixture mounting member having test circuitry connections,

an elastomeric member carried by said mounting member and having a plurality of connector elements thereon,

said elements being electrically connected to said test circuitry connections, and

a probe comprising;

a flexible membrane,

a plurality of contact pads on said membrane,

a plurality of electrical conductors on said membrane electrically connected to said contact pads, said conductors and contact pads being positioned on one side of said membrane,

a substrate having a first side supporting said membrane and having a second side,

means for connecting said membrane to said fixture mounting member,

a plurality of membrane connector pads formed on said second side of said substrate and connected to said conductors,

said probe being positioned in said fixture mounting member with said membrane connector pads in contact with said connector elements of said elastomeric member.

2. The apparatus of claim 1 including a plurality of vias extending through said substrate and electrically interconnecting said conductors and said membrane pads.

3. The apparatus of claim 1 wherein said membrane connector pads are positioned around the periphery of said second side of said substrate and wherein said second side has a smooth, flat annular surface configured and arranged to be forcibly attracted by a vacuum applied by a test fixture.

4. The apparatus of claim 1 wherein said means for connecting said membrane comprises means for applying a vacuum to said membrane to pull said membrane toward said elastomeric member.

5. The apparatus of claim 4 including a gas chamber fixed to said mounting member and sealed to said membrane, and means for introducing pressurized gas into said chamber.

6. The apparatus of claim 1 wherein said connector elements of said elastomeric member are resiliently supported by said elastomeric member for deflection individually relative to one another.

7. The apparatus of claim 1 wherein said fixture mounting member is in annular member having an annular inner peripheral portion, said elastomeric member comprising a resilient annular member fixed to said peripheral inner portion of said fixture mounting member, said substrate comprising an annular body having an open inner area, and said flexible membrane fixed to and extending across said open inner area.

8. Apparatus for testing integrated circuit chips comprising:

a fixture mounting member having test circuitry connections,

an elastomeric member connected to said mounting member and having a plurality of connector elements thereon,

said elements being electrically connected to said test circuitry connections,

a probe including;

a probe body having first and second sides,

probe contact elements on said first probe side,

probe connector pads on said second probe side, and electrically connected to said probe contact elements, and

cooperating means on said fixture mounting member and probe for detachably mechanically interconnecting said probe to said fixture mounting member in a probe operational position, said probe connector pads in said operational position of said probe being in firm electrical contact with said connector elements of said elastomeric member.

9. The apparatus of claim 8 wherein said cooperating means comprises means for urging said probe toward and against said elastomeric member.

10. The apparatus of claim 8 wherein said cooperating means for detachably mechanically interconnecting said probe comprises means for applying a vacuum to said probe to pull said probe toward said elastomeric member.

11. The apparatus of claim 8 including a gas chamber fixed to said mounting member and sealed to said probe, and means for introducing pressurized gas into said chamber, said probe including a flexible membrane on which are mounted said probe contact elements.

12. The apparatus of claim 8 wherein said elastomeric member comprises an elastomeric annulus having a plurality of circumferentially spaced electrically conductive conductor elements fixed thereto, said probe connector pads extending around the circumference of said second probe side in mutually spaced relation and electrically contacting said conductor elements.

13. The apparatus of claim 8 wherein said fixture mounting member comprises a multi-level printed circuit board having a plurality of electrical conductors and said elastomeric member is secured thereto with said connector elements of said elastomeric member extending between said probe connector pads and said electrical conductors of said printed circuit board.

14. The apparatus of claim 8 wherein said fixture mounting member comprises a multi-level printed circuit board comprising a substantially rigid inner board layer, a dielectric outer substrate layer, and an intermediate dielectric layer interposed between said dielectric outer layer and said inner layer, said intermediate dielectric layer being recessed radially outwardly of said inner and outer layers to define an annular recess, said elastomeric member comprising an elastomeric annulus positioned in said annular recess having a plurality of connecting conductors on said outer layer between said intermediate layer and said outer layer, said elastomeric member connector elements being positioned to interconnect connecting conductors of said outer layer and connector pads of said probe.

15. Apparatus for testing integrated circuit chips comprising:

a fixture mounting plate having test circuitry connections,

a gas chamber housing mounted to said fixture mounting plate,

an annular circuit board carried by said fixture mounting plate and having an internal aperture receiving a portion of said gas chamber housing, said circuit board having a plurality of electrical conductors,

an annular elastomeric member carried by said circuit board and having elastomeric member connector elements connected to said circuit board electrical conductors,

a probe including;

a flexible probe body having first and second sides,

probe contact elements on said first probe side, and

probe connector pads on said second probe side electrically connected to said probe contact elements, said probe connector pads being in contact with and pressing against said elastomeric member connector elements,

vacuum means extending into said gas chamber housing having a vacuum aperture adjacent said probe body for attaching said probe body to said mounting plate and circuit board with said probe connector pads in contact with and pressed against said elastomeric member connector elements,

said gas chamber housing having an opening in contact with said second probe side, and

means for introducing gas under pressure into said gas chamber housing to press said probe body away from said gas chamber housing.