Contact structure and production method thereof

• US 6,250,933 B1
• Filed: 01/20/2000
• Issued: 06/26/2001
• Est. Priority Date: 01/20/2000
• Status: Expired due to Fees

• Current Assignee: Advantest Corporation
• Original Assignee: Advantest Corporation
• Inventors: Khoury, Theodore A., Frame, James W.
• Primary Examiner(s): Sircus, Brian
• Assistant Examiner(s): Zarroli, Michael C.
• Application Number:
  US09/488,661
• Time in Patent Office: 523 Days
• Field of Search: 439/66, 439/81, 324/754, 324/757, 324/762
• US Class Current: 439/66
• CPC Class Codes: G01R 1/06738 related to tip portion
• CPC Class Codes: G01R 1/07314 the body of the probe being perpendicular to test object, e.g. bed of nails or probe with bump contacts on a rigid support on an elastic support, e.g. a film, G01R1/0735
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01R 12/714 with contacts abutting directly the printed circuit; Button contacts therefore provided on the printed circuit
• CPC Class Codes: H01R 13/24 resilient; resiliently-mounted
• CPC Class Codes: H05K 3/4092 Integral conductive tabs, i.e. conductive parts partly detached from the substrate

Abstract

A contact structure for achieving an electrical connection with a contact target is formed of a contact substrate and a plurality of contactors mounted on the contact substrate. The contactors are produced on a semiconductor substrate or other dielectric by a microfabrication technology. Each of the contactors has a contact bump to contact with the contact target. In one aspect, one of the base portions of the contactor is slidably formed on the surface of the contact substrate. A spring force is generated when the contactor is pressed against the contact target. Various types of contact structures and the associated production methods are also described.

Claims

1. A contact structure for establishing an electrical connection with a contact target, comprising:

a contact substrate;

a plurality of contactors mounted on the contact substrate, each of the contactors having a bridge like shape formed with a horizontal portion and two angled portions for supporting the horizontal portion, and two base portions at respective ends of the angled portions attached to the contact substrate, at least one of the two base portions being electrically connected to a contact pad provided on the contact substrate;

a contact bump attached to the horizontal portion of each of the contactors;

wherein one of the angled portions is widened toward the bottom thereof and is connected to two base portions, and wherein the horizontal portion and the angled portions of the contactor produce a contact force when the contact structure is pressed against the contact target.

2. A contact structure as defined in claim 1, wherein the contactor has an asymmetrical shape in cross section wherein the two angled portions have different angle and length from each other to promote a movement of the contact bump in a direction perpendicular to a direction of pressure applied between the contact structure and the contact target.

3. A contact structure as defined in claim 1, wherein the contactor has a symmetrical shape in cross section wherein the two angled portions have the same length and angle with one another.

4. A contact structure as defined in claim 1, wherein both of the angled portions are widened toward the bottom thereof, each of which is connected to two base portions.

5. A contact structure as defined in claim 1, wherein said contactor is made of nickel, aluminum, copper, nickel palladium, rhodium, nickel gold, or iridium.

6. A contact structure as defined in claim 1, wherein said horizontal portion of each of the contactors is provided with two or more contact bumps made of hard metal.

7. A contact structure as defined in claim 1, wherein said contact bump has a spherical shape and is made of a glass ball coated with tungsten or other metal.

8. A contact structure as defined in claim 1, wherein said contact bump has a spherical, squarish, trapezoidal, pyramidal or conical shape.

9. A contact structure as defined in claim 1, wherein said contact bump is made of hard metal including nickel, beryllium, aluminum, copper, nickel-cobalt-iron alloy or iron nickel alloy.

10. A contact structure as defined in claim 1, wherein said contact bump is formed of base metal such as nickel, beryllium, aluminum, copper, nickel-cobalt-iron alloy or iron nickel alloy and plated with a highly conductive, non-oxidizing metal such as gold, silver, nickel palladium, rhodium, nickel gold, or iridium.

11. A contact structure as defined in claim 1, wherein said contact bump is attached to the contactor by soldering, brazing, welding, or applying a conductive adhesive.

13. A contact structure as defined in claim 1, wherein said contact bump has a spherical, squarish, trapezoidal, pyramidal or conical shape.

12. A contact structure for establishing an electrical connection with a contact target, comprising:

a contact substrate;

a plurality of contactors mounted on the contact substrate, each of the contactor having a bridge like shape formed with a horizontal portion, two angled portions for supporting the horizontal portion and two base portions at respective ends of the angled portions, one of the two base portions being attached to the contact substrate and electrically connected to a contact pad provided on the contact substrate, and the other base portion being slidably provided on the surface of the contact substrate;

a contact bump attached to the horizontal portion of each of the contactors;

wherein the horizontal portion and the angled portions of the contactor produce a contact force and said other base portion slides on the surface of said contact base when the contactor is pressed against the contact target, whereby promoting scrubbing of a surface of said contact target by said contact bump.

14. A contact structure as defined in claim 12, wherein said contact bump is made of hard metal including nickel, beryllium, aluminum, copper, nickel-cobalt-iron alloy or iron nickel alloy.

15. A contact structure as defined in claim 12, wherein said contact bump is formed of base metal such as nickel, beryllium, aluminum, copper, nickel-cobalt-iron alloy or iron nickel alloy and plated with a highly conductive, non-oxidizing metal such as gold, silver, nickel palladium, rhodium, nickel gold, or iridium.

16. A contact structure for establishing an electrical connection with a contact target, comprising:

a dielectric substrate having a depression on a surface thereof; and

a contactor having a bridge like shape formed on the substrate through a microfabrication process, the contactor being formed with a horizontal portion having two angled ends connected to the dielectric substrate where the horizontal portion is positioned over the depression on the dielectric substrate;

wherein said contactor is formed of a horizontal portion having a free end and the other end thereof is connected to an angled portion, said angled portion having a base portion which is connected to the dielectric substrate in such a way that said free end of said horizontal portion is positioned over said depression on said dielectric substrate, and wherein the horizontal portion of the contactor produces a contact force when the contactor is pressed against the contact target such that the horizonal portion enters the depression while exerting the contact force.

17. A contact structure as defined in claim 16, wherein two contactors each having the horizontal portion with the free end are provided to the dielectric substrate in such a way that said free ends of said two horizontal portions are positioned over said depression on said dielectric substrate.