Variable width resilient conductive contact structures

• US 7,435,108 B1
• Filed: 07/30/1999
• Issued: 10/14/2008
• Est. Priority Date: 07/30/1999
• Status: Expired due to Fees

• Current Assignee: FormFactor Incorporated
• Original Assignee: FormFactor Incorporated
• Inventors: Eldridge, Benjamin N., Mathieu, Gaetan
• Primary Examiner(s): Prasad; Chandrika
• Application Number:
  US09/364,788
• Time in Patent Office: 3,364 Days
• Field of Search: 439/71, 439/66, 439/81, 439/91, 439/482, 439/591, 361/772, 361/774, 361/776, 257/659, 438/618
• US Class Current: 439/81
• CPC Class Codes: G01R 1/06727 Cantilever beams
• CPC Class Codes: G01R 1/07342 the body of the probe being at an angle other than perpendicular to test object, e.g. probe card
• CPC Class Codes: H01L 2224/02311 Additive methods
• CPC Class Codes: H01L 2224/02313 Subtractive methods
• CPC Class Codes: H01L 2224/02335 Free-standing redistribution layers
• CPC Class Codes: H01L 2224/0235 Shape of the redistribution layers
• CPC Class Codes: H01L 2224/0239 Material of the redistribution layers
• CPC Class Codes: H01L 2224/0345 Physical vapour deposition [PVD], e.g. evaporation, or sputtering
• CPC Class Codes: H01L 2224/03472 Profile of the lift-off mask
• CPC Class Codes: H01L 2224/0361 Physical or chemical etching
• CPC Class Codes: H01L 2224/03912 the bump being used as a mask for patterning the bonding area
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/05008 Bonding area integrally formed with a redistribution layer on the semiconductor or solid-state body, e.g.
• CPC Class Codes: H01L 2224/0502 Disposition
• CPC Class Codes: H01L 2224/05027 the internal layer extending out of an opening
• CPC Class Codes: H01L 2224/05552 in top view
• CPC Class Codes: H01L 2224/05563 Only on parts of the surface of the internal layer
• CPC Class Codes: H01L 2224/056 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/10122 being formed on the semiconductor or solid-state body to be connected
• CPC Class Codes: H01L 2224/1145 Physical vapour deposition [PVD], e.g. evaporation, or sputtering
• CPC Class Codes: H01L 2224/11452 : Chemical vapour deposition [CVD], e.g. laser CVD
• CPC Class Codes: H01L 2224/11462 : Electroplating
• CPC Class Codes: H01L 2224/11464 : Electroless plating
• CPC Class Codes: H01L 2224/11472 : Profile of the lift-off mask
• CPC Class Codes: H01L 2224/13012 : in top view
• CPC Class Codes: H01L 2224/13016 : in side view
• CPC Class Codes: H01L 2224/13023 : the whole bump connector protruding from the surface
• CPC Class Codes: H01L 2224/13026 : relative to the bonding area, e.g. bond pad, of the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/13082 : Two-layer arrangements
• CPC Class Codes: H01L 2224/131 : with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/13144 : Gold [Au] as principal constituent
• CPC Class Codes: H01L 2224/13155 : Nickel [Ni] as principal constituent
• CPC Class Codes: H01L 2224/13164 : Palladium [Pd] as principal constituent
• CPC Class Codes: H01L 2224/13173 : Rhodium [Rh] as principal constituent
• CPC Class Codes: H01L 2224/1379 : with a principal constituent of the material being a polymer, e.g. polyester, phenolic based polymer, epoxy
• CPC Class Codes: H01L 2224/138 : with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/1412 : Layout
• CPC Class Codes: H01L 2224/1413 : Square or rectangular array
• CPC Class Codes: H01L 2224/16057 : in side view
• CPC Class Codes: H01L 2224/81007 : involving a permanent auxiliary member being left in the finished device, e.g. aids for holding or protecting the bump connector during or after the bonding process
• CPC Class Codes: H01L 2224/81191 : wherein the bump connectors are disposed only on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/81801 : Soldering or alloying
• CPC Class Codes: H01L 2224/8185 : using a polymer adhesive, e.g. an adhesive based on silicone, epoxy, polyimide, polyester
• CPC Class Codes: H01L 2224/819 : with the bump connector not providing any mechanical bonding
• CPC Class Codes: H01L 24/02 : Bonding areas on insulating substrates, e.g. chip carriers, H01L23/49816, H01L23/49838, H01L23/5389; Manufacturing methods related thereto
• CPC Class Codes: H01L 24/03 : Manufacturing methods
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/11 : Manufacturing methods for bumps on insulating substrates H01L21/4853
• CPC Class Codes: H01L 24/13 : of an individual bump connector
• CPC Class Codes: H01L 24/14 : of a plurality of bump connectors
• CPC Class Codes: H01L 24/16 : of an individual bump connector
• CPC Class Codes: H01L 24/72 : Detachable connecting means consisting of mechanical auxiliary parts connecting the device, e.g. pressure contacts using springs or clips
• CPC Class Codes: H01L 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01019 : Potassium [K]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01045 : Rhodium [Rh]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01R 13/03 : characterised by the material, e.g. plating, or coating materials

Abstract

Interconnect assemblies having resilient contact elements and methods for making these assemblies. In one aspect, the interconnect assembly includes a substrate and a resilient electrical contact element disposed on the substrate. A first portion of the resilient contact structure is disposed on the substrate and a second portion extends away from the substrate and is capable of moving from a first position to a second position under the application of a force. A stop structure is disposed on the surface of the substrate and on a surface of the first portion of the resilient contact structure. According to another aspect of the present invention, a beam portion of the resilient contact structure has a substantially triangular shape.

Claims

1. An electronic component comprising:

a substrate including a conductive element disposed at a surface of the substrate; and

a freestanding, resilient, electrically conductive contact structure comprising a base portion attached to the conductive element, a tip portion displaced a vertical distance away from the surface of the substrate, and a beam portion between the base portion and the tip portion, a length of the beam portion extending from where the base portion is attached to the conductive element to where the beam portion meets the tip portion, the beam portion being displaced away from the surface of the substrate along all of the length,

wherein;

a width dimension of the beam portion decreases along all of the length of the beam portion,

all of the length of the beam portion is shaped in a convex curve that is convex with respect to the surface of the substrate, and

the width dimension of the beam portion is parallel to the surface of the substrate where the beam portion and the tip portion meet.

2. The electronic component of claim 1 further comprising:

a connecting layer coupling the conductive element to internal circuitry within the electronic component;

a passivation layer disposed on the surface of the substrate, the passivation layer having an opening at the conductive element; and

at least one electrically conductive layer disposed on the passivation layer and on the conductive element,

wherein the base portion of the contact structure is electrically coupled through the at least one electrically conductive layer to the conductive element.

3. The electronic component of claim 2, wherein the conductive element comprises a terminal.

4. The electronic component of claim 2, wherein the tip portion comprises a pointed end.

5. The electronic component of claim 2, wherein the substrate comprises a semiconductor device.

6. The electronic component of claim 2, wherein the contact structure comprises the plurality of layers.

7. The electronic component of claim 6, wherein ones of the layers comprise metals.

8. The electronic component of claim 2 further comprising a plurality of the contact structures, wherein adjacent contact structures are spaced between 2.5 microns and 2000 microns from each other.

9. The electronic component of claim 2, wherein the tip portion comprises a beveled peripheral edge.

10. The electronic component of claim 2, wherein the beam portion comprises a triangular shape.

11. The electronic component of claim 10, wherein the tip portion comprises a quadrilateral shape.

12. The electronic component of claim 11, wherein the tip portion comprises a rectangular shape.

13. The electronic component of claim 1, wherein the plurality of layers comprise an electrically conductive seed layer and a layer of structural material disposed on the seed layer.

14. The electronic component of claim 1, wherein the beam portion comprises the plurality of layers of materials.

15. The electronic component of claim 1, wherein the vertical distance is perpendicular to the surface of the substrate at which the conductive element is disposed.

16. The electronic component of claim 1, wherein the tip is disposed above the surface of the substrate at which the conductive element is disposed.

17. The electronic component of claim 1 wherein the base portion comprises a plurality of layers, a first of the layers comprising a first material and a second of the layers comprising a second material, the first material being different than the second material.

18. The electronic component of claim 1 further comprising a plurality of conductive contact structures each comprising a base portion attached to a conductive element disposed at the surface of the substrate, a tip portion displaced a vertical distance away from the surface of the substrate, and a beam portion between the base portion and the tip portion, wherein each of the contact structures is free standing and structurally distinct from the others of the contact structures.

19. The electronic component of claim 18 further comprising a stop structure disposed on the surface of the substrate, the stop structure comprising a plurality of openings, tip portions of the plurality of contact structures extending through the openings.

20. The electronic component of claim 19, wherein the stop structure covers substantially an entire portion of the surface of the substrate.

21. The electronic component of claim 18, wherein:

the base portion of each contact structure is generally rectangular,

the tip portion of each contact structure is generally rectangular, and

a spacing between centers of adjacent tip portions is less than a spacing between centers of adjacent base portions.

22. An electronics system comprising:

a first substrate including a conductive element disposed at a surface of the first substrate;

a freestanding, resilient, electrically conductive contact structure comprising a base portion attached to the conductive element of the first substrate, one and only one tip portion displaced a vertical distance away from the surface of the first substrate, and one and only one beam portion between the base portion and the tip portion, wherein a length of the beam portion extends from where the base portion is attached to the conductive element to where the beam portion meets the tip portion, the beam portion being displaced away from the surface of the substrate along all the length of the beam portion, wherein a width of the beam portion decreases along all of the length of the beam portion, all of the length of the beam portion is shaped in a convex curve that is convex with respect to the surface of the substrate, and the width dimension of the beam portion is parallel to the surface of the substrate where the beam portion and the tip portion meet; and

a second substrate including a conductive contact element in physical contact with the one and only one tip portion of the contact structure and deflecting the contact structure, the contact structure exerting a force against the contact element due to the resiliency of the contact structure.

23. The electronics system of claim 22 further comprising:

a connecting layer coupling the conductive element to internal circuitry within the first substrate;

a passivation layer disposed on the surface of the first substrate, the passivation layer having an opening at the conductive element of the first substrate; and

at least one electrically conductive layer disposed on the passivation layer and on the conductive element of the first substrate,

wherein the contact structure is electrically coupled through the at least one electrically conductive layer to the conductive element of the first substrate.

24. The electronics system of claim 23, wherein the conductive element comprises a terminal.

25. The electronics system of claim 23, wherein the tip portion comprises a pointed end.

26. The electronics system of claim 23, wherein the first substrate comprises a semiconductor device.

27. The electronics system of claim 23, wherein the contact structure comprises a metal layer.

28. The electronics system of claim 27, wherein the contact structure comprises a plurality of metal layers.

29. The electronics system of claim 23 further comprising a plurality of the contact structures, wherein adjacent contact structures are spaced between 2.5 microns and 2000 microns from each other.

30. The electronics system of claim 23, wherein the tip portion comprises a beveled peripheral edge.

31. The electronics system of claim 23, wherein the beam portion comprises a triangular shape.

32. The electronics system of claim 31, wherein the tip portion comprises a quadrilateral shape.

33. The electronics system of claim 32, wherein the tip portion comprises a rectangular shape.

34. The electronics system of claim 22, wherein the vertical distance is perpendicular to the surface of the substrate at which the conductive element is disposed.

35. The electronics system of claim 22, wherein the tip is disposed above the surface of the substrate at which the conductive element is disposed.

36. The electronics system of claim 22 further comprising a plurality of conductive contact structures each comprising a base portion attached to a conductive element disposed at the surface of the substrate, a tip portion displaced a vertical distance away from the surface of the substrate, and a beam portion between the base portion and the tip portion, wherein each of the contact structures is free standing and structurally distinct from the others of the contact structures.

37. The electronics system of claim 36 further comprising a stop structure disposed on the surface of the substrate, the stop structure comprising a plurality of openings, tip portions of the plurality of contact structures extending through the openings.

38. The electronics system of claim 37, wherein the stop structure covers substantially an entire portion of the surface of the substrate.

39. The electronics system of claim 36, wherein:

the base portion of each contact structure is generally rectangular,

the tip portion of each contact structure is generally rectangular, and

a spacing between centers of adjacent tip portions is less than a spacing between centers of adjacent base portions.