Microelectronic contact structure and method of making same

• US 7,601,039 B2
• Filed: 07/11/2006
• Issued: 10/13/2009
• Est. Priority Date: 11/16/1993
• Status: Expired due to Fees

• Current Assignee: FormFactor Incorporated
• Original Assignee: FormFactor Incorporated
• Inventors: Mathieu, Gaetan L., Eldridge, Benjamin N., Grube, Gary W., Khandros, Igor Y.
• Primary Examiner(s): Abrams; Neil
• Application Number:
  US11/456,568
• Publication Number:
  US 20060237856A1
• Time in Patent Office: 1,190 Days
• Field of Search: 439/81, 439/66, 439/894, 298/42, 298/43, 298/46, 298/74, 174/260, 174/254, 156/233, 156231-232
• US Class Current: 439/894
• CPC Class Codes: B23K 2101/38 Conductors
• CPC Class Codes: G01R 1/06727 Cantilever beams
• CPC Class Codes: G01R 1/06744 Microprobes, i.e. having dimensions as IC details
• CPC Class Codes: G01R 3/00 Apparatus or processes specially adapted for the manufacture or maintenance of measuring instruments , e.g. of probe tips
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 23/4951 Chip-on-leads or leads-on-chip techniques, i.e. inner lead fingers being used as die pad
• 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 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01015 Phosphorus [P]
• 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 2924/01042 Molybdenum [Mo]
• CPC Class Codes: H01L 2924/01045 Rhodium [Rh]
• CPC Class Codes: H01L 2924/01046 Palladium [Pd]
• CPC Class Codes: H01L 2924/01047 Silver [Ag]
• CPC Class Codes: H01L 2924/01049 Indium [In]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/01078 : Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 : Gold [Au]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/1433 : Application-specific integrated circuit [ASIC]
• CPC Class Codes: H01L 2924/3011 : Impedance
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H01R 12/57 : surface mounting terminals
• CPC Class Codes: H05K 3/4092 : Integral conductive tabs, i.e. conductive parts partly detached from the substrate
• CPC Class Codes: Y10T 29/49147 : Assembling terminal to base
• CPC Class Codes: Y10T 29/49149 : by metal fusion bonding
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49204 : Contact or terminal manufacturing

Abstract

An electronic interconnection apparatus can include a sacrificial substrate, which can include first trenches and second trenches formed in the sacrificial substrate. The first trenches can be disposed below a surface of the sacrificial substrate, and the second trenches can be disposed below the first trenches. First sidewalls can connect the surface and the first trenches, and the first sidewalls can be angled with respect to the surface and the first trenches. Second sidewalls can connect the first trenches and the second trenches, and the second sidewalls can be angled with respect to the first trenches and the second trenches. Spring contact elements can reside upon the sacrificial substrate. Each of the spring contact elements can have a first portion disposed on the surface, a second portion disposed on one of the first trenches, and a third portion disposed on one of the second trenches.

Claims

1. Electronic interconnection apparatus, comprising:

a sacrificial substrate comprising;

a surface,

a plurality of first trenches formed in the sacrificial substrate and disposed below the surface,

a plurality of first sidewalls each connecting the surface and one of the first trenches, wherein each of the first sidewalls is angled with respect to the surface and the one of the first trenches,

a plurality of second trenches formed in the sacrificial substrate and disposed below the first trenches,

a plurality of second sidewalls each connecting one of the first trenches and one of the second trenches, wherein each of the second sidewalls is angled with respect to the one of the first trenches and the one of the second trenches; and

a plurality of spring contact elements residing upon the sacrificial substrate, wherein each of the spring contact elements comprises a first portion disposed on the surface, a second portion disposed on one of the first trenches, and a third portion disposed on one of the second trenches.

2. Electronic interconnection apparatus, according to claim 1, wherein:

the sacrificial substrate has a coefficient of thermal expansion that substantially equals a coefficient of thermal expansion of silicon.

3. Electronic interconnection apparatus, according to claim 1, wherein:

the sacrificial substrate comprises a material selected from the group consisting of silicon, aluminum, copper, ceramic, copper-invar-copper and aluminum-alumina-aluminum.

4. Electronic interconnection apparatus, according to claim 1, wherein the sacrificial substrate further comprises a plurality of features each of which extends into one of the second trenches.

5. Electronic interconnection apparatus, according to claim 4, wherein each of the spring contact elements further comprises a topological feature on the third portion, the topological feature disposed in one of the features.

6. Electronic interconnection apparatus, according to claim 5, wherein, for each of the spring contact elements, the first portion comprises a first end portion, the third portion comprises a second end portion, and the second portion comprises a central portion between the first end portion and the second end portion.

7. Electronic interconnection apparatus, according to claim 1, wherein, for each of the spring contact elements, the first portion comprises a first end portion, the third portion comprises a second end portion, and the second portion comprises a central portion between the first end portion and the second end portion.

8. Electronic interconnection apparatus, according to claim 1, wherein the sacrificial substrate comprises a layer of material disposed between the spring contact elements and the surface, the first trenches, and the second trenches.

9. Electronic interconnection apparatus, according to claim 8, wherein removal of the layer of material releases the spring contact elements from the sacrificial substrate.

10. Electronic interconnection apparatus, according to claim 1, wherein the first trenches and the second trenches are substantially parallel to the surface of the sacrificial substrate.

11. Electronic interconnection apparatus, according to claim 10, wherein, for each of the spring contact elements, the first portion and the third portion are substantially parallel to the second portion.

12. Electronic interconnection apparatus, according to claim 1, wherein each of the first sidewalls is angled with respect to the surface and the one of the first trenches such that the first sidewall is neither parallel nor perpendicular to the surface or the one of the first trenches.

13. Electronic interconnection apparatus, according to claim 12, wherein each of the second sidewalls is angled with respect to the one of the first trenches and the one of the second trenches such that the first sidewall is neither parallel nor perpendicular to the one of the first trenches or the one of the second trenches.

14. Electronic interconnection apparatus, according to claim 1, wherein:

the sacrificial substrate comprises a crystalline structure, and

each of the first sidewalls is angled with respect to the surface and the one of the first trenches at an angle that corresponds to the crystalline structure of the sacrificial substrate.

15. Electronic interconnection apparatus, according to claim 14, wherein the sacrificial substrate comprises silicon, and the crystalline structure is of silicon.

16. Electronic interconnection apparatus, according to claim 14, wherein each of the second sidewalls is angled with respect to the one of the first trenches and the one of the second trenches at an angle that corresponds to the crystalline structure of the sacrificial substrate.

17. Electronic interconnection apparatus, according to claim 16, wherein the sacrificial substrate comprises silicon, and the crystalline structure is of silicon.

18. Electronic interconnection apparatus, according to claim 1, wherein, in use, the spring contact elements can be mounted, en masse, to terminals of an electronic component.

19. Electronic interconnection apparatus, according to claim 18, further comprising:

a release mechanism incorporated into the sacrificial substrate which, in use, permits the sacrificial substrate to be removed after the spring contact elements are mounted to the terminals of the electronic component.