Microelectronic Contact Structure And Method Of Making Same

• US 20060237856A1
• Filed: 07/11/2006
• Published: 10/26/2006
• Est. Priority Date: 11/16/1993
• Status: Active Grant

• Current Assignee: FormFactor Incorporated
• Original Assignee: FormFactor Incorporated
• Inventors: Mathieu, Gaetan L., Eldridge, Benjamin N., Grube, Gary W., Khandros, Igor Y.
• Granted Patent: US 7,601,039 B2
• Time in Patent Office: Days
• US Class Current: 257/784
• 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

Spring contact elements are fabricated by depositing at least one layer of metallic material into openings defined on a sacrificial substrate. The openings may be within the surface of the substrate, or in one or more layers deposited on the surface of the sacrificial substrate. Each spring contact element has a base end portion, a contact end portion, and a central body portion. The contact end portion is offset in the z-axis (at a different height) than the central body portion. The base end portion is preferably offset in an opposite direction along the z-axis from the central body portion. In this manner, a plurality of spring contact elements are fabricated in a prescribed spatial relationship with one another on the sacrificial substrate. The spring contact elements are suitably mounted by their base end portions to corresponding terminals on an electronic component, such as a space transformer or a semiconductor device, whereupon the sacrificial substrate is removed so that the contact ends of the spring contact elements extend above the surface of the electronic component. In an exemplary use, the spring contact elements are thereby disposed on a space transformer component of a probe card assembly so that their contact ends effect pressure connections to corresponding terminals on another electronic component, for the purpose of probing the electronic component.

Claims

1-37. -37. (canceled)

38. Electronic interconnection apparatus, comprising:

a sacrificial substrate; and

a plurality of spring contact elements residing upon the sacrificial substrate;

wherein, in use, the spring contact elements can be mounted, en masse to terminals of an electronic component.

39. Electronic interconnection apparatus, according to claim 38, wherein:

the sacrificial substrate is a material that matches the coefficient of thermal expansion of silicon.

40. Electronic interconnection apparatus, according to claim 38, wherein:

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

41. Electronic interconnection apparatus, according to claim 38, 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.

42-53. -53. (canceled)