MICROELECTRONIC CONTACT STRUCTURE AND METHOD OF MAKING SAME

• US 20100093229A1
• Filed: 10/12/2009
• Published: 04/15/2010
• Est. Priority Date: 02/21/1996
• 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 8,033,838 B2
• Time in Patent Office: Days
• US Class Current: 439/816
• CPC Class Codes: G01R 1/06727 Cantilever beams
• CPC Class Codes: G01R 1/06738 related to tip portion
• CPC Class Codes: H01L 21/6835 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/68304 using temporarily an auxiliary support
• CPC Class Codes: H01L 2221/68359 used as a support during manufacture of interconnect decals or build up layers
• CPC Class Codes: H01L 2224/11003 for holding or transferring the bump preform
• CPC Class Codes: H01L 2224/111 Manufacture and pre-treatment of the bump connector preform
• CPC Class Codes: H01L 2224/11826 Physical vapour deposition [PVD], e.g. evaporation, or sputtering
• CPC Class Codes: H01L 2224/13017 being non uniform along the bump connector
• CPC Class Codes: H01L 2224/13018 comprising protrusions or indentations
• CPC Class Codes: H01L 2224/13019 at the bonding interface of the bump connector, i.e. on the surface of the bump connector
• CPC Class Codes: H01L 2224/13565 Only outside the bonding interface of the bump connector
• CPC Class Codes: H01L 2224/13582 Two-layer coating
• CPC Class Codes: H01L 2224/819 with the bump connector not providing any mechanical bonding
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01074 Tungsten [W]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• 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

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. A microelectronic spring contact element, comprising:

an elongate member of length “

L”

having a base end portion, a contact end portion opposite the base end portion, and a central body portion contiguous with each of the base and contact end portions;

the contact end portion is offset in a first direction from the central portion by a distance “

d1”

;

the base end portion is offset in a second direction opposite the first direction from the central portion by a distance “

d2”

;

wherein;

the base end portion is adapted in use to be mounted to a first electronic component; and

the tip end portion is adapted in use to make a pressure connection with a second electronic component.

2-53. -53. (canceled)