Land grid array (LGA) interposer utilizing metal-on-elastomer hemi-torus and other multiple points of contact geometries

• US 7,331,796 B2
• Filed: 03/01/2006
• Issued: 02/19/2008
• Est. Priority Date: 09/08/2005
• Status: Expired due to Fees

• Current Assignee: GlobalFoundries, Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Coteus, Paul W., Colgan, Evan G., Beaman, Brian S., Hougham, Gareth G., Oggioni, Stefano S., Vargas, Enrique
• Primary Examiner(s): Prasad; Chandrika
• Application Number:
  US11/365,366
• Publication Number:
  US 20070298624A1
• Time in Patent Office: 720 Days
• Field of Search: 439/66, 439/74, 439/86, 439/91, 439/178, 439/591
• US Class Current: 439/66
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73204 the bump connector being embedded into the layer connector
• 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: H01R 12/52 connecting to other rigid printed circuits or like structures
• CPC Class Codes: H01R 12/714 with contacts abutting directly the printed circuit; Button contacts therefore provided on the printed circuit
• CPC Class Codes: H05K 2201/0133 Elastomeric or compliant polymer
• CPC Class Codes: H05K 2201/0367 Metallic bump or raised conductor not used as solder bump
• CPC Class Codes: H05K 2201/09481 Via in pad; Pad over filled via
• CPC Class Codes: H05K 2201/09745 Recess in conductor, e.g. in pad or in metallic substrate
• CPC Class Codes: H05K 2201/10378 Interposers
• CPC Class Codes: H05K 2201/10734 Ball grid array [BGA]; Bump grid array
• CPC Class Codes: H05K 3/326 the printed circuit having integral resilient or deformable parts, e.g. tabs or parts of flexible circuits H05K3/365 takes precedence
• CPC Class Codes: H05K 3/4007 Surface contacts, e.g. bumps H05K3/4092 takes precedence; deposition of finish layers on pads H05K3/24; forming solder bumps H05K3/3457
• CPC Class Codes: H05K 7/1061 co-operating by abutting
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49121 Beam lead frame or beam lead device
• CPC Class Codes: Y10T 29/49124 On flat or curved insulated base, e.g., printed circuit, etc.
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49128 Assembling formed circuit to base
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49147 : Assembling terminal to base
• CPC Class Codes: Y10T 29/49149 : by metal fusion bonding
• CPC Class Codes: Y10T 29/49151 : by deforming or shaping
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49158 : with molding of insulated base
• CPC Class Codes: Y10T 29/49165 : by forming conductive walled aperture in base
• CPC Class Codes: Y10T 29/49204 : Contact or terminal manufacturing
• CPC Class Codes: Y10T 29/49208 : by assembling plural parts
• CPC Class Codes: Y10T 29/49213 : Metal
• CPC Class Codes: Y10T 29/49218 : with deforming
• CPC Class Codes: Y10T 29/49222 : forming array of contacts or terminals

Abstract

A land grid array (LGA) interposer structure, including an electrically insulating carrier plane, and at least one interposer mounted on a first surface of said carrier plane. The interposer possesses a hemi-toroidal configuration in transverse cross-section and is constituted of a dielectric elastomeric material. A plurality of electrically-conductive elements are arranged about the surface of the at least one hemi-toroidal interposer and extend radically inwardly and downwardly from an uppermost end thereof into electrical contact with at least one component located on an opposite side of the electrically insulating carrier plane. Provided is also a method of producing the land grid array interposer structure.

Claims

1. A land grid array (LGA) interposer structure, comprising an electrically insulating carrier pad, at least one interposer mounted on a first surface of said carrier pad, said interposer selectively having a hemi-toroidal, conical, dome-shaped conic section, generally cylindrical or hemi-spherical configuration in transverse cross-section and being constituted of a dielectric elastomeric material;

a plurality of electrically-conductive elements being arranged about the surface of said at least one hemi-toroidal interposer and extending radially inwardly and downwardly from an uppermost end thereof into electrical contact with at least one component located on an opposite side of said electrically insulating carrier pad, said at least one component comprising at least one hemi-toroidal interposer mounted on said opposite side of said carrier pad and which is identical to and in an inverted relationship with said first-mentioned at least one hemi-toroidal interposer, an electrically-conductive solder pad member extending through at least one via and having portions extending in surface contact with upper and lower surfaces of said insulating carrier pad, said at least one hemi-toroidal interposer and said at least one inverted hemi-toroidal interposer being at least partially located on, respectively, the upper and lower surface of said insulating carrier pad, whereby the electrically-conductive elements are in contact with the respective surfaces on said solder pad.

2. An interposer structure as claimed in claim 1, wherein said electrically-insulating carrier pad has said at least one through-extending via formed therein, said electrically-conductive electrically-conductive elements comprising metallic strips forming electrical connections between said first-mentioned at least one hemi-toroidal interposer and said further at least one inverted hemi-toroidal interposer.

3. An interposer structure as claimed in claim 2, wherein said metallic strips each extend to provide electrically-conductive paths between the uppermost end of said at least one hemi-toroidal interposer on the first surface of said carrier pad and the lowermost end of the at least one inverted hemi-toroidal interposer on the opposite side of said carrier pad.

4. An interposer structure as claimed in claim 1, wherein said electrically-conductive elements comprise metallic strips extending into contact with the solder pad portion on the upper surface of said solder pad, and the components on the opposite side of said insulating carrier pad with the solder pad portion on the upper surface of said solder pad, and the components on the opposite side of said insulating carrier pad being in electrically-conductive contact with the solder pad portion on the lower surface of said insulating pad portion.

5. An interposer structure as claimed in claim 1, wherein said at least one interposer is constituted of a dielectric elastomeric material.

6. An interposer structure as claimed in claim 5, wherein said elastomeric material comprises a moldable polymer having rubber-like resilient characteristics.

7. An interposer structure as claimed in claim 6, wherein said polymer is selected from the group of materials consisting of silicon rubber, siloxane, PDMS, polyurethane, polybutadiene and copolymers thereof, polystyrene and copolymers thereof, acrylonitrile and copolymers thereof, and epoxides and copolymers thereof.