Patent · US Expired

Structure, materials, and methods for socketable ball grid

US6120885A · kind A · utility

14Cited by
25References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 30, 1998
Grant dateSep 19, 2000
Priority date
Expiry dateJun 30, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/256
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A socketable ball grid array structure is disclosed which comprises mechanically rigid (compared to solder alloys) balls coated with noble contact metals joined to the chip carrier terminals by means of a novel electrically conducting adhesive. Because of the nature of the filler that includes conducting particles with a fusible coating and the appropriate selection of the polymer resin used in the adhesive, the balls are attached to the module in a compliant and resilient manner while leaving the majority of the bottom surface of the balls pristine. The array of balls can therefore be plugged into mating sockets in a printed circuit board forming a demountable contact. This facilitates easy removal of the socketable BGA from a board for repair or upgrade purposes as well as allows ease of plugging and unplugging of these BGA's into test and burn-in boards.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.