Patent · US Expired

Method for enhancing fatigue life of ball grid arrays

US6158644A · kind A · utility

29Cited by
8References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 30, 1998
Grant dateDec 12, 2000
Priority date
Expiry dateApr 30, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/2991
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

This invention relates to a solder structure which provides enhanced fatigue life properties when used to bond substrates particularly at the second level such as BGA and CGA interconnections. The solder structure is preferably a sphere or column and has a metal layer wettable by solder and the structure is used to make solder connections in electronic components such as joining an electronic module such as a chip connected to a MLC which module is connected to a circuit board. The solder structure preferably has an overcoat of solder on the metal layer to provide a passivation coating to the metal layer to keep it clean from oxidation and corrosion and also provide a wettable surface for attachment of the solder structure to solder on the pads of the substrate being bonded.

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