Patent · US Expired

Selectively coating bond pads

US6403457B2 · kind B2 · utility

11Cited by
7References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 25, 1999
Grant dateJun 11, 2002
Priority date
Expiry dateAug 25, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05K2203/072
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Solder ball bond pads and wire bond pads may be selectively coated so that the wire bond bond pads have a thicker gold coating than the solder ball bond pads. This may reduce the embrittlement of solder ball joints while providing a sufficient thickness of gold for the wire bonding process. In general, gold coatings are desirable on electrical contact surfaces to prevent oxidation. However, the thickness of gold which is necessary on solder ball bond pads may be less and excessive gold may be disadvantageous. Thus, by masking the solder ball bond pads during the gold coating of the wire bond bond pads, a differential gold thickness may be achieved which is more advantageous for each application.

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