Patent · US Expired

Method for eliminating voiding in plated solder

US6780751B2 · kind B2 · utility

12Cited by
5References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 9, 2002
Grant dateAug 24, 2004
Priority date
Expiry dateOct 9, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/014
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for plating solder is provided. In accordance with the method, a die having a seed metallization thereon is provided. The seed metallization is microetched (85) with a solution comprising an acid and an oxidizer, thereby forming an etched seed metallization. An under bump metallization (UBM) is then electroplated (87) onto the etched seed metallization, and a lead-free solder composition, such as SnCu, is electroplated (91) onto the UBM. A method for reflowing solder is also provided, which may be used in conjunction with the method for plating solder. In accordance with this later method, the substrate is subjected to a seed metallization etch (137), followed by a microetch (141). A solder flux is then dispensed onto the substrate (147) and the solder is reflowed (149).

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