Patent · US Expired

Method of forming solder bump and method of mounting the same

US6189771A · kind A · utility

29Cited by
3References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 7, 1999
Grant dateFeb 20, 2001
Priority date
Expiry dateOct 7, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P70/50
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A solder bump formation method and solder bump mounting method for forming a solder bump by soldering a solder ball 9 onto an electrode 2 provided at the bottom of a cavity 3 on a substrate 2 which has an opening shape through which the solder ball 9 cannot go. Metal paste 5, containing metal having a higher liquidus temperature than that of solder used for the solder ball 9, is filled into the cavity 3. The solder ball 9 is placed on the cavity 3, and then heated to the temperature higher than the liquidus temperature of the solder ball 9. During the heating process, metal in the metal paste 5 remains unmelted in the cavity 3 when the solder ball 9 melts. This enables the metal to direct the melted solder to the electrode 2 at the bottom of the cavity 3, achieving good soldering.

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