Patent · US Expired

Bump forming apparatus

US5573170A · kind A · utility

13Cited by
4References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 9, 1994
Grant dateNov 12, 1996
Priority date
Expiry dateDec 9, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/014
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

In an apparatus for punching a metallic sheet to stamp out a bump and bonding it to a substrate, an AuSn sheet is heated to above a softening point thereof by a heater. A solenoid is energized to cause a punch and a die to stamp out a bump from the AuSn sheet. The bump is directly bonded to a substrate. The punch is made up of a shank portion and a punch portion. A punch holder for guiding the shank portion and punch portion with high accuracy molded integrally with the die. The punch is connected to the solenoid with the intermediary of a damper spring. When the bump hits against the substrate, the damper spring prevents it from chipping off or cracking due to an impact. Subsequently, another solenoid is energized to move the punch further downward, thereby pressing the bump against the substrate for a sufficient period of time.

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