Patent · US Expired

Mold for ball grid array semiconductor package

US5971734A · kind A · utility

18Cited by
10References
29Claims
0Family size

Assignees

Inventor

Key dates

Filing dateSep 19, 1997
Grant dateOct 26, 1999
Priority date
Expiry dateSep 19, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/3862
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A mold for BGA semiconductor packages which includes a height adjusting member adapted to adjust the height of the top cavity insert of the top mold or the bottom cavity insert of the bottom mold, an elastic member disposed between the height adjusting member and associated insert, clamping regions of different heights formed at its top or bottom cavity insert, or air vents having a width and depth of an optimum ratio to the area and depth of cavities, thereby being capable of maintaining an optimum and uniform clamping pressure between the top and bottom molds for a variety of PCB strips having a thickness deviation among different portions thereof or having various average thicknesses, upon molding resin encapsulants on those PCB strips, thereby achieving an improvement in the quality of finally produced packages while preventing a sweeping phenomenon of bonding wires electrically connecting a semiconductor chip to conductive traces.

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