Patent · US Expired

Flexible circuit board for ball grid array semiconductor package

US5864470A · kind A · utility

53Cited by
8References
17Claims
0Family size

Assignees

Inventors

Key dates

Filing dateJun 25, 1997
Grant dateJan 26, 1999
Priority date
Expiry dateJun 25, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/181
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A flexible circuit board for a ball grid array semiconductor package including a flexible resin film, a plurality of electrically conductive traces formed on an upper surface of the resin film, the conductive traces having solder ball pads, and a die flag including a semiconductor chip paddle located on a central portion of the circuit board, the chip paddle having a plurality of heat-discharging and grounding solder ball pads, and a plurality of lattice-shaped traces adapted to electrically connect the solder ball pads, the traces being shaped into a lattice to prevent a bleed-out of a silver-filled epoxy resin, a ground bonding rim located around the chip paddle, and a plurality of radial traces adapted to electrically connect the chip paddle to the ground bonding rim, and the flexible resin film being perforated to define solder ball lands on lower surfaces of the solder ball pads. Since the semiconductor chip paddle has an enlarged opened portion, it is possible to minimize the gold plated region, thereby greatly reducing the manufacturing costs. It is also possible to minimize a deformation of the package caused by mechanical stress generated due to a difference in thermal exp…

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