Browse Prior Art Database

Circuit Module having Substrate with Center Hole

IP.com Disclosure Number: IPCOM000051989D
Original Publication Date: 1981-Apr-01
Included in the Prior Art Database: 2005-Feb-11

Publishing Venue

IBM

Related People

Authors:
Allen, GW Merritt, CR Phillips, GC Rivenburgh, DL Wu, WW [+details]

Abstract

Some modules include a semiconductor chip with laser-weldable connectio points and a ceramic substrate with a square center hole. The chip is mounted on the substrate with peripheral connection points on the chip connected by solder balls to pads around the periphery of the hole and with weldable points on the chip accessible through the center hole for the laser-weld operations. In manufacturing the module, the center hole may be formed initially and temporarily plugged during solder dip operations. Cracking which sometimes occurs around the center hole has been traced to the fact that the center hole may permit excessive heat to be transferred to the substrate.