Ceramic column grid array (CCGA) module for a high performance work station application

Abstract

A multi-layer ceramic (MLC) substrate has been developed to package a 335 mm/sup 2/ silicon chip with a large number of transistors (15 million). The flip-chip required a package which can support a large number of I/O, and ability to cool 30 watts of power at 135 MHz. The large package pincount of 1088 led to the choice of a 42.5 mm substrate with a 1.27 mm pitch solder column grid array. In this paper, the chip and package attributes are described. A highly conductive thermal paste with a conductivity of 3.8 watt/m-deg. has been developed to provide an efficient thermal path from the flip-chip to the Al cap used on this package. Finally, the excellent reliability achieved by the column grid array connection to the second level organic card is discussed.