Ceramic column grid array for flip chip applications

Ceramic Column Grid Array (CCGA) technology was introduced by IBM several years ago. The purpose of the Column Grid Array (CGA) technology was its improved reliability compared to the Ball Grid Array due to height and compliance. This paper describes several process improvements in fabricating the columns onto the substrates. These improvement's include attaching the columns to the ceramic substrate using no clean flux and the ability to rework cast columns during the fabrication of the module. In addition, stress testing was completed to validate the use of the Coffin-Manson equation in predicting the fatigue life as a function of column length, as well as a bridge between two accelerated thermal cycling (ATC) conditions, 0-100/spl deg/C and -55-125/spl deg/C.