Ejectorless method for die attach pick up for cracking improvement on thin high-aspect ratio die

Abstract

The demand for producing small, thin, and light electronic devices is increasing. As a result, the design and assembly of electronic packaging technology have been developed. To meet the ever-increasing technology requirements, the critical process in the semiconductor packaging include wafer back grinding, sawing, and die attach. Given that the die thickness is lower than the previous ones, the risk of die cracking failures, which can lead to device malfunction, becomes high. In the die attach process, the ejector pin has an effect during the pick and place processes. Such impact may result in micro dented mark or micro crack underneath the die, which becomes the weakened point throughout the entire process. In this study, an ejectorless system for the die pick and place during the die attach process has been designed and evaluated. The methodology of using ejector pin is replaced by heated static pillar inside cavity for die platform before being picked up. Vacuum is used to stabilize the die, and heat is applied to soften the sawing tape and weaken the adhesion of the die to the sawing tape. Results show that the critical issues of die crack for thin high aspect ratio die are resolved by using the proposed method for the die pick during the die attach process. In conclusion, the semiconductor packaging advances the pick-up technology solution for the challenging material, which is needed for the current miniaturization market trend and demand.