4 mil DAF Die Thickness Sawing Capability Study

The drive for package thickness reduction has created new processing challenges with regards to thin wafer handling. While back grinding and die attach film (DAF) lamination are now established processes to 8 mil but dicing DAF-laminated wafers with wafer thickness of 4 mils and below is a significant challenge. This paper reports the successful introduction of 4 mil wafer dicing; with and without DAF lamination. This capability involves work in evaluating different saw parameters such as feed speed, RPM and blade types. Detail understanding in the fundamental of blade properties and characteristics is crucial to the success of this study. The results show that for thin die a dual pass saw process gives better results than a conventional single pass process. An innovative Step cut sawing is proposed. In this paper, an insight of 30 um sawing feasibility is also provided.