Studies of chipping mechanisms for dicing silicon wafers

Abstract

The purpose of this study was to investigate the chipping modes produced in the die edges of dicing silicon wafer using the thin diamond blades. The effects of dicing directions and different wafer types on the chipping size were studied. Furthermore, scratching tests were also used to assist the analysis of studying chipping conditions of the silicon wafer. The experimental results showed that the trace behaviors produced by the diamond indenter in the scratching test of silicon wafer can be divided into the three stages: rubbing, plastic deformation, cracking. The plastic pile up and crack of the scratching traces on the wafer mainly propagate along the development of the easiest slip direction family <110>. The chipping modes produced in dicing silicon wafer can be broadly classified as four types: (1) 30° chipping; (2) 60° chipping; (3) 90° chipping; (4) irregular chipping, which causes these mechanisms of chipping modes due to the meeting between the radial cracks of 30°, 60°, and 90° along the easiest slip direction family <110> and the lateral cracks along the easiest cleavage plane family {111}. When using the thin diamond blade diced on the (111) silicon wafer along the ${\left[ {\overline{1} 10} \right]}$ direction, the size of top chipping produced was smaller than that of along the ${\left[ {11\overline{2} } \right]}$ direction. Besides, for the (100) plane of silicon wafer, the size and the distribution of the chipping modes produced along the ${\left[ {\overline{1} 10} \right]}$ and ${\left[ {\overline{1} \overline{1} 0} \right]}$ directions were similar.