Stealth Dicing technology with SWIR laser realizing high throughput Si wafer dicing

Abstract

Stealth Dicing(SD) method is superior to blade dicing as well as other laser dicing methods such as laser ablation in terms of debris free and fully dry process. Therefore, SD is used to solve various problems in the dicing process, contributing to development of advanced devices and cost reduction. In this paper, we introduced a improved SD engine(SDE) that solves the problem that thick wafers, which have been pointed out as weak points of SD, require many laser scanning. The laser with the wavelength in the short wavelength infrared(SWIR) region was used and the spherical aberration that occurred when internal focusing of silicon was corrected by using LCoS-SLM. As a result, the crack propagation from the SD layer was significantly enhanced, achieving 3.5 times the throughput of the conventional SDE in a silicon wafer with 300 μm thickness.