Processes for Thinning and Polishing Highly Warped Die to a Nearly Consistent Thickness: Part I

This article, the first in a multi-part series, describes how to finely control remaining silicon thickness (RST) through the correction of mechanical surface profiles using multipoint thickness measurements. It explains why multipoint thickness measurements are necessary and discusses the realities of silicon thickness measurements. With careful processing, cleaning, and RST measurements, samples can be reliably processed to a 50 μm thickness with a variation of +/- 2.5 μm across the majority of the die.