Spectroscopic Measurements of Silicon Wafer Thickness for Backgrinding Process

Abstract

The optical microgauge system by means of near-infrared spectroscopic measurements was proposed as the thickness monitoring tool in the silicon wafer thinning process. The Fabry-Pelot interferometry and Beer’s law were employed as the principles of the system for extracting the wafer thickness from optical spectroscopic system prototyped in this study. The specifications of the system such as the thickness range and resolution were examined on the prototyped system. The filed test verified the developed system available of monitoring Si wafer as thin as 5 mm.