Wafer temperature measurement in PVD systems using the Co–Si reaction

Abstract

It is becoming increasingly important to control the wafer temperature during IC processing, e.g. PVD. To measure the wafer temperature in PVD systems it is possible to use the Co–Si reaction. The difference in sheet resistance of the Co–Si phases, which form at different temperatures, is used to measure maximum wafer temperature in a PVD chamber. The maximum wafer temperature and the time it takes to reach this temperature are determined by the heat transfer between wafer and chuck. Wafer temperature measurements have been performed using different clamping configurations. Spring clamping of wafers and electrostatic chucks give the best results.