Patent ID: 8696197
Filing Date: 2014-04-15
Classification: G01J,G01N,H01L

Abstract:
1. A method for controlling a heating process for substrates in a thermal processing chamber, comprising: emitting a light onto a first radial position and a second radial position on a substrate, the substrate having a first surface and a second opposite surface separated from the first surface by a thickness; directing the light through an optical pathway that includes at least one optical device that is a separate structure from the substrate that separates light reflected from the first surface from light reflected from the second surface; determining, at a location outside of the thermal processing chamber, one or more optical characteristics of the substrate based on light detected from the first surface of substrate; transferring the substrate to the thermal processing chamber; and controlling one or more heating devices in the thermal processing chamber with a controller based at least in part on the one or more optical characteristics of the substrate to achieve a temperature distribution across the substrate.