Substrate temperature control in an ALD reactor

Abstract

A deposition system includes a process chamber for conducting an ALD process to deposit layers on a substrate. An electrostatic chuck (ESC) retains the substrate. A backside gas increases thermal coupling between the substrate and the ESC. The ESC is cooled via a coolant flowing through a coolant plate and heated via a resistive heater. Various arrangements are disclosed.

What is claimed is:  
     
         1 . A system for controlling the temperature of a substrate in a process chamber comprising: 
 an electrostatic chuck assembly for retaining a substrate on said chuck assembly by electrostatic attraction, said substrate, when retained by said chuck assembly, forming a backside gas volume bounded by a backside surface of said substrate; and    a gas inlet leading to said backside gas volume for supplying a backside gas to said backside gas volume for providing a thermal transfer between said chuck assembly and said backside surface of said substrate.