Patent ID: 6939579

Claim:
A method for growing a thin film on a substrate by exposing the substrate in a reaction chamber defined by a plurality of walls to alternate surface reactions of vapor-phase reactants, comprising: controlling a chamber wall temperature of at least those portions of the chamber walls that are exposed to the vapor-phase reactants; loading the substrate onto a substrate support structure inside the reaction chamber; controlling a substrate support temperature independently of the chamber wall temperature; and alternately and sequentially feeding at least two vapor phase reactants into the reaction chamber wherein the substrate support temperature is maintained at a first temperature and the chamber wall temperature is maintained at a second temperature different from the substrate support temperature and, wherein the first temperature and the second temperature are within an atomic layer deposition (ALD) temperature window such that there is atomic layer deposition (ALD) growth on the substrate and the chamber wall and the difference between the first temperature and the second temperature is selected to maintain a lower rate of atomic layer deposition (ALD) film growth upon the chamber walls as compared to the substrate.