Patent ID: 7883628

Claim:
A method for reducing the roughness of a free surface of a semiconductor-on-insulator semiconductor wafer, comprising: establishing a first atmosphere in an annealing chamber; replacing the first atmosphere in the annealing chamber with a second atmosphere that comprises a gas selected to and in an amount to substantially eliminate or reduce pollutants on a wafer; providing a semiconductor-on-insulator wafer having a free surface resulting from layer transfer; exposing the free surface of the wafer to the second atmosphere for a time and temperature sufficient to substantially eliminate or reduce pollutants thereon; replacing the second atmosphere in the annealing chamber with a third atmosphere of pure argon containing less than 1 ppm of other elements; and performing rapid thermal annealing on the wafer exposed to the third atmosphere in the annealing chamber to substantially reduce the roughness of the free surface of the wafer.