Reduction of arsenic oxide contamination in molecular beam epitaxy vacuum chambers.

Molecular beam epitaxial films of GaAs and Al(x)Ga(1-x)As are degraded by the presence of arsenic oxide in the background gas spectrum. This memorandum discusses a technique for reducing the arsenic oxide contamination by baking the vacuum chamber under a flow of H(2). This technique is useful for an MBE system whose arsenic deposits have been oxidized from exposure to atmosphere. Initial results on the improvement of films grown in chambers with high arsenic oxide backgrounds through the use of 5x10(-7) Torr of H(2) is reported.