The influence of gallium ingot cleaning procedures on the carbon impurity level in molecular beam epitaxy GaAs

Abstract
Carbon impurity in molecular beam epitaxy (MBE) grown GaAs was traced to contamination of the gallium source. The gallium was contaminated by abrasion of the polyethylene wrapping around the ingots during shipment. A cleaning procedure for removing the surface contamination of the ingots is described and results are given that show a reduced carbon impurity level in GaAs samples grown after gallium cleaning.