Photoluminescence of AlxGa1−xAs grown by molecular beam epitaxy

Reduction of background oxygen containing species, higher substrate temperature, and low arsenic fluxes during growth have all been found critical to improve the luminescence of molecular beam epitaxy AlxGa1−xAs alloys. Attention to these parameters has allowed greatly improved quality films to be grown which show strong exciton recombination for the first time. The main unintentional acceptor impurity was then found to be carbon.