Effect of Arsenic Source on the Growth of High Purity GaAs by Molecular Beam Epitaxy

We report growth of ultra pure GaAs by molecular beam epitaxy (MBE) and show that the arsenic source has a dramatic effect on the purity. With every thing else the same, by changing the arsenic source from 6N grade double refined chunks to a 7N grade slug which closely fits the 35 cm sup 3 crucible, the deep electron trap and the residual acceptor densities were reduced by nearly two orders of magnitude.