Growth of GaAs on Polycrystalline Germanium Substrates Prepared via Aluminum-Induced Crystallization

Polycrystalline germanium substrates with an average grain size >600 nm have been achieved on silicon substrates with 500 nm thermally grown silicon dioxide, using a process called aluminum-induced crystallization. Double heterostructures were grown by metal-organic vapor phase epitaxy on these polycrystalline germanium substrates, as well as commercial large-grain polycrystalline germanium substrates and monocrystalline germanium substrate as baselines. Four temperatures were explored for the gallium arsenide nucleation layer in the double heterostructure, with all other growth conditions remaining constant.