Molecular beam epitaxy growth of GaAs on an offcut Ge substrate

Molecular beam epitaxy growth of GaAs on an offcut Ge (100) substrate has been systemically investigated.A high quality GaAs/Ge interface and GaAs film on Ge have been achieved.High temperature annealing before GaAs deposition is found to be indispensable to avoid anti-phase domains.The quality of the GaAs film is found to strongly depend on the GaAs/Ge interface and the beginning of GaAs deposition.The reason why both high temperature annealing and GaAs growth temperature can affect epitaxial GaAs film quality is discussed.High quality In 0.17 Ga 0.83 As/GaAs strained quantum wells have also been achieved on a Ge substrate.Samples show flat surface morphology and narrow photoluminescence line width compared with the same structure sample grown on a GaAs substrate.These results indicate a large application potential for Ⅲ-Ⅴ compound semiconductor optoelectronic devices on Ge substrates.