Elimination of anti-phase boundaries in a GaAs layer directly-grown on an on-axis Si(001) substrate by optimizing an AlGaAs nucleation layer

The direct growth of a III–V compound semiconductor on Si(001) is an unsolved problem for monolithically integrated photonic devices on the Si platform. Here, we report the growth of a high-quality GaAs layer on on-axis Si(001) substrates by MBE. A single domain GaAs layer was grown on top of a AlGaAs nucleation layer on a Si(001) substrate. By optimizing the Al content of the nucleation layer, anti-phase domains were self-eliminated at the GaAs layer. This result represents a key step towards the realization of monolithically integration of III–V devices on the Si platform using direct epitaxial growth.