Impact of the substrate misorientation and its preliminary etching on the structural and optical properties of integrated GaAs/Si MOCVD heterostructures

Highlights: • Monocrystalline GaAs layer on Si(100) with reasonable crystalline perfection was successfully obtained and characterized. • GaAs/Si with off-angle ~3° toward [110] shows more strained lattice parameter than GaAs/Si with off-angle ~7°. • Preliminary etching for low off-angle or usage of high off-angle substrates is necessary for monocrystalline GaAs formation. • GaAs layers grown on Si substrate with off-angle ~3° layers seems to be suitable for further device fabrication. This is the first attempt to make a report regarding the control of the structural and optical functional characteristics of integrated GaAs/Si heterostructures owing to the employment of preliminary etched misoriented Si substrates. The epitaxial GaAs layer on silicon substrates with no formation of the antiphase domains can be grown using substrates deviating less than 4°–6° from the singular (100) plane or without the use of a transition layer of GaAs nano-stakes. Preliminary etching of the Si substrate made it easier to acquire an epitaxial GaAs film in a single-crystalline state with a significantly less relaxation factor MOCVD, which positively influences on the structural performance of the film. These data agree with the results of Infrared reflection spectroscopy as well as Photoluminescence and UV-Vis spectroscopy. The optical properties of the integrated GaAs/Si (100) heterostructures in the IR and UV spectral regions were also identified by means of the relaxation coefficients.