The effect of a Sb and Ga intermediate layer on the interfacial layer properties of epitaxial GaSb on GaAs grown by metalorganic chemical vapor deposition.

Abstract A method for the growth of high quality GaSb epilayer on GaAs (001) substrate is demonstrated in this study. It is found that a superior GaSb/GaAs interface can be obtained by depositing a thin Sb-precursor layer on the GaAs substrate containing a GaAs buffer layer. It is suggested that the growth occurs via the interface misfit (IMF) growth mode. Without this treatment, GaSb epilayer may grow according to the Stranski–Krastanov mechanism or via a blend of the Stranski–Krastanov and IMF mechanisms, leading to an inferior GaSb/GaAs interface. This could be due to the intermixing of anions, leading to the turbulent composition and misfit dislocation distribution at the heterointerface. It appears that with the addition of a Sb layer, IMF arrays can be formed at GaSb/GaAs interface resulting in superior GaSb layer without the need for changing the growth parameters. Highlights • Impact of Ga- and Sb-based passivation at the GaSb/GaAs interface was studied. • Sb-based passivation relaxes the GaSb/GaAs lattice strain. • Sb-based passivation reduces threading dislocations at the GaSb epilayer. • Sb-based passivation prevents the interdiffusion at the GaSb/GaAs interface. [ABSTRACT FROM AUTHOR]