MBE growth of high quality InAsSb thin films on GaAs substrates with GaSb as buffer layers.

• InAs interface layer can neutralize the accumulation of Sb elements in the GaSb/InAsSb interface. • The nucleation layer with low growth rate facilitated the coalescence process of mound during the growth of InAsSb layer. • The AlSb nucleation layer changed the generation mode of edge dislocations and reduced the dislocation density. • AlSb/GaSb SL buffer layer inhibited the propagation of dislocation by intersecting and closing them. In this account, a series of InAsSb thin films were grown on GaAs substrates with GaSb as buffer layer by MBE, the effect of nucleation layer grown under different conditions on the quality of InAsSb thin films was studied, and the inhibition effect of AlSb/GaSb superlattice structure (SLS) on defect propagation in heteroepitaxy was evaluated. In this process, the corresponding Sb/As BEP flux ratio changes of As/In BEP flux ratio are studied. The sensitivity of Sb/As BEP flux ratio to As beam change is eliminated by using locked As beam value and Sb/As BEP flux ratio, which improves the repeatability of epitaxial material component control. At the same time, the Sb content of the GaSb/InAsSb interface could be accurately tuned by controlling the opening sequence and time of the sources cell shutter. Released the increase of strain at the interface caused by too large Sb component. It can be used to control the composition of InAsSb materials. [ABSTRACT FROM AUTHOR]