GaSb/GaP compliant interface for high electron mobility AlSb/InAs heterostructures on (001) GaP

We report on the epitaxial growth of an AlSb/InAs heterostructure on a (001) GaP substrate. We investigate the conditions for the most efficient relaxation of GaSb islands on GaP. In particular, we show that the GaP surface treatment and the growth temperature are crucial for the formation of a two-dimensional periodic array of 90° misfit dislocations at the episubstrate interface. With this relaxation process, an AlSb/InAs heterostructure exhibiting a room temperature mobility of 25 500 cm2 V−1 s−1 on GaP is demonstrated. This result paves the way to the integration of Sb-based devices on Si substrates through the use of GaP/Si templates.