Effects of temperature and substrate miscut on the crystalline quality of metamorphic AlInAs layers grown on GaAs substrate

We have investigated the effects of temperature and substrate miscut on the crystalline quality of metamorphic AlInAs layers grown on a GaAs substrate by metal organic chemical vapor deposition (MOCVD). The AlInAs layers grown at 700 °C show a much better crystalline quality than the ones grown at 675 °C, because a high temperature can suppress phase separation and enhance the glide velocity of dislocations during the strain relaxation process. Compared with the miscuts of 2° and 7°, the 15° miscut is more effective in suppressing phase separation during the growth of the AlInAs buffers. Theoretical calculations show that the miscut will facilitate the strain relaxation by dislocation gliding. These results indicate that a high growth temperature and a large miscut will improve the quality of the metamorphic AlInAs layers grown on the GaAs substrate by MOCVD.