Area selective growth of GaAs by migration‐enhanced epitaxy

Application of migration‐enhanced deposition sequence to area selective growth of GaAs and other III–V compound semiconductors makes it possible to achieve well‐defined area selective growth even using solid source molecular beam epitaxy. Successful growth of small disks and other structures has been performed on SiO 2 masked (111)A and (111)B substrates at temperatures around 590 °C. General rule for facets formation suggests that the facet angle is quite sensitive to the V/III flax ratio as well as the substrate orientation. To create vertical $ \bar 1 $ facets around the structures at relatively low V/III flux ratios, (111)A substrates is much more preferable to (111)B substrate. However, high density of hillocks emerges on the structures grown on (111)A substrate. It is found that the hillocks are caused by the stacking faults. The density of hillocks has been dramatically reduced by depositing As in the Ga deposition period. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)