Antiphase domains in GaAs grown by MOCVD on Si-on-Insulator.

Distinct antiphase domain structures in GaAs epitaxial layers grown on a Si/Si0 sub 2/ Si-substrate structure by MOCVD have been revealed by using a silicon etchant (HF/HNO sub 3). The antiphase is characterized by the [011] oriented etching textures which rotate 90 degrees between adjacent domains. The corresponding lattice rotation is further confirmed by a convergent beam electron diffraction technique. The size of the antiphase domains is found to increase with increasing film thickness and to grow upon annealing at temperatures above 700C. The maximum size of the domain, however, is found to be limited by the film thickness. The majority of the domain boundary lines revealed by chemical etching on the (100) surface do not correspond to any crystalline orientation. Only small segments are found to orient along [011], [010], [021] and, occasionally, [031] and [041] directions.