SELECTIVE AREA EPITAXY OF GASB BY METAL-ORGANIC MOLECULAR-BEAM EPITAXY

Selective area epitaxy (SAE) of GaSb by metal-organic molecular beam epitaxy (MOMBE) on (001)GaSb substrates patterned with SiO2 films is demonstrated using triethylgallium (TEGa) and Sb4. It is found that the SAE strongly depends on the growth temperature and the flow rate of TEGa and is easily achieved at low TEGa flow rates and elevated growth temperatures. The Sb4 flux dependence is also observed. The critical growth temperature for the SAE of GaSb is lower than that of GaAs. A MOMBE selective area growth model is proposed to explain these experimental results simultaneously. The destruction of the SAE is considered to be related to the surface concentrations of group III and group V species on the SiO2 surface as well; as the bond strength between Ga and Sb (As).