INSITU SELECTIVE-AREA EPITAXY OF GAAS USING A GAAS OXIDE LAYER AS A MASK

Selective-area epitaxy of GaAs was performed by metalorganic molecular beam epitaxy using a GaAs oxide mask. No deposition of polycrystalline GaAs was observed on a GaAs oxide mask after the selective-area epitaxy using a trimethylgallium (TMG) and As4 as source materials. An observation of the decomposition of TMG indicated that it occurred above 350-degrees-C on an oxide-free surface of GaAs, while decomposition did not occur below 550-degrees-C on a GaAs oxide surface. This surface-catalyzed decomposition of TMG explains the selectivity of GaAs growth.