SELECTIVE-AREA EPITAXY OF GAAS USING A GAN MASK IN IN-SITU PROCESSES

We performed in-situ selective-area epitaxy of GaAs using a GaN mask. The GaN mask was formed on the GaAs (100) substrate at a comparatively low temperature (610-degrees-C) by using catalytically cracked ammonia gas. After that, the GaN mask was locally exposed to an electron beam (EB) in order to make a pattern on the mask. GaAs growth was carried out on the GaN mask with the EB-exposed area by using trimethyl-gallium (TMG) and AS4 at 420-degrees-C. As a result, we confirmed from observations with a Nomarski microscope that the GaAs was selectively grown in the EB-exposed area, and that no GaAs was deposited on the GaN mask. The size of the GaAs growth area was about 6 X 12 to 7 X 23 mum2.