MOLECULAR-BEAM EPITAXY REGROWTH USING A THIN IN LAYER FOR SURFACE PASSIVATION

We report a molecular beam epitaxy regrowth technique using a thin In layer for surface passivation. X-ray photoemission spectroscopy measurements show that an In layer as thin as a few tenths of an angstrom is adequate for the effective protection of the underlying III-V epilayers from carbon and oxygen contamination, while still providing exposure to the atmosphere. C-V depth profilings of the regrown pseudomorphic high electron mobility transistors (PHEMTs) reveal no significant residual charge carriers near the regrowth interface. The regrown PHEMTs with 1 μm gate length have a transconductance as high as 330 mS/mm and ft over 23 GHz.© 1995 American Institute of Physics.