Surface passivation of GaAs by ultra-thin cubic GaN layer

Attempts were made to passivate the GaAs 001.surface by a pseudomorphic ultra-thin cubic GaN layer formed by a nitrogen radical N-radical.or nitrogen plasma irradiation technique. Reflection high-energy electron diffraction RHEED. pattern observations and detailed X-ray photoelectron spectroscopy XPS.analysis have shown that ultra-thin cubic GaN layer on GaAs 001.surface with desirable surface stoichiometry can be realized with the optimization of surface nitridation process parameters. The passivation effects, characterized by ultra-high vacuum photoluminescence UHV PL.analysis, revealed strong enhancement in band-edge PL intensity of GaAs after passivation as large as a factor of 10 when compared with the as-grown clean molecular beam epitaxy MBE.GaAs surface. q2000 Elsevier Science B.V. All rights reserved.