ABSTRACT
Abstract. Vacancy-type defects in Ga(In)NAs films grown by atomic Idassisted RF-MBE were studied by using positron annihilation technique. We found that incorporation of N into GaAs lowers the formation energy of vacancy type defects. However, despite the varying differences in the lattice misfit and N compositions for samples grown, we found no apparent differences in the S parameters. Next, the effect of atomic H irradiation on the kinetics of RF-MBE growth was investigated. Though optimized atomic H irradiation condition during growth improves the crystal quality of GalnNAs films by surfactant effect, excessive amount of atomic H tends to degrade the quality. The cracking ratio and H2 flow rate was optimized, and the surface roughness of 0.27 nm, corresponding to roughness of less than 1 ML was successfully achieved.
