Solid-phase epitaxy induced by low-power pulsed-laser annealing of III-V compound semiconductors.

Abstract

Low-power pulsed-laser annealing (LPPLA) was applied to III-V compound semiconductors GaAs and InP. The effects have been analyzed using several experimental techniques such as reflection high-energy electron diffraction, Rutherford backscattering spectroscopy, x-ray photoelectron spectroscopy, and electrical measurements. In addition, a calculation method was developed to study the heat propagation in the irradiated sample during the LPPLA process. The irradiation conditions, realizing a uniform surface laser-energy distribution, made possible a unidimensional approach. The results obtained experimentally and by numerical modeling agree well if one assumes that a solid-phase epitaxy takes place. The XPS measurements for GaAs and InP show, in particular, that a range of the irradiation power density exists where the LPPLA can effectively restore the lattice order without appreciable alteration of the surface stoichiometry. At higher power density of irradiation, the As and P vacancies introduced by the laser, in GaAs and InP, respectively, may no longer be neglected. \textcopyright{} 1996 The American Physical Society.