Low-energy ion-beam-induced epitaxial crystallization of GaAs

Abstract

Properties of the ion-beam-induced epitaxial crystallization (IBIEC) of thin layers of amorphous GaAs with a thickness of about 110 nm formed by As ion implantation have been investigated by using low-energy Ar and Kr ions with their projected ranges within the amorphous layer thickness. Recrystallization of the amorphous layer due to bombardments of Ar ions with energies higher than 60 keV and Kr ions with those higher than 110 keV was observed to proceed up to the sample surface in a layer-by-layer growth manner with residual defects remaining in the recrystallized layer. After eliminating the sputtering effect, regrowth rates per ion fluence were observed to have pseudo-linear dependence on incident ion energy whereas regrowth rates per nuclear energy deposition density showed to vary strongly as a function of incident ion energy. Present results suggest a crucial role of defect formation and its migration in the amorphous layer in the IBIEC.