Recrystallization behavior of high-dose Mn+-implanted GaAs

Raman spectroscopy was used to study the evolution of host lattice recrystallization in Mn+-implanted GaAs. A high dose of Mn+-ions (> 10(15) cm(-2)) was introduced into semi-insulating GaAs by the combinatorial implantation method. Subsequent thermal annealing at 920 degreesC was carried out to re-grow the implantation-induced amorphous layers. The dependence of the recrystallization behavior on the Mn content was systematically observed. The lattice orientation of recrystallized layers in the surface changed after high-dose implantation (> 1.6 x 10(15) cm(-2)) and annealing. The size of the recrystallized crystallites decreased with increasing Mn+ dose, as indicated by images from atomic force microscopy. The decrease in the phonon frequency-of the Raman lines with the size reduction of microcrystals was in good agreement with the spatial correlation model. However, at higher doses (> 7 x 10(16) cm(-2)), a blue shift of the frequency was observed due to the compressive stress exerted on the microcrystals.