The effect of dose of nitrogen-ion implantation on the concentration of point defects introduced into GaAs layers

Secondary-ion mass spectrometry and Rutherford proton backscattering have been used to measure the concentration profiles of nitrogen atoms and examine the defect structure of epitaxial GaAs layers implanted with 250-keV N$^{+}$ ions at doses of 5 $\cdot$ 10$^{14}$–5 $\cdot$ 10$^{16}$ cm$^{-2}$. It was found that no amorphization of the layers being implanted occurs at doses exceeding the calculated amorphization threshold, a concentration of point defects that is formed is substantially lower than the calculated value, and a characteristic specific feature of the defect concentration profiles is the high defect concentration in the surface layer.