AlN capped annealing of Si implanted semi-insulating GaAs

AlN capped annealing can be used successfully for thin n-layer formation to minimize the thermal conversion effects. Si ions were implanted into Cr-doped semi-insulating GaAs substrates with 145 keV, to a dose of 2.40×1012 cm−2. Subsequently, the samples were annealed at 850 °C, 20 min with reactive sputtered AlN cap. The carrier profiles fit very well to the theoretical one. No thermal pits, cracks, and peeling-off were observed even on 1.2-μm-thick AlN cap after up to 1000 °C annealing.