r---r--.--.....----.--.--..---

Figure 1. Room-temperature sheet electron concentrations (a) and Hall mobilities (b) forGaN implanted at 25 and 800 °C with 200 keV Si ions at doses ranging from 5xl014 to 5xl015 cm-2 and annealed at 1050 to 1350 °C from 5 min to 17 s.