Electrical activation studies of GaN implanted with Si from low to high dose

Electrical activation studies of Si-implanted GaN grown on sapphire have been made as a function of ion dose and anneal temperature. Silicon was implanted at 200 keV with doses ranging from 1×1013 to 5×1015 cm−2 at room temperature. The samples were annealed from 1100 to 1350 °C with a 500-Å-thick AlN cap in a nitrogen environment. Samples implanted with high doses (⩾1×1015 cm−2) have optimum anneal temperatures of around 1350 °C, exhibiting a nearly 100% electrical activation efficiency, whereas low dose (⩽5×1014 cm−2) samples exhibited lower activation efficiencies, but efficiencies increase with anneal temperature even after annealing at 1350 °C.