A pathway to highly conducting Ge-doped AlGaN

Ge doping in AlGaN was studied over a wide dopant concentration range. For high concentrations, the formation of VIII–nGeIII determined to be main point defect limiting conductivity. It shown that complex could suppressed by controlling chemical potentials during growth, leading higher maximum achievable carrier and selective stabilization certain type. Chemical potential growth species varied changing V/III ratio temperature. Free concentrations as 4 × 1019 cm−3 were achieved Al0.4Ga0.6N:Ge grown on sapphire substrates under “metal-rich” conditions. The ability control onset self-compensation stabilize charge state compensating is great technological importance for application various devices.