Inductively coupled plasma-induced etch damage of GaN p-n junctions

Plasma-induced etch damage can degrade the electrical and optical performance of III-V nitride electronic and photonic devices. We have investigated the etch-induced damage of an inductively coupled plasma (ICP) etch system on the electrical performance of mesa-isolated GaN pn-junction diodes. GaN positive-insulating-negative mesa diodes were formed by Cl-2/BCl3/Ar ICP etching under different plasma conditions. The reverse leakage current in the mesa diodes showed a strong relationship to chamber pressure, ion energy, and plasma flux. Plasma induced damage was minimized at moderate flux conditions (less than or equal to 500 W), pressures greater than or equal to 2 mTorr, and at ion energies below approximately -275 V. (C) 2000 American Vacuum Society. [S0734-2101(00)00304-3].