Ultra-low resistive ohmic contacts on n-GaN using Si implantation

Implanted ohmic contacts were made on molecular beam epitaxy grown GaN materials. Si was implanted at a doping density of about 4×1020 cm-3 to decrease the contact resistance of the contact, followed by an activation anneal at 1150 °C for 30 s. The overlay metal Ti/Au was evaporated. Four-probe measurements were performed on transmission line model patterns. The measured maximum contact resistance was 0.097 Ω mm and the apparent specific contact resistance was 3.6×10−8 Ω cm2.