Ion implanted AlGaN-GaN HEMTs with nonalloyed Ohmic contacts

In this letter, the incorporation of Si implantation into AlGaN-GaN high-electron mobility transistor (HEMT) processing has been demonstrated. An ultrahigh-temperature (1500°C) rapid thermal annealing technique was developed for the activation of Si dopants implanted in the source and drain. In comparison to control devices processed by conventional fabrication, the implanted device with nonalloyed ohmic contact showed comparable device performance with a contact resistance of 0.4 Ω·mm, I_max of 730 mA/mm, f_t/f_max of 26/62 GHz, and a power of 3.4 W/mm on sapphire. These early results demonstrate the feasibility of implantation incorporation into GaN-based device processing as well as the potential to increase yield, reproducibility, and reliability in AlGaN-GaN HEMTs.