Dual-Channel SiC-AlGaN/GaN HEMT with a Drain-Connected Field Plate for Improved Breakdown Voltage and Analog/RF Performance

In this paper, a modified version of AlGaN/GaN MOS-HEMT is presented by the incorporation of dual drain-connected field-plated architecture and a dual channel to achieve an enhancement in the electrical performance of AlGaN/GaN MOS-HEMT. The performance of the device in terms of the various figures of merits including gate-source capacitance, drain current, transconductance and channel conductance, cut-off frequency, etc. has been optimized for improved breakdown voltage and Analog-RF performance. A noteworthy improvement in analog-RF characteristics is observed with a dual-field plate structure in comparison with conventional HEMT. It is also observed that dual drain-connected field plates increase the breakdown voltage while a double channel enhances the current-carrying capability of the device. The maximum cut-off frequency 285 GHz is archived for the proposed architecture. A maximum of 23.5% and 10.8% enhancement is achieved in unilateral power gain for the proposed architecture with respect to conventional and dual-field plate HEMT. Moreover, the device is further studied with different aluminium compositions to tune its electrical performance. It is found that an increase in the aluminium concentration results in 25%, 40%, 46%, and 100% improvement in drain current for every 5% increment in Al content, respectively.