Exploring the Feasibility of AlN/GaN HEMTs for THz Applications Using a Novel Device-Circuit Co-Design Approach

This work presents a rigorous device-circuit co-design investigation of AlN/GaN HEMT to explore its feasibility for operations at frequencies ~1 THz. A novel device-circuit co-design methodology was adopted, which involves I-V/C-V/S-parameter matching, careful extraction of a small signal model and large-signal model. This was followed by source-load pull-based power amplifier (PA) design/exploration as a function of various device design parameters. For PA operation, both class-A and class-AB operations were invested while exploring PA gain, output power, efficiency at 1dB compression point, and linearity through dual-tone (IMD3) investigations. A complete range of device design parameters are evaluated to explore the ultimate scalability limit of AlN/GaN HEMT for possible THz operation. A correlation between the device's intrinsic parameters and PA performance has also been established to uncover AlN/GaN HEMT's feasibility for ~1 THz active operation.