Enhancing High-Frequency Performance of Millimeter-Wave Transistors by Optimizing Device Width

The high-frequency operability of millimeter-wave devices is investigated in this paper. An AlGaN/GaN HEMT device is studied, and the results obtained from the distributed modeling approach is compared with measurements. To validate the performance of the modeling approach, non-linear operation of the model under large signal analysis is demonstrated. According to the distributed model, the signal behavior on the input and output electrodes are observed for various operating frequencies. The main reasons for the discrepancies in the output power and gain of the device are explained and the limitations arisen from the device width in higher frequency bands can be exploited. Finally, a solution is provided to demonstrate alleviating the frequency restrictions and nonlinear frequency-gain relations for devices configured with the current fabrication technologies.