Effects of Electrodes Layout on Performance of Millimeter-Wave Transistors

This work presents a systematic parameter extraction methodology for modeling of millimeter-wave transistors. The physics-based parameter extraction approach in this study is included in the wave-electron-transport model to improve the accuracy of the simulation results. The effects of extrinsic parameters on the performance of the device are also analyzed in detail. Skin effects and sharp metallization edge effects as the two physical phenomena that impact the current distribution and the resistance of millimeter-wave transistors are studied thoroughly. Two common electrode layout variations, the T configuration and the fork configuration, are compared. The comparison mainly targeted their performance on upper millimeter bands where physical phenomena like wave-propagation effects are dominant. The output power and the power gain of the transistor for a GaN-HEMT device are simulated and compared with measurements. Results illustrate the influence of parameters and electrode layout design on the accuracy of the modeling approach.