3D Simulations for Fin Geometry Effects on the Linearity and On-Resistance of AlGaN/GaN Multi-Channel Fin-HEMTs

In this work, the effects of fin geometry on the linearity and on-resistance (Ron) of AlGaN/GaN multi-channel Fin-HEMTs are systematically investigated using three-dimensional technology computer aided design (3D TCAD) simulations. Compared with baseline planar HEMTs (BSL HEMTs), the multichannel Fin-HEMTs exhibit significantly improved linearity and conduction performance. The simulation results further reveal distinct trends in multi-channel Fin-HEMTs characteristics associated with variable fin geometry. Specifically, a larger fin length increases the carrier path leading to increased Ronand degraded linearity. In contrast, narrower fins leads to higher Ronand better linearity, which is attributed to the stronger channel confinement. Alternatively, increasing fin height reduces Ronand better linearity. Finally, the duty ratio (α) strongly influences inter-fin coupling. These findings provide valuable physical insights and practical design guidelines for optimizing the design of GaN-based multi-channel Fin-HEMTs.