[TuP3B] B. RF and THz devices

[TuP3B-02] Origin of Transconductance Flattening in Graded AlGaN Channel HEMTs: Role of Mobility–Field Linearity

〇Chia-Yu Hung¹, Yuh-Renn Wu¹ (1. National Taiwan University (Taiwan))

Graded AlGaN channel high electron mobility transistors (HEMTs) have been widely reported to exhibit improved transconductance () linearity, yet the underlying physical mechanisms remain unclear. In this work, we investigate the origin of flattening by systematically examining the role of field-dependent carrier mobility. Through Monte Carlo transport and device-level simulations, we demonstrate that enhanced linearity of the mobility–electric-field (–) response is the dominant mechanism responsible for flattening in graded-channel HEMTs.