Accurate Modeling of GaN HEMT RF Behavior Using an Effective Trapping Potential
Journal article, 2018

This paper investigates the back-gating effects due to traps, and presents a new nonlinear trap modeling approach suitable for gallium nitride (GaN) high electron mobility transistors (HEMTs). It is shown that the traps have nonidentical influence on the channel compared with the gate. The potential due to trapped electrons in the buffer and the gate-source voltage need to be differentiated to model their respective influence on conductivity of the 2-D electron gas. Hence, the back-gating potential due to traps cannot be included in the transistor model by directly offsetting the gate-source voltage. A new modulation factor is therefore introduced to create an effective back-gating potential, and thereby improve the modeling of trapping effects. The proposed nonlinear trap model is shown to accurately predict the trapping behavior for a large voltage operating region. A detailed procedure is presented to derive the model parameters from basic device measurements. The model is experimentally validated and shown to accurately predict dc-, pulsed-IV, and large-signal waveform performance for a commercial GaN HEMT.

Buffer traps

large-signal model

high electron mobility transistor (HEMT)

nonlinear model

symmetrical model

FET

small-signal model

gallium nitride (GaN)

trap model

dispersive effect

trapping

trap

Author

Ankur Prasad

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Mattias Thorsell

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

GigaHertz Centre

Herbert Zirath

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

Christian Fager

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

GigaHertz Centre

IEEE Transactions on Microwave Theory and Techniques

0018-9480 (ISSN) 15579670 (eISSN)

Vol. 66 2 845-857 8046151

Areas of Advance

Information and Communication Technology

Infrastructure

Kollberg Laboratory

Subject Categories

Applied Mechanics

Other Physics Topics

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1109/TMTT.2017.2748950

More information

Latest update

4/5/2022 7