Temperature dependent characterization of 140–180 nm AlGaN/GaN HEMTs using DC and small-signal RF measurements

B Biddut K. Sarker (KBR, Inc 1 ., Beavercreek, Ohio 45431,) N Nicholas P. Sepelak (KBR, Inc 1 ., Beavercreek, Ohio 45431,) K Karen Nishimura (KBR, Inc 1 ., Beavercreek, Ohio 45431,) D Dennis E. Walker (Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,) G Gary Hughes (Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,) I Isaac Wildeson (BAE Systems, Inc 3 ., Nashua, New Hampshire 03060,) P Puneet Srivastava (BAE Systems, Inc 3 ., Nashua, New Hampshire 03060,) B Bill Zivasatienraj K Kenneth K. Chu (BAE Systems, Inc 3 ., Nashua, New Hampshire 03060,) S Shaikh S. Ahmed (School of Electrical, Computer, and Biomedical Engineering, Southern Illinois University Carbondale 4 , Carbondale, Illinois 62901,) K Kelson D. Chabak (Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,) A Andrew J. Green (Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,) A Ahmad E. Islam (Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,)

Abstract

We conducted comprehensive direct current (DC) and small-signal radio frequency (RF) characterization on AlGaN/GaN high-electron-mobility transistors (HEMTs) from 25 to 500 °C to investigate temperature-dependent variations in key device performance metrics, such as transconductance (gm), maximum-to-minimum drain current ratio (Imax/Imin), current gain cutoff frequency (fT), maximum gain frequency (fmax), unilateral power gain, and maximum stable gain. We compared prototype 140 nm AlGaN/GaN HEMTs made with regrown Ohmic contacts with production 180 nm AlGaN/GaN HEMTs made with standard alloyed Ohmic contacts. Our findings indicate that irrespective of the type of technology, DC and RF performance parameters decline with increasing temperature. Specifically, for every 100 °C increase in temperature, fT, fmax, and gain decreased by 6–8 GHz, ∼17 GHz, and ∼1 dB, respectively. These measurements provide insights onto how these GaN-based RF devices can be used in extreme thermal environments.

Article Details

Volume / Issue Vol. 127, Issue 8
Published August 25, 2025
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (13)

B

Biddut K. Sarker

KBR, Inc 1 ., Beavercreek, Ohio 45431,

N

Nicholas P. Sepelak

KBR, Inc 1 ., Beavercreek, Ohio 45431,

K

Karen Nishimura

KBR, Inc 1 ., Beavercreek, Ohio 45431,

D

Dennis E. Walker

Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,

G

Gary Hughes

Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,

I

Isaac Wildeson

BAE Systems, Inc 3 ., Nashua, New Hampshire 03060,

P

Puneet Srivastava

BAE Systems, Inc 3 ., Nashua, New Hampshire 03060,

B

Bill Zivasatienraj

K

Kenneth K. Chu

BAE Systems, Inc 3 ., Nashua, New Hampshire 03060,

S

Shaikh S. Ahmed

School of Electrical, Computer, and Biomedical Engineering, Southern Illinois University Carbondale 4 , Carbondale, Illinois 62901,

K

Kelson D. Chabak

Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,

A

Andrew J. Green

Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,

A

Ahmad E. Islam

Air Force Research Laboratory, Sensors Directorate 2 , Wright-Patterson AFB, Dayton, Ohio 45433,