High mobility quaternary AlGaScN/GaN heterostructures grown by metalorganic chemical vapor deposition

V V. R. Muthuraj (Materials Department, University of California 1 , Santa Barbara, California 93106,) C C. E. Vozel (Materials Department, University of California 1 , Santa Barbara, California 93106,) M M. Kim F F. Wu C C. J. Clymore (Electrical and Computer Engineering Department, University of California 3 , Santa Barbara, California 93106,) A A. Almogbel (King Abdulaziz City for Science and Technology (KACST) 4 , Riyadh,) S S. Nakamura (Materials Department, University of California 1 , Santa Barbara, California 93106,) J J. S. Speck (Materials Department, University of California 1 , Santa Barbara, California 93106,) U U. K. Mishra (Electrical and Computer Engineering Department, University of California 3 , Santa Barbara, California 93106,) S S. Keller S S. P. DenBaars (Materials Department, University of California 1 , Santa Barbara, California 93106,)

Abstract

Quaternary AlGaScN may mitigate ongoing growth challenges with metalorganic chemical vapor deposition (MOCVD)-grown AlScN, namely, compositional inhomogeneities, interface quality, and high impurity levels. However, there are very few reports on epitaxial AlGaScN with no MOCVD data. In this work, MOCVD growth experiments of AlGaScN/GaN high electron mobility transistor (HEMT) structures were performed. AlGaScN/GaN samples demonstrated abrupt interfaces and smooth surfaces. The quaternary barrier structures consistently exhibited high mobilities and low sheet resistances compared to equivalent ternary AlScN-based structures. Electron mobilities of up to 1731 cm2 V−1 s−1 were achieved at a sheet charge of 1.7 × 1013 cm−2, with a sheet resistance of 212 Ω/□. These results indicate significant potential for AlGaScN barrier HEMTs grown by MOCVD.

Article Details

Volume / Issue Vol. 128, Issue 11
Published March 16, 2026
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (11)

V

V. R. Muthuraj

Materials Department, University of California 1 , Santa Barbara, California 93106,

C

C. E. Vozel

Materials Department, University of California 1 , Santa Barbara, California 93106,

M

M. Kim

F

F. Wu

C

C. J. Clymore

Electrical and Computer Engineering Department, University of California 3 , Santa Barbara, California 93106,

A

A. Almogbel

King Abdulaziz City for Science and Technology (KACST) 4 , Riyadh,

S

S. Nakamura

Materials Department, University of California 1 , Santa Barbara, California 93106,

J

J. S. Speck

Materials Department, University of California 1 , Santa Barbara, California 93106,

U

U. K. Mishra

Electrical and Computer Engineering Department, University of California 3 , Santa Barbara, California 93106,

S

S. Keller

S

S. P. DenBaars

Materials Department, University of California 1 , Santa Barbara, California 93106,