Research Article

Optical Properties of AlGaN/GaN HEMT Structures

Volume: 13 Number: 2 June 30, 2026

Optical Properties of AlGaN/GaN HEMT Structures

Abstract

This study investigated the optical properties of AlGaN/GaN/sapphire high-electron-mobility transistor (HEMT) structures. The AlGaN/GaN/sapphire HEMT structures were grown by metal-organic chemical vapour deposition (MOCVD). The aim of this study was to determine the optical properties, layer thicknesses, and band gap energies of the buffer layers. The Swanepoel envelope method was employed to calculate the refractive index, layer thickness, absorption coefficient, and extinction coefficient. These parameters were obtained for the transparent region as well as the weak- and medium-absorption regions. The Tauc method, together with the Kubelka–Munk method, was used to determine the optical band gap energy of the AlGaN layer.

Keywords

References

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Details

Primary Language

English

Subjects

Condensed Matter Physics (Other)

Journal Section

Research Article

Publication Date

June 30, 2026

Submission Date

April 3, 2026

Acceptance Date

June 9, 2026

Published in Issue

Year 2026 Volume: 13 Number: 2

APA
Bilgili, A. K., Baş, Y., Sarıarslan, O., Korcak, S., & Öztürk, M. K. (2026). Optical Properties of AlGaN/GaN HEMT Structures. Gazi University Journal of Science Part A: Engineering and Innovation, 13(2), 838-848. https://doi.org/10.54287/gujsa.1922780
AMA
1.Bilgili AK, Baş Y, Sarıarslan O, Korcak S, Öztürk MK. Optical Properties of AlGaN/GaN HEMT Structures. GU J Sci, Part A. 2026;13(2):838-848. doi:10.54287/gujsa.1922780
Chicago
Bilgili, Ahmet Kürşat, Yunus Baş, Orkun Sarıarslan, Sabit Korcak, and Mustafa Kemal Öztürk. 2026. “Optical Properties of AlGaN GaN HEMT Structures”. Gazi University Journal of Science Part A: Engineering and Innovation 13 (2): 838-48. https://doi.org/10.54287/gujsa.1922780.
EndNote
Bilgili AK, Baş Y, Sarıarslan O, Korcak S, Öztürk MK (June 1, 2026) Optical Properties of AlGaN/GaN HEMT Structures. Gazi University Journal of Science Part A: Engineering and Innovation 13 2 838–848.
IEEE
[1]A. K. Bilgili, Y. Baş, O. Sarıarslan, S. Korcak, and M. K. Öztürk, “Optical Properties of AlGaN/GaN HEMT Structures”, GU J Sci, Part A, vol. 13, no. 2, pp. 838–848, June 2026, doi: 10.54287/gujsa.1922780.
ISNAD
Bilgili, Ahmet Kürşat - Baş, Yunus - Sarıarslan, Orkun - Korcak, Sabit - Öztürk, Mustafa Kemal. “Optical Properties of AlGaN GaN HEMT Structures”. Gazi University Journal of Science Part A: Engineering and Innovation 13/2 (June 1, 2026): 838-848. https://doi.org/10.54287/gujsa.1922780.
JAMA
1.Bilgili AK, Baş Y, Sarıarslan O, Korcak S, Öztürk MK. Optical Properties of AlGaN/GaN HEMT Structures. GU J Sci, Part A. 2026;13:838–848.
MLA
Bilgili, Ahmet Kürşat, et al. “Optical Properties of AlGaN GaN HEMT Structures”. Gazi University Journal of Science Part A: Engineering and Innovation, vol. 13, no. 2, June 2026, pp. 838-4, doi:10.54287/gujsa.1922780.
Vancouver
1.Ahmet Kürşat Bilgili, Yunus Baş, Orkun Sarıarslan, Sabit Korcak, Mustafa Kemal Öztürk. Optical Properties of AlGaN/GaN HEMT Structures. GU J Sci, Part A. 2026 Jun. 1;13(2):838-4. doi:10.54287/gujsa.1922780