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Journals / Gazi University Journal of Science Part A: Engineering and Innovation / 2026 / Volume: 13 Issue: 2

Optical Properties of AlGaN/GaN HEMT Structures

Ahmet Kürşat Bilgili(GAZİ ÜNİVERSİTESİ)0000-0003-3420-4936
Yunus Baş(GAZI UNIVERSITY)0009-0000-5043-3873
Orkun Sarıarslan(GAZI UNIVERSITY)0009-0003-9852-5752
Sabit Korcak(ARTVİN ÇORUH ÜNİVERSİTESİ)0000-0003-1140-6391
Mustafa Kemal Öztürk(GAZI UNIVERSITY)0000-0002-8508-5714
Pages
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Publication Date
2026-06-30
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

The Tauc method, together with the Kubelka–Munk method, was used to determine the optical band gap energy of the AlGaN layer.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:This study investigated the optical properties of AlGaN/GaN/sapphire high-electron-mobility transistor (HEMT) structures.
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Key Findings & Data:The AlGaN/GaN/sapphire HEMT structures were grown by metal-organic chemical vapour deposition (MOCVD).
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Conclusion & Impact:The Tauc method, together with the Kubelka–Munk method, was used to determine the optical band gap energy of the AlGaN layer.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:HEMT · AlGaN · MOCVD

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.

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Cite This Article

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, Volume: 13 Issue: 2. https://doi.org/10.54287/gujsa.1922780

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