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Issue
Vol. 35 No. 4 (2025): JST: Engineering and Technology for Sustainable Development (10/2025)
Section
Research article
How to Cite
Nguyen Le, M. A., Do, D. M., Nguyen, D. H., Pham, M. K., Nguyen, H. H., Hoang, T. N. Q., Dao, H. B., & Ha, M. T. First-Principles Study on the Electronic Structure and Optical Properties of α-(AlxGa1-x)2O3 Alloys. Engineering and Technology For Sustainable Development, 35(4), 009-016. Retrieved September 30, 2025, from https://jst.vn/index.php/etsd/article/view/1064

First-Principles Study on the Electronic Structure and Optical Properties of α-(AlxGa1-x)2O3 Alloys

Manh An Nguyen Le1, Dang Minh Do1, Duc Hoang Nguyen1, Mai Khanh Pham1, Hong Hai Nguyen1, Thi Ngoc Quyen Hoang1, Hong Bach Dao1, Minh Tan Ha1,
1 School of Materials Science and Engineering, Hanoi University of Science and Technology, Ha Noi, Vietnam

Main Article Content

Abstract

The study focuses on exploring the exceptional electronic and optical properties of the α-(AlxGa1-x)2O3 alloys (AlGaO) using advanced density functional theory (DFT) with hybrid functional methods. By varying the Al content (x) from 0 to 1, the bandgap expands from 5.288 eV to 8.819 eV while maintaining its direct nature. The incorporation of Al significantly enhances the material’s ability to absorb high-energy ultraviolet light, particularly in the deep ultraviolet region (wavelength < 200 nm), due to the strong covalent nature of Al-O bonds and the widened conduction band. The absorption spectra exhibit a distinct shift toward higher energies as the Al ratio increases, accompanied by pronounced optical anisotropy along the x and z crystallographic directions. These characteristics highlight the alloy’s flexible tunability, making it an ideal candidate for advanced applications such as ultraviolet band-C (UVC) sensors, germicidal light sources, and anti-reflective coatings. This study not only provides a solid theoretical foundation for optimizing α-(AlxGa1-x)2O3 as a versatile wide-bandgap semiconductor but also paves the way for future experimental studies to fully unlock its potential in next-generation electronic and optoelectronic devices.

Keywords

AlGaO alloys, density functional theory, electronic structure, ultra-wide bandgap semiconductors, UVC absorption

Article Details

References

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