Journal of Metals, Materials and Minerals
Publication Date
2022
Abstract
Effects of Al addition on a structural phase modification in AlGaN/GaN films on GaAs substrate grown by MOVPE have been investigated. To examine the effect of Al addition, AlGaN/GaN films were grown with varied a molar flow ratio of TMAl to the total group-III elements of 0, 0.15, and 0.30. Quantity of hexagonal phase incorporation was evaluated by the ratios of integrated XRD intensity of hexagonal plane to cubic plane from reciprocal space mappings. The diffraction geometry factor was considered in the calculation. The results suggest that GaN primarily contains a hexagonal phase with a small fraction of a cubic phase (15%). With Al addition, a hexagonal phase inclusion significantly decreased. The fraction of a cubic phase becomes dominant (66%) and overcomes a hexagonal phase inclusion. As a result, with an addition of Al, our result demonstrates a structural phase modification from hexagonal to cubic phases in the AlGaN/GaN films on GaAs . Besides, TEM image and selective area diffraction patterns indicated that the structural phase might transform through stacking faults. Moreover, the area of the flat surface seen from AFM images indicated a cubic plane, therefore, can briefly comparatively predict the amount of cubic phase in the AlGaN/GaN films.
DOI
10.55713/jmmm.v32i1.1240
First Page
41
Last Page
47
Recommended Citation
Suwannaharn, Nattamon; Sanorpim, Sakuntam; Kijamnajsuk, Suphakan; Yordsri, Visittapong; Nuntawong, Noppadon; and Onabe, Kentaro
(2022)
"Effect of Al Addition on Crystal Structure of AlGaN/GaN on GaAs (001) Substrate Grown by Metalorganic Vapor Phase Epitaxy,"
Journal of Metals, Materials and Minerals: Vol. 32:
No.
1, Article 4.
DOI: 10.55713/jmmm.v32i1.1240
Available at:
https://digital.car.chula.ac.th/jmmm/vol32/iss1/4