Author(s): Wu, SH (Wu, Songhao); Ma, CC (Ma, Chicheng); Yang, H (Yang, Han); Liu, ZC (Liu, Zichun); Ma, YX (Ma, Yuanxiao); Yao, R (Yao, Ran); Zhang, YY (Zhang, Yiyun); Yang, H (Yang, Hua); Yi, XY (Yi, Xiaoyan); Wang, JX (Wang, Junxi); Wang, YL (Wang, Yeliang)

Source: CRYSTENGCOMM DOI: 10.1039/d4ce00263f  Early Access Date: APR 2024  Published Date: 2024 APR 11 

Abstract: High-quality beta-(AlxGa1-x)(2)O-3 thin films are fabricated through face-to-face annealing on sapphire substrates covered with epitaxial Ga2O3. Al atoms during high-temperature annealing are uniformly diffused from the sapphire substrate into the overlying Ga2O3 for (AlxGa1-x)(2)O-3 formation. The transformation of the (-201) crystal facet into the (300) crystal facet is observed, which is likely due to the lowest E-surf((hkl)) of the (100) surface. The crystallinity can be further improved with increasing the annealing temperatures and the duration of the thermal treatment under a tolerance limit of 1400 degrees C, which also increases the Al content to 0.68 in beta-(AlxGa1-x)(2)O-3 with a bandgap of up to 6.0 eV. As a result, highly-crystalline (300)-plane beta-(AlxGa1-x)(2)O-3 is obtained with a low X-ray diffraction (XRD) full width at half maximum (FWHM) at around 0.08 degrees (288 arcsec). These findings contribute to the understanding of the preparation of high-quality beta-(AlxGa1-x)(2)O-3 films on sapphire substrates.

Accession Number: WOS:001207840100001

eISSN: 1466-8033