A Novel Method for Growing α-Ga2O3 Films Using Mist-CVD Face-to-face Heating Plates

In this paper, the method for growing alpha-Ga2O3 films on c-plane sapphire substrates using an inexpensive fine-channel mist-CVD face-to-face heating plate was investigated. Because high temperatures can result in reactor deformation, expensive AlN ceramics resistant to deformation are used as the reactor fabrication material in traditional fine-channel mist-CVD equipment, which limits its use for promotion and research purposes. In this work, we used a face-to-face heating method to replace the traditional single-sided heating method which will reduce the requirement for equipment sealability. Therefore, cheap quartz can be used to replace expensive AlN ceramics to make reactors, which can greatly reduce the cost of mist-CVD equipment. We also investigated the effects of substrate temperature and carrier gas on the crystalline quality and surface morphology of alpha-Ga2O3 films. By optimizing the fabrication conditions, we obtained triangular grains with edges that were clearly visible in atomic force microscopy images. Using absorption spectrum analysis, we also found that the optical bandgap of the film reached 5.24 eV. Finally, we recorded a value of 508 arcsec for the full width at half maximum of the alpha-Ga2O3 (0006) diffraction peak in the X-ray diffraction pattern.

Automated summary

This paper investigates the method of growing alpha-Ga2O3 films on c-plane sapphire substrates using an inexpensive fine-channel mist-CVD face-to-face heating plate. By replacing the traditional single-sided heating method with a face-to-face heating method, the requirement for equipment sealability is reduced. Additionally, by optimizing the fabrication conditions, the researchers obtained high-quality alpha-Ga2O3 films with unique surface morphology.