【Substrate Papers】Effect of Oxygen Partial Pressure on β-Ga₂O₃ Single Crystals Grown by Optical Floating Zone Method

      Researchers from Nanjing University of Posts and Telecommunications and Shanghai Institute of Optics and Fine Mechanics have published a dissertation titled " Effect of Oxygen Partial Pressure on β-Ga₂O₃ Single Crystals Grown by Optical Floating Zone Method " in Journal of Synthetic Crystals.

Abstract

      Gallium oxide (Ga₂O₃) is a representative fourth-generation semiconductor with unique physical properties and the advantage of readily available large-area single crystals. These characteristics make Ga₂O₃ highly attractive for deep-ultraviolet photodetection and high-efficiency power electronic applications. Oxygen vacancies are among the most common intrinsic point defects in oxide semiconductors and play a crucial role in determining the material quality and device performance of Ga₂O₃. Therefore, effective control of oxygen vacancies in Ga₂O₃ single crystals is of significant practical importance. In this work, β-Ga₂O₃ single crystals were grown by the optical floating zone method, which enables crucible-free growth and high material purity. A precisely controlled Ar/O₂ mixed atmosphere was employed to systematically investigate the effect of oxygen partial pressure on oxygen vacancy defects in β-Ga₂O₃ single crystals. With increasing oxygen content in the growth atmosphere, the optical transmittance of the crystals is markedly enhanced, and the lattice ordering is significantly improved. Meanwhile, the defect-related photoluminescence emission is strongly suppressed. X-ray photoelectron spectroscopy analyses of the O 1s anion and Ga 3d cation states consistently demonstrate that the concentration of oxygen vacancies decreases with increasing oxygen partial pressure. These results indicate that oxygen partial pressure is an effective parameter for regulating oxygen vacancy defects in β-Ga₂O₃ single crystals. This study provides practical guidance for the growth of high-quality oxide semiconductor single crystals.

LINK：

https://kns.cnki.net/kcms2/article/abstract?v=8kKd7LBMH3zU0h8c6odKfWvmPQjMQFmy5iXLkYiSX7On-8V5y-3xGGCt0hMsLMFDiH0aUJjEfA3_IVk0okCaeg3Vu41pFNgDRXLmQQ0oc-5YSWzFzC4mLYLrEDdE5MxlKZ8uiU_iYLR0d8jIFyl5wJmnKMjTSDye_MS9fF43_O1HhHgZ-8i5hA==&uniplatform=NZKPT&language=CHS