Growth process, defects, and dopants of bulk β-Ga2O3 semiconductor single crystals

β-gallium oxide (β-Ga2O3), as the typical representative of the fourth generation of semiconductors, has attracted increasing attention owing to its ultra-wide bandgap, superior optical properties, and excellent tolerance to high temperature and radiation. Compared to the single crystals of other semiconductors, high-quality and large-size β-Ga2O3 single crystals can be grown with low-cost melting methods, making them highly competitive. In this review, the growth process, defects, and dopants of β-Ga2O3 are primarily discussed. Firstly, the growth process (e.g., decomposition, crucible corrosion, spiral growth, and development) of β-Ga2O3 single crystals are summarized and compared in detail. Then, the defects of β-Ga2O3 single crystals and the influence of defects on Schottky barrier diode (SBD) devices are emphatically discussed. Besides, the influences of impurities and intrinsic defects on the electronic and optical properties of β-Ga2O3 are also briefly discussed. Concluding this comprehensive analysis, the article offers a concise summary of the current state, challenges and prospects of β-Ga2O3 single crystals.