【Domestic Papers】 Shandong University Successfully Prepares High-Quality β-Ga₂O₃ Using Top-Seeded Solution Growth

      Researchers from the State Key Laboratory of Crystal Materials, Shandong University have published a dissertation titled " Top-seeded solution growth and characterization of β-Ga₂O₃" in CrystEngComm.

Program Support

      This study was supported by the National Natural Science Foundation of China (grant nos. 62175129), Qilu Young Scholar of Shandong University, Taishan Scholar of Shandong Province (Grant No. tsqn202306014), and Program of Introducing Talents of Disciplines to Universities in China (111 program No. BP2018013).

Abstract

      β-Ga₂O₃ is an ultra-wide bandgap semiconductor with immense potential applications in high voltage, electronic, deep-ultraviolet optoelectronic, and other devices. However, to date, the growth of bulk β-Ga₂O₃ crystals has predominantly utilized melt methods, which are heavily dependent on specific growth vessels. In this work, bulk crystal β-Ga₂O₃ with a size of 7 × 13 × 4 mm³ was grown using TeO₂–Li₂CO₃ as flux via a top-seeded solution growth (TSSG) method for the first time. It is noteworthy that the saturation point of β-Ga₂O₃ in the flux was reduced to 1023 K, which was significantly lower than its melting point of 2073 K. The resulting β-Ga₂O₃ crystal exhibited well-formed faces, predominantly the (010), (100), (01), and (1) forms, which closely align with the ideal morphological predictions made by the Bravais–Friedel and Donnay–Harker methods. The full-width at half maximum (FWHM) of rocking curves for the (010) oriented plane was determined to be 140.4′′. This work provides a potential β-Ga₂O₃ crystal growth method performed at a low temperature with little platinum loss.

Conclusions

      β-Ga₂O₃ crystals have been successfully grown using TeO₂ and Li₂CO₃ as fluxes in an enhanced top-seeded solution growth (TSSG) method. Material volatilization and platinum loss have been effectively mitigated, as the crystal growth temperature of 1273 K is below the melting point. The Laue back-reflection patterns from various sites in the (010) sample are distinct and symmetric, with a full width at half maximum (FWHM) of the rocking curve measuring 140.4″, which suggests an acceptable level of crystalline quality for the as-grown crystal.