Controllability of β-Ga2O3 single crystal conductivity by V doping

Abstract

The introduction of different elements into semiconductors to achieve conductivity control of n-type doping has considerable scientific significance and practical application prospects, which can further promote their extensive application in the field of electronic devices. Herein, a series of V-doped beta-gallium oxide (β-Ga₂O₃) single crystals with different concentrations were cultivated using the optical floating zone method. The influence of V doping on the structural, electrical, and optical properties of β-Ga₂O₃ single crystals was systematically investigated. The characterization results revealed that V-doped β-Ga₂O₃ single crystals exhibited superior crystalline quality; moreover, the free carrier concentration increased from 6.9 × 10¹⁶ cm⁻³ to 6.4 × 10¹⁸ cm⁻³ and then decreased to 3.1 × 10¹⁶ cm⁻³ with an increase in the V concentration. The optical transmission of the crystals initially decreased in the infrared region and then increased, which is related to the change in the conductive electrons. The intensities of the two absorption peaks located at approximately 400 nm and 610 nm increased with increasing V doping concentration. From the Raman scattering spectra, the inhibition of V on the [Ga_IIO₆] octahedral peak intensity became evident with increasing V content. These valuable findings may contribute to the research on β-Ga₂O₃-based electronic and optical devices.