Fabrication and characterization of transparent conductive Sn-doped β-Ga2O3 single crystal

Transparent conductive Sn-doped beta-Ga2O3 single crystal with high crystallinity was successfully fabricated as a substrate for the growth of GaN-based compounds. Sn-doped beta-Ga2O3 single crystals were grown using a floating zone (FZ) method, and the properties of electrical conductivity, optical transmittance, and crystallinity were characterized to optimize the growth condition. It was found that these properties are controlled by the Sn doping concentration, and the specimen for 32 ppm Sn-doped beta-Ga2O3 single crystal was optimized to satisfy these properties simultaneously, i.e. the substrate with the internal optical transmittance of above similar to 85 % in the visible region, the electrical resistivity of 4.27x10(-2) Omega cm, the carrier density of 2.26x 10(18) cm(-3), and the FWMM of X-ray rocking curve of 43 arcsec was obtained. (c) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.