50 mm diameter Sn-doped (001) β-Ga2O3 crystal growth using the vertical Bridgeman technique in ambient air

• Published in: Journal of crystal growth Vol. 546; p. 125778
• Main Authors: Hoshikawa, K., Kobayashi, T., Ohba, E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15-09-2020; Elsevier BV
• Subjects: A1. Doping; A1. X-ray topograph; A2. Bridgman technique; A2. Single crystal growth; B1. Oxides; B2. Semiconducting β-Ga2O3; Carrier density; Crucibles; Crystal defects; Crystal growth; Diameters; Dislocation density; Doped crystals; Gallium oxides; Grain boundaries; N-type semiconductors; Platinum base alloys; Resistance heating; Rhodium; Tin; X ray topography; A2. Bridgman technique; A1. Doping; B1. Oxides; B2. Semiconducting β-Ga2O3; A1. X-ray topograph; A2. Single crystal growth
• ISSN: 0022-0248; 1873-5002
• DOI: 10.1016/j.jcrysgro.2020.125778

•50 mm-diameter Sn-doped (001) β-Ga2O3 crystals were grown in the VB furnace with ambient air.•Dislocation densities was widely distributed across a wafer from 100 to 2000/cm2.•FWHM values was also widely distributed across a wafer from 10 to 50 arcsec.•A carrier density of 3.6 × 1018/cm3 were obtained from a 0.1 mol% Sn-doped crystal.•The obtained (001) n-type wafers might be useful for epitaxial growth substrate.
50 mm-diameter Sn-doped β-Ga2O3 crystals with growth orientation perpendicular to (001) plane were grown with the newly-developed resistance heating vertical Bridgeman furnace using platinum–rhodium alloy crucibles in ambient air. Weak low angle grain boundaries and several small grains were detected on the both-side mirror-polished 50 mm-diameter (001) wafer, using high resolution refraction x-ray topography. However, no imperfections were observed over the whole wafer area when using crossed polarizer analysis. Measured values of both the full width at half maximum and the dislocation densities were widely distributed in the wafer, ranging from 10 to 50 arcsec and 100 to 2000 /cm2 respectively with no distinctive correlations among them. The Sn-doped crystals with concentrations ranging from 5 × 1017 to 5 × 1018 atom/cm3 could be grown by Sn-doping in a range from 0.05 to 0.1 mol%, and (001) oriented, 50 mm-diameter n-type oxide semiconductor wafers with a carrier density of 3.6 × 1018 /cm3, a mobility of 60 cm2/Vsec and a resistivity of 0.03 Ω-cm, were obtained from a 0.1 mol% Sn-doped crystal.