[MoB3] Crystal Growth & Characterization of Oxides

2:00 PM - 2:30 PM JST(5:00 AM - 5:30 AM UTC)

[MoB3-01 Invited] Bulk rutile-GeO₂ single crystals, epi-ready wafers, and physical properties – a comparison with beta-Ga₂O₃ and beta-(Al_xGa_1-x)₂O₃ single crystals.

〇Zbigniew Galazka¹, Andreas Fiedler¹, Saud Bin Anooz¹, Albert Kwasniewski¹, Uta Juda¹, Roberts Blukis¹, Tobias Schulz¹, Martin Albrecht¹, Steffen Ganschow¹, Thomas Schroeder^1,2, Matthias Bickermann^1,3 (1. Leibniz-Institut für Kristallzüchtung (IKZ) (Germany), 2. Humboldt-Universität zu Berlin, Institut für Physik (Germany), 3. Technische Universität Berlin, Institut für Chemie (Germany))

Bulk rutile-GeO₂ (r-GeO₂) single crystals were grown by the Top-Seeded Solution Growth (TSSG) method. From the crystals of 10-18 mm diameter differently oriented epi-ready wafers of 5x5 and 10x10 mm² were prepared. The FWHM of the rocking curves was 13-26 arcsec, while the RMS roughness 100-150 pm, with further improvement to 70 pm after annealing. The crystals were undoped and doped with Sb⁵⁺, Al³⁺, and Ga³⁺. They were studied structurally, thermally, optically, and electrically. Sb⁵⁺ is a very effective shallow donor outputting electron conc. (n_e) of 2x10²⁰ cm^-3, well suited for power devices in the vertical architecture. The obtained r-GeO₂ crystals and their properties are compared with those of beta-Ga₂O₃ and beta-(Al_xGa_1-x)₂O₃ single crystals grown by the Czochralski method.