Two inch diameter, highly conducting bulk <b> <i>β</i> </b>-Ga2O3 single crystals grown by the Czochralski method
Zbigniew Galazka, Steffen Ganschow, Palvan Seyidov, K. Irmscher, Mike Pietsch, Ta‐Shun Chou, Saud Bin Anooz, Raimund Grueneberg, Andreas Popp, Andrea Dittmar, Albert Kwasniewski, Manuela Suendermann, Detlef Klimm, Thomas L. Straubinger, Thomas Schroeder, Matthias Bickermann
Abstract
Two inch diameter, highly conducting (Si-doped) bulk β-Ga2O3 single crystals with the cylinder length up to one inch were grown by the Czochralski method. The obtained crystals revealed high structural quality characterized by narrow x-ray rocking curves (FWHM ≤ 25 arc sec) and high surface smoothness (RMS &lt; 200 pm) of the epi-ready wafers. The free electron concentration and Hall mobility at room temperature were in the range of 1.6–9 × 1018 cm−3 and 118 – 52 cm2 V−1 s−1, respectively, which are not affected by a heat treatment at temperatures up to 1000 °C in an oxidizing atmosphere. Temperature-dependent electrical properties of the crystals revealed a degenerated semiconducting state. Both high structural quality and electrical properties make the crystals well suited as substrates for homoepitaxy and electronic device fabrication in the vertical configuration.