Dataset: Growth of hexagonal BN crystals by traveling-solvent floating zone

Full raw dataset for https://doi.org/10.1016/j.jcrysgro.2025.128164 supporting growth of large, high-purity single-crystals of hexagonal BN (h-BN). This includes demonstration via X-ray tomography, X-ray diffraction and scanning electron microscopy that h-BN crystals can be grown by traveling-solvent floating-zone (TSFZ). The diameters of grown boules range from 3 – 5 mm with lengths from 2 – 10 mm. Tomography indicates variable grain sizes within the boules, with the largest having areas of
1 mm
2 mm and thickness
0.5 mm. Although the boules contain macroscale flux inclusions, the h-BN lattice itself is of high quality for samples grown under optimized conditions. The currently optimized growth procedure employs an Fe flux, moderate N
pressure (
6 bar), and a growth rate of 0.1 mm/h. Raman spectroscopy for an optimized sample gives an average linewidth of 7.7(2) cm−1 for the E
intralayer mode at 1365.46(4) cm−1 and 1.0(1) cm−1 for the E
interlayer shear mode at 51.78(9) cm−1. The corresponding photoluminescence spectrum shows sharp phonon-assisted free exciton peaks and minimal signal in the energy range corresponding to carbon-related defects (
= 3.9 – 4.1 eV). The data demonstrates the viability of growing h-BN by the TSFZ technique, thereby opening a new route towards larger, high-quality crystals and advancing the state of h-BN related research.