Growth of high-quality 1-inch diameter AlN single crystal by sublimation method

摘要

1-inch diameter AlN single crystals with the thickness of 0.025-2 mm were grown on SiC substrates by the sublimation method. Crystalline qualities were evaluated by X-ray diffraction and EPD measurements. The FWHM of X-ray rocking curve for (0002) reflection was 281 arcsec with 1.2-mm thick crystal and dislocation density measured by EPD was 1.6x10~6/cm~2 with 0.8-mm thick crystal. These results were well consistent with the dependence of those properties on the thickness of the crystal, which was found in our previous work on 10-mm diameter crystals. According to this dependence, growing the thick AlN crystal on SiC substrates by the sublimation method is expected to lead to high-quality free-standing 1-inch AlN substrates.