Mapping Analysis of Crystalline Perfection and UV-C Transparency of 2-in. Aluminum Nitride Substrates Grown by Physical Vapor Transport

Large-diameter, single-crystalline aluminum nitride (AlN) substrates are sought for growth of AlGaN-based devices. A combination of high crystalline perfection and optical transparency is desired for UV-C emitter applications. A mapping analysis of 2-in. AlN substrates grown by physical vapor transport is performed to study the within-wafer uniformity of structural and optical properties. Substrates with spatially uniform crystalline perfection and UV-C absorption coefficients, as determined by typical X-ray rocking curve widths below 15 arcsec and 4.68 eV absorption coefficients below 20 cm-1, are shown. These findings demonstrate a robust mass production process for high-quality, 2 in. AlN substrates possessing uniform structural and UV optical properties, making them highly suited for growth of next-generation, AlGaN-based devices. A study of aluminum nitride (AlN) crystals grown by high-temperature vapor transport, using a combination of structural and optical characterization techniques, is performed. The findings demonstrate a robust production process for high-quality, 2-in. AlN substrates with uniform structural and optical properties. These substrates are desirable for growth of next-generation, ultrawide-bandgap electronic and optoelectronic devices.image (c) 2023 WILEY-VCH GmbH