HVPE homoepitaxy on freestanding AlN substrate with trench pattern

• Published in: Physica status solidi. C Vol. 12; no. 4-5; pp. 334 - 337
• Main Authors: Watanabe, Yoshinobu, Miyake, Hideto, Hiramatsu, Kazumasa, Iwasaki, Yosuke, Nagata, Shunro
• Format: Journal Article
• Language: English
• Published: Berlin WILEY-VCH Verlag 01.04.2015; WILEY‐VCH Verlag; Wiley Subscription Services, Inc
• Subjects: Aluminum nitride; aluminum nitride (AlN); Cross sections; Epitaxial growth; freestanding substrate; Heat treatment; homoepitaxial growth; hydride vapor phase epitaxy (HVPE); Luminescence; Polishing; Residues; Solid state physics; Sublimation; Substrates; Surface treatment; trench substrate; Trenches; Vapor phase epitaxy; Vapor phases; Vapour; Wavelengths
• ISSN: 1862-6351; 1610-1642
• DOI: 10.1002/pssc.201400202

Conditions on chemical surface treatment and thermal treatment of sublimation‐freestanding AlN substrates were investigated to remove damage layers on surfaces for high‐quality and crack‐free AlN films grown by hydride vapour phase epitaxy (HVPE). By wet etching, the residue on the surface was removed and the polishing scratches were reduced. Atomic steps were formed on the surface by the subsequent thermal treatment at 1450 °C for 10 min, and surface layer of 220 nm in thickness was removed, Homoepitaxial growth on freestanding AlN substrate with trench pattern was also performed. A crack‐free AlN film with atomic steps was obtained on the trench‐patterned bulk AlN substrate, and the emission at the band edge near 206.9 nm was dominant. The wavelength of luminescence from cross‐sectional and surface of the HVPE‐AlN layer was maintained. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)