Influence of AlN buffer layer on growth of AlGaN by HVPE

S. Fleischmann1, E. Richter1, A. Mogilatenko1,2, M. Weyers1, G. Tränkle1

Published in:

phys. stat. sol. (b), vol. 254, no. 8, pp. 1600696 (2017).

Copyright © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


To the end of improvement of layer morphology and crystalline perfection of thick AlGaN layers grown by hydride vapor phase epitaxy (HVPE) as well as for the suppression of crystallite formation during growth, the impact of AlN buffer layer properties on AlGaN growth was investigated. While the surface morphology of 500 nm thick AlN layer improves with higher V/III ratio toward 50 and lower growth temperatures of 1020 °C, its use as a buffer layer for thick AlGaN layers leads to strong degradation of AlGaN surface and even to formation of different crystallites during growth. Best surface morphology and crystalline perfection of thick AlGaN layers was observed for the growth on an AlN buffer layer with a higher crystal quality disregarding its 3D morphology and high surface roughness. Best results were achieved at medium V/III ratio of about 10-20 and AlN buffer growth temperature of 1060 °C.

1 Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany
2 Institut für Physik, Humboldt Universität zu Berlin, Newtonstr. 15, 12489 Berlin, Germany


AlGaN, AlN, epitaxial lateral overgrowth, hydride vapor phase epitaxy, nitride semiconductors, substrates.