MOVPE growth of nitrogen- and aluminum-polar AlN on 4H-SiC

J. Lemettinen; H. Okumura; I. Kim; M. Rudzinski; J. Grzonka; T. Palacios; S. Suihkonen

doi:10.1016/j.jcrysgro.2018.02.020

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arXiv · 1811.03534

MOVPE growth of nitrogen- and aluminum-polar AlN on 4H-SiC

J. Lemettinen·H. Okumura·I. Kim·M. Rudzinski·J. Grzonka·T. Palacios·S. Suihkonen

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Abstract

We present a comprehensive study on metal-organic vapor phase epitaxy growth of N-polar and Al-polar AlN on 4H-SiC with 4 deg miscut using constant growth parameters. At a high temperature of 1165 degC, N-polar AlN layers had high crystalline quality whereas the Al-polar AlN surfaces had a high density of etch pits. For N-polar AlN, the V/III ratio below 1000 forms hexagonal hillocks, while the V/III ratio over 1000 yields step bunching without the hillocks. 1-um-thick N-polar AlN layer grown in optimal conditions exhibited FWHMs of 307, 330 and 337 arcsec for (002), (102) and (201) reflections, respectively.

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J. Lemettinen, H. Okumura, I. Kim, M. Rudzinski, J. Grzonka, T. Palacios, S. Suihkonen. 2018-11-08. MOVPE growth of nitrogen- and aluminum-polar AlN on 4H-SiC. https://doi.org/10.1016/j.jcrysgro.2018.02.020

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