A trade-off relation between tilt and twist angle fluctuations in InN grown by RF-MBE

In the InN growth on sapphire substrates, it is difficult to control both of tilt and twist angle fluctuations at same time. It is necessary to understand initial growth stage such as the role of nitridation process to improve the mosaicity. Low‐temperature nitridation technique brings the drastically improvement of the tilt angle fluctuation, although the twist angle fluctuation becomes worse. Such experimental results strongly indicate that there is some trade‐off relation between the tilt and the twist angle fluctuations as a function of the nitridation condition such as the nitridation time. In this paper, we discuss about such trade‐off relation in the direct growth of InN on the nitridation sapphire substrates and also propose a simple model of initial nitridation process to explain it. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)