Growth of wurtzite‐GaN on silicon (100) substrate by molecular beam epitaxy

Abstract

We report on the growth of wurtzite-GaN layers by molecular beam epitaxy using ammonia on Si(100) substrates. We show that using 4° misoriented Si(100) substrates, GaN layers are obtained with a dominant orientation. The nucleation conditions of the AlN buffer layer as well as the entire growth process are described and compared with the process developed for the growth on Si(111) substrates, already well optimised in our laboratory [1]. The crystalline quality and polarity are assessed by transmission electron microscopy, X-ray diffraction and chemical etching. The most noticeable features of the layers grown are the high crystal quality of the AlN/Si interface, the Ga-polarity of the final GaN layer and especially the presence of the wurtzite phase only. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)