High quality epitaxial AlN and Al_(x)Ga_(1-x)N layers have been grown by organo-metallic vapor-phase epitaxy on single crystal a-face AlN substrates. Here we report the characterization of these layers using Rutherford backscattering/ion channeling spectroscopy, atomic force microscopy, double crystal x-ray diffraction, and preliminary electrical results. Ion channeling along the 1120 axis gave a minimum yield of 1.5 for an AlN layer and 2.2 for an Al_(0.5)Ga_(0.5)N, indicating excellent crystal quality. A resistivity of 20 Ω cm and a mobility of 20 cm~(2)/V s was measured in a Si-doped, 1-μm-thick Al_(0.5)Ga_(0.5)N grown epitaxially on the AlN substrates.
展开▼
