Citation
Thonke, K.; Neuschl, B.; Feneberg, M.; Collazo, R.; Sitar, Z.; Yang, Z.; Wunderer, T. Optical studies on homoepitaxial AlN. EXMATEC – 11th Expert Evaluation & Control of Compound Semiconductor Materials & Technologies; 2012 May 30 – June 1; Porquerolles, France.
Abstract
Recently, AlN bulk crystals with very high crystal quality have become available in diameters up to 25 mm. Metal-organic vapor phase epitaxy (MOVPE) allows to grow either very pure homoepitaxial AlN layers, or layers with controlled silicon (n-type) doping. We investigated such layers by low-temperature photoluminescence (PL), reflectance, and ellipsometry. We find very narrow lines, which allow a clear identification of the spectral features related to different free and bound exciton states, and to the multiple valence bands.
