Epitaxy on GaN bulk crystals

The article shows the most important experimental results describing the properties of nitride layers on GaN single crystals. The layers were grown using metalorganic chemical vapour deposition (MOCVD). The growth was monitored by in-situ laser reflectometry. The layers contain very small dislocation density of about 10-10(3) cm-(2) (the same as in the GaN substrates). Morphology and crystallographic quality was examined using atomic force microscopy and X-ray diffraction. The layers have excellent photoluminescent properties what has a direct impact on the optoelectronic device properties.