Members of NanOp

UNIVERSITÄT WÜRZBURG, Würzburg Physikalisches Institut, Experimentelle Physik III Prof. W. Faschinger

The group is specialized on the epitaxial growth of II-VI compound semiconductors and the fabrication of optoelectronic devices. The infrastructure includes MBE machines for various II-VI compound semiconductor combinations, clean room facilities, processing lines and a rather complete set of advanced characterization techniques for a detailed analysis of optoelectronic wide gap materials and devices. II-VI based quantum dot systems have been used commercially for a long time as the basis for optical band filters. Nowadays, self-organized growth of II-VI quantum dots is being intensively investigated for the use in optoelectronic devices, covering the green and the blue spectral range (470 nm - 550 nm).

The group has pioneered the development of beryllium chalcogenides, a class of novel II-VI materials, with pronounced covalent bonding. Optoelectronic devices like laser diodes in the green spectral range as well as photodetectors are being developed. Due to the high band gap of the materials these photodetectors are superior to conventional silicon based detectors because of their large signal to noise ratio. Nanostructures are pursued by both a self-organized growth technique as well as a novel in-situ fabrication technique, making use of shadow masks during molecular beam epitaxy. Beyond the application aspects, II-VI semiconductors are an especially interesting model class of materials for the investigation of physics in reduced dimensions. Excitonic lasing has been shown to be dominating in II-VI laser structures even at room temperature and under electrical current injection. This aspect is very interesting in combination with nanostructure systems like quantum dots and quantum wires.