1. Applied Physics and Semiconductor Spectroscopy, Brandenburg University of Technology Cottbus–Senftenberg, K.-Zuse-Str. 1, 03046 Cottbus, Germany
2. SENTECH Instruments GmbH, Schwarzschildstraße 2, 12489 Berlin, Germany
3. Applied Physics and Sensor Technology, Brandenburg University of Technology Cottbus–Senftenberg, K.-Wachsmann-Allee 17, 03046 Cottbus, Germany