In order to improve the accuracy of detector-based radiometry in the UV
several types of photodiode shall be probed for their suitability as radiometric standards Initially the focus will be on a newly developed type of Schottky-barrier silicon photcdiode (PtSi-n-Si), which, according to first investigations by PTB is virtually stable in the entire UV spectral range. Exploiting the different research capabilities at the participating laboratories, the aim of the collaboration is the complete characterization of the electrical and optical properties of the new PtSi-n-Si photodiodes in comparison to other types of photodiode under different operation condition (e g. using different radiation sources - lasers, incancescent lamps, synchrotron radiation). As PTB shall provide the PtSi-n-Si diodes and calibrate them initially, an indirect comparison of UV spectral responsivity scale will be a by-product of the collaboration.
Progress report submitted in May 2004. Collaboration includes non-Euromet partners NIST (USA).