Proton irradiation effects on the electric field behavior in particle detectors

The behavior of the electric field E and of the active layer width W in particle detectors are of major importance from the point of view of both the fundamental physics and the detector technological improvement. At present, it is still an open question how E and W change by irradiating the detectors with high-energy particles. This paper deals a thorough investigation on the behavior of E and W before and after irradiation carried out in silicon pin diodes as well as in gallium arsenide Schottky diodes by optical-beam-induced current (OBIC) and Surface Potential (SP) measurements. For both kinds of detectors the results are discussed relating them to the radiation-induced deep levels which have been detected by junction spectroscopy.