  This work focuses on the investigation of radiation induced defects
responsible for the degradation of silicon detectors. Comparative studies of
the defects induced by irradiation with 60Co- rays, 6 and 15 MeV electrons, 23
GeV protons and 1 MeV equivalent reactor neutrons revealed the existence of
point defects and cluster related centers having a strong impact on damage
properties of Si diodes. The detailed relation between the microscopic reasons
as based on defect analysis and their macroscopic consequences for detector
performance are presented. In particular, it is shown that the changes in the
Si device properties after exposure to high levels of 60Co- doses can be
completely understood by the formation of two point defects, both depending
strongly on the Oxygen concentration in the silicon bulk. Specific for hadron
irradiation are the annealing effects which decrease resp. increase the
originally observed damage effects as seen by the changes of the depletion
voltage. A group of three cluster related defects, revealed as deep hole traps,
proved to be responsible specifically for the reverse annealing. Their
formation is not affected by the Oxygen content or Si growth procedure
suggesting that they are complexes of multi-vacancies located inside extended
disordered regions.
