DAMAGE-INDUCED SURFACE EFFECTS IN SILICON DETECTORS

One of the main applications of silicon detectors in future collider e xperiments is their use in the tracking area. In addition to the very intense hadron flux (both neutral and charged) causing bulk damage, a severe effect by ionizing radiation has also to be envisioned at small radii. In the present study results obtained after irradiation with l ow energetic electrons (20 keV) are presented. In this case bulk damag e can be completely excluded. Effects on the oxide charge and density of interface states are characterized by C-V and I-V measurements. In addition the corresponding changes of the space charge region are obse rved with a scanning proton micro beam. The electric held distribution , the depletion depth and the lateral extension of the depletion regio n is thus investigated and the results are compared with detailed simu lations using the ToSCA-program.