| Abstract: | This paper concerns with integrated microscopic investigations of bipolar junction damages in silicon detectors following neutron irradiation. This phenomenon was studied by means of an advanced contact potential difference method in atomic force microscopy (AFM). The obtained results were confirmed by topographical investigations also done by AFM and electron beam induced current, installed on a conventional scanning electron microscope. The most detailed structural investigations were carried out by means of scanning tunnel microscope. It was found that in the interval of neutron fluences, Φ,9.9×1010Φ3.12×1015 n/cm2 the damage to the silicon lattice structure is accumulative, from small point defects to high defect accumulations. These defects consisted of large complexes of dislocation loops and vacancies, however, in the p–n junction region, only vacancies remained. This deterioration in the junction crystalline structure, resulted in a population inversion of the free charge carriers, from n- to p-type. The novelty of this research consists of the direct correlation, found between the structural defects and the mechanical and electrical properties of the diode junction. |
