IDENTIFICATION OF SE2 AND SE-AS PAIRS IN SILICON BY ELEMENTAL TRANSMUTATION

Selenium related levels in silicon are studied by deep level transient spectroscopy (DLTS) on the radioactive isotope Se-75. During its elemental transmutation to As-75, DLTS measurements are performed repeatedly. The two levels of the isolated Se atom are identified by their concentration decrease according to the radioactive decay law. The concentration of a level at E(c) - 0.19 eV decreases with twice the decay rate. This directly proves the involvement of two Se-75 atoms. A Se-As pair, which forms the intermediate state in the Se-2 --> (Se-As) --> As-2 transmutation, is discovered (E(2) - 0.15 eV).