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Alloyed and symmetrical n+Â¿n+ devices made of nominally 75kÂ¿cm Â¿-type Si are analyzed before and after irradiation with 14MeV neutrons at room temperature and doses of 1.2Ã1011, 5.5Ã1011 and 4.0Ã1012n/cm2. Immediately after the application of a large turn-on voltage step at t Â¿ O, the flow of electrons through these devices is by pure, trap free, space-charge-limited current (sclc). From an analysis of this sclc, it is established that the drift velocity-field relationship of electrons in Si is affected by the radiation only at low temperatures in the low field range. For t>0, the current after irradiation decays below its initial trap free sclc value, thus revealing the presence of traps. Two categories are identified: fast traps with energy levels at about Â¿Etf Â¿ 0.13eV below the conduction band and slow traps with energy levels at roughly Â¿EtsÂ¿005eV. Cross sections are also obtained. Introduction rates are about equal for both (llcm-l for fast traps and 8cm-1 for slow traps). These results demonstrate the sensitivity of sclc as a tool to detect traps and changes in the drift velocityfield relationship caused by radiation. Some implications of these results are discussed and additional experiments are suggested.