A comparative study was made on the radiation damage caused by fast-pile neutrons in n-Si with low and high concentrations of O by measuring the effective carrier concentrations and energies of defects. The role of clusters in degrading Si parameters was studied both experimentally and theoretically. It was shown experimentally that the fluence for which the carrier concentration tends to the intrinsic value did not depend on the oxygen concentration. The theoretical calculation was carried out in the framework of Gossick’s corrected model. The additional overlapping of clusters due to introduce of defects was explained. The model of the n→p conversion in n-Si with various oxygen concentrations was presented. It was shown that divacancy and di-interstitial congestions

were responsible for the Fermi level position near the mid-gap at high fluences. Analysis of Vξ defect levels gave evidences of increase of level energy in the forbidden band on capture of the first or the second electron on the value ΔE = 0.33/ξ, where was between 1 and 5.

Particularities of the Formation of Radiation Defects in Silicon with Low and High Concentrations of Oxygen. A.P.Dolgolenko, P.G.Litovchenko, M.D.Varentsov, G.P.Gaidar, A.P.Litovchenko: Physica Status Solidi B, 2006, 243[8], 1842-52