Voitovych V. The influence of isovalent lead impurity on the thermal and radiation defects creation in silicon

The influence of the doping by an isovalent Pb impurity (NPb ~ 1018 сm-3) on structural, electric, recombination parameters of n-Si, effects of irradiation as well as heat treatments are studied. The Pb-doping of Si has been revealed to result in the following: it brings the major part of the C impurity atoms out of an optically active state, and reduces the density of growth microdefects, but has no influence on the concentration of dislocations and increases the lifetime of nonequilibrium curent carriers. At the same time Pb does not create additional electrically active structural defects, while the mobility of the majority current carriers stays unchanged. The decrease of generation rate (VO - on 25%, СiСs - in 7-13 time) of main radiation defects under electron irradiation in Pb doped silicon is observed. Any lead- containing electrically active defects do not observed. Significant decrease of low temperature thermal donors generation rate in Pb doped Si is shown. Experimental results are interpreted in terms of interaction between Pb and C atoms in course of thermal and radiation defects creation.