The model of nucleation of vacancy clusters in the cascade range in the stage of the thermal spike

Abstract
The calculation model of nucleation of large vacancy clusters in the cascade damage zone formed by means of some mechanisms of spatial vacancy rearrangements in the cooling stage of the energetic cascades has been proposed. Using the Monte-Carlo method, the model describes the clustering of monovacancies, divacancies and larger vacancy clusters migrating in the nonhomogeneous temperature field of the thermal spike (TS). An anisotropic character of the defect jumps resulted from temperature gradients in the TS has been considered. The model involves the possibility of the defect rearrangements due to melting and recrystallization of the depleted zone. In terms of the model the nucleation of vacancy clusters in the isolated cascade region of the 30-keV cascade in copper has been investigated and the size distribution of clusters has been obtained.