Effect of temperature on the bulk atomic relocation in low-energy collision cascades in silicon: A molecular dynamics study

Abstract

Abstract The production of damage in a Si lattice by internally starting 100 eV self-recoils has been studied using a MD simulation. Different initial lattice temperatures below the Debye temperature for Si have been considered. The number of stable atomic displacements and the amount of atomic mixing increase with the initial target temperature. The increase with temperature of atomic mixing is nonlinear -appreciable changes take place between 300 and 500 K, while the difference between the amount of mixing corresponding to 0 and 300 K is negligibly small. The size of the cascade zone in which stable atomic displacements occur doubles itself for temperature changes between 0 and 300 K, with a value for 500 K lying in between. This nonmonotonic variation with the initial target temperature of the size of the cascade zone may have its origin in the correlation between the initial direction of motion of the starting recoil and the directions of thermal velocities of the neighbouring atoms around this recoil.