Quantitative evaluation of silicon displacement induced by arsenic implantation using silicon isotope superlattices

We established a new method for evaluating quantitatively the silicon atomic displacement as a function of the depth from the surface induced by arsenic implantation into a silicon wafer. A simulation based on a convolution integral was developed successfully to reproduce the experimental depth profiles of isotopes in the arsenic-implanted ²⁸Si/³⁰Si isotope superlattices, from which the average distance of the silicon displacements due to the collisions with implanted arsenic is obtained. We show that it takes the average displacement of ̃0.5 nm to make the structure appear amorphous by transmission electron microscopy.