The influence of sputtering on ion implantation profiles

Abstract

The accurate knowledge of the implantation profiles is of considerable interest for testing theoretical models on the stopping of ions in matter, as well as for many important applications in metallurgy and semiconductor technology. Measurements of the depth distribution profiles of the implanted ions provide information on a wide range of fields, including ion-solid interactions, doping and diffusion. Several experimental methods have been employed to determine the depth distributions of the implanted ions. They can be divided into destructive and non-destructive methods. Most experimental results found in the literature are for heavier ions implanted into lighter target materials where the non¬destructive Rutherford Back-scattering method can be employed. Nuclear Reaction Analysis also provides a non-destructive method for determining the implanted profile of impurity atoms with mass number smaller or similar to that of the target material. One of the important effects in ion implantation is sputtering, the process in which the surface of the target material is eroded due to ion bombardment. This process modifies range moments of implantation profiles for high fluences. This study is mainly concerned about effects of sputtering on the implanted depth profile as a function of fluence and target mass. Sputtering correction factors are determined numerically to correct the theoretical depth distributions.