Characteristics of a low-energy ion beam used for deposition

In ion beam deposition, particularly in the energy range below 100 eV, it is very important to investigate the interactions between incident ions and a surface. The high-energy neutrals included in the low-energy ion beam may influence the film formation; thus, it is necessary to detect the accurate amount of high-energy neutrals and discuss those effects. In this study, we measured the ratio of high-energy neutrals to low-energy ions using Faraday cups to eliminate ions from the ion beam, and estimated the characteristics of the ion beam. As the result, the percentage of high-energy neutrals contained in low-energy ion beam was 1.5%, and the cause of the generation of high-energy neutrals was mainly the collision between high-energy ions and inner wall of the slit.