Ion Implantation in Metals

Abstract

The purpose of this chapter is to give an overview of ion implantation in metals. This field has expanded into many areas; however, most of the work may be categorized into one of two areas. The first, and the major emphasis of this chapter, is the use of ion implantation to modify the properties of materials. This use of implantation is proving to be a valuable tool in developing our understanding of the microscopic basis of materials' properties. In addition, there is the potential of tailoring surface properties of metal components for specialized applications. The second major area is the use of ion implantation as a general research tool. This controlled introduction of elements and defects provides a method to explore kinetics and equilibria in metal alloying reactions, to investigate the formation of new phases, and to simulate radiation effects relevant to nuclear reactor environments. Current uses of ion implantation extend from research laboratory studies of metastable phase formation to production line fabrication of integrated circuits. This widespread application of ion implantation stems from several advantages' of the process. The number of ions implanted can be controlled by counting the charge each ion brings to the surface. In addition the penetration depth can be independently controlled by varying the energy of the incident beam. Thus the composition as a function of depth can be tailored over a wide range. Finally, pure beams of any atomic number can be implanted into almost any solid, opening an almost endless range of material combinations that can be explored. These advantages lead to extreme control and versatility of the process. There are a number of special features of ion-implanted materials. First,