HISTORICAL-PERSPECTIVE OF MEAL IMPLANTATION

The process of ion implantation was introduced about 30 years ago for the doping of silicon crystals. A few years later, around 1970, there began the first systematic investigations of the modification of metals and alloys in order to improve their resistance to wear and corrosion. It was shown to be possible to take advantage of the low temperature, non-equilibrium nature of the process and to exceed normal solubility limits. Some of the research programs exploited the versatility of ion implantation in order to prepare specimens for comparative studies of their oxidation or corrosion behavior, thus using it as a valuable research tool. By 1975, it was possible to initiate a program aimed at the industrial application of a non-analyzed beam of nitrogen ions, and the first implanter designed to this purpose was constructed in 1976. Progress to a much larger (2.6 m) facility took place in 1985, and it became possible to demonstrate the economic benefits of scale-up. Developments of much more powerful ion sources have further extended the potential for industrial applications of gaseous and metallic ion beams. The combination of coating and ion implantation for ion beam assisted deposition and diamond-like carbon deposition has provided additional versatility. Future trends and prospects will be discussed, including the opportunities for plasma-based methods of ion implantation.