Surface sterilization with high energy ions

Summary form only given. There is a need for sterilization approaches that will deal with bacterial spores on a short time scale and without chemical agents. High-energy (e.g. 50 keV) ions, extracted from a low-density plasma using an ion implantation approach, have the theoretical potential for sufficient spore damage to preclude germination. The high dose rate, resulting from a modest ion current density to the surface to be sterilized, is a product of the short stopping distance for the implanted ions. This approach features a low density plasma, formed under modest vacuum conditions, with a short (e.g. 10 micro second) surface bias pulse to develop a high energy ion current. Hydrogen ions provide the best penetration and hydrogen is therefore the working gas of choice. Tests are underway to demonstrate this approach as a sterilization option for plastic containers.