Temperature controllable cold plasma source for medical applications

There has been increasing use of atmospheric plasma for surface treatment and medical applications because the production of atmospheric pressure plasma at low temperatures - from room temperature to around 100°C - has been feasible for a number of years. Processing of materials that are sensitive to temperature, such as living bodies and polymer materials is not easy. In addition, most kinds of plasma processing are chemical reactions with radicals or high reactive species, so that there are suitable temperatures for each process. In this study, to generate plasmas at optimum temperature for each process, a new plasma source in which the plasma gas temperature can be accurately controllable have been developed. In this plasma source, gas supplied from a cylinder is cooled by a gas-cooling device with liquid nitrogen (-196°C). Then the gas is heated to a desired temperature by a heater, and then plasma is generated.