Techniques for Adding useful Functions to Carbon Surfaces by Cold Plasmas

Abstract

Methods of generation, diagnosis, control and application to carbon materials on cold plasmas are related from the standpoint of techniques for adding useful functions to carbon surfaces by the plasmas. Cold plasma has been used in many fields, such as semiconductor fabrication, diamond synthesis and surface improvement of various materials. In case of using cold plasmas, it is necessary to know their merits and demerits on the application. Also, methods of their generation, diagnosis and control are important. Becase the cold plasmas are generated mainly by discharges, such as corona discharge, glow discharge and arc discharge, these plasma generation methods are stated. With respect to diagnosis methods, the single probe method and the double probe method, which are used frequently for the application of the plasmas, are described in detail. Plasma control is one of the most important techniques for the surface modification. Sheath voltage control is a method for energy control of the incident ions onto the material surface, which influences the characteritics of the surface. Several methods for it are shown in this paper. By using these methods of generation, diagnosis and control of plasma, useful functions could be given to carbon surfaces. These techniques are related. The accurate, damage-less and wide-range control of wettability on carbon surface without temporal change became possible. A basic study for modifying the three-dimensinal materials was carried out. Damage-less etching was made without decreasing etching rate. Surface modification by using plasmas has posibilities on adding various more excellent functions to carbon material surfaces