Patent ID: 8334027

Claim:
A method for depositing a material in the absence of a positive column, comprising a cleaning step and a depositing step, wherein the cleaning step comprises a) introducing a hydrogen gas to a chamber, and b) performing a cleaning for each surface of a cathode and an anode in the chamber by a cathode glow and an anode glow, wherein the cathode glow and the anode glow are generated by a plasma discharge under a hydrogen gas pressure of 50 to 400 Torr, wherein the depositing step comprises i) introducing a chamber gas comprised of methane, nitrogen and hydrogen into the chamber with a chamber gas pressure of 50 to 400 Torr, wherein Ar gas is not used as a part of the chamber gas, ii) generating a plasma discharge between the cathode and the anode by applying a DC voltage, wherein the cathode and the anode face each other with a distance of less than 5 mm, and iii) depositing a material containing nano-crystalline diamond on the anode or on a substrate mounted on the anode, under existence of a cathode glow and an anode glow; and wherein the cathode is formed of tungsten.