Negative ion volume production in electron cyclotron resonance hydrogen plasmas

Production and control of electron cyclotron resonance (ECR) plasmas for negative ion sources have been studied. A new production method using permanent magnets is proposed as one possibility for generating a large-diameter high-density uniform microwave plasma. The microwave power is launched by an annular slot antenna into the circumference of a chamber with a ring-cusp or a line-cusp permanent magnet, where a magnetic field can be applied in a local region and plasmas can be efficiently generated if ECR condition is satisfied. In this paper, we report the structure of the ECR negative ion source, the characteristics of the ECR plasmas, and the comparison of the ECR plasmas with DC discharge plasmas from the viewpoint of a negative ion source. (author)