Quasistatic Plasma Sources : Physical Principles, Modelling Experiments, Application Aspects

Abstract
Magnetic field enhanced rf plasma sources excited by frame-type antennas (quasistatic plasma sources) are treated theoretically and experimentally. The theoretical model predicts that a significant part of the rf power is absorbed in a source plasma via the excitation of quasi-electrostatic waves. The dependences of absorption on plasma density, external magnetic field, driving frequency, and source dimensions (scaling laws) are obtained. Special experiments on low-power rf signal absorption in a preformed dense plasma corroborate well the theory. Results of test experiments with different sources have shown that a behaviour of the discharge in quasistatic sources is in good agreement with theoretical predictions. Using this knowledge, a compact low-power ion source was designed and optimized. Detailed testing of its parameters has shown that this device has good prospects for use as an ion thruster, and for various materials processing applications.