Investigation of ECR plasma uniformity from the point of view of production and confinement

To clarify the production mechanism of a high-density uniform electron cycl otron resonance (ECR) plasma, the spatial wave patterns of electromagnetic waves in the plasma were measured by the interferometric method under sever al experimental conditions and compared with the power absorption profiles indicated by simulation. It was experimentally shown that the refraction of the right circularly polarized wave (the R wave) corresponds to the spatia l profile of the plasma density. On the other hand, the simulation showed t he correlation between the wave refraction and power absorption, which impl ies that the power transportation depending upon the refraction of the R wa ve has a great influence on ECR plasma uniformity. Furthermore, it was foun d that the plasma uniformity was improved by applying permanent magnets, an d the maximum electron density in the case of the uniform plasma is approxi mately 2 x 10(11) cm(-3). The ion temperature in the Ar plasma decreases fr om 0.17 to 0.06 eV in the presence of the permanent magnets. (C) 2001 Elsev ier Science B.V. All rights reserved.