Electromagnetic wave propagation in an ECR plasma

Experiments on the production of a large diameter ECR plasma with microwaves of 2.45 GHz frequency are reviewed. It is pointed out that the electromagnetic waves play an important role in the uniformity as well as the production of an ECR plasma. Furthermore, it is found that the X wave contributes to plasma uniformity for an electron density of (1–2)×1017 m−3 at approximately the L cutoff. Mode conversion is also observed near the chamber, which is compared with a simulation.