TRANSMISSION LINE BASED INDUCTIVELY COUPLED PLASMA SOURCE WITH STABLE IMPEDANCE

摘要

A properly designed and positioned Faraday shield/dielectric spacer/source-coil assembly is used to nearly fix the input impedanceof an Inductively Coupled Plasma (ICP) source-coil (130), making a variable matching network almost unnecessary, and allowing for pulsed plasma processing with very little reflected power. This is not possible without a properly designed and positioned Faraday shield (150) because the source-coil impedance is coupled to that of the plasma and changes significantly with the plasma conditions. The ICP source-coil/dielectric spacer/Faraday shield assembly can then be designed to optimize the symmetry of the plasma generation independent of plasma conditions by varying the source structure (130), dielectric spacer material, dielectric spacer structure (140), and Faraday shield structure (150). An appropriately positioned aperture in the Faraday shield can allow enough capacitive coupling between to ignite the plasma while preventing any significant capacitive coupling.