Downstream Plasma Delivery From a Remote VHF Source

Abstract

A new remote plasma source (RPS) driven by capacitively coupled VHF power is investigated and compared with alternative technologies. The generation of plasma by high frequency capacitive coupling, opposed to inductive coupling, results in noticeable differences in plasma behaviors. Plasma densities near the output of the source are high as expected from both approaches. Uniquely, with the VHF source, significant plasma can be delivered downstream to a remote chamber at densities far exceeding what is demonstrated from the more confined ICP alternatives. This paper describes this plasma projection behavior of a VHF CCP source and presents plasma parameters including density, current and ion energy measured at the output and downstream into both confined and expanded chamber volumes. The behaviors of different gases including argon, nitrogen and hydrogen are contrasted to show the influence from chemistry on the projected plasma behaviors. References 11