Effect of capacitive coupling on inductively coupled fluorocarbon plasma processing

This article describes results obtained using various plasma and surface di agnostics in a study of inductively coupled fluorocarbon plasmas in which t he amount of capacitive coupling was systematically varied. It is found tha t the plasma density decreases while the electron temperature increases as the amount of capacitive coupling is increases at a constant source power l evel. The rate at which the dielectric coupling window is eroded is found t o scale with both the peak-to-peak rf voltage and the ion current density, and the dielectric window erosion is found to influence the resulting plasm a gas-phase chemistry. The changes in plasma electrical and chemical charac teristics have a large impact on the surface processes occurring in inducti vely coupled fluorocarbon plasmas such as fluorocarbon deposition, fluoroca rbon etching, SiO2 etching and Si etching. Further, we show how the selecti ve SiO2-to-Si etch process changes with varying capacitive coupling. (C) 19 99 American Vacuum Society. [S0734-2101(99)01806-0].