IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Plasma Science Monday Sessions
       Session PS-MoP

Paper PS-MoP13
Species Characterization in Inductively Driven Fluorocarbon Etch Plasmas

Monday, October 29, 2001, 5:30 pm, Room 134/135

Session: Plasma Diagnostics and Plasma-Surface Interactions Poster Session
Presenter: G.A. Hebner, Sandia National Laboratories
Authors: G.A. Hebner, Sandia National Laboratories
I.C. Abraham, Sandia National Laboratories
Correspondent: Click to Email
A number of techniques have been used to characterize etching plasmas containing fluorocarbon gases. Laser induced fluorescence was used to measure the spatially resolved SiF and SiF@sub 2@ densities in inductively driven discharges containing C@sub 2@F@sub 6@ and C@sub 4@F@sub 8@. Measurements of the spatially resolved SiF and SiF@sub 2@ densities were performed as functions of the induction coil power, pressure, and bias power above a silicon surface. The SiF density had a maximum at a radial distance of 2 - 3 cm from the center of the plasma, and then monotonically decreased towards the edge of the plasma region. The SiF@sub 2@ density had a maximum at a radial distance of approximately 7 cm from the center of the plasma. Electron and negative ion densities was measured in C@sub 4@F@sub 8@ and the identity of the negative ions in C@sub 2@F@sub 6@, CHF@sub 3@ and C@sub 4@F@sub 8@ containing discharges was investigated using a novel photodetachment experiment. To investigate the influence of surface material, the rf biased electrode was covered with a silicon wafer or a fused silica (SiO@sub 2@) wafer. In most cases, the trends in the electron and negative ion density were independent of the wafer material. A novel microwave resonant cavity structure was developed to identify the negative ions using laser photodetachment spectroscopy. Unlike traditional microwave cavity techniques, this method offers the possibility of spatial resolution. This work was supported by SEMATECH and the United States Department of Energy (DE-AC04-94AL85000).