Abstract
This article present experimental data on spectrophotometric measurements in an oxygen plasma for different values of
radio-frequency 1.56MHz(rf) power and pressure in an asymmetrical industrial OPT Plasmalab 100 system used for
semiconductor etching. The method for characterizing ion and atom energies is to examine the Doppler profile of their
emission lines. The energies derived from the emission profiles depend on the operating power and pressure. The signals
were deconvoluted and the resulting profiles were fit with a Gauss-ian line-shape function whose full width at half-maximum
was used as a measure of the Doppler width. While term “temperature” may not accurately describe the ion energetics in an
rf plasma source, the Doppler profile does provide a useful basis for a relative comparison of ion motion under a variety of
operating conditions. A simple mathematical model was applied to calculate atomic and ionic temperature and a good
concordance with Doppler method has been found..
Keywords
Oxygen plasma, Doppler profile, Optical emission spectroscopy, Plasma temperature, Langmuir probe.
Citation
M. AFLORI, D. O. DOROHOI, D. G. DIMITRIU, Spectrophotometric measurements in an rf capacitively-coupled oxygen discharge, Optoelectronics and Advanced Materials - Rapid Communications, 2, 8, August 2008, pp.478-481 (2008).
Submitted at: June 24, 2008
Accepted at: July 16, 2008