AVS 50th International Symposium
    Plasma Science and Technology Wednesday Sessions
       Session PS-WeP

Paper PS-WeP11
Experimental Characterization of a Pulsed Inductively Coupled Plasma

Wednesday, November 5, 2003, 11:00 am, Room Hall A-C

Session: Poster Session
Presenter: C.H. Chang, National Tsing Hua University, ROC
Authors: C.H. Chang, National Tsing Hua University, ROC
K.C. Leou, National Tsing Hua University, ROC
S.J. Wu, National Tsing Hua University, ROC
M.L. Gong, National Tsing Hua University, ROC
T.L. Lin, National Tsing Hua University, ROC
Correspondent: Click to Email
The basic properties of a pulsed low pressure inductively-coupled plasma has been characterized by using various diagnostic tools, including a RF impedance meter, a Langmuir probe, a 36 GHz interferometer and optical emission spectroscopy. These tools have been modified from conventional ones to measure time resolved properties of the discharge. In addition to plasma density, plasma potential and electron temperature, the Langmuir probe has also been used to extract the electron energy probability function (EEPF) of the plasma. Measurement results show that high energy (roughly E > 10 eV) electrons are lost quickly after the driving RF power is turned off. The low energy part of the electrons remains nearly unchanged during the entire off period. The electron temperature thus drops quickly while plasma density changes little during RF off period as observed in other studies. Spatial-temporal behaviors of plasma density have also been measured. The radial distribution of plasma density only change slightly at different times of the RF on or off periods although the overall plasma density varies significantly. The electric properties of the discharge was measured by a home made impedance meter which detects the time varying amplitude and phase of the RF voltage and current, and thus net input RF power and complex impedance of the discharge. For different waveforms of modulation, such as square, triangular, sinusoidal and trapezoidal, impedance meter measurements show that, when the RF power is turned on, there is always a transient surge of RF voltage and current on the inductive coil, thus the net input power into the plasma. The temporal profiles of electric properties, however, do not vary significanly for different types of modulations. Comparison of probe and impedance meter measurements to interferometer and OES measurements will also be presented. @FootnoteText@ Work supported by the NSC of the R.O.C., grant No. NSC 90-2622-E-007-004.