AVS 52nd International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS-TuP

Paper PS-TuP26
Discharge Electrode Impedance Effect on Harmonics Generation

Tuesday, November 1, 2005, 4:00 pm, Room Exhibit Hall C&D

Session: Plasma Science and Technology Poster Session
Presenter: Y. Yamazawa, Tokyo Electron AT LTD, Japan
Authors: Y. Yamazawa, Tokyo Electron AT LTD, Japan
M. Nakaya, Tokyo Electron AT LTD, Japan
M. Iwata, Tokyo Electron AT LTD, Japan
A. Shimizu, Tokyo Electron AT LTD, Japan
Correspondent: Click to Email
The radio frequency (rf) power is commonly used to excite plasma or biasing the wafer in a plasma reactor for processing of microelectronics materials. Due to the nonlinear behavior of the plasma sheaths, the rf power imposes harmonics of the drive frequency. The generation of the harmonics is of great technological importance, since it contributes significantly to the plasma property and process result. This paper reports the control of the harmonics generation by means of the electrode impedance in a dual-frequency capacitively coupled plasma reactor. The 2nd ,3rd and 4th harmonics of the bias RF frequency were observed to behave with resonant growth by tuning the electrode impedance adequately. A simple nonlinear equivalent circuit model can reproduce the experimental result. A remarkable change in the radial distribution of electron density was observed at the harmonic resonances. This technique can be applied to control the plasma uniformity of the etch chamber. In addition, this technique can be used for reducing chamber-variation by avoiding the unexpected resonance.