AVS 45th International Symposium
    Plasma Science and Technology Division Thursday Sessions
       Session PS-ThP

Paper PS-ThP6
Time Resolved Electrostatic Probe Measurements of Electron Temperature and Plasma Density Radial Profiles in a Pulsed ICP Plasma

Thursday, November 5, 1998, 5:30 pm, Room Hall A

Session: Plasma Science and Technology Division Poster Session
Presenter: X.M. Tang, College of William and Mary
Authors: X.M. Tang, College of William and Mary
D.M. Manos, College of William and Mary
Correspondent: Click to Email
This paper reports results of a study of a pulsed 13.6 MHz ICP plasma which has been configured for multiple purposes, including etch, cleaning, and deposition. The pulse-packet frequency can be varied over a wide range. For these studies it was varied from 50Hz to 10kHz to create plasmas in a variety of gas mixtures including oxygen, carbon tetrafluoride, and argon. The plasma is characterized using a variety of methods, including electrostatic probes and optical emission. Probe data were analyzed using nonlinear regression methods and equivalent resistance methods. The comparative advantages of each will be discussed. The agreement between the methods is good. Spatially resolved measurements of the time-dependent electron density and temperature, taken on the time scale of the power modulation, are presented as a function of rf power, frequency, duty cycle, and gas composition. These results confirm, among other things, that the modulated plasma density is higher than the plasma density resulting from CW operation at the same average power. High-temperature transients at the pulse onset do not appear at high frequencies. Comparisons with similar prior studies and with simulated plasma models will also be presented.