AVS 50th International Symposium
    Plasma Science and Technology Tuesday Sessions
       Session PS-TuP

Paper PS-TuP14
Plasma Frequency Measurements for Absolute Plasma Density by Means of Wave Cutoff Method

Tuesday, November 4, 2003, 5:30 pm, Room Hall A-C

Session: Poster Session
Presenter: J.H. Kim, Korea Research Institute of Standards and Science
Authors: J.H. Kim, Korea Research Institute of Standards and Science
Y.H. Shin, Korea Research Institute of Standards and Science
K.H. Chung, Korea Research Institute of Standards and Science
Correspondent: Click to Email
A plasma oscillation method@footnote 1@ and a plasma absorption method@footnote 2,3@ have been used for measurements of absolute electron density in a plasma. In this report, a newly designed method for precise measurements of absolute electron density in the plasma using plasma frequency is described. A microwave perturbation of a frequency is introduced to plasma from a network analyzer and transmits in the plasma. The transmitted wave at a distance from a radiating antenna is monitored using spectrum analyzer as scanning the perturbing frequency. The transmitted wave rapidly decays by wave cutoff at the plasma frequency, which gives the absolute electron density. The propagating waves of some frequency including plasma frequency are characterized. The measured plasma frequency by this method is coincident with that obtained by the plasma oscillation method. The measured plasma densities are also compared with those got by using a double Langmuir probe over wide parameter range (gas composition, input power and gas pressure). @FootnoteText@ @footnote 1@T. Shirakawa and H. Sugai, Jpn. J. Appl. Phys. Vol. 32, 5129 (1993). @footnote 2@H. Kokura et al., J. Appl. Phys. Vol. 38, 5262 (1999). @footnote 3@K. Nakamura et al., J. Vac. Sci. Technol.A 21, 325 (2003).