AVS 47th International Symposium
    MEMS Wednesday Sessions
       Session MM-WeM

Paper MM-WeM4
Optical Emission Study of a Microfabricated Inductively Coupled Plasma

Wednesday, October 4, 2000, 9:20 am, Room 309

Session: Microfabricated Sensors
Presenter: O. Minayeva, Northeastern University
Authors: O. Minayeva, Northeastern University
J.A. Hopwood, Northeastern University
Correspondent: Click to Email
Recently, the fabrication@footnote 1,2@ and characterization@footnote 3,4@ of a micromachined 5-mm inductively coupled plasma (ICP) generator was reported. One of the applications for a microplasma source is the detection of gaseous impurities in air using a micromachined Fabry-Perot interferometer to monitor the optical emissions of the plasma. In this work the complete system that includes a microplasma generator, vacuum chamber, optical path, and lab-scale spectrometer was built and tested on several gas discharges. The goal was to maximize the electronic excitation reaction followed by the light emission from a toxic gas sample (e.g., SO@sub 2@) diluted in air (or argon). It was found that an electron temperature of ~3 eV favors the excitation reaction for SO@sub 2@. The chamber was designed to provide this value of electron temperature over an operating pressure of 0.5-1 torr. Optical paths were incorporated in the chamber in order to collimate the plasma's light emission to within 3-4@super o@ prior to filtering and detection by the interferometer. Multiple optical paths also allow one to determine the spatial structure of the plasma. The optical emission spectra were taken at different points within the micro ICP, and the results on light intensity distribution across the discharge will be presented. @FootnoteText@ @footnote 1@ J. Hopwood, "Monolitic miniaturized inductively coupled plasma source;" U.S. Patent No. 5,942,855 (August 24, 1999). @footnote 2@ Y. Yin, J. Messier, and J. Hopwood, "Miniaturized inductively coupled plasma sources," IEEE Transactions on Plasma Science, 27(5), 1516-1524, (1999). @footnote 3@ J. Hopwood, O. Minayeva, Y. Yin, "Fabrication and characterization of a micromachined 5-mm inductively coupled plasma generator," submitted to J. Vac. Sci. Technol. @footnote 4@ J. Hopwood, "A microfabricated inductively-coupled plasma generator," submitted to J. Microelectromechanical Systems.