Optical emission, electron energy, density, wave magnetic field and spectrum measurements in a helicon plasma source

• Main Authors: Scharer, J., White, B., Tysk, S., Paller, E., Akhtar, K.
• Format: Conference Proceeding
• Language: English
• Subjects: Density measurement; Electron emission; Electron optics; Energy measurement; Magnetic analysis; Magnetic field measurement; Plasma density; Plasma measurements; Plasma sources; Stimulated emission
• DOI: 10.1109/PLASMA.2002.1030478

Summary form only given. Measurements and analysis of optical emission, electron energy analyzer, Langmuir and magnetic probe and wave spectra are presented for a wide range of helicon plasma source conditions. Helicon plasma source characteristics at lower argon neutral pressures of 2-6 mTorr at both low (200 G) and high (1.2 kG) magnetic field strengths and at high pressures (100 mTorr) are presented for a wide range of radiofrequency input powers. Plasma densities in the range of 10/sup 11/-10/sup 13//cm/sup 3/ are obtained in the UW helicon facility which utilizes a double half-turn helix. Observations of Ar II emission, its modulation and correlation with the RF phase are presented in both time and spatial domains for a variety of plasma conditions. The emission spectrum measured by optical probes either internal or external to the 10 cm diameter Pyrex cylinder plasma is compared with wave magnetic and plasma density as well as miniaturized electron energy analyzer measurements. In addition, both low frequency, fundamental, sideband and harmonic components of the RF wave are measured and analyzed to obtain a comprehensive picture of the helicon source operation for a variety of conditions. Network analyzer measurements, Antenna II wave modeling and wave-particle ionization models are used to analyze the properties of the plasma source.