Estimation of Electron Temperature and Frequency Components in a Dual Frequency Capacitively-Coupled Plasma Processing Reactor

The measurement of electron temperature in RF plasma sources with Langmuir probes is difficult because of the influence of rf noise. We attempted to estimate the electron temperature in a capacitively-coupled plasma processing reactor with a Surface Wave Probe [1] which employs microwaves. We also estimated the frequency spectrum with the sensitive PAP [1, 2]. We measured the harmonics which appeared in the bulk plasma for various experimental conditions in the dual-frequency [60 MHz and 2MHz] capacitively-coupled plasma processing reactor. We estimated RF power spectra for several experimental conditions like RF power [500-2000W], gas pressure [3-20Pa], and gas species [Ar, CF$_4$]. The measurement results suggest the existence of energy transport among several frequency spectrum. \\[1ex] [1] K. Nakamura, M. Ohata, and H. Sugai: J. Vac. Sci. Technol. A \textbf{21}, 325 (2003). \\[0pt] [2] T. Shirakawa and H. Sugai : Jpn. J. Appl. Phys. \textbf{32}, 5129 (1993).