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Indexed by:期刊论文

Date of Publication:2014-10-01

Journal:PHYSICS OF PLASMAS

Included Journals:SCIE、EI、Scopus

Volume:21

Issue:10

ISSN No.:1070-664X

Abstract:Broadband ultraviolet absorption spectroscopy has been used to determine the CF2 radical density in dual-frequency capacitively coupled CF4/Ar plasmas, using the CF2 (A) over tilde B-1(1) <- (X) over tilde (1)A(1) system of absorption spectrum. The rotational temperature of ground state CF2 and excited state CF was also estimated by using (A) over tilde B-1(1) <- (X) over tilde (1)A(1) system and B-2 Delta - X-2 Pi system, respectively. The translational gas temperature was deduced from the Doppler width of the Ar*(P-3(2)) and Ar*(P-3(0)) metastable atoms absorption line by using the tunable diode laser absorption spectroscopy. The rotational temperatures of the excited state CF are about 100K higher than those of ground state CF2, and about 200K higher than the translational gas temperatures. The dependences of the radical CF2 density, electron density, electron temperature, rotational temperature, and gas temperature on the high frequency power and pressure have been analyzed. Furthermore, the production and loss mechanisms of CF2 radical and the gas heating mechanisms have also been discussed. (C) 2014 AIP Publishing LLC.