ISSN:
1572-8986
Keywords:
Plasma etching
;
CF2 reactions
;
F atom production
;
CF4-O2 plasmas
;
COF reactions
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Technology
Notes:
Abstract Reactions between CF2 and O(3P) have been studied at 295 K in a gas flow reactor sampled by a mass spectrometer. The major reaction for CF2 has been found to be $$CF_2 + O \to COF + F$$ with $$CF_2 + O \to CO + 2F(F_2 )$$ more than a factor of three slower. The rate coefficient for all loss processes for CF2 on reaction with O is (1.8±0.4)×10−11 cm3 s−1. The COF produced in (18) undergoes a fast reaction with O to produce predominantly CO2. $$COF + O \to CO_2 + F$$ It is uncertain from the results whether or not $$COF + O \to CO + FO$$ occurs, but in any event (19) is the major route. The rate coefficient for the loss of COF in this system [i.e., the combined rate coefficients for (19) and (20)] is (9.3±2.1)×10−11 cm3 s−1. Stable product analysis reveals that for each CF2 radical consumed, the following distribution of stable products is obtained: COF2 (0.04±0.02), CO (0.21±0.04), and CO2 (0.75±0.05). Thus COF2, which we assume is produced via $$CF_2 + O \xrightarrow{M} COF_2$$ is a very minor product in this reaction sequence. The measured rate coefficients demonstrate that reactions (18) and (19) are important sources of F atoms in CF4/O2 plasmas.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00568981
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