INFRARED-LASER DIAGNOSTICS IN METHANE CHEMICAL-VAPOR-DEPOSITION PLASMAS

被引:24
作者
DAVIES, PB
MARTINEAU, PM
机构
[1] Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, Lensfield Road
关键词
D O I
10.1063/1.351361
中图分类号
O59 [应用物理学];
学科分类号
摘要
Tunable diode laser absorption spectroscopy has been used to measure the concentrations of reactive species in an rf (20 kHz) chemical-vapor-deposition reactor as a function of methane flow rate, pressure, current, and added inert gas. The IR measurements have been supplemented by mass spectrometry and optical emission spectroscopy. The reactive hydrocarbon species detected by IR were CH4, C2H2, C2H4, and C2H6, and the free radical CH3. No significant spatial variation in methyl radical concentration was measured between the parallel-plate electrodes under our conditions. The growth rate of amorphous carbon films on the lower (ground) electrode was found to vary linearly with the concentration of CH3 measured close to this electrode, and these results are compatible with a CH3 sticking coefficient of less-than-or-equal-to 0.02. One-dimensional modeling calculations using the FACSIMILE program were carried out to simulate the variation of the concentration of the principle species with current (electron number density). Satisfactory agreement with the measurements of CH4, CH3, and C2H6 concentrations was obtained when ionization and ion molecule reactions, as well as reactions of neutral species, were included in the chemical model.
引用
收藏
页码:6125 / 6135
页数:11
相关论文
共 22 条
[1]   SPATIALLY AND TEMPORALLY RESOLVED LASER-INDUCED FLUORESCENCE MEASUREMENTS OF CF2 AND CF RADICALS IN A CF4 RF PLASMA [J].
BOOTH, JP ;
HANCOCK, G ;
PERRY, ND ;
TOOGOOD, MJ .
JOURNAL OF APPLIED PHYSICS, 1989, 66 (11) :5251-5257
[2]   INSITU, REAL-TIME DIAGNOSTICS OF OMVPE USING IR-DIODE LASER SPECTROSCOPY [J].
BUTLER, JE ;
BOTTKA, N ;
SILLMON, RS ;
GASKILL, DK .
JOURNAL OF CRYSTAL GROWTH, 1986, 77 (1-3) :163-171
[3]   INFRARED DETECTION OF GASEOUS SPECIES DURING THE FILAMENT-ASSISTED GROWTH OF DIAMOND [J].
CELII, FG ;
PEHRSSON, PE ;
WANG, HT ;
BUTLER, JE .
APPLIED PHYSICS LETTERS, 1988, 52 (24) :2043-2045
[4]   MECHANISM OF DIAMOND GROWTH BY CHEMICAL VAPOR-DEPOSITION ON DIAMOND (100), (111), AND (110) SURFACES - C-13 STUDIES [J].
CHU, CJ ;
DEVELYN, MP ;
HAUGE, RH ;
MARGRAVE, JL .
JOURNAL OF APPLIED PHYSICS, 1991, 70 (03) :1695-1705
[5]   INFRARED-LASER SPECTROSCOPY OF THE A 3-SIGMA-G+-C 3-PI-U SYSTEM OF H-2 AND D-2 [J].
DAVIES, PB ;
GUEST, MA ;
JOHNSON, SA .
JOURNAL OF CHEMICAL PHYSICS, 1988, 88 (05) :2884-2890
[6]   INFRARED DIODE-LASER DIAGNOSTICS OF METHANE PLASMAS PRODUCED IN A DEPOSITION REACTOR [J].
DAVIES, PB ;
MARTINEAU, PM .
APPLIED PHYSICS LETTERS, 1990, 57 (03) :237-239
[7]   SIMULATIONS OF HIGH-RATE DIAMOND SYNTHESIS - METHYL AS GROWTH SPECIES [J].
GOODWIN, DG .
APPLIED PHYSICS LETTERS, 1991, 59 (03) :277-279
[8]   SIMULTANEOUS ANALYSIS OF NU2 AND NU4 BANDS OF METHANE [J].
GRAY, DL ;
ROBIETTE, AG .
MOLECULAR PHYSICS, 1976, 32 (06) :1609-1625
[9]  
GUDEMAN SC, 1983, PHYS REV LETT, V59, P727
[10]   MECHANISM FOR DIAMOND GROWTH FROM METHYL RADICALS [J].
HARRIS, SJ .
APPLIED PHYSICS LETTERS, 1990, 56 (23) :2298-2300