Gas flows in plasma etching reactors for semiconductor fabrication became a chief consideration in designing second-generation reactors with higher etching rates. An axisymmetrical model based on the direct simulation Monte Carlo method has been developed for analyzing rarefied gas flows in a vacuum chamber with the conditions of downstream pressure and gas flow rate. By using this simulator, rarefied gas flows with radicals and etch-products were calculated for microwave-plasma etching reactors. The results showed that the flow patterns in the plasma chamber strongly depend on the Knudsen number and the gas-supply structure. The ventilation of the etch-products in the plasma chamber was found to be improved both for higher Knudsen numbers and for gas-supply structures of the downward-flow type, as compared with those of the radial-flow or upward-flow types.
Issue Section:
Additional Technical Papers
1.
Tsujimoto, K., Kumihashi, T., Kofuji, N., and Tachi, S., 1992, “High-Gas-Flow-Rate Microwave Plasma Etching,” Proceedings of Symposium on Dry Process (Oct., 1992 Tokyo), pp. 49–54.
2.
Birdsall
, C. K.
, 1991
, “Particle-in-Cell Charged-Particle Simulations, Plus Monte Carlo Collisions With Neutral Atoms, PIC-MCC
,” IEEE Trans. Plasma Sci.
, 19
(2
), pp. 65
–85
.3.
Ventzek
, P. L. G.
, Hoekstra
, R. J.
, and Kushner
, M. J.
, 1994
, “Two-Dimensional Modeling of High Plasma Density Inductively Coupled Sources for Materials Processing
,” J. Vac. Sci. Technol.
, B12
(1
), pp. 461
–477
.4.
Bukowski
, J. D.
, and Graves
, D. B.
, 1996
, “Two-dimensional Fluid Model of an Inductively Coupled Plasma with Comparison to Experimental Spatial Profiles
,” J. Appl. Phys.
, 80
(5
), pp. 2614
–2623
.5.
Shufflebotham
, P. K.
, Bartel
, T. J.
, and Berney
, B.
, 1995
, “Experimental Validation of a Direct Simulation by Monte Carlo Molecular Gas Flow Mode
,” J. Vac. Sci. Technol.
, B13
(4
), pp. 1862
–1866
.6.
Economou
, D. J.
, Bartel
, T. J. M.
, Wise
, R. S.
, Lymberopoulos
, D. P.
, and Shufflebotham
, P. K.
, 1995
, “Two-Dimensional Direct Simulation Monte Carlo (DSMC) of Reactive Neutral and Ion Flow in a High Density Plasma Reactor
,” IEEE Trans. Plasma Sci.
, 23
(4
), pp. 581
–590
.7.
Serikov
, V. V.
, Kurisawa
, S.
, and Nanbu
, N.
, 1996
, “Profile of Al Etch Rate Estimated from the Analysis of 3-D Rarefied Flow of Cl2, BCl3, and AlCl3 In a Commercial Etcher
Vacuum
,” 47
(6–8
), pp. 1027
–1029
.8.
Font
, G. I.
, and Boyd
, I. D.
, 1997
, “Numerical Study of the Effects of Reactor Geometry on a Chlorine Plasma
,” J. Vac. Sci. Technol.
, 15
(2
), pp. 313
–319
.9.
Nanbu
, K.
, and Suetani
, M.
, 1997
, “DSMC Analysis of Rarefied Flows of Chlorine in a Parallel-Plate RF Etcher for 300 mm Wafer
,” Reports of the Institute of Fluid Science, Tohoku University, 10
, pp. 283
–289
.10.
Johannes
, J.
, Bartel
, T.
, Hebner
, G. A.
, Woodworth
, J.
, and Economou
, D. J.
, 1997
, “Direct Simulation Monte Carlo of Inductively Coupled Plasma and Comparison with Experiment
,” J. Electrochem. Soc.
, 144
(7
), pp. 2448
–2455
.11.
Hash
, D.
, and Meyyappan
, M.
, 1997
, “A Direct Simulation Monte Carlo Study of Flow Considerations in Plasma Reactor Development for 300 mm Processing
,” J. Electrochem. Soc.
, 144
(11
), pp. 3999
–4004
.12.
Nanbu
, K.
, Morimoto
, T.
, and Suetani
, M.
, 1999
, “Direct Simulation Monte Carlo Analysis of Flows and Etch Rate in an Inductively Coupled Plasma Reactor
,” IEEE Trans. Plasma Sci.
, 27
(5
), pp. 1379
–1388
.13.
Bird, G. A., 1976, Molecular Gas Dynamics, Clarendon Press, Oxford.
14.
Ikegawa
, M.
, Kakehi
, Y.
, and Kobayashi
, J.
, 1992
, “One-Dimensional Modeling for Magneto-Microwave Plasma Using the Monte Carlo Method
,” Jpn. J. Appl. Phys.
, 31
(6B
), Part 1, pp. 2030
–2034
.15.
Tanaka, J., and Ikegawa M., 1994, “Study of Wave Propagation and Plasma Generation in ECR Plasmas by Numerical Simulation,” Proceedings of 2nd International Conference on Reactive Plasmas, Jan., Yokohama, pp. 729–732.
16.
Ikegawa
, M.
, and Kobayashi
, J.
, 1990
, “Development of a Rarefied Gas Flow Simulator Using the Direct-Simulation Monte Carlo Method (2-D Flow Analysis with the Pressure Conditions Given at the Upstream and Downstream Boundaries)
,” JSME Int. J., Ser. II
, 33
(3
), pp. 463
–467
.17.
Ikegawa
, M.
, Kobayashi
, J.
, and Maruko
, M.
, 1998
, “Study on the Deposition Profile Characteristics in the Micron-Scale Trench Using Direct Simulation Monte Carlo Method
,” ASME J. Fluids Eng.
, 120
, pp. 296
–302
.18.
Ikegawa M., Usui, T., and Tanaka, J., 1994, “Rarefied Gas Flow Analyses in Plasma Etching Apparatuses Using the Direct Simulation Monte Carlo Method,” Proceedings of JSME Fluids Engineering Conference, No. 940–53, pp. 271–272 (in Japanese).
19.
Ikegawa, M., Ogawa, Y., Usui, T., and Tanaka, J., 1995, “Rarefied Gas Flow Analyses in Plasma Etching Apparatuses Using the Direct Simulation Monte Carlo Method (2nd Rep.: Effect of Gas Supply Structure on the Flow Field),” Proceedings of the 72nd JSME Spring Annual Meeting, No. 95-1, pp. 193–194 (in Japanese).
20.
Danner
, D. A.
, and Hess
, D. W.
, 1986
, “Reaction of Atomic and Molecular Chlorine with Aluminum
,” J. Appl. Phys.
, 59
(3
), pp. 940
–947
.21.
Nanbu
, K.
, 1996
, “Stochastic Solution Method of the Boltzmann Equation II. Simple Gas, Gas Mixture, Diatomic Gas, Reactive Gas, and Plasma
,” Reports of the Institute of Fluid Science, Tohoku University, 8, pp. 77
–125
.22.
Edited by Manos, D. M., and Flamm, D. L., 1989, Plasma Etching—An Introduction, Academic Press, San Diego, p. 153.
23.
Ikegawa
, M.
, Kobayashi
, J.
, and Fukuyama
, R.
, 2001
, “Effects of Gas-Flow Structures on Radical and Etch-Product Density Distribution on Wafers in Magnetomicrowave Plasma Etching Reactors
,” J. Vac. Sci. Technol.
, A 19
(2
), pp. 460
–466
.24.
Kobayashi
, J.
, Nakazato
, N.
, and Hiratsuka
, K.
, 1989
, “Numerical Simulation for Gas Flow and Mass Transfer in a Dry Etching Chamber
,” J. Electrochem. Soc.
, 136
, No. 6
, pp. 1781
–1786
.25.
Tachi, S., 1983, “Al and Si Etching Mechanism-hot Spot Model,” Proceedings of 5th Symposium on Dry Process, pp. 8–13.
Copyright © 2002
by ASME
You do not currently have access to this content.
