Amorphous-Nanocrystalline Transition in Silicon Thin Films Obtained by Argon Diluted Silane PECVD


The Plasma-Enhanced Chemical Vapor Deposition (PECVD) method is widely used compared to other methods to deposit hydrogenated silicon Si:H. In this work, a systematic variation of deposition parameters was done to study the sensitivities and the effects of these parameters on the intrinsic layer material properties. Samples were deposited with 13.56 MHZ PECVD through decomposition of silane diluted with argon. Undoped samples depositions were made in this experiment in order to obtain the transition from the amorphous to nanocrystalline phase materials. The substrate temperature was fixed at 200oC. The influence of depositions parameters on the optical proprieties of the thin films was studied by UV-Vis-NIR spectroscopy. The structural evolution was also studied by Raman spectroscopy and X-ray diffraction (XRD). The structural evolution studies show that beyond 200 W radio frequency power value, we observed an amorphous-nanocrystalline transition, with an increase in crystalline fraction by increasing RF power and working pressure. The deposition rates are found in the range 6 - 10 /s. A correlation between structural and optical properties has been found and discussed.

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Amrani, R. , Pichot, F. , Chahed, L. and Cuminal, Y. (2012) Amorphous-Nanocrystalline Transition in Silicon Thin Films Obtained by Argon Diluted Silane PECVD. Crystal Structure Theory and Applications, 1, 57-61. doi: 10.4236/csta.2012.13011.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] W. E. Spear and P. G. LeComber, “Subtitutional Doping of Amorphous Silicon,” Solid State Communications, Vol. 17, No. 9, 1975, pp. 1193-1196. doi:10.1016/0038-1098(75)90284-7
[2] D. L. Staebler and C. R. Wronki, “Reversible Conductivity Changes in Discharge Produced Amorphous Si,” Applied Physical Letters, Vol. 31, No. 4, 1977, p. 292. doi:10.1063/1.89674
[3] H. Li, R. H. Franken, R. L. Stolk, C. H. M. van der Werf, J. K. Rath and R. E. I. Schropp, “Controlling the Quality of Nanocrystalline Silicon Made by Hot-Wire Chemical Vapor Deposition by Using a Reverse H2 Profiling Technique,” Journal of Non-Crystalline Solids, Vol. 354, No. 19-25, 2008, pp. 2087-2091.
[4] M. Birkholz, B. Selle, E. Conrad, K. Lips and W. Fuhs, “Evolution of Structure in Thin Microcrystalline Silicon Films Grown by Electron-Cyclotron Resonance Chemical Vapor Deposition,” Journal of Applied Physics, Vol. 88, No. 7, 2000, pp. 4376-4379. doi:10.1063/1.1289783
[5] B. Rech, T. Roschek, J. Müller, S. Wieder and H. Wagner, “Amorphous and Microcrystalline Silicon Solar Cells Prepared at High Deposition Rates Using RF (13.56 MHz) Plasma Excitation Frequencies,” Solar Energy Materials and Solar Cells, Vol. 66, No. 1-4, 2001, pp. 267-273. doi:10.1016/S0927-0248(00)00183-5
[6] Y. Mai, S. Klein, R. Carius, L. Houben, X. Geng and F. Finger, “Improvement of Open Circuit Voltage in Micro-crystalline Silicon Solar Cells Using Hot Wire Buffer Layers,” Journal of Non-Crystalline Solids, Vol. 352, No. 9-20, 2006, pp. 1859-1862.
[7] M. van Veen, C. van der Werf and R. Schropp, “Tandem Solar Cells Deposited Using Hot-Wire Chemical Vapor Deposition,” Journal of Non-Crystalline Solids, Vol. 338-340, No. 1, 2004, pp. 655-658. doi:10.1016/j.jnoncrysol.2004.03.071
[8] R. Amrani, D. Benlekehal, R. Baghdad, D. Senouci, A. Zeinert, K. Zellama, L. Chahed, J. D. Sib and Y. Bouizem, “Low-Temperature Growth of Nanocrystalline Silicon Films Prepared by RF Magnetron Sputtering: Structural and Optical Studies,” Journal of Non-Crystalline Solids, Vol. 354, No. 19-25, 2008, pp. 2291-2295. doi:10.1016/j.jnoncrysol.2007.10.044
[9] J. L. Dorier, C. Hollenstein, A. A. Howling and U. Kroll, “Powder Dynamics in Very High Frequency Silane Plasmas,” Journal of Vacuum Science & Technology, Vol. A10, No. 4, 1992, pp. 1048-1052. doi:10.1116/1.578200
[10] J. L. Dorier, C. Hollenstein and A. A. Howling, “Spatiotemporal Powder Formation and Trapping in Radio Frequency Silane Plasmas Using Two-Dimensional Polarization-Sensitive Laser Scattering,” Journal of Vacuum Science & Technology, Vol. A13, No. 3, 1995, pp. 918-926. doi:10.1116/1.579852
[11] A. A. Howling, J. L. Dorier, C. Hollenstein, U. Kroll and F. Finger, “Frequency Effects in Silane Plasmas for Plasma Enhanced Chemical Vapor Deposition,” Journal of Vacuum Science & Technology, A10, No. 4, 1992, pp. 1080-1085. doi:10.1116/1.578205
[12] J. L. Dorier,“Genèse, Croissance et Conséquences de Particules Dans les Plasmas en Silane à Basse Pression et Basse Température,” Ph.D. Thesis, E.P.F.L, Switzerland, 1996.
[13] R. Swanpoel, “Determination of the Thickness and Optical Constants of Amorphous Silicon,” Journal of Physics E: Scientific Instruments, Vol. 16, No. 12, 1983, pp. 1214-1222. doi:10.1088/0022-3735/16/12/023
[14] J. C. Manifacier, J. Gasiot and J. P. Fillard, “A Simple Method for the Determination of the Optical Constants n, k and the Thickness of a Weakly Absorbing Thin Film,” Journal of Physics E: Scientific Instruments, Vol. 9, No. 11, 1976, pp. 1002-1004. doi:10.1088/0022-3735/9/11/032
[15] S. H. Wemple and M. Didomenico, “Behavior of the Electronic Dielectric Constant in Covalent and Ionic Materials,” Physical Review B, Vol. 3, No. 4, 1971, pp. 1338-1351. doi:10.1103/PhysRevB.3.1338
[16] P. Scherrer, “Bestimmung der Grosse und Derinneren Struktur von Kolloidteilchen Mittels Rontgenstrahlen,” Nachrichten von der Gesellschaft der Wissenschaften zu Gottingen, Mathematisch-Physikalische Klasse, Vol. 26, No. 1, 1918, pp. 98-100.
[17] G. Yue, J. D. Lorentzien, J. Lin, D. Han and Q. Wang, “Photoluminescence and Raman Studies in Thin-Film Materials: Transition from Amorphous to Microcrystal-line Silicon,” Journal of Applied Physical Letters, Vol. 75, No. 4, 1999, pp. 492-494. doi:10.1063/1.124426
[18] D. Beeman, R. Tsu and M. F. Thorpe, “Structural Information from the Raman Spectrum of Amorphous Silicon,” Physical Review B, Vol. 32, No. 2, 1985, pp. 874-878. doi:10.1103/PhysRevB.32.874
[19] Y. He, C. Yin, G. Cheng, L. Wang, X. Liu and G. H. Hu, “The Structure and Properties of Nanosize Crystalline Silicon Films,” Journal of Applied Physics, Vol. 75, No. 2, 1994, pp. 797-803. doi:10.1063/1.356432
[20] E. C. Freeman and W. Paul, “Optical Constants of rf Sputtered Hydrogenated Amorphous Si,” Physical Review B, Vol. 20, No. 1, 1979, pp. 716-728. doi:10.1103/PhysRevB.20.716

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