Abstract
In this research, diamond-like carbon (DLC) thin films were deposited on silicon substrates by radio-frequency plasma enhanced chemical vapor deposition method using gas mixture of CH4 and Ar. The effect of different CH4/Ar gas ratio on the structure, refractive index, transmission and hardness of the DLC thin films were investigated by means of Raman spectroscopy, ellipsometry, Fourier transform Infrared Spectroscopy and nano-indentation methods, respectively. Nuclear resonant reaction analysis was used to measure the amount of hydrogen and carbon in the thin films. Furthermore, wettability of the thin films was achieved by measuring of water contact angle (WCA). The results indicated that the structural properties of the diamond-like carbon thin films are strongly dependent on the composition of gas mixture. Based on ellipsometry results, refractive index of the thin films varied in the range of 1.89–2.06 at 550 nm. FTIR results determined that deposition of DLC thin films on silicon substrate led to an increase of the light transmission in IR region and these films have the potential to be used in silicon optics as the antireflective coatings in this region. Nano-indentation analysis showed that the thin films hardness changed in the range of 7.5–11 GPa. On the other hand hydrogen content and fraction of C‒H bonds in the samples increased by an increase in the gas ratio of CH4/Ar. Also, WCA measurements indicated that WCA for thin films with gas ratio of 3/7 is the most and equal to 79°.
Similar content being viewed by others
References
Angus, J.C.: Categorization of dense hydrocarbon films. FMBS Symp. Proc. 17, 179–187 (1987)
Chattopadhyay, S., Huang, Y.F., Jen, Y.J., Ganguly, A., Chen, K.H., Chen, L.C.: Anti-reflecting and photonic nanostructures. Mater. Sci. Eng. 69, 1–35 (2010)
Chen, T.S., Chiou, S.E., Shiue, S.T.: The effect of different radio-frequency powers on characteristics of amorphous boron carbon thin film alloys prepared by reactive radio-frequency plasma enhanced chemical vapor deposition. Thin Solid Films 528, 86–92 (2013)
Cho, C.W., Hong, B., Lee, Y.Z.: Wear life evaluation of diamond-like carbon films deposited by microwave plasma-enhanced CVD and RF plasma-enhanced CVD method. Wear 259, 789–794 (2005)
Choi, W.S., Hong, B.: The effect of annealing on the properties of diamond-like carbon protective antireflection coatings. Renew. Energy 33, 226–231 (2008)
Clay, K.J., Speakman, S.P., Morrison, N.A., Tomozeiu, N., Milne, W.I., Kapoor, A.: Material properties and triboloical performance of rf-PECVD depositrd DLC coatings. Diam. Relat. Mater. 7, 1100–1107 (1998)
Coskun, O.D., Zerrin, T.: Optical, structural and bonding properties of diamond-like amorphous carbon films deposited by DC magnetron sputtering. Diam. Relat. Mater. (2015). https://doi.org/10.1016/j.diamond.2015.04.004
Ferrari, A.C.: Non-destructive Characterisation of Carbon Films, pp. 25–82. Springer, Boston (1996)
Ferrari, A.C., Robertson, J.: Raman spectroscopy of amorphous nanostructured, diamond-like carbon, and nanodiamond. Philos. Trans. R. Soc. Lond. A 362, 2477–2512 (2004)
Ferrari, A.C., Robertson, J., Beghi, M.G., Bottani, C.E., Ferulano, R., Pastorelli, R.: Elastic constants of tetrahedral amorphous carbon films by surface Brillouin scattering. Appl. Phys. Lett. 75, 1893–1895 (1999)
Furlan, K.P., Klein, A.N., Hotza, D.: Diamond like carbon films deposited by hydrocarbon plasma sources. Rev. Adv. Mater. Sci. 34, 165–172 (2013)
Glew, A.D., Saha, R., Kim, J.S., Cappelli, M.A.: Ion energy and momentum flux dependence of diamond-like carbon film synthesis in radio frequency discharges. Surf. Coat. Technol. 114, 224–229 (1999)
Gontar, A.G., Starik, S.P., Tkach, V.M., Gorochov, V.Y., Gorshtein, B.A., Mozkova, O.M.: Application of diamond-like films for improving transparency in the IR. In: Lee, J., Novikov, N., Turkevich, V. (eds.) Innovative Superhard Materials and Sustainable Coatings for Advanced Manufacturing. NATO Science Series II: Mathematics, Physics and Chemistry, vol. 200, pp. 445–453. Springer, Dordrecht (2005)
Grill, A.: Electrical and optical properties of diamond-like carbon. Thin Solid Films 355, 189–193 (1999)
Grill, A., Patel, V.: Diamond like carbon deposited by DC PACVD. Diam. Films Technol. 1, 219–233 (1992)
Harrise, D.C.: Materials for Infrared Windows and Domes Properties and Performance. (pp. 27–28). SPIE, Washington (1999)
Irmer, G., Dorner-Reisel, A.: Micro-Raman studies on DLC coating. Adv. Eng. Mater. 7, 694–705 (2005)
Kadiyala, K.C.: M.Sc.Thesis, India: Nagarjuna University (2006)
Kim, Y.T., Cho, S.M., Choi, W.S., Hong, B., Yoon, D.H.: Dependence of the bonding structure of DLC thin films on the deposition conditions of PECVD method. Surf. Coat. Technol. 169, 291–294 (2003)
Klyui, N.I., Litovchenko, V.G., Kostylyov, V.P., Rozhin, A.G., Gorbulik, V.I., Voronkin, M.A., Zaika, N.I.: Silicon solar cells with antireflecting and protective coatings based on diamond-like carbon and silicon carbide films. Opto Electron. Rev. 8, 406–409 (2000)
Maıtre, N., Girardeau, T.H., Camelio, S., Barranco, A., Vouagner, D., Breelle, E.: Effects of negative low self-bias on hydrogenated amorphous carbon films deposited by PECVD technique. Diam. Relat. Mater. 12, 988–992 (2003)
Merel, P., Tabbal, M., Chaker, M., Moisa, S., Margot, J.: Direct evaluation of the sp(3) content in diamond-like-carbon films by XPS. Appl. Surf. Sci. 136, 105–110 (1998)
Nickolai I.K., Anatoliy N.L., Anatoliy V.M., Volodymyr B.L., Gennadiy S.Kh., Andriy N.K.: Improvement of solar cells efficiency and radiation stability by deposition of diamond-like carbon films. World Renew. Energy. Congress–Sweden. 11, 2787–2794 (2011)
Oliveira, M.H., Silva, D.S., Cortes, A.D.S., Namani, M.A.B., Marques, F.C.: Diamond like carbon used as antireflective coating on crystalline silicon solar cells. Diam. Relat. Mater. 18, 1028–1030 (2009)
Oliver, W.C., Pharr, G.M.: An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564–1573 (1992)
Reddy, K.N., Varade, A., Krishna, A., Joshua, J., Sasen, D., Chellamalai, M.: Double side coating of DLC on silicon by RF-PECVD for AR application. Procedia Eng. 97, 1416–1421 (2014)
Robertson, J.: Amorphous carbon. Adv. Phys. 35, 317–374 (1986)
Robertson, J.: Electronic structure and bonding of aC: H. In: Proceedings of Materials Science Forum (1990)
Robertson, J.: Hard amorphous (diamond-like) carbon. Prog. Solid State Chem. 21, 199–333 (1991)
Robertson, J.: Mechanical properties and coordinations of amorphous carbons. Phys. Rev. Lett. 68, 220–223 (1992)
Robertson, J.: Diamond-like amorphous carbon. Mater. Sci. Eng., R 37, 129–281 (2002)
Robertson, J.: Electronic and atomic structure of diamond-like carbon. Semicond. Sci. Technol. 18, S12–S19 (2003)
Ronkainen, H.: Tribological properties of hydrogen and hydrogen-free diamond-like carbon coating. Technical Research center of Finland Valtion Teknillinen Tutkimuskeskus (2001)
Safaie, P., Eshaghi, A., Bakhshi, S.R.: Oxygen doping effect on the wettability of diamond-like carbon thin films. J. Non Cryst. Solids 471, 410–414 (2017). https://doi.org/10.1016/j.jnoncrysol.2017.06.034
Schwan, J., Ulrich, S., Batori, V., Ehrhardt, H., Silva, S.R.P.: Raman spectroscopy on amorphous carbon films. J. Appl. Phys. 80, 440–447 (1996)
Singh, S.M., Pandey, M., Kishore, R.: Influence of impinging ion energy on the bonding and mechanical characteristics of DLC films deposited by microwave ECR plasma CVD. Plasma Process. Polym. 5, 853–860 (2008)
Siraj, K., Khaleeq-Rahman, M., Rafique, M.S., Munawar, M.Z., Naseem, S., Riaz, S.: Pulsed laser deposition and characterization of multilayer metal-carbon thin films. Appl. Surf. Sci. 257, 6445–6450 (2011)
Smietana, M., Szmidt, J., Korwin-Pawlowski, M.L., Miller, N., Elmustafa, A.A.: Influence of RF PACVD process parameters of diamond-like carbon films on optical properties and. nano-hardness of the films. Diam. Relat. Mater. 17, 1655–1659 (2008)
Tauc, J., Grigorovici, R., Vancu, A.: Optical properties and electronic structure of amorphous Germanium. Phys. Status Solidi B 15, 627–637 (1966)
Varade, A., Reddy, K.N., Sasen, D., Krishna, A., Chellamalai, M., Shashikumar, P.V.: Detailed Raman study of DLC coating on Si (100) made by RFPECVD. Procedia Eng. 97, 1452–1456 (2014)
Wang, J., Li, W.Z.: Influence of the bombardment energy of CHn+ ions on the properties of diamond-like carbon films. Surf. Coat. Technol. 122, 273–276 (1999)
Yao, L., He, J.: Recent progress in antireflection and self-cleaning technology—from surface engineering to functional surfaces. Prog. Mater Sci. 61, 94–143 (2014)
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Samadi, M., Eshaghi, A., Bakhshi, S.R. et al. The influence of gas flow rate on the structural, mechanical, optical and wettability of diamond-like carbon thin films. Opt Quant Electron 50, 193 (2018). https://doi.org/10.1007/s11082-018-1456-6
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s11082-018-1456-6