Abstract
Molecular organization of self-assembled n-dimethyl-n-octadecyl-3-aminopropyltrimethoxysilychloride (DMOAP) layers on indium tin oxide (ITO) coated glass substrates was thoroughly investigated. The layer thickness for each deposition was determined by variable angle spectroscopic ellipsometry (VASE), while from static contact-angle measurements we deduced valuable information regarding the ordering of the molecular structures at the solid-air interface. In particular, the DMOAP thin film formation was studied for two different drying temperatures (85 °C and 120 °C). While at Tdrying = 85 °C we observed the formation of a molecular monolayer characterized by a close packed structure, at the higher temperature the DMOAP molecules “bend” at the substrate as they stack in relatively disordered clusters. A qualitative interpretation of this phenomenon is given, in good agreement both with the obtained experimental data and experimental investigation reported in the scientific literature. The observations regarding the DMOAP molecular level organization as a function of substrate temperature could bring essential information to the self assembly research community and also explain some important physical phenomena occurring at interfaces.
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References
M.C. Petty: Langmuir-Blodgett Films. An Introduction (–Cam-bridge University Press, Cambridge, UK, 1996).
A. Ulman: An Introduction to Ultrathin Organic Films from Langmuir-Blodgett to Self-Assembly (Academic Press, San Diego, CA, 1991).
L.M. Blinov and V.G. Chigrinov: ElectroOptic Effects in Liquid Crystal Materials (Springer-Verlag, New York, 1994).
J.H. Huang, R. Superfine and Y.R. Shen: Nonlinear spectroscopic study of coadsorbed liquid-crystal and surfactant monolayers: Conformation and interaction. Phys. Rev. A 42(6), 3660 (1990)
R.A. Drawhorn and N.L. Abbott: Anchoring of nematic liquid crystals on self-assembled monolayers formed from alkanethiols on semitransparent films of gold. J. Phys. Chem. 99, 16511 (1995)
J.G. Fonseca, J. Hommet and Y. Galerne: Surface structure and anchoring properties of modified self-assembled monolayers. Appl. Phys. Lett. 82(1), 58 (2003)
J.C. Huie: Guided molecular self-assembly: A review of recent efforts. Smart Mater. Struct. 12, 264 (2003)
R.K. Smith, P.A. Lewis and P.S. Weiss: Review—Patterning self-assembled monolayers. Prog. Surf. Sci. 75, 1 (2004)
M.E. Anderson, C. Srnivasan, J.N. Hohman, E.M. Carter, M.W. Horn and P.S. Weiss: Combining conventional lithography with molecular self-assembly for chemical patterning. Adv. Mater. 18, 3258 (2006)
A. Ulman: Formation and structure of self-assembled mono-layers. Chem. Rev. 96, 1533 (1996)
W.C. Bigelow, D.L. Pickett and W.A. Zisman: Oleophobic monolayers I. Films adsorbed from solution in non-polar liquids. J. Colloid Sci. 1, 513 (1946)
A. Nakajima, K. Hashimoto, T. Watanabe, K. Takai, G. Yamauchi and A. Fujishima: Transparent superhydrophobic thin films with self-cleaning properties. Langmuir 16, 7044 (2000)
J.B. Brzoska, N. Shahidzadeh and F. Rondelez: Evidence of a transition temperature for the optimum deposition of grafted monolayer coatings. Nature 360, 719 (1992)
M.E. McGovern, K.M.R. Kallury and M. Thompson: Role of solvent on the silanization of glass with octadecyltrichlorosilane. Langmuir 10, 3607 (1994)
P. Silberzan, L. Léger, D. Ausserré and J.J. Benattar: Silanation of silica surfaces. A new method of constructing pure or mixed monolayers. Langmuir 7, 1647 (1991)
J.B. Brzoska, I.B. Azouz and F. Rondelez: Silanization of solid substrates: A step toward reproducibility. Langmuir 10, 4367 (1994)
Y. Liu, L.K. Wolf and M.C. Messmer: A study of alkyl chain conformational changes in self-assembled n-octadecyltrichlorosi-lane monolayers on fused silica surfaces. Langmuir 17, 4329 (2001)
J.V. Davidovits, V. Pho, P. Silberzan and M. Goldmann: Temperature influence on the formation of silanized monolayers on silica: An atomic force microscopy study. Surf. Sci. 352–354, 369 (1996)
A.Y. Fadeev and T.J. McCarthy: Self-assembly is not the only reaction between alkyltrichlorosilanes and surfaces: Monomolecular and oligomeric covalently attached layers of dichloro and trichloroalkylsilanes on silicon. Langmuir 16, 7268 (2000)
I. Lelidis and C. Oedman: Influence of substrate nature and growth conditions on the morphology of thin DMOAP films. Liq. Cryst. 30(6), 643 (2003)
V.K. Gupta and N.L. Abbot: Azimuthal anchoring transition of nematic liquid crystals on self-assembled monolayers formed from odd and even alkanethiols. Phys. Rev. E 54(5), R4540 (1996).
C. Vena, C. Versace, G. Strangi, S. DéElia and R. Bartolino: Light depolarization effects during Fréedericksz transition. Opt. Express 15(25), 17063 (2007)
C.D. Bain, E.B. Troughton, T. Yu-Tai, J. Evall, G.M. Whitesides and R.G. Nuzzo: Formation of monolayer films by the spontaneous assembly of organic thiols from solution onto gold. J. Am. Chem. Soc. 111, 321 (1989)
A.M. Almanza-Workman, S. Raghavan, S. Petrovic, B. Gogoi, P. Deymier, D.J. Monk and R. Roop: Characterization of highly hydrophobic coatings deposited onto pre-oxidized silicon from water dispersible organosilanes. Thin Solid Films 423, 77 (2003)
P.G. de Gennes: Wetting: Static and dynamics. Rev. Mod. Phys. 57(3) (1985).
E.L. Decker and S. Garoff: Contact line structure and dynamics on surfaces with contact angle hysteresis. Langmuir 13, 6321 (1997)
A.B.D. Cassie: Contact angles. Discuss. Faraday Soc. 75, 5041 (1952)
J.N. Israelachvili and M.L. Gee: Contact angles on chemically heterogeneous surfaces. Langmuir 5, 288 (1989)
Genell Med auf Floarglas—Balzers Thin Films Prod: ID. BD051149, BATCH 1400-655-(1999).
S. DéElia, M. Castriota, A. Policicchio, C. Versace, N. Scaramuzza, R.G. Agostino, E. Cazzanelli, C. Vena, G. Strangi and R. Bartolino: Thermally induced modifications of the optic properties of lead zirconate titanate thin films obtained on different substrates by sol-gel synthesis. J. Appl. Phys. 104, 123522 (2008)
S. DéElia, F. Ciuchi, C. Versace, N. Scaramuzza, G. Strangi and R. Bartolino: Ellipsometry investigation of the effects of annealing temperature on the optical properties of indium tin oxide thin films studied by Drude-Lorentz model. App. Surf. Sci., 255(16), 7203 (2009)
H.G. Tompkins and E.A. Irene: Handbook of Ellipsometry (Springer, Berlin, 2005).
D.E. Aspnes: Optical properties of thin films. Thin Solid Films 89, 249 (1982)
R.M.A. Azzam and N.M. Bashara: Ellipsometry and Polarized Light (North-Holland, Amsterdam, 1992).
H. Hillebrant and M. Tanoka: Electrochemical characterization of self-assembled alkylsiloxane monolayers on indium-tin oxide (ITO) semiconductor electrodes. J. Phys. Chem. B 105, 4270 (2001)
S.A. Kulinich and M. Farzaneh: Alkylsilane self-assembled monolayers: Modelling their wetting characteristics. Appl. Surf. Sci. 230, 232 (2004)
M. Miyama, Y. Yang, T. Yasuda, T. Okuno and H.K. Yasuda: Static and dynamic contact angles of water on polymeric surfaces. Langmuir 13, 5494 (1997)
S. Seki, T. Aoyama, Y. Sawada, M. Ogawa, M. Sano, N. Miyabayashi, H. Yoshida, Y. Hoshi, M. Ide and A. Shida: Evolution of water vapor from indium-tin-oxide thin films fabricated by various deposition processes. J. Therm. Anal. Calorim. 69, 1021 (2002)
Y. Sawada, S. Seki, M. Sano, N. Miyabayashi, K. Ninomiya, A. Iwasawa, T. Tsugashi, R. Ozao and Y. Nishimoto: Evolution of water vapor from indium-tin-oxide transparent conducting films fabricated by the dip coating process. J. Therm. Anal. Calorim. 77, 751 (2004)
I.A. Ryzhikov, A.A. Pukhov, A.S. Iléin, N.P. Glukhova, K.N. Afanasiev and A.S. Ryzhikov: Anomalous temperature dependence of the conductivity of nanoporous ITO films. Microelectron. Eng. 69, 270 (2003)
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D’Elia, S., Barna, V., Scaramuzza, N. et al. The influence of drying temperature on the close packed structure of silanized monolayers deposited on indium tin oxide (ITO) substrates. Journal of Materials Research 24, 2784–2794 (2009). https://doi.org/10.1557/jmr.2009.0337
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DOI: https://doi.org/10.1557/jmr.2009.0337