BRDF characterization of Al-coated thermoplastic polymer surfaces


In this paper, we present a combined morphological and optical characterization of aluminum-coated thermoplastic polymer surfaces. Flat plastic substrates, obtained by means of an injection molding process starting from plastic granules, were coated with ultra-thin aluminum films evaporated in vacuo, on top of which a silicon-based protective layer was plasma deposited in order to prevent oxidation of the metal reflective surface. Different sample treatments were studied to unravel the influence of substrate chemistry, substrate thickness, aluminum and protective layer thickness, and surface roughness on the actual optical reflectance properties. Bidirectional reflectance distribution function measurements, corroborated by surface morphological information obtained by means of atomic force microscopy, correlate reflectance characteristics with the root-mean-square surface roughness, providing evidence for the role of the substrate and the thin films’ morphology. The results unravel information of interest within many applicative fields involving metal coating processes of plastic substrates as an example in the case of automotive lighting.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11


  1. 1.

    Carraro, C, Maboudian, R, Magagnin, L, “Metallization and Nanostructuring of Semiconductor Surfaces by Galvanic Displacement Processes.” Surf. Sci. Rep., 62 499–525 (2007)

    CAS  Article  Google Scholar 

  2. 2.

    Richter, J, Seidel, R, Kirsch, R, Mertig, M, Pompe, W, Plaschke, J, Schackert, HK, “Nanoscale Palladium Metallization of DNA.” Adv. Mater., 12 507–510 (2000)

    CAS  Article  Google Scholar 

  3. 3.

    Parbukov, AN, Beklemyshev, VI, Gontar, VM, Makhonin, II, Gavrilov, SA, Bayliss, SC, “The Production of a Novel Stain-Etched Porous Silicon, Metallization of the Porous Surface and Application in Hydrocarbon Sensors.” Mater. Sci. Eng. C. Mater. Biol. Appl. C, 15 121–123 (2001)

  4. 4.

    Josell, D, Burkhard, C, Li, Y, Cheng, YW, Keller, RR, Witt, CA, Kelley, DR, Bonevich, JE, Baker, BC, Moffat, TP, “Electrical Properties of Superfilled Sub-micrometer Silver Metallizations.” J. Appl. Phys., 96 759–768 (2004)

    CAS  Article  Google Scholar 

  5. 5.

    Sharma, RK, Geyer, HJ, Mitchell, DG, “Metallization Scheme Providing Adhesion and Barrier Properties.” US Patent 4,927,505, 1990

  6. 6.

    Papavinasam, S, Attard, M, Arseneult, B, Revie, RW, “State-of-the-Art of Thermal Spray Coatings for Corrosion Protection.” Corr. Rev., 26 105–145 (2008)

    CAS  Google Scholar 

  7. 7.

    Kim, HC, Alford, TL, “Improvement of the Thermal Stability of Silver Metallization.” J. Appl. Phys., 94 5393–5395 (2003)

    CAS  Article  Google Scholar 

  8. 8.

    Wu, Z, Wu, D, Qi, S, Zhang, T, Jin, R, “Preparation of Surface Conductive and Highly Reflective Silvered Polyimide Films by Surface Modification and In Situ Self-metallization Technique.” Thin Solid Films, 493 179–184 (2005)

    CAS  Article  Google Scholar 

  9. 9.

    Hao, Y, Sim, PC, Toner, B, Frank, M, Ackermann, M, Tan, A, Kuniss, U, Kho, E, Doblaski, J, Hee, EG, Hoelke, A, Wada, S, Oshima, T, Liew, M, “A 0.18 μm SOI BCD Technology for Automotive Application.” 27th International Symposium on Power Semiconductor Devices & IC’s (ISPSD), Hong Kong, May 2015

  10. 10.

    Kilian, A, Schmidt, LP, “A Novel Fabrication Process for Printed Antennas Integrated in Polymer Multi-layer Car Body Panels.” 2009 European Microwave Conference (EuMC), Rome, September 2009

  11. 11.

    Mattox, DM, Handbook of Physical Vapor Deposition (PVD) Processing. William Andrew, Burlington (2010)

    Google Scholar 

  12. 12.

    Wang, J, Huang, H, Kesapragada, SV, Gall, D, “Growth of Y-Shaped Nanorods Through Physical Vapor Deposition.” Nano Lett., 5 2505–2508 (2005)

    CAS  Article  Google Scholar 

  13. 13.

    Richter, G, Hillerich, K, Gianola, DS, Monig, R, Kraft, O, Volkert, CA, “Ultrahigh Strength Single Crystalline Nanowhiskers Grown by Physical Vapor Deposition.” Nano Lett., 9 3048–3052 (2009)

    CAS  Article  Google Scholar 

  14. 14.

    Sproul, WD, “Physical Vapor Deposition Tool Coatings.” Surf. Coat. Technol., 81 1–7 (1996)

    CAS  Article  Google Scholar 

  15. 15.

    Nicodemus, FE, Richmond, JC, Hsia, JJ, “Geometrical Considerations and Nomenclature for Reflectance.” US Department of Commerce, National Bureau of Standards, 160 (1977)

  16. 16.

    Leloup, FB, Forment, S, Dutré, P, Pointer, MR, Hanselaer, P, “Design of an Instrument for Measuring the Spectral Bidirectional Scatter Distribution Function.” Appl. Opt., 47 5454–5467 (2008)

    Article  Google Scholar 

  17. 17.

    ASTM E2387-19, Standard Practice for Goniometric Optical Scatter Measurements, ASTM International, West Conshohocken, PA, 2019

  18. 18.

    Haugstad, G, Atomic Force Microscopy: Understanding Basic Modes and Advanced Applications. Wiley, Hoboken (2012)

    Google Scholar 

  19. 19.

    Nečas, D, Klapetek, P, “Gwyddion: An Open-Source Software for SPM Data Analysis.” Cent. Eur. J. Phys., 10 181–188 (2012)

    Google Scholar 

  20. 20.

    Granier, A, Vervloet, M, Aumaille, K, Vallée, C, “Optical Emission Spectra of TEOS and HMDSO Derived Plasmas Used for Thin Film Deposition.” Plasma Sources Sci. Technol., 12 89 (2003)

    CAS  Article  Google Scholar 

  21. 21.

    Gosar, Ž, Kovač, J, Mozetič, M, Primc, G, Vesel, A, “Characterization of Gaseous Plasma Sustained in Mixtures of HMDSO and O2 in an Industrial-Scale Reactor.” Plasma Chem. Plasma Proc., 40 25–42 (2020)

    CAS  Article  Google Scholar 

  22. 22.

    Bruckman, LS, Murray, MP, Richardson, S, Brown, SA, Schuetz, MA, French, RH, Degradation of Back Surface Acrylic Mirrors: Implications for Low Concentration and Mirror Augmented Photovoltaics. IEEE EnergyTech, Cleveland, OH (2012)

    Google Scholar 

  23. 23.

    Bernacki, BE, Johnson, TJ, Myers, TL, Blake, TA, “Modeling Liquid Organic Thin Films on Substrates.” Chemical, Biological, Radiological, Nuclear, and Explosives (CBRNE) Sensing XIX. International Society for Optics and Photonics, Orlando, FL, May 2018

  24. 24.

    Freniere, ER, Gregory, GG, Chase, RC, “Interactive Software for Optomechanical Modeling.” Lens Design, Illumination, and Optomechanical Modeling, International Society for Optics and Photonics, San Diego, CA, September 1997

  25. 25.

    Harvey, JE, “Light-Scattering Characteristics of Optical Surfaces.” Stray Light Problems in Optical Systems, International Society for Optics and Photonics, Reston, VA, September 1977

  26. 26.

    Audenaert, J, Leloup, FB, Durinck, G, Deconinck, G, Hanselaer, P, “Bayesian Deconvolution Method Applied to Experimental Bidirectional Transmittance Distribution Functions.” Meas. Sci. Technol., 24 035202 (2013)

    CAS  Article  Google Scholar 

  27. 27.

    Harvey, JE, Choi, N, Schroeder, S, Duparré, A, “Total Integrated Scatter from Surfaces with Arbitrary Roughness, Correlation Widths, and Incident Angles.” Opt. Eng., 51 013402 (2012)

    Article  Google Scholar 

  28. 28.

    Hass, G, Hunter, WR, Tousey, R, “Reflectance of Evaporated Aluminum in the Vacuum Ultraviolet.” J. Opt. Soc. Am., 46 1009–1012 (1956)

    CAS  Article  Google Scholar 

  29. 29.

    Karoui, A, “Aluminum Ultra Thin Film Grown by Physical Vapor Deposition for Solar Cell Electric Nanocontacts.” ECS Transactions, 41 21–28 (2011)

    CAS  Article  Google Scholar 

  30. 30.

    Schmauder, T, Sauer, P, Ickes G, “New Reflectors and Reflector Coaters.” In 57th Annual Technical Conference Proceeding of the Society of Vacuum Coaters, Chicago, IL, May 2014

  31. 31.

    Schmauder, T, Küper, S, Wohlfahrt, P, “High Reflective Silver Coatings on 3D Plastic Parts for Solar Concentrators.” In 52nd Annual Technical Conference Proceedings of SVC, Santa Clara, CA, May 2009

Download references


TF, IP, VL, and EV acknowledge financial support from UniTs and Marelli Automotive Lighting Italy through the project “Caratterizzazione sperimentale e/o numerica delle proprietà ottiche ed elettroniche di materiali da impiegare per la generazione e la focalizzazione di fasci di luce con lo scopo di sviluppare nuovi sistemi ottici per il settore automotive”.

Author information



Corresponding authors

Correspondence to Erik Vesselli or Frédéric B. Leloup.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Fontanot, T., Audenaert, J., Hanselaer, P. et al. BRDF characterization of Al-coated thermoplastic polymer surfaces. J Coat Technol Res (2020).

Download citation


  • BRDF
  • Aluminum coating
  • Thin film
  • AFM
  • Surface roughness