Glass, surfaces and thin films

Glass and thin film surfaces, interfaces and nanostructures: understanding processes, physico-chemical interactions, multicomponent diffusion and microstructure towards the design of new materials and products with new functionalities.

  • Glass thin film crystallization, optical microscopy. © B. Bouteille

One of Saint-Gobain’s main activities is related to glass products. Most of the functionalized glazings produced by Saint-Gobain is composed by a thin-layer stack deposited onto a flat glass substrate. Phenomena occurring during the deposition process (typically magnetron sputtering) or during subsequent treatments, involving the thin films but also the glass itself, are of great interest since they influence the performance of glazings (optics, durability …).

At SVI we study glasses and coatings starting from their fabrication to the final properties of the materials. We are especially interested in processes, such as liquid-based-deposition, sputtering of thin films, glass melting, and phase separation, but also heat and laser treatment. We explore the atom mobility in complex heterogeneous structures, such as the glass bulk and surface, amorphous and polycristalline thin films and stacks by developing a multicomponent approach. We investigate the growth and microstructure of sputtered metal, oxide and nitride thin films and stacks. Other subjects like phase separation and photocatalysis are also actively investigated.

Our goal is to establish the link between the phenomena occurring during the process and the final properties of the material (bulk or layer).

Our most recent activities in this area cover the following topics:

THIN FILMS ON GLASS

  • Management of Ag layer microstructure and properties (from continuous to nanostructured layers)
  • Study of sputtered layers and stacks (metals – Ag, Ti, NiCr – oxydes – SiO2, ZnO, AZO, TiO2 and nitrides – SiNx)
  • Post-treatment of thin films (cristallization and diffusion)
  • Photocatalysis (TiO2)

INTERFACES AND SURFACES

  • Physico-chemical interactions between coatings and with the substrate (during deposition or post-treatment)
  • Surface of float glass: composition gradient, redox and evolution (corrosion)

SILICATE-BASED MATERIALS

  • Phase separation in thin layers of BaO-B2O3-SiO2
  • Multicomponent diffusion in glass melt (such as the Na2O-CaO–Al2O3–SiO2 system)
  • Mobility at the interface between glass and silica thin layers (obtained by sputter or wet-process)

See also in «Research»

Advanced tools and characterization methods Our activities are supported by advanced Raman spectroscopy, in-situ XPS, real-time characterization of sputtered materials, BRDF, AFM with hot plate, ... Optical properties of structured surfaces Optical properties of micro and nano-structured media (nanoparticles, thin films, patterned surfaces, heterogeneities): link between process parameters and morphological and optical properties of complex media. Laser induced heat propagation in thin film and substrates. Soft matter, liquid films, mixing granular materials Develop fundamental knowledge and tools on the behaviour of multiphase systems involved in the processes of building materials, and on the dynamics of liquids and suspensions used in wet coatings processes