Mechanical stability of multilayer coatings
Un article de Surface du verre et interfaces.
Etienne Barthel - Davy Dalmas - Xuan Geng (PhD 2005-2008)
Thin multilayer coatings are widely used to modify the optical or thermal properties of glass, such as solar control, thermal isolation and anti-reflection. These coatings consist of oxides, nirides and metal layers. Silver is often used for its specific dielectric response in the visible range. Silver however, which belongs to the group of non-reactive metals, forms an abrupt interface with all oxides without formation of interphase. The resulting adhesion energies are low: this will threaten the mechanical stability of the coating during processing or service. One of the resulting issues is the sensitivity to scratch damage.
In practice, the scratches have well-defined features: flat groove, straight edges and constant width. The scratch behaviors reflect the contrast in bulk or suface properties of the coating material as well as interfacial properties of the multilayered structure.
Collaborations
Z. Zhang, AMD, San Jose, USA.