Quantifying improvements in adhesion of platinum films on brittle substrates

This study used nanoindentation coupled with stressed overlayers to evaluate the effect of titanium interlayers on the interfacial fracture energy of platinum films on SiO₂substrates. Interfacial fracture energy was calculated three ways: from platinum buckles that formed spontaneously upon deposition of the film, from buckles that formed upon deposition of a stressed tungsten overlayer, and from blisters triggered by indentation of a platinum film with a tungsten stressed overlayer. The calculated values for the interfacial fracture energy of the Pt-SiO₂interface were 0.2 and 0.5 J/m²for indentation blisters and spontaneous buckles, respectively. The effect of a titanium interlayer on adhesion was examined using a tungsten stressed overlayer coupled with nanoindentation. The addition of a titanium layer improved the adhesion of the platinum film on SiO₂from 0.2 to 1.0 J/m².