Combinatorial Materials Design Approach to Investigate Adhesion Layer Chemistry for Optimal Interfacial Adhesion Strength

A combinatorial material adhesion study was used to optimize the composition of an promoting layer for a nanocrystalline diamond (NCD) coating on silicon. Three different metals, namely W, Cr, and Ta, were selected fabricate arrays co-sputtered binary alloy films, with patches seven different, distinct compositions each combination, single element reference films Si wafer (three wafers in total; W–Cr, Cr–Ta, Ta–W). Scratch testing determine critical failure load practical work NCD coatings as function chemistry. All tested samples eventually exhibit delamination coating, buckles radiating perpendicularly away from scratch track. Application any presented layers yields increase compared Si. While influence maximum buckle length is less pronounced, shorter are obtained pure W Cr–Ta layers. As general rule, addition showed 75% improvement measured energies without layer, specific alloys showing up 125% calculated adhesion.