Mechanical strength assessment of very thin films for optical and electronic applications

A micro scratch device for testing very thin optical and electronic coatings is presented. Owing to a down-scaled diamond indenter tip radius (2 mu m) and appropriate load range, coating and interface specific strength data can be assessed. Two case studies are presented: the first on the influence of the interface quality of W coatings on silicon wafers as modified by ion-beam techniques (post-implantation and ion-beam assisted deposition); the second on the influence of substrate nature and surface cleaning of flat glass prior to deposition of a magnetron sputtered Ni-Cr PVD coating. (C) 1997 Elsevier Science S.A.