Interface fracture and chemistry of a tungsten-based metallization on borophosphosilicate glass
In microelectronic devices, the interface between barrier metal and dielectric is of particular interest for a reliable electronic functionality. However, it is frequently observed that this interface is prone to failure. In this work, the strength of interfaces between an as-deposited borophosphosilicate dielectric glass (BPSG) layer and a W(Ti) metallization with and without Ti interlayer was the centre of interest. Four-point-bending tests were used for the mechanical characterization combined with a topological and chemical analysis of the fracture surfaces. In addition, the interface chemistry was studied locally prior to the testing to search for a possible Ti enrichment at the interface. The fracture results will be discussed taking the chemical and topological information into account.