Considerations for Bond Strength Metrology and Standards

Chevron based bond strength structures provide significant advantages over the double cantilever beam method commonly in use. We introduce new bond strength test structure designs with the goal of simplifying the implementation of the chevron test and improving the availability of bond strength metrology. We describe designs based on chip-to-chip bonding which could be expanded to chip to wafer. There are both asymmetric bond structures based on separate designs for the top and bottom chips and symmetric designs in which the same chip design serves as both top and bottom. We describe a fabrication process which is compatible with both blanket dielectric and metal bonding surfaces as well as patterned surfaces including hybrid bonding type materials. We also describe a testing apparatus and the potential to adapt commercial die shear testers for this measurement. Finally, we describe a plan to realize research grade test materials based on these test structures.