Embedded Mechanical Interlock into the Silver Plating Layer for Robust Epoxy Molding Compound-To-Carrier Adhesion

Leadless semiconductor package with mechanical interlock is achieved by using a carrier with Cu base material, with selectively plated Ag layer on the leads and the pad. An embedded interlock on the plated layer is introduced, through masking, such that the center of the groove is filled with the plated material or have an enclosed exposed base material surface. The groove/dimple offers a mechanical interlock feature between the exposed Cu base material and/or the plated layer surface, resulting in a stronger adhesion of the epoxy molding compound (EMC) thereby preventing the occurrence of delamination.