Via disguise to protect the security product from delayering and graphic design system (GDS) hacking and method for producing the same

摘要

A method of forming a stop layer to prevent dummy vias from connecting to a metal layer and the resulting device are provided. Embodiments include forming a first metal layer in a first dielectric layer; forming a second dielectric layer over a first Nblok layer formed over the first dielectric and first metal layers; forming a third dielectric layer over the second dielectric layer and a second Nblok layer formed over a portion of the second dielectric layer; forming a via and a plurality of vias through the third and second dielectric layers down to the second and first Nblok layers, respectively; removing portions of the second and first Nblok layers through the via and the plurality of vias down to the second dielectric layer and the first metal layer, respectively; removing portions of the third dielectric layer through each via; and filling each via with a second metal layer.