Sacrificial buffer layer for metal removal at a bevel edge of a substrate

Abstract

A method of forming a semiconductor structure includes forming a dielectric layer surrounding contacts over a top surface and bevel edge of a substrate, forming a sacrificial buffer layer over the dielectric layer, removing portions of the sacrificial buffer layer formed over the dielectric layer on the top surface of the substrate, and patterning device structures including one or more metal layers over the contacts, wherein patterning the device structures removes portions of the metal layers formed over the top surface of the substrate leaving the metal layers on the bevel edge. The method also includes forming an encapsulation layer and performing a bevel dry etch to remove the encapsulation layer and the metal layers on the bevel edge. The bevel dry etch damages the sacrificial buffer layer on the bevel edge underneath the metal layers. The method further includes removing the damaged sacrificial buffer layer from the bevel edge.