Patent ID: 10347591

Abstract:
A metallic, stress-tunable thin film structure is applied to the backside of an epitaxial wafer to compensate for stress created by the frontside epitaxial layers. The structure may comprise multiple layers, including a metallic stress compensation layer (“SCL”), a metallic adhesive layer and/or a passivation (or solder attach) layer. In other embodiments, the stress compensation structure comprises only the metallic stress compensation layer. In a first application, the metallic stress compensation structure is applied to a backside of an epitaxial wafer prior to beginning device fabrication, correcting for bow present in as-purchased wafers. In a second application, the metallic stress compensation structure is applied to a backside of a thinned epitaxial wafer at the completion of frontside processing, preventing bow-induced wafer breakage upon removal from the rigid support structure or carrier disc.