International Business Machines Corporation
Secure wafer inspection and identification

Abstract:

Techniques for secure and tamper-resistant wafer identification using a unique wafer fingerprint are provided. In one aspect, a method for wafer authentication includes: placing, at each level of fabrication of chips on the wafer, reference structures across the chips; inspecting the wafer at each level of the fabrication; and performing at least one of overlay and scatterometry measurements of the reference structures to use as a unique fingerprint for authenticating the wafer that has been inspected. A method for authentication throughout a process flow for fabrication of chips on a wafer is also provided, as is a wafer having chips and reference structures placed across the chips at each level of the chips to provide a unique fingerprint for authenticating the wafer.