US Patent 11056448 Covert gates to protect gate-level semiconductors

Integrated circuit (IC) camouflaging has emerged as a promising solution for protecting semiconductor intellectual property (IP) against reverse engineering. The cell camouflaging covert gate leverages doping and dummy contacts to create camouflaged cells that are indistinguishable from regular standard cells under modern imaging techniques. A comprehensive security analysis of the covert gate shows that it achieves high resiliency against SAT and test-based attacks at very low overheads. Models are derived to characterize the covert cells, and metrics are developed to incorporate them into a gate-level design. Simulation results of overheads and attacks are presented on benchmark circuits.