3D/2.5D IC-Based Obfuscation

Device scaling has increased interconnect power and delay to an extent that it is presenting a bottleneck to further performance gain. 3D/2.5D integration technology emerges as a viable option to improve chip performance in a direction orthogonal to costly device scaling. While the technology was originally proposed to enhance performance, it has unlocked new opportunities to thwart security threats in a global IC supply chain. Various obfuscation techniques based on 3D/2.5D IC technology have been proposed to protect IC designs from being pirated or tampered during outsourced fabrication. This chapter presents the current state of 3D/2.5D IC-based obfuscation techniques and highlights potential security opportunities and challenges of this technology in hardware intellectual property (IP) protection.