3-D Extensions for Trustworthy Systems

Trustworthy system development entails a high nonrecurring engineering (NRE) cost together with a low volume of units over which to amortize that cost. For example, the potential for developmental and operational attacks against hardware requires countermeasures that make it very expensive to design and manufacture custom hardware used to build high assurance systems. To address these problems, we propose an approach to trustworthy system development based on 3-D integration, an emerging chip fabrication technique in which two or more integrated circuit dies are fabricated individually and then combined into a single stack using vertical conductive posts. With 3-D integration, a generalpurpose die, or computation plane, can be combined with a special-purpose die, or control plane. We discuss the security advantages of using 3-D integrated hardware in sensitive applications, where security is of the utmost importance, and we outline problems, challenges, attacks, solutions, and topics for future research.