Tenacious Hardware Trojans Due to High Temperature in Middle Tiers of 3-D ICs

Hardware security is a major concern in the intellectual property (IP) centric integrated circuits (IC). 3-D IC design augments IP centric designs. However, 3-D ICs suffer from high temperatures in their middle tiers due to long heat dissipation paths. We anticipate that this problem would exacerbate the hardware security issues in 3-D ICs. Because, high temperature leads to undesired timing characteristics in ICs. In this paper we provide a detailed analysis on how these delay variations can lead to non-ideal behavior of control paths. It is demonstrated that a hardware intruder can leverage this phenomenon to trigger the payload, without requiring a separate triggering circuit. Our simulation results show that a state machine can lead to temporary glitches long enough to cause malfunctioning at temperatures of 87 degrees C or above, under nominal frequencies. The overall area overhead of the payload compared to a very small Mod-3 counter is 6%.