An Experimentally Tuned Compact Electrical Model for Laser Fault Injection Simulation

Abstract

This work reports LFI experiments carried out on custom CMOS 65 nm digital test gates, aiming at tuning the parameters of a compact electrical model. Like in previous works, we observed a difference in behavior in the induced faults when using nanosecond and picosecond range laser pulse duration. However, our experimental results showed that the laser-sensitive areas were restricted to the PMOS transistors for ns laser pulses, contrary to what was previously stated in the literature. For ps pulse duration, these works outline the sensitivity of both the NMOS and PMOS of an SRAM cell following the theoretical model of LFI. These experiments help to calibrate the parameters of a compact electrical model, allowing the simulation of LFI attacks (using SPICE-like CAD tools). This compact model is built upon previous works, with simplifications to facilitate its use. Once tuned, simulations using the proposed compact model exhibit a good correlation with the experimental results.