Sensitivity to Laser Fault Injection: CMOS FD-SOI vs. CMOS Bulk

Integrated circuits (ICs) laser illumination was originally used for emulation of radioactive ionizing particles effects on devices. Today, it is also a means for injecting faults into the computations of secure ICs for the purpose of retrieving secret data. The CMOS FD-SOI technology is expected to be less sensitive to laser fault injection than the more usual CMOS bulk technology. We report in this paper an experimental assessment of the interest of using FD-SOI rather than CMOS bulk to decrease laser sensitivity. Our experiments were conducted on test chips at the 28 nm node for both technologies with laser pulse durations in the picosecond and nanosecond ranges. We also discuss the interest of using bulk current sensors along with FD-SOI technology to achieve optimal detection of laser fault injection attempts.