ProtFe: Low-Cost Secure Power Side-Channel Protection for General and Custom FeFET-Based Memories

Ferroelectric Field Effect Transistors (FeFETs) have spurred increasing interest in both memories and computing applications, thanks to their CMOS compatibility, low-power operation, and high scalability. However, new security threats to the FeFET-based memories also arise. A major threat is the power analysis side-channel attack (P-SCA), which exploits the power traces of the memory access to obtain data information. There have been several effective efforts on resistive nonvolatile memories (NVMs), but they fail to meet the requirements for secure FeFET-based memories due to the different capacitive FeFETs load. Directly applying these existing countermeasures to the P-SCA protection for FeFETs induces huge challenges, especially for the balance between power side-channel resistance and corresponding overheads.To address this issue, we leverage the unique features of FeFETs and propose ProtFe, namely the protection methods for FeFET-based memories, including the pipelined multi-step write strategy (PiMWrite) and the split array design (SpA). PiMWrite is proposed for general FeFET-based memories, and inserts specially designed intermediate states to mitigate information leakage with pipelined steps to reduce overheads. SpA is proposed for custom FeFET-based memories, and simultaneously writes two split portions of the array with shared minimized peripherals to go beyond the balance between security and overheads. Simulation results show that PiMWrite expands the search space of a single power trace to 21× and involves nearly zero hardware penalties. SpA presents 33× search space improvement with negligible latency, 0.6% area, and only 7.1% energy overhead. ProtFe achieves improved balance between security and overheads, compared with the state-of-the-art works.