Split-Gate FeFET (SG-FeFET) with Dynamic Memory Window Modulation for Non-Volatile Memory and Neuromorphic Applications

In this work, we propose a novel split-gate FeFET (SG-FeFET) with two separate external gates to dynamically modulate the memory window (MW) for non-volatile memory and neuromorphic applications. During read operation, only one gate is turned on to decrease the area ratio (AFE/AIL) of ferroelectric layer to insulator layer, which increases MW and read current ratio (IRead-1/IRead-0). During write operation (program/erase), both two gates are turned on to increase AFE/AIL, which decreases MW, thereby resulting in lower write voltage (VWrite). Compared to FeFET, SG-FeFET (1) Demonstrates lower VWrite ( =1.85V) and 59.5% reduction in write energy at fixed IRead-1/IRead-0; (2) Exhibits lower read energy (-11.3%) and higher IRead-1/IRead-0 (=8.6E6) at fixed VWrite; (3) Allows random access and eliminates half-select disturb; (4) Preserves higher endurance due to lower VWrite and charge trapping. SG-FeFET as synaptic device also exhibits superior symmetry and linearity for potentiation and depression process. ? 2019 The Japan Society of Applied Physics.