Characterization of Double HfZrO2 based FeFET toward Low-Voltage Multi-Level Operation for High Density Nonvolatile Memory

A double HfZrO
2
(HZO) ferroelectric field-effect transistor (FeFET) is demonstrated with ultra-low operating voltage as |V
P/E
| = 3 V to achieve multilevel cell (MLC) nonvolatile memory (NVM). Compared to a single FE-HZO FeFET, the metal/ferroelectric/metal/ferroelectric/Si (MFMFS) structure results not only in a reduction of V
P/E
, but also provides a feasible memory window (MW) of 1.9 V for MLC operation. In addition, the metal/ferroelectric/insulator/ ferroelectric/Si (MFIFS) FeFET exhibits a MW as high as >2.5 V. The double HZO FeFET has potential to improve power consumption and enhance memory density for MLC-NVM applications.