An Embedded Three-Bit-Per-Cell Two-Transistors and One-Ferroelectric-Capacitance Nonvolatile Memory

We present a nonvolatile memory of two transistors and one ferroelectric-capacitance with the three-bit-per-cell capability. With a control transistor, the memory can be turned-off correctly when the ferroelectric capacitance is programmed such that the threshold-voltage of the unit cell shifts to a deep negative value. This unit cell can be programmed in 80 ns and erased in 20 ns. The conductance can be tuned gradually in
$2.5\times 10^{{4}}$
folds of the on-off ratio with 30 cycles by pulse operations. The eight conductance values can be cycled more than
$10^{{7}}$
times. Data stored in distinguished eight conductance values can be retained in 80 Celsius degrees for ten years. This work offers an applicable solution for embedded non-volatile memories with ferroelectric mechanisms.