Synaptic Behaviors in Ferroelectric-Like Field-Effect Transistors with Ultrathin Amorphous HfO(2) Film

We demonstrate a non-volatile field-effect transistor (NVFET) with a 3-nm amorphous HfO(2) dielectric that can simulate the synaptic functions under the difference and repetition of gate voltage (V(G)) pulses. Under 100 ns write/erase (W/E) pulse, a memory window greater than 0.56 V and cycling endurance above 10(6) are obtained. The storied information as short-term plasticity (STP) in the device has a spiking post-synaptic drain current (I(D)) that is a response to the V(G) input pulse and spontaneous decay of I(D). A refractory period after the stimuli is observed, during which the I(D) hardly varies with the V(G) well-emulating the bio-synapse behavior. Short-term memory to long-term memory transition, paired-pulse facilitation, and post-tetanic potentiation are realized by adjusting the V(G) pulse waveform and number. The experimental results indicate that the amorphous HfO(2) NVFET is a potential candidate for artificial bio-synapse applications.