Molecular ferroelectric/semiconductor interfacial memristors for artificial synapses

With the burgeoning developments in artificial intelligence, hardware implementation of artificial neural network is also gaining pace. In this pursuit, ferroelectric devices (i.e., tunneling junctions and transistors) with voltage thresholds were recently proposed as suitable candidates. However, their development is hindered by the inherent integration issues of inorganic ferroelectrics, as well as poor properties of conventional organic ferroelectrics. In contrast to the conventional ferroelectric synapses, here we demonstrated a two-terminal ferroelectric synaptic device using a molecular ferroelectric (MF)/semiconductor interface. The interfacial resistance can be tuned via the polarization-controlled blocking effect of the semiconductor, owing to the high ferroelectricity and field amplification effect of the MF. Typical synaptic features including spike timing-dependent plasticity are substantiated. The introduction of the semiconductor also enables the attributes of optoelectronic synapse and in-sensor computing with high image recognition accuracies. Such interfaces may pave the way for the hardware implementation of multifunctional neuromorphic devices.