Unveiling charge-trapping storage capacity in MoS2/BiFeO3 heterostructure

Abstract

Charge-trapping memory emerges as one of the prime candidates for nonvolatile memory architectures, yet the empirical selection of charge storage media demands further investigation. Leveraging the inherent oxygen vacancy-mediated trapping mechanism, ferroelectric BiFeO3 (BFO) enables a tunable charge confinement. Herein, through an improved sol-gel method, the preparation protocol of BFO was rigorously engineered, enabling realization of centimeter-scale crystalline films on SiO2/Si substrates. Integrating BFO with two-dimensional van der Waals semiconductor MoS2, we constructed a heterostructure-based charge-trapping memory featuring enhanced retention and scalable integration. The device exhibits a maximum memory window of ∼90 V, an ON/OFF current ratio of ∼105, and a write–erase current ratio of ∼103. With a saturation storage capacity of up to 1013 cm−2 and the well-defined charge retention mechanism, the MoS2/BFO heterostructure also mimics biological synaptic behaviors, offering alternative prospects for BFO-based memories and neuromorphic computing.