Comprehensive Study of Electrode Effect in Metal/CuInP2S6/Metal Heterostructures

The layered van der Waals CuInP2S6 (CIPS) features interesting functional behaviors, including reversible ferroelectric polarization, Cu ion migration, negative capacitance effect, etc. Here, the CIPS flakes were exfoliated from CVT-grown high-quality single crystals, which fabricated into metal/CIPS/metal heterostructures by conventional photolithography. It was found that persisted in dominant out-of-plane polarization and minor in-plane polarization. Clear hysteresis current–voltage (I–V) loops, as well rectifying character, revealed heterostructures, indicating potential application a memory device. Additionally, different metal electrode could significantly modulate Schottky-like barrier at metal/CIPS interfaces, resulting symmetric or asymmetric I–V loops. complicated curves may have originated voltage-induced carrier (ion) trapping/detrapping. This work facilitate selection for CIPS-based device application.