Optoelectrical Molybdenum Disulfide (MoS₂)—Ferroelectric Memories

TLDR

The study aims to investigate the electronic and memory behavior of monolayer or few‑layer MoS₂ field‑effect transistors on a PZT gate dielectric, focusing on how polarization and interfacial phenomena influence device performance. The authors fabricated and tested MoS₂‑based FETs on PZT substrates, measuring electronic transport and memory characteristics to assess the impact of polarization and interfacial effects. MoS₂–PZT FETs exhibit pronounced hysteresis with high ON/OFF ratios, enabling nondestructive, low‑voltage, wide‑window memory operation that can be written and erased both electrically and optically, offering advantages over graphene and commercial FeRAMs and allowing instant optical erase of large data arrays.

Abstract

In this study, we fabricated and tested electronic and memory properties of field-effect transistors (FETs) based on monolayer or few-layer molybdenum disulfide (MoS2) on a lead zirconium titanate (Pb(Zr,Ti)O3, PZT) substrate that was used as a gate dielectric. MoS2–PZT FETs exhibit a large hysteresis of electronic transport with high ON/OFF ratios. We demonstrate that the interplay of polarization and interfacial phenomena strongly affects the electronic behavior and memory characteristics of MoS2–PZT FETs. We further demonstrate that MoS2–PZT memories have a number of advantages and unique features compared to their graphene-based counterparts as well as commercial ferroelectric random-access memories (FeRAMs), such as nondestructive data readout, low operation voltage, wide memory window and the possibility to write and erase them both electrically and optically. This dual optoelectrical operation of these memories can simplify the device architecture and offer additional practical functionalities, such as an instant optical erase of large data arrays that is unavailable for many conventional memories.