Strain‐Assisted Large‐Scale 1T‐MoS 2 Synthesis and its Optical Synaptic Flash Memory Application

Abstract 2D transition‐metal dichalcogenides (TMDCs) have attracted attention as promising materials for next‐generation devices owing to their versatile electronic and optical properties. The phase variety of TMDCs provides strategic opportunities for performance enhancement. Herein, a novel method is proposed to synthesize wafer‐scale 1T phase MoS₂ and, simultaneously, induce a phase transition via a plasma‐assisted metal‐sulfidation process and spontaneous internal strain. With thicker MoS 2 layers, the strong internal strain during synthesis suppresses the undesirable phase transition from the metastable 1T phase to the 2H phase, ensuring stabilization of the 1T phase. Furthermore, as‐synthesized 1T‐MoS₂ shows remarkable electrical properties owing to the narrow bandgap (0.4 eV) of its semi‐metallic state. As a result, the 1T‐phase MoS₂ floating gate (1T‐FG) flash memory demonstrates…