Attoampere Level Leakage Current in Chemical Vapor Deposition-Grown Monolayer MoS2 Dynamic Random-Access Memory in Trap-Assisted Tunneling Limit

Abstract

MoS2, one of the most researched two-dimensional semiconductor materials, has great potential as the channel material in dynamic random-access memory (DRAM) due to the low leakage current inherited from the atomically thin thickness, high band gap, and heavy effective mass. In this work, we fabricate one-transistor-one-capacitor (1T1C) DRAM using chemical vapor deposition (CVD)-grown monolayer (ML) MoS2 in large area and confirm the ultralow leakage current of approximately 10(-18) A/mu m, significantly lower than the previous report (10(-15) A/mu m) in two-transistor-zero-capacitor (2T0C) DRAM based on a few-layer MoS2 flake. Through rigorous analysis of leakage current considering thermionic emission, tunneling at the source/drain, Shockley-Read-Hall recombination, and trap-assisted tunneling (TAT) current, the TAT current is identified as the primary source of leakage current. These findings highlight the potential of CVD-grown ML MoS2 to extend the retention time in DRAM and provide a deep understanding of the leakage current sources in MoS2 1T1C DRAM for further optimization to minimize the leakage current.