Two-Dimensional MoS₂ Logic Inverter

Abstract

Inverters are crucial in digital electronics as building blocks of logic circuits. The overall functionality of integrated circuits strongly depends on the performance of their components, whose continuous improvement is a key area of research. However, conventional inverter circuits, typically based on bulk semiconductors, face several limitations, including limited scalability, increasing power consumption, and significant transit time. Two-dimensional (2D) materials with unique electrical properties offer a potential solution to overcome these constraints. In this work, we fabricate and investigate the electrical properties of a resistive load inverter entirely based on molybdenum disulfide (MoS2). A thinner MoS2 flake is used as the channel of the inverter's driver transistor, exhibiting an n-type behaviour with a high ION/IOFF ratio of 107 and mobilities up to 19cm2V−1s−1 for Vds=1V. The resistive load of the circuit consists of a thicker flake, which demonstrates lower gate tunability and higher conductivity. Specifically, it shows an ION/IOFF ratio smaller than 103 and mobility as high as 34cm2V−1s−1 for Vds=1V. The inverter presents a maximum output voltage Vmax=1V and a minimum output voltage Vmin=0.65V. It is also characterized by large noise margins, NML=0.94V and NMH=0.65V. Moreover, a possible strategy to enhance the inverter efficiency is discussed by analyzing different load resistances. This work highlights MoS2-based inverters as a promising step toward low-power and scalable nanoelectronics.