Contact Properties of Two-Dimensional Semiconductor As₂C₃ with Metals and Semimetals

The two-dimensional semiconductor As2C3, known for its ultrahigh carrier mobility of up to 4.45 × 105 cm2 V–1 s–1, holds significant potential for next-generation nanoelectronic devices. Selecting the appropriate electrodes is crucial for minimizing contact resistance and enhancing device performance. Using first-principles calculations, we systematically analyze the interface characteristics of As2C3 in conjunction with a range of metallic and semimetallic electrodes. Our findings indicate that both As2C3/Au and As2C3/Bi form efficient Ohmic contacts. At the same time, As2C3/graphene exhibits a Schottky contact, where the Schottky barrier height (SBH) can be tuned through external electric fields and vertical strain. Additionally, As2C3/NbS2 and As2C3/Sc demonstrate extremely low SBH, classifying them as quasi-Ohmic contacts. Notably, Sc-based contacts facilitate electron tunneling with probabilities reaching up to 100%. Upon contact with Au and Sc, a pronounced Fermi-level pinning (FLP) effect is observed in As2C3. These results offer valuable insights for the development and optimization of advanced As2C3-based electronic devices.