Intrinsic Ohmic Contacts and Polarity‐Tunable Schottky Barriers in M₈X₁₂–Graphene (M = Mo, W; X = S, Se) van der Waals Heterostructures for High‐Performance and Bipolar Device Applications

Abstract

Considering the synthesis of novel 2D monolayers such as W8Se12, which are ideal for nanoelectronics, in this study, density‐functional theory is utilized to examine M8X12/G (M = Mo, W; X = S, Se) van der Waals heterostructures (vdWHs). Herein, the crucial role of intrinsic Ohmic contacts and Schottky barrier heights (SBH) at metal/semiconductor interfaces in these heterojunctions, which are vital for efficient current flow and minimal resistance, and their impact on high‐performance electronic and bipolar device applications are focused on. In these findings, it is revealed that W8Se12/G forms an Ohmic contact with a 75.4% tunneling probability, while Mo8S12/G, W8S12/G, and Mo8Se12/G develop n‐type Schottky contacts with remarkably low SBHs of 0.110, 0.136, and 0.064 eV, respectively. The adaptability of these Schottky barriers is demonstrated by modifying the interlayer distance or applying an electric field, leading to transitions from n‐type to p‐type contacts. Additionally, mechanical strain influences the contact type, offering valuable insights for future nanoelectronic and bipolar device technologies. This comprehensive analysis underlines the versatile electronic behavior of M8X12/G vdWHs, highlighting their potential in advancing nanoelectronic devices.