Achieving Ohmic and High‐Tunneling‐Probability Contacts in 2D Semiconductors via Hydrogen‐Bond‐Mediated Interfacial Coupling

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ABSTRACT Developing high‐performance electronics with two‐dimensional (2D) semiconductors is often hindered by high contact resistance at metal/semiconductor interfaces, which arises from the Schottky barrier for carrier injection and tunneling barrier for carrier transport. Conventional contact engineering faces a fundamental compromise: strong interfacial coupling induces Fermi‐level pinning (FLP), while weak van der Waals interactions mitigate FLP but introduces a large tunneling barrier. Here, we overcome this compromise by employing MXene electrodes on Janus MGeSiN 4 (M = Mo, W) semiconductors and modulating the interfacial interaction strength. Through selective surface termination of MXenes, Schottky, n‐type Ohmic, or p‐type Ohmic contacts can be achieved. Notably, medium‐strength interfacial coupling driven by hydrogen bonding in OH‐terminated MXene (OH‐MXene)/MGeSiN 4 contacts enables simultaneous Ohmic behavior and high tunneling probability. Specifically, the tunneling probability of OH‐MXene contacts ranges from 37.91% to 61.92%, with the maximum for Ti 3 C 2 (OH) 2 /WGeSiN 4 on the Si‐N side, significantly higher than F/O‐terminated MXene contacts (1.87% – 6.19%). Quantum transport simulations confirm superior current transport and charge injection efficiency in OH‐MXene/MGeSiN 4 devices. Furthermore, the Sure Independence Screening and Sparsifying Operator method identifies key descriptors governing both Schottky and tunneling barriers. Our results provide an efficient strategy for designing high‐performance contacts in 2D electronic devices.