High-Throughput Computational Design of Inorganic Molecular Crystal-Based High-κ Dielectrics for Two-Dimensional Electronics.

Abstract

Inorganic molecular crystals (IMCs) hold great promise as high-κ dielectrics for two-dimensional (2D) electronics due to their dangling-bond-free surfaces and the capability of direct integration on 2D semiconductors. However, only a limited number of IMCs have been identified so far, and interface properties between IMC-based high-κ dielectrics and 2D semiconductors remain largely unexplored. Here, we present an efficient high-throughput screening of IMC-based high-κ dielectrics from a large materials database, of which 6 IMCs (Sb₂S₂O₉, two Bi₂O₃ phases, As₂S₂O₉, Sb₂O₃, and Te₂H₂O₃F₄) have been predicted to be the most promising gate dielectrics for 2D semiconductors due to their optimal trade-off between dielectric constant and band gap, as well as facile growth possibility. For predominant 2D semiconducting channel materials such as molybdenum disulfide (MoS₂) and black phosphorene (BP), the respective promising IMC-based high-κ dielectrics have been pinpointed. We further showcase two high-performance 2D semiconductor/IMC interfaces (BP/Sb₂S₂O₉ and MoS₂/Bi₂O₃), as evidenced by large band offsets, high defect tolerance, and low leakage current. The downscaling capability of the IMCs to the sub-1 nm equivalent oxide thickness (EOT) regime is also unraveled for both dynamic random access memory (DRAM) and central processing unit (CPU) applications. Our results accelerate the exploration of IMC-based high-κ dielectrics and promote the development of high-performance 2D electronics.