Emerging van der Waals Dielectrics of Inorganic Molecular Crystals for 2D Electronics

In the landscape of continuous downscaling metal-oxide-semiconductor field-effect transistors, two-dimensional (2D) semiconductors with atomic thinness emerge as promising channel materials for ultimate scaled devices. However, integrating compatible dielectrics with 2D semiconductors, particularly in a scalable way, remains a critical challenge that hinders the development of 2D devices. Recently, 2D inorganic molecular crystals (IMCs), which are free of dangling bonds and possess excellent dielectric properties and simplicity for scalable fabrication, have emerged as alternatives for gate dielectric integration in 2D devices. In this Perspective, we start with the introduction of structure and synthesis methods of IMCs and then discuss the explorations of using IMCs as the dielectrics, as well as some remaining relevant issues to be unraveled. Moreover, we look at the future opportunities of IMC dielectrics in 2D devices both for practical applications and fundamental research.