Three-Dimensional Integration of Multi-Channel MoS₂ Devices for High Drive Current FETs

As the dimensions of transistors have scaled down over the last decades, technology has evolved from planar silicon (Si) to silicon-on-insulator (SOI) to FinFETs to counter in particular short channel effects. To further improve the electrostatics of field-effect transistors (FETs), researchers recently are exploring the use of stacked gate-all-around Si nano-sheet device structures [1]. These novel devices, like FinFETs, give rise to a larger effective channel width for the same footprint and thus allow for higher current drives. The ultimate extension of such a structure would utilize an atomically thin sheet of semiconductor, which makes two-dimensional (2D) transition metal dichalcogenides (TMDs) an ideal choice for applications that rely on the vertical stacking of multiple 2D sheets. In this work we demonstrate for the first time the three-dimensional (3D) integration of two vertically stacked MoS 2 FETs which shows promising performance specs towards high current drives.