Recent Experimental Breakthroughs on 2D Transistors: Approaching the Theoretical Limit

Since Si-based Moore's law is physically limited, 2D semiconductors are proposed as successors to continue shrinking the transistor size for more Moore electronics. However, limited by experimental technology bottlenecks, the theoretical predicted superiorities of the 2D transistors over the state-of-the-art Si transistors have been lacking concrete evidence for a decade. In this review, recent exciting experimental breakthroughs for 2D transistors are presented, including gate length miniaturization to a sub-1 nm limit, electrode contact optimization to the resistance quantum limit, high-quality dielectric fabrication with an equivalent oxide thickness to sub-0.5 nm, novel architecture form (2D fin field-effect transistor), and back-end-of-line integration of directly grown 2D materials on Si complementary metal-oxide-semiconductor circuits. Remarkably, an ultrashort channel, Ohmic contact, ballistic transport, and ultrathin dielectric layer are simultaneously satisfied in the 2D InSe transistor, and device performances approaching the theoretical limit are observed. The measured key figures of merit of the ideal 2D InSe transistor are comparable to or even surpass those of the Si transistors. Finally, the challenges and outlook on more Moore electronics based on 2D transistors are highlighted. This article reviews recent breakthroughs in 2D transistor technology, including sub-nanometer gate length, ultra-low resistance contact, atomically thin dielectric, novel architecture form (2D fin field-effect transistor), and direct integration with Si complementary metal-oxide-semiconductor. The high-performance 2D InSe transistor approaches theoretical limit. The remaining challenges and exciting future prospects of 2D transistors for extending Moore's Law are also highlighted. image