High-Performance Monolayer BeN2 Transistors With Ultrahigh On-State Current: A DFT Coupled With NEGF Study

Conventional field-effect transistors (FETs) based on silicon downscaling are approaching physical limits, and thus, it is urgent to explore additional novel solutions to address this issue. The 2-D semiconductors have unique advantages as the channel material and provide a promising prospect for high-performance FETs in the post-Moore era. In this work, a new 2-D semiconductor, monolayer BeN
₂
, is studied for the FET performance limits through first-principle quantum-transport simulations. Monolayer BeN
₂
exhibits a graphene-like planar structure with a direct bandgap of 1.3 eV. Transfer characteristics of sub-10-nm BeN
₂
FETs are thoroughly assessed through scaling gate length. In particular, 2-D BeN
₂
FETs with 10-nm gate present the ultrahigh ON-state current above
$4500\,\, \mu \text{A}/\mu \text{m}$
for high-performance applications. Also, we realize the significant reduction of gate length (only 2.5 nm) against the International Technology Roadmap for Semiconductors (ITRS) requirements through introducing underlap structures. In addition, the performance of single devices based on monolayer BeN
₂
is evaluated and compared with some of the recently proposed 2-D devices.