Quantum transport simulations of sub-5 nm bilayer Ga2O3 transistor for high-performance applications

Abstract Two-dimensional (2D) semiconductors with bizarre properties show great application potential for nanoscale devices, which is regarded as the Si alternation to extend the Moore’s Law in sub-5 nm era. In this study, we investigate the electronic structure and ballistic transport characteristics of sub-5 nm bilayer (BL) Ga 2 O 3 metal-oxide-semiconductor field-effect transistor (MOSFET) using the first-principles calculations and the nonequilibrium Green’s function method. Quasi-direct band structure with bandgap of 4.77 eV is observed in BL Ga 2 O 3 , and high electron mobility of 910 cm 2 V −1 s −1 at 300 K is observed under the full-phonon scattered processes. Due to the enlarged natural length, the gate-controllable ability of 2D Ga 2 O 3 n-MOSFET is suppressed with the increased layer. The transport characteristic investigation indicates that BL Ga 2 O 3 n-MOSFETs can meet the latest International Technology Roadmap for Semiconductors requirement for high-performance application until L g = 4 nm. The figures of merits including on-current, intrinsic delay time, and power delay product are showing competitive potential with the reported 2D materials. With the help of underlap structure, the device performance can be further improved in the sub-3 nm region. Our results indicate that BL Ga 2 O 3 is a promising candidate for sub-5 nm MOSFET applications.