High-Yield Ti₃ C₂ T_x MXene-MoS₂ Integrated Circuits.

Abstract

It is very challenging to employ solution-processed conducting films in large-area ultrathin nanoelectronics. Here, spray-coated Ti₃ C₂ T_x MXene films as metal contacts are successfully integrated into sub-10 nm gate oxide 2D MoS₂ transistor circuits. Ti₃ C₂ T_x films are spray coated on glass substrates followed by vacuum annealing. Compared to the as-prepared sample, vacuum annealed films exhibit a higher conductivity (≈11 000 S cm^-1 ) and a lower work function (≈4.5 eV). Besides, the annealed Ti₃ C₂ T_x film can be patterned through a standard cleanroom process without peeling off. The annealed Ti₃ C₂ T_x film shows a better band alignment for n-type transport in MoS₂ channel with small work function mismatch of 0.06 eV. The MoS₂ film can be uniformly transferred on the patterned Ti₃ C₂ T_x surface and then readily processed through the cleanroom process. A large-area array of Ti₃ C₂ T_x MXene-MoS₂ transistors is fabricated using different dielectric thicknesses and semiconducting channel sizes. High yield and stable performance for these transistor arrays even with an 8 nm-thick dielectric layer are demonstrated. Besides, several circuits are demonstrated, including rectifiers, negative-channel metal-oxide-semiconductor (NMOS) inverters, and voltage-shift NMOS inverters. Overall, this work indicates the tremendous potential for solution-processed Ti₃ C₂ T_x MXene films in large-area 2D nanoelectronics.