High-Yield Ti 3 C 2 T x MXene-MoS 2 Integrated Circuits

Abstract

It is very challenging to employ solution-processed conducting films in large-area ultrathin nanoelectronics. In this manuscript, spray-coated Ti3C2Tx MXene films as metal contacts are successfully integrated into sub-10 nm gate oxide two-dimensional (2D) MoS2 transistor circuits. The Ti3C2Tx films are prepared on glass substrates by a spray coating process followed by vacuum annealing. Compared to the as-prepared sample, the films after a vacuum annealing exhibit a higher conductivity (∼ 11,000 S/cm) and a lower work function (∼ 4.5 eV). Besides, the annealed Ti3C2Tx film can be patterned through a standard cleanroom process without peeling-off. The annealed Ti3C2Tx 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 Ti3C2Tx surface and then readily processed through the cleanroom process. A large-area array of Ti3C2Tx MXene-MoS2 transistors is fabricated using different dielectric thicknesses and semiconducting channel sizes. We demonstrate high yield and stable performance for these transistor arrays even with an 8 nm thick dielectric layer. Besides, several circuits are demonstrated, including rectifiers, NMOS inverters, and voltage-shift NMOS inverters. Overall, this work indicates the tremendous potential for solution-processed Ti3C2Tx MXene films in large-area 2D nanoelectronics.