Wafer-Scale Transfer of MXene Films with Enhanced Device Performance via 2D Liquid Intercalation

Wafer-scale transfer processes of 2D materials significantly expand their application space in scalable microelectronic devices with excellent and tunable properties through van der Waals (vdW) stacking. Unlike many 2D materials, wafer-scale transfer of MXene films for vdW contact engineering has not yet been reported. With their rich surface chemistry and tunable properties, the transfer of MXenes can enable enormous possibilities in electronic devices using interface engineering. Taking advantage of the MXene hydrophilic surface, a straightforward, green, and fast process for the transfer of MXene films at the wafer scale (4-inch) is developed. Uniform vdW stacking of several types of large-area heterojunctions including MXene/MXene (Ti3C2Tx, Nb2CTx, and V2CTx), MXene/MoS2, and MXene/Au is further demonstrated. Multilayer support is applied to minimize damage or deformation in the transfer process of patterned Ti3C2Tx film. It allows us to fabricate thin film transistors and manipulate the MXene/MoS2 interface through the intercalation of various 2D liquids. Particularly noteworthy is the significant enhancement of the interfacial carrier transfer efficiency by approximate to 2 orders of magnitude using hydrogen iodide (HI) intercalation. This finding indicates a wide range of possibilities for interface engineering by transferring MXene films and employing liquid-assisted interfacial intercalation. An efficient and straightforward transfer process is developed for 4-inch wafer-scale Ti3C2Tx MXene films, in which damage and deformation are minimized. Uniform vdW stacking of several types of large-area heterojunctions MXene/MoS2/MXene are well demonstrated. By utilizing 2D liquid reductants to modify the MXene/MoS2 interface, a more than 100-fold increase in carrier transfer efficiency is achieved. image