Patterning of Wafer‐Scale MXene Films for High‐Performance Image Sensor Arrays

Abstract

As a rapidly growing family of 2D transition metal carbides and nitrides, MXenes are recognized as promising materials for the development of future electronics and optoelectronics. So far, the reported patterning methods for MXene films lack efficiency, resolution, and compatibility, resulting in limited device integration and performance. Here, a high‐performance MXene image sensor array fabricated by a wafer‐scale combination patterning method of an MXene film is reported. This method combines MXene centrifugation, spin‐coating, photolithography, and dry‐etching and is highly compatible with mainstream semiconductor processing, with a resolution up to 2 µm, which is at least 100 times higher than other large‐area patterning methods reported previously. As a result, a high‐density integrated array of 1024‐pixel Ti3C2Tx/Si photodetectors with a detectivity of 7.73 × 1014 Jones and a light–dark current ratio (Ilight/Idark) of 6.22 × 106, which is the ultrahigh value among all reported MXene‐based photodetectors, is fabricated. This patterning technique paves a way for large‐scale high‐performance MXetronics compatible with mainstream semiconductor processes.

Applications of MXenes in human-like sensors and actuators

“…The transistor array based on MXene can be prepared with patterning techniques, such as direct writing and inject printing. They have drawbacks of low pixel resolution [137][138][139].…”

A room temperature ammonia gas sensor based on cerium oxide/MXene and self-powered by a freestanding-mode triboelectric nanogenerator and its multifunctional monitoring application

“…17 Overall, the unique layered morphology, high electrical conductivity, high surface area, excellent hydrophilicity, good thermal stability, and environmentally friendly characteristics of MXenes make them an ideal material for developing different sensor devices. 18 Among them, Ti 3 C 2 T x is one of the most widely studied MXenes. 19 Few other types of MXenes have been studied.…”

Uniform self-rectifying resistive random-access memory based on an MXene-TiO2 Schottky junction

“…32,33 It is worth noting that during the preparation of MXenes, when a certain A atomic layer is removed from the MAX phase precursor by hydrofluoric acid etching, some adjacent atoms will inevitably fall off, leading to the disordered anion–cation vacancies or vacancy clusters, which greatly increase the trap density of MXenes inherently. 34–36 Recently, as the wafer-scale MXene film patterning with high resolution has been realized, 37 it opens up new avenues for designing highly-active and long-life electrode candidates for fabricating uniform RRAMs based on the interface-trap modulation model.…”