A universal all-dry microfabrication method for sensitive electronic materials via an inorganic molecular lithographic mediator

Lithography is pivotal in fabricating micro/nanoscale patterns and processing materials for electronic microdevices. However, conventional organic polymeric resists inevitably entail the use of various chemical solutions or solvents, which especially compromise fragile electronic materials featuring atomic-level surfaces. Here, we introduce inorganic selenium molecules as a lithographic mediator for sensitive electronic material processing without direct exposure to solutions or solvents. Specifically, the inorganic selenium molecular film functions as both a lithographic mediator for direct patterning due to its weak intermolecular van der Waals interactions and as a protective encapsulation layer for atomic electronic materials without compromising structural and electronic characteristics. Wafer-scale arrays of sensitive materials with high-quality, sharp edges are facilely achieved by a non-destructive mechanical peeling of the selenium layer. This approach provides a solvent-free lithographic route for microfabricating sensitive materials and high-performance electronic devices. Conventional organic polymeric resists and chemical solutions used in microlithographic techniques can damage sensitive materials. Here, the authors report the application of inorganic selenium molecules as a lithographic mediator and encapsulation layer during the processing of various sensitive materials, such as perovskites and black phosphorus.