Resolution Limits and Their Effect on Structure and Morphology of Lithographically Defined TMD Synthesized by Lateral Conversion

Recently, we developed a wafer-scalable method to synthesize lithographically patterned transition metal dichalcogenides (TMDs), using a process that we call “lateral conversion.” Briefly, this method relies on the diffusion of chalcogen precursors to convert metal-oxide thin-films via interlayer diffusion, which proceeds from the exposed film edges at lithographically defined locations. In this work, we explore the resolution limits of our method and its effect on its structure and properties. The synthesis approach initially relied on photolithography to fabricate structures with micron-scale resolution. In this work, we show that this method is suitable to achieve lithographically defined sub-20nm features achievable using a block copolymer lithography. We were able to develop simple transfer techniques to lift the patterned structure and transfer it to a substrate of choice such as a silicon wafer or electron transparent substrate for TEM analysis. This allowed us to study the effect of synthetic parameters on the morphology and structure of the TMD and improve the quality of the TMD films.