Confined Growth of 2D Materials and their Heterostructures

Two-dimensional (2D) materials and their heterostructures show a promising path for next generation electronics. Nevertheless, there are challenges with (i) controlling monolayer (ML)-by-ML 2D material growth, (ii) maintaining single-domain growth, and (iii) controlling the number of layers and crystallinity at the wafer-scale. The deterministic confined growth techniques disclosed here address these challenges simultaneously to produce wafer-scale single-domain 2D MLs and their heterostructures on arbitrary substrates. The growth of the first nuclei is confined by patterning SiO2 masks on 2-inch substrates to define selective or confined growth areas. Each growth area or trench is just a few microns wide and is filled with a single-domain ML before the second set of nuclei is introduced. Growing the second set of nuclei within the trenches yields an array of single-domain bilayers exhibit excellent performance over the entire wafer.