Site-Specific Positioning and Patterning of MoS₂ Monolayers: The Role of Au Seeding

Monolayers of transition metal dichalcogenides (TMDs) are attractive for various modern semiconductor devices. However, the limited control over the location, yield, and size distribution of the products using current synthesis methods has severely limited their large-scale applicability. Herein, we identify the ability to use metal (e.g., Au) nanoparticles to seed the growth of MoS₂ monolayers and thereby provide a means to achieve programmable and controllable synthesis. In this study, prepatterned Au seeds are used as heterogeneous nucleation sites to induce the formation of desired geometries of MoS₂ monolayers via chemical vapor deposition. Our experimental and theoretical results shed light on the growth mechanism driving the formation of MoS₂ monolayers at these sites, revealing that the seeding effect originates from the favorable formation energy of MoS₂ on the Au surface. A field-effect transistor with a predesigned channel geometry exhibits electronic performance that compares nicely with previously reported MoS₂ monolayer devices. We believe this study contributes fundamental insights into controlled synthesis of TMD monolayers, making integration of these materials into emerging electronic devices more attainable.