Work

Inherently Selective and Anisotropic Ruthenium Deposition on the Basal Plane of Single‐Layer Transition Metal Dichalcogenide Crystals

Year: 2025

Type: article

Abstract: Area‐selective deposition (ASD) provides promise to facilitate the fabrication of nano‐electronic devices with 2D transition metal dichalcogenide channels. This paper explores Ru ASD by chemical vapor deposition (CVD) on a Si/SiO 2 substrate that is partly covered by triangular single‐layer WS 2 crystals. Opposite to most chemically driven deposition techniques, this Ru deposition is inherently selective, with the WS 2 basal plane being more active than the WS 2 crystals edges. Continuous Ru layers form on the basal plane of the WS 2 crystals with less than 2% selectivity loss on the SiO 2 surface. Ru deposition initiates near the WS 2 crystal edges and expands over the WS 2 basal plane with a lateral growth rate that is more than 10 times larger than the vertical growth rate. The anisotropic growth is attributed to diffusion‐mediated aggregation of Ru adspecies on the WS 2 basal plane. Moreover, experimental observations are consistent with theoretical predictions for self‐confined deposition on the WS 2 crystals, while there is no physical barrier to prevent lateral overgrowth. The obtained insights are relevant for a wide range of applications that rely on chemically driven deposition on 2D materials, and promote further research on precise nanopattern replication by self‐confined growth without relying on physical barriers.

Source: Advanced Functional Materials

DOI: 10.1002/adfm.202516482