This new paper reports the first synthesis of micron-sized WS2 crystals by ALD using bis(t-butylimido)bis(trimethylsilylmethyl)tungsten and H2S, followed by sulfur annealing. The films are nanocrystalline with mixed phases and impurities before annealing but show Raman peaks of WS2 and larger crystals after annealing. The substrate affects the shape of the crystals: silicon leads to flake pyramids or flowers, ZnS leads to crumpled flowers, and Al2O3 leads to thin flakes.
Synthesis of Micron-Sized WS2 Crystallites Using Atomic Layer Deposition and Sulfur Annealing