Monolayer WSe2 films synthesized by confined-space chemical vapor deposition

Abstract

Tungsten diselenide (WSe2) is an important p-type two-dimensional (2D) semiconductor. However, a route to synthesize its monolayer films that simultaneously exhibit spatial uniformity, high crystalline quality, and full coverage remains elusive. Here, we demonstrate the growth of centimeter-scale uniform WSe2 monolayer films via a confined-space chemical vapor deposition method. Monolayer WSe2 films can be efficiently synthesized with minimal precursor consumption within 5 min. Crystalline structure analysis and spectroscopy measurements, together with the statistically analyzed transfer curves of an array of 25 transistors, confirm the good uniformity of the WSe2 film. This approach provides a scalable route to produce large-scale, homogeneous WSe2 films, which are crucial for electronic and integrated-circuit applications based on 2D semiconductors.