Controllable growth of bilayer WS₂ by chemical vapor deposition and application for photodetectors

WS2 is a promising material in the next generation integrated circuit applications and its electrical and optoelectronic characteristics is dependent on the number of layers. Here, a simple and scalable synthesis of WS2 bilayers via chemical vapor deposition (CVD) is demonstrated by finely controlling the time of introducing sulfur. The optical and microstructural characterization of the as-grown bilayer WS(2 )show a uniform single crystal quality. The photodetector based on bilayers WS2 exhibits relatively good performance.