Pulsed laser deposition assisted grown continuous monolayer MoSe2

Abstract

As compared with sulfur, the low reactivity of selenium makes it more challenging to synthesize high quality continuous single layer selenides required for practical applications. Here, we present the synthesis of monolayer MoSe₂ by selenization of a pulsed laser deposited MoO₃ film on SiO₂/Si and sapphire substrates. The laser energy was carefully varied to optimize the growth of highly uniform, continuous monolayer films. Morphological characterization including optical microscopy, field emission scanning electron microscopy and atomic force microscopy results clearly demonstrate that the synthesized film is monolayer, continuous and homogeneous. The Raman and photoluminescence maps of the continuous film exhibit uniform brightness, indicating the uniform and homogeneous nature of the film. Moreover, the full width at half maximum values of A_1g and A exciton peaks were found to be 3.7 cm⁻¹ and 24 nm, respectively, showing the excellent optical quality of the grown film.