Thickness Dependence of Optoelectronic Properties of Molybdenum Diselenide-Based Nanodevices

Two-dimensional molybdenum diselenide (MoSe2) has application potential in optical and optoelectronic devices. In this study, we fabricated field-effect transistors based on two-dimensional MoSe2 flakes and investigated the effect of flake thickness on the optoelectronic properties of the devices. An increase in MoSe2 flake thickness caused an enhancement in the optoelectronic performance of the device under 532 nm laser illumination. The thickest MoSe2 flake-based device showed the highest photoresponsivity of approximately 753 A W−1, and the external quantum efficiency and specific detectivity of the device were 175.891%, and 2.8 × 1011 cm Hz1/2 W−1, respectively. The prepared two-dimensional MoSe2 flakes exhibited promising properties for nano-optoelectronic device applications.