Direct Synthesis of a Self-Assembled WSe2/MoS2 Heterostructure Array and its Optoelectrical Properties

Abstract

n heterojunction shows not only high rectification (ideality factor: 1.18) but also promising optoelectrical properties with a high responsivity of 5.39 A W&#8722

1 and response speed of 16 &micro

s. As a feasible application, a WSe2/MoS2&#8208

based photodiode array (10 × 10) is demonstrated, which proves that the photosensing system can detect the position and intensity of an external light source. The solution&#8208

based growth of hierarchical structures with various alignments could offer a method for the further development of large&#8208

area electronic and optoelectronic applications.

Functional van der Waals heterojunctions of transition metal dichalcogenides are emerging as a potential candidate for the basis of next&#8208

generation logic devices and optoelectronics. However, the complexity of synthesis processes so far has delayed the successful integration of the heterostructure device array within a large scale, which is necessary for practical applications. Here, a direct synthesis method is introduced to fabricate an array of self&#8208

assembled WSe2/MoS2 heterostructures through facile solution&#8208

based directional precipitation. By manipulating the internal convection flow (i.e., Marangoni flow) of the solution, the WSe2 wires are selectively stacked over the MoS2 wires at a specific angle, which enables the formation of parallel&#8208

and cross&#8208

aligned heterostructures. The realized WSe2/MoS2&#8208

based p&#8211