A monolayer MoS2 p-n homogenous photodiode with enhanced photoresponse by piezo-phototronic effect. (13th June 2018)

• Record Type: Journal Article
• Authors: Zhang, Ke; Zhai, Junyi; Wang, Zhong Lin
• Is Part Of: 2D materials. Volume 5:Number 3(2018)
• Publication Date: 2018-06-13
• Subjects: TMDCs -- piezoelectricity -- p-n homojunction -- piezo-phototronic effect -- enhanced photoresponse; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/aac96b
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Transition-metal dichalcogenides (TMDCs) have recently open a new perspective in electronics and optoelectronics due to their unique planar crystal structures and incredible physical characteristics. Strong in-plane piezoelectricity is their unique property owing to non-centrosymmetric structure, differing from other two dimension (2D) materials, such as graphene and black phosphorus. In this work, we develop a flexible photodiode based on monolayer MoS2 lateral p-n homojunction with significant enhancement in photoresponsivity and detectivity. Piezo-phototronic effect is used to achieve this enhancement by adjusting the barrier height and broadening depletion zone at p-n junction interface under external strain. The wider depletion zone benefits the separation and transport of photogenerated carriers, thus enhancing the photocurrent. When a 0.51% external static tensile strain was applied, the photoresponsivity and detectivity are improved up to 1162 A W −1 and 1.72 × 10 12 Jones, with about 619% and 319% enhancement compared with strain-free state, respectively. Consequently, this work provides an effective strategy to utilize unavoidable external strain to improve TMDCs-based optoelectronic devices performance. At the same time, it has reference meaning to achieve flexible, low-consumption and high-performance 2D devices without electric gate-control.