Optimal light harvesting in 2D semiconductor heterostructures

Abstract

Optoelectronics with two dimensional (2D) heterostructures combining transition metal dichalcogenides (TMDCs) and other semiconductors in hybrid stacks is potentially promising because of the possibility of fabricating devices with high efficiency and new properties. Ultrafast charge transfer across the interface and long lifetime of carriers makes the vertical geometry attractive with respect to traditional bulk heterostructures. In such ultrathin structures, the multiple boundaries and the thickness of each material play a key role in the interaction of light with the device and can strongly influence the device performance. In this article we study light harvesting in 2D InSe/MoS 2 semiconductor heterostructures by measuring Raman enhancement or attenuation as a function of layer thicknesses. Measurements are precisely reproduced by the calculation of the light emission, and the field distribution inside the heterostructure. Optimizing layer thickness and material interfaces has a significant effect on the light distribution in such 2D heterostructures with layer thickness in the region of a few tens of nanometers, providing a means to enhance the performance of emerging 2D semiconductor-heterostructure optoelectronics.

A high performance self-driven photodetector based on a graphene/InSe/MoS2 vertical heterostructure

“…Few devices have been reported where the junction is between materials with the same kind of majority charge carriers like for example WS 2 /MoS 2 with n-n type and Se/polyaniline with p-p type heterostructures 14,15 , in which similar rectifying properties and bipolar behavior can also exist. In our previous study, we combined n-type InSe with n-type MoS 2 and studied light interaction within vertical VDW confirmed by our previous study 16 . Graphene was prepared on glass using the anodic bonding method 19 and wedging transferred onto the InSe/MoS 2 followed by plasma etching to complete the graphene/InSe/MoS 2 heterostructure.…”

Recent Advances on Tuning the Interlayer Coupling and Properties in van der Waals Heterostructures

“…Inkjet printing could directly print large-scale vdW heterostructures onto substrate with low cost, while the preparation of highquality inks is required. Through these methods, various types of 2D vdW heterostructures have been successfully synthesized, such as graphene/TMDCs, [41,42] TMDCs/TMDCs, [43][44][45] black phosphorus (BP)/TMDCs, [46] h-BN/graphene, [47] etc. As an easy-to-understand and high-flexible approach, mechanical stacking method is applicable to most 2D materials, and the performance of these heterostructures could be manipulated by accurately adjusting the twist angle of the two layers.…”

Production Methods of Van der Waals Heterostructures Based on Transition Metal Dichalcogenides

“…A novel mechanical exfoliation method, so-called "random transfer", was proposed by Chen's group to fabricate vertical heterostructures [65]. The few-layer BP and WSe2 were both mechanically exfoliated from bulk counterparts (Figure 4a-c).…”

“…The cross-sectional TEM image confirmed the heterostructures and a thin barrier (~1.8 nm) at the interface between SnSe2 and WSe2 is formed. A novel mechanical exfoliation method, so-called "random transfer", was proposed by Chen's group to fabricate vertical heterostructures [65]. The few-layer BP and WSe 2 were both mechanically exfoliated from bulk counterparts (Figure 4a-c).…”