Ultrahigh‐Sensitive Broadband Photodetectors Based on Dielectric Shielded MoTe2/Graphene/SnS2 p–g–n Junctions
Abstract
2D atomic sheets of transition metal dichalcogenides (TMDs) have a tremendous potential for next‐generation optoelectronics since they can be stacked layer‐by‐layer to form van der Waals (vdW) heterostructures. This allows not only bypassing difficulties in heteroepitaxy of lattice‐mismatched semiconductors of desired functionalities but also providing a scheme to design new optoelectronics that can surpass the fundamental limitations on their conventional semiconductor counterparts. Herein, a novel 2D h‐BN/p‐MoTe2/graphene/n‐SnS2/h‐BN p–g–n junction, fabricated by a layer‐by‐layer dry transfer, demonstrates high‐sensitivity, broadband photodetection at room temperature. The combination of the MoTe2 and SnS2 of complementary bandgaps, and the graphene interlayer provides a unique vdW heterostructure with a vertical built‐in electric field for high‐efficiency broadband light absorption, exciton dissociation, and carrier transfer. The graphene interlayer plays a critical role in enhancing sensitivity and broadening the spectral range. An optimized device containing 5−7‐layer graphene has been achieved and shows an extraordinary responsivity exceeding 2600 A W−1 with fast photoresponse and specific detectivity up to ≈1013 Jones in the ultraviolet–visible–near‐infrared spectrum. This result suggests that the vdW p–g–n junctions containing multiple photoactive TMDs can provide a viable approach toward future ultrahigh‐sensitivity and broadband photonic detectors.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Dec 14, 2018
- Source ID
- 10.1002/adma.201805656
Entities
People
- Alei Li
- Fangdong Tang
- Judy Z. Wu
- Liyuan Zhang
- Peipei Wang
- Peng Wang
- Qianxue Chen
- Rui Chen
- Tailei Qi
- Youpin Gong
- Yuan Gan
Organizations
- Army Research Office
- Harbin Institute of Technology
- National Natural Science Foundation of China
- National Science Foundation
- Southern University of Science and Technology
- University of Kansas