In Situ Fabrication of 2D WS₂/Si Type-II Heterojunction for Self-Powered Broadband Photodetector with Response up to Mid-Infrared

Abstract

The high-performance broadband photodetectors have attracted intensive scientific interests due to their potential applications in optoelectronic systems. Despite great achievements in two-dimensional (2D) materials based photodetectors such as graphene and black phosphorus, obvious disadvantages such as low optical absorbance and instability preclude their usage for the broadband photodetectors with the desired performance. An alternative approach is to find promising 2D materials and fabricate heterojunction structures for multifunctional hybrid photodetectors. In this work, 2D WS 2 /Si heterojunction with a type-II band alignment is formed in situ. This heterojunction device produced a high I on /I off ratio over 10, 6 responsivity of 224 mA/W, specific detectivity of 1.5 × 10 12 Jones, high polarization sensitivity, and broadband response up to 3043 nm. Furthermore, a 4 × 4 device array of WS 2 /Si heterojunction device is demonstrated with high stability and reproducibility. These results suggest that the WS 2 /Si type-II heterojunction is an ideal photodetector in broadband detection and integrated optoelectronic system.

Two-Dimensional Platinum Diselenide: Synthesis, Emerging Applications, and Future Challenges

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Interface‐Induced High Responsivity in Hybrid Graphene/GaAs Photodetector

“…Two‐dimensional (2D) graphene with its single‐atomic‐layer thickness offers superior electronic, optical, and mechanical properties 1–3. The integration of graphene with semiconductor materials has been proposed to enable construction of a 2D/three‐dimensional (3D) junction on the semiconductor surface that would enable carrier transport across the 2D/semiconductor interface with continued innovation in terms of the device physics 4–8. Recently, a type of hybrid graphene/semiconductor photodetector was developed successfully with ultrahigh responsivity and sensitivity by transferring either chemical vapor deposition (CVD)‐grown or exfoliated graphene layers onto the semiconductor substrates 9,10.…”

Asymmetric electrode incorporated 2D GeSe for self-biased and efficient photodetection

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