Broadband few-layer MoTe₂photodetectors for array

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• High-performance broadband photodetector arrays are essential for sensing, imaging, and optical communications.
• Existing materials often struggle to achieve broadband coverage, fast response, and uniform performance simultaneously.
• Scalable fabrication methods for such advanced photodetectors are highly sought after.

Purpose of the Study:

• To present a novel photodetector array based on few-layer molybdenum ditelluride (MoTe2).
• To demonstrate the material's capability for stable broadband photoresponse from ultraviolet to near-infrared regions.
• To provide a feasible route for constructing high-performance broadband photodetector arrays using a single material.

Main Methods:

• Fabrication of a 3x5 photodetector array using few-layer MoTe2.
• Growth of MoTe2 via chemical vapor deposition (CVD).
• Characterization of the photodetector's photoresponse, responsivity, external quantum efficiency, detectivity, and response/recovery times.

Main Results:

• The MoTe2 photodetector array demonstrated a stable photoresponse across the ultraviolet to near-infrared spectrum.
• Key performance metrics include responsivity (R) of 3.82 mA W⁻¹, external quantum efficiency of 1.17%, and detectivity (D*) of 1.62 × 10⁷ Jones at 405 nm.
• The device exhibited millisecond-scale response and recovery times across its entire photoresponse range.

Conclusions:

• Few-layer MoTe2 grown by CVD is a promising material for high-performance broadband photodetector arrays.
• The developed array offers a scalable and effective solution for applications requiring broad spectral sensitivity and fast response.
• This work paves the way for single-material-based broadband photodetector array construction.