Red‐Sensitive Image Array Based on Defect‐Engineered PBDB‐T/WSe1.5‐WSe2/Graphene Heterostructure

Abstract

Abstract 2D transitional metal dichalcogenide (TMDC) materials have potential applications in image arrays for electronic eyes that mimick the human visual system. However, as a crucial requirement of the electronic eye, color discrimination is hard to achieve due to the broad absorption band of the TMDCs in the visible region. Here, a red‐sensitive photodetector based on the defect‐engineered WSe2‐Graphene heterostructure covered by PBDB‐T polymers is proposed. The WSe2‐Graphene heterostructure is partially modified by defects generated by the focused ion beam, forming a photovoltaic diode at the boundary of the engineered region. Then, PBDB‐T with optical absorption centered at the wavelength of 624 nm is coated onto the surface of the heterostructure, enhancing the photoresponse of the defect‐engineered WSe2‐Graphene to the red light (633 nm) ten times. Furthermore, a red‐sensitive image array with 6 × 10 pixels is constructed. This work paves a novel avenue for developing the 2D color‐resolvable photodetector array.

Keywords

• 2D heterostructures
• image arrays
• ion beam writing
• photovoltaic detectors