High Responsivity and Response Speed Single‐Layer Mixed‐Cation Lead Mixed‐Halide Perovskite Photodetectors Based on Nanogap Electrodes Manufactured on Large‐Area Rigid and Flexible Substrates. (8th May 2019)

• Record Type: Journal Article
• Authors: Georgiadou, Dimitra G.; Lin, Yen‐Hung; Lim, Jongchul; Ratnasingham, Sinclair; McLachlan, Martyn A.; Snaith, Henry J.; Anthopoulos, Thomas D.
• Is Part Of: Advanced functional materials. Volume 29:Number 28(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-05-08
• Subjects: image sensors -- metal halide perovskites -- nanopatterning -- photodiodes; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201901371
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Mixed‐cation lead mixed‐halide perovskites are employed as the photoactive material in single‐layer solution‐processed photodetectors fabricated with coplanar asymmetric nanogap Al–Au and indium tin oxide–Al electrodes. The nanogap electrodes, bearing an interelectrode distance of ≈10 nm, are patterned via adhesion lithography, a simple, low‐cost, and high‐throughput technique. Different electrode shapes and sizes are demonstrated on glass and flexible plastic substrates, effectively engineering the device architecture, and, along with perovskite film and material optimization, paving the way toward devices with tunable operational characteristics. The optimized coplanar nanogap junction perovskite photodetectors show responsivities up to 33 A W −1, specific detectivity on the order of 10 11 Jones, and response times below 260 ns, while retaining a low dark current (0.3 nA) under −2 V reverse bias. These values outperform the vast majority of perovskite photodetectors reported so far, while avoiding the complicated fabrication steps involved in conventional multilayer device structures. This work highlights the promising potential of the proposed asymmetric nanogap electrode architecture for application in the field of flexible optoelectronics. Abstract : Flexible coplanar metal–perovskite–metal photodetectors are fabricated using nanogap‐separated asymmetric electrodes patterned with adhesion lithography. The ultrashort (≈10 nm) interelectrode distance and the carefully engineered perovskite film result in devices exhibiting high responsivity (33 A W −1 ) and fast response times of 260 ns.