High‐Detectivity All‐Polymer Photodetectors with Spectral Response from 300 to 1100 nm

Abstract

Broad‐response and high‐detectivity for all‐polymer photodetectors based on p‐ and n‐type semiconducting polymers have been achieved through optimization of polymer property and film microstructure. The electron‐donating units in the p‐type polymers affect a great deal of the polymer properties such as solubility, absorption spectra, and electronic energy levels, which in turn can influence the device performance. The polymer (P3) based on dithienopyrrole and diketopyrrolopyrrole is most promising for photodetector applications, as it possesses the suitable energy level with regard to the n‐type polymer and exhibits appropriate film morphology and molecular stacking with aid of 1,8‐diiodooctane as an additive during film processing. The photodetector based on P3/poly{[N,N′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)} (PNDI) exhibits good response from 300 to 1100 nm and nearly constant detectivity (D*) above 1012 Jones at 330–980 nm, rendering a great potential of all‐polymer photodetectors for practical applications.

Panchromatic All‐Polymer Photodetector with Tunable Polarization Sensitivity

“…While erroneous, this method allows for a comparison to other detectors reported in the literature that use this method. Under this view, the performance of the polarized detectors compare well to other all‐polymer organic photodetectors, and other intrinsic polarized detectors …”

“…The performance of all‐polymer photovoltaics have also been improving recently with the development of new donor–acceptor copolymers . However, the focus of all‐polymer photovoltaics has largely been on solar power, and there have been limited reports of all‐polymer photodiodes, due primarily to the relatively nascent state of the field …”

Organic Photodetectors and their Application in Large Area and Flexible Image Sensors: The Role of Dark Current

“…However, a trade‐off between J d and the maximum absorption wavelength of the photoactive layer is reached, given the need for a suitably shallow donor polymer LUMO that facilitates exciton separation under illumination and ensures a high open circuit voltage ( V oc ). If the LUMO of the donor is too deep, this would cause inefficient exciton separation and thus low responsivity . Optimal energetic offset in the order of ≈ 0.2–0.3 eV is necessary to achieve CT from donor to acceptor .…”

Flexible Near‐Infrared Plastic Phototransistors with Conjugated Polymer Gate‐Sensing Layers

“…In this regard, organic materials have been tried for the fabrication of NIR detectors with a device geometry of diode or transistor. Most NIR‐sensing organic materials have π‐conjugated structures such as poly(N‐alkyl diketopyrrolopyrrole dithienylthieno[3,2‐b]thiophene (DPP‐DTT), poly(5,7‐bis(4‐decanyl‐2‐thienyl)‐thieno(3,4‐b)diathiazole‐thiophene‐2,5) (PDDTT), bis(2‐oxoindolin‐3‐ylidene)‐benzodifuran‐dione (BIBDF)‐based low bandgap polymer (PBIBDF‐TT), poly[4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐ b ;3,4‐ b ;3,4‐ b ′]dithiophene‐2,6‐diyl‐ alt ‐2,1,3‐benzothiadiazole‐4,7‐diyl] (PCPDTBT), ester group modified polythieno[3,4‐b]thiophene (PTT), and 4,4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY‐BF2) …”