All‐Organic and Fully‐Printed Semitransparent Photodetectors Based on Narrow Bandgap Conjugated Molecules

Abstract

All-organic, fully-printed and semitransparent photodetectors with a broad wavelength band response, based on a ternary blend comprising narrow band-gap small molecules, are demonstrated. The ternary blend with a semiconducting polymer allows for the optimal printing of small molecules, suppressing strong phase segregation, and uncontrolled crystallization. The insertion of a suitable interlayer enables the adoption of polymer, transparent, top and bottom printed electrodes, thus making light detection possible from both device sides.

Spray coated indium-tin-oxide-free organic photodiodes with PEDOT:PSS anodes

“…A lower electric field leads to a lower average carrier velocity, hence, at the same time both the velocity is lower and the travel distance is higher: it follows that with an increasing thickness of the layers, the carrier average travel time is increased, with a consequent reduction of the highest 27 ≈ 100 32 (−1 V bias) 10 −3 Inkjet Azzellino et al 28 ≈ 10000 65 (−0,9V bias) 10 −3 Inkjet Baierl et al 19 ≈ 100000 70 (−4V bias) 10 −5 Spray/inverted Falco et al 29 ≈ 100000 65 (−5V bias) 10 −4 Spray/CNT This work ≈ 100000 59 (−4V bias) 10 −4 Spray possible operating frequencies. As mentioned above photodiodes optimized in order to achieve a high on-off ratio are limited in their dynamic response, which reduces their field of application to stationary ones.…”

Organic Photodiodes: The Future of Full Color Detection and Image Sensing

“…While many molecular materials are processed by evaporation, [ 105 ] there are examples whereby they are solution processed. [ 37,106 ] Macromolecules such as dendrimers and polymers can be processed from solution using techniques such as aerosol-jet printing, [ 107 ] spin-coating, [ 108 ] inkjet-printing, [ 109,110 ] screen printing, [ 111 ] or spray-coating. [112][113][114][115] …”

Inkjet Printed Single‐Walled Carbon Nanotube Based Ambipolar and Unipolar Transistors for High‐Performance Complementary Logic Circuits

“…[3][4][5][6][7][8] Different solution-processable semiconductors are being developed and tested in fi eld-effect transistors (FETs), among which conjugated small-molecule and polymer semiconductors are one of the most investigated approaches. [9][10][11][12][13][14] Alternative carbon based and solution-processable semiconductors, such as single-walled carbon nanotubes (SWCNT), [ 15 ] are being also strongly explored because they offer a path towards high performance in terms of charge mobility and electronic bandwidth of printed FETs thanks to their intrinsic electronic properties.…”