Research in the use of organic polymers as the active semiconductors in light-emitting diodes has advanced rapidly, and prototype devices now meet realistic specifications for applications. These achievements have provided insight into many aspects of the background science, from design and synthesis of materials, through materials fabrication issues, to the semiconductor physics of these polymers.

Electroluminescence in conjugated polymers

Organic thin-film transistors (OTFTs) have lived to see great improvements in recent years. This review presents new insight into conduction mechanisms and performance characteristics, as well as opportunities for modeling properties of OTFTs. The shifted focus in research from novel chemical structures to fabrication technologies that optimize morphology and structural order is underscored by chapters on vacuum-deposited and solution-processed organic semiconducting films. Finally, progress in the growing field of the n-type OTFTs is discussed in ample detail. The Figure, showing a pentacene film edge on SiO2, illustrates the morphology issue.

Organic Thin Film Transistors for Large Area Electronics

An all-polymer semiconductor integrated device is demonstrated with a high-mobility conjugated polymer field-effect transistor (FET) driving a polymer light-emitting diode (LED) of similar size. The FET uses regioregular poly(hexylthiophene). Its performance approaches that of inorganic amorphous silicon FETs, with field-effect mobilities of 0.05 to 0.1 square centimeters per volt second and ON-OFF current ratios of >10 6 . The high mobility is attributed to the formation of extended polaron states as a result of local self-organization, in contrast to the variable-range hopping of self-localized polarons found in more disordered polymers. The FET-LED device represents a step toward all-polymer optoelectronic integrated circuits such as active-matrix polymer LED displays.

https://science.sciencemag.org/content/sci/280/5370/1741.full.pdf

Integrated Optoelectronic Devices Based on Conjugated Polymers

Electron and ambipolar transport in organic field-effect transistors.

Synthetic Principles for Bandgap Control in Linear pi-Conjugated Systems.

Metal-insulator-semiconductor field-effect transistors have been fabricated from polymer semiconductors that can be processed from solution. The performance of these transistors is sufficient to allow the construction of simple logic gates that display voltage amplification. Successful coupling of these gates into ring oscillators demonstrates that these logic gates can switch subsequent gates and perform logic operations. The ability to perform logic operations is an essential requirement for the use of polymer-based transistors in low-cost low-end data storage applications.

https://science.sciencemag.org/content/sci/270/5238/972.full.pdf

Logic Gates Made from Polymer Transistors and Their Use in Ring Oscillators

Metal‐insulator‐semiconductor field‐effect transistors have been constructed with pentacene as the active semiconductor. The pentacene is processed by spin coating from a soluble precursor. A simple thermal conversion yields transistors with carrier mobilities as high as 9×10−3 cm2 V−1 s−1 and current modulations of the order of 105. Depletion of charge is essential to the device operation. Data for an invertor exhibiting voltage amplification are presented.

Precursor route pentacene metal-insulator-semiconductor field-effect transistors

A universal relation between conductivity and field-effect mobility in doped amorphous organic semiconductors

https://pure.tue.nl/ws/files/2150205/587934.pdf

Large induced optical activity in the conduction band of polyaniline doped with (1S)-(+)-10-camphorsulfonic acid

The synthesis, characterization and several properties of water-soluble polysquaraine and polycroconaine are presented. The optical band gap of a film of the polycroconaine 4 amounts to 0.7 eV, equal to the photoconductivity band-gap.

Anita Pomp

Papers

Logic Gates Made from Polymer Transistors and Their Use in Ring Oscillators

Precursor route pentacene metal-insulator-semiconductor field-effect transistors

A universal relation between conductivity and field-effect mobility in doped amorphous organic semiconductors

Large induced optical activity in the conduction band of polyaniline doped with (1S)-(+)-10-camphorsulfonic acid

Water-soluble polysquaraines and polycroconaines