The optoelectronic properties of polymeric semiconductor materials can be utilized for the fabrication of organic electronic and photonic devices. When key structural requirements are met, these materials exhibit unique properties such as solution processability, large charge transporting capabilities, and/or broad optical absorption. In this review recent developments in the area of π-conjugated polymeric semiconductors for organic thin-film (or field-effect) transistors (OTFTs or OFETs) and bulk-heterojunction photovoltaic (or solar) cell (BHJ-OPV or OSC) applications are summarized and analyzed.

π-Conjugated Polymers for Organic Electronics and Photovoltaic Cell Applications†

Electron and ambipolar transport in organic field-effect transistors.

Over the past 20 years, organic transistors have developed from a laboratory curiosity to a commercially viable technology. This critical review provides a short summary of several important aspects of organic transistors, including materials, microstructure, carrier transport, manufacturing, electrical properties, and performance limitations (200 references).

Organic thin-film transistors.

Thin-film electronics in its myriad forms has underpinned much of the technological innovation in the fields of displays, sensors, and energy conversion over the past four decades. This technology also forms the basis of flexible electronics. Here we review the current status of flexible electronics and attempt to predict the future promise of these pervading technologies in healthcare, environmental monitoring, displays and human-machine interactivity, energy conversion, management and storage, and communication and wireless networks.

Flexible Electronics: The Next Ubiquitous Platform

Organic thin-film transistors (OTFTs) offer unprecedented opportunities for implementation in a broad range of technological applications spanning from large-volume microelectronics and optical displays to chemical and biological sensors. In this Progress Report, we review the application of organic transistors in the fields of flexible optical displays and microelectronics. The advantages associated with the use of OTFT technology are discussed with primary emphasis on the latest developments in the area of active-matrix electrophoretic and organic light-emitting diode displays based on OTFT backplanes and on the application of organic transistors in microelectronics including digital and analog circuits.

Organic transistors in optical displays and microelectronic applications

To date there are two demonstrated technologies for the fabrication of organic integrated circuits: the unipolar and the complementary technology. Unipolar architectures consist of p-channel organic field-effect transistors (OFETs), which are simple to fabricate since they require a single, high-workfunction metal (e.g., gold) and a single semiconductor material, which can be either evaporated or solution-processed.[1–4] Despite this great advantage, unipolar circuits have poor performance, exhibiting a narrow noise margin, low yield, and high power consumption.[2] In order to improve their performance, more sophisticated architectures are usually employed.[5] Although beneficial, such an approach increases circuit complexity by nearly 100 %. Complementary architectures, adopted from silicon microelectronics, solve this bottleneck by providing major advantages in circuit performance, including wide noise margin, robustness, and low power dissipation.[6,7] Unlike silicon technology, however, fabrication of discrete organic n- and p-channel transistors with lateral dimensions of a few micrometers, typically required for largescale integration, is still very challenging.

Air-Stable Complementary-like Circuits Based on Organic Ambipolar Transistors†

The x-ray fluorescence intensity of a sample contains the product of two angular-dependent factors: the first describes the angular dependence of the absorption of both incident and emitted radiation and the second is a geometrical factor accounting for the angular variation of irradiated and detected surface area. Theory for the angular dependence of x-ray intensities is presented. Good agreement is found with experimental data, measured with a novel focusing spectrometer using a small silicon detector. Measurement of the angular dependence of intensities is especially promising for the analysis of multi-layer samples.

de Boer

Papers

Air-Stable Complementary-like Circuits Based on Organic Ambipolar Transistors†

Angular dependence of X-ray fluorescence intensities

Die verschiedene Beständigkeit gleichgebauter Hafnium‐ und Zirkoniumkomplexe