Pentacene

About: Pentacene is a research topic. Over the lifetime, 5051 publications have been published within this topic receiving 161481 citations. The topic is also known as: 2,3:6,7-dibenzanthracene & benzo[b]naphthacene.

Acenes generated from precursors and their semiconducting properties.

Abstract: Acenes are a class of aromatic hydrocarbons composed of linearly fused benzene rings. Noteworthy features of these molecules include their extended flat structure and the narrow gap between the HOMO and LUMO energy levels. However, the preparation of larger acenes, those that are larger than pentacene, has been challenging. These molecules are relatively unstable and have low solubility in typical solvents. Recently researchers have developed a new synthesis route for higher acenes using stable and soluble “precursors,” which generate these structures on demand by either heating or irradiation of light. Using this method, nonsubstituted hexacene, heptacene, octacene, and nonacene were successfully prepared.In this Account, we summarize the preparation of nonsubstituted acenes from corresponding precursors, describe their physical properties, and discuss potential applications including potential usage in organic semiconductor devices. We first introduced the concept of using a precursor in the work with p...

Deep-level defect characteristics in pentacene organic thin films

Abstract: Organic thin-film transistors using the pentacene as an active electronic material have shown the mobility of 0.8 cm2/V s and the grains larger than 1 μm. To study the characteristics of electronic charge concentrations and the interface traps of the pentacene thin films, the capacitance properties were measured in the metal/insulator/organic semiconductor structure device by employing the capacitance–voltage and deep-level transient spectroscopy (DLTS) measurements. Based on the DLTS measurements, the concentrations and the energy levels of hole and electron traps in the obtained pentacene films were formed to be approximately 4.2×1015 cm−3 at Ev+0.24 eV, 9.6×1014 cm−3 at Ev+1.08 eV, 6.5×1015 cm−3 at Ev+0.31 eV and 2.6×1014 cm−3 at Ec−0.69 eV.

Low-Voltage, High-Performance Organic Field-Effect Transistors with an Ultra-Thin TiO2 Layer as Gate Insulator

Abstract: We report on our latest improvements in organic field-effect transistors (OFETs) using ultra-thin anodized gate insulators. Anodization of titanium (Ti) is an extremely cheap and simple technique to obtain high-quality, very thin (∼ 7.5 nm), pinhole-free, and robust gate insulators for OFETs. The anodized insulators have been tested in transistors using pentacene and poly(triarylamine) (PTAA) as active layers. The fabricated devices display low-threshold, normally “off” OFETs with negligible hysteresis, good carrier mobility, high gate capacitance, and exceptionally low inverse subthreshold slope. Device performance is improved via chemical modification of TiO2 with an octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM). As the result of this combination of favorable properties, we have demonstrated OFETs that can be operated with voltages well below 1 V.

Moisture induced electron traps and hysteresis in pentacene-based organic thin-film transistors

Abstract: Previous work revealed that electron traps in pentacene formed in air cause hysteresis in thin-film transistor characteristics Here, we experimentally showed that water vapor, rather than oxygen, is responsible for these hysteresis-causing trap states Photogenerated and injected electrons are trapped at the pentacene-dielectric interface under positive gate bias, and induce extra holes, resulting in the observed extra drain current The electron detrapping causes the decay of the extra hole population with time under negative gate bias and, therefore, that of the drain current