Modification of the Poly(bisdodecylquaterthiophene) Structure for High and Predominantly Nonionic Conductivity with Matched Dopants.

Four p-type polymers were synthesized by modifying poly(bisdodecylquaterthiophene) (PQT12) to increase oxidizability by p-dopants. A sulfur atom is inserted between the thiophene rings and dodecyl chains, and/or 3,4-ethylenedioxy groups are appended to thiophene rings of PQT12. Doped with NOBF4, PQTS12 (with sulfur in side chains) shows a conductivity of 350 S cm, the highest reported nonionic conductivity among films made from dopant-polymer solutions.

ZT > 0.1 Electron-Carrying Polymer Thermoelectric Composites with In Situ SnCl Microstructure Growth.

growth of the common element compound SnCl reaches power factor of 50-100 μW m K, the highest purely n-type polymer composite power factor yet reported. The composite has a gigantic Seebeck coefficient between -4000 and -5000 μV K, many times higher than other polymer composites.

Reducing leakage currents in n-channel organic field-effect transistors using molecular dipole monolayers on nanoscale oxides.

Leakage currents through the gate dielectric of thin film transistors remain a roadblock to the fabrication of organic field-effect transistors (OFETs) on ultrathin dielectrics. We report the first investigation of a self-assembled monolayer (SAM) dipole as an electrostatic barrier to reduce leakage currents in n-channel OFETs fabricated on a minimal, leaky ∼10 nm SiO2 dielectric on highly doped Si. The electric field associated with 1H,1H,2H,2H-perfluoro-octyltriethoxysilane (FOTS) and octyltriethoxysilane (OTS) dipolar chains affixed to the oxide surface of n-Si gave an order of magnitude decrease in gate leakage current and subthreshold leakage and a two order-of-magnitude increase in ON/OFF ratio for a naphthalenetetracarboxylic diimide (NTCDI) transistor.

Effects of pulsing and interfacial potentials on tellurium-organic heterostructured films.

Polycrystalline thin films of tellurium and organic semiconductor molecules are paired in heterostructured field-effect transistors built on Si/SiO2 substrates. While charge carrier mobilities can exceed 1 cm(2)/(V s), there is only a limited gate voltage range over which the current is modulated. We employ continuous and pulsed measurements on transistors to explore the influence of charge equilibration time on device behavior, finding that pulsed gating improves output characteristics.

Tellurium thin films in hybrid organic electronics: morphology and mobility.

Elemental Te displays a wide variety of nanoscale morphologies of vapor-deposited films, depending on the substrate surface and temperature. These morphologies are correlated to field-effect mobilities in transistors made with Te as the lone semiconductor or from Te-organic multilayer semiconductors. Two examples of morphologies and transistor output characteristics, i.