(Georgia Institute of Technology, 2008-07-07)
Kim, P.; Domercq, Benoit; Jones, Simon C.; Hotchkiss, Peter J.; Marder, Seth R.; Kippelen, Bernard; Perry, Joseph W.; Zhang, Xiaohong
We report on solution-processible high permittivity nanocomposite gate insulators based on BaTiO₃ nanoparticles, surface-modified with a phosphonic acid, in poly(4-vinylphenol) for organic field-effect transistors. The use of surface-modified BaTiO₃ nanoparticles affords high quality nanocomposite thin films at large nanoparticle volume fractions (up to 37 vol %) with a large capacitance density and a low leakage current (10⁻⁸ A/cm²). The fabricated pentacene field-effect transistors using these nanocomposites show a large on/off current ratio (I on/off 10 ⁴- 10 ⁶) due to the high capacitance density and small leakage current of the gate insulator.
(Georgia Institute of Technology, 2007-11)
Tay, Savaş; Thomas, Jayan; Momeni, Babak; Askari, Murtaza; Adibi, Ali; Hotchkiss, Peter J.; Jones, Simon C.; Marder, Seth R.; Norwood, Robert A.; Peyghambarian, Nasser
Infiltration of planar two-dimensional silicon photonic crystals with nanocomposites using a simple yet effective melt processing technique is presented. The nanocomposites that were developed by evenly dispersing functionalized TiO₂ nanoparticles into a photoconducting polymer were completely filled into photonic crystals with hole sizes ranging from 90 to 500 nm. The infiltrated devices show tuning of the photonic band gap that is controllable by the adjustment of the nanoparticle loading level. These results may be useful in the development of tunable photonic crystal based devices and hybrid light emitting diodes and solar cells.