Polymer light-emitting diodes (PLEDs) suffer from inadequate lifetimes because of the use of environmentally sensitive metals as the cathodes. We present the use of water/methanol-soluble polyfluorene grafted with 18-crown-6 chelating to K(+) as the electron-injection layer (EIL) for deep-blue-emission PLEDs, allowing the use of environmentally stable Al as the cathode since electron donation from the 18-crown-6 can reduce K(+) to a stable "pseudometallic state", enabling it to act as an intermediate step for electron injection. Furthermore, when poly(ethylene oxide) was blended into the EIL to provide hole blocking (HB), the device exhibited the highest performance reported to date for a deep-blue-emission PLED based on a conjugated polymer as the emitting layer, with a brightness of 54,800 cd/m(2) and an external quantum efficiency of 5.42%. The use of such an EI-HB layer opens a broad avenue leading toward industrialization of PLEDs.

In microelectronics, silicon dioxide (SiO2) is widely used as an insulator including the gate dielectric, isolation, and passivation layers. Conventional methods of preparing SiO2 films, such as thermal oxidation or CVD techniques, are subject to several problems, such as thermal stress, dopant redistribution, and material interaction. To solve these problems, we suggest replacing conventional techniques with a room-temperature method that grows an SiO2 film with similar quality.Liquid phase deposition (LPD) is a room-temperature method for SiO2 formation. To date, LPD-oxide films have been obtained by adding either H3BO31-5 or A16 to hydrofluosilicic acid (HzSiF~) solution saturated with silica. In this approach, however, owing to the number of additional parameters, the deposition reaction in LPD is complicated. Moreover, this method does not consider the contamination from the chemicals, but rather merely assumes that such contamination is minimal, the LPD method with H20 addition was first attempted by Yoshitomi et al. ~ According to Ref. 5, the chemical reaction for SiO2 growth in the treatment solution can be represented by the following equilibrium reaction ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 169.230.243.252 Downloaded on 2015-03-18 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 169.230.243.252 Downloaded on 2015-03-18 to IP

No abstract

No abstract