Processing follows function: pushing the formation of self-assembled monolayers to high-throughput compatible time scales.

Self-assembled monolayers (SAMs) of organic molecules can be used to tune interface energetics and thereby improve charge carrier injection at metal-semiconductor contacts. We investigate the compatibility of SAM formation with high-throughput processing techniques. Therefore, we examine the quality of SAMs, in terms of work function shift and chemical composition as measured with photoelectron and infrared spectroscopy and in dependency on molecular exposure during SAM formation.

Printing PPEs: Fundamental Structure-Property Relationships.

A series of differentially alkyl- and alkoxy-substituted poly(-pheneyleneethynylene)s of different molecular weight were prepared and their rheological properties investigated. It was found that the side chain structure of the PPEs of roughly equal molecular weight and degree of polymerization has a significant influence on the rheology and printing behavior of the PPEs. Introduction of branched alkoxy or alkyl substituents improve the printing behavior of the PPEs dramatically.

Investigation of solution-processed ultrathin electron injection layers for organic light-emitting diodes.

We study two types of water/alcohol-soluble aliphatic amines, polyethylenimine (PEI) and polyethylenimine-ethoxylated (PEIE), for their suitability as electron injection layers in solution-processed blue fluorescent organic light-emitting diodes (OLEDs). X-ray photoelectron spectroscopy is used to determine the nominal thickness of the polymer layers while ultraviolet photoelectron spectroscopy is carried out to determine the induced work-function change of the silver cathode. The determined work-function shifts are as high as 1.

The compromises of printing organic electronics: a case study of gravure-printed light-emitting electrochemical cells.

Light-emitting electrochemical cells (LECs) are fabricated by gravure printing. The compromise between device performance and printing quality is correlated to the ink formulation and the printing process. It is shown that the rheological properties of the ink formulations of LECs can be tailored without changing the chemical composition of the material blend.

Inkjet printed, high mobility inorganic-oxide field effect transistors processed at room temperature.

Printed electronics (PE) represents any electronic devices, components or circuits that can be processed using modern-day printing techniques. Field-effect transistors (FETs) and logics are being printed with intended applications requiring simple circuitry on large, flexible (e.g.

Ultraviolet photodetector arrays assembled by dielectrophoresis of ZnO nanoparticles.

Sensitive and fast ultraviolet sensor arrays have been produced by dielectrophoretic assembling of ZnO nanoparticles. The sub-micron device dimensions induce low operating voltage and low power consumption. The devices are long-term stable and operate in air, oxygen and nitrogen.