Highly conducting, transparent, and flexible indium oxide thin film prepared by atomic layer deposition using a new liquid precursor Et2InN(SiMe3)2.

Highly conductive indium oxide films, electrically more conductive than commercial sputtered indium tin oxide films films, were deposited using a new liquid precursor Et2InN(SiMe3)2 and H2O by atomic layer deposition (ALD) at 225-250 °C. Film resistivity can be as low as 2.3 × 10(-4)-5.16 × 10(-5) Ω·cm (when deposited at 225-250 °C). Optical transparency of >80% at wavelengths of 400-700 nm was obtained for all the deposited films. A self-limiting ALD growth mode was found 0.7 Å/cycle at 175-250 °C. X-ray photoelectron spectroscopy depth profile analysis showed pure indium oxide thin film without carbon or any other impurity. The physical and chemical properties were systematically analyzed by transmission electron microscopy, electron energy loss spectroscopy, X-ray diffraction, optical spectrometer, and hall measurement; it was found that the enhanced electrical conductivity is attributed to the oxygen deficient InOx phases.

Dendron-modified polystyrene microtiter plate: surface characterization with picoforce AFM and influence of spacing between immobilized amyloid beta proteins.

A polystyrene microtiter plate was coated with a molecular layer of a cone-shaped dendron as a means of providing proper spacing between immobilized biomolecules. For the coating preparation, di(ethylene glycol) vinyl ether was grafted onto the surface of the microtiter plate by a plasma process followed by self-assembly of a second-generation dendron (9-acid) or a third-generation dendron (27-acid). Contact angle analysis revealed a pronounced increase in the hydrophilicity upon plasma grafting, while the hydrophilicity reverted/decreased after dendron immobilization. For analysis by force-based atomic force microscopy (AFM), oligonucleotides were immobilized onto the AFM tip and the plate. The DNA-DNA interaction was observed at all spots examined, which implied that coating of the dendrons was uniform over the entire surface. The effectiveness for biomolecular assays of the spacing on dendron-modified microtiter plates was examined by carrying out an enzyme-linked immunosorbent assay (ELISA), where enhanced detection of different fragments of amyloid beta protein (A beta) was observed when compared with other conventional plates, such as untreated polystyrene or maleic anhydride activated plates. The positive influence of the mesospacing between biomolecules on the microtiter plates for this assay was confirmed.