Thin Film Fabrication and Characterization of Layered Rock Salt LiCoO2 on Quartz Glass Spray-Coated with an Aqueous Ammonia Solution Involving Metal Acetates

A LiCoO2 thin film on a quartz glass substrate was fabricated by a wet process involving heat treatment of a precursor film spray-coated with an aqueous ammonia solution containing LiCH3COO and Co(CH3COO)2. The precursor film formed onto the substrate at 180 °C in air, and was heat treated at 500 °C in air for 0.5 h. The obtained film was spin-coated further with an ethanol-based precursor solution containing identical metal acetates, and heat treated at 500 °C in air for 0.5 h. The X-ray diffraction pattern of the resultant film showed only peaks assignable to the layered-rock-salt LiCoO2. Raman spectroscopy measurements revealed vibrational modes assignable to layered rock salt LiCoO2, with minor content of less than 5 mol% of spinel-type Co3O4. The field emission scanning electron microscopy images indicated that the resultant film was 0.21 μm thick, had no voids, and was a combination of small rounded grains measuring 18 nm in diameter and hexagonal grains larger than 0.2 μm in length. The Hall effect measurements indicated that the resultant thin film was a p-type semiconductor with electrical resistivity of 35(2) Ω·cm and a carrier concentration and carrier mobility of 8(2) × 1016 cm−3 and 2(1) cm2·V−1·s−1, respectively.

Chronotopic Ghosts and Quiet Men: José Luis Guerín’s Innisfree

In 1988 José Luis Guerín took a film crew from Spain to the western coast of Ireland, in search of the filming locations of John Ford’s The Quiet Man (1952). The resultant film, Innisfree (1990), blends documentary with fiction, and the present with the past, to seemingly uncover the physical, cultural and spectral remnants of the Hollywood production in this small rural locality. Innisfree is both the product of a journey (the Spanish filmmaker’s fannish field trip) and the representation of several journeys and returns. This essay examines Guerín’s depiction of the ghostly persistence of The Quiet Man in the landscape, by using Mikhail Bakhtin’s concept of the chronotope to identify the lasting significance of real and imagined time-spaces in the cinematic landscape. Just as immigrant Irishman Sean Thornton (John Wayne) returns to his spiritual homeland from Pittsburgh, USA to reclaim his family land, Ford himself returns to the land of his parents’ birth. In Innisfree Thornton’s, Ford’s and Guerín’s imagined Irelands all mingle and intertwine in a confusing crossroads of time, fiction, memory and landscape.

Highly-Conductive and Well-Adhered Cu Thin Film Fabricated on Quartz Glass by Heat Treatment of a Precursor Film Obtained Via Spray-Coating of an Aqueous Solution Involving Cu(II) Complexes

A Cu thin film on a quartz glass substrate was fabricated by a wet process involving heat-treatment of a precursor film spray-coated with an aqueous ammonia solution containing Cu(HCOO)2∙4H2O and Cu(II) complex of ethylenediamine-N,N,N′N′-tetraacetic acid. The precursor film that formed on the substrate at 180 °C in air was heat-treated at 350 °C and post annealed at 400 °C by placing an identical-sized glass on top, under Ar gas flow in a tubular furnace. X-ray diffraction pattern of the resultant film showed only peaks of Cu. The resultant film of 100 nm thickness has an adhesion strength and electrical resistivity of 37(7) MPa and 3.8(6) × 10−5 Ω cm, respectively. The images of atomic force and field-emission scanning-electron microscopies revealed a film of well-connected Cu grains with an average surface roughness of 11 nm. The reflectance of the thin film is more than 90% in the far-infrared region. The film’s chemical composition was also examined by using Auger electron spectroscopy.

Patterned Copper Sulfide Thin Films: a Method for Studying Leaching Behaviour

An experimental study on copper leaching from Cu1.85S thin films is presented, wherein copper extraction is quantitatively evaluated by changes in film thickness measured by white light interferometric profilometry. Changes in the film morphology and elemental composition, as assessed by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy, are used to confirm that the loss in film thickness is due to changes in the copper content and that the resultant film species is consistent with the mechanism of copper dissolution. The Cu1.85S thin films were synthesized by chemical bath deposition. The leaching behaviour of copper from the films was investigated in acidic ferric sulfate media at pHs 1, 2, and 3, and pH 1 at redox potentials of ~350–650 mV versus Ag/AgCl in 3 M KCl. The changes in the film thickness and copper sulfur ratio were shown to reflect copper dissolution behaviour from chalcocite. Leaching of the Cu1.85S films demonstrated a greater decrease in film thickness as pH decreased. In addition comparison of the order of reaction as a function of proton concentration in non-oxidative dissolution of Cu1.85S (0.06) and as a function of iron(iii) concentration in ferric oxidation of Cu1.85S (0.40) shows that the proton dissolution reaction is negligible. Leaching of the Cu1.85S films at redox potentials of up to ~476.4 mV versus Ag/AgCl in 3 M KCl produced covellite and demonstrated greater decreases in film thickness with increases in the redox potential. Leaching of the films above ~476.4 mV resulted in the formation of spionkopite and demonstrated a much lesser decrease in film thickness. These results are consistent with Eh-pH diagrams for the Cu–S–H2O system.

Preparation of Polymer Composite Latex via Miniemulsion Polymerization: Fluorinated Acrylate as Co-Stabilizer and Functional Modifier

The silica/polyacylate composite latex was prepared via miniemulsion polymerization. Fluorinated acrylate monomer was used the co-stabilizer and hydrophobic modifier. The effect of fluorinated acrylate on stability of the composite latex was compared with the traditional co-stabilizer. The composite latex and the resultant film were characterized by Fourier transformation infrared spectroscopy, Dynamic laser scattering, Water contact angle. Fluorinated acrylate can stabilize the miniemulsion polymerization as the co-stabilizer and the resultant film has good durability of hydrophobicity under high moisture environments.

Preparation of Conducting PEDOT/PI Films by Depositing Polymerization of EDOT in Liquid Phase

PI film was suspended in NaOH, FeCl3and EDOT solutions sequentially. The surfaces of the films were analyzed with ATR-FTIR and the surface resistances were measured in four-probe mode. After immersed in NaOH solution amic acids were introduced to the film surface. The hydrolyzed film exhibited better adsorbing property and was able to adsorb FeCl3in g/m2magnitude. As the film with adsorbed FeCl3was suspended in EDOT solution EDOT deposited on the surface and converted to conducting PEDOT. The resultant film exhibited surface resistance about 105Ω and the characteristic absorption bonds of PEDOT on FTIR spectrum.

Performance of CuGaSe2 Solar Cells Grown By Co-Evaporation Process

CuGaSe2 absorber layers were prepared by evaporating elemental Cu, Ga and Se in three stage on Molybdenum coated soda lime glass. The composition of the resultant film was studied by monitoring the substrate temperature, which decreased when a Cu-Se secondary phase was formed. As the Ga supplement increased during the third stage the void that formed in the beginning of the third stage was removed, while a small grain Ga-rich layer was formed on the surface, resulting in a Cu deficient surface. Therefore, the Voc was improved because of the enhanced surface morphology and the Jsc was reduced, due to the Ga rich layer on of the surface. Under optimal conditions, we achieved a cell performance of Voc = 780 mV, Jsc = 12.9 mA/cm2, ff = 62.5 and ν = 7.3 %.

Chemical Structure of N Atoms Incorporated Into 1 nm-thick SiO2/Si as Revealed with the Dissolution and Hydrogenation in Hydrofluoric Acid

ABSTRACTBy detecting vibrational frequencies for N–H structures, the chemical states of N atoms at silicon nitride on silicon, SiN/Si, and silicon oxide with nitrogen on silicon, SiO(N)/Si, systems were deduced after being chemically decollated with H atoms in dilute HF solution. Using the fact that the decollation was associated with the dissolution of these films, we obtained their depth profile. The frequency was increased to an extent of 10 cm-1 by the existence of a thin oxide layer between the SiN layer and the Si substrate. The N–H structure bound to the Si substrate was observed at 3390 cm-1 just before the completely removal of the surface layer. We also observed the NH structure of crystal SiN form, whose frequency was unchanged to be 3325 cm-1. The same technique was applied to detect the chemical structure of the N atoms in an ultra-thin SiO(N) with 5% of the N atoms. The frequency peak of the bulk N structure was observed with that of OH structures. The peak was shifted from 3375 cm-1 to 3405 cm-1 at the interface region, suggesting densification of the film in the interface region. Prior to complete removal, we observed the surface state of the N atoms and the H atoms. Then the frequency of the NH was unaffected by the film formed with the various methods. No SiH structure was observed on the resultant film surface during etching.