Direct anodization–reduction nanomodification of gold films: investigating electrocatalysis of the emerging contaminant halobenzoquinone

Although dynamical diffraction theory was modified for electrons by Bethe in 1928, relatively few calculations have been carried out because of computational difficulties. Even fewer attempts have been made to correlate experimental data with theoretical calculations. The experimental conditions are indeed stringent - not only is a knowledge of crystal perfection, morphology, and orientation necessary, but other factors such as specimen contamination are important and must be carefully controlled. The experimental method of fine-focus convergent-beam electron diffraction has been successfully applied by Goodman and Lehmpfuhl to single crystals of MgO containing light atoms and more recently by Lynch to single crystalline (111) gold films which contain heavy atoms. In both experiments intensity distributions were calculated using the multislice method of n-beam diffraction theory. In order to obtain reasonable accuracy Lynch found it necessary to include 139 beams in the calculations for gold with all but 43 corresponding to beams out of the [111] zone.

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“Preparation of Single Crystalline Gold Films for ED Studies”

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096424 ◽

1972 ◽

Vol 30 ◽

pp. 634-635

Author(s):

Joseph D. C. Peng

Keyword(s):

Crystal Morphology ◽

Diffraction Theory ◽

Scattering Matrix ◽

Vacuum Evaporation ◽

Gold Films ◽

Matrix Formulation ◽

Silver Films ◽

Single Crystalline ◽

Grating Pattern ◽

Stacking Disorder

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

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Hole Formation in Gold Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095807 ◽

1972 ◽

Vol 30 ◽

pp. 510-511

Author(s):

R. W. Vook ◽

R. Cook ◽

R. Ziemer

Keyword(s):

Deposition Rate ◽

Quartz Crystal ◽

Evaporation Rate ◽

Gold Films ◽

Hole Density ◽

Hole Formation ◽

Microscope Slide ◽

Crystal Film ◽

Glass Microscope Slide ◽

Glass Microscope

During recent experiments on Au films, a qualitative correlation between hole formation and deposition rate was observed. These early studies were concerned with films 80 to 1000A thick deposited on glass at -185°C and annealed at 170°C. In the present studies this earlier work was made quantitative. Deposition rates varying between 5 and 700 A/min were used. The effects of deposition rate on hole density for two films 300 and 700A thick were investigated.Au was evaporated from an outgassed W filament located 10 cm from a glass microscope slide substrate and a quartz crystal film thickness monitor. A shutter separating the filament from the substrate and monitor made it possible to obtain a constant evaporation rate before initiating deposition. The pressure was reduced to less than 1 x 10-6 torr prior to cooling the substrate with liquid nitrogen. The substrate was cooled in 15 minutes during which the pressure continued to drop to the mid 10-7 torr range, where deposition was begun.

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On the role of tin underlays for the prevention of thermal grooving in thin gold films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145030 ◽

1986 ◽

Vol 44 ◽

pp. 732-733

Author(s):

Jin Young Kim ◽

R. E. Hummel ◽

R. T. DeHoff

Keyword(s):

Thin Film ◽

Free Surface ◽

Grain Boundary ◽

Beneficial Effect ◽

Failure Mechanism ◽

Failure Mechanisms ◽

Distinct Advantage ◽

Gold Films ◽

Gold Thin Film

Gold thin film metallizations in microelectronic circuits have a distinct advantage over those consisting of aluminum because they are less susceptible to electromigration. When electromigration is no longer the principal failure mechanism, other failure mechanisms caused by d.c. stressing might become important. In gold thin-film metallizations, grain boundary grooving is the principal failure mechanism.Previous studies have shown that grain boundary grooving in gold films can be prevented by an indium underlay between the substrate and gold. The beneficial effect of the In/Au composite film is mainly due to roughening of the surface of the gold films, redistribution of indium on the gold films and formation of In2O3 on the free surface and along the grain boundaries of the gold films during air annealing.

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High-resolution microscopy of twin boundaries in gold

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126202 ◽

1987 ◽

Vol 45 ◽

pp. 260-261

Author(s):

William Krakow ◽

David A. Smith

Keyword(s):

High Resolution ◽

Specimen Preparation ◽

Gold Films ◽

Boundary Area ◽

Transmission Electron ◽

Recent Developments ◽

Tilt Boundaries ◽

High Resolution Microscopy ◽

Twist Boundaries

Recent developments in specimen preparation, imaging and image analysis together permit the experimental determination of the atomic structure of certain, simple grain boundaries in metals such as gold. Single crystal, ∼125Å thick, (110) oriented gold films are vapor deposited onto ∼3000Å of epitaxial silver on (110) oriented cut and polished rock salt substrates. Bicrystal gold films are then made by first removing the silver coated substrate and placing in contact two suitably misoriented pieces of the gold film on a gold grid. Controlled heating in a hot stage first produces twist boundaries which then migrate, so reducing the grain boundary area, to give mixed boundaries and finally tilt boundaries perpendicular to the foil. These specimens are well suited to investigation by high resolution transmission electron microscopy.

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Metal-Assisted Plasma Etching of Silicon: A Liquid-Free Alternative to MACE

10.26434/chemrxiv.6128237 ◽

2018 ◽

Author(s):

Julia Sun ◽

Benjamin Almquist

Keyword(s):

Liquid Phase ◽

Plasma Etching ◽

Chemical Etching ◽

Gold Films ◽

Metallic Films ◽

Au Catalyst ◽

Feed Concentration ◽

Catalytic Activities ◽

Metal Assisted Chemical Etching ◽

Complex Nanostructures

For decades, fabrication of semiconductor devices has utilized well-established etching techniques to create complex nanostructures in silicon. Of these, two of the most common are reactive ion etching in the gaseous phase and metal-assisted chemical etching (MACE) in the liquid phase. Though these two methods are highly established and characterized, there is a surprising scarcity of reports exploring the ability of metallic films to catalytically enhance the etching of silicon in dry plasmas via a MACE-like mechanism. Here, we discuss a metal-assisted plasma etch (MAPE) performed using patterned gold films to catalyze the etching of silicon in an SF6/O2 mixed plasma, selectively increasing the rate of etching by over 1000%. The degree of enhancement as a function of Au catalyst configuration and relative oxygen feed concentration is characterized, along with the catalytic activities of other common MACE metals including Ag, Pt, and Cu. Finally, methods of controlling the etch process are briefly explored to demonstrate the potential for use as a liquid-free fabrication strategy.

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Influence of Annealing on the Structure of Ultrathin Gold Films on the Surface of Glass and CdS Substrates

Journal of Nano- and Electronic Physics ◽

10.21272/jnep.10(5).05011 ◽

2018 ◽

Vol 10 (5) ◽

pp. 05011-1-05011-6

Author(s):

A. B. Danylov ◽

◽

H. A. Ilchuk ◽

R. Yu. Petrus ◽

V. G. Haiduchok ◽

...

Keyword(s):

Gold Films

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Metal–organic frameworks for the removal of the emerging contaminant atenolol under real conditions

Dalton Transactions ◽

10.1039/d0dt03637d ◽

2021 ◽

Vol 50 (7) ◽

pp. 2493-2500

Author(s):

Sara Rojas ◽

Jorge A. R. Navarro ◽

Patricia Horcajada

Keyword(s):

Continuous Flow ◽

Metal Organic Frameworks ◽

Fixed Bed ◽

Emerging Contaminant ◽

Flow Conditions ◽

Metal Organic ◽

Fixed Bed System

A defective Metal-Organic Frameworks as an improved material for the construction of a fixed-bed system working under continuous flow conditions for the removal of the emerging contaminant atenolol.

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