scholarly journals DEFECT STUDIES OF THIN LAYERS BY THE VIBRATING-REED TECHNIQUE

1981 ◽  
Vol 42 (C5) ◽  
pp. C5-1111-C5-1122 ◽  
Author(s):  
B. S. Berry ◽  
W. C. Pritchet
Keyword(s):  
Thin Layers ◽  
Vibrating Reed

Study of PPV Polymer Layers on Si Substrates by Mechanical Spectroscopy

2008 ◽  
Vol 137 ◽  
pp. 189-198
Author(s):  
A. Strahl ◽  
Sigurd Schrader ◽  
S. Katholy ◽  
B. Grimm ◽  
Hartmut Neuhäuser
Keyword(s):  
Spin Coating ◽  
Activation Parameters ◽  
Surface Region ◽  
Temperature Cycling ◽  
Thin Layers ◽  
Mechanical Spectroscopy ◽  
Langmuir Blodgett ◽  
Si Substrates ◽  
Polyphenylene Vinylene ◽  
Vibrating Reed

Thin layers of the OLED related polyphenylene-vinylene (PPV) deposited by a precursor on micro-fabricated Si cantilevers were studied by applying the vibrating-reed technique during repeated temperature cycling between 100 and 520 K. By means of the Langmuir-Blodgett method for film production, the dependence of damping and elastic modulus on well defined values of film thickness (16 to 69 nm) was determined. Simultaneous measurements of these quantities showed four damping peaks during heating around 130 K (called γ), 250 K (β), 350 K (β’), and 400 K (called C). Three of them (γ, β’, C) disappeared after heating to the highest temperature (520 K) indicating their presence in the precursor only. The activation parameters of the relaxation peaks (γ, β, β’) were estimated and assigned to specific atomic movements in the molecule. Peak C occurs during the conversion process of precursor to polymer. Earlier results are essentially substantiated, indicating only slight differences to those for layers produced previously by spin coating. The observed thickness dependence of damping for the γ and β peaks suggests a weaker contribution of molecules in the surface region than of those in the bulk, while the β’ peak is supposed to result from molecules in the interface region between layer and substrate.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

EELS Measurement of the Local Electronic Structure of Copper Atoms Segregated to Aluminum Grain Boundaries

1996 ◽  
Vol 54 ◽  
pp. 342-343
Author(s):  
S.J. Splinter ◽  
J. Bruley ◽  
P.E. Batson ◽  
D.A. Smith ◽  
R. Rosenberg
Keyword(s):  
Electronic Structure ◽  
Grain Boundaries ◽  
Boundary Segregation ◽  
Thin Layers ◽  
Nominal Composition ◽  
Spatially Resolved ◽  
Service Lifetime ◽  
Heat Treated ◽  
Probe Size ◽  
Local Electronic Structure

It has long been known that the addition of Cu to Al interconnects improves the resistance to electromigration failure. It is generally accepted that this improvement is the result of Cu segregation to Al grain boundaries. The exact mechanism by which segregated Cu increases service lifetime is not understood, although it has been suggested that the formation of thin layers of θ-CuA12 (or some metastable substoichiometric precursor, θ’ or θ”) at the boundaries may be necessary. This paper reports measurements of the local electronic structure of Cu atoms segregated to Al grain boundaries using spatially resolved EELS in a UHV STEM. It is shown that segregated Cu exists in a chemical environment similar to that of Cu atoms in bulk θ-phase precipitates.Films of 100 nm thickness and nominal composition Al-2.5wt%Cu were deposited by sputtering from alloy targets onto NaCl substrates. The samples were solution heat treated at 748K for 30 min and aged at 523K for 4 h to promote equilibrium grain boundary segregation. EELS measurements were made using a Gatan 666 PEELS spectrometer interfaced to a VG HB501 STEM operating at 100 keV. The probe size was estimated to be 1 nm FWHM. Grain boundaries with the narrowest projected width were chosen for analysis. EDX measurements of Cu segregation were made using a VG HB603 STEM.

Domain structures in thin layers of a ferrocolloid

1993 ◽  
Vol 3 (11) ◽  
pp. 1633-1645 ◽  
Author(s):  
Yu. A. Buyevich ◽  
A. Yu. Zubarev
Keyword(s):  
Thin Layers ◽  
Domain Structures

INTERNAL FRICTION INVESTIGATIONS OF ELECTROLYTICALLY DEPOSITED THIN LAYERS

1983 ◽  
Vol 44 (C9) ◽  
pp. C9-487-C9-492
Author(s):  
G. Haneczok ◽  
R. Kuśka ◽  
R. Kwiatkowski ◽  
J. W. Moro
Keyword(s):  
Internal Friction ◽  
Thin Layers

Electrical Anisotropy of Thin Metal Films Growing on Dielectric Substrates

2002 ◽  
Vol 7 (2) ◽  
pp. 45-52
Author(s):  
L. Jakučionis ◽  
V. Kleiza
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Uniaxial Anisotropy ◽  
Metal Films ◽  
Thin Layers ◽  
Electrical Anisotropy ◽  
Electrical Field ◽  
Dielectric Substrates ◽  
Unequal Probability ◽  
Conductive Thin Films

Electrical properties of conductive thin films, that are produced by vacuum evaporation on the dielectric substrates, and which properties depend on their thickness, usually are anisotropic i.e. they have uniaxial anisotropy. If the condensate grow on dielectric substrates on which plane electrical field E is created the transverse voltage U⊥ appears on the boundary of the film in the direction perpendicular to E. Transverse voltage U⊥ depends on the angle γ between the applied magnetic field H and axis of light magnetisation. When electric field E is applied to continuous or grid layers, U⊥ and resistance R of layers are changed by changing γ. It means that value of U⊥ is the measure of anisotropy magnitude. Increasing voltage U0 , which is created by E, U⊥ increases to certain magnitude and later decreases. The anisotropy of continuous thin layers is excited by inequality of conductivity tensor components σ0 ≠ σ⊥. The reason of anisotropy is explained by the model which shows that properties of grain boundaries are defined by unequal probability of transient of charge carrier.

Injecting Inter-Layers and the Built-in Potential of Blue Polymer Light-Emitting Diodes

2000 ◽  
Vol 660 ◽  
Author(s):  
Thomas M. Brown ◽  
Ian S. Millard ◽  
David J. Lacey ◽  
Jeremy H. Burroughes ◽  
Richard H. Friend ◽  
...  
Keyword(s):  
Indium Tin Oxide ◽  
Light Emitting Diodes ◽  
Basic Structure ◽  
Thin Layers ◽  
Carrier Injection ◽  
Semiconducting Polymer ◽  
Light Emitting ◽  
Physical Mechanisms ◽  
Organic Solid ◽  
Polymer Light Emitting Diodes

ABSTRACTThe semiconducting-polymer/injecting-electrode heterojunction plays a crucial part in the operation of organic solid state devices. In polymer light-emitting diodes (LEDs), a common fundamental structure employed is Indium-Tin-Oxide/Polymer/Al. However, in order to fabricate efficient devices, alterations to this basic structure have to be carried out. The insertion of thin layers, between the electrodes and the emitting polymer, has been shown to greatly enhance LED performance, although the physical mechanisms underlying this effect remain unclear. Here, we use electro-absorption measurements of the built-in potential to monitor shifts in the barrier height at the electrode/polymer interface. We demonstrate that the main advantage brought about by inter-layers, such as poly(ethylenedioxythiophene)/poly(styrene sulphonic acid) (PEDOT:PSS) at the anode and Ca, LiF and CsF at the cathode, is a marked reduction of the barrier to carrier injection. The electro- absorption results also correlate with the electroluminescent characteristics of the LEDs.

Ultra-thin layers of phosphorylated cellulose derivatives on metal surfaces

2002 ◽  
Vol 177 (1) ◽  
pp. 97-110 ◽  
Author(s):  
Evelin Jaehne ◽  
Thomas Kowalik ◽  
Hans-Juergen P. Adler ◽  
Andreas Plagge ◽  
Martin Stratmann
Keyword(s):  
Metal Surfaces ◽  
Thin Layers ◽  
Cellulose Derivatives
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