Electrical Conductivity of Discontinuous Metal Films

High magnification imaging of macromolecules on metal coated biological specimens is limited only by wet preparation procedures since recently obtained instrumental resolution allows visualization of topographic structures as smal l as 1-2 nm. Details of such dimensions may be visualized if continuous metal films with a thickness of 2 nm or less are applied. Such thin films give sufficient contrast in TEM as well as in SEM (SE-I image mode). The requisite increase in electrical conductivity for SEM of biological specimens is achieved through the use of ligand mediated wet osmiuum impregnation of the specimen before critical point (CP) drying. A commonly used ligand is thiocarbohvdrazide (TCH), first introduced to TEM for en block staining of lipids and glvcomacromolecules with osmium black. Now TCH is also used for SEM. However, after ligand mediated osinification nonspecific osmium black precipitates were often found obscuring surface details with large diffuse aggregates or with dense particular deposits, 2-20 nm in size. Thus, only low magnification work was considered possible after TCH appl ication.

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Effects of atmosphere, metal films, temperatures and holding time on the surface topography and electrical conductivity of LiNbO3 single crystals

Ceramics International ◽

10.1016/j.ceramint.2019.02.008 ◽

2019 ◽

Vol 45 (8) ◽

pp. 9736-9753

Author(s):

Jianwei Lian ◽

Jiajia Tao ◽

Xiaojie Chai ◽

Yan Zhang ◽

Anquan Jiang

Keyword(s):

Electrical Conductivity ◽

Surface Topography ◽

Single Crystals ◽

Metal Films ◽

Holding Time

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A New Analytical Expression for the T.C.R. of Thin Monocrystalline Metal Films

ElectroComponent Science and Technology ◽

10.1155/apec.5.209 ◽

1979 ◽

Vol 5 (4) ◽

pp. 209-213 ◽

Cited By ~ 5

Author(s):

C. R. Tellier

Keyword(s):

Electrical Conductivity ◽

Relaxation Time ◽

Reflection Coefficient ◽

Grain Boundary ◽

Metal Film ◽

Approximate Equation ◽

Metal Films ◽

Exact Equation ◽

Temperature Coefficient Of Resistivity ◽

Comparison Of The Results

The analysis of electrical conductivity of continuous thin monocrystalline metal film has been treated by assuming that the scattering from other sources than grain-boundaries can be described by an effective relaxation time. This relaxation time method is applied to the temperature coefficient of resistivity and leads to an analytical approximate equation in terms of the grain-boundary reflection coefficientrand the reduced thicknessk.Comparison of the results with those deduced from the exact equation (derived from the Mayadas and Shatzkes theory) shows that they deviate by less than 5% in largek–,p–, andr– ranges.

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Influence of a Superimposed Film on the Electrical Conductivity of Thin Metal Films

Journal of Applied Physics ◽

10.1063/1.1710078 ◽

1967 ◽

Vol 38 (8) ◽

pp. 3144-3147 ◽

Cited By ~ 47

Author(s):

K. L. Chopra ◽

M. R. Randlett

Keyword(s):

Electrical Conductivity ◽

Metal Films ◽

Thin Metal ◽

Thin Metal Films

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The electrical conductivity of thin metal films at low temperatures

Thin Solid Films ◽

10.1016/0040-6090(72)90154-x ◽

1972 ◽

Vol 13 (1) ◽

pp. 57-60 ◽

Cited By ~ 3

Author(s):

A. Heiman ◽

V. Halpern

Keyword(s):

Electrical Conductivity ◽

Low Temperatures ◽

Metal Films ◽

Thin Metal ◽

Thin Metal Films

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Production of Ultra-Thin Metal Films Using Neutral Cluster Beams

MRS Proceedings ◽

10.1557/proc-206-397 ◽

1990 ◽

Vol 206 ◽

Cited By ~ 3

Author(s):

A. Ramachandra ◽

M. Vaziri ◽

R.P. Andres

Keyword(s):

Thin Films ◽

Electrical Conductivity ◽

Room Temperature ◽

Vacuum Chamber ◽

Metal Films ◽

Gold Clusters ◽

Cluster Beam ◽

Neutral Cluster ◽

Finite Electrical Conductivity ◽

Cluster Beams

ABSTRACTGold clusters (diam. = 1.0 ± .5 nm) are prepared in a gas aggregation source (MECS), expanded into a vacuum chamber to form a neutral cluster beam, and deposited at low impact velocity on room temperature substrates. When several monolayers of these clusters are deposited on clean substrates (nitrocellulose, glass, mica, NaCl), they form smooth ultra-thin films. These cluster-assembled films appear to be similar in quality to those produced by the Takagi-Yamada ion cluster beam process. They exhibit finite electrical conductivity at thicknesses much smaller than is the case with atomically evaporated films. They are extremely uniform and smooth with a surface height that typically varies less than 1 nm across the entire film.

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