Biological specimen preparation for transmission electron microscopy

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

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Transmission Electron Microscopy of an Aluminum-Silver-Stainless Steel Solid State Bond

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117832 ◽

1985 ◽

Vol 43 ◽

pp. 172-173

Author(s):

M. J. Carr ◽

J. F. Shewbridge ◽

T. O. Wilford

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Solid State ◽

Specimen Preparation ◽

Dimensional Control ◽

Tem Analysis ◽

Metal Parts ◽

Dissimilar Metal ◽

Transmission Electron ◽

Short Time

Strong solid state bonds are routinely produced between physical vapor deposited (PVD) silver coatings deposited on sputter cleaned surfaces of two dissimilar metal parts. The low temperature (200°C) and short time (10 min) used in the bonding cycle are advantageous from the standpoint of productivity and dimensional control. These conditions unfortunately produce no microstructural changes at or near the interface that are detectable by optical, SEM, or microprobe examination. Microstructural problems arising at these interfaces could therefore easily go undetected by these techniques. TEM analysis has not been previously applied to this problem because of the difficulty in specimen preparation. The purpose of this paper is to describe our technique for preparing specimens from solid state bonds and to present our initial observations of the microstructural details of such bonds.

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Transmission Electron Microscopy (TEM) Specimen Preparation Technique using Focused Ion Beam (FIB): Application to Material Characterization of Chemical Vapor Deposition of Tungsten (W) and Tungsten Silicides (WSix)

ISTFA 1997: Conference Proceedings from the 23rd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa1997p0237 ◽

1997 ◽

Author(s):

K. Doong ◽

J.-M. Fu ◽

Y.-C. Huang

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Focused Ion Beam ◽

Ion Beam ◽

Chemical Vapor ◽

Specimen Preparation ◽

Preparation Technique ◽

Transmission Electron

Abstract The specimen preparation technique using focused ion beam (FIB) to generate cross-sectional transmission electron microscopy (XTEM) samples of chemical vapor deposition (CVD) of Tungsten-plug (W-plug) and Tungsten Silicides (WSix) was studied. Using the combination method including two axes tilting[l], gas enhanced focused ion beam milling[2] and sacrificial metal coating on both sides of electron transmission membrane[3], it was possible to prepare a sample with minimal thickness (less than 1000 A) to get high spatial resolution in TEM observation. Based on this novel thinning technique, some applications such as XTEM observation of W-plug with different aspect ratio (I - 6), and the grain structure of CVD W-plug and CVD WSix were done. Also the problems and artifacts of XTEM sample preparation of high Z-factor material such as CVD W-plug and CVD WSix were given and the ways to avoid or minimize them were suggested.

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