EMS Technical Data Sheets

Plasma Chemistry Applied to Electron Microscopy (EM) Preparation Procedures

EMS Catalog #93000

Applications for Plasma Ashing in Electron Microscopy (EM) Preparation Procedures

A selection of published work covering a range of applications using plasma chemistry as a preparation technique.

Replica EM studies of polyamide structure

Use of oxygen plasma for differential etching of ordered and disordered regions in organic specimens. Rates of etching reduced from lower molecular weight substances through disordered (amorphous) regions to ordered (crystalline) regions. This allowed identification by replica EM of simultaneous presence of single crystals and spherilites in Polamide 68.

Replica EM studies of latexes of acrylic copolymers

Using replica EM and oxygen ashing it was shown that latex particles of Polyalkylacrylates and Alkylacrylate-Methacrylic Acid Copolymers are aggregates of primary globules, the size of the globules depends upon the polymer.

EM studies of polyethylene tetraphthalates films and fibers

Oxygen ashing in conjunction with replica EM revealed supra molecular structure with correlation between EM and x-ray diffraction data. Oxygen ashing followed by SEM examination allowed identification of three types of internal flaw in bright fibers. Results showed high concentrations of titanium dioxide in regions containing voids, and highly ordered polymers which had previously been assumed to be defusants.

Quantitative bulk analysis by TEAM of biological microspecimens

100um sections of Wistar rat hearts were oxygen plasma ashed and then dissolved and sprayed onto grids. The droplets were then individually analyzed. The method was found to retain volatiles such as sulphur and possibly chlorine. Ashing times when compared to high temperature ashing are considerably reduced.

Microincineration for EM localization of biological materials

A review of high temperature ashing and plasma ashing of various materials.

Review of techniques for SEM and electron probe microanalysis

Among many applications the following are highlighted: microelectronic failure analysis; grain boundary composition in mineralogical specimens containing silicates and carbonaceous material; discovery if microvoids and flaws in carbon reinforcing fibers; differential etching of polymers; formation of 3D ash skeletons; studies of modular graphite inclusions in cast iron; mineral staining of brain tissue followed by oxygen ashing.

Low temperature ultra microincineration of thin-sectioned tissue

Plasma incineration used to determine the morphological localization of structure bound mineral and metallic elements within biological cells at TEM levels.

Ultrastructure of cell organelles in thick plasma-etched sections

1um sections of fixed and embedded kidney tissue when surface etched by oxygen plasma, allowed etch resistant cell components to be imaged with clarity. Resolution was better that other preparation technique for SEM of internal structures of cells and organelles in bulk specimens of tissue.

TEM-EDS of silica in cell walls of rye grass

A comparison of preparation methods, including plasma ashing, to determine amounts of silicon in cell wall material.

Plasma ashing moths and insects prior to EM and XES

Oxygen ashing of insects allowed the removal of organic material but left the structure intact. This allowed area sectioning for subsequent analysis.

X-ray microanalysis of Epon sections after oxygen plasma ashing

Improved X-ray detectability of elements retained in ash by lowered background counts. Method removes osmium fixative and chlorine to reveal hidden phosphorous peak; pattern fidelity allows micro analytical resolution of 0.1um.

Measuring the concentration of asbestos fibers in air specimens

Oxygen plasma used to remove high levels of airborne organic contaminants and to remove filter paper prior to TEM sizing.

SEM of embedded biological specimens that have been surface plasma etched

As a general technique for SEM, oxygen plasma etching thick sections of a wide variety of different types of embedded tissue yields specimens that show a resolution that is considerably better than that obtainable by most other methods; particularly for viewing internal structure of cells and organelles in bulk structure.

Identification second counting of asbestos fibers on membrane filters

Methods are described whereby asbestos fibers can be counted by phase contrast microscopy and identified on the same membrane filter by optical and SEM techniques. Airborne concentration of different asbestos types in mixed clouds can therefore be estimated.

References

Improved gas-discharge etching techniques in the Electron Microscope studies of Polyamide structures.
L I Bezruk. Vysokomol. Soyed. A10: No. 6 1434-1437, 1968

Particle and film structures of films of some latexes of acrylic copolymers
V I Yeliseyeva. Vosokomol. Soyed A9: No 11 2478-2481, 1967

Oxygen etching method of making an Electron Microscopy study of Polyethylene Tetraphthalate films
K Z Gumargaliveva. Vosokomol. Soyed. 8: No. 10 1742-1744, 1966

Studies of plasma-etched Polyethylene Terephthalate fibres by SEM and energydispersive X Ray microanalysis
P R Blakey & M O Alfy. Letter to Journal of Textile Institute 1978 No 1

Detection of inorganic materials in biological specimens
Source unknown

Microincineration techniques for electron-microscopic localization of biological minerals
Richard S Thomas. W Region Research Lab, Agricultural Research Service, US Dept, of Ag.
Albany Ca. USA

Use of chemically reactive gas plasma in preparing specimens for SEM and Electron Probe Microanalysis
Richard S Thomas. SE.M/1974 part I proc 7th SEM Symph –April/1974

Low temperature ultra-microincineration of thin section tissue
Wayne Hohman & Harold Shraer. Journal of Cell Biology, Volume 55 1972 pp 328-354

Ultra-microincineration of thin-sectioned tissue
Principles and Techniques of EM-1976

Ultrastructure of cell organelles by Scanning Electron Microscopy of thick sections surface-etched by an Oxygen plasma
W J Humphreys. Journal of Microscopy Vol 116 July 1979

Silica in the mesophyll cell walls of Italian Rye Grass
D Dinsdale Ann. Bot 44 73-77 1979

Ashing moths and various insects
J Bowden (pr comm) Rothampstead Research Station. July 1979

X-ray microanalysis of Epon sections after Oxygen plasma microincineration
Tudor Barnard and R S Thomas Journal of Microscopy Vol 113 Pt 3 Aug 1978. pp269-276

Scanning Electron Microscopy of biological specimens surface-etched by an Oxygen plasma
W J Humphreys. Scanning Electron Microscopy 1979/11. Asbestos counting method using
TEM. Ontario Research Foundation.

In situ identification of Asbestos fibres collected on membrane filters for counting
N P Vaugham and S J Rooker. Ann. Occup. Hyg. Vol 24 No 3 pp281-290 1981.

Additional Technical Data Sheets

Plasma Etching and Ashing Principles

Plasma Chemistry

Plasma Asher Applications

Online Ordering

K1050X RF Plasma Asher