Basic Phytotoxicity of Carbon Foils Prepared by Oxidization of Graphite Combined with Fullerene, Fluorine Graphite and Biochar

Scanning electron beam lithography has been used for a number of years to write submicrometer linewidth patterns in radiation sensitive films (resist films) on substrates. On semi-infinite substrates, electron backscattering severely limits the exposure latitude and control of cross-sectional profile for patterns having fundamental spatial frequencies below about 4000 Å(l),Recently, STEM'S have been used to write patterns with linewidths below 100 Å. To avoid the detrimental effects of electron backscattering however, the substrates had to be carbon foils about 100 Å thick (2,3). X-ray lithography using the very soft radiation in the range 10 - 50 Å avoids the problem of backscattering and thus permits one to replicate on semi-infinite substrates patterns with linewidths of the order of 1000 Å and less, and in addition provides means for controlling cross-sectional profiles. X-radiation in the range 4-10 Å on the other hand is appropriate for replicating patterns in the linewidth range above about 3000 Å, and thus is most appropriate for microelectronic applications (4 - 6).

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Quality films from carbon fiber evaporation for thorough coverage of TEM grids

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104157 ◽

1988 ◽

Vol 46 ◽

pp. 418-419

Author(s):

N. Tempel ◽

M. C. Ledbetter

Keyword(s):

Electron Microscopy ◽

High Resolution Electron Microscopy ◽

Carbon Films ◽

Low Noise ◽

Vacuum Evaporation ◽

High Yield ◽

Good Adhesion ◽

Noise Structure ◽

Resolution Electron ◽

Carbon Foils

Carbon films have been a support of choice for high resolution electron microscopy since the introduction of vacuum evaporation of carbon. The desirable qualities of carbon films and methods of producing them has been extensively reviewed. It is difficult to get a high yield of grids by many of these methods, especially if virtually all of the windows must be covered with a tightly bonded, quality film of predictable thickness. We report here a method for producing carbon foils designed to maximize these attributes: 1) coverage of virtually all grid windows, 2) freedom from holes, wrinkles or folds, 3) good adhesion between film and grid, 4) uniformity of film and low noise structure, 5) predictability of film thickness, and 6) reproducibility.Our method utilizes vacuum evaporation of carbon from a fiber onto celloidin film and grid bars, adhesion of the film complex to the grid by carbon-carbon contact, and removal of the celloidin by acetone dissolution. Materials must be of high purity, and cleanliness must be rigorously maintained.

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Investigation of thin sections of biological standards by EDX, EELS, and Auger electron spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013451x ◽

1990 ◽

Vol 48 (2) ◽

pp. 184-185

Author(s):

S. Lehner ◽

H.E. Bauer ◽

R. Wurster ◽

H. Seiler

Keyword(s):

Processing System ◽

Beam Current ◽

Beam Diameter ◽

Thin Sections ◽

Biologically Relevant ◽

Energy Filtering ◽

Low Viscosity ◽

Carbon Foils ◽

Electron Microscopical ◽

Exchange Membrane

In order to compare different microanalytical techniques commercially available cation exchange membrane SC-1 (Stantech Inc, Palo Alto), was loaded with biologically relevant elements as Na, Mg, K, and Ca, respectively, each to its highest possible concentration, given by the number concentration of exchangeable binding sites (4 % wt. for Ca). Washing in distilled water, dehydration through a graded series of ethanol, infiltration and embedding in Spurr’s low viscosity epoxy resin was followed by thin sectioning. The thin sections (thickness of about 50 nm) were prepared on carbon foils and mounted on electron microscopical finder grids.The samples were analyzed with electron microprobe JXA 50A with transmitted electron device, EDX system TN 5400, and on line operating image processing system SEM-IPS, energy filtering electron microscope CEM 902 with EELS/ESI and Auger spectrometer 545 Perkin Elmer.With EDX, a beam current of some 10-10 A and a beam diameter of about 10 nm, a minimum-detectable mass of 10-20 g Ca seems within reach.

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