E-beam damage

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This is especially true if the sample has been subjected to high e-beam currents used for X-ray mapping, CL and BSE imaging. The resulting isolated grain can be unsuitable for further analytical measurements, and so the resilience of the resin to e-beam impact can be an important parameter in determining the resin to use.

Sample preparation

Samples of 13 resins were mounted in individual 25mm diameter, 5mm deep, Al-rings. The three Beuhler hot press resins; TransOptic, ProbeMet and KonductoMet were mounted without the Al-rings.

The mounts were then ground using Beuhler UltraPrep nickel bonded diamond 74 micron and 20 micron discs followed by 1200 and 2500 silicon carbide paper. They were polished with 3 micron diamond for 15 minutes and then with 0.3 micron Al-oxide for 10 minutes, washed and then ultrasonically cleaned with 10% Decon 90. The samples were finally cleaned with ethanol before carbon coating using a Deton coater to produce a thin conducting film across the sample surface.

Measurement Procedure

The epoxy resins were carbon-coated before being loaded into the Scanning Electron Microscope. The electron beam was adjusted to have a current of 5nA, 20Kv and scanned an area at 5000x magnification for 10 minutes. The size and depth of the resulting raster pits were measured using the Tencor alpha-step 200 profilometer.

KonductoMet and ProbeMet were both too heterogeneous to produce a distinct raster pit, while TransOptic blistered under the beam showing a positive profile in comparison to the pits produced in the other samples.