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General guidelines
Caution!
1 Begin by placing a bare stub into a sample tray. Never prepare a sample in the
Phenom sample holder for loose particles may end up in the container.
2 Colloidal graphite or silver paint can be used to cement the sample down to the
sample stub. Polymers, insects, and MEMS devices are some examples of samples
that are large enough to affix to a stub using colloidal graphite or silver paint. For
smaller objects like pollen, powders, and TEM grids it is advised to avoid using this
m
ethod as it may submerge the sample before drying.
Also note that once colloidal graphite and silver paint come in to contact with the
sample, they cannot be removed.
For smaller samples, or samples that may need to be removed from the sample stub
after imaging, skip to step 1 of chapter ‘Samples that cannot be prepared in colloidal
graphate or silver paint’.
3 Begin by opening the bottle of graphite or silver paint in a well ventilated area.
4 Take a fine point disposable object such as a toothpick or pin and dip the tip into the
silver paint or graphite. Remove the tip from the liquid and dab the residual graphite
or silver paint onto the bare stub.
5 Replace the lid onto the jar of graphite or silver paint as these will dry out quickly.
6 The liquid will dry quickly so be aware of time during the next three steps.
7 Take the standard tweezers and firmly clamp the sample.
8 Move the sample to a bare area of the stub. Do not place the sample directly into the
liquid.
9 Gently slide the sample into the drop of liquid so that the liquid beads around the
bottom of the sample. Once a desired level or surface contact between the liquid and
sample has been attained, let the liquid dry for 5-10 minutes. The sample is now
ready to image.
4.2.1 Samples that cannot be prepared in colloidal
graphite or silver paint
1 For these samples, a double sided adhesive can be used. Although these adhesive
pads are not quite as conductive as the silver or graphite, they are much easier to use
for a broader spectrum of samples. To begin, peel back the coating on top of the
adhesive with tweezers.
2 Place a clean stub on top of the exposed adhesive. Pull the stub off the adhesive
sheet to expose the other side of the adhesive pad.
3 Now place the sample on top of the exposed adhesive. Make sure the sample is
firmly attached to the stub before placing the sample into the Phenom.
4.2.2 Particle samples
Particles include but are not limited to powders, pollen, small filings, diatomaceous material,
and other dust-like matter.
1 To prepare a particle sample, attach a double sided adhesive pad to a bare sample
stub. See ‘General guidelines’.
2 Take a toothpick, tweezers, or other fine point object and collect some of the particle
sample on the tip. Brush the sample coated tip against the exposed adhesive of the
sample stub. Take the flat side of the toothpick or tweezers and press the particles
firmly against the adhesive pad.
3 Grip the sample with stub holding tweezers and forcibly tap the stub on the side of a
table or bench to remove loose particle from the sample stub.
4 With a can of compressed air, spray the surface of the sample to remove any other
loose particles.
> The sample is now ready to be placed into the Phenom.
5 Repeat steps 3 and 4 when re-imaging a prepared particle sample.