FEI Quanta FEG 250, Руководство пользователя

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System Options: Heating Stage 1000 °C / Heating Stage 1500 °C
9-38
2. Snap the wire hook on the printed circuit board onto the cap.
3. Plug the printed circuit board adapter into the connector on the
chamber ceiling.
4. Press the cap onto the final lens aperture standard insert.
1000 °C Heating Stage variances
Heat Shield
is a small part sitting on the HS assembly top. The heat shield is most
efficient above 600 °C, where the sample is more prone to a radiant
heat loss. In this environment the heat shield creates an “oven” effect
helping to keep the temperature consistent throughout the sample.
Crucibles
Crucibles have a finite lifetime, and are meant to be disposable when
it becomes too contaminated and can no longer be cleaned.
Ceramic crucibles also shrink after some time of use. This could
cause vibrations, if the crucible does not fit tightly in the heater. A
Ceramic paper pad provided with the HS option is used to fix the
crucible. Place the paper (or a part of it) by tweezers between the
heater and the crucible.
• The Standard MgO crucible is used for thin samples and powders.
• The Low MgO crucible is provided for tall or bulky samples (it sits
lower into the heater for more uniform sample heating).
The MgO crucibles can be used for all atmospheres.
• The Graphite crucible are to be used only in an inert or reducing
atmosphere below 900 °C.
1500 °C Heating Stage variance
1500 °C heating stage assembly has a limited lifetime and has not
accurate temperature readings below 800 °C. Because of these
reasons two 1500 °C heating stage assemblies and one 1000 °C
heating stage assembly are supplied within the HS 1000° option.
The inner cable for each stage type is different and marked by a label:
HS 1000 / HS 1500.
Heat Shield Assembly
is attached to an individual feed-through plate. The shield (comprises
multiple layers of aluminous paper supported by netting stainless steel
disks) is attached to the end of the Swing Arm (for a large chamber it
is necessary to use the extender). The
Swing Arm is used to move the
shield away by a knob on the outside of the feed-through plate.
FIGURE 9-32 1500 °C HEAT SHIELD ASSEMBLY (Small Chamber)
Caution:
When the Heat shield is installed, the stage tilt is limited, even if the