OPTO-EDU A63.7069, Инструкция по эксплуатации

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atmosphere. Thus, when cleaning electron optics path, there is no need to disassemble the
condenser lens; but only take out the liner for cleaning, and then replace the aperture which
is installed under the bottom of the liner. When cleaning, the liner should be drawn out from
the top of optical path.
1.2.2.4. Column Isolation Valve (V1)
❖
Column V1 is a manually operated vacuum valve, which is installed between condenser lens
and objective lens. This valve separates column from chamber. So, when replacing specimen,
the chamber is in atmosphere, the column can still keep in vacuum state. When opening V1
valve, the high voltage interlock function is started at the same time.
1.2.2.5. Objective Lens
❖
Objective lens is asymmetrical, with long working distance, low spherical aberration and small
magnetic leakage. The bottom pole piece of objective lens can be dismounted without any
influence on original state of scanning coil.
❖
The final apertures are installed between top and bottom pole piece of objective lens. Three
apertures can be installed in the final aperture holder, diameter of aperture is usually 100
μ m
or 200 μ m (customers can choose other diameters according to actual needs). The X-direction
and Y-direction adjusting devices of final aperture are installed on right front of the chamber.
The adjusting device can help users to select final aperture according to actual needs and align
it with electron beam. The final aperture influences depth of focus, resolution and electron
beam current.
1.2.2.6. Scanning Coil Assembly
❖
Scanning coil assembly is installed inside of objective lens to make the electron beam deflect
on the surface of specimen along X direction and Y direction.
❖
When observing images at high magnification, the operator usually needs to move the ROI
(region of interest) image. This can be completed by scan shift, which is realized by
changing DC level on scanning coil X and Y.
1.2.2.7. Stigmator
❖
The stigmator is installed inside of the scanning coil assembly and can correct astigmatism
quickly.
❖
The adjustment of stigmator is realized by the software.
1.2.2.8. Electron Detector
❖
Electron detector of can collect low-energy secondary electrons (SE). A positive voltage
biased on the collect grid which is mounted in front of detector, can attract low-energy SE to
detector. A positive 12KV potential biased on the scintillator accelerates SE. The photon
produced by scintillator enters into the window of photomultiplier, and output video signal.
1.2.2.9. Accessories
❖
Standard accessories which can be installed on A63.7069 are X-Ray Energy Dispersive
spectrometer (EDS), X-ray wave dispersive spectrometer,
Cathodoluminescence
spectrometer, etc. Currently, EDS is the most popular accessory of SEM.
❖
EDS consists of detector and analysis system, which can realize the identification and
quantification of the specimen.