Introduction to Operation of the XL30 Scanning Electron Microscope
Tutorial # 2
Introduction to Operation and
Imaging
Remember Purpose
• Purpose of these tutorials is to enable the
user to understand the basics of
OPERATING the XL-30 to obtain Secondary
Electron and Back Scattered Electron
Images, and to obtain an Energy Dispersive
X-Ray Spectrum.
• Very little theory is given.
• If the user’s requirements demand further
instruction, he or she should seek further
formal instruction.
Prepare your sample
• You should have your samples
ready before using the
instrument. Most samples are
mounted on sample stubs like the
one shown on the left.
• If you use Carbon paint or some
other liquid to attach your
sample. LET IT DRY.
• Non-conductive samples usually
must be coated with a conductive
material, e.g., gold, carbon.
Log-In
• You must have an
account set in the CAF
FOM to use this
instrument.
• You should also sign in
the paper copy log book
(until we discontinue).
Overview
The Column and Table Top
• Do not lean on or place
items on the
Microscope table top.
• The top is raised by air
pistons when the
column is under
vacuum. This helps
dampen any external
vibrations that might be
translated to the
sample.
Check Nitrogen
• Nitrogen Gas
– Open the valve on the
bottle.
DO NOT turn the needle
valve on the gauge.
• Liquid Nitrogen (see
Liquid Nitrogen filling
instructions) if you are
going to do EDS
analysis.
Instrument On?
• OFF button should be
illuminated.
• Vacuum button
illuminated.
• High Tension button
may be illuminated.
• The EDAX computer
should also be ON.
Open the XL30 Microscope Control
• Generally the Microscope Control Program is up and
running. If not, open the program from the Windows
Program Manager.
Load Your Sample – 1
• XL Control Program Upper
Right
– “Vacuum” the Pump button
should be yellow meaning the
chamber is under vacuum.
– The Acc. Voltage button
under “Beam” should be gray.
– Left click the Vent button to
start the vent sequence. The
Vent button will turn yellow
when the chamber is vented.
Load Your Sample – 2
• It takes 30-45 seconds for
the chamber to vent.
• When the chamber is
vented, pull the handle bar
straight away from the
column to open.
• You will hear nitrogen still
being vented into the
chamber while you have it
open. (But if you keep the
chamber open for an
extended period it will valve
closed.)
Load Your Sample – 3
• Using the tweezers load
you sample onto the
stage.
• Make sure it is properly
seated.
(Remember to have
your samples ready.)
Load Your Sample – 4 - Height
• Use the tool provide for
height adjustment. This
makes sure that your
sample is under 10mm. If it
is then your sample will not
hit any detector when
loading.
Load Your Sample – 5
• Close the chamber
door. Hold with on
hand.
• Click “Pump” in the
Microscope Control.
Vac OK
• The chamber will
proceed through a
pump down procedure.
• In about 2 minutes the
“Vac OK” should appear
beneath the Pump
button. If it does not,
STOP, something is
wrong.
Turn on the electron Beam
• Click the kV button in
the Beam section of the
Settings Page
• The Beam button will
turn yellow, and you
may see an image.
No image
• Go to a low magnification.
• No image? Then,
• Check to see that there is a current reading
next to the kV button.
• If no reading, get help.
• If yes, then
• Adjust Brightness and Contrast, or click Image!
on the Menu bar.
• Still no image, get help.
I see something – Focus
• You focus the beam (i.e., change the current in
the objective lens) by holding the right mouse
button and moving the mouse side to side.
When you hold the right mouse button you
see the cursor change to a horizontal double
arrow.
Moving the stage
• The stage is not motorized.
• Stage Center
–
–
–
–
Approximate stage readings for the center of a stub:
X = 74
Y = 76
Take care when changing the Z height. Do not crash your
sample into the pole piece.
– Remember that for X-ray analysis the Working Distance
should be at 10.
Move the stage to your area of
interest
• Make sure you are at a low magnification for
initial moves.
• Move X,Y, and Rotation as necessary.
Getting a good image – 1
• Focus and stigmators
• Focus as best as possible as described above.
• The adjust the stigmators:
– Press and hold the shift key while holding down the left
mouse button. This will change the cursor from the
double arrow to a hand that moves a horizontal and
vertical line.
– Adjust the stigmators to best image.
– Then focus, then stigmators.
Getting a good image – 2
• Experimenting with Accelerating Voltage,
beam current (spot size), Working Distance,
coating of the sample, and other factors.
• You may have to work at obtaining what you
want. Remember there must be sufficient
intrinsic contrast.
• Secondary Electrons for most images, but
where you want to see chemical contrast,
backscattered electrons may be best.
Save and image
• Save your images to the “aaa-data” directory
on the d drive.
• See separate tutorial for transferring data
from the XL-control PC to the Dell.
Shutdown
•
•
•
•
•
•
Vent the chamber.
Remove your sample.
Pump the chamber down.
Put all tools away.
Pick up materials.
Sign out.
Troubleshooting
• Do not troubleshoot the instrument without
help.
• If a problem occurs, describe it in detail when
you log out of the FOM.