Oxford Instruments Cypher SPM, Руководство пользователя

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Cypher SPM
User Guide
Wait for tip to reach sample:
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For the next minute or so Cypher will systematically move the tip closer to the sample until the
set point is reached.
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You can cancel the approach at any time by pressing AND HOLDING the Esc key on your com-
puter keyboard.
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When the process is complete, the computer will beep and the tip will be left about half the Z
range (about 3 microns) off the sample surface.
4. Q What's going on during the tip approach?
5. A Cypher executes a series of repeated steps. First the scanner fully extends the sample
toward the tip while monitoring the cantilever amplitude. If the amplitude reaches the set
point, the process stops. If not, the sample is fully retracted again and motors move the can-
tilever down by one extension length. The process is repeated until the sample is close enough
to the vibrating cantilever to reduce its amplitude to the set point. One final time the sample is
fully retracted and the cantilever is motored down just enough so that when the sample is
brought back up it will trip the tip amplitude set point at half the scanner's vertical extension
range.
3.
Meter check:
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Locate the Sum and Deflection Panel(Ctrl + 6).
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The values should be similar to the figure on the right, typical for a cantilever a few microns off
the sample surface.
4.
Engage:
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Hit the engage button on the Sum and Deflection meter panel.
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The scanner will extend the sample into contact with the tip and the Sum and Deflection panel will
look like the figure to the right.
Congratulations
The tip is on the sample surface.
5.
Question
How do I know my tip is firmly engaged on the sample surface?
Answer
Type in a slightly lower the set point (such as 650mV). If the Z voltage in the Sum and Deflection
meter panel does not change noticeably (i.e. more than a Volt) the tip is firmly on the surface.
Page 178 of 243 24 Engaging the cantilever on the sample