Controllers
Several hardware controllers are used with Agilent SPM systems.
The AFM Controller provides the high voltage and to the piezoes and other
control functions. Model 2500 is standard; Model 3000 provides optional
closed-loop scanning control.
The MAC Mode controller provides the drive signal for AC Mode
measurements (AAC only, or AAC plus MAC Mode).
The MAC III Controller includes three Lock-In amplifier to provide three
precise signals for AC Mode and other advanced operations. It enables
several unique imaging modes, including FMM, EFM and KFM Mode, and
provides other advanced Q Control for imaging with very low force and high
phase sensitivity.
CameraView
CameraView software enables PicoView to interface with the USB cameras
on Agilent's SPM systems.
To open the CameraView window choose Controls > Camera View. The
output from the SPM's camera will be displayed (in black and white for the
5400 SPM, otherwise in color).
You can set the Input type (default is Composite) and Resolution of the
displayed video (default is 320 x 240) at the bottom of the window.
Click the Snap! button to place the current contents of the window on the
clipboard to copy into another program.
Tool Bar
When PicoView starts up, the Main Window opens. This is the window from
which all other PicoView windows and dialog boxes can be accessed. The
header of this window contains a Menu bar with links to PicoView's controls,
and a Toolbar which lets you access the most frequently needed functions.
The toolbar buttons will change depending upon the Imaging Mode.
The Laser Alignment button (left) opens the
Oscilloscope/Laser Alignment dialog box. When the system
is in STM Mode the button is replaced by the Oscilloscope
button (right), which opens the Oscilloscope dialog box.
This button opens the Spectroscopy dialog box and
Realtime Plots window.
This button opens the AC Mode Tune dialog box and AC
Mode plot window . The button is only available when the
system is in ACAFM Mode.
The Imaging button opens the Realtime Images, Scan and
Motor and Servo dialog boxes.
The Approach button initiates the Approach sequence in
which the probe and sample are brought together.
The Withdraw button initiates the Withdraw sequence in
which the probe and sample are moved apart.
Approach
Clicking the Approach button in
the Toolbar starts the approach
process.
When you click the Approach
button, the stepper motor(s) raise
the sample stage toward the
cantilever by one step. The size
of the step is controlled by the
Step Size setting in the
Microscope Setup dialog box.
The Z piezo then moves the
probe toward the sample. The
distance the probe travels is
detemined by the Approach
Range setting in the Microscope
Setup dialog box. The Approach
Range should be at least twice Microscope Setup Dialog Box.
the Step Size to prevent the tip
from crashing into the sample.
In AFM Mode the controller
monitors the deflection of the
cantilever, looking for a deflection
value greater than or equal to the
Stop At value (set in the Scan
and Motor dialog box). If the
deflection voltage is less than the
Stop At value, or if no deflection
voltage is detected, the sample
stage will be raised another step
and the process will repeat.
When the Stop At value is
reached, the Approach stops and
the servo becomes active. The
servo is governed by a feedback
loop that adjusts the Z piezo to
maintain a constant deflection at
the cantilever, to maintain the
Setpoint value (set in the Servo
dialog box).
In STM Mode, the Approach
process is similar, except that the
Stop At and Setpoint values are
currents rather than deflection
voltages.
The Direct setting in the Scan and
Motor dialog box controls how the
approach process wll take place.
When this box is checked,
Approach is completed with the
Servo on, stopping when the
servo pulls back, the Stop At
value is reached, or the tip has
moved the Approach Range
distance without engaging the
surface.
When this box is not checked, the
system uses an Incremental
Approach. Again, the Z piezo
moves the tip toward the surface
using the Stop At value is
reached, or the tip has moved the
Approach Range
distance. However, if the surface
is not found, the tip is withdrawn,
the stepper motor moves one
step, and the process is repeated.
Incremental approach should be
used unless false engages make
it impossible (such as when using
a soft cantilever in liquid).
Withdraw
The Withdraw sequence moves the tip away from the sample so that it can
be moved safely to another area of the sample or removed. The size of the
step is controlled by the Step SIze setting in the Microscope Setup dialog box.
To initiate a withdraw, click the Withdraw button on the Toolbar. The
sample and tip will be moved apart a distance specified in the Scan and
Motor dialog box. Withdraw is always completed at full speed.
Smart Index Controls
Most editable text boxes in PicoView Shft + increments by
let you use "Smart Index Controls" to ↑↓ 1.000 or 1000
adjust a parameter's value using the
keyboard. increments by
↑↓
0.100 or 100
To use the feature, click inside the box
Ctrl + increments by
for the value you want to adjust. Then,
↑↓ 0.010 or 10
use the Up ↑ and Down ↓ arrow keys,
in conjunction with the Ctrl and Shift Shft +
increments
keys, to incrementally adjust the value. Ctrl +
by 0.001 or 1
↑↓
The orders of magnitude adjusted by
each key combination is shown at the Use the Up and Down arrow keys
right. For example, holding Shift and inconjunction with the Shift and Ctrl
pressing ↓ would change 1.111 to keys to adjust parameters over four
0.111. Holding Ctrl and pressing ↑ orders of
would change 1.111 to 1.121.The
actual increments will vary from control
to control.
The scroll wheel and arrow keys can
also be used to change values.
Holdold down Shift while using the
scroll wwheel or arrow keys to change
by larger steps, or hold Ctrl while
scrolling to change in smaller steps.
Holding Shift and Ctrl together while
scrolling will change by a smaller step
yet.
You can always input a numerical
value directly into the box.