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Operating Procedures: Patterning
Serial Patterning
All patterns defined on the screen are processed consecutively; 
milling / deposition is completed on one pattern before moving to the
next one. Serial patterning is always used with cleaning cross section
milling. This is the default patterning mode.
Parallel Patterning
All patterns defined on the screen are processed concurrently, 
one pass of the beam is completed on all patterns before moving to the
second pass. Parallel patterning is typically used with regular cross section
milling and to avoid a redeposition of material on the adjacent areas.
With parallel patterning, the mill time is recalculated to include all the
patterns that are displayed in the image window.
When an user changes to the Parallel mode, the following pattern
properties in the group must necessarily be the same: Number of
Passes, Beam, and Gas properties. The first selected pattern determines
these values for all other ones.
Other properties (Application File, Overlap, Sputter Rate, Recovery Time
and Depth) are also all set to those of the first selected pattern to avoid
confusion, even though they could theoretically remain unchanged.
Restoring Serial mode does not undo these changes; the properties
remain as in the Parallel mode.
Patterns Processing
Select the pattern from the Pattern type selector drop down list. Once
selected, the cursor is ready to draw a suitable pattern onscreen (quad or
single screen).
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Importing / Exporting Patterns
Defined patterns may be imported via the File / Import / Patterns… menu
item or exported (saved) via menu File / Export / Patterns… menu item
(see Chapter 3).
The saved file (.ptf) contains all parameters found at the Patterning
property editor (Basic / Advanced - see below) for all patterns drawn in
the selected quad. It could be assigned to one of six (A - F) toolbar
Pattern Preset buttons (available only if activated via the Preferences…
/ General tab) by right-clicking above the selected button (becomes
yellow):
The Apply starts the patterning with the preset parameters 
(the same as clicking the button directly).
The Edit… opens the Pattern File (.ptf) selection process.
The set of toolbar Pattern Preset buttons could be saved / loaded by the
File / Export / Import / System Parameters… menu (see Chapter 3).
•
Pattern Editing
Once a pattern shape has been drawn, it can be modified.
Selected Pattern is denoted by the addition of resizing handles to the
pattern outline (pointer cursor).
Move / Rotate Pattern: press the cursor inside the boundary of the
pattern / in the vicinity of a corner and drag it (move / rotate cursor).
Holding the Ctrl + Alt keys while hitting any arrow key moves a pattern in
a respective direction for a fixed distance (one screen pixel).
Resize Patterns: press and drag the resizing handle until the desired size
is reached (horizontal / vertical / diagonal resizing cursor). Pressing the
Ctrl key while dragging forces dimensions to be changed proportionally.
Precise dimensions could be also entered in the Property editor.
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