INFICON STC-2000A Thin Film Deposition Controller Operating Manual - Manual (Page 85)

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STC-2000A DEPOSITION CONTROLLER
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This parameter indicates the minimum number of crystals in the starting group when a process is
begun. To reiterate, this is a START value. The intent is to provide a qualification minimum for run
acceptability. If more than 1, averaging is assumed in conjunction with Channel x Start Mode map
parameter programming to more than 1 active sensor. This is a parameter with global scope.
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Parameter
MINIMUM BACKUP XTALS
Minimum Number of Backup Crystal Channels: 0 - 1
Units Channels
Selecting the minimum number crystal channels for possible use as backup crystals
This parameter indicates the minimum number of crystals to be used as backup crystals. This is a
parameter with global scope.
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Parameter
MINIMUM ACTIVE XTALS
Minimum Number of Active Crystal Channels: 1 - 2
Units Channels
Selecting the minimum number crystal channels that are active
This parameter indicates the minimum number of crystals that will be active when a process is
started. The intent is to provide a guard for the minimum constellation of averaging crystal sensors the user
decides are necessary. For a process to run, this value cannot be greater than that of the minimum start xtals
map parameter value. This is a parameter with global scope.
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Parameter
CHANNEL DROP FILTER
Channel Drop Filter Mask Status: none / balance
Units None
Channel Drop Filter
This parameter enables/disables a filter mask for use during multi-sensor averaging. Each crystal
sensor has a unique map parameter group. Programming 2 crystal sensor channels as active automatically
invokes an averaging mode. Lost channels during averaging are handled by this Channel Drop Filter Mask
parameter when enabled. An example of a crystal sensor/channel loss is crystal life failure. This parameter
in the BALANCE setting, provides bumpless rate info if, for example, 2 channels are averaged and one
channel fails and has no assigned backup crystal sensor/channel for the failing channel. This is done by
keeping an historical buffer of the rate info stream for each of the 2 channels in this example case. When a
channel fails (without backup), the historical rate info from each of the 2 channels is used to produce a
composite multiplier based on the 2 channels when they were both working that will be used to fill in for
the missing channel's contribution. This is, of course, a simplification for the purposes of discussion. When
averaging, the preferred setting should be BALANCE. The setting of NONE allows the composite rate to
jump when a channel is lost (without a backup). The unit can also be set to fail when either of the 2 crystals
fails. This parameter has no effect unless in averaging mode. This is a parameter with global scope.
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Parameter
INDEXER SYNCHRONIZATION MODE
Indexer Synchronization: NONE, DELAY, FEEDBACK
Units None
Indexer Synchronization Mode
This parameter is used to provide pocket information in conjunction with the Film parameters:
Pocket Select and SS MAP SELECT. If indexer sync mode is set for either delay or feedback, then
following an XTAL verify, the indexer activity will commence before arriving at the RISE1 phase. Either a
1 of N or a binary (3 digit) value issued through output relays by I/O programming will select the correct
pocket. If indexer sync mode is set to none, then the POCKET SELECT parameter has no effect. This is a
parameter with global scope.
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Parameter
INDEXER SYNCHRONIZATION TIME
Indexer Synchronization Time: 2 – 999 seconds
Units Seconds:
Indexer Synchronization Time
SECTION 3.XX page 85 of 292