INFICON STC-2000A Thin Film Deposition Controller Operating Manual - Manual (Page 25)

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STC-2000A DEPOSITION CONTROLLER
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Returning to STC-2000A specifics, some additional STC-2000A terminology definitions must now be
given.
Beyond sensor information and power supply control voltage, the STC-2000A also allows the user to
define the other parameters that are critical in the deposition process.
In STC-2000A terminology, a film is defined as a list of user programmable deposition related
parameters. Typically, one material deposition is accomplished per film (describes specific: material,
mechanical setup, timing, etc.). The STC-2000A can store up to 50 films (referred to as a film recipe
library). A process is a list of film implementations. Each film implementation is referred to as a layer (or
step in the process). Process layers can use the same film many times or use any combination of different
films.
The STC-2000A has 2 basic process control modes: sequencing mode and non-sequencing
mode. While in either one of these modes, manual mode (manual control of power) may be invoked. In
addition, a test mode can be employed to simulate (w/ simulated rate information) a crystal sensor input
while in any combination of the modes just described. Simply put, the sequencing / non-sequencing mode
difference is that of having or not having a process. Non-sequencing mode does not have a process (or at
least nothing named as such). Non-sequencing mode uses 1 implicit process which can run 1 film. The
non-sequencing mode is easiest to configure (user programs an active film). The sequencing mode is more
complicated only by the additional programming of a process[es] that calls out a film or films.
The STC-2000A retains the non-sequencing mode for historical compatibility and for simple
depositions.
On the subject of films and processes, that which is referred to as active is that which is queued to
be run when the start sequence is initiated. In other words, except for a co-deposition process, only one
film is being deposited at one time and one process (the active process) is calling out that one film in one of
its steps. When a process is run (start key sequence), it uses the single process that was selected as the
active process (on the Main Menu). Likewise, the film that was selected by the active process as the active
film will become the running film. [The non-sequencing mode has only one inherent unspecified process
and films are manually selected to be active. Only the film selected as active will be run (Main Menu in
non seq mode).] Regardless of mode selection, an active process or active film can be edited (modified)
while a process or film is running but only in a limited manner. This prevents potentially dangerous
situations from occurring. The limitations, that is, the parameters that are not changeable while a process
(or film ) is running include the following:
Film parameters: SS Map Select, Pocket Select, Etching Mode.
Map parameters: CH x Start Mode, Source full power, Source out channel, Indexer Sync Mode.
Min ~~~ XTALS [3 parameters] (evaluated at start only except for RE-VERIFY key usage).
Process: Film# of current running step, Process length (no step insertion/deletion).
A seeming inconsistency can apparently arise when in the non-sequencing mode as the STC-2000A can be
started using the MANUAL key from the idle state or the ready state. The apparent inconsistency would be
caused when a parameter, such as the SOURCE FULL POWER (SS MAP REVIEW), is changed and
started or restarted using the MANUAL key instead of the START key. The MANUAL key, although
legitimate to use, does not update [resync] parameters as they are reflected on the RUNTIME screen.
Likewise, starting [restarting] and stopping a using the MANUAL key will not incorporate changes made
unless the start key (or a system reset, or power on / off cycle) has been employed. Using the MANUAL
key alone continues with the initial parameter settings and does not utilize the changes, in any, that are
made. Otherwise, in other cases or in sequencing mode, an inhibited error message appears when parameter
updates are attempted during an unsafe period.
SECTION 2.XX page 25 of 292