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Tergeo plasma cleaner operator’s manual
Revision: B3, Year 2020
Chapter 9
System settings
System settings can be modified in the settings screen. Click the system button in the bottom right
corner of the main screen to enter the system screen.
“Ignite plasma
before
or
after
flowing gas”
. The system can either ignite the plasma before flowing any
process gas or until the chamber pressure is stabilized after the process gas flow rate is set to the recipe
setting. It’s usually easier to ignite the plasma when the chamber pressure is lower (no process gas flow).
Different choice may impact the initial plasma intensity during the plasma ignition. Ignite the plasma
before flowing the gas usually has longer plasma stabilization period.
“Upper limit pressure before cleaning starts”
specifies the maximum background pressure allowed for
plasma cleaning to start during a recipe execution session. If there is a vacuum leak or the vacuum pump
is not working properly, the system may not be able to reach a pressure lower enough for plasma
cleaner to function correctly. The user can modify this number if necessary. If the user wants to make
sure the chamber is evacuated thoroughly before the plasma cleaning starts, this value can be reduced.
But it has to be higher than the “lower limit pressure before cleaning starts”.
“Lower limit pressure before cleaning starts”
: When the background pressure in the sample chamber
drops below this pressure, the system will start rf power immediately even if the background pressure
can be further reduced. If background pressure stabilizes to a value above the
“Lower limit pressure
Figure 15, system setting screen
