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Tergeo plasma cleaner operator’s manual
Revision: B3, Year 2020
10.3 Plasma fails to ignite.
1.
If the plasma cleaner has been idle for a couple of hours, it might be hard to ignite remote
plasma source, especially at low pulse duty ratio. The user can run a high power
direct/immersion mode recipe for 1 minutes to warm up the system before carrying out low
power plasma cleaning. Once the system has been successfully ignited at high power. It will be
much easier to ignite the low power remote cleaning recipe within the next one hour.
2.
If auto tuner feature is purchased, make sure the auto tuner feature is enabled in the settings
screen. Then click the auto tune button in the main screen. Auto tuner can automatically
change to optimal ignition pressure and increase rf power for ignition. Once the plasma is
ignited, auto tuner will change to original gas flow and rf power setting. It’s usually easier to
ignite the plasma when the auto tuner position is close to the maximum. User can manually set
the auto tuner position to the maximum position (usually around 10,000) in the “System” screen.
But plasma intensity is usually relative lower at this impedance matching position.
3.
Increase the rf power or pulse duty ratio. Plasma may fail to ignite if the rf power or pulse duty
ratio is too low.
4.
For immersion plasma source, it’s always easier to ignite the plasma at a lower pressure
between 15~50mTorr. Shut off all the gas input and wait until the background pressure reaches
below 50mTorr. Start the rf power at low chamber pressure. Once the plasma ignites at low
pressure, set the rf power to desired value. Manually set auto tuner motor position to the
maximum value in the settings screen if necessary.
5.
For remote plasma source, the optimal pressure to ignite the plasma is around 75mTorr to
100mTorr. Increase the rf power to ignite plasma, then reduce the rf power immediately.
6.
If rf power is in pulsed mode, increase duty ratio to 255, e.g. CW mode.
10.4 Auto impedance tuning fails
1.
Calibrate autotuner travel limit in the settings screen.
2.
Use long range autotuner routine.
3.
If autotuner still doesn’t work properly after step 1 and 2. User can choose to run the system in
fixed matching condition.
a.
Manually set the auto tuner motor position to a value corresponding to the maximum
travel limit minus 2000.
b.
Disable the auto tuner. This will place the system into a fixed impedance matching state.
