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Tergeo plasma cleaner operator’s manual
Revision: B3, Year 2020
Figure 3, downstream/remote plasma cleaning mode
6.4 Pulsed operation mode
If the pulsed operation option is purchased, the duty ratio of the rf power supply can be changed.
Full duty ratio is 255 (e.g. continuous operation). Duty ratio can vary from 2 to 255. Pulse
frequency is 480Hz. Low duty ratio pulsed mode can further reduce the average plasma power and
change discharge chemistry. If pressure is too high or rf power is too low, plasma may fail to ignite
in pulsed operation mode. If plasma fails to ignite, please increase rf power and reduce the pressure
to around 30~150mTorr for immersion mode and 75~100mTorr for remote mode.
Figure 4,
pulsed operation mode.
If the pressure in the downstream sample chamber is too low,
plasma from the remote plasma source may diffuse into the sample
chamber. Then user should increase the gas flow rate/pressure so
that remote plasma will die out sooner.