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Tergeo plasma cleaner operator’s manual
Revision: B3, Year 2020
when the impurity is pumped away. For argon plasma, the intensity will usually gradually increase. If the
system is used to ash a thick layer of polymers, the gas composition may also changes significantly
during the course of the etching.
If anodized aluminum is placed inside the sample chamber as the sample holder, it will usually outgas a
lot because the surface of the anodized aluminum is very porous. It can significantly change the gas
composition. Please avoid anodized sample holder or other parts that will outgas a lot if high purity
plasma is required.
If the plastic or Teflon tubing is used to connect the gas port between the plasma cleaner and the
compressed gas bottle, there is always slow gas leakage through the plastic and Teflon tubing; room air
will gradually leak into the plastic or Teflon tubing. If the plasma cleaner has been idle for a long time,
the purity of the gas inside the plastic or Teflon tubing will reduce. For oxygen gas, the plasma will
become brighter and more purple instead of pure white, and the plasma intensity reading may increase
for pure oxygen plasma. To prevent the contamination of the gas, keep the compressed gas bottles close
to the plasma cleaner to shorten the length of the plastic or Teflon tubing, if necessary, use ¼ inch
copper, aluminum or stainless steel tubing instead of plastic or Teflon tubing. For most of the plasma
cleaning applications, such contamination of the process gas doesn’t have a serious effect. If high purity
argon or hydrogen gas is required to reduce the oxidation of the samples, such as silver or copper
samples, then it is recommended to pump out of the contaminated gas in the gas tubing before
processing such samples. Click the pumping down button on the LCD touch screen to pumping down the
plasma cleaner, then set the gas flow rate to 99 sccm on the MFC. Keep it for 5~10 minutes to pump out
the contaminated gases. Depending on the pressure in the tubing, the actual flow rate may be lower
than 99sccm even if the set flow rate is 99sccm.
10.13 If the plasma is too weak to be detected by the plasma sensor (value
is below 2), how to let the timer start counting down and run a recipe?
There are two trigger options for the timer. The default trigger is plasma sensor. The timer will start
counting down when the system detects the plasma is ignited. The second trigger option is rf power
supply. In this mode, the timer will start counting down once the system detects the rf power is ON.
10.14 Clean and replace the front cap o-ring
Both Viton and silicone o-ring can be used on the front cap groove. The oxygen plasma may etch Viton
o-ring slowly and turns the surface white. Please wipe and clean the Viton o-ring surface if necessary.
Silicone o-ring is more resistant to oxygen plasma. But the gas leak rate is slightly higher. Teflon
encapsulated Viton and silicone o-ring is the ideal choice. If the o-ring needs to be replaced, please
purchase size 350 (Standard Inch AS568) o-ring for Tergeo and Tergeo-EM plasma cleaner. The size of
the o-ring for Tergeo-plus is 363 (Standard Inch AS568). Please refer to section 10.1 for clean and grease
the o-ring groove with Apiezon 501 PFPE vacuum grease.
