Plasma processes

Plasma processes are amongst the most aggressive for elastomer seals, particularly those in critical locations that are exposed to the chemistry and in proximity to the wafer or substrate. The most aggressive plasma processes for seals include oxygen resist strip and radical based plasmas such as remote NF₃ etching and chamber cleans using remote plasma sources (RPS).

All seals, particularly those in critical locations, will degrade over a period of time. No single seal material is optimized for all chemistries or applicable to every tool location and product type. Appropriate choice of PPE recommended products will lead to:-

• Cost optimized recommendation dependent on application
• Low erosion rates
• Low trace metal levels where critical
• Low particle release rates where critical
• Minimized impact on device yield and electrical yield
• Reduced cost of consumables (CoC)

The table below indicates recommended and compatible elastomer material grades. Primary grades are geared towards critical system / tool locations.

Extensive plasma resistance testing was carried out on 20+ elastomer materials available on the market, including those from the leading suppliers.  Find out how each material performed in terms of erosion rates in four basic plasma chemistries relative to equivalent PPE grades.

For further guidance on appropriate seal choices please find your nearest sales contact. You can also see our Perlast^® materials for semiconductor applications here.