Conditioning |
Gas
compostion depends not
only from the MFC's, they depends from the chamber wall status
(deposition) too. The plasma parameters are enabled to mirror the gas
composition. The tool parameters not!
|
First Wafer Effect |
The first wafer effect mostly
caused by
increased gas temperatuer (decreased gas density). The plasma
parameters are enabled to mirror the gas density. The tool parameters
(pressure) not! Optimization of warm up is possible.
|
FDC |
The
plasma parameters represent the real tool (plasma) which treat the work pice (wafer). The recipe and
hardware are only the presettings of the tool plasma.
The electron collsion rate is most sensitive to variation of chemistry (gas compostion), the plasma density indicates physical variations (hardeware: generator, match box, spare parts, reworked tool kids) more efficient. |
Pre-process Issues |
For example:
|
Chamber Matching |
The
plasma parameters
represent the real tool (plasma). Differences in the plasma process are
detectable by the plasma parameters.
|
Process Development |
Only
the plasma parameters can give information about the sensitivity of the
plasma compared to the tool parameters.
|