Updated 09/18/2023

Wafer cleaning issues at the wet process

Model of the failure:

The chemistry evaporates too fast, therefore particles remain on the

Short term solution:

Reduce the evaporation rate of the chemistry (water at rinsing)

  • Increase air pressure above the wafer
  • Reduce the temperature of the chemistry
  • Adjust the flow of the chemistry and rotation rate of the wafer to keep the chemistry on the wafer during the process. Keep in mind that the flow increases the amount of chemistry while wafer rotation removes the chemistry from the wafer

Long term solution

Use a shower (multiple nozzles system) instead of a single movable nozzle. The flow should be adjustable above different areas of the wafer.


Multy-nozzles system:

Adjust recipe for no "empty" areas on the wafer during the process

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