Cleanrooms and equipment

What is the main purpose of replacing (purging) the inside of a FOUP with nitrogen?

  1. ATo suppress oxidation of wafer surfaces and adhesion of moisture and molecular contamination
  2. BTo make the FOUP heavier
  3. CTo cool the wafers
Show answer and explanation

Answer: A. To suppress oxidation of wafer surfaces and adhesion of moisture and molecular contamination

With air inside a FOUP, wafer surfaces may oxidize or pick up moisture and molecular contamination during waiting time between steps. Purging with nitrogen reduces oxygen and moisture and preserves surface condition, which has become important in advanced processes.

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