Cleanrooms and equipment

As circuits are scaled down, how does the size of particles that must be controlled in the cleanroom change?

  1. AIt becomes larger
  2. BIt becomes smaller
  3. CIt does not change
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Answer: B. It becomes smaller

Particles that are not negligible compared with pattern dimensions cause defects such as shorts and opens in wiring. As scaling shrinks line widths and spaces, even smaller particles become fatal defects, so the size of particles to be controlled shrinks and the required cleanliness becomes stricter.

  • A. Smaller particles become a problem as scaling advances.
  • B. Correct. Control must extend to smaller particles.
  • C. As dimensions shrink, the size of particles that matter changes too.
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More Cleanrooms and equipment questions

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  2. Which statement about ISO 14644-1 cleanliness classes is correct?
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