Etching

Which research-stage etching method neutralizes plasma-generated ions before they hit the wafer, suppressing charging and UV damage?

  1. AChemical mechanical polishing
  2. BNeutral beam etching
  3. CWet etching
Show answer and explanation

Answer: B. Neutral beam etching

Neutral beam etching neutralizes plasma ions, for example by passing them through a grid, and directs the resulting directional neutral particles at the wafer. Having no charge, they cause no charging damage, and UV light from the plasma is also blocked, so the method is expected to suit damage-sensitive materials and ultra-fine structures.

  • A. Chemical mechanical polishing planarizes by polishing.
  • B. Correct. It processes with neutralized particles.
  • C. Wet etching uses solutions, not beams.
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More Etching questions

  1. Why are coatings such as yttrium oxide (Y2O3) used on the inner walls and parts of plasma etch tools?
  2. In plasma etch tools, what is the main role of the focus ring surrounding the wafer edge?
  3. Which correctly describes anisotropic etching?
  4. Which correctly describes 'selectivity' in etching?
  5. Which is a general characteristic of wet etching?