Metrology and analysis

Compared with bright-field wafer inspection, which images patterns directly, what characterizes dark-field inspection, which captures only scattered light?

  1. AIt detects scattered light from particles and the like with high sensitivity and readily inspects large areas at high speed
  2. BIt always has higher resolution than bright field
  3. CIt cannot detect particles
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Answer: A. It detects scattered light from particles and the like with high sensitivity and readily inspects large areas at high speed

Dark-field inspection rejects specularly reflected light and captures only light scattered by particles and defects, so small particles appear bright against a dark background and inspection is fast. Bright-field inspection images patterns directly with reflected light and excels at finding pattern-shape defects. The two are used according to purpose.

  • A. Correct. Scattered light enables sensitive, fast particle detection.
  • B. For pattern-shape defects, bright field can be superior.
  • C. Dark field is well suited to detecting particles.
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