Process materials (gases and chemicals)

Which device in deposition and etch tools precisely measures gas flow and controls it to stay constant?

  1. AMass flow controller (MFC)
  2. BA pressure gauge alone
  3. CThe gas cylinder valve
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Answer: A. Mass flow controller (MFC)

A mass flow controller measures the mass flow rate of a gas with a thermal or similar sensor and adjusts a built-in valve to hold the set flow. Because gas flow strongly affects process results, each gas line has an MFC.

  • A. Correct. It measures and controls flow.
  • B. A pressure gauge only measures pressure and does not control flow.
  • C. A cylinder valve alone cannot control flow precisely.
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