Process materials (gases and chemicals)

What is the main reason extremely high purity is required of the gases and chemicals used in semiconductor manufacturing?

  1. ATo remove odors
  2. BBecause even trace impurities such as metals and particles degrade device characteristics and yield
  3. CTo raise prices
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Answer: B. Because even trace impurities such as metals and particles degrade device characteristics and yield

Trace metals in gases and chemicals that enter silicon increase leakage current and lower carrier lifetime, and particles become pattern defects. High-purity materials with impurities controlled at the ppb or ppt level are therefore used.

  • A. Removing odors is not the purpose.
  • B. Correct. Even trace impurities degrade characteristics and yield.
  • C. Raising prices is not the purpose.
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More Process materials (gases and chemicals) questions

  1. Which combination of material and surface treatment is commonly used for high-purity gas piping?
  2. Which device in deposition and etch tools precisely measures gas flow and controls it to stay constant?
  3. What is the main composition of positive resists widely used for g-line and i-line exposure?
  4. Which material is widely used for piping and containers of highly corrosive chemicals such as hydrofluoric acid?
  5. What is the typical method for producing, near the fab, the large volumes of nitrogen gas used in semiconductor plants?