Silicon wafers

Which is closest to the mass of one silicon wafer 300 mm in diameter and 775 µm thick? (Silicon density is about 2.33 g/cm³.)

  1. AAbout 13 g
  2. BAbout 1,280 g
  3. CAbout 128 g
Show answer and explanation

Answer: C. About 128 g

The volume is π × (15 cm)² × 0.0775 cm ≈ 706.9 cm² × 0.0775 cm ≈ 54.8 cm³. Multiplying by the density of 2.33 g/cm³ gives about 128 g.

  • A. About 13 g is an order of magnitude too small.
  • B. About 1,280 g is an order of magnitude too large.
  • C. Correct. About 54.8 cm³ × 2.33 g/cm³ ≈ 128 g.
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More Silicon wafers questions

  1. Which method has been used to make multicrystalline silicon ingots for solar cells cheaply and in large volumes?
  2. When finishing a CZ pull, why is the ingot diameter gradually reduced (a tail cone is formed) before separating it from the melt?
  3. Which is closest to the typical concentration of interstitial oxygen in silicon crystals grown by the CZ method?
  4. In the mirror polishing (final CMP polishing) of silicon wafers, what is commonly used as the abrasive in the slurry?
  5. What is the main use of low-resistivity n⁺ silicon wafers heavily doped with arsenic or antimony?