Silicon wafers

Which is one reason SiC wafers are difficult and expensive to manufacture?

  1. ABecause crystals can be grown very quickly by the CZ method
  2. BBecause the raw material is more abundant than silicon
  3. CBecause SiC does not melt at normal pressure, crystals must be grown at high temperature by methods such as sublimation, so growth is slow and defects form easily
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Answer: C. Because SiC does not melt at normal pressure, crystals must be grown at high temperature by methods such as sublimation, so growth is slow and defects form easily

SiC sublimes rather than melting at normal pressure, so crystals cannot be pulled from a melt as with silicon. They are grown by sublimation methods, in which the source sublimes at temperatures above 2000 °C and recrystallizes on a seed, so growth is slow and defects such as dislocations form easily.

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More Silicon wafers questions

  1. Roughly what size in inches is a silicon wafer 300 mm in diameter commonly called?
  2. What is the cylindrical block of single-crystal silicon grown by the CZ method or similar, before it is cut into wafers, called?
  3. What is the main reason silicon wafers are round?
  4. Which pair of Japanese companies holds a large share of the global silicon wafer market?
  5. In the CZ method, what is the purpose of growing a thin neck just after the seed crystal at the start of pulling (necking)?