Semiconductor physics

Which statement is correct when phosphorus (P) is added to silicon as an impurity?

  1. AIt becomes a p-type semiconductor with holes as majority carriers
  2. BIt becomes an n-type semiconductor with electrons as majority carriers
  3. CCarriers do not increase, and it remains an intrinsic semiconductor
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Answer: B. It becomes an n-type semiconductor with electrons as majority carriers

Phosphorus is a group V element with five valence electrons. When it enters the silicon (group IV) crystal, one electron is left over and becomes a conduction electron. Such an impurity is called a donor and produces an n-type semiconductor. To make p-type silicon, a group III element (acceptor) such as boron (B) is added.

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More Semiconductor physics questions

  1. What happens to the intrinsic carrier density when the temperature of an intrinsic semiconductor is raised?
  2. Which correctly compares electron and hole mobility in silicon?
  3. Where is the Fermi level located in an n-type semiconductor?
  4. Which correctly describes how the resistivity of an intrinsic semiconductor depends on temperature?
  5. In a semiconductor in thermal equilibrium, what is the product of electron density n and hole density p (n×p)? (ni: intrinsic carrier density)