A semiconductor has electron concentration of 5 × 1012 per cm3 and a hole concentration of 8 × 1013 per cm3. What can be concluded about the nature of the semiconductor?

A semiconductor has electron concentration of 5 × 1012 per cm3 and a hole concentration of 8 × 1013 per cm3. What can be concluded about the nature of the semiconductor? Correct Answer It is a p-type semiconductor

The correct answer is option 2) i.e. It is a p-type semiconductor

CONCEPT:

• Semiconductors: Semiconductors are materials that have conductivity between conductors and that of insulators.
  • The missing electrons (holes) are the positively charged particles whereas electrons are the negatively charged particles in a semiconductor. The electrons and holes have an equal magnitude of charge but opposite polarity.
• The conductivity of semiconductors is improved by adding suitable atoms called impurities and this process is called doping.
  1. ​A p-type semiconductor is a semiconductor doped with atoms with three valence electrons which forms a covalent bond with the semiconductor and leaves behind a hole.
  2. An n-type semiconductor is a semiconductor doped with atoms with five valence electrons which form four covalent bond with the semiconductor and leaves behind an extra electron.

EXPLANATION:

• An intrinsic semiconductor is a pure semiconductor without any dopant species present in it. So, it will have the same concentration of electrons and holes.
• Here, the concentration of holes is more than that of the electrons. 
• A p-type semiconductor has an extra hole for each dopant atom added to the pure semiconductor. So, a p-type semiconductor has more hole concentration.
• Thus, the given semiconductor is a p-type semiconductor.