Concept:Trivalent impurity atoms have 3 valence electrons, leaving one covalent bond deficient of an electron when substituting a tetravalent host atom in the lattice.
Formula:Qualitative concept / No formula required.
Solution:- The vacancy created in the fourth covalent bond acts as an electron acceptor site, known as a hole.
- Because holes behave as effective positive charge carriers, the resulting material is a P-type extrinsic semiconductor.
Why other options are incorrect:- Option A: N-type semiconductors are produced by doping with pentavalent impurities (e.g., Phosphorus, Arsenic, Antimony).
- Option B: Pure, undoped semiconductors are intrinsic.
- Option C: Doping increases semiconductor carrier density; it does not create a superconductor.
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