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Asked in GSEB Board March 2016 · Doping and carrier concentration
Idea: in p-type material the dopant is trivalent, so each dopant atom leaves one covalent bond an electron short. That missing electron is a hole.
Those doping holes far outnumber the electron-hole pairs that thermal energy alone creates, so holes are the majority carriers and electrons the minority carriers.
The two densities are tied together by nₑ nₕ=nᵢ², so raising nₕ by doping pushes nₑ down by the same factor -- the imbalance is large, not marginal.
So in a p-type semiconductor nₑ < nₕ.
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