What is the primary source of charge carriers in an intrinsic semiconductor at room temperature?
**Types of semiconductors** elemental Si, Ge group IV with 4 valence electrons, compound GaAs, InP etc. Intrinsic has n_e = n_h, extrinsic doped with pentavalent donors (P, As) gives n-type excess electrons, trivalent acceptors (B, Al) gives p-type excess holes, resistivity range semiconductors 10⁻⁵ to 10⁶ Ω·m vs insulators 10¹¹ Ω·m. In an intrinsic semiconductor, charge carriers (electrons and holes) are generated by thermal excitation at temperatures above 0 K, breaking covalent bonds and creating electron-hole pairs. Substituting values gives Thermal excitation, which matches expected behav
Ref: NCERT > Physics Book > Electronic Devices > Semiconductors, Types and Energy Bands