MHT CET202618 April 2026Evening ShiftPhysicsSemiconductorsActual
For intrinsic semiconductor, if n_h and n_e represent the number of holes per unit volume and the number of free electrons per unit volume respectively then
Options
- An_h < n_e
- Bn_h > n_e
- Cn_h = n_e
- Dn_h n_e
Correct answer
C. n_h = n_e
Step-by-step solution
In an intrinsic semiconductor, charge carriers are generated by the thermal excitation of electrons from the valence band to the conduction band. Every time an electron is excited to the conduction band, it leaves behind exactly one hole in the valence band. Therefore, the number of free electrons per unit volume ( n_e ) is always equal to the number of holes per unit volume ( n_h ). Thus, n_h = n_e . Answer: n_h = n_e