Select the CORRECT statement(s) regarding semiconductor devices.

Electrons and holes are of equal density in an intrinsic semiconductor at equilibrium.
Collector region is generally more heavily doped than Base region in a BJT.
Total current is spatially constant in a two terminal electronic device in dark under steady state condition.
Mobility of electrons always increases with temperature in Silicon beyond 300 K.

Correct answer: Electrons and holes are of equal density in an intrinsic semiconductor at equilibrium.

Solution

In an intrinsic semiconductor, the number of electrons generated in the conduction band is equal to the number of holes created in the valence band, resulting in equal density of both charge carriers at thermal equilibrium.

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