Question

For an n-type silicon, an extrinsic semiconductor, the natural logarithm of normalized conductivity (σ) is plotted as a function of inverse temperature. Temperature interval-I corresponds to the intrinsic regime, interval-II corresponds to saturation regime and interval-III corresponds to the freeze-out regime, respectively. Then

• A. the magnitude of the slope of the curve in the temperature interval-I is proportional to the bandgap, Eg
• B. the magnitude of the slope of the curve in the temperature interval-III is proportional to the ionization energy of the donor, Ed
• C. in the temperature interval-II, the carrier density in the conduction band is equal to the density of donors
• D. in the temperature interval-III, all the donor levels are ionized

Answer 1

Answer: (A), (B), (C)

the magnitude of the slope of the curve in the temperature interval-I is proportional to the bandgap, Eg

Answer 2

The correct option is (A): the magnitude of the slope of the curve in the temperature interval-I is proportional to the bandgap, Eg, (B): the magnitude of the slope of the curve in the temperature interval-III is proportional to the ionization energy of the donor, Ed and (C): in the temperature interval-II, the carrier density in the conduction band is equal to the density of donors