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An N-type semiconductor having uniform doping is biased as shown in the figure. If EC is the lowest energy level of the conduction band, EV is the highest energy level of the valance band and EF is the Fermi level, which one of the following represents the energy band diagram for the biased N-type semiconductor?

An N-type semiconductor having uniform doping is biased as shown in the figure. If EC is the lowest energy level of the conduction band, EV is the highest energy level of the valance band and EF is the Fermi level, which one of the following represents the energy band diagram for the biased N-type semiconductor? Correct Answer <img alt="F1 S.B Madhu 25.07.20 D 17" src="//storage.googleapis.com/tb-img/production/20/07/F1_S.B_Madhu_25.07.20_D%2017.png" style="width: 175px; height: 113px;">

Concept:

1) In an n-type semiconductor, the Fermi level is close to the conduction band and below it.

2) The slope in the band diagram represents the presence of the electric field, with the electric field pointing upward on the slope.

3) Electrons will flow from higher potential energy to lower potential energy, in the dissection opposite to the electric field.

4) If a positive voltage is applied at one end of semiconductor, then at this end, the energy level shifts down by an amount of qV or eV.

[ alt="F4 S.B Madhu 30.07.20 D14" src="//storage.googleapis.com/tb-img/production/20/07/F4_S.B_Madhu_30.07.20_D14.png" style="width: 370px; height: 100px;">

[ alt="F4 S.B Madhu 30.07.20 D15" src="//storage.googleapis.com/tb-img/production/20/07/F4_S.B_Madhu_30.07.20_D15.png" style="width: 410px; height: 138px;">

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