GATE EC 2024 Set 1 — Question 63
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Electronic Devices → Semiconductor Physics → Fermi Level & Doping
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Question
A non-degenerate n-type semiconductor has 5 % neutral dopant atoms. Its Fermi level is located at 0.25 eV below the conduction band () and the donor energy level () has a degeneracy of 2. Assuming the thermal voltage to be 20 mV, the difference between and (in eV, rounded off to two decimal places) is _________.
Correct answer
0.17 to 0.19
Solution
The fraction of neutral donors is given by the occupancy probability of the donor level :Given:
- (5% neutral)
- (degeneracy)
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