For a forward biased p-n junction diode, which one of the following energy-band diagrams is correct? (\( \epsilon_F \) is the Fermi energy)
For a forward biased p-n junction diode, which one of the following energy-band diagrams is correct? (\( \epsilon_F \) is the Fermi energy)
Show Hint
- A
- B
- C
- D
The Correct Option is A
Solution and Explanation
In a forward biased p-n junction diode, the p-type side is connected to the positive terminal and the n-type side is connected to the negative terminal. This reduces the potential barrier, allowing current to flow. The Fermi level (\( \epsilon_F \)) moves closer to the conduction band in the n-type material and closer to the valence band in the p-type material.
Step 2: Identifying the correct diagram.
Option (A) shows the energy bands with the correct behavior for a forward biased p-n junction. The Fermi energy levels are shifted as expected in forward bias, and the conduction and valence bands are aligned correctly.
Step 3: Conclusion.
Thus, the correct energy-band diagram for a forward biased p-n junction diode is shown in option (A).
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