Examkin

Question

Difficulty: MediumDiodes

In a semiconductor PN junction diode, applying an external reverse-bias voltage causes the depletion region at the junction to widen, which prevents the conduction of majority charge carriers.

Answer: Answer

Answer

True
Applying reverse bias attracts majority carriers away from the PN interface, widening the non-conductive depletion zone and preventing current conduction through the component.

Step-by-Step Solution

1
Identify the polarity of the applied external voltage across the diode terminals in reverse bias.
The positive terminal of the power source connects to the n-type cathode, and the negative terminal connects to the p-type anode.
Establishing the reverse-bias electrical configuration determines the direction of the electrostatic forces acting on internal charge carriers.
2
Determine how internal majority carriers respond to the applied electrostatic field.
Holes in the p-type region are pulled toward the negative terminal, and electrons in the n-type region are pulled toward the positive terminal.
Opposite electrical charges attract, pulling majority carriers away from the central PN boundary.
3
Evaluate the effect of charge carrier movement on the depletion layer and overall current flow.
The removal of mobile carriers from the junction widens the depletion layer of uncovered ionized atoms, preventing majority carrier flow and allowing only negligible minority leakage current.
The widened depletion layer acts as a high-resistance barrier to electric current, confirming the statement as true.

Key Concept

PN Junction Biasing and Depletion Layer Dynamics
Estimated Time:45s
Rate this question

Topics

Diodes

More questions from this topic