Question

When a p-n junction diode is forward biased:

• A. the barrier height and the depletion layer width both increase.
• B. the barrier height increases and the depletion layer width decreases.
• C. the barrier height and the depletion layer width both decrease.
• D. the barrier height decreases and the depletion layer width increases.

Hint:

Forward biasing a diode reduces the barrier to charge flow, enabling current to pass through the junction, which is the basis of diode operation in electronic circuits.

Answer 1

The Correct Option is C

Outcome: Forward biasing a p-n junction diode lowers the potential barrier. This process has the following consequences:

1. Barrier Height: Forward bias reduces the internal electric field in the depletion region, thereby lowering the barrier height. This facilitates easier movement of electrons and holes across the junction, leading to higher current. Consequently, the barrier height is diminished.
2. Depletion Layer Width: Forward bias also decreases the width of the depletion region. The external voltage imparts energy that weakens the resistance to carrier movement. This results in increased carrier injection and a weakened electric field, leading to a reduction in the depletion layer's width.

In summary, forward biasing a p-n junction diode causes both the barrier height and the depletion layer width to reduce.