Zener Diodes

Step 1: Understanding the relationship.
In a Zener diode, the breakdown voltage is inversely proportional to the width of the depletion region. The breakdown voltage can be related to the width of the depletion region by the equation: Where: - and - (new width)
Step 2: Apply the relation.
Substitute the known values into the equation to solve for :
Step 3: Conclusion.
The Zener diode will have a breakdown voltage of 5V when the depletion region width is reduced to 1 mm. Therefore, the correct answer is (2) 5V.