Question

Dark current in a photo-diode depends on the

• A. concentration of majority carriers.
• B. concentration of minority carriers.
• C. applied voltage.
• D. frequency of the incident light.

Hint:

Dark current is the reverse saturation current of the photodiode, which is carried by thermally generated minority carriers.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept
A photodiode works in reverse bias. The small current that flows with no light falling on it is called the dark current.

Step 2: Origin of the current
It is the reverse saturation current. It is carried by minority carriers that are generated thermally and swept across the junction.

Step 3: Conclusion
So the dark current depends on the concentration of minority carriers.

Final Answer:
Dark current depends on the concentration of minority carriers. \[ \boxed{\text{(B) }\text{concentration of minority carriers}} \]