Question

In an unbiased p-n junction, holes diffuse from the p-region to n-region because

• A. Free electrons in the n-region attract them.
• B. They move across the junction by the potential difference.
• C. Hole concentration in p-region is more as compared to n-region.
• D. All of the above.

Answer 1

Answer: (C)

Hole concentration in p-region is more as compared to n-region.

The diffusion of charge carriers across a junction takes place from the region of higher concentration to the region of lower concentration. In this case, the p-region has greater concentration of holes than the n-region. Hence, in an unbiased p-n junction, holes diffuse from the p-region to the n-region.