Question

A region of negative differential resistance is observed in the current voltage characteristics of a silicon PN junction if
1. Both the P-region and the N-region are heavily doped
2. The N-region is heavily doped compared to the P-region
3. The P-region is heavily doped compared to the N-region
4. An intrinsic silicon region is inserted between the P-region and the N-region

Answer 1

Correct Answer - Option 1 : Both the P-region and the N-region are heavily doped

A negative differential resistance region is observed if both the P and N regions are heavily doped. One such example is the tunnel diode.