The breakdown in a reverse-biased p-n junction is more likely to occur due to 
 

a. the large velocity of the minority charge carriers if the doping concentration is small
b. the large velocity of the minority charge carriers if the doping concentration is large
c. strong electric field in a depletion region if the doping concentration is small
d. strong electric field in the depletion region if the doping concentration is large



1. (a, d)

2. (b, d)

3. (c, d)

4. (b, c)

(1) Hint: The breakdown in the reverse-biased p-n junction depends on the no. of charge carriers.
In reverse biasing, the minority charge carriers will be accelerated due to reverse biasing, which on striking with atoms cause ionization resulting in secondary electrons and thus more number of charge carriers.
When doping concentration is large, there will be a large number of ions in the depletion region, which will give rise to a strong electric field.