Semiconductors Question 4
Question 4 - 25 January - Shift 2
Statement I : When a Si sample is doped with Boron, it becomes $P$ type and when doped by Arsenic it becomes N-type semi conductor such that P-type has excess holes and $N$-type has excess electrons.
Statement II : When such P-type and N-type semi-conductors, are fused to make a junction, a current will automatically flow which can be detected with an externally connected ammeter.
In the light of above statements, choose the most appropriate answer from the options given below.
Options:
(1) Both Statement I and statement II are incorrect
(2) Statement I is incorrect but statement II is correct
(3) Both Statement I and statement II are correct
(4) Statement I is correct but statement II is incorrect
Show Answer
Answer: (4)
Solution:
Statement $-I$ is correct
When $P-N$ junction is formed an electric field is generated form $N$-side to $P$-side due to which barrier potential arises \& majority charge carrier can not flow through the junction due to barrier potential so current is zero unless we apply forward bias voltage.
