**Statement I:** When a Si sample is doped with Boron, it becomes P-type and when doped by Arsenic it becomes N-type semiconductor such that P-type has excess holes and N-type has excess electrons.
**Statement II:** When such P-type and N-type semiconductors 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.
Answer: (D) Statement I is correct but Statement II is incorrect
Boron (trivalent) gives a p-type and arsenic (pentavalent) an n-type semiconductor: Statement I is correct.
At an unbiased junction the diffusion and drift currents balance, so no net current flows through an external ammeter: Statement II is incorrect.
Solution by Sreeraj P, M.Sc Physics