P-N Junction Diode
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 ameter. In the light of above statements, choose the most appropriate answer from the options given below
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Answer: (c)
- Statement I: Boron (trivalent) gives p-type with excess holes; Arsenic (pentavalent) gives n-type with excess electrons. Correct.
- Statement II: After junction formation, diffusion builds a barrier that stops further net flow; no current flows in an unbiased junction. Incorrect.
- So the answer is (c).