GATE EC 2025 Set 1 — Question 31

MSQ+1 / -0EasyIntrinsic & Extrinsic SemiconductorsSemiconductor PhysicsElectronic DevicesFermi Level & Doping

Electronic Devices → Semiconductor Physics → Fermi Level & Doping

Last updated 5 September 2026

Question

Which of the following can be used as an n-type dopant for silicon? Select the correct option(s).

Correct answer (A) Arsenic; (D) Phosphorous Solution Arsenic (As) and Phosphorus (P) are Group V elements. When added to Silicon (Group IV), they provide an extra valence electron, creating an n-type semiconductor. Boron (B) and Gallium (Ga) are Group III elements, which create holes and result in p-type semiconductors. Turn this into a strength. Explore AI-powered practice and doubt support with Success Tracker.

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Correct answer (A) Arsenic; (D) Phosphorous Solution Arsenic (As) and Phosphorus (P) are Group V elements. When added to Silicon (Group IV), they provide an extra valence electron, creating an n-type semiconductor. Boron (B) and Gallium (Ga) are Group III elements, which create holes and result in p-type semiconductors.

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