CUET · PHYSICS · PYQ PAPER 2025
On adding a small amount of boron to a silicon crystal
- A boron becomes a donor atom
- B its resistance is increased
- C it becomes a n-type semiconductor
- D it becomes a p-type semiconductor
Answer & Solution
Correct Answer
(D) it becomes a p-type semiconductor
Step-by-step Solution
Detailed explanation
Boron is a trivalent impurity ( 3 valence electrons), so when added to tetravalent silicon ( 4 valence electrons), it creates "holes" as majority charge carriers. This process of doping significantly decreases resistance and forms a p-type (positive-type) semiconductor. D) it…
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