MCQ
A p-type semiconductor is:
- APositively charged.
- BNegatively charged.
- ✓Uncharged.
- DUncharged at 0K but charged at higher ternperatures.
✓
Answer
Correct option: C.
Uncharged.
A p-type semiconductor is formed by doping a pure semiconductor with a p-type material. As impurity atoms take the position of the germanium atom in a germanium crystal, three electrons of a p-type material form covalent bonds by sharing electrons with three neighbouring germanium atoms. However, the fourth covalent bond is left incomplete, with a want of one electron. This creates a hole. As the atom as a whole is neutral, the p-type material is also neutral.
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