MCQ
Hole is:
- AAn anti-particle of electron.
- BA vacancy created when an electron leaves a covalent bond.
- CAbsence of free electrons.
- DAn artifically created particle.
✓
Answer
- A vacancy created when an electron leaves a covalent bond.
Solution:
Concept of holes in the semiconductor:
- When an electron is removed from a covalent bond, it leaves a vacancy behind. An electron from a neighbouring atom can move into this vacancy, leaving the neighbour with a vacancy. In this way the vacancy formed is called a hole (or cotter), and can travel through the material and serve as an additional current carriers.
- A hole is considered as a seat of positive charge, having magnitude of charge equal to that of an electron.
- Holes acts as a virtual charge, although there is no physical charge on it.
- Effective mass of hole is more than an electron.
- Mobility of hole is less than an electron.
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