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Question
Hole is ______.
Options
an anti-particle of electron.
a vacancy created when an electron leaves a covalent bond.
absence of free electrons.
an artifically created particle.
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Solution
Hole is a vacancy created when an electron leaves a covalent bond.
Explanation:
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 carrier.
- A hole is considered a seat of positive charge, having a magnitude of charge equal to that of an electron.
- Holes act as a virtual charge, although there is no physical charge on them.
- The effective mass of a hole is more than an electron.
- The mobility of a hole is less than an electron.
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