Question

A positive hole in a semiconductor is

• A. An anti-particle of electron
• B. A vacancy created when an electron leaves a covalent bond
• C. Absence of free electrons
• D. An artificially created particle

Answer 1

The Correct Option is B

In a semiconductor, when an electron gains enough energy, it can leave its covalent bond and become free, leaving behind a "hole." This hole behaves as a positive charge carrier, as the absence of an electron in a covalent bond creates a deficit of negative charge. The hole can move through the semiconductor when neighboring electrons fill the gap. Thus, a positive hole is essentially a vacancy created when an electron leaves its covalent bond, and it acts like a positive charge carrier in the material.

The correct answer is (B) : A vacancy created when an electron leaves a covalent bond.

Answer 2

In a semiconductor, when an electron in the valence band gains sufficient energy (e.g., from thermal excitation), it can jump to the conduction band, leaving behind a vacancy in the valence band. This vacancy is referred to as a "hole."

A hole behaves as if it carries a positive charge, as it represents the absence of a negatively charged electron. The hole can move through the semiconductor as neighboring electrons shift to fill the vacancy, creating the appearance of a positive charge moving through the material.

Thus, a positive hole is not an anti-particle of the electron (which is a different concept related to particle physics), nor is it simply the absence of free electrons or an artificially created particle. It is specifically the vacancy created when an electron leaves its covalent bond.

Therefore, the correct answer is \( {B} \).