Table of Contents
Holes:
The vacancy or absence of an electron in the bond of a covalently bonded crystal is called a hole. In terms of band theory, whenever an electron is removed from the completely filled valence band of a semiconductor, a vacancy is left behind in the valence band. This vacancy serves as a positive charge carrier and is called a hole.
A hole is not a physical entity. A hole is a convenient way of describing charge motion, though the motion can be described entirely in terms of electrons.
Characteristics of holes:
1. A hole is just a vacancy created by the removal of an electron from a covalent bond of semiconductor.
2. It has the same mass as the (removed) electron.
3. It is associated with a positive charge of magnitude e.
4. The energy of a hole is higher, the farther below it is from the top of the valence band.