What is hole current in a semiconductor?

Holes and electrons are the two types of charge carriers responsible for current in semiconductor materials. A hole is the absence of an electron in a particular place in an atom. Although it is not a physical particle in the same sense as an electron, a hole can be passed from atom to atom in a semiconductor material.

What is hole current flow in semiconductor?

In conductors current is caused by only motion of electrons but in semiconductors current is caused by both electrons in conduction band and holes in valence band. Current that is caused by electron motion is called electron current and current that is caused by hole motion is called hole current.

Why are holes current?

Solution : A p-type semiconductor has holes as majority carriers and during conduction, the electron jumps from nearby covalent bond to occupy the hole and thus the hole shifts towards covalent bond from which the electron has jumped. This movement of hole is called hole current.

How do holes conduct current in a semiconductor?

The free electron and hole both contribute to conduction about the crystal lattice. That is, the electron is free until it falls into a hole. This is called recombination. If an external electric field is applied to the semiconductor, the electrons and holes will conduct in opposite directions.

How hole is created during current flow?

When each electron leaves its position in the valence band, a hole is created – which can be considered as a unit of positive charge (not negative is positive, right?).

Holes amd hole current in semiconductors

What do you mean by hole?

noun. an opening through something; gap; aperture: a hole in the roof; a hole in my sock. a hollow place in a solid body or mass; a cavity: a hole in the ground. the excavated habitation of an animal; burrow.

What is the difference between a hole and a free electron in a semiconductor?

Solution : (i) Electron is a negatively charged particle having charge `=1.6 xx 10^(-19)C`. Hole is a seat having positive charge which is produced when an electron breaks away from a covalent bond in a semiconductor. Hole is having the same charge as that of electron.

Why hole is heavier than electron?

Based on the relation E = mc^2 , Energy of hole is greater than that of electron, thus holes have mass greater than that of electrons.

Why are holes positively charged?

Holes are considered positively charged because of the relation between their velocity and the electric current: when they move right, the current points right. It is theoretically possible to only work in terms of electrons: conduction band electrons and valence band electrons.

What is hole transfer?

1. Charge migration process in which the majority carriers are positively charged.

Why there is no hole current in conductors?

This hole is captured by another free electron. Also, the energy level of free electrons corresponds to the conduction level, hence valance level and conduction level are overlapped. So there are no holes in conduction level to carry hole current.

What is the difference between a hole and electron?

Unlike an electron which has a negative charge, holes have a positive charge that is equal in magnitude but opposite in polarity to the charge an electron has. Holes can sometimes be confusing as they are not physical particles in the way that electrons are, rather they are the absence of an electron in an atom.

Why there is no hole current in good conductors?

In case of conductors, the valence band and the conduction bands overlap. So there are no holes in the conduction band to carry the hole current. Hence there is no hole current in conductors as there is an overlapping of the valence and the conduction bands.

How do holes and electrons flow?

In the presence of an electric field electrons move in one direction and holes appear to move in the opposite direction. Since both electrons and holes carry charge, they both contribute to the conductivity of the material.

Do holes have mass?

Actually holes are simply absence of electrons, note that its the electrons which flow and not the holes, due to the motion of electrons the holes appear to be moving, so thats why holes have the same mass as an electron.

Are holes and protons the same?

First answer: nothing. All protons are identical — same electric charge, mass, spin, magnetic moment, etc.

How electron hole pairs are created in a semiconductor material?

In the semiconductor, free charge carriers (electron-hole pairs) are created by excitation of electron from valence band to the conduction band. This excitation left a hole in the valence band which behaves as positive charge and an electron-hole pair is created.

How do holes carry charge?

In an applied electric field, the electrons move in one direction, corresponding to the hole moving in the other. If a hole associates itself with a neutral atom, that atom loses an electron and becomes positive. Therefore, the hole is taken to have positive charge of +e, precisely the opposite of the electron charge.

Do holes have spin?

But that isn't the whole story: holes have very different spin properties than electrons. Unlike electrons, which are spin 1/2 particles, holes in semiconductors are spin 3/2 quasiparticles. This spin difference means holes react quite differently to an electric field or a magnetic field.

Why energy of hole is higher?

Since more energy is required to remove another electron which is farther from the top of the valence band, therefore, a hole in the valence state farther from the top of the valence band has higher energy, just as a conduction electron farther from the bottom of the conduction band has higher energy.

What is NC in semiconductor?

n = Nc exp[-(Ec-EF)/kT] , where Nc is a temperature dependent constant, called the Effective density of states in the conduction band of the semiconductor. Note that Ec is the edge of conduction band Energy and EF is the Fermi energy level (which appears in the Fermi-Dirac distribution function)

What is meant by electron hole pair?

The electron–hole pair is the fundamental unit of generation and recombination in inorganic semiconductors, corresponding to an electron transitioning between the valence band and the conduction band where generation of electron is a transition from the valence band to the conduction band and recombination leads to a ...

Which electrons are responsible for hole current in silicon?

Electron current in intrinsic silicon is produced by the movement of thermally generated free electrons. Another type of current occurs in the valence band, where the holes created by the free electrons exist.

What is holes in semiconductor Class 12?

In semiconductor materials, holes and electrons are the two types of charge carriers. The holes are formed in the semiconductor material when the electrons in the atoms move out of the valence bond into the conduction band.

What are hole in semiconductor write its characteristics?

Solution : Hole is a seat of positive charge which is produced when an electron breaks away from a covalent bond in a semiconductor. <br> Characteristics of a hole <br> 1. Hole carries a unit positive charge.