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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 an electron is a transition from the valence band to the conduction band and recombination leads to a reverse transition.
Auger recombination is a similar Auger effect which occurs in semiconductors. An electron and electron hole (electron-hole pair) can recombine giving up their energy to an electron in the conduction band, increasing its energy. The reverse effect is known as impact ionization.
The electron and hole bulk recombination lifetimes, and , in bulk GaAs are of the order of 10−8 s, about 2 orders of magnitude smaller than those in bulk silicon. Surface recombination reduces the power efficiency of the TPP effect as the electrons and holes recombine before they are collected at the contacts.
The presence of a missing covalent bond allows the bonded electrons of neighboring atoms to move into the "hole", leaving another hole behind, thus propagating holes throughout the lattice in the opposite direction to the movement of the negatively electrons. It can be said that photons absorbed in the semiconductor create electron-hole pairs.
An exciton is a bound state of an electron and an electron hole which are attracted to each other by the electrostatic Coulomb force resulting from their opposite charges. It is an electrically neutral quasiparticle regarded as an elementary excitation primarily in condensed matter, such as insulators, semiconductors, some metals, and in some liquids.
When an electron leaves a helium atom, it leaves an electron hole in its place. This causes the helium atom to become positively charged. In physics, chemistry, and electronic engineering, an electron hole (often simply called a hole) is a quasiparticle denoting the lack of an electron at a position where one could exist in an atom or atomic lattice.
Recombination between electrons and holes is detrimental in a solar cell, so designers try to minimize it. However, radiative recombination—when an electron and hole recombine to create a photon that exits the cell into the air—is inevitable, because it is the time-reversed process of light absorption.
When the semiconductor absorbs a photon with energy equal to or greater than the material's band gap, an electron excites from the valence band to the conduction band, generating a electron hole in the valence band. This electron-hole pair is an exciton. [21] The excited electron and hole can recombine and release the energy gained from the ...