Organic semiconductor

An organic semiconductor is an Organic compound that exhibits similar properties to inorganic semiconductors. That is the presence of a hole and electron conduction layer and a band gap. As with inorganic amorphous semiconductors, localized states, mobility gaps, and photon-assisted hopping also contribute to conduction. Like inorganic semiconductors, organic semiconductors can be doped. Highly doped organic semiconductors, for example Polyaniline (Ormecon) and , are also known as Organic metals.

Related Topics:
Organic compound - Inorganic - Semiconductors - Electron - Band gap - Mobility gap - Photon-assisted hopping - Doped - Polyaniline

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Two kinds of carriers mediate conductivity in organic semiconductors. These are π-electrons and unpaired electrons.

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Almost all organic solids are insulators. However, when their constituent molecules have π-conjugate systems, electrons can move via π-electron cloud overlaps. Polycyclic aromatic hydrocarbons and phthalocyanine salt crystals are examples of this type of organic semiconductor.

Related Topics:
Insulator - π-conjugate - π-electron cloud - Aromatic hydrocarbon - Phthalocyanine

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In some organic molecules, even unpaired electrons can stay stable for a long time. In such cases, unpaired electrons will be the carriers. This type of semiconductor is also obtained by pairing an electron donor molecule and an electron acceptor molecule and is called a charge transfer complex.

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The study of a charge-transfer complexes began with the discovery of the strikingly high conductivity of perylene-iodine complex (8 Ωcm) in 1954. In 1972, the TTF-TCNQ complex, whose conductivity is metallic, was synthesized. In 1980, superconductivity was observed in TMTSF-PF6 complex.

Related Topics:
Perylene-iodine complex - 1954 - 1972 - TTF-TCNQ complex - 1980 - Superconductivity

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McGinness, Corry, and Proctor reported a high conductivity state in a polyacetylene (melanin) and the first organic electronic device. This was a voltage-controlled switch (Science, vol 183, 853-855 (1974)). Their original "gadget" is now in the Smithsonian's collection of early electronic devices.

Related Topics:
Polyacetylene - Melanin - Smithsonian

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Organic semiconductors are attractive as active elements in optoelectronic devices such as light emitting diodes (LED), solar cells, field effect transistors (FET), electrochemical transistors and recently also in biosensing applications.

Related Topics:
Optoelectronic - Light emitting diode - Solar cell - Field effect transistor

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There are many strong points of organic semiconductors, such as easy fabrication, mechanical flexibility, and low cost. Melanin is a semiconducting polymer currently of high interest to researchers in the field of organic electronics in both its organic and synthesized forms.

Related Topics:
Melanin - Organic electronics

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Both short chain oligomers and long chain (polymers) organic semiconductors are known. Typical examples for semiconducting oligomers are: pentacene, anthracene and rubrene. Some semiconducting polymers are: Poly(3-hexylthiophene), Poly(p-phenylvinylene) and F8BT.

Related Topics:
Oligomer - Polymers - Pentacene - Anthracene - Rubrene - Poly(3-hexylthiophene) - Poly(p-phenylvinylene)

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