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Generalized Einstein relation for disordered semiconductors - implications for device performance

Yohai Roichman·Nir Tessler
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Abstract

The ratio between mobility and diffusion parameters is derived for a Gaussian-like density of states. This steady-state analysis is expected to be applicable to a wide range of organic materials (polymers or small molecules) as it relies on the existence of quasi-equilibrium only. Our analysis shows that there is an inherent dependence of the transport in trap-free disordered organic-materials on the charge density. The implications for the contact phenomena and exciton generation rate in light emitting diodes as well as channel-width in field-effect transistors is discussed.

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Yohai Roichman, Nir Tessler. 2004-02-03. Generalized Einstein relation for disordered semiconductors - implications for device performance. https://doi.org/10.1063/1.1461419

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