Diffusion length of singlet excitons in copper phthalocyanine films

Ryszard Signerski, Grazyna Jarosz

Abstract


The work presents a method of extraction of exciton diffusion length from photocurrent spectrum measurements. A copper phthalocyanine (CuPc) layer was taken into consideration as an example. Samples were made in a high vacuum system by subsequent evaporation of the following layers: N, N’-dimethyle-3,4,9,10-perylenbis(dicarboximide) (MePTCDI) and CuPc and Au onto glass/ITO substrate. The subject of our investigation was a saturation photocurrent generated by exciton dissociation at MePTCDI/CuPc interference. As a result of our analysis, the product of quantum efficiency of exciton dissociation and charge carrier collection and exciton diffusion length was estimated and it yielded 1.6nm.

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Photonics Letters of Poland - A Publication of the Photonics Society of Poland
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ISSN: 2080-2242