CuInSe2 quantum dots grown by molecular beam epitaxy on amorphous SiO2 surfaces

The currently most efficient polycrystalline solar cells are based on the Cu(In,Ga)Se compound as a light absorption layer. However, in view of new concepts of nanostructured solar cells, CuInSe nanostructures are of high interest. In this work, we report CuInSe nanodots grown through a vacuum-compa...

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Detalles Bibliográficos
Autores: Limborço, H., Salomé, P. M. P., Ribeiro-Andrade, R., Teixeira, J. P., Nicoara, Nicoleta, Abderrafi, Kamal, Leitão, Joaquim P., González, J. C., Sadewasser, Sascha
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/202922
Acceso en línea:http://hdl.handle.net/10261/202922
Access Level:acceso abierto
Palabra clave:Copper indium gallium selenide (CuInSe2)
Quantum dots
Descripción
Sumario:The currently most efficient polycrystalline solar cells are based on the Cu(In,Ga)Se compound as a light absorption layer. However, in view of new concepts of nanostructured solar cells, CuInSe nanostructures are of high interest. In this work, we report CuInSe nanodots grown through a vacuum-compatible co-evaporation growth process on an amorphous surface. The density, mean size, and peak optical emission energy of the nanodots can be controlled by changing the growth temperature. Scanning transmission electron microscopy measurements confirmed the crystallinity of the nanodots as well as chemical composition and structure compatible with tetragonal CuInSe. Photoluminescence measurements of CdS-passivated nanodots showed that the nanodots are optoelectronically active with a broad emission extending to energies above the CuInSe bulk bandgap and in agreement with the distribution of sizes. A blue-shift of the luminescence is observed as the average size of the nanodots gets smaller, evidencing quantum confinement in all samples. By using simple quantum confinement calculations, we correlate the photoluminescence peak emission energy with the average size of the nanodots.