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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Determining the Optimized Layer-by-Layer Film Architecture With Dendrimer/Carbon Nanotubes for Field-Effect Sensors

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Autor(es):
Sousa, Marcos A. M. ; Siqueira, Jr., Jose R. ; Vercik, Andres ; Schoening, Michael J. ; Oliveira, Jr., Osvaldo N.
Número total de Autores: 5
Tipo de documento: Artigo Científico
Fonte: IEEE SENSORS JOURNAL; v. 17, n. 6, p. 1735-1740, MAR 15 2017.
Citações Web of Science: 2
Resumo

The capacitive electrolyte-insulator-semiconductor (EIS) structure is a typical device based on a field-effect sensor platform. With a simple silicon-based structure, EIS have been useful for several sensing applications, especially with incorporation of nanostructured films to modulate the ionic transport and the flat-band potential. In this paper, we report on ion transport and changes in flat-band potential in EIS sensors made with layer-by-layer films containing poly(amidoamine) (PAMAM) dendrimer and single-walled carbon nanotubes (SWNTs) adsorbed on p-Si/SiO2/Ta2O5 chips with an Al ohmic contact. The impedance spectra were fitted using an equivalent circuit model, from which we could determine parameters such as the double-layer capacitance. This capacitance decreased with the number of bilayers owing to space charge accumulated at the electrolyte-insulator interface, up to three PAMAM/ SWNTs bilayers, after which it stabilized. The charge-transfer resistance was also minimum for three bilayers, thus indicating that this is the ideal architecture for an optimized EIS performance. The understanding of the influence of nanostructures and the fine control of operation parameters pave the way for optimizing the design and performance of new EIS sensors. (AU)

Processo FAPESP: 13/14262-7 - Filmes nanoestruturados de materiais de interesse biológico
Beneficiário:Osvaldo Novais de Oliveira Junior
Modalidade de apoio: Auxílio à Pesquisa - Temático