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Soft Lithographic Functionalization and Patterning Oxide-free Silicon and Germanium
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Formación y caracterización paso a paso de las arquitecturas multiporfirina-imida enlazadas covalentemente en Si
Jieying Jiao1, Franklin Anariba, Hugo Tiznado
1Department of Chemistry, University of California, Riverside, CA 92521-0403, USA.
Journal of the American Chemical Society
|May 25, 2006
Resumen
Los investigadores desarrollaron un nuevo método para la síntesis gradual de oligómeros de porfirina en superficies de silicio. Esta técnica crea películas moleculares de alta densidad de carga para su uso potencial en dispositivos electrónicos avanzados.
Área de la Ciencia:
- La electrónica molecular es la electrónica molecular.
- Ciencia de los materiales ciencia de los materiales.
- Química de las superficies.
Sus antecedentes:
- La fabricación de arquitecturas moleculares complejas en superficies electroactivas es crucial para los sistemas híbridos moleculares / semiconductores.
- Desarrollar métodos controlados para construir ensamblajes moleculares atados a la superficie es un desafío continuo.
Objetivo del estudio:
- Desarrollar un método fácil para la síntesis gradual de oligómeros de porfirina en superficies de Si{100}.
- Para caracterizar las propiedades de las películas de porfirina ultrafinas y de alta densidad de carga resultantes.
Principales métodos:
- Síntesis paso a paso utilizando reacciones formadoras de imida entre una unidad base de triallilo-porfirina y alternando dianhidrido y porfirina-diamina.
- Técnicas de caracterización que incluyen métodos electroquímicos, espectroscopia de infrarrojos con transformación de Fourier (FTIR), espectroscopia de fotoelectrones de rayos X (XPS), microscopía de fuerza atómica (AFM) y ellipsometría.
Principales resultados:
- El crecimiento gradual exitoso de los oligómeros de porfirina (2-5 porfirinas) en Si{100} a través de enlaces de imida.
- Se ha demostrado una alta densidad de carga y un grosor relativamente bien controlado de las películas ultrafinas de multiporfirina.
- Caracterizó la morfología, el crecimiento y el grosor de la película utilizando una combinación de técnicas espectroscópicas y microscópicas.
Conclusiones:
- La reacción de formación de imida desarrollada permite la construcción gradual y controlada de oligómeros de porfirina atados a la superficie.
- Estas películas de multiporfirina exhiben una alta densidad de carga, lo que las hace prometedoras para dispositivos de almacenamiento de información molecular.
- Este enfoque de abajo hacia arriba complementa la litografía de arriba hacia abajo para la fabricación de dispositivos a nanoescala.
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