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Alineación de cristales líquidos en superficies carbonáceas con orden de orientación.
J Stohr1, M G Samant, J Luning
1IBM Research Division, Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA.
Science (New York, N.Y.)
|June 26, 2001
Resumen
La alineación de los cristales líquidos en las superficies de carbono se logra controlando el orden de los enlaces superficiales. La espectroscopia de estructura fina de absorción de rayos X cercana al borde (NEXAFS) revela cómo el orden de orientación dirige la alineación de los cristales líquidos.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Ciencias de la superficie Ciencias de la superficie.
- Física de la materia condensada Física de la materia condensada
Sus antecedentes:
- Las capas de alineación de cristales líquidos (LC) son cruciales para las tecnologías de visualización.
- Las superficies carbonáceas son candidatos potenciales para las capas de alineación de LC.
- Comprender la relación entre las propiedades de la superficie y la alineación de LC es esencial.
Objetivo del estudio:
- Para investigar el vínculo entre el orden de enlace de orientación en superficies carbonáceas y la dirección de alineación de los cristales líquidos.
- Establecer la base científica para el uso de películas amorfas de carbono como capas de alineación de LC.
Principales métodos:
- Se utilizó la espectroscopia de estructura fina de absorción de rayos X de borde cercano (NEXAFS).
- Se analizaron tres tipos de superficies carbonáceas: poliimida frotada, poliimida irradiada con haz de iones y películas de carbono tipo diamante irradiadas con haz de iones.
Principales resultados:
- Demostró una correlación directa entre el orden de enlace de orientación en la superficie carbonácea y la dirección de alineación de la LC.
- Se demostró que la alineación de LC puede inducirse en prácticamente cualquier sustrato carbonáceo mediante el orden de orientación de la superficie de ingeniería.
Conclusiones:
- El orden de orientación de la superficie es el factor clave que determina la dirección de alineación de LC en sustratos carbonosos.
- El tratamiento direccional de haces de iones de baja energía de películas amorfas de carbono puede crear capas efectivas de alineación de LC.
- Esta investigación proporciona una base para el desarrollo de materiales avanzados de alineación LC.
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