Extended and localized surface plasmons in annealed Au films on glass substrates

Abstract

We present here a study on the surface plasmon resonance (SPR) in Au films deposited onto glass substrates and annealed in air at different temperatures. The initial Au films exhibit the resonant absorption of extended surface plasmons which depends on the film thickness. Thermal treatments promote the modification of the continuous films toward the formation of Au isolated islands. The morphological features of the islands depend on the film initial thickness and annealing temperature. The optical properties of the films are qualitatively modified as a consequence of the morphological changes. For films with initial thickness below 30 nm, the islands exhibit localized SPR while thicker films lead to islands large enough to hold extended SPR.

Substrate-induced strain in carbon nanodisks

“…The RMS increased to 48.1 nm. This effect is similar to the roughening observed in annealed Au thin films [9,10]. AFM measurements performed on the nanostructures supported by the asdeposited gold substrate revealed that in most cases the carbon nanodisks are not completely flat.…”

Modified Au-Based Nanomaterials Studied by Surface Plasmon Resonance Spectroscopy

“…94 Therefore, we focus our study on the effect of initial thickness and annealing temperature. 12 In AFM images, we could observe that all as-grown films presented a continuous structure, while after annealing Au films exhibited a discontinuous structure with a similar Grain size distribution results very broad, with grains in the range from 100 to 400 nm.…”

“…Concretamente, para películas con espesores menores de 30 nm, las nanoestructuras obtenidas tras el tratamiento térmico exhiben LSPs mientras que para las películas con espesores mayores, las islas de Au son lo suficientemente grandes (dimensiones más grandes que la longitud de onda de la luz visible) y ESPs pueden ser excitados. 12 Por otro lado, para el caso de las bicapas Au/Fe,éstas son crecidas sobre substratos de sílice bajo diferentes configuraciones y posteriormente son tratadas térmicamente en aire o bajo vacío, bajo diferentes condiciones del tratamiento. Los tratamientos térmicos de bicapas suponen un nuevo método de fabricación de nano y microestructuras complejas que es presentado aquí por primera vez.…”

“…In Chapter 3, variations of SPs in Au thin films annealed in air at different temperatures are studied, changing the initial film thickness. 12 In Chapter 4, we show the fabrication of Au/FeO x NPs over silica substrates from thin films and bilayers evaporated and treated thermally. Subsequently, SPR modifications are studied changing the film thickness, configuration of samples and annealing conditions.…”

“…Specifically, for films with initial thickness below 30 nm, upon annealing, the Au NPs exhibit LSPs while thicker films lead to large islands (dimensions larger than visible light wavelength) that can exhibit ESPs. 12 On the other side, for the case of Au/Fe bilayers, these are grown on silica substrates under various configurations and annealed in air or low vacuum at different conditions of the thermal treatments. Bilayer annealing represents a new method to fabricate large areas of complex nano and microparticles, which we present here for the first time.…”