A MODEL IN SNOM - INFLUENCE OF METALLIZAT ION AND OF TIP GEOMETRY

Recently, various versions of Scanning Near-Field Optical Microscopes (SNOM) have been developed, pushing the limits of lateral resolution b eyond the Rayleigh criterion: lambda/30 almost-equal-to 20 nm have bee n reached. Unfortunately, images obtained by SNOM depend strongly on t he experimental conditions (angle of incidence, polarization, incidenc e plane direction, sample nature...) Theoretical studies are thus nece ssary for interpreting experimental data. In a previous work, we propo sed a model based on a perturbative resolution of Maxwell equations. H ere, we extend this work to more complex samples (multilayers) and to more general tip geometries. Moreover, this model can be used for vari ous SNOM configurations and take the sample-tip electromagnetic coupli ng into account.