Natalia Grishina

Total internal reflection microscopy with a multilayered interface: a light scattering model based on a discrete sources method

The discrete sources method has been extended to analyse P or S polarized evanescent wave scattering by a dielectric particle located on a layered interface. This was done to develop a light scattering simulation model for total internal reflection microscopy. The influence of metallic layers on the prism surface is investigated. Numerical results for the objective response versus particle height and the scattering cross-section are presented.

Analysis of the extreme scattering effect for particles inside and above a noble metal film via the discrete sources method

In this paper the discrete sources method is applied to analyze the extreme scattering effect for particles located both inside and on a gold film deposited on a glass prism. The extreme scattering effect is an effect of the sharp increase of the scattered intensity for P-polarized excitation which occurs in the evanescent wave region behind the critical angle. Moreover, the intensity enhancement appears not only in the transmission direction but in the backscattering direction as well. The effect does not depend on the thickness of the metal film or particle diameter, but it is strongly affected by the film material. Different scattering characteristics, such as transmission cross section and reflection cross sections and their correlation with the surface plasmon resonance in the film, are investigated and discussed in this paper. The analysis of the influence of a thin transparent spacer layer between particle and gold film on the scattering characteristics has been performed. The differential scattering cross section is considered to examine the field distribution in the forward and backscattering directions.

New scheme of the Discrete Sources Method for investigation of a near field enhancement by coupled particles

Article history: Numerical scheme of the Discrete Sources Method has been modified to examine near fields for the polarized light scattering by two coupled noble metal particles. The new scheme enables to compute a near field enhancement of several orders with high accuracy degree. The developed computer model has been employed to investigate plasmonic resonance of two prolate spheroids. Both the electric field intensity between coupled particles and the Scattering Cross-Section have been examined versus particle distance and particles aspect ratio.

Total internal reflection microscopy: examination of competitive schemes via discrete sources method

The discrete sources method has been applied to perform a computer simulation analysis of different total internal reflection microscopy schemes. It has been found that the positioning of the objective lens beneath a glass prism can provide a considerable advantage for determination of the particle–film distance.

Modeled and measured scatter from vias

This paper briefly reviews the use of a verified model to investigate light scatter metrology to detect the presence of defects in semiconductor circuit vias. Three types of defects are examined. Although defects can be detected, there are practical problems associated with separating defects from acceptable changes in dielectric film thickness.