Light Scattering Ellipsometry:

The polarization of scattered light can often indicate the source of that scattered light. Using Light Scattering Ellipsometry, whereby the polarization of light scattered into directions out of the plane of incidence is measured for a fixed incident polarization, scattering from microroughness, subsurface defects, and particulate contamination can be distinguished. Experimental measurements and theoretical modeling have been carried out to demonstrate this effect in a variety of systems:

Roughness of a single material (silicon, glass, steel, and titanium nitride)

Subsurface defects (fused silica, glass ceramic, and subsurface defects in silicon)

Roughness of a dielectric layer (SiO₂ and polymer films on silicon)

Particles above a single interface (polystyrene, copper, and gold spheres on silicon)

Particles above a thin film (polystyrene spheres on polystyrene films on silicon)

Special-effect pigmented coatings (metallic and pearlescent flakes)

Overlay structures

Placing the technique on a firm metrological basis, so that it is quantitatively accurate, is a high priority of the program. Polarized light scattering in the Stokes-Mueller representation is also studied.