Fourier ellipsometry – an ellipsometric approach to Fourier scatterometry

Abstract

An extension of Fourier scatterometry is presented, aiming at increasing the sensitivity by measuring the phase difference between the reflections polarized parallel and perpendicular to the plane of incidence. The ellipsometric approach requires no additional hardware elements compared with conventional Fourier scatterometry. Furthermore, incoherent illumination is also sufficient, which enables spectroscopy using standard low-cost light sources.

Metrology of Nanostructures by Tomographic Mueller-Matrix Scatterometry

“…In addition, optical scatterometry is mostly suitable for measuring repetitive dense structures, but infeasible for the measurement of isolated or generally non-periodic structures. To address the challenges or limitations in conventional optical scatterometry, several designs have been presented with the idea of trying to collect the scattering information about the nanostructure under test conditions as much as possible, such as with the goniometric optical scatter instrument [12][13][14], through-focus scanning optical microscopy [15], scatterfield microscopy [16], tomographic diffractive microscopy [17,18], and Fourier scatterometry [19,20]. Recently, we have also developed a novel instrument called the tomographic Mueller-matrix scatterometer (TMS) [21].…”