Abstracts

In optical imaging there is always a push toimprove image quality or find methods to gain new imaginginformation. This is apparent in the optical lithography andsemiconductor inspection industries, where optical metrology andimaging systems are using larger numerical aperture systems andfinding new imaging methods, such as immersion imaging, to shrinkfocal fields. At high numerical apertures, scalar diffractiontheories break down and polarization effects play a large role infocal field interactions. With this interest in polarization, newmodels for local polarization effects are needed. Along with newmodels, cylindrically-symmetric polarized beams known ascylindrical vector (CV) beams, can provide new methods of imagingin this high NA regime.
In this thesis, weexamine the modeling of radially and azimuthally polarized beamsfocused at high numerical aperture in the presence of a planarinterface. These focal fields are also modeled with primaryspherical, coma, and astigmatism wavefront aberrations in theentrance pupil of the focusing system. Particular attention isgiven to the longitudinal field component generated by the focusedradial beam, and the correlation between the magnetic and electricfields of radial and azimuthal beams.
Ascanning edge test using linearly polarized beams is modeled usinga rigorous coupled wave (RCW) method and is compared toexperimental data. The ability of the scanning edge test to predictspot asymmetry is investigated though the comparison of the RCWscanning edge model with free space vector diffraction theories.This RCW model is extended to include CV beam illumination and modefiltering of the system's exit pupil fields. This extensionprovides a model to accurately predict the performance of adark-field imaging modality using radially and azimuthallypolarized beams. Predictions from this model are compared toexperimental results with attention given to defocus effects andthe ability to accurately measure edge separation.
Longitudinal fields from focused radiallypolarized beams are shown to be the dominant source of surfacesecond harmonic generation (SHG) when compared to azimuthally andlinearly polarized pupil fields. The longitudinal field from afocused radially polarized beam is used for imaging and the abilityto image edge structures is compared to bright-field imaging.Finally, an overview of completed research is given and a list ofproposed future research is presented.