LIGHT-SCATTERING FROM MULTILAYER OPTICS .2. APPLICATION TO EXPERIMENT

The tools of investigation presented in part I of this study [J. Opt, Soc. Am. A 11, 197 (1994)] are applied to the analysis of experimental results. First the Limits of the scatterometer are analyzed in detail . Problems of calibration, parasitic light, linearity, and repeatabili ty of measurements are discussed. The roughness spectrum is shown to b e an intrinsic property of surface defects. It is proved that this spe ctrum is perfectly reproduced in the whole range of measurable spatial frequencies by a metallic layer. Dielectric materials under study are TiO2, Ta2O5, and SiO2 obtained by ion-assisted deposition, ion platin g, and electron beam evaporation. The inverse problem is solved with i sotropy degree curves, and the scattering parameters that are low-pass filters and residual spectra are extracted for single layers and mult ilayers. Replication of defects in the measurable bandwidth is shown t o be perfect at all interfaces of a multilayer. In addition, the thin- film materials bring low residual roughnesses. Coatings are also produ ced at oblique deposition, and light scattering is used to detect the oblique growth of the thin-film layers. The role of local defects is i nvestigated.