The utilization of nanostructured materials for modern applications gained more and more importance during the last few
years. As examples super-fluorescent quantum dots, the use of carbon nano tubes (CNTs) in microelectronics,
electrospun fibers in filter membranes, thin film coatings for solar cells, mirrors or LEDs, semiconductor electronics, and
functionalized surfaces may be named to address only a few topics. To optimize the systems and enable the full range of
capabilities of nanostructures a thorough characterization of the surface-near topography (e.g. roughness, thickness,
lateral dimension) as well as of the chemical composition is essential.
As a versatile tool for spatial and chemical characterization XUV reflectometry, scatterometry and diffractometry is
proposed. Three different experimental setups have been realized evaluating spectral resolved reflectance under constant
incidence angle, angular resolved reflectance at a constant wavelength, or a combined approach using laboratory scaled
XUV sources to gain insight into chemical composition, film thickness and surface/interface roughness. Experiments on
near-edge X-ray absorption fine structure spectroscopy (NEXAFS) at the carbon K-edge have been performed. The
investigated systems range from synthetic polymers (PMMA, PI) over organic substances (humic acids) to biological
matter (lipids), delivering unique spectra for each compound. Thus NEXAFS spectroscopy using a table-top XUV source
could be established as a highly surface sensitive fingerprint method for chemical analysis. Future extended experiments
will investigate the silicon L-edge where e.g. silicon oxide interlayers below high-k or other nano-layered material on Sisubstrates
depict a technological important group of composite systems.
The use of extreme ultraviolet radiation (XUV/EUV) enables a variety of new optical and analytical techniques such as EUV-lithography,
-microscopy but also -reflectometry. Due to the strong interaction of XUV with matter, grazing-incidence reflectometry in the 1-40 nm range has proven to be a surface sensitive technique to characterize
thin-film structures on the nanometer scale. Chemical composition, thickness and surface roughness of a deposited layer system can be determined indirectly from its reflectivity curve by non-linear regression techniques and the combined Nevot Croce- and general transfer matrix formalism for X-ray reflectivity. Here the reflectivity can either be determined as a function of incident wavelength at a fixed grazing angle or vice versa. This way it is even possible to specify a root-mean-square (rms) surface roughness of hidden layer-interfaces in the depth of a stack. To date, such measurements in the XUV have only been carried out at synchrotron facilities prohibiting an easy access to a broad range of users. Taking into account the recent progress in the development of short wavelength sources and optics, laboratory-scale, plasma-based XUV light-sources are becoming an attractive option for compact devices. Along with our simulations we present our experimental work on an off-synchrotron XUV-reflectometer for characterization of thin-film structures. The device can also be utilized to carry out scattered light measurements from ultra smooth surfaces, e.g. wafers, for defect inspection.