Grazing incidence and grazing exit X-ray fluorescence: principles, techniques, and applications for thin film and nanostructure analysis

Abstract

In various technological fields, different nanomaterials are being used to push toward ever smaller and more complex structures. Different X-ray based methods can be extremely helpful to develop, analyze and improve such materials. Combining element sensitivity with lateral in-depth resolution, grazing incidence X-ray fluorescence (GIXRF) is a perfect candidate for this task. GIXRF represents an extension of standard X-ray fluorescence analysis (XRF) and total reflection XRF, and its utility has been demonstrated in a number of synchrotron studies over the years. Especially with improvements in X-ray sources and X-ray optics, GIXRF has become accessible to laboratory setups as well. Based on the principle of reciprocity, grazing emission – or gazing exit X-ray fluorescence (GEXRF) was postulated and proven to work in a similar way as GIXRF, with different advantages and disadvantages due to the inverse geometry. However, with their comparably more complex analysis procedures GIXRF and GEXRF methodologies are not yet widespread in research and industry. Thus, this review aims to give a comprehensive overview on the physical principle, technical requirements and recent applications in research and industry of these versatile nanoscale characterization methods.