TY - JOUR A1 - Senoner, Mathias A1 - Maaßdorf, A. A1 - Rooch, Heidemarie A1 - Österle, Werner A1 - Malcher, M. A1 - Schmidt, M. A1 - Kollmer, F. A1 - Paul, D. A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Unger, Wolfgang T1 - Lateral resolution of nanoscaled images delivered by surface-analytical instruments: application of the BAM-L200 certified reference material and related ISO standards JF - Analytical and bioanalytical chemistry N2 - The certified reference material BAM-L200, a nanoscale stripe pattern for length calibration and specification of lateral resolution, is described. BAM-L200 is prepared from a cross-sectioned epitaxially grown layer stack of AlxGa1–xAs and InxGa1–xAs on a GaAs substrate. The surface of BAM-L200 provides a flat pattern with stripe widths ranging down to 1 nm. Calibration distances, grating periods and stripe widths have been certified by TEM with traceability to the length unit. The combination of gratings, isolated narrow stripes and sharp edges of wide stripes offers plenty of options for the determination of lateral resolution, sharpness and calibration of length scale at selected settings of imaging surface-analytical instruments. The feasibility of the reference material for an analysis of the lateral resolution is demonstrated in detail by evaluation of ToF-SIMS, AES and EDX images. Other applications developed in the community are summarized, too. BAM-L200 fully supports the implementation of the revised International Standard ISO 18516 (in preparation) which is based on knowledge outlined in the Technical Report ISO/TR 19319:2013. KW - AES KW - BAM-L200 KW - CRM KW - EDX KW - Imaging KW - Lateral resolution KW - Sharpness KW - Standardisation KW - STXM KW - ToF-SIMS KW - XPEEM KW - XPS KW - Certified reference material KW - Imaging surface analysis PY - 2015 DO - https://doi.org/10.1007/s00216-014-8135-7 SN - 1618-2642 SN - 1618-2650 VL - 407 IS - 11 SP - 3211 EP - 3217 PB - Springer CY - Berlin AN - OPUS4-33033 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senoner, Mathias A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Imaging surface analysis: Lateral resolution and its relation to contrast and noise JF - Journal of analytical atomic spectrometry N2 - Lateral resolution, also called image resolution, is the most relevant quality parameter of maps and line scans. Therefore well defined procedures for the determination of lateral resolution are required. In the surface analysis community different definitions of lateral resolution are in use and there is no generally accepted method for the determination of lateral resolution which meets the demands of the state-of-the-art in surface analysis. We propose the determination of lateral resolution by imaging of well defined square-wave gratings with finely graded periods. This method enables the real time estimation of lateral resolution and the adjustment of instrument settings with respect to lateral resolution. The effect of noise and contrast on lateral resolution has been analysed by numerically simulated images of square-wave gratings. A new resolution criterion has been developed which is based on the dip-to-noise ratio and takes into account the sampling step width by introducing a "reduced noise". The contrast transfer function has been introduced and its relation to lateral resolution in the presence of noise was analysed. For that reason an "effective cut-off frequency" was defined which is the reciprocal of the lateral resolution. Normalized values of lateral resolution and their relation to signal-to-noise ratio and sampling step width were given for Gaussian and Lorentzian line spread functions. These values enable the calculation of experimental parameters which are necessary to get a required value of lateral resolution. Finally the successful application of the proposed approach to determine lateral resolution has been demonstrated by ToF-SIMS element mapping of the certified reference material BAM-L200. KW - Auflösungskriterium KW - BAM-L200 KW - Effektive cut-off Funktion KW - Laterale Auflösung KW - Kontrast KW - Kontrasttransferfunktion KW - Linienverwaschungsfunktion KW - Rauschen PY - 2010 DO - https://doi.org/10.1039/c004323k SN - 0267-9477 SN - 1364-5544 VL - 25 SP - 1440 EP - 1452 PB - Royal Society of Chemistry CY - London AN - OPUS4-21875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vila-Comamala, J. A1 - Jefimovs, K. A1 - Raabe, J. A1 - Pilvi, T. A1 - Fink, R.H. A1 - Senoner, Mathias A1 - Maaßdorf, A. A1 - Ritala, M. A1 - David, C. T1 - Advanced thin film technology for ultrahigh resolution X-ray microscopy JF - Ultramicroscopy N2 - Further progress in the spatial resolution of X-ray microscopes is currently impaired by fundamental limitations in the production of X-ray diffractive lenses. Here, we demonstrate how advanced thin film technologies can be applied to boost the fabrication and characterization of ultrahigh resolution X-ray optics. Specifically, Fresnel zone plates were fabricated by combining electron-beam lithography with atomic layer deposition and focused ion beam induced deposition. They were tested in a scanning transmission X-ray microscope at 1.2 keV photon energy using line pair structures of a sample prepared by metalorganic vapor phase epitaxy. For the first time in X-ray microscopy, features below 10 nm in width were resolved. KW - X-ray microscopy KW - X-ray diffractive optics KW - Electron-beam lithography KW - Atomic layer deposition KW - BAM-L200 KW - Laterale Auflösung KW - Referenzmaterial KW - Röntgenmikroskopie KW - Zonenplatte PY - 2009 DO - https://doi.org/10.1016/j.ultramic.2009.07.005 SN - 0304-3991 VL - 109 IS - 11 SP - 1360 EP - 1364 PB - Elsevier CY - New York, NY AN - OPUS4-19976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -