TY - CONF A1 - Bresch, Sophie A1 - Höhne, Patrick A1 - Mieller, Björn A1 - Koppert, Ralf A1 - Rabe, Torsten T1 - Commercial LTCC for thin film deposition N2 - Low-temperature co-fired ceramics (LTCC) are used to fabricate multilayer circuits which are robust in harsh environments. Thick-film technology is well established for the metallization of circuit boards and microsystems. For specific sensor applications, the combination of LTCC and thin-film technology is advantageous to reach higher structure resolutions. Due to the high roughness of as-fired LTCC surfaces compared with silicon-wafers, the deposition of low-defect- films with narrowly specified properties is challenging. There is spare literature about thin films on commercial LTCC comparing different material systems or sintering techniques. For developing thin film sensors on multilayer circuits it is crucial to identify thin-film-compatible commercial LTCC material as well as the crucial surface properties. In this work we evaluate the thin-film capability of different LTCC surfaces. The as-fired surfaces of free-sintered, constrained-sintered (sacrificial tape), and pressure-assisted sintered commercial LTCCs (DP951, CT708, CT800), as well as respective polished surfaces, were analyzed by tactile and optical roughness measurements and scanning electron microscopy. The thin-film capability of the LTCC surfaces was assessed by sheet resistance and temperature coefficient of resistance (TCR) of deposited Ni thin-film layers. Contrary to the expectations, no correlation between roughness and thin-film capability was found. Ni thin films on constrained sintered DP951 show the lowest sheet resistance and highest TCR within the experimental framework of the as-fired surfaces. The influence of surface morphology on the film properties is discussed. T2 - KERAMIK 2022 / 97. DKG-Jahrestagung CY - Online meeting DA - 7.3.2022 KW - Roughness KW - Hydrogen sensor KW - LTCC PY - 2022 AN - OPUS4-54436 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Agea Blanco, Boris A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Günster, Jens T1 - The Effect of Sandblasting on Module Glazing N2 - Surface roughness, RZ, normal transmittance, ΤN, total transmittance, ΤT, and photovoltaic (PV) module efficiency, ηS, were measured for commercial solar glass plates and PV test modules identically sandblasted with different loads of quartz sand (200–400 μm), impact inclination angles, and sand particle speed. Measured data are presented versus the specific energy uptake during sand blasting, E (J/m2). Cracks, adhering particles, and scratch-like textures probably caused by plastic flow phenomena could be observed after sand blasting. Their characteristic size was much smaller than that of sand particles. After blasting and subsequent cleaning, the glass surface was still covered with adhering glass particles. These particles, cracks, and scratch-like textures could not be removed by cleaning. For sand blasting with α = 30° inclination angle and E = 30 000 J/m2, normal transmittance, total transmittance, and relative module efficiency decreased by 29%, 2% and ∽2%, respectively. This finding indicates that diffusive transmission of light substantially contributes to PV module efficiency and that the module efficiency decrease caused by sand erosion can be better estimated from total than by normal transmittance measurements. T2 - 7th SOPHIA PV-Module Reliability Workshop CY - Freiburg, Germany DA - 06.06.2017 KW - Photovoltaic Module KW - Sandstorm KW - Erosion KW - Sandblasting KW - Transmittance KW - Roughness KW - Efficiency PY - 2017 AN - OPUS4-42861 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bruno, Giovanni A1 - Thiede, Tobias A1 - Serrano Munoz, Itziar A1 - Léonard, Fabien A1 - Farahbod, L. T1 - Computed tomography of LBM produced In625 lattices: Integrity analysis from powder particles to structures N2 - We investigated lattice structure manufactured by laser beam melting with computed tomography on difference scales, such as powder scale, strut scale and lattice scale. The raw powder has been evaluated by means of synchrotron computed tomography (CT) at the BAM-Line (HZB Bessy II, Berlin). Therefore, the particle size distribution and even the pore size distribution was investigated and compared with results received by the producer by means of sieving. Studies with laboratory X-ray CT of porosity and roughness of manufactured struts in dependence of the build angle exhibited the tendency that elongated pores appear solely in a certain range near the edge. The integrity and load-bearing capacity of a lattice structure was investigated by means of in-situ CT during compression. The lattice structure was compressed by 10 % in height with an applied maximum force of 5 kN. We applied digital volume correlation algorithm on volumes of different load steps to quantifies the displacement within the structure. T2 - Metallographie-Tagung 2018 CY - Leoben, Austria DA - 19.09.2018 KW - Additive manufacturing KW - Laser beam melting KW - Computed tomography KW - Lattice structures KW - In-situ CT KW - Porosity KW - Roughness PY - 2018 AN - OPUS4-45998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -