This publication provides the results of material characterization and binder burnout studies of the commercially available ferrite LTCC (Low Temperature Co-fired Ceramics) tape ESL 40012 used for integrated passive components in LTCC packages. The investigations comprised surface roughness measurements of the fired tape and chemical analysis of the green tapes as well as tapes fired at different peak temperatures by X-ray powder diffraction (XRD) and energy dispersive X-ray spectroscopy (EDXS) analysis. Furthermore, thermogravimetric analysis (TGA) in air and binder burnout studies of different unlaminated stacking heights and different heating rates were performed.

The complex permeability values are the key parameters that determine properties of ferrite components. These parameters are very dependent on material structural properties and composition. This paper presents comparison of magnetic and structural properties of commercially available LTCC materials ESL 40011 and ESL 40012. The characterization sample, for each material, is a stack of LTCC tapes forming a toroidal shape structure sintered at peak temperatures of 885 °C. For both samples, scanning with electronic microscope was performed in order to determine differences in grain size and porosity. Energy-dispersive spectroscopy (EDS) was used for the elemental analysis of the samples. Obtained EDS spectrum for each samples are compared and analyzed. Permeability, for both materials are determined in the frequency range from 10 kHz to 1 GHz. Measurement procedures are divided in two segments - for low and high frequencies. For low frequency measurements method (from 10 kHz to 1000 kHz) with discrete turns of wire is performed using LCZ meter. On higher frequency range (from 1000 kHz to 1 GHz) method with short coaxial sample holder and Vector Network Analyzer is used. Obtained characteristics for complex permeability are presented and analyzed. It was determine that ESL 40011 has lower value for complex permeability but higher frequency range than ESL 40012. LTCC material ESL 40011 have maximal value 263 for real part of complex permeability at 2.3 MHz and ESL 40012 have maximal value 678 for real part of complex permeability at 0.5 MHz. Additionally, dispersion parameters of analyzed feritic materials are determined and compared.

Low temperature co-fired ceramic (LTCC) technology allows to create 3-D ceramic devices from tapes with different electrical and magnetic properties. Recently ferrimagnetic materials became available as LTCC tapes. To magnetically characterise the ferritic LTCC material we have realised ring samples using ESL 40012 LTCC-tapes. The ring core fabrication process and the sample preparation are described in detail. The quasi-static B(H) curve has been measured by inductive methods, and its dependence on temperature between room temperature and the Curie temperature is shown.

This paper provides new material property measurement results of the ceramic film material CERAMTAPE GC (manufactured by CERAMTEC GMBH), a commercially available LTCC (Low Temperature Co-fired Ceramics) tape for electronic and microfluidic applications in harsh environment. Following material properties are presented: x-y-z-shrinkage dependent on the lamination pressure, density, weight loss, surface parameters of the green and co-fired tape, thermal properties, Young's modulus, permittivity, chemical composition, and bio-compatibility.

This paper deals with material characterization of ferrite LTCC (Low Temperature Co-fired Ceramic) and influence of ambient temperature variation to its complex permeability value. Results of the material characterization (chemical analysis, surface roughness) of commercially available ESL 40011 ferrite tape are presented for the first time. In addition, complex permeability dependence on frequency is determined using previously verified measurement method and developed dispersion model. Complex permeability dependence on ambient temperature variation is also measured in the frequency range up to 1 GHz. Presented results show decrease of complex permeability maximum value with temperature increase from 20°C to 120°C. Cut-back of the useful frequency range of the material is also noticeable in the same temperature range.

In this paper we propose a method for the synthesis of silver and metal nanoparticles in general. It is based on the reduction of metallic salts dissolved in water by means of non-energetic ions delivered from atmospheric pressure glow discharge plasma. A high-voltage generator with the ability to provide AC and DC voltage components separately is built for this purpose. Using the dielectric barrier discharge plasma reactor it is possible to get uniform rain of ions with tunable current density to penetrate into the salt solution. A porous dielectric plate is employed in the dielectric barrier discharge configuration. The method is tested for synthesis of silver nanoparticles. Obtained nanoparticles were analyzed on SEM and they exhibit spherical shape and sizes in the range of 25 nm to 100 nm.

The complex permeability of commercially available ferrite LTCC (Low Temperature Cofired Ceramics) tapes in dependence of peak sintering temperature have been measured and calculated in the high-frequency range (300 kHz-1.2 GHz). For the first time this dependence is determine at five peak sintering temperatures up to 1300°C. Permeability values have been calculated from S-parameters measured with a vector network analyzer and a short ended coaxial sample holder into which ferritic LTCC toroids have been placed. The toroids were realized by stacking and laminating 62 layers of green tape and then sintered at peak temperatures of 885°C, 1000° C, 1100°C, 1200°C and 1300°C, respectively. Obtained complex permeability values for these toroidal LTCC samples are presented. The maximum real part of permeability values increase up to 930 (at 1100°C firing peak temperature) and show a shift to lower frequency values. At higher sintering temperatures (1200° C and 1300°C) real part of permeability of ferrite samples starts to decrease with further shifting to lower frequency values. In order to determine variation of grain size caused with increasing of sintering temperature and its influence on material complex permeability, an microscopic inspection of samples was performed. Also, using the model of the complex permeability spectra, dispersion parameters of ferrite LTCC material has been determined for various sintering temperatures.

Channel clogging by particles inside microfluidic LTCC devices for biochemical analytics may lead to critical system pressures especially affecting joints, seals or areas of material transition. Biological contamination by device leaks could become a crucial factor regarding operational safety. Therefore, this hereby presented work deals with technological aspects concerning cavity sealing of microfluidic LTCC- devices. Aluminum oxide cover elements as well as sapphire glasses acting as optical windows for spectroscopic investigations are bonded to microfluidic test modules by different glass solders. Different material combinations are discussed by means of compressive strength experiments. CeramTec GC test samples consisting of four layers with a fired thickness of 1mm and a test area of 33mm2 withstand pressures up to 90bar.

In this paper a brief selection of state-of-the-art thermoelectric materials is described which are used for thermoelectric power generation. A summary of current advances in the field of thermoelectric (TE) materials which are used for TE power generation is presented. Among them, the class of filled skutterudite is very promising and extensively investigated. Skutterudites offer good power conversion efficiencies, with the high temperature side of the generators reaching up to 600 °C. Higher temperatures result in technological challenges related to thermomechanically induced stress. Additional difficulties at high temperatures can arise with respect to the reliability of the electrical contacts between the TE materials and metal connectors. Some contacting metals (e.g. silver) tend to diffuse into the active thermoelectric legs and thus are unsuitable for various high-temperature TE materials. As a first step towards a cascaded TE heat engine two Bi 2 Te 3 based TE generators have been evaluated with respect to the influence of TE-leg contacting approaches by measuring their figure-of-merit. While the elements of one TE generator were attached by means of vapor phase bonding using a tin based solder, the elements of the second generator were attached with a silver filled epoxy adhesive.

The complex permeability values of commercially available ferrite LTCC tapes (Low Temperature Cofired Ceramics) in dependence on firing peak temperature have been for the first time determined in the high-frequency range (300 kHz - 1 GHz). Grain size growth due to higher firing peak temperature is compared to the change of the complex permeability. Permeability values have been calculated from S-parameters measured with a vector network analyzer and a short coaxial sample holder into which ferritic LTCC toroids have been placed. The toroids were realized by stacking and laminating 62 layers of green tape and then sintered at peak temperatures of 885 degrees C, 1000 degrees C and 1100 degrees C, respectively. The maximum relative permeability values increase up to 900 (at 1100 degrees C firing peak temperature) and show a shift to lower frequency values.

For the design of a force sensor in low temperature co-fired ceramics (LTCC) technology, the modulus of elasticity of the underlying LTCC substrate is an essential design parameter. Since the LTCC substrate may be subjected to forces that could exceed the flexural strength of a single LTCC layer, multiple LTCC tapes are laminated together in order to increase the maximum applicable force. Preceding measurements did show that the effective modulus of elasticity of LTCC laminates is below the modulus of elasticity of a single LTCC layer with theoretically the same thickness. This paper deals with an analytical model to describe macroscopically the mechanical interface behavior of two-layer LTCC laminates. In this model an interlayer slip is defined which allows the description of the laminate's characteristics by a constant interlayer slip modulus.

Complex magnetic permeability and hysteresis characteristic are key parameters that determine properties of ferrite components. This paper offers effective, accurate and simple method for complex permeability determination of LTCC (Low Temperature Co-fired Ceramic) ferrite sample at wide frequency range (up to 1 GHz). Presented research can be found to be of importance in fields of ferrite components design and application, as well as RF and microwave engineering. The characterization sample is a stack of LTCC tapes forming a toroidal shape structure. Commercially available ferrite tape ESL 40012 was used and standard LTCC processing applied for the sample fabrication. Permeability is determined in the frequency range from 10 kHz to 1 GHz and characterization procedure is divided in two segments - for low and high frequencies. Low frequency measurements (from 10 kHz to 1000 kHz) are performed using LCZ meter and discrete turns of wire, while a short coaxial sample holder and Vector Network Analyzer were used for the higher frequency range (from 1000 kHz to 1 GHz). Hysteresis properties of this material are also determined. B-H hysteresis loops were measured with BROCKHAUS Tester MPG 100D system using the maximum excitation of 2 kA/m and frequencies of 50 Hz, 500 Hz and 1000 Hz. In addition, we presented another important factor in the practical design, the temperature variation of the permeability dispersion parameters. Obtained results show good agreement with datasheet values given by the manufacturer at lower frequencies and are in good correlation with results extracted from developed dispersion model at higher frequencies.

This paper offers an effective, accurate, and simple method for permittivity and permeability determination of an LTCC (low temperature cofired ceramic) ferrite sample. The presented research can be of importance in the fields of ferrite component design and application, as well as for RF and microwave engineering. The characterization sample is a stack of LTCC tapes forming a toroid. Commercially available ferrite tape ESL 40012 was used and standard LTCC processing was applied for the sample fabrication. For the first time, the electrical properties of a ferrite toroid sample of ESL 40012 LTCC ferrite tape is presented at various frequencies. The electrical properties of LTCC ferrite materials, permittivity and specific resistivity, are shown in a frequency range from 10 kHz to 1 MHz using the capacitive method. The hysteresis properties of this material are also determined. B-H hysteresis loops were measured applying a maximum excitation of 2 kA/m and frequencies of 50 Hz, 500 Hz, and 1000 Hz. Permeability is determined in the frequency range from 10 kHz to 1 GHz and a characterization procedure is divided in two segments, for low and high frequencies. Low frequency measurements (from 10 kHz to 1 MHz) are performed using LCZ meter and discrete turns of wire, while a short coaxial sample holder and vector network analyzer were used for the higher frequency range (from 300 kHz to 1 GHz). In addition, another important factor required for the practical design of devices is presented, the temperature variation of the permeability dispersion parameters.

Analysegerat mit einer Probenbehaltereinheit (1) aus einem Probenbehalter zur Aufnahme einer im Wesentlichen flussigen Probe und Markierung der in der Probe enthaltenen Partikel, mit einem Deckel zum flussigkeitsdichten Verschliesen des Probenbehalters; einer Messzelleneinheit (4), welche mit dem Probenbehalter uber einen Abfluss in Fluidverbindung steht, welche Messzelleneinheit einen flussigkeitsleitenden Kanal aufweist, wobei mindestens eine Kanalwand zumindest teilweise transparent ausgebildet ist; einer Tragereinheit (10), welche Mittel zum kontaktlosen Transport und/oder Aufkonzentrierung von in der Probenflussigkeit enthaltenen markierten Partikeln aufweist; sowie mit einer optischen Einheit (20) zur spektroskopischen und/oder mikroskopischen Erfassung der markierten Partikel, mit mindestens einer Lichtquelle (19, 21) zum Anregen der markierten Partikel in der Probe.

A 3-dimensional mesofluidic biological monitoring module has been successfully designed and fabricated using a low-temperature co-fired ceramic (LTCC) technology. This mesofluidic device consists of a network of micro-channels, a spherical mixing cavity and measuring ports. A selection of appropriate commercially available ceramic tapes has been chosen with regard to their biocompatibility performance. Specific processing procedures required for the realization of such a complex structure are demonstrated. Three dimensional numerical flow simulations have been conducted to characterize the concentration profiles of liquids at a specific measuring port and verified by experiment.

This paper presents modeling of the complex permeability spectra, fabrication and a wide frequency range characterization of a toroidal LTCC ferrite sample. A commercial ferrite tape ESL 40012 is used, and standard LTCC (Low Temperature Co-flred Ceramic) processing has been applied to the sample fabrication. The characterization was performed using a short coaxial sample holder and a vector network analyzer in the frequency range from 300kHz to 1GHz, at difierent temperatures. Using the model of the complex permeability spectra dispersion parameters of ferrite LTCC material has been determined for various temperatures. Characteristics of test samples are compared with modeled results and commercially available toroid made of similar NiZn ferrite material.

A 3-dimensional mesofluidic biological monitoring module has been successfully designed and fabricated using a low-temperature co-fired-ceramic (LTCC) technology. This mesofluidic device consists of a network of micro-channels and a spherical mixing cavity. The selection of appropriate commercially available ceramic tapes has been done with regard to their biocompatibility performance. Specific processing procedures required for the realization of such complex structure are demonstrated. Three dimensional numerical flow simulations have been conducted to characterize the concentration profiles of liquids at a specific measuring port and verified by experiment. The module was successfully applied to study complex chemical reaction kinetics complemented by mathematical modelling.

Fluid control is a critical task in chemical processing. For integrated biological monitoring modules with chemical reactors the integration of micropumps is needed. In this paper we report first experiences with a DC-motor driven microfluidic pump fabricated using LTCC technology (low temperature cofired ceramic). The ceramic tapes carrying the required channel and hole structures were laser micromachined. The device contains plugs and pistons formed of ferrofluid, which were actuated by external magnets. The ferrofluid used for this application is a colloidal suspension of ferromagnetic particles in a hydrocarbon carrier fluid which is immiscible in water. On the basis of the first results and driven by the requirement to further decrease the device dimensions, an approach for electromagnetic actuation in LTCC technology has been studied. In order to achieve a magnetic excitation strong enough to drive the micropump, a high ampacity of the microcoils is one key requirement. Inductors with different tape setups including ferritic LTCC tapes and special conductor geometry were considered. An essential and new approach to achieve a large conductor cross section to suit the geometry constraints in the plane direction was carried out by machining channels into the tapes using an Nd: YAG laser and filling them with conductor paste. In this way, coil conductors with 100 μm × 75 μm cross section were successfully fabricated. Magnetic field simulations of two different multilayer arrangements—ferritic (Heraeus AHT03-003 and ESL 40011) and nonferritic tapes—were compared and ampacity measurements up to 3.5 A were performed successfully.