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Abstract: We propose an SMD (surface mount device) sensor in LTCC (low-temperature co-fired ceramic) technology specially designed for standard industrial compressed air. It combines the measurement of pressure, flow, and temperature, with its integrated signal conditioning electronics. Such a sensor can be mounted on an integrated electro-fluidic platform like a standard component using surface mount technology, obviating the need for both wires and tubes. Usually, fluidic sensors in LTCC are dedicated to one physical quantity and need external electronics. The device proposed is the fusion of two independent sensors developed previously: one measuring pressure, the other one measuring flow and temperature. [Copyright &y& Elsevier]

Abstract: We have designed and fabricated a low-range (ca. 100 mN) thick-film piezoresistive force sensor with a cantilever beam fabricated in LTCC (Low Temperature Co-fired Ceramic). The beam was soldered onto a standard thick-film 25.4 x 12.7 mm signal conditioning base [1]. Switching from a classical Al2O3-based thick-film beam to LTCC allows design of a 3D structured beam with increased sensitivity of the piezoresistive bridge, yet largely conserved strength and stiffness. Another advantage of LTCC compared to alumina is a lower Young’s modulus (approx. 3 times lower), more suitable for the measurement of small loads. [Copyright &y& Elsevier]

Ease of fabrication and design flexibility are two attractive features of low-temperature co-fired ceramics (LTCC) technology for fabrication of complex micro-fluidic devices. Such structures are designed and processed using different shaping methods, the extent and complexity of which depends on the final device specifications (dimensions, and mechanical and functional properties). In this work, we propose a sacrificial layer method based on carbon-black paste, which burns out during the LTCC firing stage. The article will summarize the preparation of the paste, influence of processing conditions on the final dimensions, and demonstrate the mechanically integrated structures obtained using this technique. Some of these are membranes of various diameters (7–12 mm) with a thickness of 40 μm and a variety of internal spacing (15–60 μm), free-hanging thick-film resistor bridges on LTCC for heating micro-volumes. The main methods of the study will be thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and dilatometry in addition to electronic instruments for device characterization. [ABSTRACT FROM AUTHOR]

• LTCC-3D high-frequency magnetic sensors manufactured in-house, operational on TCV. • Measurements of perturbation to the parallel, poloidal, radial field components. • Frequency range of the measurements: from 1 kHz to 1 MHz. • LTCC-3D and Mirnov data for δBPOL agree in common frequency range of measurements. • Data on δBPOL up to 1 MHz, on δBPAR and δBRAD components, not previously available. Innovative 3D high-frequency magnetic sensors have been designed and manufactured in-house for installation on the Tokamak à Configuration Variable (TCV), and are currently routinely operational. These sensors combine the Low Temperature Co-fired Ceramic (LTCC) and the thick-film technologies, and are in various aspects similar to the majority of the inductive magnetic sensors currently being procured for ITER (290 out of 505 are LTCC-1D). The TCV LTCC-3D magnetic sensors provide measurements in the frequency range up to 1MHz of the perturbations to the toroidal (quasi-parallel: δB TOR ˜δB PAR), vertical (quasi-poloidal: δB VER ˜δB POL), and radial (δB RAD) magnetic field components, the latter being generally different from the component normal to the Last Closed Flux-Surface (δB NOR). The LTCC-3D δB RAD measurements improve significantly on the corresponding data with the saddle loops, which are mounted onto the wall and have a bandwidth of ˜3 kHz (due to the wall penetration time). The LTCC-3D δB TOR measurements (not previously available in TCV) provide evidence that certain MHD modes have a finite δB PAR at the LCFS, as recently calculated for pressure-driven instabilities. The LTCC-3D δB POL measurements allow to cross-check the data obtained with the Mirnov coils, and led to the identification of large EM noise pick-up for the Mirnov DAQ. The LTCC-3D data for δB POL agree with those obtained with the Mirnov sensors in the frequency range where the respective data acquisition overlap, routinely up to 125kHz, and up to 250kHz in some discharges, when the EM noise pick-up on the Mirnov DAQ is removed. Finally, we look at what lessons can be learnt from our work for the forthcoming procurement, installation and operation of the LTCC-1D sensors in ITER. [ABSTRACT FROM AUTHOR]

Abstract: This paper is an overview of work carried out on the design of the ITER high-frequency magnetic diagnostic coil (HF sensor). In the first part, the ITER requirements for the HF sensor are presented. In the second part, the ITER reference design of the HF sensor has been assessed and showed some potential weaknesses, which led us to the conclusion that alternative designs could usefully be examined. Several options have been explored, and are presented in the third part: (a) direct laser cutting a metallic tube, (b) stacking of plane windings manufactured from a tungsten plate by electrical discharge machining, (c) coil using the conventional spring manufacture. In the fourth part, sensors using the low temperature co-fired ceramic technology (LTCC) are presented: (d) monolithic 1D magnetic flux sensors based on LTCC technology, and (e) monolithic 3D magnetic flux sensors based on the same LTCC technology. The solution which showed the best results is the monolithic 3D magnetic flux sensor based on LTCC. [Copyright &y& Elsevier]