Epitaxially grown electrodes for high-temperature stable piezoelectric transducers are prepared by pulsed laser depostion. To adjust the stoichiometry in the films, oxygen partial pressure, target composition and deposition temperature are varied. Langasite films with enhanced conductivity are deposited, serving as electrodes for nearly monolithic piezoelectric resonators. These resonators show strong admittance maxima for their 1st, 3rd and 5th harmonics and are not affected by spurious modes.

Thin tantalum films generated by glancing angle deposition serve as functional optical layers. Serial sectioning by a focused ion beam combined with scanning electron microscopy of the slices generates stacks of highly resolved images of this film. Dedicated image processing reconstructs the spatial structure such that 3-D image analysis yields geometric information that can be related to the optical performance.

High-performance relative humidity (RH) sensing system using poly(3,4-ethylenedioxythiophene) and polystyrene sulfonate mixed with polyvinyl alcohol (PEDOT–PSS/PVA) nanofiber coated on top of a quartz crystal microbalance (QCM) chip is developed. Results show that the sensor offers easy fabrication processes and provides excellent sensor characteristics to relative humidity sensing. It offers a very promising alternative method to fabricate high-performance relative humidity sensors.

This article discusses the properties of different diamagnetic and paramagnetic materials for a basic current/magnetic field sensor system set up with different relative orientations of analyzers and polarizers. The paper analyzes a linearity range of different materials and their sensitivity for different wavelengths. Terbium doped glass, terbium gallium garnet, doped TGG and dense flint glass materials are used for analysis based on the Faraday rotation principle.

Current additive manufacturing allows for the implementation of electrically integrated 3-D printed sensors. In this contribution various technologies, sensing principles and applications are discussed. We will give both an overview of some of the sensors presented in literature as well as some of our own work on recent 3-D printed sensors.

This research is about future sensor devices for force, pressure, and weight. The core of such sensors for mechanical quantities is a thin film that reacts to deformation. We are developing new sensor films with higher output. Different compositions of metal containing carbon films are examined. Most preferable and stable films contain nickel and carbon. The microscopic film morphology is uncovered. Electron tunneling between nanoparticles is responsible for the very sensitive reaction.

Indium oxide inverse opal is a promising new material for optical gas sensors. The photonic properties caused by the inverse opal structure can be utilized to read out the sensors’ electronical state by optical methods. The maintenance of good thermal stability of transducer material during operation is a minimum requirement. We present results on the synthesis and investigation of the structural stability of the In₂O₃ inverse opal structure up to a temperature of 550 °C (limit of substrate).

This paper investigates the effect of high-temperature and low-temperature (< 150 °C) processing conditions on the surface composition of the substrate. Furthermore, the resultant transducers from high- and low-temperature fabrication processes are compared to determine if a low-temperature processing method is feasible. For these studies a sol-gel spray-on process is employed to deposit piezoelectric ceramics onto a stainless-steel 316L substrate.

The effect of stored ammonia on the complex dielectric permittivity of H-ZSM-5 zeolites with varying storage site density was observed between 200 and 300 °C under reaction conditions by microwave cavity perturbation. Polarization and dielectric losses were differently affected. The sensitivity of the polarization to stored ammonia is almost independent, the sensitivity of the dielectric losses strongly dependent on the storage site density. The results can be explained by proton hopping.

In this paper we show that for radially symmetric piezoceramic disks non-zero sensitivity of the electrical impedance to the whole material parameter set can be computed using a system of 3-ring electrodes and non-uniform electrical excitation. We formulate an optimisation problem for increasing this sensitivity. However, the system displays multiple optimal configurations for the radii of said ring electrodes and we have shown some results from optimising such configurations using simulations.

We report on the high-temperature piezoresistivity of carbon-containing silicon oxycarbide nanocomposites (C/SiOC). The piezoresistive behavior of the C/SiOC nanocomposites relies on the presence of dispersed nanocrystalline graphite and non-crystalline carbon domains. In comparison to highly ordered carbon, C/SiOC exhibits strongly enhanced sensitivities, even at high temperatures. Thus, k values of ca. 80 at the highest temperature reading, 1200°C, reveal that C/SiOC is a primary candidate.

Electrochemically synthesized colloidal Au NPs with controlled dimension and composition were successfully deposited electrophoretically on CNT networked films. Au NP/CNT films were tested as active layers in resistive NO2 sensors, exhibiting a p-type response and a sensitivity depending on Au loading. The impact of the Au loading on gas sensing performance was investigated as a function of the working temperature, gas concentration and interfering gases.