Smart sensors are needed to achieve a more intelligent aero-engine. The thin-film sensor array is thereby fabricated on the turbine blade surface using MEMS technology to measure the surface temperature distribution for the first time. A series of PtRh/Pt thin film thermocouple (TFTC) is directly integrated in-situ on blade surface by dry film photolithography and magnetron sputtering technology. A series of high temperature experiments are performed to test its annealing effect, stability and repeatability, responsiveness, and temperature distribution. The experimental results show that after annealing at 800 °C for 1 hour, TFTCs exhibit good stability and consistency. This TFTC array can capture the temperature distribution caused by the heat flame on the blade surface, and the transient temperature responsiveness can reach at least 10 μs under a dynamic heat flow. The TFTC is only 1 μm thick thin film coated on the blade surface and the thin film routing can direct the joint connection to the edge of the blade, hence causing minimum surface heat flow patterns and structure modulation. Therefore such TFTC array is very useful for accurate transient temperature measurements such as on turbine blade surface, comparing to the wired thermocouple method.

High temperature measurement of the rotating parts in aero-engine system requires wireless passive sensors. Surface acoustic wave (SAW) devices capable of measuring high temperature wirelessly are therefore ideal for these extreme scenarios where wired sensors are not applicable. In this article, SAW sensors built on the LiNbO ₃ substrate which can measure up to 1100 °C with a good repeatability and endurance are reported. The platinum IDT and LiNbO ₃ substrate were effectively protected by a SiO ₂ passivation layer to ensure the functionality and stability of the SAW devices under extremely high temperature. Distinct linearity of f ₀ vs. temperature, together with the temperature durability of the SAW sensors were verified by conducting various high-temperature RF tests. Such a SAW sensor attached with an embedded near-field antenna was also formulated to enhance the wireless transmission quality for future high-temperature remote sensing system.

A new quasi-Coulomb relation between magnetic force vs distance, magnetic flux density, and magnetic pole area is proposed in this paper based on the empirical analysis on the magnetic force vs distance measurements. A simple device is designed and fabricated to measure the repulsive/attractive magnetic force between two magnets. The measurement results show that the relationship between the magnetic force and distance is similar to Coulomb’s electrostatic law, but the attraction is greater than the repulsion. The magnetic force is proportional to the integral of the magnetic flux density with the areas of the magnetic pole. This quasi-Coulomb relationship is useful to evaluate the torque and speed of a rim-driven motor, which plays an important role in electrified propulsion in green aviation technology.

Summary form only given. In SOI MOSFETs, the holes (for n-channel devices) generated by impact ionization near the drain can not be properly removed as in the case of bulk MOSFETs. Due to the confinement by the buried oxide inherent in a SOI structure, the holes generated through impact ionization redistribute in the floating body and enhance the impact ionization rate near the edges of the channel, increasing with increasing device width. This is experimentally evidenced by the measured lower single transistor latch on voltages and higher linear current degradation in typical fully depleted (FD) SOI MOSFETs, and a stronger kink effect in typical partially-depleted (PD) MOSFETs, as the device width increases. It is thus suggested that more attention should be paid to the edges of the device during design and fabrication, to decrease impact ionization and/or increase carrier recombination locally. Also, in contrast to bulk technology, circuit designers must be aware that devices of different widths may have different latch-up voltages and that the hot carrier device lifetime might be underestimated if the narrow devices are tested.