In this work, we present a method for growing highly -axis oriented aluminum scandium nitride (AlScN) thin films on (100) silicon (Si), silicon dioxide (SiO) and epitaxial polysilicon (poly-Si) substrates using a substrate independent approach. The presented method offers great advantages in applications such as piezoelectric thin-film-based surface acoustic wave devices where a metallic seed layer cannot be used. The approach relies on a thin AlN layer to establish a wurtzite nucleation layer for the growth of -AlScN films.
View Article and Find Full Text PDFIn this work, the first surface acoustic-wave-based magnetic field sensor using thin-film AlScN as piezoelectric material deposited on a silicon substrate is presented. The fabrication is based on standard semiconductor technology. The acoustically active area consists of an AlScN layer that can be excited with interdigital transducers, a smoothing SiO layer, and a magnetostrictive FeCoSiB film.
View Article and Find Full Text PDFIEEE Trans Biomed Circuits Syst
October 2020
Magnetomyography (MMG) with superconducting quantum interference devices (SQUIDs) enabled the measurement of very weak magnetic fields (femto to pico Tesla) generated from the human skeletal muscles during contraction. However, SQUIDs are bulky, costly, and require working in a temperature-controlled environment, limiting wide-spread clinical use. We introduce a low-profile magnetoelectric (ME) sensor with analog frontend circuitry that has sensitivity to measure pico-Tesla MMG signals at room temperature.
View Article and Find Full Text PDFA novel Ge-As-Se-Te chalcogenide glass (ChG)-tapered fiber (ChG-TF) sensor for detecting environmentally relevant organic pollutants with p-xylene as the model was investigated. The prominent design feature of the sensor is that its tapered zone was coated with a polydopamine membrane by a facile in situ self-polymerization process. As the tapered zone exposed to the aqueous sample, the p-xylene molecules would be enriched into the polydopamine coating.
View Article and Find Full Text PDFWe demonstrated an ultrabroadband supercontinuum (SC) generation with high coherence property in all-normal-dispersion (ANDi) Te-based chalcogenide tapered fiber. The fibers made of GeAsSeTe core and GeAsSeTe cladding glasses were fabricated via isolated stacked extrusion. The waist diameter and length can be accurately controlled by a homemade tapering platform.
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