Non-stoichiometric hydrogenated amorphous silicon nitride (a-SiNx : H) film was deposited by helico-wave plasma-enhanced chemical vapour deposition (HWP-CVD) technique. The microstructure and bonding characteristics of both as-deposited and annealed thin films were studied. Raman scattering measurement shows that excess silicon exists in the form of amorphous silicon particles in the as-deposited sample. The microstructure of crystalline nano-particles silicon embedded in silicon nitride matrix in the post-annealed sample was formed. Comparing the results of both the Fourier transform infrared spectra and the optical absorption spectra of the samples deposited under different conditions, it is shown that the microstructure of the thin film depended on the gas flow ratio and annealing process. The sample with lower excess silicon shows a lower density of defect state at the silicon nanocrystal/SiNx interface due to a higher binding hydrogen content. The annealing process induces the decrease in Si-H and N--H binding densities. Because of the formation of silicon nanocrystals, the annealed samples exhibit a higher structure disorder degree.
Download full-text PDF |
Source |
---|
Sci Rep
January 2025
Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA.
The aberrant vascular response associated with tendon injury results in circulating immune cell infiltration and a chronic inflammatory feedback loop leading to poor healing outcomes. Studying this dysregulated tendon repair response in human pathophysiology has been historically challenging due to the reliance on animal models. To address this, our group developed the human tendon-on-a-chip (hToC) to model cellular interactions in the injured tendon microenvironment; however, this model lacked the key element of physiological flow in the vascular compartment.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
January 2025
School of Materials Science and Engineering, University of Jinan, Jinan, 250022, China. Electronic address:
Silicon nitride (Si₃N₄) ceramics exhibit excellent mechanical properties and biocompatibility, making them highly suitable for biomedical applications, particularly in implants. In this study, the mechanical properties and bioactivity of Si₃N₄ ceramics with varying amounts of Y₂O₃-Al₂O₃-SiO₂ sintering aids were investigated. Increasing the sintering additive content from 4 wt% to 8 wt% substantially improved the bulk density of the ceramics, leading to notable enhancements in mechanical properties.
View Article and Find Full Text PDFBiosensors (Basel)
January 2025
INFN-Laboratori Nazionali di Frascati, Via E. Fermi 54, 00044 Frascati, Italy.
The COVID-19 pandemic has highlighted the urgent need for rapid, sensitive, and reliable diagnostic tools for detecting SARS-CoV-2. In this study, we developed and optimized a surface plasmon resonance (SPR) biosensor incorporating advanced materials to enhance its sensitivity and specificity. Key parameters, including the thickness of the silver layer, silicon nitride dielectric layer, molybdenum disulfide (MoS) layers, and ssDNA recognition layer, were systematically optimized to achieve the best balance between sensitivity, resolution, and attenuation.
View Article and Find Full Text PDFRSC Chem Biol
January 2025
Department of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine Kamigyo-ku 465 Kajii-cho Kyoto 602-8566 Japan
A multiomic study of the structural characteristics of type A and B influenza viruses by means of highly spectrally resolved Raman spectroscopy is presented. Three virus strains, A H1N1, A H3N2, and B98, were selected because of their known structural variety and because they have co-circulated with variable relative prevalence within the human population since the re-emergence of the H1N1 subtype in 1977. Raman signatures of protein side chains tyrosine, tryptophan, and histidine revealed unequivocal and consistent differences for pH characteristics at the virion surface, while different conformations of two C-S bond configurations in and methionine rotamers provided distinct low-wavenumber fingerprints for different virus lineages/subtypes.
View Article and Find Full Text PDFDiscov Nano
January 2025
LIMMS, CNRS-IIS IRL 2820, The University of Tokyo, Tokyo, 153-8505, Japan.
We demonstrate unprecedented control and enhancement of thermal radiation using subwavelength conical membranes of silicon nitride. Based on fluctuational electrodynamics, we find that the focusing of surface phonon-polaritons along these membranes enhances their far-field thermal conductance by three orders of magnitude over the blackbody limit. Our calculations reveal a non-monotonic dependence of the thermal conductance on membrane geometry, with a characteristic radiation plateau emerging at small front widths due to competing effects of the polariton focusing and radiative area.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!