33 results match your criteria: "Fraunhofer Institute for Organic Electronics[Affiliation]"

Group III-nitride semiconductors have been subject of intensive research, resulting in the maturing of the material system and adoption of III-nitrides in modern optoelectronics and power electronic devices. Defined film polarity is an important aspect of III-nitride epitaxy as the polarity affects the design of electronic devices. Magnetron sputtering is a novel approach for cost-effective epitaxy of III-nitrides nearing the technological maturity needed for device production; therefore, control of film polarity is an important technological milestone.

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The respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infections associated with numerous hospitalizations. Recently, intramuscular (i.m.

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Tuning Surface Defect States in Sputtered Titanium Oxide Electron Transport Layers for Enhanced Stability of Organic Photovoltaics.

ACS Appl Mater Interfaces

April 2024

Mads Clausen Institute, Center for Advanced Photovoltaics and Thin Film Energy Devices (SDU CAPE), University of Southern Denmark, So̷nderborg 6400, Denmark.

Article Synopsis
  • * Recent studies indicate that the photocatalytic breakdown of NFA molecules at metal oxide electron transport layer (ETL) interfaces is a key factor in device degradation.
  • * This research shows that using sputtered titanium oxide layers as ETLs can notably improve the longevity of NFA-based OPVs by reducing defect states and photocatalytic degradation, achieving around 10% efficiency and enhanced stability in a scalable manner.
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Respiratory syncytial virus (RSV) is a leading cause of acute lower respiratory tract infections in the elderly and in children, associated with pediatric hospitalizations. Recently, first vaccines have been approved for people over 60 years of age applied by intramuscular injection. However, a vaccination route via mucosal application holds great potential in the protection against respiratory pathogens like RSV.

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Nanoscale Thermometry of Plasmonic Structures via Raman Shifts in Copper Phthalocyanine.

J Phys Chem C Nanomater Interfaces

May 2023

Department of Physics and Astronomy, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands.

Temperature measurements at the nanoscale are vital for the application of plasmonic structures in medical photothermal therapy and materials science but very challenging to realize in practice. In this work, we exploit a combination of surface-enhanced Raman spectroscopy together with the characteristic temperature dependence of the Raman peak maxima observed in β-phase copper phthalocyanine (β-CuPc) to measure the surface temperature of plasmonic gold nanoparticles under laser irradiation. We begin by measuring the temperature-dependent Raman shifts of the three most prominent modes of β-CuPc films coated on an array of Au nanodisks over a temperature range of 100-500 K.

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The enhanced piezoelectric properties of aluminum scandium nitride (AlScN or AlScN) were discovered in 2009 by Morito Akiyama's team [...

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Radiation-attenuated intracellular parasites are promising immunization strategies. The irradiated parasites are able to invade host cells but fail to fully replicate, which allows for the generation of an efficient immune response. Available radiation technologies such as gamma rays require complex shielding constructions and are difficult to be integrated into pharmaceutical production processes.

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Hemocompatibility tuning was adopted to explore and refine an innovative, GA-free preparation strategy combining decellularization, riboflavin/UV crosslinking, and low-energy electron irradiation (SULEEI) procedure. A SULEEI-protocol was established to avoid GA-dependent deterioration that results in insufficient long-term aortic valve bioprosthesis durability. Final SULEEI-pericardium, intermediate steps and GA-fixed reference pericardium were exposed in vitro to fresh human whole blood to elucidate effects of preparation parameters on coagulation and inflammation activation and tissue histology.

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Infrared Spectroscopic Verification of a α-Helical Collagen Structure in Glutaraldehyde-Free Crosslinked Bovine Pericardium for Cardiac Implants.

Life (Basel)

December 2022

Department of Anaesthesiology and Critical Care Medicine, Clinical Sensoring and Monitoring, Faculty of Medicine, Technische Universität Dresden, 01307 Dresden, Germany.

The degeneration of heart valve bioprostheses due to calcification processes is caused by the intercalation of calciumhydroxyapatite in pericardium collagen bundles. Variations of the protein secondary structure of biomaterials according to preparation are relevant for this mineralization process and thus the structural characterization of innovative bioprostheses materials is of great importance. The gold standard for prostheses preparation is glutaraldehyde (GA)-fixation of bovine pericardium that adversely promotes calcification.

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Photoconduction (PC) properties were investigated for ternary indium aluminium nitride (In Al N) nanorods (NRs) with different indium compositions () from 0.35 to 0.68, as grown by direct-current reactive magnetron sputter epitaxy.

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The laser ultrasound (LU) technique has been used to determine dispersion curves for surface acoustic waves (SAW) propagating in AlScN/AlO systems. Polar and non-polar AlScN thin films were prepared by magnetron sputter epitaxy on AlO substrates and coated with a metal layer. SAW dispersion curves have been measured for various propagation directions on the surface.

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This paper reports on the deposition and characterization of piezoelectric AlScN (further: AlScN) films on Si substrates using AlSc alloy targets with 30 at.% Sc. Films were deposited on a Ø200 mm area with deposition rates of 200 nm/min using a reactive magnetron sputtering process with a unipolar-bipolar hybrid pulse mode of FEP.

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Thermal Analysis of Parylene Thin Films for Barrier Layer Applications.

Polymers (Basel)

September 2022

Sitem Center for Translational Medicine and Biomedical Entrepreneurship, University of Bern, Freiburgstrasse 3, 3010 Bern, Switzerland.

Biocompatible polymer films demonstrating excellent thermal stability are highly desirable for high-temperature (>250 °C) applications, especially in the bioelectronic encapsulation domain. Parylene, as an organic thin film, is a well-established polymer material exhibiting excellent barrier properties and is often the material of choice for biomedical applications. This work investigated the thermal impact on the bulk properties of four types of parylene films: parylene N, C, VT4, and AF4.

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Low-energy electron irradiation is an emerging alternative technology for attenuated or complete pathogen inactivation with respect to medical, biotechnological, and pharmaceutical applications. Pathogen inactivation by ionizing radiation depends mainly on the absorbed electron dose. In low-energy electron irradiation processes, determination of the absorbed electron dose is challenging due to the limited, material-dependent penetration depth of the accelerated electrons into the matter.

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Piezoelectric micromirrors with aluminum nitride (AlN) and aluminum scandium nitride (AlScN) are presented and compared regarding their static deflection. Two chip designs with 2 × 3 mm (Design 1) and 4 × 6 mm (Design 2) footprint with 600 nm AlN or 2000 nm AlScN as piezoelectric transducer material are investigated. The chip with Design 1 and AlScN has a resonance frequency of 1.

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Tick-borne encephalitis virus (TBEV) is a zoonotic flavivirus which is endemic in many European and Asian countries. Humans can get infected with TBEV usually ticks, and possible symptoms of the infection range from fever to severe neurological complications such as encephalitis. Vaccines to protect against TBEV-induced disease are widely used and most of them consist of whole viruses, which are inactivated by formaldehyde.

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Influence of Crystal Structure, Encapsulation, and Annealing on Photochromism in Nd Oxyhydride Thin Films.

J Phys Chem C Nanomater Interfaces

February 2022

Materials for Energy Conversion and Storage, Department of Chemical Engineering, Delft University of Technology, Van der Maasweg 9, NL-2629HZ Delft, The Netherlands.

Article Synopsis
  • - Thin films of rare earth metal oxyhydrides exhibit photochromic effects, but the exact mechanism is not yet understood.
  • - By adjusting the composition (O:H) during sputtering, we can alter the films' band gap, crystal structure, and photochromic contrast.
  • - To extend the lifespan of these films from 1 day to several months, we applied a thin ALD coating of AlO, which also affects the bleaching speed and kinetics of the photochromic effect.
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Vaccines consisting of whole inactivated bacteria (bacterins) are generated by incubation of the pathogen with chemicals. This is a time-consuming procedure which may lead to less immunogenic material, as critical antigenic structures can be altered by chemical modification. A promising alternative approach is low-energy electron irradiation (LEEI).

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Brillouin confocal microscopy to determine biomechanical properties of SULEEI-treated bovine pericardium for application in cardiac surgery.

Clin Hemorheol Microcirc

November 2021

Department of Medical Physics and Biomedical Technology, Carl Gustav Carus Faculty of Medicine, Technische Universität Dresden, Dresden, Germany.

Background: Heart valves are exposed to a highly dynamic environment and underlie high tensile and shear forces during opening and closing. Therefore, analysis of mechanical performance of novel heart valve bioprostheses materials, like SULEEI-treated bovine pericardium, is essential and usually carried out by uniaxial tensile tests. Nevertheless, major drawbacks are the unidirectional strain, which does not reflect the in vivo condition and the deformation of the sample material.

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Background: With increasing clinical use of NK-92 cells and their CAR-modified derivatives in cancer immunotherapy, there is a growing demand for efficient production processes of these "off-the-shelf" therapeutics. In order to ensure safety and prevent the occurrence of secondary tumors, (CAR-)NK-92 cell proliferation has to be inactivated before transfusion. This is commonly achieved by gamma irradiation.

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Influence of Cation (RE = Sc, Y, Gd) and O/H Anion Ratio on the Photochromic Properties of REO H Thin Films.

ACS Photonics

March 2021

Materials for Energy Conversion and Storage, Department of Chemical Engineering, Delft University of Technology, Van der Maasweg 9, NL-2629HZ Delft, The Netherlands.

Article Synopsis
  • Rare-earth oxyhydride thin films exhibit a reversible photochromic effect, changing color under ambient conditions when prepared through air-oxidation of REH dihydrides.
  • The extent and speed of the optical change can be controlled by adjusting the O/H anion ratio and selecting different rare-earth cations.
  • Larger ionic radius rare-earth elements result in oxyhydrides with enhanced optical contrast and quicker bleaching times, indicating a correlation between the photochromic mechanism and anion behavior.
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Ionizing radiation is widely used to inactivate pathogens. It mainly acts by destroying nucleic acids but causes less damage to structural components like proteins. It is therefore highly suited for the sterilization of biological samples or the generation of inactivated vaccines.

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Bacterial pathogens cause severe infections worldwide in livestock and in humans, and antibiotic resistance further increases the importance of prophylactic vaccines. Inactivated bacterial vaccines (bacterins) are usually produced via incubation of the pathogen with chemicals such as formaldehyde, which is time consuming and may cause loss of immunogenicity due to the modification of structural components. We evaluated low-energy electron irradiation (LEEI) as an alternative method to generate a bacterin.

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Background:  Bovine pericardium is the major natural source of patches and aortic valve substitutes in cardiac repair procedures. However, long-term tissue durability and biocompatibility issues lead to degeneration (e.g.

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