Search results for "electronics"

Microwave properties and structure of La–Ti–Si–B–O glass-ceramics for applications in GHz electronics

2017

Abstract A dielectric bulk glass-ceramic of the La 2 O 3 –TiO 2 –SiO 2 –B 2 O 3 system is developed which is able to fulfill the requirements for dielectric loading-based mobile communication technologies. It is shown that the given dielectric requirements can be fulfilled by glass-ceramic materials without being dependent on ceramic processing techniques. The material exhibited permittivity values of 20  ɛ r Qf τ f τ f material with a Qf value of 9500 GHz and ɛ r  = 21.4 could be achieved at a ceramming temperature T cer  = 870 °C. The material is aimed to provide an alternative to existing, commercially used sintered ceramic materials. Further focus is laid on the investigation of the dom…

Investigation of ZrO[sub 2]–Gd[sub 2]O[sub 3] Based High-k Materials as Capacitor Dielectrics

2010

Atomic layer deposition (ALD) of ZrO 2 ―Gd 2 O 3 nanolaminates and mixtures was investigated for the preparation of a high permittivity dielectric material. Variation in the relative number of ALD cycles for constituent oxides allowed one to obtain films with controlled composition. Pure ZrO 2 films possessed monoclinic and higher permittivity cubic or tetragonal phases, whereas the inclusion of Gd 2 O 3 resulted in the disappearance of the monoclinic phase. Changes in phase composition were accompanied with increased permittivity of mixtures and laminates with low Gd content. Further increase in the lower permittivity Gd 2 O 3 content above 3.4 cat. % resulted in the decreased permittivity…

Mixed-Mode Operation of Hybrid Phase-Change Nanophotonic Circuits

2016

Phase change materials (PCMs) are highly attractive for nonvolatile electrical and all-optical memory applications because of unique features such as ultrafast and reversible phase transitions, long-term endurance, and high scalability to nanoscale dimensions. Understanding their transient characteristics upon phase transition in both the electrical and the optical domains is essential for using PCMs in future multifunctional optoelectronic circuits. Here, we use a PCM nanowire embedded into a nanophotonic circuit to study switching dynamics in mixed-mode operation. Evanescent coupling between light traveling along waveguides and a phase-change nanowire enables reversible phase transition b…

Luminescence dynamics of hybrid ZnO nanowire/CdSe quantum dot structures

2016

Colloidal CdSe quantum dots (QDs) functionalized with different organic linker molecules are attached to ZnO nanowires (NWs) to investigate the electron transfer dynamics between dots and wires. After linking the quantum dots to the nanowires, the photo-induced electron transfer (PET) from the QDs into the NWs becomes visible in the PL transients by a decrease of dot luminescence decay time. The different recombination paths inside the QDs and the PET process are discussed in the framework of a rate equation model. Photoconductivity studies confirm the electron transfer by demonstrating a strong enhancement of the wire photocurrent under light irradiation into the dot transition. (© 2016 WI…

Defect-related photoluminescence and photoluminescence excitation as a method to study the excitonic bandgap of AlN epitaxial layers: Experimental an…

2020

We report defect-related photoluminescence (PL) and its vacuum ultraviolet photoluminescence excitation (PLE) spectra of aluminum nitride layers with various layer thicknesses and dislocation densities grown on two different substrates: sapphire and silicon. The defect-related transitions have been distinguished and examined in the emission and excitation spectra investigated under synchrotron radiation. The broad PL bands of two defect levels in the AlN were detected at around 3 eV and 4 eV. In the PLE spectra of these bands, a sharp excitonic peak originating most probably from the A-exciton of AlN was clearly visible. Taking into account the exciton binding energy, the measurements allow…

Photoluminescence in Er-doped 0.4Na1/2Bi1/2TiO3-(0.6-x)SrTiO3-xPbTiO3 solid solutions

2020

Photoluminescence and optical second harmonic generation in Er-doped 0.4Na0.5Bi0.5TiO3-(0.6-x)SrTiO3-xPbTiO3 solid solutions is studied. Earlier, it was shown that upon increasing of PbTiO3 concent...

2021

Atomic layer deposition (ALD) technology has unlocked new ways of manipulating the growth of inorganic materials. The fine control at the atomic level allowed by ALD technology creates the perfect conditions for the inclusion of new cationic or anionic elements of the already-known materials. Consequently, novel material characteristics may arise with new functions for applications. This is especially relevant for inorganic luminescent materials where slight changes in the vicinity of the luminescent centers may originate new emission properties. Here, we studied the luminescent properties of CaS:Eu by introducing europium with oxygen ions by ALD, resulting in a novel CaS:EuO thin film. We …

Enhancement of the Multipactor Threshold Inside Nonrectangular Iris

2018

Multipactor breakdown is studied inside the capacitive iris of a rectangular waveguide with a skewed slot along its longitudinal cross section. Both the iris length and height are assumed to be small compared to the electromagnetic wavelength. Therefore, the quasi-static approximation is applied so as to describe the RF field distribution inside the iris gap, whereas a 2-D model is used to analyze the electron motion. The peculiarities of RF field structure are studied using the conformal mapping approach, which shows that the electric field lines can be approximated by circular arcs when the iris length is much larger than its height. The electron motion inside the iris gap is analyzed usi…

Radiation hardness studies of CdTe and for the SIXS particle detector on-board the BepiColombo spacecraft

2009

Abstract We report of the radiation hardness measurements that were performed in the developing work of a particle detector on-board ESA's forthcoming BepiColombo spacecraft. Two different high- Z semiconductor compounds, cadmium telluride (CdTe) and mercuric iodide (HgI 2 ), were irradiated with 22 MeV protons in four steps to attain the estimated total dose of 10 12 p / cm 2 for the mission time. The performance of the detectors was studied before and after every irradiation with radioactive 55 Fe source Mn K α 5.9 keV emission line. We studied the impact of the proton beam exposure on detector leakage current, energy resolution and charge collection efficiency (CCE). Also the reconstruct…

Risk Assessment of Electron Induced SEE during the JUICE Mission

2018

The SEE sensitivity of electronic devices to high energy electrons has been put in evidence experimentally. Several ground experiments have shown that electron induced SEE could occur in recent technologies. In the case of the JUICE mission, the expected electron environment is harsher than for Earth orbits. The impact of such electron fluxes on the embedded electronics was assessed in this work. The study focused on SRAM memories SEU sensitivity. Three different device references were tested under electrons, as well as under protons and heavy ions. The electron and the low energy proton direct ionization contributions to the total SEU rate have been studied in more detail.