المؤلفون: Alexandre Heintz, Bouraoui Ilahi, Alexandre Pofelski, Gianluigi Botton, Gilles Patriarche, Andrea Barzaghi, Simon Fafard, Richard Arès, Giovanni Isella, Abderraouf Boucherif

المصدر: Nature Communications, Vol 13, Iss 1, Pp 1-9 (2022)

مصطلحات موضوعية: Science

الوصف: Many complex devices rely on epitaxial growth with high crystallinity and accurate composition. Here authors report epitaxial growth of Ge on deep etched porous Si pillars to provide a fully compliant substrate enabling elastic relaxation of defect free Ge microcrystals.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2041-1723Test

الوصول الحر: https://doaj.org/article/b0302eb751114196bc93e20db9171c4cTest

المؤلفون: Marco Albani, Roberto Bergamaschini, Andrea Barzaghi, Marco Salvalaglio, Joao Valente, Douglas J. Paul, Axel Voigt, Giovanni Isella, Francesco Montalenti

المصدر: Scientific Reports, Vol 11, Iss 1, Pp 1-12 (2021)

مصطلحات موضوعية: Medicine, Science

الوصف: Abstract The development of three-dimensional architectures in semiconductor technology is paving the way to new device concepts for various applications, from quantum computing to single photon avalanche detectors. In most cases, such structures are achievable only under far-from-equilibrium growth conditions. Controlling the shape and morphology of the growing structures, to meet the strict requirements for an application, is far more complex than in close-to-equilibrium cases. The development of predictive simulation tools can be essential to guide the experiments. A versatile phase-field model for kinetic crystal growth is presented and applied to the prototypical case of Ge/Si vertical microcrystals grown on deeply patterned Si substrates. These structures, under development for innovative optoelectronic applications, are characterized by a complex three-dimensional set of facets essentially driven by facet competition. First, the parameters describing the kinetics on the surface of Si and Ge are fitted on a small set of experimental results. To this goal, Si vertical microcrystals have been grown, while for Ge the fitting parameters have been obtained from data from the literature. Once calibrated, the predictive capabilities of the model are demonstrated and exploited for investigating new pattern geometries and crystal morphologies, offering a guideline for the design of new 3D heterostructures. The reported methodology is intended to be a general approach for investigating faceted growth under far-from-equilibrium conditions.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2045-2322Test

الوصول الحر: https://doaj.org/article/35a75d67142b445e9a69f18063381a49Test

المؤلفون: Miguel Montesinos-Ballester, Vladyslav Vakarin, Joan Manel Ramirez, Qiankun Liu, Carlos Alonso-Ramos, Xavier Le Roux, Jacopo Frigerio, Andrea Ballabio, Andrea Barzaghi, Lucas Deniel, David Bouville, Laurent Vivien, Giovanni Isella, Delphine Marris-Morini

المصدر: Communications Materials, Vol 1, Iss 1, Pp 1-6 (2020)

مصطلحات موضوعية: Materials of engineering and construction. Mechanics of materials, TA401-492

الوصف: Mid-infrared optical modulators are important for detecting compounds in a wide range of applications, but are typically limited to short wavelengths. Now, a SiGe waveguide is used to fabricate an optical modulator that can reach wavelengths spanning 5.5 µm to 11 µm.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2662-4443Test

الوصول الحر: https://doaj.org/article/8691f779a5884daeaf5b771b7e2fd0afTest

المؤلفون: Xavier Le Roux, Carlos Alonso-Ramos, David Bouville, Laurent Vivien, Qiankun Liu, Giovanni Isella, Vladyslav Vakarin, Jacopo Frigerio, Andrea Barzaghi, Lucas Deniel, Delphine Marris-Morini, Andrea Ballabio, Joan Manel Ramirez, Miguel Montesinos-Ballester

المساهمون: Centre de Nanosciences et de Nanotechnologies (C2N), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Politecnico di Milano [Milan] (POLIMI)

المصدر: Communications Materials, Vol 1, Iss 1, Pp 1-6 (2020)
Communications Materials
Communications Materials, 2020, 1 (1), ⟨10.1038/s43246-019-0003-8⟩

مصطلحات موضوعية: Materials science, Physics::Optics, 02 engineering and technology, 01 natural sciences, law.invention, 010309 optics, law, 0103 physical sciences, Broadband, General Materials Science, Materials of engineering and construction. Mechanics of materials, Range (particle radiation), [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Wavelength range, business.industry, 021001 nanoscience & nanotechnology, Wavelength, Optical modulator, Mechanics of Materials, Modulation, TA401-492, Optoelectronics, Photonics, 0210 nano-technology, business, Waveguide

الوصف: Waveguide integrated optical modulators in the mid-infrared wavelength range are of significant interest for molecular spectroscopy. This is because on-chip synchronous detection can improve the performance of detection systems and can also be used for free-space communications where optical modulators working in atmospheric transparency windows are needed. Here we report optical modulation in a mid-infrared photonic circuit, reaching wavelengths larger than 8 µm. Optical modulation in the wavelength range from 5.5 to 11 µm is shown, relying on a broadband Ge-rich graded-SiGe platform. This demonstration experimentally confirms the free-carrier absorption effect modeling. These results pave the way towards efficient high-performance electrically-driven integrated optical modulators in the mid-infrared wavelength range. Mid-infrared optical modulators are important for detecting compounds in a wide range of applications, but are typically limited to short wavelengths. Now, a SiGe waveguide is used to fabricate an optical modulator that can reach wavelengths spanning 5.5 µm to 11 µm.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7cc435943a9e4ec60d7ba2a6e920dbd0Test
https://doaj.org/article/8691f779a5884daeaf5b771b7e2fd0afTest