Este esfuerzo fue totalmente apoyada por el Departamento de Educación de EE.UU., Oficina de Ciencias de Basic Energy, Ciencias de los Materiales y de la División de Ingeniería.

1. Muestra Fabricación Crecimiento <ol><li> Limpiar un 5 mm x 5 mm x mm sustrato de cristal único 0.5 tiene un ángulo de corte incorrectamente &lt;0,1 grado tales como SrTiO 3 o LaAlO3 con acetona y después con agua en un limpiador de ultrasonidos durante 10 min cada uno. Para obtener una terminación TiO 2 en SrTiO3, grabar el sustrato en 10% de fluoruro de hidrógeno durante 30 segundos y enjuague en agua durante 1 min, seguido de un recocido a 1100 ° C durante 10 hr. Después de limpiar, montar el sustrato en un calentador adecuado para las condiciones de ultra alto vacío. </li><li> Montar el calentador en la cámara de vacío PLD y abrir la fuente de oxígeno de la cámara para llenar la cámara con 2 x oxígeno 10E-5 Torr. Elevar la temperatura del calentador a 800 ° C y deje que se recocido durante 20 min. La temperatura puede ser controlada utilizando un pirómetro controlado por ordenador o un termopar. </li><li> Para comenzar la deposición de la película, iniciar el excimer láser de impulsos usando una fluencia de láser de 1 a 2 J / cm 2 y la frecuencia del láser de 1o 2 Hz. Los pulsos de láser se golpear el material objetivo y generar un flujo de penacho. El flujo puede penetrar a través del entorno de oxígeno y se depositan sobre el sustrato. </li><li> Reflejo de difracción de electrones de alta energía (RHEED) se puede utilizar para controlar el crecimiento celular y la unidad de confirmar la calidad de la superficie 7. Esta técnica permite la verificación del espesor muy claro. </li><li> Cuando la película es del espesor deseado, apague el láser y disminuir la temperatura del calentador a 5 º C / min. Una vez que el calentador se enfría a temperatura ambiente, apague la fuente de oxígeno y extraer la muestra. </li><li> Ex situ de recocido se puede utilizar en materiales de óxido para eliminar las deficiencias de oxígeno que pueden estar presentes después de un crecimiento o después de largos períodos en el vacío. Colocar la muestra en un horno de tubo bajo 1 atm de oxígeno que fluye. Elevar la temperatura desde 20 ° C a 700 ° C a 5 ° C / min, recocido durante 2 horas y, a continuación, disminuir la temperatura de 700 ° C a 20 ° C a 2 ° C / min. Un importante note es no publicar recocido a temperaturas más altas que las utilizadas durante el crecimiento cine al llenar vacantes de oxígeno, ya que puede afectar negativamente a la calidad de la superficie y puede influir negativamente en la calidad del cristal. </li></ol> 2. Fabricación fotolitografía <ol><li> Ultrasónicamente limpiar la muestra en acetona y luego con agua durante 10 min cada uno. Un microscopio óptico se puede utilizar para comprobar que la superficie de la muestra está limpio de partículas grandes. (Figura 2a) </li><li> Haga girar la capa una capa de 1 micra de espesor fotosensible. Velocidad de rotación típica y duración son alrededor de 6.000 rpm y 80 segundos, aunque estas cifras dependen de fotoprotector específico usado. Colocar la muestra en un plato térmico a 115 ° C durante 2 minutos para curar la fotoprotección. Compruebe la calidad fotoprotector con un microscopio óptico. El recubrimiento debe aparecer uniforme sin burbujeo. </li><li> Utilice un alineador de máscara para exponer la muestra bajo una máscara de litografía predefinido con luz UV durante 9 segundos con una dosis de exposiciónalrededor de 90 mJ / cm 2. Una vez más estos números serán específicos para la fotoprotección utilizado. Cuando se utiliza resina fotosensible positiva, la parte de la resina fotosensible que está cubierto por la máscara no cambiará su propiedad química mientras que la parte de la PR que está cubierto por la máscara se cambie su propiedad y puede ser disuelto en el revelador química. Se calienta la resina fotosensible y de la muestra a 110 ° C durante 80 segundos para curar además la resina fotosensible expuesta. </li><li> Lavar la muestra en una solución reveladora de 25-35 seg. Sacar la muestra inmediatamente y enjuague con agua durante 30 segundos. Si se utiliza resina fotosensible positiva, la parte de resina fotosensible que está cubierto por la máscara se elimina por lavado, mientras que la parte que está cubierta permanecerá. Tenga en cuenta que la duración de la etapa de revelado es crucial para controlar con precisión las dimensiones fotorresistentes y de calidad (Figura 2b). </li><li> Preparar una solución de yoduro de potasio, ácido clorhídrico y agua de la relación de 01:01:01. Utilice pinzas de plástico para enjuagar tse muestra en el ácido durante aproximadamente 10 segundos. La parte no protegida de la película fina quedará grabado distancia. Lavar inmediatamente la muestra en agua pura durante 60 segundos. Consulte con un microscopio óptico para ver si la película fina ha sido totalmente grabada. Si no es así, añadir 2 a 3 segundos más de grabado ácido y enjuagar inmediatamente con agua pura, y luego puedes volver a intentarlo con un microscopio óptico. Repita este procedimiento hasta que toda la película sin protección es grabado. Este proceso se rige por la fuerza reactivo de ataque y espesor de la película. Velocidades de ataque típicas para muchos manganitos son unos 1-4 nm / segundo para la relación de solución de 01:01:01 se ha descrito anteriormente. </li><li> Enjuague la muestra en acetona durante 20 segundos para eliminar el fotoprotector restante. Compruebe la calidad de la muestra con el microscopio (Figura 2c y 2d). </li></ol> 3. Cable de unión de conexion <ol><li> El uso de un foto-máscara, repita los pasos 2.1 a 2.3 anteriores usando una máscara litográfica que dejarán regiones abiertas en los cables adecuados para el contactoalmohadillas. Evaporar 5 nm de Ti y 100 nm de Au sobre la muestra y enjuague con acetona. Esto eliminará la resina fotosensible y dejar sólo la geometría almohadilla de contacto deseada (Figura 3a). </li><li> Usa GE barniz para montar la muestra sobre el disco de la muestra. Permita 15 minutos para curar. </li><li> Fijar la posición de la muestra en el escenario dispositivo de unión de alambre y utilizar el dispositivo de unión de alambre para conectar cables de Al el disco de muestra de Ti / Au contactos (Figura 3b). A continuación, realice las mediciones eléctricas. </li></ol>

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No hay conflictos de interés declarado.

A diferencia de los materiales semiconductores de elementos individuales tales como Si, la fabricación de materiales complejas puede ser más difícil debido al hecho de que la estructura compleja y múltiples elementos deben tenerse en cuenta. El uso de la fotolitografía para fabricar dispositivos de óxido de complejos es relativamente bajo coste y rápida de prototipos a diferencia de otras técnicas de confinamiento. Sin embargo, hay algunas limitaciones importantes para entender. La fotolitografía tiene una limi...

El primero y uno de los pasos más importantes para los dispositivos de alta calidad es el crecimiento de películas delgadas epitaxiales de óxido. Un sustrato de cristal único se utiliza como una &quot;plantilla&quot; para depositar los materiales de blanco. Entre los diferentes métodos de deposición, deposición por láser pulsado (PLD) es una de las mejores maneras de adquirir buenas películas delgadas de calidad 4,5. Los procesos de crecimiento implican calentar el sustrato a alrededor de 800 ° C en un entorno de oxígeno y el uso de pulsos de láser para golpear el material objetivo y generar un flujo a ser depositado sobre el sustrato. El sistema típico se muestra en la Figura 1. Aunque se han mostrado películas no pautadas para revelar nueva física exóticos 6, la reducción de dimensión película ofrece más oportunidades para explorar nuevos fenómenos y fabricación del dispositivo. La fotolitografía se puede utilizar para reducir el tamaño de la dimensión de la muestra en el plano hacia abajo para el orden de 1 m. El protocolo detallado del proceso de fotolitografía sese discutirá más adelante. Esta técnica es compatible con sustratos más utilizados que permite la investigación de los efectos de confinamiento en películas epitaxiales celebradas en diferentes estados de tensión. Dado que muchos óxidos complejos tienen características interesantes a bajas temperaturas y / o campos magnéticos de alta, la conexión electrónica entre el dispositivo y el equipo de medición es muy importante. Contactos de alta calidad se pueden formar por evaporación de Au almohadillas de contacto en una geometría 4-sonda y con el uso de un dispositivo de unión de alambre para hacer las conexiones entre las pastillas y el dispositivo de medición. Cuando se hace correctamente, estas conexiones pueden soportar fácilmente entornos de medición extremas dentro de amplios rangos de temperatura de 4 K a 400 K y los rangos de campos magnéticos de hasta ± 9 T.

<table border="1">
 <tbody>
 <tr>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>Reagent/Material</td>
 </tr>
 <tr>
 <td>SrTiO3(001) &amp; LaAlO3(100) substrates</td>
 <td>CrysTec GmbH</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Microposit S1813 Photoresist</td>
 <td>Shipley</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>CD-26 Developer</td>
 <td>Shipley</td>
 <td>38490</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>GE varnish</td>
 <td>Lakeshore</td>
 <td>VGE-7031</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>&nbsp;</td>
 <td>Equipment</td>
 </tr>
 <tr>
 <td>Reflected High Energy Electron Diffraction (RHEED)</td>
 <td>Staib Instruments</td>
 <td>&nbsp;</td>
 <td>35 kV TorrRHEED</td>
 </tr>
 <tr>
 <td>Mask Aligner</td>
 <td>ABM</td>
 <td>Model 85-3 (350 W) Lightsource</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Resistivity Puck</td>
 <td>Quantum Design</td>
 <td>P102</td>
 <td>&nbsp;</td>
 </tr>
 <tr>
 <td>Wire Bonder</td>
 <td>Kulicke &amp; Soffa</td>
 <td>04524-0XDA-000-00</td>
 <td>&nbsp;</td>
 </tr>
 </tbody>
</table>

fabrication of spatially confined complex oxides

Materiales complejos tales como superconductores de alta Tc, multiferroicos y magnetorresistores colosales tienen propiedades electrónicas y magnéticas que surgen de la fuerte correlación de electrones inherentes que se encuentran dentro de ellas. Estos materiales también pueden poseer una separación de fases electrónico en el que las regiones de muy diferente comportamiento resistivo y magnéticos pueden coexistir dentro de un material de aleación de cristal único. Al reducir la escala de estos materiales a escalas de longitud en y por debajo del tamaño inherente de los dominios electrónicos, comportamientos nuevos pueden estar expuestos. Debido a esto y al hecho de que los beneficios de carga celosía-orbitales parámetros de orden cada implican longitudes de correlación, lo que reduce espacialmente estos materiales para las mediciones de transporte es un paso crítico en la comprensión de la física fundamental que impulsa a comportamientos complejos. Estos materiales también ofrecen un gran potencial para convertirse en la próxima generación de dispositivos electrónicos 1-3. Por lo tanto, la fabricación de pocas dimensiones nano-omicro-estructuras es muy importante para lograr una nueva funcionalidad. Esto implica múltiples procesos controlables de crecimiento de películas delgadas de alta calidad a la caracterización de la propiedad electrónica precisa. A continuación, presentamos los protocolos de fabricación de microestructuras de alta calidad para dispositivos manganite óxidos complejos. Se presentan descripciones detalladas y el equipo requerido de crecimiento de películas delgadas, foto-litografía, y alambre de unión.

Este documento se centra principalmente en los aspectos de fotolitografía y el alambre de unión de la preparación de la muestra. Más información sobre los procedimientos de crecimiento de película se pueden encontrar en nuestras otras publicaciones recientes 8. Fotolitografía es un método importante para controlar dimensionalidad en óxidos complejos para el propósito de investigar longitudes de correlación de electrones y la separación de fase electrónica 9-13.</...

Watch this Scientific Journal Video about Fabrication of Spatially Confined Complex Oxides at JoVE.com

Fabrication of Spatially Confined Complex Oxides

Se describe el uso de la deposición de láser pulsado (PLD), técnicas de fotolitografía y de alambre de unión para crear escala óxidos complejos dispositivos micrométricos. El PLD se utiliza para crecer películas delgadas epitaxiales. Técnicas de fotolitografía y el alambre de unión se introducen para crear dispositivos prácticos para efectos de su valoración.

La fabricación de óxidos complejos espacialmente confinados

Complex materials such as high Tc superconductors, multiferroics, and colossal magnetoresistors have electronic and magnetic properties that arise from ...

fabrication-of-spatially-confined-complex-oxides

Research

JoVE Journal

Engineering

9.4K vistas.  Oak Ridge National Laboratory. Se describe el uso de la deposición de láser pulsado (PLD), técnicas de fotolitografía y de alambre de unión para crear escala óxidos complejos dispositivos micrométricos. El PLD se utiliza para crecer películas delgadas epitaxiales. Técnicas de fotolitografía y el alambre de unión se introducen para crear dispositivos prácticos para efectos de su valoración.

Video: Fabrication of Spatially Confined Complex Oxides

Measuring Spatially- and Directionally-varying Light Scattering from Biological Material

Light interacts with an organism's integument on a variety of spatial scales. For example in an iridescent bird: nano-scale structures produce color; the milli-scale structure of barbs and barbules largely determines the directional pattern of reflected light; and through the macro-scale spatial structure of overlapping, curved feathers, these directional effects create the visual texture. Milli-scale and macro-scale effects determine where on the organism's body, and from what viewpoints and under what illumination, the iridescent colors are seen. Thus, the highly directional flash of brilliant color from the iridescent throat of a hummingbird is inadequately explained by its nano-scale structure alone and questions remain. From a given observation point, which milli-scale elements of the feather are oriented to reflect strongly? Do some species produce broader "windows" for observation of iridescence than others? These and similar questions may be asked about any organisms that have evolved a particular surface appearance for signaling, camouflage, or other reasons.
In order to study the directional patterns of light scattering from feathers, and their relationship to the bird's milli-scale morphology, we developed a protocol for measuring light scattered from biological materials using many high-resolution photographs taken with varying illumination and viewing directions. Since we measure scattered light as a function of direction, we can observe the characteristic features in the directional distribution of light scattered from that particular feather, and because barbs and barbules are resolved in our images, we can clearly attribute the directional features to these different milli-scale structures. Keeping the specimen intact preserves the gross-scale scattering behavior seen in nature. The method described here presents a generalized protocol for analyzing spatially- and directionally-varying light scattering from complex biological materials at multiple structural scales.

We present a non-destructive method for sampling spatial variation in the direction of light scattered from structurally complex materials. By keeping the material intact, we preserve gross-scale scattering behavior, while concurrently capturing fine-scale directional contributions with high-resolution imaging. Results are visualized in software at biologically-relevant positions and scales.

Medición espacialmente y direccionalmente variable dispersión de luz de material biológico

Light interacts with an organism's integument on a variety of spatial scales. For example in an iridescent bird: nano-scale structures produce color; the ...

Investigación

Ingeniería

Fabrication of Nano-engineered Transparent Conducting Oxides by Pulsed Laser Deposition

Nanosecond Pulsed Laser Deposition (PLD) in the presence of a background gas allows the deposition of metal oxides with tunable morphology, structure, density and stoichiometry by a proper control of the plasma plume expansion dynamics. Such versatility can be exploited to produce nanostructured films from compact and dense to nanoporous characterized by a hierarchical assembly of nano-sized clusters. In particular we describe the detailed methodology to fabricate two types of Al-doped ZnO (AZO) films as transparent electrodes in photovoltaic devices: 1) at low O2 pressure, compact films with electrical conductivity and optical transparency close to the state of the art transparent conducting oxides (TCO) can be deposited at room temperature, to be compatible with thermally sensitive materials such as polymers used in organic photovoltaics (OPVs); 2) highly light scattering hierarchical structures resembling a forest of nano-trees are produced at higher pressures. Such structures show high Haze factor (&gt;80%) and may be exploited to enhance the light trapping capability. The method here described for AZO films can be applied to other metal oxides relevant for technological applications such as TiO2, Al2O3, WO3 and Ag4O4.

We describe the experimental method to deposit nanostructured oxide thin films by nanosecond Pulsed Laser Deposition (PLD) in the presence of a background gas. By using this method Al-doped ZnO (AZO) films, from compact to hierarchically structured as nano-tree forests, can be deposited.

La fabricación de nano-ingeniería óxidos conductores transparentes por deposición por láser pulsado

Nanosecond Pulsed  Laser Deposition (PLD) in the presence of a background gas allows the deposition  of metal oxides with tunable morphology, structure, ...

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

An experimental study is performed to measure the terminal settling velocities of spherical particles in surfactant based shear thinning viscoelastic (VES) fluids. The measurements are made for particles settling in unbounded fluids&#160;and fluids between parallel walls. VES fluids over a wide range of rheological properties are prepared and rheologically characterized. The rheological characterization involves steady shear-viscosity and dynamic oscillatory-shear measurements to quantify the viscous and elastic properties respectively. The settling velocities under unbounded conditions are measured in beakers having diameters at least 25x the diameter of particles. For measuring settling velocities between parallel walls, two experimental cells with different wall spacing are constructed. Spherical particles of varying sizes are gently dropped in the fluids and allowed to settle. The process is recorded with a high resolution video camera and the trajectory of the particle is recorded using image analysis software. Terminal settling velocities are calculated from the data.
The impact of elasticity on settling velocity in unbounded fluids is quantified by comparing the experimental settling velocity to the settling velocity calculated by the inelastic drag predictions of Renaud et al.1&#160;Results show that elasticity of fluids can increase or decrease the settling velocity. The magnitude of reduction/increase is a function of the rheological properties of the fluids and properties of particles. Confining walls are observed to cause a retardation effect on settling and the retardation is measured in terms of wall factors.

This paper demonstrates the experimental procedure to measure terminal settling velocities of spherical particles in surfactant-based shear thinning viscoelastic fluids. Fluids over a wide range of rheological properties are prepared and settling velocities are measured for a range of particle sizes in unbounded fluids and fluids between parallel walls.

Medición Experimental De La Velocidad De Sedimentación De Partículas Esféricas En Fluidos Viscoelásticos De Adelgazamiento No Confinados Y Confinados A Base De Surfactante

An experimental study is performed to measure the terminal settling velocities of spherical particles in surfactant based shear thinning viscoelastic ...

Fabrication and Testing of Microfluidic Optomechanical Oscillators

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including microresonators. However, because of the increased acoustic radiative losses during direct liquid immersion of optomechanical devices, almost all published optomechanical experiments have been performed in solid phase. This paper discusses a recently introduced hollow microfluidic optomechanical resonator. Detailed methodology is provided to fabricate these ultra-high-Q microfluidic resonators, perform optomechanical testing, and measure radiation pressure-driven breathing mode and SBS-driven whispering gallery mode parametric vibrations. By confining liquids inside the capillary resonator, high mechanical- and optical- quality factors are simultaneously maintained.

Parametric optomechanical excitations have recently been experimentally demonstrated in microfluidic optomechanical resonators by means of optical radiation pressure and stimulated Brillouin scattering. This paper describes the fabrication of these microfluidic resonators along with methodologies for generating and verifying optomechanical oscillations.

Fabricación y Pruebas de microfluidos optomecánicos Osciladores

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including ...

Atomically Traceable Nanostructure Fabrication

Reducing the scale of etched nanostructures below the 10 nm range eventually will require an atomic scale understanding of the entire fabrication process being used in order to maintain exquisite control over both feature size and feature density. Here, we demonstrate a method for tracking atomically resolved and controlled structures from initial template definition through final nanostructure metrology, opening up a pathway for top-down atomic control over nanofabrication. Hydrogen depassivation lithography is the first step of the nanoscale fabrication process followed by selective atomic layer deposition of up to 2.8 nm of titania to make a nanoscale etch mask. Contrast with the background is shown, indicating different mechanisms for growth on the desired patterns and on the H passivated background. The patterns are then transferred into the bulk using reactive ion etching to form 20 nm tall nanostructures with linewidths down to ~6 nm. To illustrate the limitations of this process, arrays of holes and lines are fabricated. The various nanofabrication process steps are performed at disparate locations, so process integration is discussed. Related issues are discussed including using fiducial marks for finding nanostructures on a macroscopic sample and protecting the chemically reactive patterned Si(100)-H surface against degradation due to atmospheric exposure.

We report a protocol for combining the atomic metrology of the Scanning Tunneling Microscope for surface patterning with selective Atomic Layer Deposition and Reactive Ion Etching. Using a robust process involving numerous atmospheric exposures and transport, 3D nanostructures with atomic metrology are fabricated.

La fabricación de nanoestructuras Atómicamente trazable

Reducing the scale of etched nanostructures below the 10 nm range eventually will require an atomic scale understanding of the entire fabrication process ...

Fabrication and Characterization of Superconducting Resonators

Superconducting microwave resonators are of interest for a wide range of applications, including for their use as microwave kinetic inductance detectors (MKIDs) for the detection of faint astrophysical signatures, as well as for quantum computing applications and materials characterization. In this paper, procedures are presented for the fabrication and characterization of thin-film superconducting microwave resonators. The fabrication methodology allows for the realization of superconducting transmission-line resonators with features on both sides of an atomically smooth single-crystal silicon dielectric. This work describes the procedure for the installation of resonator devices into a cryogenic microwave testbed and for cool-down below the superconducting transition temperature. The set-up of the cryogenic microwave testbed allows one to do careful measurements of the complex microwave transmission of these resonator devices, enabling the extraction of the properties of the superconducting lines and dielectric substrate (e.g., internal quality factors, loss and kinetic inductance fractions), which are important for device design and performance.

Superconducting microwave resonators are of interest for detection of light, quantum computing applications and materials characterization. This work presents a detailed procedure for fabrication and characterization of superconducting microwave resonator scattering parameters.

Fabricación y caracterización de resonadores superconductores

Superconducting microwave resonators are of interest for a wide range of applications, including for their use as microwave kinetic inductance detectors ...

Simultaneous Multi-surface Anodizations and Stair-like Reverse Biases Detachment of Anodic Aluminum Oxides in Sulfuric and Oxalic Acid Electrolyte

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental sciences and industrial applications owing to their periodic arrangement of nanopores with relatively high aspect ratio. However, the techniques reported so far, which could be only valid for mono-surface anodization, show critical disadvantages, i.e., time-consuming as well as complicated procedures, requiring toxic chemicals, and wasting valuable natural resources. In this paper, we demonstrate a facile, efficient, and environmentally clean method to fabricate nanoporous AAOs in sulfuric and oxalic acid electrolytes, which can overcome the limitations that result from conventional AAO fabricating methods. First, plural AAOs are produced at one time through simultaneous multi-surfaces anodization (SMSA), indicating mass-producibility of the AAOs with comparable qualities. Second, those AAOs can be separated from the aluminum (Al) substrate by applying stair-like reverse biases (SRBs) in the same electrolyte used for the SMSAs, implying simplicity and green technological characteristics. Finally, a unit sequence consisting of the SMSAs sequentially combined with SRBs-based detachment can be applied repeatedly to the same Al substrate, which reinforces the advantages of this strategy and also guarantees the efficient usage of natural resources.

A protocol for fabricating nanoporous anodic aluminum oxides via simultaneous multi-surfaces anodization followed by stair-like reverse biases detachments is presented. It can be applied repeatedly to the same aluminum substrate, exhibiting a facile, high-yield, and environmentally clean strategy.

Anodizations multi-emerger simultánea y sesgos inversa escalera-como destacamento de anódico de aluminio óxidos sulfúricos y electrolito de ácido oxálico

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental ...

Fabrication of Superhydrophobic Metal Surfaces for Anti-Icing Applications

Several ways to produce superhydrophobic metal surfaces are presented in this work. Aluminum was chosen as the metal substrate due to its wide use in industry. The wettability of the produced surface was analyzed by bouncing drop experiments and the topography was analyzed by confocal microscopy. In addition, we show various methodologies to measure its durability and anti-icing properties. Superhydrophobic surfaces hold a special texture that must be preserved to keep their water-repellency. To fabricate durable surfaces, we followed two strategies to incorporate a resistant texture. The first strategy is a direct incorporation of roughness to the metal substrate by acid etching. After this surface texturization, the surface energy was decreased by silanization or fluoropolymer deposition. The second strategy is the growth of a ceria layer (after surface texturization) that should enhance the surface hardness and corrosion resistance. The surface energy was decreased with a stearic acid film.
The durability of the superhydrophobic surfaces was examined by a particle impact test, mechanical wear by lateral abrasion, and UV-ozone resistance. The anti-icing properties were explored by studying the ability to repeal subcooled water, freezing delay, and ice adhesion.

We illustrate several methodologies to produce superhydrophobic metal surfaces and to explore their durability and anti-icing properties.

Fabricación de superficies metálicas superhidrófobos para aplicaciones anti-hielo

Several ways to produce superhydrophobic metal surfaces are presented in this work. Aluminum was chosen as the metal substrate due to its wide use in ...

Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides

Here, we present a procedure for the synthesis of bulk and thin film multicomponent (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (Co variant) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (Cu variant) entropy-stabilized oxides. Phase pure and chemically homogeneous (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (x = 0.20, 0.27, 0.33) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (x = 0.11, 0.27) ceramic pellets are synthesized and used in the deposition of ultra-high quality, phase pure, single crystalline thin films of the target stoichiometry. A detailed methodology for the deposition of smooth, chemically homogeneous, entropy-stabilized oxide thin films by pulsed laser deposition on (001)-oriented MgO substrates is described. The phase and crystallinity of bulk and thin film materials are confirmed using X-ray diffraction. Composition and chemical homogeneity are confirmed by X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The surface topography of thin films is measured with scanning probe microscopy. The synthesis of high quality, single crystalline, entropy-stabilized oxide thin films enables the study of interface, size, strain, and disorder effects on the properties in this new class of highly disordered oxide materials.

The synthesis of high quality bulk and thin film (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O entropy-stabilized oxides is presented.

A granel y síntesis de la película fina de composición variantes óxidos entropía estabilizada

Here, we present a procedure for the synthesis of bulk and thin film multicomponent (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (Co variant) and ...

Fabrication of Soft Pneumatic Network Actuators with Oblique Chambers

Soft pneumatic network actuators have become one of the most promising actuation devices in soft robotics which benefits from their large bending deformation and low input. However, their monotonous bending motion form in two-dimensional (2-D) space keeps them away from wide applications. This paper presents a detailed fabrication method of soft pneumatic network actuators with oblique chambers, to explore their motions in three-dimensional (3-D) space. The design of oblique chambers enables actuators with tunable coupled bending and twisting capabilities, which gives them the possibility to move dexterously in flexible manipulators, to become biologically inspired robots and medical devices. The fabrication process is based on the molding method, including the silicone elastomer preparation, chamber and base parts fabrication, actuator assembly, tubing connections, checks for leaks, and actuator repair. The fabrication method guarantees the rapid manufacturing of a series of actuators with only a few modifications in the molds. The test results show the high quality of the actuators and their prominent bending and twisting capabilities. Experiments of the gripper demonstrate the advantages of the development in adapting to objects with different diameters and providing sufficient friction.

Here we present a fabrication method of soft pneumatic network actuators with oblique chambers. The actuators are capable of generating coupled bending and twisting motions, which broadens their application in soft robotics.

Methods Article

La fabricación de óxidos complejos espacialmente confinados