Este esforço foi totalmente apoiada por os EUA DOE, Instituto de ciências básicas da energia, Ciências dos Materiais e Divisão de Engenharia.

1. Amostra Crescimento Fabrication <ol><li> Limpeza de 5 mm x 5 mm x 0,5 mm de substrato de cristal único com um ângulo miscut &lt;0,1 graus, como SrTiO 3 ou LaAlO 3 com acetona e em seguida com água num aparelho de limpeza de ultra-sons durante 10 minutos cada. Para obter uma terminação de TiO 2 em SrTiO 3, etch do substrato em 10% de fluoreto de hidrogénio durante 30 seg e enxaguamento em água durante 1 min, seguido de um recozimento a 1100 ° C durante 10 horas. Após a limpeza, montar o substrato sobre um aquecedor apropriado para as condições de ultra-alto vácuo. </li><li> Montar o aquecedor para dentro da câmara de vácuo PLD e abrir a câmara de fonte de oxigénio para encher a câmara com 2 x 10E-5 Torr oxigénio. Aumentar a temperatura do aquecedor para 800 ° C e deixar de recozimento durante 20 min. A temperatura pode ser controlada por meio de um pirómetro controlado por computador ou de um termopar. </li><li> Para começar a deposição do filme, iniciar a excimer laser utilizando pulsadas uma fluência do laser de 1 a 2 J / cm 2, e de um laser de frequênciaou 2 Hz. Os pulsos de laser vai bater o material do alvo e gerar um fluxo de pluma. O fluxo vai penetrar através do ambiente de oxigénio e de depósito sobre o substrato. </li><li> Reflexo alta Difracção Electron energia (RHEED) pode ser utilizado para monitorizar o crescimento da célula unitária e confirmar a qualidade da superfície 7. Esta técnica permite o monitoramento espessura muito claro. </li><li> Quando o filme é com a espessura desejada, desliga o laser e diminuir a temperatura do aquecedor, a 5 ° C / min. Quando o aquecedor é arrefecida até à temperatura ambiente, desligar a fonte de oxigénio e remover a amostra. </li><li> Ex situ de recozimento pode ser utilizado em materiais de óxido para remover irregularidades de oxigénio que podem estar presentes após o crescimento ou depois de longos períodos de tempo em condições de vácuo. Coloque a amostra em um forno tubular sob 1 atm de fluxo de oxigênio. Elevar a temperatura de 20 ° C a 700 ° C a 5 ° C / min, o recozimento durante 2 horas e, em seguida, diminuir a temperatura de 700 ° C a 20 ° C a 2 ° C / min. Um importante nãote é nunca pós-recozimento em temperaturas mais altas do que as usadas durante o crescimento filme, quando o preenchimento de vagas de oxigênio, pois isso pode afetar negativamente a qualidade da superfície e pode influenciar negativamente a qualidade do cristal. </li></ol> 2. Fabricação de fotolitografia <ol><li> Ultrassonicamente limpar a amostra em acetona e em seguida com água durante 10 minutos cada. Um microscópio óptico pode ser usada para verificar que a superfície da amostra é limpo de partículas grandes. (Figura 2a) </li><li> Gire casaco uma camada de 1 mícron fotorresiste de espessura. Velocidade de centrifugação e duração típica são cerca de 6000 rpm e 80 seg embora estes números são dependentes fotosensitivo específico utilizado. Colocar a amostra numa placa de calor a 115 ° C durante 2 minutos para curar o material fotosensitivo. Verifique a qualidade photoresist sob um microscópio óptico. O revestimento deve aparecer uniforme sem borbulhar. </li><li> Usar um alinhador de máscara para expor a amostra sob uma máscara de litografia predefinida com luz UV durante 9 seg, com uma dose de exposiçãocerca de 90 mJ / cm 2. Novamente estes números vão ser específico para o foto-resistente utilizado. Quando fotossensível positivo é utilizado, a peça de material fotosensitivo que é coberta pela máscara não vai alterar a sua propriedade química, enquanto a parte do PR, que é revelado pela máscara vai alterar a sua propriedade e pode ser dissolvido no revelador químico. Aquece-se a foto-resistente e de amostra a 110 ° C durante 80 segundos para curar ainda mais a fotossensível exposta. </li><li> Lavar a amostra em uma solução de desenvolvimento para 25-35 seg. Retire a amostra imediatamente e lave em água por 30 segundos. Se fotossensível positivo é utilizado, a peça de material fotosensitivo que é revelado pela máscara será lavada, enquanto a parte que é coberta permanecerá. Note-se que a duração da etapa de desenvolvimento é crucial para controlar com precisão a dimensão e qualidade de resina fotossensível (Figura 2b). </li><li> Prepara-se uma solução de iodeto de potássio, ácido clorídrico e água de relação 1:1:1. Use uma pinça de plástico para enxaguar tele amostra no ácido durante cerca de 10 seg. A parte desprotegido da película fina será gravado fora. Lave imediatamente a amostra em água pura por 60 seg. Verificar com um microscópio óptico para ver se a película fina foi totalmente gravado. Se não, adicione mais 2 a 3 segundos de ataque ácido e lave imediatamente com água pura, em seguida, verificar novamente com um microscópio óptico. Repita este procedimento até que todo o filme é gravado desprotegido distância. Este processo é regulado pela força produto corrosivo e espessura da película. Taxas de corrosão típicas para muitos manganitas são cerca de 1-4 nm / segundo para a relação 1:01:01 solução descrita acima. </li><li> Lavar a amostra em acetona durante 20 segundos para remover o material fotosensitivo restante. Verifique a qualidade da amostra com microscópio (Figura 2C e 2D). </li></ol> 3. Conexão Wire-bonding <ol><li> Usando uma foto-máscara, repita os passos acima 2,1-2,3 usando uma máscara de litografia que vai deixar regiões abertas nos fios adequados para contatopads. Evapora-se de 5 nm e 100 nm Ti Au sobre a amostra e enxaguar em acetona. Isto irá remover o material fotosensitivo e deixar apenas a geometria desejada almofada de contacto (Figura 3a). </li><li> Use GE verniz para montar a amostra sobre o disco amostra. Deixar 15 minutos para curar. </li><li> Corrigir a posição da amostra em fase fio Bonder e usar o fio Bonder para conectar os fios Al do disco de amostra de Ti / Au contactos (Figura 3b). Em seguida, realizar medições elétricas. </li></ol>

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Ao contrário do elemento de materiais semicondutores individuais, tais como átomos de Si, o fabrico de materiais complexos pode ser mais difícil devido ao facto de a estrutura complexa, com vários elementos devem ser tidos em consideração. O uso de fotolitografia para fabricar dispositivos de óxido complexos é de custo relativamente baixo e rápido ao protótipo em oposição a outras técnicas de confinamento. No entanto, existem algumas limitações importantes para entender. Fotolitografia tem uma limitação...

O primeiro e um dos passos mais importantes para dispositivos de alta qualidade é o crescimento de filmes finos de óxido epitaxiais. Um único substrato de cristal é usado como um &quot;template&quot; para depositar os materiais-alvo. Entre os diferentes métodos de deposição, deposição por laser pulsado (PLD) é uma das melhores maneiras de adquirir boa qualidade filmes finos 4,5. Os processos de crescimento envolvem o aquecimento do substrato a cerca de 800 ° C num ambiente de oxigénio e usando pulsos de laser para atingir o material do alvo e gerar um fluxo a ser depositado sobre o substrato. O sistema típico é mostrado na Figura 1. Enquanto filmes unpatterned foram mostrados para revelar exóticas nova física 6, reduzindo dimensão filme oferece mais oportunidades para explorar novos fenômenos e fabricação do dispositivo. Fotolitografia pode ser usado para diminuir a dimensão da amostra no plano para baixo da ordem de 1 mM. O protocolo detalhado do processo de fotolitografia vontadeser discutido abaixo. Esta técnica é compatível com substratos mais utilizados que permite a investigação de efeitos de confinamento em filmes epitaxiais realizadas em diferentes estados de tensão. Uma vez que muitos óxidos complexos possuem características interessantes a baixas temperaturas e / ou de campos magnéticos elevados, a ligação electrónica entre o dispositivo e equipamento de medição é muito importante. Contatos de alta qualidade podem ser formadas por evaporação almofadas contato Au em uma geometria sonda 4 e com o uso de um fio Bonder para fazer conexões entre as almofadas e dispositivos de medição. Quando feito corretamente, essas conexões pode facilmente resistir a ambientes extremos de medição dentro de amplas faixas de temperatura de 4 K para 400 K e varia de campos magnéticos de até ± 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

Materiais complexos, como os supercondutores de alta Tc, multiferróicos e magneto colossais têm propriedades eletrônicas e magnéticas que surgem a partir das inerentes fortes correlações de elétrons que residem dentro deles. Estes materiais também podem possuir a separação de fases electrónica na qual as regiões do comportamento magnético resistiva e vastamente diferentes podem coexistir num único cristal de material de liga. Ao reduzir a dimensão destes materiais para escalas de comprimento no e abaixo do tamanho inerente dos domínios electrónicos, novos comportamentos podem ser expostos. Devido a isso e ao fato de que os parâmetros de ordem spin-charge-treliça-orbital cada envolver comprimentos de correlação, espacialmente reduzir esses materiais para medidas de transporte é um passo fundamental para a compreensão da física fundamental que impulsiona comportamentos complexos. Estes materiais também oferecem um grande potencial para se tornar a próxima geração de dispositivos eletrônicos 1-3. Assim, a fabricação de grandes quantidades de nano-ou tridimensionalmicro-estruturas é extremamente importante para conseguir uma nova funcionalidade. Trata-se de vários processos controláveis ​​de qualidade de crescimento de filmes finos a exata caracterização propriedade eletrônico. Aqui, apresentamos os protocolos de fabricação de microestruturas de alta qualidade para dispositivos manganitas óxido complexos. Descrições detalhadas e equipamentos necessários de crescimento de filmes finos, foto-litografia, e fio-ligação são apresentados.

Este trabalho concentra-se principalmente nos aspectos de fotolitografia e fio de ligação de preparação da amostra. Mais detalhes sobre os procedimentos de crescimento do filme pode ser encontrado em outras publicações recentes 8. Fotolitografia é um importante método para controlar a dimensionalidade em óxidos complexos com a finalidade de investigar comprimentos de correlação eletrônica e separação de fase eletrônico 9-13. Figura 2 most...

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

Fabrication of Spatially Confined Complex Oxides

Descreve-se a utilização de deposição de laser pulsado (PLD), e as técnicas de fotolitografia fio de ligação para criar dispositivos de óxidos complexos escala micrométrica. A PLD é utilizado para crescer finas películas epitaxiais. Técnicas de fotolitografia e fios de ligação são introduzidos para criar dispositivos práticos para fins de medição.

Fabricação de óxidos complexos 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 visualizações.  Oak Ridge National Laboratory. Descreve-se a utilização de deposição de laser pulsado (PLD), e as técnicas de fotolitografia fio de ligação para criar dispositivos de óxidos complexos escala micrométrica. A PLD é utilizado para crescer finas películas epitaxiais. Técnicas de fotolitografia e fios de ligação são introduzidos para criar dispositivos práticos para fins de medição.

Vídeo: 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.

Medindo espacialmente e direcional variando espalhamento de luz a partir 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 ...

Engenharia

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.

Fabricação de Nano-engenharia transparentes Óxidos Realização por deposição por laser 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.

Medição experimental da velocidade de assentamento de partículas esféricas em fluidos viscosticos não confinados e confinados

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.

Fabricação e Teste de microfluídicos optomechanical 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.

Atomicamente rastreável Fabrication Nanostructure

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.

Fabricação e caracterização de supercondutores Resonators

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 superfície simultâneas e preconceitos reversa da escada, como desprendimento de óxidos de alumínio anódico em ácido sulfúrico e ácido oxálico eletrólito

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.

Fabricação de superfícies de Metal Superhydrophobic para aplicações antigelo

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.

Granel e síntese de película fina de óxidos de entropia-estabilizado em termos de composição variantes

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.