Questo sforzo è stato interamente sostenuto dal DOE statunitense, Ufficio di Scienze energia di base, Scienze dei Materiali e Divisione Engineering.

1. Fabrication Crescita campione <ol><li> Pulire da 5 mm x 5 mm x 0,5 mm singolo substrato di cristallo con un angolo tagliati irregolarmente &lt;0.1 gradi, come SrTiO 3 o LaAlO 3 con acetone e poi l&#39;acqua in un bagno ad ultrasuoni per 10 minuti ciascuno. Per ottenere una terminazione TiO 2 sul SrTiO 3, etch il substrato in 10% di fluoruro di idrogeno per 30 sec e risciacquo in acqua per 1 min, seguito da una ricottura a 1100 ° C per 10 hr. Dopo la pulizia, montare il substrato su una stufa adatta a condizioni di ultra-alto vuoto. </li><li> Montare il riscaldatore nella camera a vuoto PLD e aprire la sorgente di ossigeno camera a riempire la camera con 2 x ossigeno 10E-5 Torr. Alzare la temperatura del riscaldamento a 800 ° C e lasciare ricottura per 20 min. Temperatura può essere controllata mediante un pirometro controllato computer o una termocoppia. </li><li> Per iniziare la deposizione di film, avviare il eccimeri laser pulsato con una fluenza laser di 1 a 2 J / cm 2 e la frequenza del laser di 1o 2 Hz. Gli impulsi laser colpiranno il materiale target e generare un flusso pennacchio. Il flusso penetrerà attraverso l&#39;ambiente di ossigeno e depositare sul substrato. </li><li> Riflessione di alto diffrazione elettronica Energia (RHEED) può essere utilizzato per monitorare la crescita delle cellule dell&#39;unità e confermare la qualità della superficie 7. Questa tecnica consente il monitoraggio dello spessore molto chiaro. </li><li> Quando la pellicola è di spessore desiderato, spegnere il laser e diminuire la temperatura del riscaldatore a 5 ° C / min. Una volta che il riscaldatore viene raffreddato a temperatura ambiente, spegnere la fonte di ossigeno e rimuovere il campione. </li><li> Ex situ ricottura può essere utilizzato su materiali di ossido di rimuovere la carenza di ossigeno che può essere presente dopo la crescita o dopo lunghi periodi nel vuoto. Porre il campione in un forno tubolare sotto 1 atm di ossigeno che scorre. Aumentare la temperatura da 20 ° C a 700 ° C a 5 ° C / min, ricottura per 2 h, e quindi diminuire la temperatura da 700 ° C a 20 ° C a 2 ° C / min. Un importante note è quello di non postare-ricottura a temperature più elevate di quelle utilizzate durante la crescita del film quando si riempie vacanze di ossigeno in quanto questo può influire negativamente sulla qualità della superficie e può influenzare negativamente la qualità di cristallo. </li></ol> 2. Fotolitografia Fabrication <ol><li> Ultrasuoni pulire il campione in acetone e poi acqua per 10 min. Un microscopio ottico può essere utilizzato per verificare che la superficie del campione è pulita di grandi particelle. (Figura 2a) </li><li> Spin cappotto uno strato di 1 micron di spessore photoresist. Velocità di centrifuga tipica e durata sono circa 6,000 rpm e 80 sec se questi numeri dipendono photoresist specifico utilizzato. Porre il campione su una piastra di calore a 115 ° C per 2 min per indurire il fotoresist. Controllare la qualità del photoresist al microscopio ottico. Il rivestimento deve apparire uniforme senza bolle. </li><li> Utilizzare un allineatore maschera per esporre il campione sotto una maschera litografia predefinito con la luce UV per 9 sec con una dose di esposizionecirca 90 mJ / cm 2. Ancora una volta questi numeri saranno specifici per il fotoresist utilizzato. Quando si utilizza photoresist positivo, la parte del fotoresist che è coperta dalla maschera non cambierà la sua struttura chimica, mentre la parte del PR che viene scoperta dalla maschera cambierà la sua proprietà e può essere dissolto nello sviluppatore chimico. Riscaldare il photoresist e campione a 110 ° C per 80 sec per curare ulteriormente il photoresist esposto. </li><li> Lavare il campione in una soluzione di sviluppo per 25-35 sec. Estrarre il campione immediatamente e sciacquare in acqua per 30 sec. Se si utilizza photoresist positivo, la parte di photoresist che viene scoperta dalla maschera sarà lavato via mentre la parte che è coperta rimarrà. Notare che la durata della fase di sviluppo è fondamentale per controllare con precisione le dimensioni e qualità photoresist (Figura 2b). </li><li> Preparare una soluzione di ioduro di potassio, acido cloridrico e acqua di rapporto 1:1:1. Utilizzare le pinzette di plastica per sciacquare tegli campione in acido per circa 10 sec. La parte non protetta del film sottile viene incisa via. Sciacquare immediatamente il campione in acqua pura per 60 sec. Verificare con un microscopio ottico per vedere se il film sottile è stato totalmente inciso. In caso contrario, aggiungere 2 o 3 più secondi di acido etch e risciacquare immediatamente con acqua pura, poi prova di nuovo con un microscopio ottico. Ripetere questa procedura fino a quando tutta la pellicola non protetto è inciso via. Questo processo è governato dalla forza mordenzante e spessore del film. Tassi tipici etch per molti manganiti sono circa 1-4 nm / secondo per il rapporto 1:1:1 soluzione sopra descritta. </li><li> Risciacquare il campione in acetone per 20 secondi per rimuovere il fotoresist rimanente. Controllare la qualità del campione con microscopio (Figura 2c e 2d). </li></ol> 3. Collegamento wire-bonding <ol><li> Utilizzando una foto-maschera, ripetere i passaggi 2,1-2,3 sopra utilizzando una maschera litografia che lasceranno le regioni aperte sui fili adatti al contattopad. Far evaporare 5 nm Ti e 100 nm di Au sul campione e sciacquarlo in acetone. Questo rimuoverà il photoresist e lasciare solo il contatto di geometria di pad desiderato (Figura 3a). </li><li> Utilizzare GE vernice per montare il campione attraverso il disco campione. Lasciare 15 minuti per curare. </li><li> Fissare la posizione del campione sul palco bonder filo e utilizzare il bonder filo per collegare i fili di Al dal disco campione di Ti / Au contatti (Figura 3b). Quindi eseguire le misurazioni elettriche. </li></ol>

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Nessun conflitto di interessi dichiarati.

Diversamente elemento singolo materiali semiconduttori quali Si, la fabbricazione di materiali complessi può essere più difficile per il fatto che la struttura complessa e più elementi devono essere presi in considerazione. L&#39;uso di fotolitografia per fabbricare dispositivi di ossidi complessi è relativamente basso costo e veloce per creare prototipi a differenza di altre tecniche di confinamento. Ci sono però alcune importanti limitazioni per capire. Fotolitografia ha una limitazione spaziale per creare strutt...

Il primo e uno dei passi più importanti verso dispositivi di alta qualità è la crescita epitassiale di film sottili di ossido. Un singolo substrato cristallino è utilizzato come &quot;template&quot; per depositare i materiali bersaglio. Tra i diversi metodi di deposizione, deposizione laser pulsata (PLD) è uno dei modi migliori per acquisire buona qualità film sottili di 4,5. I processi di crescita implicano riscaldare il substrato di circa 800 ° C in assenza di ossigeno e utilizzando impulsi laser per colpire il materiale target e generare un flusso da depositare sul substrato. Il sistema tipico è mostrato in Figura 1. Mentre i film nanostrutturata hanno dimostrato di rivelare nuovi fisica esotica 6, riducendo dimensione pellicola fornisce più opportunità per esplorare nuovi fenomeni e di fabbricazione del dispositivo. Fotolitografia può essere usato per ridurre la dimensione del campione in piano fino all&#39;ordine di 1 pm. Il protocollo dettagliato del processo di fotolitografia volontàessere discusso sotto. Questa tecnica è compatibile con i supporti più utilizzati, che consente per le indagini di effetti di confinamento sul film epitassiali detenuti in vari stati di deformazione. Poiché molti ossidi complessi hanno caratteristiche interessanti a basse temperature e / o campi magnetici elevati, il collegamento tra il dispositivo elettronico e di misura è molto importante. Contatti di alta qualità possono essere formati per evaporazione di Au piazzole di contatto in una geometria a 4 sonda e con l&#39;uso di un bonder filo per creare connessioni tra le pastiglie e dispositivo di misurazione. Se fatto correttamente, questi collegamenti possono facilmente resistere ad ambienti di misura estremi entro ampi intervalli di temperatura di 4 K a 400 K e gli intervalli di campo magnetico fino a ± 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

Materiali complessi come i superconduttori ad alta Tc, multiferroics e Magnetoresistori colossali hanno proprietà elettroniche e magnetiche che nascono dalle forti correlazioni elettroniche intrinseche che si trovano al loro interno. Questi materiali possono anche avere una separazione di fase elettronico in cui le regioni di molto diverso comportamento resistivo e magnetici possono coesistere all&#39;interno di un unico materiale in lega di cristallo. Riducendo la portata di questi materiali per le scale di lunghezza e al di sotto della dimensione intrinseca dei domini elettronici, nuovi comportamenti possono essere esposti. A causa di questo e del fatto che-orbitale spin-carica-reticolo parametri d&#39;ordine ogni coinvolgono lunghezze di correlazione, spazialmente riducendo questi materiali per misure di trasporto è un passo fondamentale nella comprensione della fisica fondamentale che guida comportamenti complessi. Questi materiali offrono anche un grande potenziale per diventare la prossima generazione di dispositivi elettronici 1-3. Così, la fabbricazione di nano-dimensionale bassa omicro-strutture è estremamente importante per ottenere nuove funzionalità. Questo comporta diversi processi controllabili da crescita di film sottili di alta qualità per la caratterizzazione proprietà elettroniche accurate. Qui vi presentiamo i protocolli di fabbricazione di microstrutture di alta qualità per i dispositivi complessi manganite ossido. Descrizioni dettagliate e le attrezzature necessarie di crescita del film sottile, foto-litografia e wire-bonding sono presentati.

Questo documento si concentra principalmente sugli aspetti fotolitografia e wire-bonding di preparazione del campione. Maggiori dettagli sulle procedure di crescita del film si possono trovare in altre nostre pubblicazioni recenti 8. Fotolitografia è un metodo importante per controllare dimensionalità in ossidi complessi per fini di indagine lunghezze correlazione elettronica e la separazione di fase elettronico 9-13. Figura 2 mostra immagini ottiche ...

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

Fabrication of Spatially Confined Complex Oxides

Descriviamo l&#39;uso di deposizione a laser pulsato (PLD), fotolitografia e tecniche di wire-bonding per creare micrometro scala complessi dispositivi di ossidi. La PLD è utilizzato per crescere film sottili epitassiali. Tecniche di fotolitografia e wire-bonding vengono introdotti per creare dispositivi pratici per scopi di misurazione.

Fabbricazione di ossidi complessi spazialmente confinati

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

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9.4K Views.  Oak Ridge National Laboratory. Descriviamo l'uso di deposizione a laser pulsato (PLD), fotolitografia e tecniche di wire-bonding per creare micrometro scala complessi dispositivi di ossidi. La PLD è utilizzato per crescere film sottili epitassiali. Tecniche di fotolitografia e wire-bonding vengono introdotti per creare dispositivi pratici per scopi di misurazione.

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.

Misurare spazialmente e Directionally-variante Light Scattering da materiale biologico

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 ...

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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.

Fabbricazione di nano-ingegneria trasparenti Ossidi Conducting da 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, ...

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.

Misurazione sperimentale della velocità di sedimentazione delle particelle sferiche in fluidi viscoelastici a base di tensioattivi non raffinati e confinati

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.

Fabbricazione e la sperimentazione di microfluidici optomechanical Oscillatori

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 tracciabile nanostrutture

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.

Fabbricazione e caratterizzazione di superconduttori risonatori

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-superficie simultanea e pregiudizi inversa scala-come distaccamento di ossidi di alluminio anodico in solforico e acido ossalico elettrolita

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.

Fabbricazione di superfici superidrofobiche metalliche per applicazioni Anti-Icing

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.

Massa e sintesi di Film sottile di ossidi compositivamente varianti entropia-stabilizzato

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.