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Herein, a simple, facile and versatile protocol was presented to fabricate water-resistant fabrics based on an in situ bio-silicification strategy and fluorinate-free modification. The whole fabrication procedure is green and avoids the need for any fluorinate-containing compounds, environmentally harmful organic solvents and high preparation temperature. The produced fabrics maintained robust lyophobic properties after multiple machine laundry cycles, repeated abrasion cycles, UV irradiation, and organic solvent and strong acid/base attacks. The obtained superhydrophobic fabrics exhibited repeatable self-repairing behaviour against repeated washing and oxygen plasma etching cycles. Our in situ biomimetic silicification strategy for developing robust self-repairing superhydrophobic fabrics using a waterborne fluorinate-free coating system well fits the motifs of green chemistry and will lead to the development of green preparation of other superwetting surfaces.

Oxygen and oxygen-containing plasmas offer great potential for the surface functionalization of polymeric substrates: thermal reactive neutral species are combined with high energy ions to alter both the micro/nanomorphology and composition of polymeric surfaces in a dry process. Although plasma processing is an attractive option for polymer surface modification, plasma–surface interactions are complex and the process design is usually based on a trial-and-error procedure. Toward a comprehensive process design, a hybrid modeling framework, addressing both effects of plasmas on polymeric surfaces, is developed and applied to an investigation of the oxygen-plasma-induced surface roughening of poly(methyl methacrylate). A kinetic Monte Carlo surface model, considering the synergy of neutral species and ions, is used for the calculation of the local etching rate. The novel element of the model is that it takes into account the surface morphology through the calculation of the trajectories of the species joining the surface reactions. The local etching rate is utilized by a profile evolution module based on the level set method to predict the surface roughness evolution. A method for tracking the local variables of the evolving surface profile (e.g. surface coverage), treating a fundamental weakness of the level set method, is proposed and used to effectively reduce the computational time. The results of the framework are validated by comparison to a theoretical model. The prediction of roughness evolution is consistent with measurements vs time and at different operating conditions. The potential of the framework to additionally handle the chemical composition (oxidation) of the surface is demonstrated, enabling the study of the wetting behavior of plasma-etched polymeric surfaces.

In this work, SiNx/a-Si/SiNx caps on conductive coplanar waveguides (CPWs) are proposed for thin film encapsulation of radio-frequency microelectromechanical systems (RF MEMS), in view of the application of these devices in fifth generation (5G) and modern telecommunication systems. Simplification and cost reduction of the fabrication process were obtained, using two etching processes in the same barrel chamber to create a matrix of holes through the capping layer and to remove the sacrificial layer under the cap. Encapsulating layers with etch holes of different size and density were fabricated to evaluate the removal of the sacrificial layer as a function of the percentage of the cap perforated area. Barrel etching process parameters also varied. Finally, a full three-dimensional finite element method-based simulation model was developed to predict the impact of fabricated thin film encapsulating caps on RF performance of CPWs.

The reusability of Ir(111)/α-Al2O3(0001) substrates for graphene CVD in multiple cycles was studied. Better reusability was obtained by using Ir layers prepared at a high growth temperature, 1150 °C, which had a stable surface morphology in the multiple CVD cycles. Multilayer graphene islands were observed in the graphene films grown in the multiple CVD cycles, which was attributed to the carbon atoms dissolved during the previous CVD cycle. A method combining annealing, quenching, and oxygen plasma etching was proposed to remove the residual carbon atoms in the Ir layers. We succeeded in growing uniform monolayer graphene films in the multiple CVD cycles using the same Ir(111)/α-Al2O3(0001) substrate.

By creating nanoscale pores in a layer of graphene, it could be used as an effective separation membrane due to its chemical and mechanical stability, its flexibility and, most importantly, its one-atom thickness. Theoretical studies have indicated that the performance of such membranes should be superior to state-of-the-art polymer-based filtration membranes, and experimental studies have recently begun to explore their potential. Here, we show that single-layer porous graphene can be used as a desalination membrane. Nanometre-sized pores are created in a graphene monolayer using an oxygen plasma etching process, which allows the size of the pores to be tuned. The resulting membranes exhibit a salt rejection rate of nearly 100% and rapid water transport. In particular, water fluxes of up to 10(6) g m(-2) s(-1) at 40 °C were measured using pressure difference as a driving force, while water fluxes measured using osmotic pressure as a driving force did not exceed 70 g m(-2) s(-1) atm(-1).

Mass production of heat radiation devices requires for fine stamping of micro-textured patterns in the order of micro-meters in dimension onto the sheet product. In this duplication of micro-textured patterns, an original mother micro-pattern in the convex type has to be transferred onto the metallic sheet in the concave type with sufficient accuracy. The authors have proposed a micro texturing of original micro patterns onto the DLC coated mother die-and mold-unit. Once this unit is inserted and fixed in the stiff cassette die-set, the CNC-controlled stamping system works well for progressive stamping process to duplicate the original micro-patterns onto aluminum sheet. In the present paper, two kinds of motion in the stamper were designed to investigate the effect of loading and unloading sequences on the geometric accuracy in micro-texturing. Both the macroscopic and microscopic plastic deformations were described by SEM observation. First, high density oxygen plasma etching method was introduced to explain how to fabricate the micro-textured DLC-die unit. The constant-load motion control was employed as a normal motion in CNC-stamping to describe the microscopic metal flow by piercing the DLC micro-punch into the aluminum sheet. Deep micro-cavities with 3.5x3.5x3 μm3were successfully formed by application of high pressure in stamping. The pulse-wise motion control was further used to improve the geometric accuracy in the present duplication of original micro-texturing pattern onto the aluminum sheet. Owing to the incremental loading in this motion control, the micro-friction was significantly reduced to activate the microscopic metal flow in formation of micro-cavities.

Oxygen plasma etching was used to treat silk fibroin (SF). The plasma exposure removed a significant amount of SF but left behind most surface properties close to their original state. However, nano-indenter measurements revealed a substantial increase in surface modulus of swollen SF from 62 to 500kPa. This allowed oxygen plasma etching as a potential tool to investigate the impact of surface stiffness on cell-substrate interaction. Mouse fibroblasts (L929) and human mesenchymal stem cells (hMSC) were employed as distinct model cases. In vitro results revealed that the increased stiffness of plasma-treated SF affected only L929 adhesion, not hMSC. L929 cell attachment and spreading were better on the stiffer surface than the untreated surface, while hMSC could spread well on all SF surfaces.

We report first-principles molecular dynamics calculations combined with rare events sampling techniques that clarify atom-scale mechanisms of oxygen plasma etching of graphene. The obtained reaction pathways and associated free-energy landscapes show that the etching proceeds near vacancies via a two-step mechanism, formation of precursor lactone structures and the subsequent exclusive CO2 desorption. We find that atomic oxygen among the plasma components is most efficient for etching, providing a guidline in tuning the plasma conditions.

This paper reports a simple and scalable colloidal templating technology for fabricating wafer-scale periodic plasmonic nanodimple arrays with tunable nanostructures. A double-layer, non-close-packed colloidal crystal–polymer nanocomposite created by a spin-coating technique is used as structural template in a simple oxygen plasma etching process to fabricate periodic arrays of nanodimples. The resulting plasmonic arrays can sense a small dielectric refractive index change of ∼0.008, and they exhibit high SPR sensitivity of up to ∼520 nm per refractive index unit. The experimental plasmonic performance of the nanodimple arrays matches with the numerical simulations using a finite-difference time-domain model.

A submicron (280-nm), thin (3-nm) and transferrable graphene oxide grating layer is implemented for the first time by interference lithography, oxygen plasma etching, and PMMA-assisted transfer approach. The diffraction efficiency is measured to be only 4.98×10−7.

Screen-printed carbon electrodes (SPCEs) were selectively etched by oxygen plasma. The coefficient of variance (CV) of inter-electrode reproducibility was reduced from 21.6 to 4.6. Studies of the surface by color-level-indexing histogram analysis, scanning electronic microscopy (SEM) and resistance revealed that the inter-electrode reproducibility correlated with complete etching of the resin binder from the SPCE surface. The quality of the electrode was differentiated by this color level index analysis. This technique has great potential for application in on-line quality control of the SPCE plasma-treating process when integrated with suitable image processing software.

Lateral force microscopy has been employed to investigate the frictional behaviour of atomic vacancies on the graphite surface. Such a study was only made possible by the controlled expansion of originally single-atom vacancies into multiatom vacancies, employing oxygen plasma etching for this purpose. Enhanced friction was observed on the vacancy regions compared with pristine areas of graphite, the origin of which is examined and discussed.

Cellular micropatterning has become an important tool to precisely design cell-to-substrate attachment for cell biology studies, tissue engineering, cell-based biosensors, biological assays, and dr...

Mg-doped InZnO (MIZO) films were prepared by sol-gel method. The surface of the films was treated by oxygen plasma. Pt was then deposited on O 2 -treated films to form MIZO/Pt Schottky diode. The I-V properties of this structure were studied under different oxygen plasma treatment conditions. The experimental results show that oxygen plasma treatment can improve the Schottky properties by minimizing the surface adsorbates and subsurface defects of MIZO films.

Recent developments in the chemistry of organosilicon polymers for use as oxygen plasma-resistant imaging materials in microlithography are reviewed. Various classes of resists, grouped according to molecular structure, are described with special emphasis on properties critical in microlithographic applications. In addition, several silylation schemes involving selective silylation of a non-silicon-containing resist material following patternwise exposure to actinic radiation are also described.

Water tree morphology as revealed by oxygen plasma etching of water trees in low-density polyethylene is reported. Water trees sectioned by freeze fracturing are found to be virtually invisible until treated by plasma etching. Etching attack is localized and produces either a pitted or a channeled structure, depending on the water tree growth conditions. The spatial distribution of the pits or channels is reminiscent of water tree void distribution. Secondary electron photomicrographs of trees grown under varied conditions are presented. >

A novel ZnO-FTO heterostructure nanotube array was produced by combining a chemical solution process with oxygen-plasma etching. In this approach, presynthesized ZnO nanorod arrays act as templates, and FTO nanoparticles are deposited onto the ZnO nanorods by a simple spray pyrolysis method. X-ray photoelectron spectroscopy analysis demonstrated that the oxygen-plasma treatment decreased the O(2-)/OH(-) concentration ratio, resulting in dissociation of the Zn-O bonds and the outward diffusion of Zn cations to form an interior hollow, which is related to the formation of the hydroxyl functional group, Sn-OH, at the FTO surface. An etching evolution mechanism of the ZnO-FTO nanotubes via oxygen plasma was tentatively proposed in this study. Time-dependent photocurrent (I-T) measurements under ON-OFF cycles of UV illumination confirm that the 20-min etched sample exhibits a rectified photoresponse characteristic and a dark current increased by about 3 orders of magnitude over that of the unetched sample, which is attributed to the increased carrier concentration created at the surface conductive layer. This investigation offers an alternative selective etching method to lay the framework for nanoscale three-dimensional electrodes for solar-cell applications.

The application of the plasma etching method to determine the size distribution of polybutadiene particles in high impact polystyrene is described

Fruhere Hypothesen uber einige Besonderheiten des Atzens von Poly(vinylalkohol) (PVAL) im Sauerstoffplasma wurden bestatigt. Erstens wird beim O2-RIE von Poly(vinylalkohol) im Unterschied zum Plasmaatzmodus kein Abfall der Atzgeschwindigkeit mit steigendem Schichtabtrag beobachtet. Zweitens ist die Aktivierungsenergie beim Plasmaatzen von Poly(vinylbutyral) im Unterschied zum PVAL unabhangig vom Schichtabtrag. Diese experimentellen Ergebnisse sowie einige Literaturangaben bestatigen, das sich auf PVAL-Schichten im Sauerstoffplasma eine dicke „K-Schicht” bildet. Im Polymervolumen ablaufende Degradationsprozesse unter dieser „K-Schicht” sind hauptsachlich fur den Abbau dunner Schichten aus PVAL im Sauerstoffplasma verantwortlich. Earlier hypotheses on particularities of oxygen plasma etching of poly(vinyl alcohol) (PVAL) are confirmed. Firstly, in difference to etching under O2-RIE conditions a decrease of the etching rate during polymer removal does not occur. Secondly, the activation energy of plasma etching of poly(vinyl butyral) in contrast to PVAL does not depend on the polymer degradation process. These experimental results together with literature data confirm the assumption of a relatively thick “K-layer” on the polymer surface in oxygen plasmas. Degradation processes take place in the bulk polymer below this “K-layers”. They are responsible for removal of the PVAL layers.

Fur das Atzen von Poly(vinylalkohol) im Sauerstoffplasma wurden einige Besonderheiten festgestellt. Die Kinetik des Schichtabtrags last den Schlus zu, das eine relativ dicke, aber wenig atzresistente „K-Schicht” im Verlauf des Plasmaatzens gebildet wird. Sie besteht moglicherweise zum Teil aus vernetzten Makromolekulen, konjugierten Doppelbindungen innerhalb der Polymerkette durch Dehydratisierung bzw. aus graphitischem und anoxidiertem Kohlenstoff. Aus der Temperaturabhangigkeit der Atzgeschwindigkeit folgt die Annahme von zwei konkurrierenden Reaktionen, deren eine zum Schichtabbau, die andere dagegen zu weiterer Polymervernetzung fuhrt. At the investigation of oxygen plasma etching of poly(vinyl alcohol) some peculiarities have been found. Based on the etching kinetics, the formation of a thick, but not very stable „K-layer” is assumed. The molecular structure of this modified layer may consist of some sections of conjugated double bonds within the polymer chain, graphitic and oxidized carbon, and crosslinked chains. From the unusual temperature dependence of the etching rate the existence of two competitive reactions is concluded. One reaction leads to degradation, the other to crosslinking of the macromolecules.

In this paper, we propose a multiple cell treatment array with high-density arrayed micro-orifice having an individually accessible microchannel and electrodes. More than 10000 micro-orifices with the diameter of 2 mum can be simultaneously fabricated by Single-Mask inclined UV photolithography for embedded network (SIMPLE) process with the oxygen plasma etching. More than 200 living cells immobilized at the arrayed micro-orifices were permeabilized by electroporation and allowed to uptake an foreign impermeant substance.

The technology of selective oxygen plasma etching is presented. It enables the evaluation of the state of pigment dispersion, as well as the distribution of other solid particles that are added in pigmented coatings for various functional purposes. The technology is based on the selective interaction of reactive gaseous particles from oxygen plasma with the pigment-polymer composite. In our case, we wanted to etch the polymer matrix while leaving the particles untouched. Scanning electron microscope images of the effects of exposing the composite to oxygen plasma are presented.