scholarly journals Topographical and Physicochemical Contrast in Photopatterned SU-8 Films for Microfabrication of Multilayer Structures

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
L. Salazar Alarcón ◽  
E. D. Martínez ◽  
L. M. Rodríguez ◽  
H. Pastoriza
Keyword(s):  
Multilayer Structures ◽  
Height Profile ◽  
Rutherford Back Scattering ◽  
Interface Diffusion ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Back Scattering ◽  
Surface Profiles ◽  
Photolithography Process ◽  
Film Solubility

During SU-8 standard photolithography process, a patterned topography is formed with a characteristic height profile produced by the different shrinkage of the UV exposed and masked regions. We study the change of wettability, film solubility, and topographic modifications on SU-8 films of different thicknesses and show its relevance in the formation of spinning-flow arrays on top layers made from positive photoresists. Also, considerable contrast in film solubility and surface energy as observed from contact angle measurements is produced. Interface diffusion of the photoresists was also observed and followed by Rutherford Back Scattering. We discuss the derivations of the mentioned effects concerning the limitations to multilayered microfabrication processes and possibilities to take advantage of the surface profiles obtained.

Nanostructured Polymer Brushes With Reversibly Changing Properties

2002 ◽  
Vol 727 ◽  
Author(s):  
Denys Usov ◽  
Manfred Stamm ◽  
Sergiy Minko ◽  
Christian Froeck ◽  
Andreas Scholl ◽  
...  
Keyword(s):  
Polymer Brushes ◽  
Phase Segregation ◽  
Water Contact ◽  
Angle Measurements ◽  
Nanostructured Polymer ◽  
Contact Angle Measurements ◽  
Vertical Segregation ◽  
Oxygen Plasma Etching ◽  
Grafting From ◽  
Photoemission Electron

AbstractWe investigated the interplay between different mechanisms of the lateral and vertical segregation in the synthesized via “grafting from” approach symmetric A/B (where A and B are poly(styrene-co-2,3,4,5,6-pentafluorostyrene) and poly(methylmethacrylate), respectively) polymer brushes upon exposure to different solvents. We used X-ray photoemission electron spectroscopy and microscopy (X-PEEM), AFM, water contact angle measurements, and oxygen plasma etching to study morphology of the brushes. The ripple morphology after toluene (nonselective solvent) revealed elongated lamellar-like domains of A and B polymers alternating across the surface. The dimple-A morphology consisting of round clusters of the polymer A was observed after acetone (selective solvent for B). The top layer was enriched with the polymer B showing that the brush underwent both the lateral and vertical phase segregation. A qualitative agreement with predictions of SCF theory was found.

Wrinkling Poly(trimethylene 2,5-Furanoate) Free-standing Films: Nanostructure Formation and Physical Properties

2020 ◽  
Author(s):  
Michelina Soccio ◽  
Nadia Lotti ◽  
Andrea Munari ◽  
Esther Rebollar ◽  
Daniel E Martínez-Tong
Keyword(s):  
Irradiation Time ◽  
Polymer Surface ◽  
Laser Source ◽  
Free Standing ◽  
Force Microscopy ◽  
Nanostructure Formation ◽  
Physicochemical Changes ◽  
Angle Measurements ◽  
Atomic Force ◽  
Contact Angle Measurements

<p>Nanostructured wrinkles were developed on fully bio-based poly(trimethylene furanoate) (PTF) films by using the technique of Laser Induced Periodic Surface Structures (LIPSS). We investigated the effect of irradiation time on wrinkle formation using an UV pulsed laser source, at a fluence of 8 mJ/cm2. It was found that the pulse range between 600 and 4800 pulses allowed formation of periodic nanometric ripples. The nanostructured surface was studied using a combined macro- and nanoscale approach. We evaluated possible physicochemical changes taking place on the polymer surface after irradiation by infrared spectroscopy, contact angle measurements and atomic force microscopy. The macroscopic physicochemical properties of PTF showed almost no changes after nanostructure formation, differently from the results previously found for the terephthalic counterparts, as poly(ethyleneterephthalate), PET, and poly(trimethyleneterephthalate), PTT. The surface mechanical properties of the nanostructured PTF were found to be improved, as evidenced by nanomechanical force spectroscopy measurements. In particular, an increased Young’s modulus and higher stiffness for the nanostructured sample were measured. <br></p>

scholarly journals Adhesion Studies during Generative Hybridization of Textile-Reinforced Thermoplastic Composites via Additive Manufacturing

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3888
Author(s):  
Johanna Maier ◽  
Christian Vogel ◽  
Tobias Lebelt ◽  
Vinzenz Geske ◽  
Thomas Behnisch ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Polyamide 6 ◽  
Thermoplastic Composites ◽  
Efficient Production ◽  
Angle Measurements ◽  
Small Series ◽  
Contact Angle Measurements ◽  
Static Tensile ◽  
Pre Treatment ◽  
Manufacturing Technologies

Generative hybridization enables the efficient production of lightweight structures by combining classic manufacturing processes with additive manufacturing technologies. This type of functionalization process allows components with high geometric complexity and high mechanical properties to be produced efficiently in small series without the need for additional molds. In this study, hybrid specimens were generated by additively depositing PA6 (polyamide 6) via fused layer modeling (FLM) onto continuous woven fiber GF/PA6 (glass fiber/polyamide 6) flat preforms. Specifically, the effects of surface pre-treatment and process-induced surface interactions were investigated using optical microscopy for contact angle measurements as well as laser profilometry and thermal analytics. The bonding characteristic at the interface was evaluated via quasi-static tensile pull-off tests. Results indicate that both the bond strength and corresponding failure type vary with pre-treatment settings and process parameters during generative hybridization. It is shown that both the base substrate temperature and the FLM nozzle distance have a significant influence on the adhesive tensile strength. In particular, it can be seen that surface activation by plasma can significantly improve the specific adhesion in generative hybridization.

scholarly journals Epoxy/alumina composite coating on welded steel 316L with excellent wear and anticorrosion properties

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maryama Hammi ◽  
Younes Ziat ◽  
Zakaryaa Zarhri ◽  
Charaf Laghlimi ◽  
Abdelaziz Moutcine
Keyword(s):  
Electrochemical Behaviour ◽  
Sem Analysis ◽  
Water Contact ◽  
Welded Steel ◽  
Melted Zone ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Alumina Composite ◽  
The Cost ◽  
Good Contrast

AbstractThe main purpose of this study is to elaborate anticorrosive coatings for the welded steel 316L, since this later is widely used in industrial field. Hence, within this work we have studied the electrochemical behaviour of different zones of the welded steel 316 in 1 M HCl media. The macrography study of the welded steel has revealed the different areas with a good contrast. We have stated three different zones, namely; melted zone (MZ), heat affected zone (HAZ) and base metal zone (BM). Impedance studies on welded steel 316L were conducted in 1 M HCl solution, coating of Epoxy/Alumina composite was applied on different zones, in order to reveal the anti-corrosion efficiency in each zone. Scanning electron microscopy (SEM) analysis was undertaken in order to check how far the used coating in such aggressive media protects the studied zones and these findings were assessed by water contact angle measurements. The choice of this coating is based on the cost and the safety. We concluded that the Epoxy/Alumina composite has a good protecting effect regarding welded steel in aggressive media.

Wettability Determination by Equilibrium Contact Angle Measurements: Reservoir Rock- Connate Water System With Injection of CO2

2012 ◽  
Author(s):  
Narjes Shojaikaveh ◽  
Cas Berentsen ◽  
Susanne Eva Johanne Rudolph-Floter ◽  
Karl Heinz Wolf ◽  
William Richard Rossen
Keyword(s):  
Contact Angle ◽  
Water System ◽  
Reservoir Rock ◽  
Equilibrium Contact Angle ◽  
Connate Water ◽  
Angle Measurements ◽  
Contact Angle Measurements

Surface Wettability Enhances Osteoblast Adhesion on Silicon-Substituted Hydroxyapatite Thin Films

2007 ◽  
Vol 330-332 ◽  
pp. 877-880 ◽  
Author(s):  
E.S. Thian ◽  
J. Huang ◽  
Serena Best ◽  
Zoe H. Barber ◽  
William Bonfield
Keyword(s):  
Thin Films ◽  
Contact Angle ◽  
Actin Filaments ◽  
Culture Study ◽  
Cell Culture Study ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Osteoblast Adhesion ◽  
Lower Contact

Crystalline hydroxyapatite (HA) and 0.8 wt.% silicon-substituted HA (SiHA) thin films were produced using magnetron co-sputtering. These films were subjected to contact angle measurements and in vitro cell culture study using human osteoblast-like (HOB) cells. A wettability study showed that SiHA has a lower contact angle, and thus is more hydrophilic in nature, as compared to HA. Consequently, enhanced cell growth was observed on SiHA at all time-points. Furthermore, distinct and well-developed actin filaments could be seen within HOB cells on SiHA. Thus, this work demonstrated that the surface properties of the coating may be modified by the substitution of Si into the HA structure.

Carbon Nanotubes Grown on Metallic Wires by Cold Plasma Technique

2002 ◽  
Vol 737 ◽  
Author(s):  
D. Sarangi ◽  
A. Karimi
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Growth Conditions ◽  
Effect Of Temperature ◽  
Rutherford Back Scattering ◽  
Novel Approach ◽  
Transmission Electron ◽  
Back Scattering ◽  
Metallic Wires ◽  
Metal Wires

ABSTRACTCarbon nanotubes on metallic wires may be act as electrode for the field emission (FE) luminescent devices. Growing nanotubes on metallic wires with controlled density, length and alignment are challenging issues for this kind of devices. We, in the present investigation grow carbon nanotubes directly on the metal wires by a powerful but simple technique. A novel approach has been proposed to align nanotubes during growth. Methane, acetylene and dimethylamine have been used as source gases. With the same growth conditions (viz. pressure, growth temperature and plasma) methane does not produce any nanotube but nanotubes grown with dimethylamine show shorter length and radius than acetylene. The effect of temperature to control the radius, time to control the density, plasma conditions to align the nanotubes has been focused. Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Rutherford Back Scattering (RBS) are used to characterize the nanotubes.

Compositional Effects on the Degradation of PVD-Tisin

1997 ◽  
Vol 473 ◽  
Author(s):  
W. F. McArthur ◽  
F. Deng ◽  
K. Ring ◽  
P. M. Pattison ◽  
K. L. Kavanagh
Keyword(s):  
Phase Separation ◽  
Silicon Nitride ◽  
Electron Diffraction ◽  
Titanium Nitride ◽  
Amorphous Matrix ◽  
Barrier Material ◽  
Rutherford Back Scattering ◽  
Phase Line ◽  
Back Scattering ◽  
Target Ratio

ABSTRACTPVD-TixSiyNz films formed by reactive RF-magnetron co-sputtering of Ti and Si in Ar/N2 are evaluated as a diffusion barrier between Cu and Si. A complete range of compositions are obtained by Ti targets inlaid with Si. Film composition is controlled by the target ratio of titanium to silicon and N2 partial pressure. Electrical results versus thermal history for films of∼6–18% Si as well as the composition and microstructure as determined by Rutherford back scattering (RBS), TEM and electron diffraction are reported. These films are an amorphous matrix with imbedded nanocrystals of titanium nitride as-deposited and undergo phase separation to yield titanium nitride and silicon nitride after a 1000°C anneal. As-deposited compositions which lie above the TiN-Si3N4 phase line yield crystals of TiN. Compositions below the TiN-Si3N4 phase line yield crystals of Ti2N. Bulk resistivity as-deposited (<400μω-cm) is acceptable for use as a contact liner/barrier material and improves with annealing. Si pn-diodes metallized with 20nm Ti40Si15N45 and Cu show no significant increase in reverse leakage current at anneal temperatures below 700°C.

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