Argon Plasma Induced Surface Modifications For Resistless Patterning Of Aluminium Films

ABSTRACTArgon plasma exposure has been used to induce surface chemical modification of aluminium thin films, causing a drastic change in etch rate in standard HNO3/CH3COOH/H3PO4 etchant. The inhibition period was found to increase with power and Ar plasma exposure time. Auger electron and x-ray photoelectron spectroscopies have indicated formation of an aluminium fluoride (AlF3) surface layer due to fluorine contamination originating from the residue left in the plasma chamber during CF4 processing. The high etch selectivity between unexposed and argon plasma exposed regions has been exploited as a new technique for resistless patterning of aluminium.

Download Full-text

Surface Chemical Modification and Analysis of Carbon Fibers - The Key to Novel Composites

MRS Proceedings ◽

10.1557/proc-270-79 ◽

1992 ◽

Vol 270 ◽

Cited By ~ 7

Author(s):

Peter M.A. Sherwood

Keyword(s):

Carbon Fibers ◽

Photoelectron Spectroscopy ◽

Fiber Surface ◽

Surface Chemical ◽

Plasma Oxidation ◽

X Ray ◽

Chemical Effects ◽

The Matrix ◽

Physical And Chemical ◽

Surface Chemical Modification

ABSTRACTCarbon fibers are finding increasing application in making various composites with special properties. It is found that such composites have properties that can be markedly effected by the carbon fiber surface. The effects of surface modification by electrochemical and plasma oxidation is discussed and the surface chemical changes described. The interaction of the matrix with the fiber surface is a subtle mixture of physical and chemical effects. The paper discusses work in the author's laboratory using surface studies with core and valence band X-ray photoelectron spectroscopy (XPS) and other techniques.

Download Full-text

Biocompatibility of Cyclopropylamine-Based Plasma Polymers Deposited at Sub-Atmospheric Pressure on Poly (ε-caprolactone) Nanofiber Meshes

Nanomaterials ◽

10.3390/nano9091215 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1215 ◽

Cited By ~ 4

Author(s):

Ke Vin Chan ◽

Mahtab Asadian ◽

Iuliia Onyshchenko ◽

Heidi Declercq ◽

Rino Morent ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Atmospheric Pressure ◽

Cellular Response ◽

Considerable Effect ◽

Surface Chemical ◽

Plasma Exposure ◽

Plasma Polymers ◽

X Ray ◽

Surface Chemical Composition ◽

Cell Adhesion And Proliferation

In this work, cyclopropylamine (CPA) monomer was plasma-polymerized on poly (ε-caprolactone) nanofiber meshes using various deposition durations to obtain amine-rich surfaces in an effort to improve the cellular response of the meshes. Scanning electron microscopy and X-ray photoelectron spectroscopy (XPS) were used to investigate the surface morphology and surface chemical composition of the PCL samples, respectively. The measured coating thickness was found to linearly increase with deposition duration at a deposition rate of 0.465 nm/s. XPS analysis revealed that plasma exposure time had a considerable effect on the surface N/C and O/C ratio as well as on amino grafting efficiency and amino selectivity. In addition, cell studies showed that cell adhesion and proliferation significantly improved for all coated samples.

Download Full-text

Techniques for cryoultramicrotomy of propane jet frozen biological samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014292x ◽

1986 ◽

Vol 44 ◽

pp. 260-261

Author(s):

B. Craig ◽

L. Hawkey ◽

A. LeFurgey

Keyword(s):

Freeze Fracture ◽

Freeze Substitution ◽

Heart Cells ◽

Crystal Formation ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission ◽

Chick Heart ◽

Embryonic Chick Heart ◽

A New Technique

Ultra-rapid freezing followed by cryoultramicrotomy is essential for the preservation of diffusible elements in situ within cells prior to scanning transmission electron microscopy and quantitative energy dispersive x-ray microanalysis. For cells or tissue fragments in suspension and for monolayer cell cultures, propane jet freezing provides cooling rates greater than 30,000°C/sec with regions up to 40μm in thickness free of significant ice crystal formation. While this method of freezing has frequently been applied prior to freeze fracture or freeze substitution, it has not been widely utilized prior to cryoultramicrotomy and subsequent x-ray microanalytical studies. This report describes methods devised in our laboratory for cryosectioning of propane jet frozen kidney proximal tubule suspensions and cultured embryonic chick heart cells, in particular a new technique for mounting frozen suspension specimens for sectioning. The techniques utilize the same specimen supports and sample holders as those used for freeze fracture and freeze substitution and should be generally applicable to any cell suspension or culture preparation.

Download Full-text