Initial stages of silicate growth on and oxidation of graphite: A model for composites

The initial stages of silicate growth on graphite are characterized with atomic force microscopy. The morphological development indicates that decomposition of tetra ethyloxysilane at low pressure produces films of 3 nm clusters located at undercoordinated carbon sites. Clusters eventually cover the surface, at which point a second layer grows. In higher pressure deposition multiple layers of clusters grow simultaneously. A comparison of the oxidation behavior of surfaces with defects completely and incompletely terminated with SiOx shows that edge recession is the primary oxidation mechanism and that the site specificity of SiOx is effective in inhibiting oxidation.

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Novel Zirconia Surface Treatments for Enhanced Osseointegration: Laboratory Characterization

International Journal of Dentistry ◽

10.1155/2014/203940 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 7

Author(s):

Ola H. Ewais ◽

Fayza Al Abbassy ◽

Mona M. Ghoneim ◽

Moustafa N. Aboushelib

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Surface Hardness ◽

Surface Characteristics ◽

Low Pressure ◽

Surface Treatments ◽

Control Surface ◽

Force Microscopy ◽

Atomic Force ◽

Zirconia Implants

Purpose. The aim of this study was to evaluate three novel surface treatments intended to improve osseointegration of zirconia implants: selective infiltration etching treatment (SIE), fusion sputtering (FS), and low pressure particle abrasion (LPPA). The effects of surface treatments on roughness, topography, hardness, and porosity of implants were also assessed.Materials and Methods. 45 zirconia discs (19 mm in diameter × 3 mm in thickness) received 3 different surface treatments: selective infiltration etching, low pressure particle abrasion with 30 µm alumina, and fusion sputtering while nontreated surface served as control. Surface roughness was evaluated quantitatively using profilometery, porosity was evaluated using mercury prosimetry, and Vickers microhardness was used to assess surface hardness. Surface topography was analyzed using scanning and atomic force microscopy (α=0.05).Results. There were significant differences between all groups regarding surface roughness (F=1678,P<0.001), porosity (F=3278,P<0.001), and hardness (F=1106.158,P<0.001). Scanning and atomic force microscopy revealed a nanoporous surface characteristic of SIE, and FS resulted in the creation of surface microbeads, while LPPA resulted in limited abrasion of the surface.Conclusion. Within the limitations of the study, changes in surface characteristics and topography of zirconia implants have been observed after different surface treatment approaches. Thus possibilities for enhanced osseointegration could be additionally offered.

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Surface Morphology of 4H-SiC after Thermal Oxidation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.963.180 ◽

2019 ◽

Vol 963 ◽

pp. 180-183 ◽

Cited By ~ 1

Author(s):

Judith Woerle ◽

Vito Šimonka ◽

Elisabeth Müller ◽

Andreas Hössinger ◽

Hans Sigg ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Atomic Force Microscopy ◽

Thermal Oxidation ◽

Oxidation Behavior ◽

Planar Surface ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Oxidation Model

Step-controlled growth of 4H-SiC epitaxial layers leads to the formation of a step-bunched morphology along the surface with larger macrosteps, composed of smaller microsteps of several Si-C bilayer heights. As thermal oxidation is an orientation-dependent process, a multi-faceted surface is expected to exhibit a different oxidation behavior compared to a perfectly planar surface. In this work, step-bunched surfaces after oxidation are investigated by high-resolution atomic force microscopy (HR-AFM) and transmission electron microscopy (TEM) indicating a morphological change in the early stages of thermal oxidation. An orientation-dependent oxidation model is used to correctly describe variations of the oxide thicknesses at isolated macrosteps.

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Characterization of the low-pressure chemical vapor deposition grown rugged polysilicon surface using atomic force microscopy

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.580507 ◽

1997 ◽

Vol 15 (3) ◽

pp. 1007-1013 ◽

Cited By ~ 21

Author(s):

Yale E. Strausser ◽

Michael Schroth ◽

John J. Sweeney III

Keyword(s):

Atomic Force Microscopy ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Low Pressure ◽

Force Microscopy ◽

Atomic Force ◽

Pressure Chemical

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Local Anodic Oxidation of Phosporous-Implanted 4H-SiC by Atomic Force Microscopy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.905 ◽

2012 ◽

Vol 717-720 ◽

pp. 905-908 ◽

Cited By ~ 2

Author(s):

Jung Ho Lee ◽

Jung Jun Ahn ◽

Anders Hallén ◽

Carl Mikael Zetterling ◽

Sang Mo Koo

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Oxidation Behavior ◽

Annealing Process ◽

Applied Bias ◽

Force Microscopy ◽

Atomic Force ◽

Local Oxidation ◽

Local Anodic Oxidation ◽

Post Implantation

In this work, local oxidation behavior in phosphorous ion-implanted 4H-SiC has been investigated by using atomic force microscopy (AFM). The AFM-local oxidation (LO) has been performed on the implanted samples, with and without activation anneal, using varying applied bias (15/20/25 V). It has been clearly shown that the post-implantation annealing process at 1650 oC has a great impact on the local oxidation rate by electrically activating the dopants and by modulating the surface roughness. In addition, the composition of resulting oxides changes depending on the doping level of SiC surfaces.

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