scholarly journals Monitoring of the morphologic reconstruction of deposited ablation products in laser irradiation of silicon

2008 ◽  
Vol 40 (1) ◽  
pp. 69-78 ◽  
Author(s):  
M. Vlasova ◽  
Márquez Aguilar ◽  
M.C. Reséndiz-González ◽  
M. Kakazey ◽  
V. Stetsenko ◽  
...  
Keyword(s):  
Laser Irradiation ◽  
Heating Temperature ◽  
Composite Films ◽  
Target Surface ◽  
Oxygen Impurity ◽  
Irradiation Channel ◽  
Force Microscopy ◽  
Atomic Force ◽  
Gaseous Atmospheres ◽  
Main Components

Using electron microscopy, atomic force microscopy, X-ray microanalysis, and IR spectroscopy, it was established that, in the regime of continuous laser irradiation of silicon at P = 170 W in different gaseous atmospheres with an oxygen impurity, SiOx composite films with a complex morphology form. The main components of ablation products are clusters that form during flight of ablation products and as a result of separation of SiOx-clusters from the zone of the irradiation channel. The roughness and density of the films depend on the heating temperature of the target surface and the type of deposited clusters.

scholarly journals Monitoring of the morphologic reconstruction of deposited ablation products in laser irradiation of silicon

2008 ◽  
Vol 40 (1) ◽  
pp. 69-78
Author(s):  
M. Vlasova ◽  
Márquez Aguilar ◽  
M.C. Reséndiz-González ◽  
M. Kakazey ◽  
V. Stetsenko ◽  
...  
Keyword(s):  
Laser Irradiation ◽  
Heating Temperature ◽  
Composite Films ◽  
Target Surface ◽  
Oxygen Impurity ◽  
Irradiation Channel ◽  
Force Microscopy ◽  
Atomic Force ◽  
Gaseous Atmospheres ◽  
Main Components

Using electron microscopy, atomic force microscopy, X-ray microanalysis, and IR spectroscopy, it was established that, in the regime of continuous laser irradiation of silicon at P = 170 W in different gaseous atmospheres with an oxygen impurity, SiOx composite films with a complex morphology form. The main components of ablation products are clusters that form during flight of ablation products and as a result of separation of SiOx-clusters from the zone of the irradiation channel. The roughness and density of the films depend on the heating temperature of the target surface and the type of deposited clusters.

Preparation of Cellulose Nanofibrils by High-Pressure Homogenizer and Zein Composite Films

2013 ◽  
Vol 829 ◽  
pp. 534-538 ◽  
Author(s):  
Alireza Shakeri ◽  
Sattar Radmanesh
Keyword(s):  
Atomic Force Microscopy ◽  
High Pressure ◽  
Food Packaging ◽  
Cellulose Nanofibrils ◽  
Composite Films ◽  
Average Diameter ◽  
Nanocomposite Films ◽  
Force Microscopy ◽  
Atomic Force ◽  
High Pressure Homogenizer

Cellulose nanofibrils ( NF ) have several advantages such as biodegradability and safety toward human health. Zein is a biodegradable polymer with potential use in food packaging applications. It appears that polymer nanocomposites are one of the most promising applications of zein films. Cellulose NF were prepared from starting material Microcrystalline cellulose (MCC) by an application of a high-pressure homogenizer at 20,000 psi and treatment consisting of 15 passes. Methods such as atomic force microscopy were used for confirmation of nanoscale size production of cellulose. The average diameter 45 nm were observed. Zeincellulose NF nanocomposite films were prepared by casting ethanol suspensions of Zein with different amounts of cellulose NF in the 0% to 5%wt. The nanocomposites were characterized by using Fourier transform infrared spectroscopy ( FTIR ), Atomic force microscopy ( AFM ) and X-ray diffraction ( XRD ) analysis. From the FTIR spectra the various groups present in the Zein blend were monitored. The homogeneity, morphology and crystallinity of the blends were ascertained from the AFM and XRD data, respectively. The thermal resistant of the zein nanocomposite films improved as the nanocellulose content increased. These obtained materials are transparent, flexible and present significantly better physical properties than the corresponding unfilled Zein films.

MICROCRACKS IN ~ 100 MeV Si7+-ION-IRRADIATED p-SILICON SURFACES

2004 ◽  
Vol 11 (03) ◽  
pp. 265-269
Author(s):  
O. P. SINHA ◽  
P. C. SRIVASTAVA ◽  
V. GANESAN
Keyword(s):  
Atomic Force Microscopy ◽  
Surface Morphology ◽  
Target Surface ◽  
Silicon Surfaces ◽  
Force Microscopy ◽  
Atomic Force ◽  
Induced Stress

The p-silicon surfaces have been irradiated with ~ 100 MeV Si 7+ions to a fluence of 2.2×1013 ions cm -2, and surface morphology has been studied with atomic force microscopy (AFM). Interesting features of cracks of ~ 47 nm in depth and ~ 103 nm in width on the irradiated surfaces have been observed. The observed features seemed to have been caused by the irradiation-induced stress in the irradiated regions of the target surface.

scholarly journals Synthesis and Characterization of PLA-Micro-structured Hydroxyapatite Composite Films

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 274 ◽  
Author(s):  
Andreea Madalina Pandele ◽  
Andreea Constantinescu ◽  
Ionut Cristian Radu ◽  
Florin Miculescu ◽  
Stefan Ioan Voicu ◽  
...  
Keyword(s):  
Composite Films ◽  
Synthesis Method ◽  
Polymer Chains ◽  
Force Microscopy ◽  
Degradation Temperature ◽  
Atomic Force ◽  
Hydroxyapatite Composite ◽  
Ft Ir ◽  
Ir And Raman

This article presents a facile synthesis method used to obtain new composite films based on polylactic acid and micro-structured hydroxyapatite particles. The composite films were synthesized starting from a polymeric solution in chloroform (12 wt.%) in which various concentrations of hydroxyapatite (1, 2, and 4 wt.% related to polymer) were homogenously dispersed using ultrasonication followed by solvent evaporation. The synthesized composite films were morphologically (through SEM and atomic force microscopy (AFM)) and structurally (through FT-IR and Raman spectroscopy) characterized. The thermal behavior of the composite films was also determined. The SEM and AFM analyses showed the presence of micro-structured hydroxyapatite particles in the film’s structure, as well as changes in the surface morphology. There was a significant decrease in the crystallinity of the composite films compared to the pure polymer, this being explained by a decrease in the arrangement of the polymer chains and a concurrent increase in the degree of their clutter. The presence of hydroxyapatite crystals did not have a significant influence on the degradation temperature of the composite film.

Solvent-induced supramolecular assemblies of crown-substituted ruthenium phthalocyaninate: morphology of assemblies and non-linear optical properties

2009 ◽  
Vol 13 (01) ◽  
pp. 92-98 ◽  
Author(s):  
Antonina D. Grishina ◽  
Yulia G. Gorbunova ◽  
Victor I. Zolotarevsky ◽  
Larisa Ya. Pereshivko ◽  
Yulia Yu. Enakieva ◽  
...  
Keyword(s):  
Heating Temperature ◽  
Supramolecular Assemblies ◽  
Scanning Method ◽  
Force Microscopy ◽  
Atomic Force ◽  
Non Linear ◽  
Linear Optical Properties ◽  
Linear Optical ◽  
Complex Solutions ◽  
The Individual

The information concerning the architecture of supramolecular assemblies, which are composed of ruthenium(II) tetra-15-crown-5-phthalocyaninate with axially coordinated triethylenediamine molecules, has been obtained with the application of atomic force microscopy. The ensembles are formed in Ru ( II ) complex solutions in chloroform and tetrachloroethane. The number of molecules and their relative orientation in supramolecular assemblies were estimated in dependence of the solvent (chloroform, tetrachloroethane) and the heating temperature. Samples fabricated after heating of the Ru ( II ) complexes solution in tetrachloroethane formed stable supramolecular wires of 600 nm and more in length. The third-order non-linear optical characteristics of complexes in tetrachloroethane solution were studied by the z-scanning method. Molecular polarizability of the complex is about 4.5 × 10-32 esu. The polarizability attributed to one molecule increases by a factor of 3.6 when the individual molecule assembles into a supramolecular aggregate.

scholarly journals Laser irradiation of SiC-MoSi2 composite ceramics

2008 ◽  
Vol 40 (3) ◽  
pp. 271-281
Author(s):  
Marquez Aguilar ◽  
M. Vlasova ◽  
M.C. Reséndiz-González ◽  
M. Kakazey ◽  
Mayorga Cruz ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Laser Irradiation ◽  
Irradiation Time ◽  
Composite Ceramics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Ir Laser ◽  
Mosi2 Composite

The influence of continuous IR laser irradiation (? = 1064 nm, P = 240 mW) on SiC-MoSi2 composite ceramics was investigated by X-ray diffraction, electron microscopy, atomic force microscopy, and X-ray microanalysis. The irradiation of specimens was carried out in air. It was established that, due to heating of the surface under laser irradiation, oxidation of SiC and MoSi2 and sublimation of SiO (SiO2) and MoO3 take place. Depending on the content of the components in the ceramics and the irradiation time, SiO2 or MoO3 layers form on the surface or disappear from it. For a long irradiation time, the oxidation and cleaning of the surface (sublimation of oxides) are cyclic in character.

A Model for the Films Formation of Nb–Si–N Ternary Compound Deposited

2012 ◽  
Vol 476-478 ◽  
pp. 475-479 ◽  
Author(s):  
Yong Jun Jiang
Keyword(s):  
Film Formation ◽  
Composite Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nanoscale Structures ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Step Model ◽  
Si Content

By means of the reactive magnetron sputtering method, a series of Nb–Si–N composite films with different Si contents were deposited in an Ar, N2 and SiH4 mixture atmosphere. These films’ chemical composition, phase formation, microstructure and mechanical properties were characterized by the energy dispersive spectroscopy, X-ray diffraction, transmission electron microcopy, atomic force microscopy and nanoindentation. In the Nb–Si–N films, 3 distinct concentration regions have been observed depending on the Si content. Based on the three concentration regions, a three-step model is proposed for the film formation of the Nb–Si–N thin films. This model correlates nanoscale structures with macroscopic properties of the films.

scholarly journals Phosphate Modified Screen Printed Electrodes by LIFT Treatment for Glucose Detection

Biosensors ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 91 ◽  
Author(s):  
Francesco Milano ◽  
Livia Giotta ◽  
Daniela Chirizzi ◽  
Simos Papazoglou ◽  
Christina Kryou ◽  
...  
Keyword(s):  
Glassy Carbon ◽  
Glucose Sensor ◽  
Adsorbed Layer ◽  
Target Surface ◽  
Force Microscopy ◽  
Atomic Force ◽  
Screen Printed Electrodes ◽  
Forward Transfer ◽  
Glucose Electrooxidation ◽  
Screen Printed

The design of new materials as active layers is important for electrochemical sensor and biosensor development. Among the techniques for the modification and functionalization of electrodes, the laser induced forward transfer (LIFT) has emerged as a powerful physisorption method for the deposition of various materials (even labile materials like enzymes) that results in intimate and stable contact with target surface. In this work, Pt, Au, and glassy carbon screen printed electrodes (SPEs) treated by LIFT with phosphate buffer have been characterized by scanning electron microscopy and atomic force microscopy to reveal a flattening effect of all surfaces. The electrochemical characterization by cyclic voltammetry shows significant differences depending on the electrode material. The electroactivity of Au is reduced while that of glassy carbon and Pt is greatly enhanced. In particular, the electrochemical behavior of a phosphate LIFT treated Pt showed a marked enrichment of hydrogen adsorbed layer, suggesting an elevated electrocatalytic activity towards glucose oxidation. When Pt electrodes modified in this way were used as an effective glucose sensor, a 1–10 mM linear response and a 10 µM detection limit were obtained. A possible role of phosphate that was securely immobilized on a Pt surface, as evidenced by XPS analysis, enhancing the glucose electrooxidation is discussed.

Sign in / Sign up

Export Citation Format

Share Document