Incorporation of Highly Concentrated Iron Impurities in InP by High Temperature Ion Implantation

2002 ◽  
Vol 719 ◽  
Author(s):  
T. Cesca ◽  
A. Gasparotto ◽  
N. El Habra ◽  
A. Coati ◽  
B. Fraboni ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Annealing Temperature ◽  
Deep Level ◽  
Thermal Treatments ◽  
High Concentration ◽  
X Ray ◽  
Lattice Position ◽  
Defect Reactions ◽  
High Fraction ◽  
Substitutional Fe

AbstractIron was introduced in InP by ion implantation with the aim of obtaining a high concentration of substitutional, electrically active, deep level impurities. A substrate temperature higher than 200 °C was maintained during implantation in order to reduce damage accumulation and Fe defect reactions. The lattice position of the implanted Fe atoms and its modification during annealing treatments was studied by means of Proton Induced X-ray Emission (PIXE) in channeling conditions and correlated with the ion induced damage measured by different techniques. The results show that a high fraction of substitutional Fe atoms is present after the implantation. This fraction is progressively reduced during thermal treatments by increasing the annealing temperature, with the formation of inactive Fe aggregates, probably in the form of small Fe-P complexes.

Double-Crystal X-ray Diffraction Studies of Si ion-Implanted and Pulsed Laser-Annealed GaAs

1990 ◽  
Vol 34 ◽  
pp. 531-541
Author(s):  
P. M. Adams ◽  
J. F. Knudsen ◽  
R. C. Bowman
Keyword(s):  
Ion Implantation ◽  
Laser Annealing ◽  
Pulsed Laser ◽  
Thermal Treatments ◽  
X Ray Diffraction ◽  
Surface Layers ◽  
Double Crystal ◽  
X Ray ◽  
Pulsed Laser Annealing ◽  
Microelectronic Devices

Ion-implantation has many applications in the fabrication and processing of microelectronic devices from semiconductors, but thermal treatments are required to remove defects produced by the implant and to electrically activate dopants. Recently, pulsed laser annealing has been used to activate surface layers of GaAs that have been heavily doped with 28Si+ by ion implantation, and carrier concentrations of > 1 x 1019 cm-3 have been achieved (Ref. 1). Double-crystal x-ray diffraction techniques are very sensitive to strains and defects in single crystals and provide a means for characterizing and quantifying the damage produced by ion-implantation and the subsequent relief of damage by pulsed laser annealing.

Damage Mechanisms of Ion Implanted Bulk (0001) ZnO Single Crystals.

2003 ◽  
Vol 792 ◽  
Author(s):  
B.T. Adekore ◽  
I. Usov ◽  
B. Patnaik ◽  
N. Parikh ◽  
R.F Davis
Keyword(s):  
Ion Implantation ◽  
Single Crystals ◽  
Annealing Temperature ◽  
Amorphous State ◽  
Atomic Mass ◽  
Crystalline Lattice ◽  
X Ray Diffraction ◽  
Damage Mechanisms ◽  
X Ray ◽  
Structural Recovery

ABSTRACTCrystalline damage created by ion-implantation of dopant impurities in ZnO (0001) substrates was characterized as a function of atomic mass of implanted species using triple-axis (2θ-ω/ω) x-ray diffraction and Rutherford backscattering (RBS). The former revealed the presence of implantation-induced strain through the broadening of the isometric and asymmetric 2θ-ω reflections. However, RBS indicated that the damage introduced during implantation of these ions was insufficient to transform the crystalline lattice into a completely amorphous state. Additional XRD characterization as a function of annealing temperature of the implanted materials showed a reduction in the broadening of the isometric reflections, indicating that structural recovery of implanted ZnO crystals can be achieved.

scholarly journals The Effect of PEGDE Concentration and Temperature on Physicochemical and Biological Properties of Chitosan

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1830
Author(s):  
Martha Gabriela Chuc-Gamboa ◽  
Rossana Faride Vargas-Coronado ◽  
José Manuel Cervantes-Uc ◽  
Juan Valerio Cauich-Rodríguez ◽  
Diana María Escobar-García ◽  
...  
Keyword(s):  
Free Amino ◽  
Biological Properties ◽  
Diglycidyl Ether ◽  
Thermal Treatments ◽  
Natural Polymer ◽  
X Ray Diffraction ◽  
Amino Groups ◽  
High Concentration ◽  
Bone Contact ◽  
X Ray

Chitosan (CHT) is a polysaccharide with multiple claimed properties and outstanding biocompatibility, generally attributed to the presence of protonable amino groups rendering a cationic natural polymer. However, the effect of changes in CHT structure due to hydration is not considered in its performance. This study compares the effects on biocompatibility after drying at 25 °C and 150 °C scaffolds of chitosan, polyethylene glycol diglycidyl ether (PEGDE) crosslinked CHT (low, medium and high concentration) and glutaraldehyde (GA) crosslinked CHT. PEGDE crosslinked CHT showed a reduction in free amino groups and the amide I/II ratio, which exhaustive drying reduced further. In X-ray diffraction (DRX) analysis, PEGDE crosslinked CHT showed multiple peaks, whereas the crystallinity percentage was reduced with an increase in PEGDE concentration and thermal treatments at 150 °C. In a direct contact cell assay, high osteoblast viability was achieved at low and medium PEDGE concentrations, which was improved when the crosslinked scaffolds were thermally treated at 150 °C. This was attributed to its partial hydrophilicity, low crystallinity and low surface roughness; this in spite of the small reduction in the amount of free amino groups on the surface induced during drying at 150 °C. Furthermore, PEGDE crosslinked CHT scaffolds showed strong vinculin and integrin 1β expression, which render them suitable for bone contact applications.

Redistribution and precipitation of dopant on thermal annealing of bismuth implanted silicon

1983 ◽  
Vol 41 ◽  
pp. 126-127
Author(s):  
S. J. Pennycook ◽  
J. Narayan ◽  
O. W. Holland
Keyword(s):  
Ion Implantation ◽  
Thermal Annealing ◽  
Cross Section ◽  
Solid Solutions ◽  
Annealing Temperature ◽  
High Dose ◽  
Extended Defects ◽  
High Concentration ◽  
Equilibrium Solubility ◽  
Original Surface

Ion implantation above a certain dose leads to the formation of amorphous layers, which if recrystallized under interface-controlled growth at 450-600°C, result in solid solutions far exceeding the equilibrium solubility limits. In this investigation, we have annealed high-dose implanted specimens at 1000°C for one hour to study the redistribution and precipitation of dopant due to the presence of extended defects.Figure 1 shows a cross section TEM image taken near the [01] Si pole of (100)Si implanted with 209Bi+ (250 KeV, 5 x 1015 cm−2) and annealed (1000°C, 1 hr). As well as a band of precipitates typically 5 nm in size centered at a depth of 100 nm there are some much larger precipitates (28 nm in size) at the original surface of the silicon. These show a curved meniscus protruding out of the surface since the bismuth is liquid at the annealing temperature. These precipitates are located on twins suggesting that the dopant has diffused along the twin boundaries from the band of high concentration to the surface.

X-ray studies of the NaCl:SrCl2 system

1971 ◽  
Vol 27 (4) ◽  
pp. 353-362 ◽  
Author(s):  
E. Laredo ◽  
E. Dartyge
Keyword(s):  
High Temperature ◽  
Point Defects ◽  
Annealing Temperature ◽  
Lattice Parameter ◽  
Thermal Treatments ◽  
X Ray ◽  
X Ray Scattering ◽  
Dilution Enthalpy ◽  
Good Agreement

High-temperature diffraction experiments have been carried out on the NaCl: SrCl2 system, both in its poly- and monocrystalline form. These experiments have led us to the determination of the dilution enthalpy of the SrCl2 precipitates in the NaCl matrix (hD = 0.90 ± 0.05 eV). Brauer's method was used to calculate the distortion around one defect and Eshelby's model was used to evaluate the resulting change in the lattice parameter due to these perturbing centers. The concentrations of defects calculated from these models are in good agreement with those determined chemically. Small-angle X-ray scattering experiments were performed on the same crystals, with suitable thermal treatments, to follow the clustering of defects as a function of the annealing temperature. It is possible to maintain a large amount of nearly dispersed strontium in the lattice by quenching the crystals from high temperature. The point defects agglomerate by successive annealings from 100 to 300°C, forming clusters of increasing sizes. A discussion of the composition of those centers is included.

Cytomembrane Preservation in Tissue Dehydrated Only With Glutaraldehyde and Epon 812 Resin

1973 ◽  
Vol 31 ◽  
pp. 320-321
Author(s):  
Daniel C. Pease
Keyword(s):  
Diffraction Pattern ◽  
X Ray Diffraction ◽  
High Concentration ◽  
Unpublished Study ◽  
X Ray ◽  
Sectioned Material

A previous study demonstrated that tissue could be successfully infiltrated with 50% glutaraldehyde, and then subsequently polymerized with urea to create an embedment which retained cytomembrane lipids in sectioned material. As a result, the 180-190 Å periodicity characteristic of fresh, mammalian myelin was preserved in sections, as was a brilliant birefringence, and the capacity to bind OsO4 vapor in the hydrophobic bilayers. An associated (unpublished) study, carried out in co-operation with Drs. C.K. Akers and D.F. Parsons, demonstrated that the high concentration of glutaraldehyde (and urea) did not significantly alter the X-ray diffraction pattern of aldehyde-fixed, myelin. Thus, by itself, 50% glutaraldehyde has little effect upon cytomembrane systems and can be used with confidence for the first stages of dehydration.

Layered and ion implantation specimens as possible reference materials for the electron-probe microanalysis

1992 ◽  
Vol 50 (2) ◽  
pp. 1652-1653
Author(s):  
G. Remond ◽  
R.H. Packwood ◽  
C. Gilles ◽  
S. Chryssoulis
Keyword(s):  
Ion Implantation ◽  
Reference Materials ◽  
Analytical Techniques ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
X Ray ◽  
Spatially Resolved ◽  
Analytical Expressions ◽  
Original Approach ◽  
Depth Concentration

Merits and limitations of layered and ion implanted specimens as possible reference materials to calibrate spatially resolved analytical techniques are discussed and illustrated for the case of gold analysis in minerals by means of x-ray spectrometry with the EPMA. To overcome the random heterogeneities of minerals, thin film deposition and ion implantation may offer an original approach to the manufacture of controlled concentration/ distribution reference materials for quantification of trace elements with the same matrix as the unknown.In order to evaluate the accuracy of data obtained by EPMA we have compared measured and calculated x-ray intensities for homogeneous and heterogeneous specimens. Au Lα and Au Mα x-ray intensities were recorded at various electron beam energies, and hence at various sampling depths, for gold coated and gold implanted specimens. X-ray intensity calculations are based on the use of analytical expressions for both the depth ionization Φ (ρz) and the depth concentration C (ρz) distributions respectively.

Crystal Transition and Drug-excipient Compatibility of Clarithromycin in Sustained Release Tablets

2020 ◽  
Vol 16 (7) ◽  
pp. 950-959
Author(s):  
Yu Li ◽  
Xiangwen Kong ◽  
Fan Hu
Keyword(s):  
Sustained Release ◽  
Powder Diffraction ◽  
Magnesium Stearate ◽  
Influential Factor ◽  
High Concentration ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Sustained Release Tablets ◽  
Crystal Transition ◽  
Excipient Compatibility

Background: Clarithromycin is widely used for infections of helicobacter pylori. Clarithromycin belongs to polymorphic drug. Crystalline state changes of clarithromycin in sustained release tablets were found. Objective: The aim of this study was to find the influential factor of the crystal transition of clarithromycin in preparation process of sustained-release tablets and to investigate the possible interactions between the clarithromycin and pharmaceutical excipients. Methods and Results: The crystal transition of active pharmaceuticals ingredients from form II to form I in portion in clarithromycin sustained release tablets were confirmed by x-ray powder diffraction. The techniques including differential scanning calorimetry and infrared spectroscopy, x-ray powder diffraction were used for assessing the compatibility between clarithromycin and several excipients as magnesium stearate, lactose, sodium carboxymethyl cellulose, polyvinyl-pyrrolidone K-30 and microcrystalline cellulose. All of these methods showed compatibilities between clarithromycin and the selected excipients. Alcohol prescription simulation was also done, which showed incompatibility between clarithromycin and concentration alcohol. Conclusion: It was confirmed that the reason for the incompatibility of clarithromycin with high concentration of alcohol was crystal transition.

Effect of Annealing temperature on the Structural and Magnetic Properties of TbxY3-xFe5O12(x = 0.0, 1.0, 2.0) Thin Films Prepared by Sol-Gel Process

2012 ◽  
Vol 501 ◽  
pp. 236-241 ◽  
Author(s):  
Ftema W. Aldbea ◽  
Noor Bahyah Ibrahim ◽  
Mustafa Hj. Abdullah ◽  
Ramadan E. Shaiboub
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Vibrating Sample Magnetometer ◽  
X Ray ◽  
Garnet Phase ◽  
Sol Gel Process ◽  
Amorphous Structures

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

scholarly journals A Study of Thin Film Resistors Prepared Using Ni-Cr-Si-Al-Ta High Entropy Alloy

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Ruei-Cheng Lin ◽  
Tai-Kuang Lee ◽  
Der-Ho Wu ◽  
Ying-Chieh Lee
Keyword(s):  
Annealing Temperature ◽  
Phase Evolution ◽  
Amorphous Structure ◽  
High Entropy Alloy ◽  
X Ray Diffraction ◽  
Temperature Coefficient Of Resistance ◽  
X Ray ◽  
High Entropy ◽  
Transmission Electron ◽  
Thin Film Resistors

Ni-Cr-Si-Al-Ta resistive thin films were prepared on glass and Al2O3substrates by DC magnetron cosputtering from targets of Ni0.35-Cr0.25-Si0.2-Al0.2casting alloy and Ta metal. Electrical properties and microstructures of Ni-Cr-Si-Al-Ta films under different sputtering powers and annealing temperatures were investigated. The phase evolution, microstructure, and composition of Ni-Cr-Si-Al-Ta films were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Auger electron spectroscopy (AES). When the annealing temperature was set to 300°C, the Ni-Cr-Si-Al-Ta films with an amorphous structure were observed. When the annealing temperature was at 500°C, the Ni-Cr-Si-Al-Ta films crystallized into Al0.9Ni4.22, Cr2Ta, and Ta5Si3phases. The Ni-Cr-Si-Al-Ta films deposited at 100 W and annealed at 300°C which exhibited the higher resistivity 2215 μΩ-cm with −10 ppm/°C of temperature coefficient of resistance (TCR).

Sign in / Sign up

Export Citation Format

Share Document