High Resolution XRD Studies of Ion Beam Irradiated InGaAs/InP Multi Quantum Wells

2007 ◽  
Vol 1020 ◽  
Author(s):  
S. Dhamodaran ◽  
N Sathish ◽  
Anand P Pathak ◽  
Andrzej Turos ◽  
Devesh K Avasthi ◽  
...  

AbstractMulti quantum wells of InGaAs/InP grown by metal organic chemical vapor deposition have been irradiated using swift heavy ions. Irradiation has been performed using 150MeV Ag and 200MeV Au ions. Both as-grown and irradiated samples were subjected to rapid thermal annealing at 500 and 7000C for 60s. As-grown, irradiated and annealed samples were subjected to high resolution x-ray diffraction studies. Both symmetric and asymmetric scans were analyzed. The as-grown and Ag ion irradiated samples show sharp and highly ordered satellite peaks whereas, the Au ion irradiated samples show broad and low intense peaks. The higher order satellite peaks of the annealed samples vanished with increase of annealing temperature from 500 to 7000C, indicating mixing induced interfacial disorder. Annealing of irradiated samples show higher mixing and disorder and no higher order satellite peaks were observed. Negligible strain was observed after high temperature annealing of as grown samples. Strain values calculated from the X-ray studies indicate that the irradiated samples have higher strain which has been reduced upon annealing. This indicates that the annealing induced mixing occurs maintaining the lattice parameter close to that of the substrate. The effect of electronic energy loss for interface mixing has been discussed in detail. The role of incident ion fluence in combination with the electronic energy loss will also be discussed in detail. The results have been compared with the literature and discussed in detail.

2012 ◽  
Vol 562-564 ◽  
pp. 11-14 ◽  
Author(s):  
Xin Dong ◽  
Jin Wang ◽  
Hui Wang ◽  
Zhi Feng Shi ◽  
Bao Lin Zhang

NiZnO films were grown on sapphire substrates by metal-organic chemical vapor deposition (MOCVD). Then the films were annealed in vacuum at different temperatures for 1h. The UV emission peak was blue shifted in the photoluminescence (PL) spectra and a dramatic shift of (002) diffraction peak to higher angle was observed in X-ray diffraction (XRD) pattern with the increasing anneal temperature. It showed the band gap and the lattice parameter of NiZnO had been affected by anneal in vacuum. From the X-ray photoelectron spectroscopy (XPS) of the NiZnO film, we can find that the anneal temperature had an important effect on the content of each element in NiZnO quantificationally. In addition, the value of x in NiZnO varied slightly with the anneal temperature increasing. The above phenomena indicated that anneal in vacuum could slightly adjust the percentage of Ni indirectly in NiZnO film and offer a good idea in NiZnO devices facture.


Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3048
Author(s):  
Rok Podlipec ◽  
Esther Punzón-Quijorna ◽  
Luka Pirker ◽  
Mitja Kelemen ◽  
Primož Vavpetič ◽  
...  

The metallic-associated adverse local tissue reactions (ALTR) and events accompanying worn-broken implant materials are still poorly understood on the subcellular and molecular level. Current immunohistochemical techniques lack spatial resolution and chemical sensitivity to investigate causal relations between material and biological response on submicron and even nanoscale. In our study, new insights of titanium alloy debris-tissue interaction were revealed by the implementation of label-free high-resolution correlative microscopy approaches. We have successfully characterized its chemical and biological impact on the periprosthetic tissue obtained at revision surgery of a fractured titanium-alloy modular neck of a patient with hip osteoarthritis. We applied a combination of photon, electron and ion beam micro-spectroscopy techniques, including hybrid optical fluorescence and reflectance micro-spectroscopy, scanning electron microscopy (SEM), Energy-dispersive X-ray Spectroscopy (EDS), helium ion microscopy (HIM) and micro-particle-induced X-ray emission (micro-PIXE). Micron-sized wear debris were found as the main cause of the tissue oxidative stress exhibited through lipopigments accumulation in the nearby lysosome. This may explain the indications of chronic inflammation from prior histologic examination. Furthermore, insights on extensive fretting and corrosion of the debris on nm scale and a quantitative measure of significant Al and V release into the tissue together with hydroxyapatite-like layer formation particularly bound to the regions with the highest Al content were revealed. The functional and structural information obtained at molecular and subcellular level contributes to a better understanding of the macroscopic inflammatory processes observed in the tissue level. The established label-free correlative microscopy approach can efficiently be adopted to study any other clinical cases related to ALTR.


1997 ◽  
Vol 51 (6) ◽  
pp. 880-882 ◽  
Author(s):  
Brian R. Stallard ◽  
Robert K. Rowe ◽  
Arnold J. Howard ◽  
G. Ronald Hadley ◽  
Gregory A. Vawter ◽  
...  

Miniature, low-cost sensors are in demand for a variety of applications in industry, medicine, and environmental sciences. As a first step in developing such a sensor, we have etched a grating into a GaAs rib waveguide to serve as a wavelength-dispersive element. The device was fabricated with the techniques of metal-organic chemical vapor deposition, electron-beam lithography, optical lithography, and reactive ion-beam etching. While full integration is the eventual goal of this work, for the present, a functional spectrometer was constructed with the addition of a discrete source, sample cell, lenses, and detector. The waveguide spectrometer has a spectral resolution of 7.5 nm and a spectral dispersion of 0.11°/ nm. As presently configured, it functions in the spectral range of 1500 to 1600 nm. A demonstration of the analytical capability of the waveguide spectrometer is presented. The problem posed is the determination of diethanol amine in an ethanol solution (about 10 to 100 g/L). This procedure involves the detection of the first overtone of the NH stretch at 1545 nm in a moderately absorbing solvent background. The standard error of prediction for the determination was 5.4 g/L.


2018 ◽  
Vol 934 ◽  
pp. 8-12
Author(s):  
Jian Guo Zhao ◽  
Xiong Zhang ◽  
Jia Qi He ◽  
Shuai Chen ◽  
Zi Li Wu ◽  
...  

A serious of non-polar a-plane AlGaN-based multiple quantum wells (MQWs) were successfully grown on the semi-polar r-plane sapphire substrate with metal organic chemical vapor deposition technology. Intense MQWs-related emission peaks at an emission wavelength covered from 277-294 nm were observed based on the photoluminescence measurement. It was found that the employment of the trimethyl-aluminum (TMAl) flow duty-ratio modulation method which was developed based on the two-way pulsed-flows growth technique played a crucial role to control the Al composition of the non-polar a-plane AlGaN epi-layers. The non-polar a-plane AlGaN-based MQWs were deposited with the new developed TMAl flow duty-ratio modulation technique. Evident-3th order X-ray diffraction (XRD) satellite peak was observed from the high resolution-XRD measurement, proving the successful growth of non-polar a-plane AlGaN-based MQWs with abrupt hetero-interfaces.


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