Elemental Profiling of III-V MOSFET High-kDielectric Gate Stacks Using EELS Spectrum Imaging

Spectrum-imaging is a useful technique for comparing different processing methods on very large data sets which are identical for each method. This paper is concerned with comparing methods of electron energy-loss spectroscopy (EELS) quantitative analysis on the Al-Li system. The spectrum-image analyzed here was obtained from an Al-10at%Li foil aged to produce δ' precipitates that can span the foil thickness. Two 1024 channel EELS spectra offset in energy by 1 eV were recorded and stored at each pixel in the 80x80 spectrum-image (25 Mbytes). An energy range of 39-89eV (20 channels/eV) are represented. During processing the spectra are either subtracted to create an artifact corrected difference spectrum, or the energy offset is numerically removed and the spectra are added to create a normal spectrum. The spectrum-images are processed into 2D floating-point images using methods and software described in [1].

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Quantitative parallel EELS spectrum imaging developed as a new tool in AEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013064x ◽

1992 ◽

Vol 50 (2) ◽

pp. 1202-1203

Author(s):

Gianluigi Botton ◽

Gilles L'espérance

Keyword(s):

Statistical Analysis ◽

Spatial Resolution ◽

Personal Computer ◽

Systematic Study ◽

Present Author ◽

Chemical Elements ◽

Detection Limits ◽

Research Groups ◽

Quantitative Performance ◽

Spectrum Imaging

As interest for parallel EELS spectrum imaging grows in laboratories equipped with commercial spectrometers, different approaches were used in recent years by a few research groups in the development of the technique of spectrum imaging as reported in the literature. Either by controlling, with a personal computer both the microsope and the spectrometer or using more powerful workstations interfaced to conventional multichannel analysers with commercially available programs to control the microscope and the spectrometer, spectrum images can now be obtained. Work on the limits of the technique, in terms of the quantitative performance was reported, however, by the present author where a systematic study of artifacts detection limits, statistical errors as a function of desired spatial resolution and range of chemical elements to be studied in a map was carried out The aim of the present paper is to show an application of quantitative parallel EELS spectrum imaging where statistical analysis is performed at each pixel and interpretation is carried out using criteria established from the statistical analysis and variations in composition are analyzed with the help of information retreived from t/γ maps so that artifacts are avoided.

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Energy-filtered imaging of polymer microstructure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163277 ◽

1996 ◽

Vol 54 ◽

pp. 162-163

Author(s):

K. Siangchaew ◽

J. Bentley ◽

M. Libera

Keyword(s):

Energy Loss ◽

Heavy Element ◽

Spectroscopic Imaging ◽

Data Set ◽

Polymer Microstructure ◽

Entire Energy ◽

Staining Methods ◽

Spectrum Imaging ◽

Resolution Data

Energy-filtered electron-spectroscopic TEM imaging provides a new way to study the microstructure of polymers without heavy-element stains. Since spectroscopic imaging exploits the signal generated directly by the electron-specimen interaction, it can produce richer and higher resolution data than possible with most staining methods. There are basically two ways to collect filtered images (fig. 1). Spectrum imaging uses a focused probe that is digitally rastered across a specimen with an entire energy-loss spectrum collected at each x-y pixel to produce a 3-D data set. Alternatively, filtering schemes such as the Zeiss Omega filter and the Gatan Imaging Filter (GIF) acquire individual 2-D images with electrons of a defined range of energy loss (δE) that typically is 5-20 eV.

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Variations in Mineral/heavy metals profiling and preventive role of trichomes in Peach Fruits treated with CaC2

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666200808175723 ◽

2020 ◽

Vol 23 ◽

Author(s):

Muhammad Irfan ◽

Safdar Abbas ◽

Beenish Jehan Azhar ◽

Shakeel Ahmad ◽

Hafsa Muhammad ◽

...

Keyword(s):

Heavy Metals ◽

Nutritional Value ◽

Fine Powder ◽

Calcium Carbide ◽

Control Group ◽

Tandem Accelerator ◽

Health Promoting ◽

Elemental Profiling

Background: Phytonutrients in peach fruits have health promoting antioxidants against various chronic diseases. However, there is no extensive data to show the nutritional values of Local peach cultivars after post-harvest treatments. Objective: Mainly this study was objective to determine the effect of calcium carbide on nutritional value and quality of fruits of Pakistani peach cultivars. Methods: The peach fruits were collected from three different peach orchids of KPK and the fruits were divided into 4 groups while 5th group was collected from local fruit shop. Each experimental group was treated with different concentration of calcium carbide whereas control group was not treated. The peel and pulp samples were oven dried and ground to fine powder separately. The elemental compositions were determined using Particle Induced X-ray emission and Pelletron Tandem Accelerator. Result: Sixteen elements were identified in peach fruits and the elements were Al, P, S, Cl, K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, and Se. In peel, concentration of some elements increased or decreased after treatment with CaC2 while in pulp the conc. of nearly all detected elements was increased in treated samples. We found significantly high amount of heavy metals traces including As, Se, Co, Si, and P in peach fruits treated with CaC2. Interestingly, the presence of trichomes in peach skin prevents the transfer of these heavy metals deep into the pulp which was also verified by the elemental profiling of nectarines. Conclusion: Conclusively, the artificial ripening with CaC2 changed the nutritional value of peach fruits that has higher health risks if consume with the peel. According to our best knowledge, this is the first report that highlights the effects of CaC2 which deteriorate the nutritional value of peach fruits in Pakistan.

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Delineating the Decussating Dentato-rubro-thalamic Tract and Its Connections in Humans Using Diffusion Spectrum Imaging Techniques

The Cerebellum ◽

10.1007/s12311-021-01283-2 ◽

2021 ◽

Author(s):

Si-Qi Ou ◽

Peng-Hu Wei ◽

Xiao-Tong Fan ◽

Yi-He Wang ◽

Fei Meng ◽

...

Keyword(s):

Imaging Techniques ◽

Diffusion Spectrum Imaging ◽

Spectrum Imaging

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Characterization of multiple sclerosis neuroinflammation and neurodegeneration with relaxation and diffusion basis spectrum imaging

Multiple Sclerosis Journal ◽

10.1177/13524585211023345 ◽

2021 ◽

pp. 135245852110233

Author(s):

Irene M Vavasour ◽

Peng Sun ◽

Carina Graf ◽

Jackie T Yik ◽

Shannon H Kolind ◽

...

Keyword(s):

Multiple Sclerosis ◽

Specific Information ◽

Axonal Loss ◽

Normal Appearing White Matter ◽

Relapsing Remitting ◽

Tissue Changes ◽

Spectrum Imaging ◽

Magnetic Resonance Imaging Mri ◽

And Diffusion

Background: Advanced magnetic resonance imaging (MRI) methods can provide more specific information about various microstructural tissue changes in multiple sclerosis (MS) brain. Quantitative measurement of T1 and T2 relaxation, and diffusion basis spectrum imaging (DBSI) yield metrics related to the pathology of neuroinflammation and neurodegeneration that occurs across the spectrum of MS. Objective: To use relaxation and DBSI MRI metrics to describe measures of neuroinflammation, myelin and axons in different MS subtypes. Methods: 103 participants (20 clinically isolated syndrome (CIS), 33 relapsing-remitting MS (RRMS), 30 secondary progressive MS and 20 primary progressive MS) underwent quantitative T1, T2, DBSI and conventional 3T MRI. Whole brain, normal-appearing white matter, lesion and corpus callosum MRI metrics were compared across MS subtypes. Results: A gradation of MRI metric values was seen from CIS to RRMS to progressive MS. RRMS demonstrated large oedema-related differences, while progressive MS had the most extensive abnormalities in myelin and axonal measures. Conclusion: Relaxation and DBSI-derived MRI measures show differences between MS subtypes related to the severity and composition of underlying tissue damage. RRMS showed oedema, demyelination and axonal loss compared with CIS. Progressive MS had even more evidence of increased oedema, demyelination and axonal loss compared with CIS and RRMS.

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