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Questions related from Ravi Ananth
I'm interested in software for simulating instrumental Bragg profile (strain free state), XRR profile and XRD Bragg profile to compare with experimentally obtained diffraction profiles for mono...
01 January 2018 8,705 2 View
I was involved in this RG discussion and came up with this scenario: https://www.researchgate.net/post/Why_wustite_FeO_and_nitride_FeN_have_same_picks_in_GI_XRD?view=5a6ea20e5b4952dd7a765a23 One...
01 January 2018 9,641 33 View
We've looked at an epitaxial film of GaN on a Si substrate using real time 2D Bragg XRD Microscopy (2D XRD rocking curve analysis). This specimen also had intermediate "buffer" layers of AlxGa1-xN...
11 November 2017 2,490 30 View
Real time XRD rocking curve data indicates a very interesting Nano structure in as-grown LiF crystal using the (113)- reflection ACT (asymmetric crystal topography). What Nanostructural features...
01 January 2017 7,790 1 View
Most of the XRD community is presently using 0D point counter or 1D linear PSD (position sensitive detector) in powder diffraction as well as rocking curve analyses. Any mention of the extinct...
12 December 2016 9,177 2 View
This data was acquired using the Onsight Technology AXIS (Advanced XRD Imaging System) 2D real time 27.5um pixel detector (25 mm diameter window) mounted on a Bruker D8 with Cu K Alpha, parabolic...
11 November 2016 6,014 5 View
Nano structural meaning to 3D XRD data: Converting the Bragg condition to crystallographic distortions and lattice strain fields topographically. The objective of any materials characterization...
11 November 2016 1,235 1 View
Relative dislocation density using the approach of Hirsch et al. Dislocation Density, ρ = (β2)/(9.b2) b = Burgers Vector, andβ = Integrated Breadth (computed numerically from XRD profile data) Let...
09 September 2016 2,695 9 View
XRR, X-ray Reflectivity or Reflectometry, is a NDE in situ method used to determine thin film dimensions and surface "flatness" for nearly a century now. What is the typical surface examination...
11 November 2015 10,192 15 View
Conventionally XRR, X-Ray Reflectivity, measurements have been conducted using a point or line source but always using the 0D point/scintillation/proportional type detector without spatial...
08 August 2015 8,478 2 View
X-ray reflectivity (XRR) is a technique abundantly used and vetted, for determining film thicknesses and "flatness" of thin film samples on substrates, over the past century. We have implemented...
07 July 2015 5,956 10 View
We are using a Bruker D8 diffractometer for XRD rocking curve analyses. We are interested in finding out the procedure for sending out Metadata parameters to an external device through any of the...
03 March 2015 6,717 3 View
We have super high resolution (76um Pixel,
11 November 2014 831 16 View
i. How does one adjust for this type of sample displacement error (see figure in link below) with a conventional diffractometer measurement using the ubiquitous 0D Geiger counter (point...
11 November 2014 5,893 14 View
XRR, XRD Rocking Curve - (ω-2ϴ/ω/φ/χ)Omega-2Theta Scan, Omega Scan, Phi Scan & Chi Scan! NIST2000SRM - An important HRXRD (High Resolution XRD) Calibration Standard for symmetric and...
11 November 2014 8,517 37 View
We have acquired transmission Laue images from a Lysozyme crystal using a rotating anode at 5kW power. Point focus beam size about 200um or less. We have implemented some time tested image...
10 October 2014 7,898 3 View
"My question is, if we use Rietveld refinement to get particle size, is the size measured a volume weighted size distribution or weighted by a different factor? Whatever the answer is, please...
10 October 2014 9,892 6 View
0D or the conventional Geiger counter type detectors have been in use since the Braggs. How does this match up against the more modern 1D & 2D detectors? Let us say I'm using a high resolution...
07 July 2014 5,092 13 View
Would the accepted methods for determining particle size of Nano powders include the following? 1. TEM 2. SEM 3. STEM 4. XRD 5. Laser Scattering 6. Other
06 June 2014 6,322 44 View
The X-ray Rocking Curve method has been perfected over the past half century to include the ability of examining homo-epitaxial and hetero-epitaxial structures. My interest would be in the...
02 February 2014 3,382 9 View
Bragg XRD Microscopy, a NDE tool that has been tried and tested for over a century was limited in spatial & temporal resolution by the detecting device. Presently the state-of-the-art in real time...
02 February 2014 3,416 12 View
Quantifying the "preferred orientation" in an Aluminum foil (0.2mm) sample using 2D diffractograms obtained with transmission Laue geometry: Figure 1. 2D & 1D diffractograms compared, Al...
01 January 2014 8,309 10 View
In order to use XRD to measure the epi film thickness precisely, several conditions must be met including and not limited to: 1. The sample must be assumed optically flat which is invariably the...
12 December 2013 4,599 10 View
Bragg profile is also known as RCP-Rocking Curve Profile or RSP-Reciprocal Space Profile. Let us examine this difference between the substrate (usually CZ grown) and an epitaxial structure grown...
12 December 2013 9,675 11 View
1. Sensitivity of the XRD data on precise alignment. 2. Unwillingness to verify alignment prior to each measurement. Time prohibitive! 3. Unavailability of a real time tool to precisely "re-align"...
11 November 2013 4,878 31 View
"The intellect has little to do on the road to discovery. There comes a leap in consciousness, call it intuition or what you will, the solution comes to you and you don't know how or why." Albert...
10 October 2013 1,787 3 View
Are there any publications concerning these topics? 1. Sub-grain/Mosaic Structure 2. Stacking Faults 3. Twinning 4. Dislocations 5. Other YouTube GaAs (004) Symmetric reflection (& more examples...
10 October 2013 5,053 10 View
Real Time Bragg XRD Microscopy with GaAs symmetric (004) Bragg reflection: http://www.flickr.com/photos/85210325@N04/9430820747/ Is the asymmetry due to: 1. Theory 2. Stacking Faults 3. Twins 4....
08 August 2013 583 32 View
I'm just reading this Caltech article and trying to decypher it. I surely could use some help understanding how to use peak position and intensity of the SL harmonic reflections to determine SL...
04 April 2013 638 29 View
Conventional XRD Pattern with a 0D point/scintillation detector/counter. We've used the diffraction pattern from the flat Aluminum holder as reference standard and shifted all the diffractograms...
03 March 2013 6,278 38 View
Image magnification with XRD using oblique angle of incidence on the detector: A unique method is proposed, with experimental evidence to substantiate, for magnifying topographic images using XRD....
01 January 1970 7,418 5 View
I'm perplexed by the appearance of "striations" on this (113)- asymmetric reflection XRD topograph for the NIST 2000 sample. Both front and back! The topographs have been created by integrating...
01 January 1970 7,395 3 View
What is the physical meaning of lattice micro strain and mean square micro strain? What is the difference between micro strain and mean square micro strain? A matter of scale or semantics?
01 January 1970 6,526 0 View