Hey Everyone
I am wondering to know for a deposited film highly oriented let´s say along c-axis in hexagonal structure on sapphire (001), how much will be misleading our interpretation on the growth orientation on using XRD Powder machine (only spinning on sample no other movement) (theta-2theta scan), if one compares it to the same scan in a XRD machine with possibility of different rotations and sample alignment. I am using 2 different XRD powder machines, for one film I do not see the same peaks.
Thank you and regards
According to my experience which I have worked more than two XRD machines, you should use only one machine (any one as your choice) for base material and deposited film material. This will help you for finding your answer.
Thank you Tanwir. More specifically, if you have a film highly oriented along c-axis (50 nm), we expect to observe only 00l peaks. Do you think in Powder XRD we only see those peaks, or we should expect additional peaks in theta-2theta (besides substrate)?
In theta-2theta scan along c-xis you should expect additional peaks. For more information visit
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With powder diffractometer if you see only the peaks corresponding to a given orientation then you can conclude that the sample has a preferential orientation or a unique orientation. If yoy see many peaks and with intensities ratio similar to what tabulated in database for powder diffraction then there is a completely random orientation. A nearly preferentail orientation is also possible as an intermediate case. This is the most common situation with thin films.
Dear Claudio, thank you. So as I got it, if I use thin film XRD, with correct alignment of sample and beam using goniometer, the number of peaks in theta-2theta scan should not show any difference compared to the same scan in powder XRD.
Yes, it is like that, ìf you use the surface as a reference. This may not be true if you have a crystal as a substrate and in that case the lattice planes are a reference rather than the surface, and these may not coincide.
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