Hi Kamel, by noise, did you mean the amorphous hump of the glass substrate?

You can try glancing incidence XRD (GIXRD) at 0.5 deg for getting XRD spectrum of such a thin film. Hope it helps

Hi Kamel, by noise, did you mean the amorphous hump of the glass substrate?

You can try glancing incidence XRD (GIXRD) at 0.5 deg for getting XRD spectrum of such a thin film. Hope it helps

Yes its possible

Dear Kamel

It is normal to obtain noise in XRD pattern, you can use some software like origin or other likes to smooth the line, and hopefully you can get the desired results. But before smoothing you can try the comments by Kiruba M S, this looks more scientific...:)

Information depth of 'normal' XRD is in the range of some µm. So you will 'see' here mainly the glass substrate.

As Kiruba M S mentioned, you should go to GIXRD. In the vicinity of the angle of total reflection you will have penetration depths around 30nm.

For ZnO (density 5,91g/cm³) at Cu K-alpha the critical angle of total reflection is about 0,48°.

So Kiruba M S is right with the angle suggestion.

Good luck

I am agreed with the earliest comments, you can use grazing incidence X-ray diffraction (GIXD) under 0.5 deg for collect diffraction data of surfaces, interfaces, and thin films.

Yes it is possible

I agree with Muhammad Saqib Khan

Even powder also can, ZnO nano structure peak must be broad.

This seems the total diffraction occured from the glass is dominating and it will show broad peak, if you need exact analysis, itis better to inspect using GIXRD at lower angles or TEM diffraction patterning.

Hi Michael Kamel

I got the XRD of ZnO thin film as follows.

I made the thin film of ZnO on microscopic glass coverslips using a spin coating technique. I have used the dispersion of ZnO nanoparticles in ethanol (bought from Sigma Aldrich ). I basically program the spin coater as 500 rpm for the first 15 s and 5000 rpm for the last 45s and then anneal it at 300 oC for 4 min in hotplate.

But Bibek S Dhami ,

what is the expected thickness of your ZnO layer here?

Is it comparable to 50nm?

I guess it may be here about 1 to 2 µm or something like that; but not about 50nm.

But as general information on which peaks should just show up for ZnO your pattern is useful.

Hi Gerhard Martens our film thickness was around 120nm

Ok Bibek S Dhami ,

surprisingly strong signal.

One comment with regard to the original question - it might be nitpicking, however, XRD is usually working at fixed energy, so we do not have a "XRD spectrum". This erroneous term should be avoided, although unfortunately, it can be frequently seen in scientific papers as well.

@ Bibek S Dhami : for a layer of about 100 nm, indeed a very strong signal (i.e. 5x10^5 counts) - what were the experimental conditions?

Best regards, Dirk

I'm also surprised seeing the high intensity of the data. Anyway, for the analysis-part, only the intensity-ratios, FWHM and line-shapes matter.

Another thing to notice is, for such thin film sample, unintentional substrate-contributions come very often, here the hump, which mainly comes at the lower diffraction angles.

So, try to take the data for higher angles as well, at least upto 90 degree. Because ZnO has quite a few moderately intense peaks even at that regime, which will be free of substrate contributions.

If you go for Rietveld refinement, carefully choose background points.

But Souvik Bhattacharjee ,

my impression is, that Michael Kamel does not see any peaks, but only noise.

This can be due a) very low film thickness and b) perhaps due to the absence of (crystalline) ZnO.

Michael Kamel you should share your XRD pattern please..

even the noisy one.

You may gently remove the the thin layer using a sharp needle (do not scratch the glass) under the microscope, then you can do either synchrotron or lab XRD. I did many such measurements of thin films using both lab and synchrotron XRD. GIXRD is the best option to characterize thin films, do not try transmission XRD with glass substrate. Obviously your XRD peaks would be broader due to size effect. You can try a quick Lebail fitting using Fullprof, GSAS or any other equivalent software to see if the Bragg positions of the standard ZnO matching with your XRD pattern.

From the scattering factors, more precisely the structure factors, the three ZnO peaks around 30-35 degree are the most intense, and those at larger Bragg angles are substantially less intense, so I fear they won't be detectable...

Dirk Luetzenkirchen-Hecht

The conditions were: Cu tube at 45kV and 40mA. Divergence slit of 1/8 and anti-scatter slit of 1/16 ( this makes it a semi-parallel beam). The scan range was 10-50 2 theta with a step size of 0.04. Omega was set to 1 degree. 5 sec counting time. Parallel plate collimator 0.27 degree with a proportional counter.

Dear Artur Braun ,

from the titles and abstracts you dealt with XPS, which per se is very surface sensitive.

Do you have also done XRD at these films?

I have not access to the full text(s)...

... sorry from the second paper there are XRD pattern accessable.

So in consequence, if in Michael's sample is ZnO present at all,

the ZnO is either a) amorphous or b) has very small crystallites of only a very few lattice constants.

https://www.hindawi.com/journals/physri/2015/238123/

Thanks Artur Braun

for sharing the xrd pattern.

Very tiny peak, but 'visible' by eye (That's why I asked Michael Kamel above for sharing his pattern).

Amazing; 10nm is about 50 atomic layers (on top of a substrate).

Pushing the limits; congratulations

I think x ray diffraction can be identified on 50 nm thick materials as it makes out more than hundred of atomic layers.

The sufficiency of this thickness to resolve the x-ray pattern is proved by Artur.

So, i would propose to post treat the film after spin off. May be a suitable thermal treatment at relatively high temperature is required.

Best wishes

Now it will be a lot more difficult with Zn than W. I think you will need a parallel primary beam, a göbel mirror. Your specimen must be carefully aligned, and a grazing incident angle at 1 degree or less. Then choose a 2theta tange citering uge intense peaks

Thanks so much for all your helpful comments. I will try my best to follow these comments systematically either through preparation or via measurement and let you know the results once I have any progress.

Best regards to all of you.

HRTEM is good in below 100 nm

Yes, the XRD spectrum is possible for a thin film with a thickness of 50 nm or less. I'll suggest to use low angle XRD for thin films. But in your case, I am curious about the thermal treatment conditions. I think you should optimize your experiment conditions too; If you are not achieving the ZnO crystalline structure. It is quite a difficult task to achieve the crystal structure of ZnO at low temperature annealing.