Actually, I want to find the relationship between XRD peak intensity with conductivity and transmission of any TCO (Transparent Conducting Oxide) material.
Films with higher thickness and good crystalline nature shows intense peak. But with increasing thickness the trasmittance reduces. Conductivity of film depends on its crystalline nature.
In addition to Chandra Bhal's reply, from experience the conductance also improves with increasing TCO thickness (if you measure with 4 point probe). And so maybe you get a more reliable estimate of your conductivity.
Hi Laxmikanta,
There are several possible answers to this question- the effect of crystalline vs. amorphous depositions and thickness of deposition have been covered by the first two answers. (Although I should mention that there is a lot of research being conducted on amorphous TCO materials, as these can have some very interesting properties)
A second factor to consider would be preferential orientation observed in XRD patterns- all thin film materials display preferential orientation, as when a thin film is grown on any substrate it is strained by the substrate underneath and so does not grow in all directions to the same extent as it would do when grown as a single crystal.
It is often found that certain diffraction planes for a TCO are associated with improved electrical conduction- for instance in fluorine-doped SnO2, the fluorine incorporation induces a change in the preferential orientation towards the [211], and a dramatic improvement in the electrical properties vs. undoped SnO2 is seen.
This will be material dependent, so I suggest you find a particular TCO material you are interested in and see if you can find literature that shows that a particular preferential orientation is associated with improved TCO properties.
As for the optical transmission of the films, XRD alone will not give you very much information- you will really require UV/vis spectroscopy to give you this data, as the optical transmission will be influenced by the band-gap of the material (band-gap greater than 3.0 eV is required for visible light transmission), the mass absorption of the material (essentially how thick it is, greater than 1 micron and films start to appear cloudy) and the number of free electrons/holes moving in the material (if you get to x10^23 as the charge carrier concentration, the material will appear opaque even if it has a large band-gap, as the free electrons will start to interact with the visible light photons).
I hope that helps!
Michael
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