Full Width at Half Maximum (FWHM) Interpretation

[citw]

Very commonly in thin film articles/journals, I find the full width at half maximum of X-ray rocking curves associated with the quality (order) of the surface. For example, if the same material is grown on two different substrates, A and B, with FWHM values of 0.11° for A and 0.6° for B, why do we interpret the quality of the A film to be better than B? In other words, why does a lower FWHM indicate higher crystalline quality?

 

[ZapperZ]

Very commonly in thin film articles/journals, I find the full width at half maximum of X-ray rocking curves associated with the quality (order) of the surface. For example, if the same material is grown on two different substrates, A and B, with FWHM values of 0.11° for A and 0.6° for B, why do we interpret the quality of the A film to be better than B? In other words, why does a lower FWHM indicate higher crystalline quality?

It means the sharper the peak, the less spread in the crystal lattice values. It is more ordered.

Zz.

 

[citw]

Your comment helped me locate a pretty good explanation for different material parameters:

www1.chm.colostate.edu/Files/HRXRD.pdf

Thanks for the help.