Determination of Lattice Strain and Crystallite Size in Thin Films [Letter to the Editor]

Warren and Averbach
¹
have described a method for the determination of inhomogeneous lattice strain and crystallite size by means of the Fourier analysis of the x-ray line profile. Their technique requires the measurement of more than the first order of a reflection—in special cases of more than one line. In analyzing this technique, Wagner
²
has stated that it is in fact impossible to separate the influence of strain and crystallite size on the line profile by measuring only one line. However, if the sample is very thin, only one order of reflection and often only one line can be measured. For instance, for a nickel film of about 1000 A thickness and for copper K
α
-radiation, the integrated intensity of the (222) reflection is only about 4 % of that of the (111). This considerable decrease of intensity is due to the Lorentz and polarization factor as well as the atomic scattering and absorption facto