Diffraction Peaks in X-Ray Spectroscopy: Friend or Foe?

Abstract

Diffraction peaks can occur as unidentifiable peaks in the energy spectrum of an x-ray spectrometric analysis. Recently, there has been increased interest in oriented thin polycrystalline films and epitaxial films on single crystal substrates for electronic applications. Since these materials diffract x-rays more efficiently than randomly oriented polycrystalline materials, diffraction peaks are being observed more frequently in x-ray fluorescent spectra In addition, micro x-ray spectrometric analysis utilizes a small, intense, collimated x-ray beam that can yield well defined diffraction peaks. In some cases these diffraction peaks can occur at the same position as elemental peaks. These diffraction peaks, although a possible problem in qualitative and quantitative elemental analysis, can give very useful information about the crystallographic structure and orientation of the material being analyzed. The observed diffraction peaks are dependent on the geometry of the x-ray spectrometer, the degree of collimation and the distribution of wavelengths (energies) originating from the x-ray tube and striking the sample.

Combined multiple-excitation FP method for micro-XRF analysis of difficult samples

“…One such factor is features in the spectrum that interfere with weak peaks from trace elements, The features may come from a poorly behaved background, from simply too much background to allow sufficiently low detection limits, from diffraction peaks due to large grains, or from scattered anode lines. Diffraction peaks in particular are common and have been well documented and investigated by several authors (Scruggs et al, 2000, Sutton et al, 1986, Tissot and Goehner, 1992, and Verkhovodov, 2005. In micro-XRF, the particular spot on the specimen may be important.…”

“…The features may come from a poorly behaved background, from simply too much background to allow sufficiently low detection limits, from diffraction peaks due to large grains, or from scattered anode lines. Diffraction peaks in particular are common and have been well documented and investigated by several authors ͑Scruggs et al., 2000, Sutton et al, 1986, Tissot and Goehner, 1992 In micro-XRF, the particular spot on the specimen may be important. Hence, it may not be possible to move to a different location to help reduce the artifacts or make a definitive quantification of an element subject to interference.…”