Unravelling secrets from atoms to planets PIXE combined with Kossel diffraction for the analysis of thin film multilayers
Résumé
We present a method combining PIXE and Kossel diffraction to characterize periodic multilayers. These structures are made of an alternation of nanometer thin films and are widely used as dispersive elements designed for the x-ray and extreme UV ranges. Their excitation with protons results in emission of characteristic x-rays by the atoms within the stack. That radiation presents significant interference effects when observed in the vicinity of the Bragg angle corresponding to the x-ray wavelength and multilayer stack period. This is called Kossel diffraction. Thus, when the intensity of this radiation is measured as a function of the detection angle, i.e. in grazing exit condition, around the Bragg angle, a modulation is observed whose amplitude, shape and