Kossel diffraction observed with X-ray color camera during PIXE of nano-scale periodic multilayer

Abstract

By combining Kossel diffraction with particle induced X-ray emission, we have developed a new methodology to analyze nano-scale thin films. We report the Kossel diffraction generated by irradiating Pd/Y based nano-scale periodic multilayers with 2 MeV protons. The intensity of characteristic Pd Lα X-ray emission is measured as a function of the detection angle (grazing exit). An oscillation of its intensity is observed when the detection angle varies around the Bragg angle, which corresponds to the energy of the emission and the period of the multilayer. Use of the X-ray color camera enables the whole setup to be fixed so that no angular scan is required, greatly simplifying the experimental condition. From the features of the Kossel curves, we are able to deduce that nitrided Pd/Y multilayers exhibit much less layer intermixing than the non-nitrided multilayers. The experimental results show that it is possible to distinguish by the shape of Kossel curves of multilayers with B4C barrier layers located in different interfaces. This demonstrates that Kossel diffraction is structural sensitive.