Effect of thickness ratio deviation on soft‐x‐ray diffraction of multilayers

The simulation of soft‐x‐ray (λ=1.33–14.0 nm) ‐diffraction behavior at 2θ=90° of W/C and W/Si multilayers with sublayer thickness ratio (composition) deviation in periods is presented. The results show that when the deviation Δx≥0 (which means that the thickness fraction x=d1/d increases from the top to the bottom of the multilayers, where d1 is the thickness of the heavy element sublayer and d the period of the multilayer), (i) in the case of W/Si where the W and Si absorption coefficients are close the diffraction intensities decrease in general, while in the case of W/C where the W and C absorption coefficients are close the increase of the diffraction intensities can reach about 20%; (ii) the full‐width at half‐maximum of the diffraction peak always decreases; (iii) the peak position tends to move to the small‐angle side.