Hard X-ray focusing resolution and efficiency test with a thickness correction multilayer Laue lens

The multilayer Laue lens (MLL) is a diffractive focusing optical element which can focus hard X-rays down to the nanometer scale. In this study, a WSi2/Si multilayer structure consisting of 1736 layers, with a 7.2-nm-thick outermost layer and a total thickness of 17 mu m, is prepared by DC magnetron sputtering. Regarding the thin film growth rate calibration, we correct the long-term growth rate drift from 2 to 0.6%, as measured by the grazing incidence X-ray reflectivity (GIXRR). A one-dimensional line focusing resolution of 64 nm was achieved, while the diffraction efficiency was 38% of the - 1 order of the MLL Shanghai Synchrotron Radiation Facility (SSRF) with the BL15U beamline.

Automated summary

In this study, a multilayer structure consisting of WSi2/Si thin films was successfully prepared for the fabrication of a multilayer Laue lens (MLL) capable of focusing hard X-rays to the nanometer scale. The growth rate of the thin films was calibrated to improve the performance of the optical element.