EXPERIMENTAL PERFORMANCES OF IMPLANTED LAMELLAR X-RAY MULTILAYER GRATING - COMPARISON WITH CONVENTIONAL ETCHED MULTILAYER GRATING

An original way is given to perform X-ray diffractive optics based on local intermixing with energetic ions. The valleys of the conventional X-ray multilayer grating are replaced by mixed multilayer parts with low reflectivity. This new structure obtained by ion implantation inst ead of etching is called implanted multilayer grating. In this paper w e report on diffraction measurements of implanted and etched multilaye r grating at the Cu K-alpha emission line. Comparative investigations demonstrate first the capability to perform diffractive optics with a new process and second, show similar diffraction efficiencies for both multilayer gratings. The implanted grating, which keeps a bulk struct ure after irradiation has therefore a better resistance to mechanical stresses. Additionally it allows us to perform new optics, using a sup erposition of several plane diffractive structures. (C) 1998 Elsevier Science B.V. All rights reserved.