We report a significant increase in the reflectivity of Al(1%wtSi)/Zr multilayers at near normal incidence by using a new concept of multilayer structure. In our design model, the Al layer is divided into a number of layers along the in-plane direction, and the Si layer is inserted between each layer. The advantages of the new multilayer structure could improve the interfacial boundary between Al and Zr layers, lower the interfacial roughness, and disfavor the crystallization of Al in the theoretical fields. To verify those features of the new multilayer structure in the experiment, we have fabricated several different samples, including the traditional multilayers and the new multilayers with and without Si interlayers. Based on the results of grazing incident X-ray reflectometry and extreme ultraviolet measurements, the new multilayers (Al=2.8) with Si interlayers present lower interfacial roughness, and improve the reflectivity to 50.0% at 5° incident angle. Finally, we discuss the benefits of the new multilayers will be widely used not only in the extreme ultraviolet and soft X-ray multilayers, but also in semiconductor industry and other fields. This is also the first report of observations of enhanced reflectivity in the extreme ultraviolet and soft X-ray multilayers by using the new concept of multilayer structure.
