Broadband multilayer mirrors for optimum use of soft x-ray source output

A method of designing soft x-ray multilayer mirrors which maximize the throughput of a system in a given wavelength range is described, where throughput is defined as the product of multilayer reflectivity and source spectral intensity. It is shown that the method can also be used to obtain a Aat throughput response in the required wavelength range, and that in either case mirrors which suppress the throughput outside the desired range can be designed. The method is used to optimize multilayers for the wavelength range 13-19 nm, with suppressed throughput in the ranges 12-13 and 19-25 nm. In the latter case the ratio of intensities inside and outside 13-19 nm can be increased from 0.91 to 13 1 and from 0.70 to 35 for two different source spectra and maximized throughput, or to 67 and 25 for flat throughput.