Broadband multilayer polarizers for the extreme ultraviolet

Abstract

Nonperiodic molybdenum/silicon broadband multilayer polarizers have been designed using numerical optimization algorithm and fabricated using direct current magnetron sputtering. Their performances have been characterized using the high precision eight-axis soft x-ray polarimeter at the BESSY facility. Different multilayers have measured s-polarized reflectivities of 27% at 13.1nm and higher than 15% over the wavelength range of 13–19nm. Nearly constant s reflectivity, up to 37%, is observed over the 15–17nm wavelength range, where the degree of polarization is more than 98%. Furthermore, these multilayer polarizers also show high s reflectivity and polarization over a broad angular range at fixed wavelength.

SiC/Mg multilayer reflective mirror for He-II radiation at 30.4 nm and its thermal stability

“…After design and optimization, the SiC/Mg multilayers were prepared by an ultra-high vacuum direct current magnetron sputtering deposition system (JGP560C6, made in China), which was described in previous article/s [10][11][12][13][14][15][17][18][19]. This system typically reaches a base pressure of about 5 6 10 25 Pa.…”

“…In this article, some multilayer reflective mirrors were studied for He-II radiation (30.4 nm). Usually, at wavelengths longer than the Si L-absorption edge near 12.4 nm, the multilayer material combinations based on Si are widely used in the 13 -20 nm region [10][11][12][13][14][15]. The Mo/Si multilayer was widely used for its high stability and fairly high reflectivity, especially under the motivation of an EUV lithograph in the integrated circuit industry.…”

Design and Characterization of EUV and X-ray Multilayers

“…The second is based on Kozhevnikov's study [17], which is an analytic method that gives an approximate initial depth-graded structure to enable a faster approach to the optimum solution. This method has been applied to various broad-angle [57] and broadband [58] designs of multilayer mirrors. The expression for the reflectivity of a depth-graded multilayer mirror is ( )…”

Broadband Mo∕Si multilayer transmission phase retarders for the extreme ultraviolet

“…8 However, traditional periodic multilayers have narrow bandwidths, which greatly limit their use in practice. The use of aperiodic multilayer structures can overcome these limitations; 9 such broadband reflection analyzers [10][11][12] have been developed, and the same method is used here to develop Mo/ Si broadband transmission phase retarders. The aperiodic Mo/ Si multilayers were made on silicon nitride membranes using direct current magnetron sputtering.…”