Study of Soft X-Ray Optical Constants of Thin Films and Development of Soft X-Ray Multilayer Optics

在光学常数测量和初始生长过程的基础研究基础上，发展了各种软X射线多层膜光学元件。该项目的产出可概括如下：1.测量了硅、钼、碳、碳化硅、Rh、Ru等15种软X射线多层膜材料的薄膜样品的光学常数。(M.Yanagihara，J.曹，M.Yamamoto，A.Arai，S.Nakayama，T.Mizuide和T.纳米oka：用于软X射线的超薄Gd膜的光学常数，Rev.Sci。Instrum。60，第2014-2017页(1989))2.还通过测量薄膜样品的总光电子产额得出了光学常数。得到的光学常数与上述(1)的标准反射率-入射角方法测得的结果符合得很好。这证明了所获得数据的可靠性。(Abst.用原位椭圆偏振法研究了超薄膜的初始生长过程，揭示了岛状结构后连续膜的最小厚度。(M.Yamamoto和T.Nanoka：超薄膜光学性质的原位椭偏仪研究，提交给APL.新的软X射线光学，如多层滤光片、多层偏振器已经被开发出来。利用这些光学元件，首次成功地在10 nm波长进行了系统的偏振测量。(H.Kimura、T.Maehara、M.Yamamoto、M.Yanagihara、W.Okamoto、S.Mitani和T.纳米冈：用软X射线多层偏振器测量SR的偏振，将发表在光子工厂活动报告#8(1990)中)

Various Kinds of soft x-ray multilayer optical elements have been developed with bases of fundamental studies of optical constants measurements and of initial growth processes. The outputs of the project can be summarized as follows.1. Optical constants of thin film samples of 15 materials useful for soft x-ray multilayers such as Si, Mo, C, Sic, Rh, Ru were measured. (M. Yanagihara, J. Cao, M. Yamamoto, A. Arai, S. Nakayama, T. Mizuide, and T. Namioka : optical Constants of Superthin Go-ld Films for Soft X-Rays, Rev. Sci. Instrum. 60, pp. 2014-2017(1989))2. Optical constants have also been derived by measuring the total photoelectron yield of thin film samples. The optical constants well coincide to those obtained by the standard reflectance vs. angle of incidence method above (1.). This demonstrates the reliability of the data obtained. (Abst. of annual meeting of Japan Society of Applied Physics, March 1991)3. In-Situ ellipsometry has been applied for the study of initial growth processes of ultra-thin films, which revealed the minimum thicknesses of the continuous film after the island structure. (M. Yamamoto and T. Namioka : In-situ Ellipsometric Study of Optical Properties of Ultrathin Films, submitted to Appl. Opt.)4. New soft x-ray optics such as multilayer filters, multilayer polarizers have been developped. With these optics, first systematic polarization measurements has been successfully carried at a wavelenth of 10nm. (H. Kimura, T. Maehara, M. Yamamoto, M. Yanagihara, W. Okamoto, S. Mitani, and T. Namioka : Polarization of SR measured by soft x-ray multilayer polarizers, to be published in Photon Factory Activity Report #8(1990))