|Budget Amount *help
¥12,100,000 (Direct Cost : ¥12,100,000)
Fiscal Year 1998 : ¥7,200,000 (Direct Cost : ¥7,200,000)
Fiscal Year 1997 : ¥4,900,000 (Direct Cost : ¥4,900,000)
This project aims 1. establishments of polarization measurements and control in the soft X-ray by improving performances of soft X-ray multilayer polarizing elements to a practical level. In parallel to this, 2. material pairs of the multilayers and their period thicknesses are optimized to increase a wavelength region available. Then, with the high performance polarisers, 3. soft X-ray. ellipsometry will be developed as a new precision method of surface analysis. The two-year research is summarized in the following.
1. Free standing MO/Si multilayers were developed as lambda/4 and lambda/2 plates at a wavelength of l3nm. The polarization performance was evaluated by rotating analyser ellipsometry with use of reflection multilayer polarizer at the photon factory, KEK.
2. Multilayers were developed for the wavelengths of the water window region where the reflectances still remain at a level of a few %. Based on a optical criteria, Sc was paired with Cr, Ni, Si, C, and Al to fabricate multilayers of 100pairs, which revealed Sc/Cr as a pair showing the best periodicity. Further fabrication with improved stability of the sputtering rate and with optimized substrate temperature of around 70oC, Sc/Cr of 250 pairs showed the highest reflectance of 15% at a wavelength of 3.1nm.
3. With polarisers of 0.001 extinction ratio, a sample of 40nm thick Mo layer was studied by soft X-ray ellipsometry. This revealed resonance like structures in the angle of incidence response where extremely high sensitivities of 0.0 1nm for the thickness, 0.001 for the refractive index, and 0.0001 for the extinction ratio were expected by analysis with a single layer model with rough boundaries.