Status of small d-spacing X-ray multilayer development at Osmic

摘要

The deposition and X-ray performance of multilayer structures with d-spacings ranging from 1.2 nm to 3.5 nm has been presented. Different pairs of materials such as W (Mo, Ni, Cr, and La)/B_4C, Ni (Cr, Co, V)/C have been considered. X-ray reflectivity of the multilayers has been measured in the photon energy range from ～0.18keV to ～100keV. W/B_4C structures with d～1.25 nm showed reflectivity greater than 30% at Cu-K_α(E～8keV). Performance of a W/B_4C structure with d～1.5nm has been compared with TlAP crystal performance in analysis of Si-K_α (1.74keV), Al-K_α (1.5keV), Mg-K_α(1.25keV) and Na-K_α (1.04keV) radiation. Results showed that small d-spacing multilayers can be considered for TlAP crystal replacement in Wavelength Dispersive X-Ray Fluorescence (WDXRF) spectrometers. The absolute reflectivity of near normal incidence structures at O-K_α (～293eV), C-K_α (～277eV) and B-K_α (～183eV) radiation lines has been measured to be ～1.5%, 14% and 43% respectively with spectral resolution of up to ～0.6%.