Determination of the density of ultrathin La films in La/B₄C layered structures using X‐ray standing waves

Abstract

Phone: þ31 (0) 30 609 6846, Fax: þ31(0) 30 603 1204Using simultaneous analysis of both the grazing incidence X-ray reflectivity (GIXR) and the angular dependent fluorescence yield from ultrathin layer structures, the densities of thin La and LaN layers of 2-6 nm thickness enclosed by B 4 C layers have been determined with approximately 5% precision. The density of the La layer in these systems is found to be reduced to the bulk La value. This is explained by LaB 6 interlayers formation. The density of LaN layers were similar to the bulk LaN value, which favors this compound as the most energetically stable in LaN/B 4 C layered systems.

Atomic separation in Co/Cu/Co magnetic structures study by hybrid X-ray reflectivity – X-ray standing wave approach

“…3a shows the simulated angular dependence of the distribution of electromagnetic wave intensity in the studied sample. The wave modulations are typical for the X-ray waveguide structures that are typically observed for specially designed samples [20,21] as it increases significantly the in-depth sensitivity of the XSW analysis. This effect was used, for example, for the increase of the analysis sensitivity to the density of ultra-thin films [22] structure of magnetic layers [23].…”

Fabrication and characterization of Sb/B4C multilayer mirrors for soft X-rays

“…La/B 4 C multilayer has the highest theoretical reflectance in the range of 6.7-8.5 nm [6]. However, strong intermixing of the La and B 4 C layers prevents formation of sharp interfaces and causes reduction of the reflectance by a factor of 1.5-2 as compared to the theoretical value [8]. Sb/B 4 C multilayers also have one of the highest theoretical reflectances (Fig.…”