Cr/B4C multilayer mirrors: Study of interfaces and X-ray reflectance

Burcklen, Catherine; Soufli, Régina; Dennetière, D.; Polack, F.; Capitanio, Blandine; Gullikson, Eric M.; Meltchakov, Evgueni; Thomasset, Muriel; Adnot, Jérôme; Rossi, Sébastien de; Delmotte, F.

doi:10.1063/1.4944723

Cited by 19 publications

(14 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Other multilayers with thinner B 4 C layers (in the 0.72-1.08 nm range) revealed that the B 4 C layer was fully intermixed with the Cr layer and were thus simulated with a 2-layer model including a pure Cr layer and an interdiffusion layer, indicating that the amount of B 4 C in the multilayer may not be sufficient to form a pure B 4 C layer. 1 [1] and later in this paper. The model used to simulate the multilayer performance was deduced from actual measurements and is also discussed in Ref.…”

Section: Introductionmentioning

confidence: 59%

“…Cr/B 4 C is of particular interest at photon energies in the vicinity of the Cr and B absorption edges, as illustrated in Figure 1, which shows the peak reflectance of optimized Cr/B 4 C multilayers as a function of photon energy around the B K edge and the Cr L and K edges. The reflectance values shown in Figure 1 are based on a model obtained from actual measurements on Cr/B 4 C multilayers 1 and thus correspond to values one could reasonably obtain in practice.…”

Section: Introductionmentioning

confidence: 59%

“…4 5 The BRUKER ® Discover D8 grazing incidence X-ray (GIXR) reflectance measurement apparatus at 8 keV at LCF has been described in Ref. [1].…”

Section: Methodsmentioning

confidence: 99%

“…The model used to simulate the multilayer performance was deduced from actual measurements and is also discussed in Ref. [1].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Lifetime Stability and Microstructure Properties of Cr/B₄C X-ray Reflective Multilayer Coatings

Burcklen

Soufli

Rebellato

et al. 2019

j nanosci nanotechnol

View full text Add to dashboard Cite

This paper demonstrates that highly reflective Cr/B 4 C multilayer interference coatings with nanometric layer thicknesses, designed to operate in the soft X-ray photon energy range, have stable reflective performance for a period of 3 years after deposition. The microstructure and chemical composition of layers and interfaces within Cr/B 4 C multilayers is also examined, with emphasis on the B 4 C-on-Cr interface where a significant diffusion layer is formed and on the oxide in the top B 4 C layer. Multiple characterization techniques (X-ray reflectivity at different photon energies, X-ray photoelectron spectroscopy, transmission electron microscopy, electron diffraction and X-ray diffraction) are employed and the results reveal a consistent picture of the Cr/B 4 C layer structure.

show abstract

Section: Introductionmentioning

confidence: 59%

Section: Introductionmentioning

confidence: 59%

See 2 more Smart Citations

Lifetime Stability and Microstructure Properties of Cr/B₄C X-ray Reflective Multilayer Coatings

Burcklen

Soufli

Rebellato

et al. 2019

j nanosci nanotechnol

View full text Add to dashboard Cite

show abstract

“…Thus the period of the stack is 1.72 nm. Other reflectivity measurements also showed that Cr atoms are present inside the B 4 C layers [26]. The thin B 4 C barrier layers were introduced to prevent the interdiffusion between Cr and Sc layers and can also improve the thermal stability of the stack [27].…”

Section: Methodsmentioning

confidence: 99%

Kossel interferences of proton-induced X-ray emission lines in periodic multilayers

Guen

André

et al. 2016

Nuclear Instruments and Methods in Physics Research Section B:

View full text Add to dashboard Cite

The Kossel interferences generated by characteristic x-ray lines produced inside a periodic multilayer have been observed upon proton irradiation, by submitting a Cr/B 4 C/Sc multilayer stack to 2 MeV protons and observing the intensity of the Sc and Cr K characteristic emissions as a function of the detection angle. When this angle is close to the Bragg angle corresponding to the emission wavelength and period of the multilayer, an oscillation of the measured intensity is detected. The results are in good agreement with a model based on the reciprocity theorem. The combination of the Kossel measurements and their simulation, will be a useful tool to obtain a good description of the multilayer stack and thus to study nanometer-thick layers and their interfaces.  X-ray photons from an x-ray tube [8][9][10] or synchrotron radiation [11][12][13][14]; this case is analogous to the x-ray standing wave technique [14,15] The technique requires a periodic structure to diffract the emitted radiation, thus it has been applied to study crystals and interferential multilayers. However, to the best of our knowledge, Kossel lines have never been observed in multilayers upon particle excitation. It is the aim of this paper to show that it is possible to study multilayers having a nanoscale period upon proton irradiation through the observation of Kossel lines. Experimental detailsThe multilayer used for this experiment was a Cr/B 4 C/Sc periodic multilayer, whose period was repeated 100 times. The samples were deposited by magnetron sputtering onto a silicon substrate. The thickness of the Cr, B 4 C and Sc layers are 0.60, 0.20 and 0.92 nm respectively, as deduced from x-ray reflectivity (XRR) measurements in the hard and soft xray ranges. Thus the period of the stack is 1.72 nm. Other reflectivity measurements also showed that Cr atoms are present inside the B 4 C layers [26]. The thin B 4 C barrier layers were introduced to prevent the interdiffusion between Cr and Sc layers and can also improve the thermal stability of the stack [27]. The multilayer was capped with a 2.5 nm-thick B 4 C layer in order to prevent it from oxidation. Working with this Cr/B 4 C/Sc multilayer enabled us to measure well-resolved Sc and Cr K lines and to detect them at reasonable grazing angles.Indeed, this kind of short-period multilayer is chosen for microscopy or spectroscopy applications in the water window range [28,29] and requires well defined layers. Possible evolution of the multilayer composition was monitored simultaneously via the elastically backscattered protons detected in a passivated implanted planar silicon (PIPS) detector, placed at 165° with respect to the direction of the proton beam. We present in Figure 1 the spectrum so obtained for a total proton dose of 600 µC. Protons scattered from the Cr and Sc atoms appear in the peak near 1800 keV. The area of this peak was monitored, and did not change during the measurements, indicating no measurable loss of matter induced by the beam. As a further precaution, the proton beam ...

show abstract

X-ray Optics and Synchrotron Beamlines

Cramer

2020

Biological and Medical Physics, Biomedical Engineering

View full text Add to dashboard Cite

Cr/B4C multilayer mirrors: Study of interfaces and X-ray reflectance

Cited by 19 publications

References 31 publications

Lifetime Stability and Microstructure Properties of Cr/B₄C X-ray Reflective Multilayer Coatings

Lifetime Stability and Microstructure Properties of Cr/B₄C X-ray Reflective Multilayer Coatings

Kossel interferences of proton-induced X-ray emission lines in periodic multilayers

X-ray Optics and Synchrotron Beamlines

Contact Info

Product

Resources

About

Cr/B4C multilayer mirrors: Study of interfaces and X-ray reflectance

Cited by 19 publications

References 31 publications

Lifetime Stability and Microstructure Properties of Cr/B4C X-ray Reflective Multilayer Coatings

Lifetime Stability and Microstructure Properties of Cr/B4C X-ray Reflective Multilayer Coatings

Kossel interferences of proton-induced X-ray emission lines in periodic multilayers

X-ray Optics and Synchrotron Beamlines

Contact Info

Product

Resources

About

Lifetime Stability and Microstructure Properties of Cr/B₄C X-ray Reflective Multilayer Coatings

Lifetime Stability and Microstructure Properties of Cr/B₄C X-ray Reflective Multilayer Coatings