A novel interferometric approach where the X-ray amplitude splitting interferometer based on the compound refractive lens was used to visualization of thin layers with a thickness of several nanometers applied to the surface of the membrane. The functional capabilities of the proposed technique were theoretically studied and experimentally demonstrated on the example of the gold strip 8 nm thick deposited on the 1000 nm Si3N4 membrane. The corresponding numerical simulations were performed. It was shown that the interference pattern is very sensitive to small thickness deviations of the gold layer, resulting in the ability to accurately determine not only its average thickness but also to reconstruct its cross-section profile with a nanometer resolution.
We are proposing an X-ray reflecto-interferometry technique using an x-ray microfocus laboratory source for thin-film structure research based on compound refractive lenses. The idea of this technique is to use a very simplified experimental setup where a focused X-ray beam reflected from parallel flat surfaces creates an interference pattern in a wide angular range. Due to this, the interference pattern can be obtained in a single shot without the need to rotate the specimen or the detector. The applicability of this technique has been demonstrated using the MetalJet Excillium microfocus laboratory source, which has GaKα emission line at 9.25 keV. A series of interference patterns for Si3N4 membranes and the experimentally obtained film thickness are in good agreement with the declared characteristics. The main advantages and future possible of the reflecto-interferometry technique are discussed.
A new X-ray Reflecto-Interferometry (XRI) technique is proposed and realized for thin-film characterization. The XRI employs refractive optics that produce a converging fan of radiation, incident onto a sample surface, and a high-resolution CCD detector, which simultaneously collects the reflecto-interferogram over a wide angular range. The functional capabilities of the new method were experimentally tested at the ESRF ID06, and ID10 beamlines in the X-ray energy range from 14 keV to 22 keV. The free-standing Si3N4 membranes with different thickness were studied. The main advantages and possible future applications of the proposed reflecto-interferometry are discussed.
X-ray reflecto-interferometry technique based on compound refractive lenses using an x-ray laboratory source was proposed to study thin-film structures. The setup for this experiment is very simple: a focused x-ray beam is reflected from parallel flat surfaces, which creates an interference pattern in a wide angular range, therefore the interference pattern can be obtained in a single shot without the need to rotate the sample or the detector. The reflecto-interferograms for Si3N4 membranes were obtained using the MetalJet Excillium micro-focus laboratory source with GaKα emission line at 9.25 keV. The experimentally obtained film thickness is in good agreement with the declared characteristics.