| Summary: | This thesis reports on the study of x-ray mirrors that operate at normal incidence
for 45 Å wavelength used in applications such as x-ray microscopy, x-ray astronomy, x
ray lithography, x-ray imaging, and x-ray lasers. These mirrors are fabricated by
alternately depositing two materials of different scattering factors to form a multilayer
structure. A theoretical treatment to identify new combinations of materials for these
mirrors was provided. Carbon and inconel were then selected for ‘low index’ and ‘high
index’ layers, respectively, in the multilayer system.
The thin film laboratory at U.B.C. was set-up for x-ray multilayer research by
automating a sputter coater to allow for the deposition of multilayers and by developing
the appropriate software for data analysis. The optical and structural properties, the
chemical composition, and the thermal stability of the deposited materials were measured
as a function of argon pressure and substrate bias voltage using X-ray Photoelectron
Spectroscopy (XPS), X-ray Diffraction (XRD), Grazing X-ray Reflectometry (GXR), and
Spectroscopic Ellipsometry (SE). Multilayers grown at a low pressure and a moderate
substrate bias (—40 to —80 V) were found to be the most suitable for x-ray reflectors.
Also, samples for second order reflection (period = 45 Å) were found to be more stable
than samples for first order reflection (period = 22.5 Å).
In situ ellipsometry was used to monitor the deposition of single layers and
multilayers of inconel and carbon. Valuable information was obtained regarding the early
stages of film growth, interdiffusion at the interfaces, porosity of the films, etc. The
coalescence thickness of inconel was found to be 10 Å . Interdiffusion was found to occur
at the ‘carbon-on-inconel’ interlace because of the rough underlying inconel layer but not
at the ‘inconel-on-carbon’ interface because of the smooth underlying carbon layer.
Interdifusion at the ‘carbon-on-inconel’ layer was also found to increase with the number
of layers. The control routine worked well. However, timing was found to better control
the reproducibility of the thickness. === Science, Faculty of === Physics and Astronomy, Department of === Graduate
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