The development of nanotechnology gives new possibilities for fabrication of different x-ray optical elements. We
present results of focusing properties the compound silicon linear Zone Plate (ZP) for first and second orders. The
compound silicon linear ZP is fabricated by an electron beam lithography and lift-off technology. ZPs structures have
been etched by ion-plasma up to 6μm deep. A linear ZP of the first and second orders fabricated for x-ray radiation
10kev energy, the focal distance is 57sm. The entire aperture is 357.64μm, the width of the outermost zones of the first
and second orders are 595nm, and the number of the first and second order zones are: N(1) + N(2) = 251.The experiment
was performed at the beam line BL29XU Spring-8 of the Japan Synchrotron Radiation Facility. The experimentally and
theoretically investigations were done for x-ray energy at the 10keV and 12.4keV (0.1nm wavelength). The radial
distribution of intensity is determined as a convolution of the zone plate transmission function and the Kirchhoff
propagator in par-axial approximation. The algorithm is based on the FFT procedure and studied by means of computer
programming simulation.
KEYWORDS: Diffraction, Zone plates, Silicon, Electron beam lithography, Hard x-rays, Crystals, Scanning electron microscopy, Laser crystals, Lithography, Nanotechnology
We present the first results of fabrication the circular zone plate by means of high resolution negative tone inorganic
HSQ (Hydrogen Silsesquioxane or XR-1541) electron-beam resist. Fresnel zone plates (FZPs) has been fabricated on the
surface of silicon crystals for the energy from 8keV up to 100keV by electron beam lithography. Three different FZPs
have been fabricated; circular FZP for the first diffraction order, circular compound FZP for the first and third diffraction
order, and linear FZP for the first and second diffraction order. The parameters of the compound FZPs for first and third
order were the following: the focal distance of first and third orders FZP is F =13.229cm for 0.1nm wavelength, the
entire aperture is 400.0016μm, the width of the outermost zones of the first and third orders is 100nm, and the number of
the first and third order zones is 1223.
A new hard X - ray hologram with using crystal Fresnel zone plates (ZP) has been described. An image of Fourier
hologram for hard X- ray is presented. X-ray phase contrast methods for medical diagnostics techniques are presented.
We have developed an X-ray microscope, based on micro focus source which is capable of high resolution phasecontrast
imaging and holograms. We propose a new imaging technique with the x-ray energy 8 keV. The method is
expected to have wide applications in imaging of low absorbing samples such as biological and medical tissue. We used
FIB to reproduction three dimension structures of damaged spinal cord of rat before and after combined treatment with
NT3 and NR2D. PUBLISHER'S NOTE 12/16/09: This SPIE Proceedings paper has been updated with an erratum correcting several issues throughout the paper. The corrected paper was published in place of the earlier version on 9/1/2009. If you purchased the original version of the paper and no longer have access, please contact SPIE Digital Library Customer Service at CustomerService@SPIEDigitalLibrary.org for assistance.
Many physicists limit oneself to an instrumentalist description of quantum phenomena and ignore the problems of
foundation and interpretation of quantum mechanics. This instrumentalist approach results to "specialization barbarism"
and mass delusion concerning the problem, how a quantum computer can be made. The idea of quantum computation
can be described within the limits of quantum formalism. But in order to understand how this idea can be put into
practice one should realize the question: "What could the quantum formalism describe?", in spite of the absence of an
universally recognized answer. Only a realization of this question and the undecided problem of quantum foundations
allows to see in which quantum systems the superposition and EPR correlation could be expected. Because of the
"specialization barbarism" many authors are sure that Bell proved full impossibility of any hidden-variables
interpretation. Therefore it is important to emphasize that in reality Bell has restricted to validity limits of the no-hidden-variables
proof and has shown that two-state quantum system can be described by hidden variables. The later means that
no experimental result obtained on two-state quantum system can prove the existence of superposition and violation of
the realism. One should not assume before unambiguous experimental evidence that any two-state quantum system is
quantum bit. No experimental evidence of superposition of macroscopically distinct quantum states and of a quantum bit
on base of superconductor structure was obtained for the present. Moreover same experimental results can not be
described in the limits of the quantum formalism.
The idea of the quantum computation is based on paradoxical principles of quantum physics superposition and entanglement of quantum states. This idea looks well-founded on the microscopic level in spite of the absence of an universally recognized interpretation of these paradoxical principles since they were corroborated over and over again by reliable experiments on the microscopic level. But the technology can not be able in the near future to work on the microscopic level. Therefore macroscopic quantum phenomenon-superconductivity is very attractive for the realization of the idea of quantum computer. It is shown in the present paper that a chain of superconducting loops can be only possible quantum register. The proposals by some authors to provide the EPR correlation with help of a classical interaction witness the misunderstanding of the entanglement essence. The problem of the possibility of superposition of macroscopically distinct states is considered.
The problem of possible violation of the second law of thermodynamics is discussed. It is noted that the task of the well known challenge to the second law called Maxwell's demon is put in order a chaotic perpetual motion and if any ordered Brownian motion exists then the second law can be broken without this hypothetical intelligent entity. The postulate of absolute randomness of any Brownian motion saved the second law in the beginning of the 20th century when it was realized as perpetual motion. This postulate can be proven in the limits of classical mechanics but is not correct according to quantum mechanics. Moreover some enough known quantum phenomena, such as the persistent current at non-zero resistance, are an experimental evidence of the non-chaotic Brownian motion with non-zero average velocity. An experimental observation of a dc quantum power soruce is interperted as evidence of violation of the second law.
We studied the feasibility to create a Bragg-Fresnel optical element through the use of silicon dioxide films grown on the silicon perfect crystal surface. In our case the Bragg-Fresnel lens structure consists of a set of silicon dioxide rectangular shape etched zones arranged by the Fresnel zone law. The stress within coated and uncoated crystal regions is opposite in sign, whether tensile or compressive. The strain in the substrate crystal lattice directly underneath discontinuities in the deposited film give rise to phase difference between waves diffracted from coated and uncoated crystal regions. This phase difference is known to be dependent on the thickness and composition of film and substrate. In this paper the focusing properties of Si/SiO2 Bragg-Fresnel lenses with 107 zones and 0.3 micrometer outermost zone width were experimentally studied as a function of the silicon oxide thickness in the range of 100 - 400 nanometers. The efficiency of the focusing of hard X-rays was found to be about 16% at energy 10 keV.
Circular and linear zone plates have been fabricated on the surface of silicon crystals for the energy of 8 keV by electron beam lithography and deep ion plasma etching methods. Various variants of compound zone plates with first, second, third diffraction orders have been made. The zone relief height is about 10 mkm, the outermost zone width of the zone plate is 0.4 mkm. The experimental testing of the zone plates has been conducted on SPring-8 and ESRF synchrotron radiation sources. A focused spot size and diffraction efficiency measured by knife-edge scanning are accordingly 0.5 mkm and 39% for the first order circular zone plate.
Silicon planar parabolic refractive lenses with relief depth of 100 micrometer are realized by microfabrication technique. A set of 5 planar lenses with simple parabolic profiles and equal apertures and equal focal distances is realized. This set consists of different number (from 1 to 8) of individual lenses. Lenses with minimized absorption as a set of parabolic segments are fabricated too. Focusing and spectral properties of silicon planar parabolic lenses were studied with synchrotron radiation in the x-ray energy range 8 - 25 keV at the ESRF. Linear focus spots of 1.5 micrometer width were recorded for the parabolic lenses and 1.8 micrometer for the lenses with minimized absorption. The intensity transmission of the lens with minimized absorption is two times greater than this value of simple parabolic lenses at 8 keV and in the x-ray energy range over 15 keV overcomes 90%. Spectral properties of the lenses with minimized absorption are discussed in details. Heatload properties of the silicon planar lenses are analyzed and compared with the lenses made of diamond.
A recently derived radiative transfer equation with three Lorentzian kernels of delay is applied to an albedo problem on a scalar wave field quasi-monochromatic pulse diffuse reflection from a semi-infinite random medium consisting of resonant point-like scatterers. The albedo problem is solved exactly in terms of the Chandrasekhar consisting of resonant point-like scatterers. The albedo problem is solved exactly in terms of the Chandrasekhar H-function, extended analytically into the single scattering complex albedo (lambda) -plane. Simple analytical asymptotics for the non- stationary scattering function is obtained in the limit related to large values of the time variable. The exact analytic solution for the time-evolution of a diffusely reflected short pulse is used to analyze an accuracy of the non-stationary scattering function calculated in the diffusion approximation. It is shown that the diffusion asymptotics describes the exact solution with a relative error not exceeding one percent only at larger values of dimensionless wave propagation time t equals t/to > 200 where to stands for a mean free time of wave radiation between scattering events defined in terms of the wave phase in a random medium consisting of point-like scatterers tuned to the Mie resonance. Besides, the accuracy of the diffusion asymptotics falls off providing that wave scattering approaches the resonance conditions.
Some new physical and technical solutions applied to the development of laser diagnostic complex for the study of local electro-physical and structural characteristics of semiconductor materials and microelectronic devices are presented. The potentialities of introscopy and microtomography in laser scanning microscope when detecting different informative response signals are discussed. Original methods and operation modes for scanning microscopy and tomography of semiconductor crystals are described, in particular, the results of computer and apparatus microtomography using transmitted, scattered, polarized infrared radiation, and optically induced photocurrent.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.