Tunable Source of Monochromatic X-Rays
Creation of the Experimental Model for the Tunable Source of Monochromatic X-radiation and Development of its Applications for Various Forms of X-ray Analysis
Tech Area / Field
- PHY-ANU/Atomic and Nuclear Physics/Physics
8 Project completed
Senior Project Manager
Malakhov Yu I
Belarussian State University, Belarus, Minsk
- RIGAKU Corporation, Japan, Tokyo\nArizona State University / Department of Physics and Astronomy, USA, AZ, Tempe\nBruker Analytik GmbH, Germany, Karlsruhe\nFraunhofer Institute Zerstörungsfreie Prüfverfahren, Germany, Saarbrücken
Project summaryThe objective of the project is the creation of the operating experimental model of a tunable source of quasi-monochromatic X-radiation with smoothly varying frequency and the development of its applications for x-ray analysis, semiconductor and nanostructure technology, medical and biological researches.
The actuality of this problem is caused by the extensive use of X-radiation (XR) for applied investigations connected with the structural analysis of condensed media, non-destructive quality testing in semiconductor technological processes, for diagnostics and selective effect on various objects in medicine and biology (Pietch et al, 1999, see also references in section 13).
The main advantage of XR in comparison with optical radiation is due to a considerably smaller wavelength. This provides a considerably higher resolution of the X-ray devices and stronger local concentration of the radiation energy in the substance.
The need in XR sources, which enable to carry out large amount of work both in x-ray laboratories and in the technological processes of semiconductor production, constantly increases. The growth of sales of x-ray equipment of leading manufacturers, such as "RIGAKU Corp." (Japan), "SIEMENS" (Germany) and others gives evidence to this tendency. The source of XR in such devices is X-ray tubes. They are usually used for generating characteristic XR with fixed frequencies. X-radiation is emitted by nonrelativistic electrons with the energy of about 100 keV. Despite a considerable growth of modern x-ray tubes efficiency, one can’t use the advantages of XR in full measure because the tubes have a considerably lower spectral intensity than optical sources and don’t provide the smooth variation of such important radiation parameter as frequency (K.Yamada, 1999).
Over the last 20 years, the radical progress has been achieved in X-ray scientific investigations and technology, thanks to the applications of the synchrotron radiation (SR) from the ultrarelativistic electrons with energies more than 1 GeV. SR spectrum provides the quasimonochromatic XR with high spectral density and tunable frequency (Handbook, 1983). Such SR beams are produced only in the large accelerators.
The range of problems, which can be solved using intensive XR sources is so wide that large accelerator complexes of the 4-th generation (M.Hart, 1996) are being created now. However, the number of SR channels at already existing accelerators is insufficient and can’t satisfy all the requests for carrying out research and technological tasks. It is necessary to emphasize, that the construction of such an accelerator is a rather expensive project, the realization of which is impossible for many countries. There is only one accelerator in the former USSR in Novosibirsk satisfying modern requirements for SR source.
The realization of the proposed project will make it possible to provide modern industry and scientific laboratories with new XR sources, which on one side could generate XR with the parameters of the same order as SR and on the other side could be compared with X-ray tubes and small-size accelerators in their accessibility and cost.
A number of theoretical and experimental investigations in the framework of the project could lead to the creation of the prototype of small-size tunable source of X-radiation (TSXR) and verify its efficiency in structural analysis, medical and biological researches.
The principles to be used in the model of tunable XR source and methods of its applications have no analogy in the world and this was confirmed by the registration of the corresponding patent in Japan. (Harada et al. 1998).
The participants of the project have great experience in the field of missile technologies and nuclear weapons. They are leading experts in the world in the theory and experimental investigations of XR generation. The first theoretical prediction of a new physical effect of parametric X-ray radiation generated by electrons during their passage through a crystal was made in their papers (Baryshevsky V.G., Feranchuk I.D. et al 1971, 1980, 1983, 1985). The results of the experiments made in CIS, Germany, Japan and other countries (Fiorito et al. 1993г., Asano et al. 1993г., Freudenberger et al. 1995) have confirmed the theoretical interpretation of parametrical radiation properties and possibilities of its application given in these works. This research has also shown the possibility of generating XR with high enough spectral intensity and smooth frequency variation. As it has been recently theoretically justified by the participants of the project (Feranchuk 1999, 2000) this generation mechanism is effective even for electron beams of 100 keV energy used in X-ray tubes. The correctness of the performed theoretical analysis is confirmed by the results of the detailed quantitative description of experimental XR spectra generated by nonrelativistic electrons in a crystal. These results represent a fundamental basis for the achievement of the main goal of the proposed project – to create the laboratory X-ray source with the smooth variation of the radiation frequency for applied research.
The expected results are determined by the fulfillment of the following project tasks:
Task 1. To carry out experimental research of TSXR physical principles of nonrelativistic electron beams. These principles have some advantages in comparison with the known analogs - high spectral density of radiation and smoothly varying frequency in laboratory conditions. The basic TSXR principles have been proposed for the first time in the publications and patents of the project participants.
Task 2. To optimize TSXR and measuring system parameters. The solution of this task will allow to create TSXR prototype for demonstrating its advantages over the known analogs and also for its further use in applied and scientific research.
Task 3. To develop the recommendations for the production of small-size TSXR. The solution of this task will provide optimal configurations of different models of tunable source and detectors, as required by TSXR application.
Task 4. To work out the methods of TSXR application for X-ray analysis. The proposed approach has one advantage in comparison with the known methods of modern crystallography. It makes possible to measure not only the magnitude, but also the phase of structural amplitudes by tuning the radiation frequency into the area of anomalous dispersion of light atoms belonging to complex protein compounds. This procedure can simplify the problem of structure decoding.
Task 5. To develop the methods of TSXR application for surface and defect investigations of crystals and multilayer nanostructures. Such methods enable to carry out express and nondestructive quality control in semiconductor production.
Task 6. To develop the techniques of TSXR application for selective effect on the chosen atoms in medical and biological research. The monochromatism of X-radiation generated by such a source provides a considerable reduction of the radiation dose in comparison with the existing methods.
The greater part of the expected results is based on the original conceptions elaborated by the participants of the project. The rights for intellectual property will be regulated by the procedures, which have been developed by the ISTC.
The realization of the project objectives is of commercial interest for world producers and users of X-ray equipment in various branches of industry, science and medicine. The creation of the TSXR experimental model is supposed to be realized using the basic elements of X-ray technique. This will greatly accelerate the introduction of project results into manufacturing and production methods.
Meeting ISTC goals and objectives is realized in the framework of the project as long as it:
– gives project participants, who are experts in the acceleration and x-ray techniques and have been involved in the development of mass destruction, weapons the opportunities to redirect their talents to perfect industrial technologies for peaceful activities;
– contributes to develop semiconductor production techniques that are traditional for Belarus;
– supports basic and applied research to create effective XR sources. Since such investigations are carried out in leading research laboratories of the world, such collaboration will have a stimulating influence on the integration of the Belarussian scientists into the international scientific community;
– supports the transition to market-based economies.
Scope of activities: the estimated project duration is 36 months, the total project effort being 319 (man/months). The project will be executed in one organization – Belarussian State University. The experimental group will perform Tasks 1 and 2 during 24 months. The result of this stage should be the creation of the experimental model of the X-ray source. At the same time, the theoretical development of TSXR application methods will be carried out according to tasks 4–6. At the final stage (12 months), the experiments and theoretical interpretation of their results will be carried out in conformity with tasks 4–6. During the last 12 months it will be elaborated some recommendations concerning TSXR production (task 3).
Role of foreign collaborators – research laboratory of "RIGAKU Corp." (Tokyo, Japan) and Prof. John Spence (Arizona, USA) are involved in the following types of collaboration:
– participation in the development of work plan;
– exchange of information during project implementation;
– consultations, preparation of joint articles, reports at conferences, patents;
– supply of equipment units and crystal samples;
– verification of the results using independent experiments;
– consultations on Intellectual Property Rights.
The technical approach and the methodology of tasks solving are based on the original theoretical and experimental results obtained earlier by project participants while studying XR generated by ultrarelativistic electrons in crystals. It has been shown for the first time and has been subsequently confirmed by many experimental teams that the high spectral intensity and monochromatism of X-radiation generated by electrons in crystals arises due to the coherent interaction of charged particles with crystal atoms. The project participants have a great experience in working with electron beams, radiation detectors and basic x-ray equipment and facilities. The principles of TSXR applications for x-ray analysis have been described in theoretical works of the project participants. A considerable part of the principles constituting project foundation is protected by invention patent and certificates of authorship.
1. Pietsch U., Holy V., Baumbach T., High-Resolution X-Ray Scattering from Thin Films and Multilayers, Springer, Heidelberg, 1999.
2. Yamada K., Hosokawa T., Takenaka H., Phys.Rev.A, v.59 (1999) 3673.
3. Koch E.E., Handbook of Synchrotron Radiation, North-Holland, Amsterdam, 1983.
4. Hart M., 23-th Course on X-ray and Neutron Dynamical Diffraction (NATO Advanced Study Institute, Erice, 1996), 85.
5. Baryshevski V.G., Feranchuk I.D. Sov. Phys. JETP, v.34 (1971) 944.
6. Baryshevski V.G., Feranchuk I.D. Phys. Lett. A, v.76 (1980) 452.
7. Baryshevski V.G., Feranchuk I.D. J.of Phys.(Paris), v.44 (1983) 913.
8. Feranchuk I.D., Ivashin A.V. J. of Phys.(Paris) v. 46 (1985) 1981.
9. Fiorito R.B., Rule D.W. et al. Phys.Rev.Lett. v. 71 (1993) 704.
10. Asano S., Endo I. et al. Phys.Rev.Lett. v. 71 (1993) 3247.
11. Freudenberger J., Gavrikov V.G. et al. Phys. Rev. Lett. v.74 (1995) 2487.
12. Feranchuk I.D., Ulyanenkov A.P. Acta Cryst. A, v.55 (1999) 466.
13. Feranchuk I.D., Harada J., Spence J., Ulyanenkov A.P. Phys. Rev. E, v. 62 (2000) No.3.
14. Harada J., Hayashi S., Omote K., Baryshevskii V.G., Feranchuk I.D. Ulyanenkov A.P. Method and Apparatus of X-ray Generation, Jap. Pat. Appl. 10-192182 (1998/07/07) Open 12-03680.