Oxide Nanoparticles in Lead Melt
Development of Technology for Production of Nanodimensional Oxide Materials in Lead Melt for New Microsystem Method of Forming Sensitive Layers of Semiconductor Gas Sensors
Tech Area / Field
- MAN-MAT/Engineering Materials/Manufacturing Technology
8 Project completed
Senior Project Manager
Mitina L M
FEI (IPPE), Russia, Kaluga reg., Obninsk
- Karpov Institute of Physical Chemistry, Russia, Moscow
- Nova Trade Consulting Oy, Finland, Vantaa\nOhio State University, USA, OH, Columbus\nForschungszentrum Karlsruhe Technik und Umwelt, Germany, Karlsruhe\nForschungszentrum Karlsruhe Technik und Umwelt / Insritute for Nuclear and Energy Technology, Germany, Karlsruhe\nEnvironmental Systems Corporation, USA, TN, Knoxville
Project summaryThe objectives of this Project are:
– the development of technology for production of nanodimentional semiconductor oxide materials in lead melt;
– the development of theoretical and experimental fundamentals for new base-line microsystem method of forming thin (to 500 A°) sensitive layers of semiconductor ozone sensors by sedimentation of nanodimentional oxide particles onto chips–substrates from aqueous polymer solutions.
Within the frame of Project, the following tasks are to be solved:
1. Theoretical and computational substantiation of possibility of synthesis of nanodispersed semiconductor metal oxides featuring gas-sensitive properties in lead melt, when liquid metal Pb-Me systems are treated by mixtures H2Ar.
2. Construction of new large volume laboratory apparatus for nanodispersed oxide synthesis in lead melt (at a production capacity of 5 g of an oxide per 24 hours).
3. Study of the dissolution kinetics of selected metals in lead and the processes of selective oxidation of binary liquid systems Pb-Me using the newly constructed laboratory apparatus. Production of indium oxide samples and samples of oxides of other selected metals.
4. Study of the properties of nanodimensional materials synthesized in lead melt.
5. Construction of test apparatus and running of investigations on putting thin films of nanodimensional semiconductor oxides generated by means of new technology on sensor chips-substrates under conditions approached to microelectronics production conditions.
6. Construction of test facility for check-up tests of thin nanodimensional oxide films put by new method onto integral chips-substrates of gas sensors (by sedimentation from aqueous polymer solutions). Carry-out of the full set of check-up tests and physical-chemical, mechanical and other examinations of thin nanodispersed oxide films of different composition, produced by new procedure.
7. Creation of pilot microsystem semiconductor gas sensors for low concentration of ozone in air.
8. Implementation of measures oriented to fulfillment of Project objectives and tasks.
Presently, in many countries round the world researchers carry out studies in the field of the development of ultradispersed (nanodimensional) oxide and other materials. It is common knowledge, that it is the fine structure that allows such materials to feature more pronounced properties of semiconductive, heat- and electroinsulation, sorptional, catalytic and other nature. Among the well-known methods of production of ultradispersed oxides, the sol-gel method can be singled out, which consists in building up in aqueous (alchohol) solutions of colloid systems and in their subsequent drying from solvent under supercritical conditions in autoclaves. Aerogel of silicon oxide and more rarely of oxides of other materials, that refer to nanostructurized materials are produced in 9 research centers being in U.S.A., France, Germany and Sweden for research purposes and in two companies «Aeroglass», Sweden and «Thermalux», USA for commercial purposes by the Kistler method (based on sol-gel procedure). Commercial use of aerogel SiO2 is primarily associated with the production of thermoinsulation materials for wall and window coatings. The effect of light absorption by silicon oxide aerogel in ј-wave range of wavelengths enabled the substantiation of the possibility of using such nanodimensional material for Cherenkov counters. Another well-known method of ultradispersed oxide production proposed by Yu.V. Kotov, the corresponding member of the Russian Academy of Sciences, is the electric arc burst evaporation of metallic wire in oxidative medium. The oxides of copper and iron, being produced in such way found their application in catalytic reactions. Other methods of nanooxides production (mechanical crushing of large dispersed oxide particles, plasmatic and detonational modes of synthesis) also are known. The abovecited known methods of ultra-dispersed material generation have quite definite shortcomings associated with large energy consumption (to provide high temperatures, pressures, applied electric-arc voltages, etc.) or with expenses related to the ecological safety when using aggressive reactants or with expenses on additional purification of produced materials (this is primarily true for substances being synthesized by electric-arc burst of metallic wires, by detonation or plasma method) or with a low effectiveness of the process (at mechanical crushing of large size oxides, one manages to obtain no more than 10% of the mass of nanodimensional particles, which then can be hardly separated).
The method of nanodimensional aerogel particles production based on aluminium oxide at selective oxidation of binary melt Ga-Al by gas mixture H2O-Ar, proposed in SSC RF IPPE in 1997, was successfully approved and further developed during the course of Project №733 supported by the ISTC in 1998 (Physico-Chemical Bases of Aluminium Oxide Aerogels Synthesis and Development of Continuous Technology for Their Production from Ga-Al Liquid Metal System). The final report on this Project is attached.
From the viewpoint of the development of technology for nanodimensional semiconductor oxide materials, the present Contract is the continuation of ISTC Project №733. As a result of implementation of the abovementioned Project, the methodology has been established for the development of technology of nanodimensional oxide synthesis in any non-alkaline liquid metal medium. Undoubtedly, there exist also more serious differences in the physical-chemical properties of gallium and lead. Different solubility of metals in liquid gallium and lead, their different viscosity, difference in the ranges of liquid state temperatures, a great series of electronegative (having large affinity to oxygen) metal-microcomponents for lead - all this is an incomplete list of differences between the two liquid metal media. It is the narrowness of the series of electronegative metals – microcomponents in gallium, that makes it impossible to produce oxides of indium, zinc, tin and others, which, theoretically, are formed in lead.
There are good reasons to believe that the first objective of the present Project – the development of technology for production of nanodimensional semiconductor oxides from lead melt – will be successfully implemented, since beside the experience of ISTC Project №733 implementation and positive results of production of ultradispersed indium oxide in lead using the existing laboratory setup, a rather great experience has been accumulated at the SSC RF IPPE for more than 30 years in liquid metal test facility designing and operation. The qualification of SSC RF IPPE’s professionals involved in project is sufficiently high: 1 doctor of techn. science and 10 candidates of technical and physical-mathematical sciences. Among the engineering and technical personnel, many professionals are of high qualification. They have patents, publications and reports on topics related to the liquid metal purification and the synthesis of new materials in melts of gallium and lead.
As mentioned above, the second objective of the present Project is the development of theoretical and experimental fundamentals of new base-line microsystem method for building up thin (to 500 A°) sensitive layers of semiconductor ozone sensors by sedimentation of nanodimensional oxide particles on chips–substrates (Al2O3) from aqueous solutions of polymers.
The microsystem technologies are considered to-day to be the key technologies, the economical potential of which is comparable with that of the microelectronics. According to the results of market studies, these technologies are very extensively developed in the U.S.A., Japan, and Germany. In the U.S.A., where microelectronics is highly developed, the production of complete components is very extensively developed based on microsystems; in Germany, the applied directions have received significant growth, and the microsystem technologies are integrated into production processes, to make final product cheaper and up-grade its consumer’s characteristics. In Japan, the miniaturization always was an important trend in production development, therefore, to-day, each Japan company actually involves a research department dealing with the problems of microsystem technologies in the free search mode. In Russia, the microsystem technologies are practically not developed, though rather extensive researches are under way in this direction.
Among the microsystem technologies, the microsensor semiconductor gas transducers (for instance, for portable gas analyzers, process procedure control systems and so on) occupy a special place by two reasons. First, principally, they are the simplest and cheapest devices for detecting gases and vapors of liquid and solid phase materials in air and those dissolved in water. However, it turned out, that these microsystem devices are most sophisticated from the viewpoint of quantity production. As far as the performance characteristics of semiconductor sensor are strongly dependent on the structure, the composition and the pattern of the thin oxide film of the sensitive layer (500 A°) built up on chips-substrates, each sensor component produced by one of the known methods of sensitive layer putting-on (for example, by stencil stamping, laser impulse, magnetron sputtering, centrifugation, etc.) has its own characteristics and represents an inpidual device. Thus the solution of the general problem of commercial production of microsensor gas sensors and microsystems on their basis is primarily associated with the development of commercial technology of sensitive layers putting-on compatible with the microelectronics production cycles.
It follows from above, that if the fundamentals of the new base-line microsystem technology for putting sensitive layers on chips-substrates will be created in the frame of the present Project, then this will be great success achieved in solving the problem of quantity production of microsensor semiconductor ozone devices.
There are good reasons to believe that the abovementioned objectives of Project will be successfully achieved, because a great experience has been gained at SSC RF –Karpov Research Physical-Chemical Institute (SSC RF NIFHI), where since the 50-s the study of sensor properties of semiconductor metal oxide films is under way. A vast scientific potential has been accumulated for this time, and more than 500 scientific papers are published. At the SSC RF NIFHI, a pilot laboratory device («Sensor ozone analyzer» that was awarded with «Large Gold Metal» at exhibition «Eureka-95», Brussels, 1995) has been developed. The staff involved in Project implementation consists of 1 doctor and 9 candidates of chemical and physico-mathematical sciences as well as of high qualification engineers and technicians. This staff has a number of RF patents,author certificates and know-how on the composition of sensor transducer sensitive layer materials as well as on the procedures of their putting-on and preparing to operation. The staff has at its disposal research equipment for preparation, study and check-up tests of thin oxide films-sensitive layers of ozone sensor devices.
The expected results of the proposed Project are:
– comprehensive scientific-technical substantiation of the technology for production of nanodimensial semiconductor oxide materials in lead melt;
– construction of test apparatus at SSC RF IPPE site, having a production capacity of no less than 5g per 24 hours by any semiconductor oxide synthesized according to the liquid metal technology under development (this apparatus will be the prototype for manufacturing the pilot apparatus in future);
– pilot batches of nanodimensional semiconductor oxides In2O3, SnO2 and others (each no less than 100 g);
– procedures for generation of highly diluted suspensions from separate (nonagglomerated) nanodimensial oxide particles of one or several compositions in aqueous solutions of water soluble polymer series;
– construction of two test apparatuses at SSC RF NIFHI (to put on chips-substrates of thin films of nanodimensial oxides from the aqueous solutions of polymers and to run check-up tests of produced films;
– chips-substrates with gas sensitive homogeneous films of nanodimensional oxide particles of given composition and thickness, which feature optimal operating gas sensitive characteristics, mechanical strength and adhesion (pilot specimens of MS sensors for ozone);
– recommendations on further application of Project results;
– publications and reports on the results of conducted studies.
The applied importance of the proposed Project is that it will be the initial stage of Project on the base-line microsystem technology for putting-on of sensitive layers of semiconductor ozone sensors.
The scope of work to be done in the frame of the present Project covers:
– detailed analysis of factors influencing the formation of semiconductor nanodimensional oxide materials in lead melt (solubility of metal components in lead at 400-1000°C, thermodynamics of their selective oxidation by steam in lead melt);
– analysis of available results on aerogel production based on Al2O3 from Ga-Al melt and synthesis of nanodimensional semiconductor oxides in liquid lead;
– construction of large volume apparatus (design, manufacture, mounting and start-up) of a production capacity of no less than 5 g per day (24 hours) by any nanodimensional semiconductor oxide being synthesized inpidually;
– R&D of technology for synthesis of required materials using the constructed apparatus and production of pilot batches of these materials (100 g each);
– study of microstructure, phase composition and gas sensitive properties of produced oxide materials;
– creation of data base on properties of oxide materials produced under different synthesis conditions (lead temperature, humidity and flow rate of oxide gas mixture, content of dissolved oxidable metallic component in lead, etc.);
– construction of test setup for running tests on putting thin films of nanodimensional semiconductor oxide materials on chips-substrates;
– development of procedures for production of highly diluted suspensions from separate (nonagglomerated) nanodimensional oxide particles of one or several compositions in water solutions of polymer series;
– investigation of the synthesis of homogeneous films of given composition and thickness at controllable sedimentation of nanodimensional particles on chips-substrates;
– tests of treatment techniques of produced film (magnetic field, thermal and others) with the aim of reaching its optimum operating gas sensitive performances, mechanical strength and good adhesion;
– construction of test facility for running check-up tests of produced thin films;
– full set of checking, physical-chemical and mechanical tests of films of different compositions, produced by the new technique of chip-substrate covering;
– production of pilot microsystem semiconductor gas transducers intended for low concentrations of ozone in air;
– development of proposals on further use of Project results;
– arrangements oriented to the fulfillment of Project objectives and tasks (seminars, report submission to conferences, preparation of report documents, contacts with collaborators, etc.).
The proposed Project completely meets the implementation of prime ISTC objectives and tasks, because it:
– gives the weapons scientists and specialists of Russian Federation, (in particular, to those engaged in the field of the development of weapons of mass destruction, rocket transportation systems), an opportunity to turn to the solution of peaceful problems;
– supports fundamental and applied studies and the development of technologies for peaceful purposes oriented to the creation of new materials and environment control;
– contributes to the solution of national and international engineering problems (in addition to those cited above);
– supports the transition to market economy meeting the civil needs.
The role of foreign collaborators consists in the following:
– direct participation (or participation on consulting level) in statement of theoretical and experimental problems;
– exchange by information in the course of Project implementation;
– commenting of technical reports presented by Project participants;
– participation in routine control of activity under Project;
– arrangement of joint seminars;
– assessment of procedures and technologies developed in the course of Project implementation;
– discussion of the ways of application of Project results to real microsystem productions.
Joint work with foreign collaborators under this Project will positively facilitate the integration of Russian scientists into the world scientific community.
The professional competence of the staff involved in the Project implementation is confirmed by a number of publications issued recently:
1. O.V. Lavrova, P.N. Martynov, Yu.M. Sysoev The Aluminium Oxide Aerogel Production Method. RF Patent №2092437, 1997 (in Russian)
2. R.Sh.Askhadullin, P.N. Martynov, A.A. Simakov, Yu.M. Sysoev. The Aluminium Oxide Aerogel Production Method. Application №98120004 for RF Patent, positive resolution of State expertize for Patent issue of 05.11.1998 (in Russian).
3. R.Sh.Askhadullin, P.N. Martynov, Yu.M. Sysoev et al. The Nontraditional Technology of Aluminium Oxide Monohydrate Aerogel Production and Its Properties. J. «Химия и жизнь - XXI век» (Chemistry and Life - XXI Century) №10, pp 4-7, 1999 (in Russian).
4. R.Sh.Askhadullin, P.N. Martynov, Yu.M. Sysoev et al. The Fundamentals of New Liquid Metal Technology of Nanodispersed Oxide Materials Synthesis (Summary of report published in the Proceedings of conf. « Innovation Development: Achievements of Kaluga Region Scientists», p.136, Obninsk, 1999 (in Russian).
5. R.Sh.Askhadullin, P.N. Martynov, Yu.D. Boltoev et al. «The Physico-Chemical Bases of Aluminium Oxide Aerogels Synthesis and Development of Continuous Technology for Their Production from Ga-Al Liquid Metal System», 1999, 2000.
6. F.Kh. Chibirova, E.E. Gutman //J.The Physical Chemistry, Volume 73, №2, pp. 235-240, 1999 (in Russian).
7. F.Kh. Chibirova, E.E. Gutman //J.The Physical Chemistry, Volume 74, №5, 2000 (in Russian).
8. E.E. Gutman, T.V. Belisheva, F.Kh. Chibirova //Proc. of XI-th European Conference on Solid State Transducers. Warsaw, v.1, p,p, 341-344, 1997 (in English)
9. E.E. Gutman, T.V. Belisheva, S.V. Ryabtsev, F.Kh. Chibirova // Proc. of 6-th Intern. Meeting on Chemical Sensors, Gaitherburg (USA), p. 77, 1996 (in English).
10. Yu.Ya. Tomashpolsky, N.V. Sadovskaya. A Tecnique of Solid Body Analysis. RF Patent №212476, 1999(in Russian).
11. V.I. Kukuev, Yu.Ya. Tomashpolsky et al. A method of Superconductive Metal Oxide Films Fabrication. RF Patent №2037915, 1995(in Russian).
12. V.I. Kukuev, E.A. Sorokina, Yu.Ya. Tomashpolsky et al. The Sedimentation of SnO2 bearing Films with a Given Grain Size. Nonorganic Materials, v. 31, №3, p.p. 342-345, 1995.