Pure Materials from Semiconductor Waste
Development of Ecologically Safe Technologies for the Production of High Purity Materials (Gallium, Germanium, Arsenic) from Semiconductor Industry Waste
Tech Area / Field
- MAN-MAT/Engineering Materials/Manufacturing Technology
- CHE-IND/Industrial Chemistry and Chemical Process Engineering/Chemistry
3 Approved without Funding
State Research Institute of Organic Chemistry and Technology, Russia, Moscow
- Institute of General and Inorganic Chemistry (IONKh), Russia, Moscow\nFirm A and K - Human Ecology Center, Russia, Kaluga reg., Kaluga
- Swedish Corrosion Institute, Sweden, Stockholm\nCNRS / Institut de Chimie de la Matière Condensée de Bordeaux, France, Pessac\nUniversity of Leoben, Austria, Leoben
Project summarySemiconductor industry based on gallium phosphide and gallium arsenide and germanium is rapidly developed. A twofold growth in the world output of these products, being observed during the last decade, confirms this fact. However, the considerable increase of the output of gallium-, germanium- and arsenic-containing materials was accompanied by an extremely disturbing situation, connected with the utilization of the starting raw materials in semiconductor industry. Production of the most promising up-to-date semiconductors is known to be based on using of high ($ 600ё800, $ 1,000ё1,600 and $160ё200 per kg, respectively). At the same time the efficiency of using raw materials in manufacturing integrated microcircuits, solar batteries and the like is rather low (in some cases below 10%). The matter is that because of the complexity and multistage character of electronics production the main part of gallium, germanium and arsenic remains in waste both in the production of semiconductor ware (ignot cutting, grinding, polishing, etching etc.) and as a result of rejection them at all production stages. Toxic waste are mainly buried, that leads to the ecological load on biosphere.
Arrangement of the complex processing of semiconductor industry waste into high pure gallium, germanium and arsenic for electronics appears to be the most promising solution of the raw materials problem in the semiconductor industry. In fact, the implementation of this approach will result in the occurrence of the new raw material source for extensively developing production of semiconductors based on gallium arsenide, gallium phosphide and germanium. The stringent necessity of the approach is obvious from both economic (reducing production costs, increasing the efficiency of using of the deficient raw components) and ecological (lowering of technological load on the environment) points of view. Therefore, the main aim of the proposed Project is to develop the scientific basis for ecologically safe deep processing of semiconductor industry waste into high purity gallium-, germanium- and arsenic-containing materials. The realization of the project results will allow to increase substantially the economical efficiency of the production of materials for electronics since using waste as more concentrated raw materials compared with the natural raw materials will result in decrease of the net cost of the semiconductor products. For instance, preliminary calculations show that the expenditures for the production of high purity gallium and germanium from semiconductor industry waste are considerably (1.5 times) lower than that at the enterprises dealing with the traditional technologies.
A group of the experienced scientists from the State Unitary Enterprise “State Research Institute of Organic Chemistry and Technology” (SUE GosNIIOKhT), Kurnakov Institute of General and Inorganic Chemistry Russian Academy of Sciences (IGIC RAS) and Closed-type Joint Stock Company “Firm A and K” – “Human Ecology” Center (FCH) appears to be an assurance of the successful fulfillment of the Project. The project participants were engaged formerly in the development of the lewisite destruction technology (along with synthesis and studying of properties) as well as in the processing of toxic waste from non-ferrous metal industry into high purity arsenic materials (ISTC project No. 1020-98). Besides that they made a considerable theoretical and practical contribution to the arrangement of the production of gallium, germanium and arsenic materials for electronics, and published a number of patents and papers in Russian editions.
The implementation of this Project would result in the following:
– improvement of the environmental conditions in the regions of location of the semiconductor industry enterprises; scientific and technical basis for the necessity of a decrease of seized land, used for storage of waste from semiconductor industry (ecological);
– the techniques of gallium, germanium and arsenic extraction from semiconductor industry waste and purification of the raw materials (scientific);
– increase of the technical economic indices of the production of Ga-, Ge- and As-containing semiconductors; and formation of the new raw material resource (waste from semiconductor production) for obtaining of high pure germanium, gallium and arsenic (economic);
– the modernized technologies for deep processing of semiconductor industry waste into raw gallium, germanium and arsenic and their compounds; development of the production of high purity (6N and 7N purity) gallium-, germanium – and arsenic-containing compounds from semiconductor industry waste (industrial);
– intellectual property objects (patented inventions) and know-how in the course of the Project fulfillment (commercial).
Conditions, providing subsequent entering of the proposed Project participants the market of the scientific and technical production and applying the developed technologies, appear to be the perspective aim of this Project.
The proposed project meets the ISTC goals and objectives, since it:
– facilitates to pert SUE GosNIIOKhT to a modern scientific center on the development of technologies for processing industrial waste and to redirect a group of highly skilled scientists and engineers, formerly engaged in the field of chemical weapons, to peaceful activity;
– is directed to creation of the scientific and technical basis for lowering of technological load on biosphere and for the development of technologies for producing of high purity germanium, gallium phosphide and gallium arsenide from semiconductor industry waste, used in solar power engineering, micro- and optoelectronics;
– is characterized by a high commercial significance, and its expected results are anticipated to be commercial;
– stimulates gradual integration of Russian specialists-participants in the Project with international scientific and industrial community due to the intense interest of scientists and industrialists all over the world in the problem of extension of raw material resource base for the production of gallium-, germanium- and arsenic-based semiconductors.
To reach the main goal of this Project it is proposed to carry out a complex of interrelated theoretical and experimental studies, including:
– selection of the main subjects for scientific investigation among common gallium-, germanium- and arsenic-containing waste; analysis of scientific and technical information on the waste formation ways; their classification and certification; development of analytical methods for controlling the composition of toxicants;
– development of methods for waste dearsenization from the production of gallium arsenide and semiconductor devices on its base;
– working out of technologies for producing raw gallium, germanium and arsenic as well as their compounds from waste from the production of gallium phosphide and germanium semiconductors;
– development of methods for deep purification of raw gallium, germanium, and arsenic, extracted from semiconductor production waste;
– development of technologies for obtaining of high purity (6N and 7N purity) gallium-, germanium- and arsenic-containing compounds for microelectronics, optoelectronics and solar power engineering on the basis of the new raw material resources (semiconductor production waste).
The following foreign scientists are suggested to be engaged in the Project fulfillment as foreign collaborators:
1. Prof. Paul Hagenmuller, (ICMCB-CNRS University, Bordeaus, France).
2. Dr.-Ing. Vladimir Kucera, (Swedish Corrosion Institute AB, Sweden).
3. Prof. Dr. Wolfhard Wegscheider, (University of Leoben, Austria).
The cooperation with the above collaborators within the framework of this Project will be carried out in the following directions:
– consultations on different aspects of the Project and information exchange on scientific research results;
– holding joint scientific seminars;
– joint discussions of the collaborators’ comments on annual reports and the final report submitted to the ISTC;
– participating in the work of the commission of experts on the assessment of technologies developed during the Project fulfillment;
– contribution to the commercialization of the scientific and technical developments worked out in the course of the Project fulfillment.
It is suggested that this Project should be carried out on the basis of the scientific and technical potential of the leading scientific schools of SUE GosNIIOKhT, IGIC RAS and FCH, as well as personal experience of specialists - Project participants. The complex character, the completeness and ecological trend appear to be the peculiar features of the Project. The systematic approach, considering chemical technological process as the complicated system of the correlated subsystems, each of which has its own hierarchical structure, was chosen as the basis for the solution of the stated problems. For this reason the Project includes three interrelated parts (subsystems). At the first stage the research on the dearsenization process of gallium-, germanium- and arsenic-containing waste from semiconductor industry resulting in obtaining of raw components (gallium, germanium, arsenic and their compounds) is supposed to be carried out (the 1st subsystem). Both pyrometallurgical (distillation, high temperature liquid extraction, sorption extraction and chemical precipitation from melts) and hydrometallurgical (leaching, crystallization and electrochemical precipitation, sorption and extraction from aqueous solutions, reduction-oxidation) methods of extracting components from solid and liquid products would be applied.
The optimum operating conditions could be determined, ecological safety problems could be solved, and technological schemes for the most promising processes of deep waste recovery from semiconductor industry could be worked out later on. In other words, at the second stage of the Project the scientific basis for the technologies of producing of commercial gallium, germanium, arsenic, and their compounds, based on the new raw material source, are going to be developed (the 2nd subsystem). The research, concerning this part of the project, would be carried out in GosNIIOKhT.
Methods for deep purification of raw materials (gallium, germanium, and their compounds), extracted from semiconductor industry waste, would be worked out and technologies for obtaining of high purity gallium-, germanium- and arsenic-containing compounds for microelectronics, optoelectronics, and solar power engineering would be developed at the final stage (the 3d subsystem). The research, concerning this part of the project, would be carried out in IGIC RAS and FCH. Obviously, specific scientific and technical approaches and methods would be applied at every stage of the research work to solve the project problems. In this connection to reach the main aim of the Project it seems to be reasonable:
– to take into account specific character of semiconductor industry enterprises;
– to optimize both each technological stage and the process in general, applying mathematical design of the experiment and the theory of similarity;
– to solve the problem of the ecological safety for each technological stage applying “low-waste” and “recycling of reactionary mass” principles;
– to extract gallium, germanium, and arsenic from semiconductor industry waste with a high (95% to 99%) extraction ratio;
– to establish a correlation of nature, composition, origin of waste and the quality of the target products – high purity Ga, Ge, and As;
– to develop further the idea of stabilization of chemical forms of microimpurities as applied to the problems of GeCl4 and AsCl3 production based on the new raw material source while solving the 3d subsystem problems.
To realize this approach the following up-to-date physical chemical methods for research of solid state compositions would be applied:
– fluorescence X-ray analysis (IGIC RAS) and X-ray diffraction analysis (IGIC RAS);
– inductively coupled plasma mass spectroscopy (FCH), atomic emission spectroscopy with spectrum exciting in direct current arc (FCH).