Project objective.
· Development of existing space environment simulating facility (Including electron 4 MeV), protons18MeV and solar UV radiations, high vacuum, cryogenic temperatures) of the AANL for in - situ study of the behavior of the materials and devices intended for space applications under conditions modeling the complex exposure of cosmic factors;
· Creating of radiation-resistant semiconductor materials on the basis of III-V semiconductor compounds solid solutions sustaining the large fluxes of hard radiation (1018 particles/cm2) for devices applicable in Space;
· Creating of highly effective, reliable, radiation-resistant experimental samples of Hall-sensors sustaining the large fluxes of hard radiation (1018 particles/cm2) on the basis of III-V semiconductor compounds solid solutions for application in the extreme conditions as the Space, atomic power stations and others.
· The numerical modeling of the electronic structure of III-V semiconductor compounds and Si. The necessity of these calculations is to solve the problem of obtaining of III-V semiconductor compounds and Si materials with predetermined properties. Quantum chemical calculations of III-V semiconductor compounds defects are the powerful tool in determining their optical and electronic properties.
State of the art. It is well known that an object in cosmic space can undergo simultaneous exposure to various factors which can significantly affect its characteristics. In particular, different types of radiation, temperature varied in a wide range, and (in certain orbits in open space), can simultaneously affect electronic devices in space. These circumstances certainly complicate prediction of the behavior of microelectronic devices under space conditions, since estimations are usually being made based on tests in which objects under study are subjected to a single space factor. Significantly more information can be obtained using tests based on facility combining exposure to corpuscular radiation (as a factor undoubtedly affecting all cosmic objects) with other factors listed above. A great experience in this area has Armenian research team.
Semiconductor devices are irreplaceable in the Space. Demands to the semiconductor devices quality for operation in the extreme conditions of hard radiation like Space are more rigid than that for commercial applications. Therefore, these devices have its scientific, technological and specific problems and the list of materials suitable for their manufacturing has a limit. Requirements to existing materials for the present exceed their possibilities. So, for example, silicon (the main material for Photovoltaics) solar cells used in overwhelming majority of the devices have already degraded under small doses of radiation. Long-term investigations carried out by Georgian team, which find a wide international recognition in the world, showed that for these purposes applicable perspective materials may be the III-V semiconductor compounds solid solutions.
The idea of numerical modeling of radiation-resistant materials, implemented by Kazakh team, for application in Space apparatus is a new direction in the world. As used herein, the quantum-chemical calculations certainly have advantages over experimental studies: First - it is an inexpensive tool for the analysis of the influence of defects on the above properties, and secondly - enable us to develop a methodology of experimental research separately selected effect, in the third - allow detailed understanding of the combined effect of a a defect and explain physical, chemical, electronic, and other properties.
It all determines the heightened interest to the problem of creation radiation-resistant semiconductor materials for devices application in Space and other extreme physical conditions and numerical modeling of their optical and electronic structure.
Data on work scope. Within the project the following main works will be performed: development of existing facility for in-situ study of properties of different materials and devices to simulate space factors, study of the effect of various space factors separately and in combination, creation of new radiation-resistant electronic materials for devices operating in the Space; investigating in-situ complex influence of different factors of Space on the properties of experimental samples directly in adequate conditions of Space.
