| title: | Non-Impact Mechanisms of Defect Creation in Metal Oxides and Fluorides |
|---|---|
| reg no: | ETF6652 |
| project type: | Estonian Science Foundation research grant |
| subject: |
1.3. Physics |
| status: | accepted |
| institution: | Institute of Physics at University of Tartu |
| head of project: | Aleksandr Luštšik |
| duration: | 01.01.2006 - 31.12.2008 |
| description: | The development of various technology fields - short-wavelength nanophotolithography, TV plasma display panels and especially thermonuclear energetics - is limited by insufficient radiation resistance of different construction materials. Further scientific investigation of the fundamental processes of the creation of nano-defects and their associations is needed to solve the extremely difficult task of the decreasing of the efficiency of the creation and stabilization of radiation defects in solids. The main aim of the project is to separate and investigate the novel non-impact creation mechanisms of nano-scale defects due to the recombination of non-relaxed (hot) electrons and hot holes or due to the decay of a cation excitons, the energy of which exceeds the energy gap by several times and is sufficient to create a group of spatially correlated excitations, in some wide-gap metal oxides and fluorides. The complex study of these novel mechanisms of defect creation in pure and doped wide-gap dielectrics (MgO, SiO2, LiF, Li4SiO4, Al2O3, aluminates) will be conducted under irradiation by photons of 6-1000 eV, electrons of 1-300 keV (steady an pulse regime) and swift ions. Radiation defects will be detected by means of low-temperature VUV-XUV spectroscopy methods, EPR and earlier elaborated by us highly sensitive luminescent methods of thermoactivation spectroscopy. A possibility of “luminescent defence” of doped materials against the process of defect creation will be tested. In our opinion, the efficiency of defect creation by hot recombination can be significantly depressed (or even totally suppressed) due to the efficient energy transfer of hot carries to impurity luminescence centres (such transfer processes we revealed in our previous studies). In collaboration with theorists, the energetic and other criteria of the radiation resistance of dielectrics will be generalized. The novel prospects of increasing the radiation resistance of materials against non-impact processes in wide-gap dielectrics with wide and complex valence band will be analysed. |
| project group | ||||
|---|---|---|---|---|
| no | name | institution | position | |
| 1. | Vigen Issahhanjan | |||
| 2. | Aleksei Kotlov | |||
| 3. | Irina Kudrjavtseva | |||
| 4. | Tiit Kärner | |||
| 5. | Aleksandr Luštšik | Tartu Ülikooli Füüsika Instituut | ||
| 6. | Vitali Nagirnõi | |||
| 7. | Jevgeni Vassiltšenko | |||