Registration Number
0212U006376,
0110U006270
, R & D reports
Title
Research and development of ion-plasma technologies for formation of silicon composites at introduction of stimulating self-organization processes impurites.
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Head
Evtukh Anatoli Antonovych,
Registration Date
23-03-2012
Organization
Institute of Semiconductor Physics of National Academy of Sciences of Ukrain
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A report submitted in one volume has pages, including figures 18, tables 3 and references 21. Keywords: nanocrystals, technology, ion-plasma sputtering, tructure, infrared spectroscopy, electrical properties, I-V characteristics, MIS structure. The aim of the project (Phase): The process of self-organizing formation of Si nanoclusters in SiO2 dielectric matrix by high-temperature annealing of silicon-enriched films SiOx. and to establish the basic mechanisms of electron transport through SiO2 (Si) film. The basic laws of transformation of the dielectric matrix- silicon enriched SiOx films during their transformation into a nanocomposite SiO2 (Si) film as a result of high-temperature annealing have been determined. Using the method of IR spectroscopy it was shown that: - After heat treatment at 700 °C the silicon-oxide matrix is nonstoichiometric x <2 and can be represented as a mixture of molecular complexes of Si-Oy-Si4-y (0 ? y ? 4) surrounding amorphous silicon nanoinclusions. - At annealing temperatures 800-1000 °C there is not a complete phase separation in films of SiOx, they consist of phases SiOx, SiO2 and silicon, content of which depends on the annealing temperature and the initial value of stoichiometry index x. - Heat treatment of SiOx films at 1100 °C and above leads to the formation of inclusions of nanocrystalline silicon that is surrounded by SiO2 oxide matrix, whose structure is characterized by a mixture of related 4 - and 6 fold rings of tetrahedra SiO4. Measurement and analysis of current-voltage characteristics revealed that: - The main mechanism of electron transport through the nanocomposite SiO2 (Si) film is a hopping mechanism with a variable hopping length (Mott mechanism). - The conductivity at the same electric field is higher for a film with a high content of silicon, due to a large number of dangling silicon bonds in the film and thinner dielectric sublayers between nanocrystals. - A large excess of silicon leads to a greater number of dangling bonds and defects, in turn, causes the more localized energy states near the Fermi level. - When the temperature decreases the number and energy of the phonon decreases and jumps stimulated by phonon become less likely. For carriers are likely to jump long distances, allowing to get to the nodes that are closer in energy than the distance to nearby neighbors. -The increasing of energy and decreasing of the barrier height for the carriers is realized at increasing the temperature T and field E. That leads to the increase in the concentration of traps N, which are involved in current transport.
Product Description
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Євтух Анатолій Антонович
Лісовський Ігор Петрович
Литовченко Володимир Григорович
Романюк Борис Миколайович
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2020-04-02
