The objective of the study is to provide PhD education to MSc graduates in all partial fields and to create a cross-disciplinary overview of the present development, to develop theoretical foundations in the selected research area, to master the methods of scientific, to develop their creative abilities and to use them for the solution of research problems. This all should lead to a dissertation thesis, which will provide an original a significant contribution to the research status in the field of interest.

Graduates of this program will acquire cross-disciplinary knowledge of and experience in technical and physical subjects on a high-quality theoretical level. Graduates are for their later independent research and development work equipped with the knowledge and experience from, in particular, physics of semiconductors, quantum electronics and mathematical modeling and will be able to independently solve problems associated with nanotechnologies. Potential job careers: research worker in basic or applied research and in the introduction, implementation and application of new prospective and economically beneficial procedures and processes in the field of electronics, electrical engineering, non-destructive testing and reliability and material analysis.

Graduates of this program will acquire cross-disciplinary knowledge of and experience in technical and physical subjects on a high-quality theoretical level. Graduates are for their later independent research and development work equipped with the knowledge and experience from, in particular, physics of semiconductors, quantum electronics and mathematical modeling and will be able to independently solve problems associated with nanotechnologies. Potential job careers: research worker in basic or applied research and in the introduction, implementation and application of new prospective and economically beneficial procedures and processes in the field of electronics, electrical engineering, non-destructive testing and reliability and material analysis

prof. RNDr. Pavel Tománek, CSc.

1. Dielectric properties of insulating vegetable oils for electrical engineering

   The present level of environmental protection as well as current efforts to replace crude oil products by agricultural products exert a strong pressure upon insulating oils used in electrical engineering. The main requirement is improved biodegradability while preserving the standard properties as high breakdown strength, high resistivity, low permittivity, long-term stability as well as low price. These requirements can be met by vegetable oils (e.g. line-seed or rapeseed oils), mostly methylesters or ethylesters, sometimes also triglycerides or their synthetically manufactured analoga. In some cases, a suitable substitute may also be motor and industrial oils. The subject of the study will be dielectric properties of vegetable oils intended for the use in power engineering. Studies should be focused to the impact of a particular chemical structure onto their electrical properties and to their applicability at low temperatures. The work on this topic will require experimental work in sample preparation and design and theoretical studies and measurement of electrical properties of analyzed material systems. What is available: measurement equipment for the frequency range 10^(-3) - 10^9 Hz and the helium cryostat for the temperature range 10 - 500 K.

   Tutor: Liedermann Karel, doc. Ing., CSc.

2. Electrical properties of polydimetylsiloxan - SiO2 systems a the manufacture of composite layers with very low permittivity

   The objective of the research work will be the investigation of electrical properties of polydimetylsiloxan - SiO2 systems and, in particular thin layers made from them. These systems exhibit a very low value of relative permittivity (dielectric constant, < 3,5) and thus they are promising materials for dielectric films for organic this film transistors (OTFT). The research of this topic will require experimental works related to the manufactures of samples, theoretical studies of the behaviour of polydimethylsiloxan - SiO2 systems in electric fields on a microscopic level as well as the measurement of electrical poperties of manufactured samples. Measurements will take place in the laboratory of dielectric relaxation spectroscopy at the Department of Physics, FEEC, BUT Brno, with the available frequency interval 10E-3 - 10E+9 Hz. Also available is a helium cryostat for temperature range 10 - 500 K.

   Tutor: Liedermann Karel, doc. Ing., CSc.

3. Recovery of the original signal shape from the experimentally determined noisy discharge current of a real dielectric.

   The subject of the study and research will be the determination of the true noise-free discharge current from a capacitor containing a real dielectric, and the subsequent Fourier transformation with the objective to find the frequency dependence of the complex permittivity (its imaginary part being often referred to as dielectric spectrum). The focus of the research will be on the processing of a large amount of experimental samples of a noisy discharge current, on the discrimination of noise, its definition and filtration. This part of the work will continue with the Fourier transformation of the denoised discharge current. This part will necessitate a study of the discreet Fourier transformation as well as a selection of a method that will be most suitable for the case of a non-periodical shape of the input function.

   Tutor: Liedermann Karel, doc. Ing., CSc.

4. Study of dielectric and insulating materials with high permittivity

   Materials exhibiting high permittivity (dielectric constant, k) are needed for new applications, particularly in integrated circuits (ICs) using the 32 nm technology and in capacitors. In capacitors, high-k dielectrics will be used in order to attain higher energy densities in capacitors and thus to reduce the size of capacitors themselves. In ICs manufacturing, the present drive toward smaller dimensions results in the thinning of insulating layers, accompanied by an unwanted increase of leakage currents. In order to prevent this effect, higher gate thicknesses are desired which, however, because of the necessity to keep the capacitance constant, should exhibit higher dielectric constant than the pure SiO2. Materials searched for should be used within the current silicon technologies and, therefore, they must be able to sustain all manufacturing steps without being damaged. Materials studied include ZrO2, HfO2, Al2O3, Y2O3, La2O3, Ta2O3 etc. Moreover, all materials considered must be thermodynamically stable on silicon for a long time. The work on this topic will require experimental work in sample preparation and design, studies of the origin of high-k effects and the measurement of electrical properties of material systems developed. What is available: measurement equipment for the frequency range 10^(-3) - 10^9 Hz and the helium cryostat for the temperature range 10 - 500 K.

   Tutor: Liedermann Karel, doc. Ing., CSc.

5. Study of dielectric and insulating materials with low permittivity

   Decreasing the dimensions in integrated circuits (currently 32 nm) brings about an increase of interconnect capacitance and thus the reduction of the signal propagation speed. The limiting factor for a further improvement of electronic device performance thus become not the properties of semiconductor devices themselves but rather interconnect delays and, hence, too high magnitudes of parasitic capacitances. One of the options for the reduction of interconnect capacitances is the reduction of the permittivity (dielectric constant, k) of thin-layer insulating layers (capacitance is directly proportional to permitivity). Two major routes are available: replacement of polar Si-O bonds with less polar Si-F or Si-C bonds or raising the porosity (intentional introduction of air voids). The newly developed low-k materials must, however, not limit the currently used silicon technologies and must be able to pass all manufacturing steps (temperatures up to about 1100°C). The work on this topic will require experimental work in sample preparation and design, studies of the theory of low-k dielectrics and the measurement of electrical properties of developed material systems. What is available: measurement equipment for the frequency range 10^(-3) - 10^9 Hz and the helium cryostat for the temperature range 10 - 500 K.

   Tutor: Liedermann Karel, doc. Ing., CSc.

6. Study of light scattering methods for diagnostics of biological tissues

   Study of structural and optical models of tissues with single and multiple scattering with ordered and randomly distributed scatterers.

   Tutor: Tománek Pavel, prof. RNDr., CSc.