For the academic year 2025/2026, the Institute of Electrical Engineering of the Slovak Academy of Sciences (IEE SAS), v.v.i. is announcing the following PhD thesis topics for the study programs:
- Physical Engineering (FEI STU)
- Electronics and Photonics (FEI STU)
- Physics of Condensed Matter and Acoustics (FMFI UK)
Physical Engineering
Topic: Preparation and characterization of Ga2O3-diamond heterostructure UV photodetectors
Supervisor: Ing. Marián Varga, PhD. (Department of microelectronics and sensors)
Description: One of the most significant challenges of the recent years, related to the development of new electronic devices and having potential for major improvement of the current status in a vast variety of human activities can be found in the field of solar-blind (SB) ultraviolet (UV) photodetectors (PDs). Novel UV PDs, especially for deep-UV (DUV) optoelectronics (wavelengths shorter than 280 nm) are needed. These cannot typically be manufactured from conventional materials. This resulted in the development of ultrawide bandgap (UWBG) semiconductors (such as AlxGa1−xN, hBN, Ga2O3, and diamond) and their utilisation for SB UV PDs. Gallium oxide (Ga2O3), a naturally n-type semiconductor, represents a suitable UWBG material, showing a very good potential and capability to significantly improve the current state-of-the-art electronic devices. Furthermore, synthetic diamond has gained a strong reputation to be an exceptionally versatile material due to its attractive physical and chemical properties and availability of facile preparation of films with p-type conduction. On the other hand, it is very difficult to prepare p-type Ga2O3 and n-type diamond.
In this work, we will target the development and detailed characterisation of new high-performance DUV SB PDs with p-n or p-i-n device structure, comprising n– and i-type Ga2O3 and p-type diamond. Such heterostructure devices represent a favorable solution combining the best of the two UWBG worlds. The Ga2O3 layers will be grown by liquid-injection metal-organic chemical vapour deposition (LI-MOCVD), a growth technique developed at IEE SAS. Polycrystalline diamond films will be prepared by MW plasma-enhanced CVD method in close cooperation with the Institute of Physics of the Czech Academy of Sciences in Prague. UV PDs and other electronic devices will be fabricated using modern techniques and tools available at the IEE SAS, i.e. optical or electron-beam lithography, reactive ion etching, and thin films deposition. The designed periodic structures, electric contacts, interdigitated arrays, and van der Pauw test structures will be prepared using a metallic mask prepared by the vacuum sputtering or evaporation through lithographically-prepared masks and patterned by a lift-off process.
The main goal of this PhD thesis is the fabrication, characterisation, and deep understanding of the effects at the Ga2O3-diamond heterostructure interface, and to assess their influence on the properties of such a heterojunction. In addition, focus will be also on testing of the properties of prepared UV photodetectors and their radiation hardness when exposed to the ionising radiation.
Topic: Analysis of the Influence of Doping on the Properties of Ultrathin Layers of Transition Metal Dichalcogenides
Supervisor: Mgr. Michaela Sojková, PhD. (Department of microelectronics and sensors)
Description: The discovery of graphene has sparked extensive research into other 2D materials. Transition metal dichalcogenides (TMDs), with the general formula MX2, where M represents a transition metal (e.g., Mo, W) and X is a chalcogen (S, Se, Te), have gained particular attention. These materials have a layered structure and, depending on their crystalline structure, can exhibit diverse electrical properties (semiconducting, metallic, superconducting, etc.). According to theoretical calculations, TMD materials offer unique characteristics such as high flexibility, enhanced charge carrier mobility, and electronic or optical properties dependent on the number of layers, making them suitable for a wide range of applications. However, many predicted properties of these materials, especially charge carrier mobility, have not yet been experimentally achieved. One approach to improving the electrical properties of 2D-TMDC materials is doping, similar to the doping of semiconductors with desired impurity elements.
This research will focus on the preparation of doped ultrathin TMD layers. A two-step method will be employed, where thin layers of metals or their oxides are first deposited using magnetron sputtering or evaporation. In the second step, these layers will be annealed in the presence of sulfur or selenium vapors (known as sulfurization/selenization) along with the dopant sulfide. The influence of the dopant on the structural, optical, and electrical properties of 2D material layers will be investigated. Various types of TMDs (e.g., MoS2, PtSe2, NbSe2) will be prepared, and multiple metals and their combinations (Ni, Cu) will be used for doping. The prepared layers will be analyzed using X-ray diffraction analysis, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, optical measurements, electrical property measurements, and other characterization techniques. The work will be carried out at the Institute of Electrical Engineering of the Slovak Academy of Sciences (IEE SAS), which is equipped with the necessary technological and characterization facilities. The PhD student will gain versatile skills with numerous experimental methods and will actively participate in collaborations within several projects.
Topic: Electroluminescence of optically-active diamond-based hybrid p-i-n heterostructures
Supervisor: Ing. Tibor Izsák, PhD. (Department of microelectronics and sensors)
Co-advisor: Doc. Ing. Jaroslav Kováč, PhD. (ÚEF FEI STU)
Description: Optically-active diamonds with different colour centres are of great interest for quantum technology, including quantum metrology, information processing, and communication. In order to exploit the promising properties of colour centres in diamond for quantum optical applications, it will be beneficial to manipulate the electronic state of the centres by electric field. Electrical excitability allows overcoming the diffraction limit encountered in optical (laser) excitation, and therefore opens up space for the miniaturization of future devices.
The dissertation is focuses on the research and development of diamond-based field effect transistors (FET) and p-i-n diodes for their opto-electronic characterization. The main task is the design, implementation, and characterization of these devices to study the electrical excitability of luminescence of various color centers in diamond. Electroluminescence measurements will be performed for mono- and polycrystalline diamonds doped with e.g. Si, Ge or Er atoms. In addition, experiments will be carried out to investigate the luminescence properties at different terminations of the diamond surface (hydrogen-, oxygen-, and fluorine-terminations) that affect its charge-state.
The PhD student will be part of a young research team with international collaboration and access to high-tech research facilities. The obtained results may be very desirable for new advanced project proposals (including European ones) and cooperation with companies.
Topic: Study and optimization of detectors of ionizing radiation based on wide bandgap semiconductors as a SiC and diamond
Supervisor: Mgr. Bohumír Zaťko, PhD. (Department of microelectronics and sensors)
Description: The aim of the thesis is the technological preparation of ionizing detectors, the study of electrical and detection properties and the influence of radiation dose on their performance. The detection materials used are high quality epitaxial layers of 4H-SiC, polycrystalline and monocrystalline diamond layers. The work will initially focus on the design and fabrication of detection structures based on Schottky contacts. This will be followed by electrical characterization (current-voltage, capacitance-voltage measurements at different temperatures). SiC and diamond are wide bandgap materials that can operate at elevated temperatures. Selected suitable detection structures will be connected to a low noise spectrometric setup and their properties for particle detection at room and elevated temperatures will be evaluated. Subsequent structures will be irradiated with high doses of electron, proton or neutron-based radiation and their properties after irradiation will be investigated. Finally, the radiation hardness will be evaluated and compared with standard silicon detectors.
The work will be carried out at the Institute of Electrical Engineering Slovak Academy of Sciences, which has modern technological equipment necessary for the preparation and testing of various types of semiconductor structures. The PhD student will acquire knowledge in the preparation of semiconductor detector structures and will be actively involved in teamwork within national and international projects dealing with the preparation and testing of radiation detector structures.
Topic: Electrical transport in thin layers of some TMDC materials
Supervisor: RNDr. Martin Hulman, PhD. (Department of Physics and Technol. at Nanoscale)
Description: In the past two decades, materials characterized by significant dimensional anisotropy have become one of the most extensively studied subjects in solid-state physics and materials research. This category encompasses transition metal dichalcogenides (TMDCs), compounds composed of elements such as S, Se, and Te, in conjunction with metals like Mo, W, and Pt. Substances with the chemical formula MX2 can be synthesized in extremely thin layers.
At the Institute of Electrical Engineering, a team is dedicated to preparing thin layers of TMDC materials and conducting their characterization. The proposed dissertation would complement the endeavors of this group. The focus of the dissertation lies in examining the electrical transport properties of (ultra)thin layers of TMDC materials, particularly those within the subgroup exhibiting semi-metallic and metallic characteristics. The work predominantly entails experimental research. While it entails some involvement in the growth of thin layers, the primary emphasis is on measuring transport characteristics. In addition to transport characterization, the dissertation will explore the impact of temperature, doping, and structure on the conductivity of 2D materials.
Throughout the dissertation, the student will engage with vacuum and low-temperature facilities. The experimental findings will be analyzed in accordance with various models of solid-state physics. Furthermore, the student is expected to present their results at both domestic and international conferences, necessitating proficient spoken and written English skills.
Topic: Artificial magnetic crystals with ferrotoroid order
Supervisor: Mgr. Jaroslav Tóbik, PhD. (Department of Physics and Technol. at Nanoscale)
Description: Current technology allows the production of structures with a resolution of tens of nanometers with good repeatability. This allows the design and implementation of periodically repeating patterns, which defines a crystal. In this way, artificially created crystals can realize the possibilities of structural arrangements and interesting interactions that do not occur in natural materials. A relatively new area of research is artificial crystals from magnetic elements. In some geometries, the so-called ferrotoroidal arrangement has been observed, when the magnetization within the basic cell creates a circulating field. The aim of this work is to investigate theoretically, but also practically, various procedures by which ferrotoroidal arrangement can be achieved in artificial crystals.
Topic: Memristor applications in radiation sensing
Supervisor: Ing. Boris Hudec, PhD. (Department of Physics and Technol. at Nanoscale)
Description: Increasing number of radiation applications across various fields such as medicine, metrology, spectroscopy, etc… as well as the doomsday clock recently adjusted by the Bulletin of the Atomic Scientists to 89s-to-midnight, are both valid reasons to look for new type of simple and cheap radiation sensors. Memristors are simple two terminal electronic devices employing thin dielectric films sandwiched between electrodes whose resistance can be electrically programmed. It has been shown that various types of memristors can be sensitive to various types of ionizing radiation, yet without practical implications. Under this thesis the student will leverage the existing fabrication technology and expertise on memristor devices developed at our Institute for the past decade to study potential applications in radiation sensing. These studies will start with characterization of radiation sensing properties and radiation hardness of different types of memristive devices to different types of ionizing radiation, including studies of underlying physics. Higher goal of the thesis will be to design arrays of memristive sensors for near-sensor or in-sensor computing architectures. The expertise acquired will cover thin film fabrication and patterning techniques, material analyses, electrical characterization and radiation sensing techniques, and basics of hardware neural networks design.
Topic: Fabrication and characterization of Ga2O3-based DUV photodetectors for harsh environments
Supervisor: Ing. Milan Ťapajna, PhD. (Department of III-V Semiconductors)
Co-advisor: Mgr. Iryna Kozak, PhD.
Description: Gallium oxide (Ga2O3) is a new ultrawide bandgap semiconductor material with bandgap energy (Eg) of approximately 5 eV. Owing to negligibly-small energy difference between its direct and indirect bandgap (~50 meV), monoclinic (β) Ga2O3 phase can be considered a direct semiconductor which allows its wide application range in deep UV (DUV) optoelectronics. Potential applications include low-noise solar-blind UV detectors for the industry and defense, radiation-hard sensors for satellite actuators in the open space, or heterostructure scintillation sensors for detection of ionizing radiation.
This thesis will target technology development and electro-optical characterization of simple metal-semiconductor-metal (MSM) DUV photodetectors based on thin Ga2O3 films a new generation of satellite sun sensors for open space, and heterostructure DUV scintillation photodetectors combining n-type Ga2O3 and p-SiC/p-Si for new low-cost detectors of ionizing radiation. PhD student will take part in thin-film growth of Ga2O3 by chemical vapor deposition (CVD), fabrication of test structures and devices by lithography techniques in cleanroom at IEE SAS, testing of their properties incl. their radiation hardness, and design of the electronic readout system. This work will be conducted in the frame of the international project collaboration with the Bolu University (TR) and the involvement of an industrial partner.
Topic: Novel multi-physics modelling methods of superconducting high-field magnets and power applications
Supervisor: Mgr. Enric Pardo, PhD. (Department of Superductors)
Co-advisor: MSc. Anang Dadich, PhD.
Description: High-temperature superconducting electromagnets can generate extremely high magnetic fields beyond 40 T. These magnets enable cutting-edge fundamental research on materials and particle physics experiments, especially when using superconducting accelerator magnets like those in CERN. Superconducting magnets are also very promising for compact fusion reactors for emission-less clean energy and ion propulsion for spacecrafts. Other superconducting power applications can also reduce emissions, such as electric propulsion motors for hydrogen-electric aircraft and high-power wind generators. Designing all these applications require multi-physics computer modelling of their electromagnetic, thermal and mechanical properties. This PhD intends to develop novel multi-physics numerical modelling methods that go beyond finite-element methods in order to speed-up computations, which allows to model more complex devices and obtain novel insights. The newly developed models, which the student will program in C++, will be able to run in supercomputers like Devana in the Slovak Academy of Sciences. The new models will grow from our own software, following our guidance and experience. The student will be able to attend to international conferences in Europe and beyond once a year. This work will be part of our national projects and international collaborations that we gained from European Horizon 2020 projects, such as CNRS (Grenoble, France), CEA (Saclay, France), and HZDR (Dresden, Germany). This PhD joins knowledge from Physics, Engineering, Mathematics and Computational Sciences.
Topic: Study of the magnetization and transport alternating losses in advanced superconductors
Supervisor: Mgr. Ján Kováč, PhD. (Department of Superductors)
Description: Progressive superconductors are usually filamentary composite materials with high current densities and critical temperature (Tc) above 30 K allowing the generation of magnetic fields or the transfer of high electric powers without losses, which allows their effective applications in energy. In spite of large number of existing superconducting materials, there are only few of them with Tc > 30 K and produced in long lengths ~1000 m. There are mostly MgB2 (Tc = 39 K), BSCCO (Tc = 80-103 K) and ReBCO (Tc = 90 K) and these materials are applicable for direct and alternating current conditions. In the case of alternating currents, additional losses are generated in superconducting filaments and also in metallic sheaths, which represents the heating and increased cooling costs. Therefore, presented PhD topic will be focussed to studies of alternating current losses in MgB2 and ReBCO superconductors and simple superconducting coils by magnetization and transport measurements above 20 K and quantifications of basic loss parts (magnetic, coupling and from eddy currents). Obtained experimental results will be correlated with theoretical models and potentially also with simulated results. Present topic will be connected with domestic research projects (APVV) and also within the international, e.g. project SCARLET (Superconducting cables for sustainable energy transition), in which the minimalization of alternating losses is extremely important.
Topic: Two-dimensional sulfides and selenides: Innovative materials for efficient energy storage devices
Supervisor: Mgr. M. Sojková, PhD. (Department of microelectronics and sensors)
Co-advisor: Doc. Ing. Miroslav Mikolášek, PhD. (ÚEF FEI STU)
Description: Rapid technological progress and the growing demand for renewable energy sources require the development of new materials for efficient and reliable energy storage devices. Two-dimensional (2D) materials, such as transition metal chalcogenides based on sulfides and selenides, have shown great promise due to their unique layered structure, high specific surface area, and excellent electrical properties. These materials offer a unique combination of chemical stability, high charge carrier mobility, and the ability to tailor electronic and optical properties through doping or adjusting the number of layers.
This dissertation focuses on the research and development of 2D sulfides and selenides for applications in supercapacitors, lithium-ion batteries, and other energy storage devices. The goal is to understand the impact of chemical composition, structure, and doping on the electrical, electrochemical, and mechanical properties of these materials. The work will include the preparation of powders and thin films of these materials, as well as their characterization using advanced techniques such as X-ray diffraction, Raman spectroscopy, XPS, and electrochemical capacity measurements.
The results of this work will contribute to a deeper understanding of the behavior of 2D materials in electrochemical systems and provide a foundation for the design of new energy storage devices with higher efficiency and stability. These materials may represent an important step toward sustainable and innovative solutions to future energy challenges.
The work will be carried out in collaboration between the IEE SAS and the IEP FEEIT SUT. Both institutions have the necessary technological and characterization equipment. The PhD candidate will acquire versatile skills with a variety of experimental methods and will be actively involved in collaboration within several projects.
Electronics and Photonics
Topic: Vertical GaN MOS structures with semi-insulating channel for high-power switches
Supervisor: : Ing. R. Stoklas, PhD. (Department of III-V Semiconductors)
Co-advisor: Ing. J. Kuzmík, DrSc.
Description: Semi-insulating vertical GaN devices are a class of power semiconductor devices that utilize Gallium Nitride (GaN) material in a vertical configuration, offering significant advantages for high-voltage, high-current, and high-frequency applications. The semi-insulating GaN layer helps to reduce parasitic capacitance, mitigate leakage currents, and improve breakdown voltage, making these devices highly suitable for power electronics, RF amplifiers, and motor drives. By incorporating vertical structures, these devices achieve high current handling capabilities while maintaining efficient thermal management. The combination of GaN’s wide bandgap, high electron mobility, and semi-insulating properties results in improved performance, making vertical GaN devices an ideal choice for next-generation power systems. In vertical devices, it’s crucial to ensure uniform current flow across the entire device area. Structural modifications like current spreaders, channel over-growth or optimized electrode designs help mitigate current crowding effects, improving the channel’s performance. In addition, the channel over-growth process also enhances the interface quality between the gate and the GaN material, which is critical for device reliability and performance. A vertical MOS structure on GaN through channel over-growth is an advanced approach to fabricating high-performance electronic devices. This method involves over-growing a semiconductor layer to form a high-quality gate channel, typically using selective epitaxial growth. The configuration of the semi-insulating vertical GaN transistor designed by us is patented in Slovak Republic; A patent application has also been filed within the EU.
The main aims of the PhD thesis will be an understanding of the basic principles of the GaN vertical structures. Electrical characterization of vertical GaN devices involves assessing key parameters such as breakdown voltage, current-voltage characteristics, capacitance, and on-resistance. These metrics provide insights into the device performance under different operational conditions. High breakdown voltages and low on-resistances are particularly critical for optimizing device efficiency and minimizing energy losses. Mechanisms of failure, including thermal stress, gate oxide breakdown, and defect-related degradation will be also analysed.
Topic: Growth and properties of III-N quantum structures for fast electronics
Supervisor: : Ing. J. Kuzmík, DrSc. (Department of III-V Semiconductors)
Co-advisor: Ing. Stanislav Hasenöhrl, Ing. Michal Blaho, PhD.
Description: Topic of the work deals with the growth and investigations of epitaxial III-N quantum structures prepared by metal-organic chemical-vapor deposition (MOCVD). GaN, as a constituting member of III-N family, is a most dynamically developed material in semiconductor industry marked by a Nobel Prize for invention of blue/white LEDs. Currently, III-Ns attract a lot of interest also for applications in power, high frequency and automotive electronics.
Compounds based on III-N (GaN, AlN, InN) and its combinations facilitate preparation of countless heterostructures showing quantum effects. In particular, 2-dimensional charge carrier gas can be created having high density and mobility, which are crucial aspects for future electronic devices. Similarly, InN represents the material with the highest electron drift velocity among all common semiconductors.
Work will be focused on mastering the growth using the state-of-the-art AIXTRON MOCVD system. Main emphasis will be given to heterostructure quantum wells containing In(Al)N for future ultra-fast transistors, as well as preparation of the channel layer based on InN. Material study will include several techniques for structural, electrical and optical investigations. PhD study will be accomplished by processing and demonstration of test structures and innovative electronic devices.
Topic: Study of transport properties of Ga2O3 transistors for applications in kV range
Supervisor: : Ing. M. Ťapajna, PhD. (Department of III-V Semiconductors)
Co-advisor: Ing. Ondrej Pohorelec, PhD.
Description: Gallium oxide (Ga2O3) is an emerging ultrawide bandgap (UWBG, Eg=4.8–5.3 eV) semiconductor material, recently recognized as a highly promising for high-voltage (HV) and high-power applications. This material can enable solid-state diodes and transistors with unprecedented blocking voltages, far exceeding the capabilities of mature technologies based on main competing compound semiconductors, i.e. GaN and SiC. Ga2O3 devices can thus enable development of systems for transportation utilising electric drive (cars, trains, ships, aircrafts) or transformation for high-voltage DC power distribution networks. Currently, great research effort is focused on growth of Ga2O3 and development of related electronic devices for power applications.
The aim of the work will be the study and detailed characterization of the electrical breakdown of transistors and diodes based on heteroepitaxial Ga2O3 layers prepared at the Institute of Electrical Engineering SAS using chemical vapor deposition methods. The work will be focused on identification of the electrical breakdown modes and description of the breakdown mechanisms in order to propose an optimal design for increasing the blocking voltage of the studied devices. In addition, standard reliability tests (HTRB, HTGB) of the prepared devices will be carried out in order to identify the parasitic instabilities of the electrical device parameters. These results will contribute to the understanding of the specific degradation modes in Ga2O3 power devices and their mitigation.
Topic: Investigating the nucleation mechanisms in III-N and GaO MOCVD growth through in-situ reflectance and machine learning
Supervisor: : Ing. Filip Gucmann, PhD. (Department of III-V Semiconductors)
Co-advisor: Ing. Stanislav Hasenöhrl, Ing. Michal Blaho, PhD.
Description: This PhD thesis aims to explore the nucleation processes during the Metal-Organic Chemical Vapor Deposition (MOCVD) growth of wide and ultrawide bandgap compound semiconductor films based on gallium oxide (GaO) and III-N materials. Nucleation represents a key step in the epitaxial growth which greatly impacts the crystal quality of the subsequently-grown layers and understanding its dynamics can lead to significant advancements in optoelectronic and power device applications. The study will employ in-situ reflectance measurements to monitor the growth process in real-time and will provide a large experimental dataset valuable for understanding various nucleation stages and layer formation. By analysing the reflectance data, PhD student will identify critical parameters and growth process steps affecting the nucleation, e.g. temperature, precursor flow rates, and substrate conditions. Surface morphology, structural and electrical properties will be also analysed to evaluate e.g. rate of coalescence, dislocation density and mobility of charge carriers to support the reflectance-based hypotheses. Machine learning techniques will be integrated to model the complex relationships between varied growth parameters and the resulting reflectance signals. This approach will facilitate the development of predictive models for optimising the MOCVD growth conditions, ultimately leading to improved material quality and more efficient III-N- and GaO-based microelectronic devices.
Physics of Condensed Matter and Acoustics
Topic: Reconfigurable topological magnonic crystal with chiral geometry and its properties
Supervisor: : Mgr. Juraj Feilhauer, PhD. (Department of Physics and Technol. at Nanoscale)
Description: Topological insulators are exciting materials due to their insulating bulk and conductive surfaces/edges. Their surface/edge states are robust against backscattering, making them promising candidates for information carriers in future computing devices. Topological insulators and surface/edge states were predicted and observed in many wave-hosting platforms, e.g. electronic systems, photonic crystals, acoustic crystals, or mechanical crystals. However, there is a lack of results on magnonic topological insulators hosting spin-waves. The main goal of this PhD. thesis is to realize theoretically and numerically 2D topological magnonic crystal that can be reconfigured by a pulse of a uniform magnetic field. Moreover, the geometry of this magnonic crystal will be designed in chiral order enabling the crystal to be topological even without the need of an external out-of-plane magnetic field. Emphasis will be focused on the geometries of crystals that are the most experimentally realizable and corresponding experiments confirming their topological nature will be suggested.
Topic: Study and optimization of detectors of ionizing radiation based on wide bandgap semiconductors as a SiC and diamond
Supervisor: Mgr. Bohumír Zaťko, PhD. (Department of microelectronics and sensors)
Description: The aim of the thesis is the technological preparation of ionizing detectors, the study of electrical and detection properties and the influence of radiation dose on their performance. The detection materials used are high quality epitaxial layers of 4H-SiC, polycrystalline and monocrystalline diamond layers. The work will initially focus on the design and fabrication of detection structures based on Schottky contacts. This will be followed by electrical characterization (current-voltage, capacitance-voltage measurements at different temperatures). SiC and diamond are wide bandgap materials that can operate at elevated temperatures. Selected suitable detection structures will be connected to a low noise spectrometric setup and their properties for particle detection at room and elevated temperatures will be evaluated. Subsequent structures will be irradiated with high doses of electron, proton or neutron-based radiation and their properties after irradiation will be investigated. Finally, the radiation hardness will be evaluated and compared with standard silicon detectors.
The work will be carried out at the Institute of Electrical Engineering Slovak Academy of Sciences, which has modern technological equipment necessary for the preparation and testing of various types of semiconductor structures. The PhD student will acquire knowledge in the preparation of semiconductor detector structures and will be actively involved in teamwork within national and international projects dealing with the preparation and testing of radiation detector structures.
Topic: Electrical transport in thin layers of some TMDC materials
Supervisor: RNDr. Martin Hulman, PhD. (Department of Physics and Technol. at Nanoscale)
Description: In the past two decades, materials characterized by significant dimensional anisotropy have become one of the most extensively studied subjects in solid-state physics and materials research. This category encompasses transition metal dichalcogenides (TMDCs), compounds composed of elements such as S, Se, and Te, in conjunction with metals like Mo, W, and Pt. Substances with the chemical formula MX2 can be synthesized in extremely thin layers.
At the Institute of Electrical Engineering, a team is dedicated to preparing thin layers of TMDC materials and conducting their characterization. The proposed dissertation would complement the endeavors of this group. The focus of the dissertation lies in examining the electrical transport properties of (ultra)thin layers of TMDC materials, particularly those within the subgroup exhibiting semi-metallic and metallic characteristics. The work predominantly entails experimental research. While it entails some involvement in the growth of thin layers, the primary emphasis is on measuring transport characteristics. In addition to transport characterization, the dissertation will explore the impact of temperature, doping, and structure on the conductivity of 2D materials.
Throughout the dissertation, the student will engage with vacuum and low-temperature facilities. The experimental findings will be analyzed in accordance with various models of solid-state physics. Furthermore, the student is expected to present their results at both domestic and international conferences, necessitating proficient spoken and written English skills.
Topic: Growth and properties of III-N quantum structures for fast electronics
Supervisor: : Ing. J. Kuzmík, DrSc. (Department of III-V Semiconductors)
Co-advisor: Ing. Stanislav Hasenöhrl, Ing. Michal Blaho, PhD.
Description: Topic of the work deals with the growth and investigations of epitaxial III-N quantum structures prepared by metal-organic chemical-vapor deposition (MOCVD). GaN, as a constituting member of III-N family, is a most dynamically developed material in semiconductor industry marked by a Nobel Prize for invention of blue/white LEDs. Currently, III-Ns attract a lot of interest also for applications in power, high frequency and automotive electronics.
Compounds based on III-N (GaN, AlN, InN) and its combinations facilitate preparation of countless heterostructures showing quantum effects. In particular, 2-dimensional charge carrier gas can be created having high density and mobility, which are crucial aspects for future electronic devices. Similarly, InN represents the material with the highest electron drift velocity among all common semiconductors.
Work will be focused on mastering the growth using the state-of-the-art AIXTRON MOCVD system. Main emphasis will be given to heterostructure quantum wells containing In(Al)N for future ultra-fast transistors, as well as preparation of the channel layer based on InN. Material study will include several techniques for structural, electrical and optical investigations. PhD study will be accomplished by processing and demonstration of test structures and innovative electronic devices.