Profile of the branch:|
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.
Key learning outcomes:|
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.
Occupational profiles of graduates with examples:|
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
Issued topics of Doctoral Study Program:|
- Deep neural networks and their usage for defect recognitions on a surface of electronic structure
The work deals with the use of neural networks with deep learning to diagnose the surface of electronic micro and nano structures that are scanned using electron microscopes with varying degrees of resolution. Search for defects occurring on the surface is time-consuming.
- Energy harvesting devices based on lead-free piezoelectric materials
The work deals with design, fabrication and optimization of energy harvesting devices based on piezoelectric materials. The main aim will be focused on lead-free piezoelectric materials such as BCZT, KNN and BNKT. Next part of this work is focused on design of electronics for proposed energy harvester devices with effort to obtain maximal energy transport from energy harvester into an energy storage. Last part is based on proposal and developing of suited methods for testing and evaluation of parameters for piezoelectric energy harvesters.
- Flexible and bulk piezoceramic energy harvesters
The aim of work is to develop new and innovative designs based on millimeter or nanometer piezoceramics for energy harvesters based on mechanical excitations (movement, vibration, motion wind etc.) The individual energy harvesters will be manufactured in a cooperation with selected departments within the university.
- Fluctuation Mechanisms in piezoelectric MEMS based on AlN and ZnO
Aluminum nitride (AlN) and zinc oxide (ZnO) possess physical properties desirable to MEMS designers and researchers for piezoelectric and photonics applications. Compared to AlN, most of the piezoelectric thin film materials are not suitable for the direct integration into silicon-based MEMS devices, because of either incompatibility especially with standard CMOS fabrication processes or require tailored post deposition conditioning steps. But, AIN offers only moderate piezoelectric coefficients. For many applications such a large response is, however, not required; as its strong crystal qualities allow for very sensitive devices with high quality factors. Because of its low dielectric losses and high breakdown field, the figure of merit for AlN transducers can be about 24 times higher than comparable PZT transducers.
The thesis aims to identify significant fluctuation mechanisms in AlN-based piezoelectric MEMS as well as to optimize signal-to-noise ratio of these devices. Noise measurements and piezoelectric/electric characterizations will be provided at a wide temperature range from 80 K up to 400 K. Aging tests will be provided for analysis of degradation parameters (humidity, IR radiation, temperature). Also optical/electronic microscope analysis will be involved to verify the proper dimension and morphology. Besides AlN, zinc oxide (ZnO) is an attractive alternative due to enhanced piezoelectric properties and will also be investigated within this thesis.
The study will be carried out on AIN and ZnO thin layers deposited on electrodes of different material (silver, platinum, gold, etc.), which will be prepared in cooperation with Vienna University of Technology. It is expected that Phd student will stay at cooperating laboratory for mid-term stay.
- Methods for precise 3D distance measurement
Size measurement of the object is becoming important together with progress of 3D printing technology, augmented reality, navigation systems and various portables devices. There exist several approaches for distance measurement suitable for particular applications with different resolution, measurement range and speed of measurement. The work will be focused on possibilities of particular method utilization.
- SPM – based surface engineering
The properties of materials in the micro- and nano-scale can be dominated by the geometry of the surface, and, in such cases, will therefore be a function of the dimensions. There many classes and modifications of SPM, as many scanning modes and methods have been invented. Nevertheless, there is still a large unstudied potential for the use of SPM for both preparation and investigation of structures at nanoscale. SPM measurements allow evaluation of surface parameters with a high degree of precision. SPM lithographic techniques are capable of making nanometric scale features. Lithography can be carried out by using force or electric interaction between the sample surface and the probe. When the tip is in a contact with the surface, structures are created by elastic and plastic deformations of the material. For electric lithography, modifications are achieved by changes in the material conductivity and humidity during anodization, which strongly affect the processed and thus should be controlled. The purpose of this study is surface modification by SPM techniques (anodic oxidation, force lithography) and characterization of the prepared structures.
- Stability of photovoltaic heterostructures
Study of stability of semiconductor structure influences both the design of new structures and performance of existing electronics. This work is supposed to contain degradation tests and consequent characterization of the test structures. Phenomena of photovoltaic heterostructures are of interest for both fundamental physics and practical applications. Purpose of this work is study of induced aging process of photovoltaics heterostructures.
- Study of resistance drift of high voltage heaters, proposal of model, methods of drift reduction
The aim is to study the degradation processes in high-voltage heaters for electric vehicles. Secondary targets include the proposition of model and methods of resistence drift reduction. This work will be carried out in cooperation with the multinational company where doctoral student completes an internship (in the Czech Republic or Austria).
- Utilization of electromagnetic emission for monitoring of processes in rocks
Electromagnetic emissions (EME) arises during mechanical loading of solids. EME anomalies under natural conditions can be observed in association to tectonic loading, stress re-distribution and crack propagation prior to earthquake or in relation to gravitational mass movements. EME can be measured by various types of antennas and it is possible to perform monitoring of the above mentioned phenomena based on this measurement.
The goal will be development of a methodology for measuring and processing of EME for use in predicting of earthquakes and other selected events and possibly to distinguish between different types of these phenomena. Long-term measurements of EME in caves in the Czech Republic and in the Alps in Austria will be carried out for this purpose and the results will be compared with results from other methods used in geology. Analysis of EME signals origin and propagation in studied materials and design and verification of advanced methods for measured signals processing and evaluation will be an important part of the work.
The Ph.D. student will cooperate on the scientific research collaboration with the Institute of Rock Structure and Mechanics of the ASCR.