A5079177821- Advancements in Semiconductor Devices and Circuit Design
- Semiconductor Quantum Structures and Devices
- Semiconductor materials and devices
- GaN-based semiconductor devices and materials
- Silicon Carbide Semiconductor Technologies
- Radio Frequency Integrated Circuit Design
- Acoustic Wave Resonator Technologies
- Quantum and electron transport phenomena
- Ga2O3 and related materials
- ZnO doping and properties
- Integrated Circuits and Semiconductor Failure Analysis
- Semiconductor Lasers and Optical Devices
- Analog and Mixed-Signal Circuit Design
- Thin-Film Transistor Technologies
- Silicon and Solar Cell Technologies
- Semiconductor materials and interfaces
- Photonic and Optical Devices
- Advanced Thermoelectric Materials and Devices
- Thermal properties of materials
- Electromagnetic Compatibility and Noise Suppression
- 3D IC and TSV technologies
- Near-Field Optical Microscopy
- Superconducting and THz Device Technology
- Molecular Junctions and Nanostructures
- Chemical and Physical Properties of Materials
Central Laboratory of Solar Energy and New Energy Sources
2025
Bulgarian Academy of Sciences
2025
University of Oulu
2008-2015
TU Wien
2004-2014
Slovak Academy of Sciences
2014
Institute of Electrical Engineering of the Slovak Academy of Sciences
2014
Analysis Group (United States)
2008-2010
Physico-Technical Institute
2008
Multimedia University
2008
University of Vienna
2000-2006
Wide bandgap, high saturation velocity, and thermal stability are some of the properties GaN, which make it an excellent material for high-power, frequency, temperature applications. Given predicted wide-spread use, reliable models needed simulationbased optimization. As several application areas require devices to operate at elevated temperatures, a proper modeling dependences band structure transport parameters is highly important. We present two-dimensional hydrodynamic simulations...
Strained-Si material has emerged as a strong contender for developing transistors next-generation electronics, because this system offers superior transport properties. We suggest model describing the low-field bulk mobility tensor electrons in strained-Si layers function of strain. Our analytical includes effect strain-induced splitting conduction band valleys Si, intervalley scattering, and doping dependence. Intervalley scattering been modeled on equilibrium electron distribution valley...
A thorough approach to the investigation of GaN-based high-electron mobility transistors by device simulation is demonstrated. Due structure and material peculiarities, new comprehensive hydrodynamic models for electron are developed calibrated. Relying on this setup, three different independent technologies simulated compared. We further study pronounced decrease in transconductance <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">g</i> <sub...
Hot-electron temperature (Te) in InAlN/GaN high-electron-mobility transistors (HEMTs) was determined using electroluminescence spectroscopy as a function of gate voltage and correlated with the Te distribution by hydrodynamic simulations. Good agreement between measurement simulations suggests that hot electrons can locally reach temperatures up to 30000 K at V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ds</sub> = 30 V, i.e., two three...
A Schottky-barrier normally off InAlN-based high-electron-mobility transistor (HEMT) with selectively etched access regions, high off-state breakdown, and low gate leakage is presented. Metal-organic chemical vapor deposition-grown 1-nm InAlN/1-nm AlN barrier stack capped a 2-nm-thick undoped GaN creating negative polarization charge at GaN/InAlN heterojunction. Consequently, the effective height increased, as well equilibrium carrier concentration in channel decreased. After removal of cap...
Zinc–tin oxide (ZTO) thin films (ZnO)x(SnO2)1−x with different material composition x (0 < 1) are deposited by spin coating on glass substrates at room temperature. The Differential Scanning Calorimetry (DSC) data of the precursor compounds show gradual phase transitions up to 480 °C. These used for an appropriate regime thermal annealing layers. X-ray photoelectron spectroscopy (XPS) mixed compound formation in states Zn2+, Sn4+ and O2- constituents. Optical investigation manifests high...
Direct measurement of the electron velocity vn at an extreme electric field E is problematic due to impact ionization. The dependence vn(E) obtained by a Monte Carlo method can be verified, however, comparing simulated and experimental data on superfast switching in GaAs bipolar transistor structure, which transient very sensitive this high fields (up 0.6MV∕cm). Such comparison allows conclusion made that change from negative positive differential mobility predicted earlier E∼0.3MV∕cm should...
Two quantum-kinetic models of ultrafast electron transport in quantum wires are derived from the generalized electron-phonon Wigner equation. The various assumptions and approximations allowing one to find closed equations for reduced function discussed with an emphasis on their physical relevance. correspond Levinson Barker-Ferry equations, now account a space-dependent evolution. They applied study effects dynamics initial packet highly nonequilibrium carriers, locally generated wire....
An investigation on the field plate technique in AlGaN/GaN power HEMTs is presented. The critical geometrical variables controlling distribution channel are determined and optimized for improved device reliability using two-dimensional numerical simulations. results implemented design of devices fabricated with 600 nm down to 150 gate lengths. Good agreement between experimental simulation data achieved
We present models for the thermal conductivity and specific heat applicable to all relevant diamond zinc-blende structure semiconductors. They are expressed is functions of lattice temperature in case semiconductor alloys material composition.
For the development of next-generation AlGaN/GaN based high electron mobility transistors (HEMTs) in industry, reliable software tools for DC and AC simulation are required. Our device simulator Minimos-NT was calibrated against experimental data this purpose. Subsequently, simulations both scaled devices from same generation new HEMTs were performed. A good accuracy all relevant characteristics comparison to measurement results is achieved.
We experimentally prove the viability of concept double-heterostructure quantum well InAlN/GaN high-electron-mobility transistor (HEMT) for device higher robustness and reliability. In single HEMTs, intrinsic channel resistance increases by 300% after 1 h off-state stress; much less degradation is observed in with an AlGaN back barrier. Physics-based simulation proves that barrier blocks rate carrier injection into buffer. However, whatever design is, energy injected electrons buffer...
Multiple “collapsing” field domains are a physical reason for superfast switching and sub-terahertz (sub-THz) emission experimentally observed in powerfully avalanching GaAs structures. This phenomenon, however, has been studied so far without considering carrier energy relaxation that essentially restricted the possibility of correct interpretation experimental results. Here, we apply hydrodynamic approach accounting non-local hot-carrier effects. The results confirm collapsing domain...
We give an overview of the state-of-the-art heterostructure RF-device simulation for industrial application based on III-V compound semiconductors. The work includes a detailed comparison device simulators and current transport models to be used, addresses critical modeling issues. Results from two-dimensional hydrodynamic simulations heterojunction bipolar transistors (HBTs) high electron mobility (HEMTs) with MINIMOS-NT are presented in good agreement measured data. examples chosen...
We experimentally prove the viability of concept double-heterostructure quantum well InAlN/GaN high-electron-mobility transistor (HEMT) for device higher robustness and reliability. In single HEMTs, intrinsic channel resistance increases by 300% after 1 h off-state stress; much less degradation is observed in with an AlGaN back barrier. Physics-based simulation proves that barrier blocks rate carrier injection into buffer. However, whatever design is, energy injected electrons buffer...