A5024595052- GaN-based semiconductor devices and materials
- Semiconductor materials and devices
- Advancements in Semiconductor Devices and Circuit Design
- Ga2O3 and related materials
- ZnO doping and properties
- Semiconductor Quantum Structures and Devices
- Analytical Chemistry and Sensors
- Conducting polymers and applications
- Gas Sensing Nanomaterials and Sensors
- Metal and Thin Film Mechanics
- Semiconductor Lasers and Optical Devices
- Radio Frequency Integrated Circuit Design
- Nanowire Synthesis and Applications
- Electrochemical sensors and biosensors
- Transition Metal Oxide Nanomaterials
- Silicon Nanostructures and Photoluminescence
- Semiconductor materials and interfaces
- Acoustic Wave Resonator Technologies
- Ferroelectric and Negative Capacitance Devices
- Thermal Radiation and Cooling Technologies
- Photocathodes and Microchannel Plates
- Mechanical and Optical Resonators
Linköping University
2021-2023
University of Iceland
2022
Polar Light Technologies (Sweden)
2022
Japan Advanced Institute of Science and Technology
2014-2018
The hot-wall metal-organic chemical vapor deposition (MOCVD), previously shown to enable superior III-nitride material quality and high performance devices, has been explored for Mg doping of GaN. We have investigated the incorporation in a wide range (2.45×1018 cm−3 up 1.10×1020 cm−3) demonstrate GaN:Mg with low background impurity concentrations under optimized growth conditions. Dopant levels are discussed view Ga supersaturation, which provides unified concept explain complexity...
We have investigated insulator-semiconductor interface fixed charges in AlGaN/GaN metal-insulator-semiconductor (MIS) devices with Al2O3 or AlTiO (an alloy of and TiO2) gate dielectrics obtained by atomic layer deposition on AlGaN. Analyzing insulator-thickness dependences threshold voltages for the MIS devices, we evaluated positive charges, whose density at AlTiO/AlGaN is significantly lower than that Al2O3/AlGaN interface. This a higher dielectric constant lead to rather shallower Al2O3....
We have systematically investigated low-frequency noise (LFN) in AlN/AlGaN/GaN metal-insulator-semiconductor (MIS) devices, where the AlN gate insulator layer was sputtering-deposited on AlGaN surface, comparison with LFN AlGaN/GaN Schottky devices. By measuring ungated two-terminal devices and heterojunction field-effect transistors (HFETs), we extracted characteristics intrinsic gated region of HFETs. Although there is a bias regime Schottky-HFETs which dominated by leakage current,...
Using aluminum titanium oxide (AlTiO, an alloy of Al2O3 and TiO2) as a high-k gate insulator, we fabricated investigated AlTiO/AlGaN/GaN metal-insulator-semiconductor heterojunction field-effect transistors. From current low-frequency noise (LFN) characterization, find Lorentzian spectra near the threshold voltage, in addition to 1/f for well-above-threshold regime. The are attributed electron trapping/detrapping with two specific time constants, ∼25 ms ∼3 ms, which independent length...
We have systematically investigated low-frequency noise (LFN) in InAs films with several thicknesses (≃10-100 nm) bonded on low-k flexible substrates (InAs/FS), comparing that epitaxially grown GaAs(001) (InAs/GaAs). obtain current LFN spectra exhibiting approximate 1/f characteristics and consequent effective Hooge parameters α depending the thickness, where we find InAs/FS is larger than InAs/GaAs. The behavior of can be attributed to fluctuation electron mobility dominated by...
GaN-based pyramidal quantum structures, InGaN nanostructures located on top of micro-sized GaN pyramids, were fabricated by selective-area growth SiC substrates means hot-wall metal-organic chemical vapor deposition. Arrays structures exhibit micro-size pyramids possessing high uniformity, precise hexagonal bases, and InGaN/GaN quantum-well layers with well-defined interfaces. Each pyramid comprises a p-i-n structure, which is separated from that other dielectric layer, serving as building...
Electron transport properties in InAs films epitaxially grown on GaAs(001), InAs/GaAs(001) heterostructures, were systematically investigated through the dependence crystal direction, thickness, and temperature. As a result, we found pronounced electron mobility anisotropy, which is highest lowest along [11¯0] [110] directions, respectively. The anisotropy intensifies as thickness decreases, while it diminishes thick regimes, where are relatively immune to effects from epitaxial...
We fabricated and investigated an InAs/high-k/low-k structure in comparison with InAs/low-k structure, where the former latter are respectively obtained by bonding of InAs/Al2O3/AlN InAs on low-k flexible substrates (FS). The (InAs/Al2O3/AlN/FS) exhibits electron mobilities immune to interface fluctuation scattering, whereas this scattering is serious for (InAs/FS). Moreover, we find that sheet concentrations significantly higher than those InAs/low-k. From InAs/Al2O3 analysis...
We investigated low-frequency noise (LFN) in InAs films with several thicknesses (~ 10-100 nm) bonded on flexible substrates (InAs/FS) or epitaxially grown GaAs(001) (InAs/GaAs). The exhibit current LFN 1/f <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">β</sup> spectra, where we obtain thickness-independent exponents β = 1.26 and 1.03 for InAs/FS InAs/GaAs, respectively. thickness independence of the is owing to fact that dominated by...
Using aluminum titanium oxide (AlTiO, an alloy of Al2O3 and TiO2) as a high-k gate insulator, we fabricated investigated AlTiO/AlGaN/GaN metal-insulator-semiconductor heterojunction field-effect transistors. From current low-frequency noise (LFN) characterization, find Lorentzian spectra near the threshold voltage, in addition to 1/f for well-above-threshold regime. The are attributed electron trapping/detrapping with two specific time constants, ∼25 ms ∼3 ms, which independent length...
We investigated the electron transport properties of n-GaN under an Ohmic-metal. Hall measurement results were compared for (A) before Ti-based metal deposition, (B) after deposition but annealing, (C) Ohmic and (D) Ohmic-metal removal, where multi-probe-Hall device measurements are required (C), while others, (A), (B), (D), can be characterized by conventional measurements. The elucidated that, Ohmic-metal, concentration is increased mobility enhanced in comparison with those other cases,...
2018 International Conference on Solid State Devices and Materials,Threshold Voltages of AlGaN/GaN Metal-Insulator-Semiconductor Depending Al<i><sub>x</sub></i>Ti<i><sub>y</sub></i>O Gate Insulator Compositions
The hot-wall metal-organic chemical vapor deposition (MOCVD), previously shown to enable superior III-nitride material quality and high performance devices, has been explored for Mg doping of GaN. We have investigated the incorporation in a wide range ($2.45\times{10}^{18}~cm^{-3}$ up $1.10\times{10}^{20}~cm^{-3}$) demonstrate GaN:Mg with low background impurity concentrations under optimized growth conditions. Dopant levels are discussed view Ga supersaturation which provides unified...