Search results for " semiconductor"
showing 10 items of 332 documents
Thickness-dependent properties of ultrathin bismuth and antimony chalcogenide films formed by physical vapor deposition and their application in ther…
2021
This work was supported by the European Regional Development Fund (ERDF) project No 1.1.1.1/16/A/257. J. A. acknowledges the ERDF project No. 1.1.1.2/1/16/037. Institute of Solid State Physics, University of Latvia, Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017 TeamingPhase2 under grant agreement No. 739508, project CAMART2 . The raw/processed data required to reproduce these findings cannot be shared at this time as the data also form a part of an ongoing study.
Thin Film Organic Thermoelectric Generator Based on Tetrathiotetracene
2017
This is the peer reviewed version of the following article: K. Pudzs, A. Vembris, M. Rutkis, S. Woodward, Adv. Electron. Mater. 2017, 1600429, which has been published in final form at http://onlinelibrary.wi...002/aelm.201600429/full This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
Role of the Back Metal-Semiconductor Contact on the Performances of a-Si:H Solar Cells
2011
We have investigated the role of the metal-semiconductor back contact on the performances of thin film modules consisting of single junction a-Si:H photovoltaic (PV) cells deposited with p-i-n configuration. We find that an adequate choice of the back contact helps reducing the barrier height of the junction improving the contact conductivity. For this purpose Mo has shown to be effective. Moreover we find that Mo, as refractory material, has additional beneficial effects reducing the formation of defects leading to the decrease of recombination losses. We have then fabricated a PV module on flexible substrate for indoor energy harvesting applications using Mo as back contact. An efficiency…
WS2 2D Semiconductor Down to Monolayers by Pulsed-Laser Deposition for Large-Scale Integration in Electronics and Spintronics Circuits
2020
International audience; We report on the achievement of a large-scale tungsten disulfide (WS2) 2D semiconducting platform derived by pulsed-laser deposition (PLD) on both insulating substrates (SrTiO3), as required for in-plane semiconductor circuit definition, and ferromagnetic spin sources (Ni), as required for spintronics applications. We show thickness and phase control, with highly homogeneous wafer-scale monolayers observed under certain conditions, as demonstrated by X-ray photoelectron spectroscopy and Raman spectroscopy mappings. Interestingly, growth appears to be dependent on the substrate selection, with a dramatically increased growth rate on Ni substrates. We show that this 2D…
Characterization and photoactivity of coupled ZnO-ZnWO4 catalysts prepared by a sol-gel method
2014
Abstract ZnO–ZnWO4 nanocomposites were synthesized by a novel sol–gel method and characterized through X-ray diffraction, BET specific surface area analysis, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy and transmission electron microscopy. The photocatalytic activity of the samples was evaluated using the degradation of 4-nitrophenol under UV light as probe reaction. The ZnO/ZnWO4 molar ratio was varied in order to study its influence on the photoefficiency of the mixed samples. The ZnO–ZnWO4 nanocomposites showed higher photoactivity than ZnO and ZnWO4. The high efficiency of the mixed samples was explained by the coupling and the intimate contact of two different…
Impact of Gamma Radiation on Dynamic RDSON Characteristics in AlGaN/GaN Power HEMTs
2019
GaN high-electron-mobility transistors (HEMTs) are promising next-generation devices in the power electronics field which can coexist with silicon semiconductors, mainly in some radiation-intensive environments, such as power space converters, where high frequencies and voltages are also needed. Its wide band gap (WBG), large breakdown electric field, and thermal stability improve actual silicon performances. However, at the moment, GaN HEMT technology suffers from some reliability issues, one of the more relevant of which is the dynamic on-state resistance (R) regarding power switching converter applications. In this study, we focused on the drain-to-source on-resistance (R) characteristic…
On the use of front-end cascode rectifiers based on normally on SiC JFET and Si MOSFET
2014
The new wide band-gap semiconductor devices provide new properties to be explored. Normally on silicon carbide (SiC) JFET power devices have several advantages, in particular low switching losses and the potential capabilities of high temperature and high reverse blocking voltage. Looking for improving the overall efficiency in power converters, new structures based on these power devices might be studied. In this paper, a cascode rectifier based on normally on SiC JFET is presented and analyzed. This rectification structure can be applied as front-end rectifier stage for ac-dc power converters, increasing the overall efficiency of these topologies. A second cascode rectifier based on silic…
A Comparative Performance Study of a 1200 V Si and SiC MOSFET Intrinsic Diode on an Induction Heating Inverter
2014
This paper presents a comparison of the behavior of the intrinsic diode of silicon (Si) and silicon carbide (SiC) MOSFETs. The study was done for 1200 V Si and SiC MOSFETs. The data sheet from manufacturers shows the characteristics of MOSFET' intrinsic diode when gate source voltage (VGS) is 0 V. There are applications where the MOSFET' intrinsic diode is used while VGS is different than 0 V. One of these applications is induction heating, where depending on the load and the regulation system, the diode can conduct a significant part of the inverter current. In most applications which use the MOSFET' intrinsic diode, the turn ON of the intrinsic diode happens at VGS = 0 V. After a blanking…
Structural and electronic properties of InN nanowire network grown by vapor-liquid-solid method
2015
Growth of InN nanowires have been carried out on quartz substrates at different temperatures by vapor-liquid-solid (VLS) technique using different thicknesses of Au catalyst layer. It has been found that a narrow window of Au layer thickness and growth temperature leads to multi-nucleation, in which each site acts as the origin of several nanowires. In this multi-nucleation regime, several tens of micrometer long wires with diameter as small as 20 nm are found to grow along [ 11 2 ̄ 0 ] direction (a-plane) to form a dense network. Structural and electronic properties of these wires are studied. As grown nanowires show degenerate n-type behavior. Furthermore, x-ray photoemission study reveal…
High Temperature SiC Blocking Diodes for Solar Array
2009
This paper presents the results of an experimental investigation of the performance of 300V-5A Silicon Carbide Ni and W Schottky diode operating in the range between -170°C to 270°C. We have developed these diodes as blocking diodes, for solar cell array protection in order to fulfill the BepiColombo mission specifications. An electro-thermal characterization has been performed taking into account the harsh condition of the mission (high temperature range and electrical stress). The destructive and non-destructive tests have assured that the designed SiC diodes are able to support the electro-thermal limits. A reliability test has also been performed to investigate the stability of forward …