The Photoluminescence Spectra Of Powders Of Zinc Oxide With Laser Excitation,
2019
Institute of Semiconductor Physics and Microelectronics at the NUUz. Tashkent, Uzbekistan
The Photoluminescence Spectra Of Powders Of Zinc Oxide With Laser Excitation, Ilyos A. Rakhmatullaev, Vladimir S. Gorelik, Abdulla K. Kurbonov
Euroasian Journal of Semiconductors Science and Engineering
The original sensitive method of research of the nanopowders based on use of laser excitation and a multichannel spectrometer is offered. The developed method can be used for the analysis of quality of a wide class of the powders on the basis of laser spectroscopy of secondary radiation.
Organic Photodiodes On The Basis Of Cotton
Fiber/Polymer Composite,
2019
Institute of Semiconductor Physics and Microelectronics at the NUUz, Tashkent, Uzbekistan,
Organic Photodiodes On The Basis Of Cotton Fiber/Polymer Composite, Jonibek J. Hamdamov, Anvar S. Zakirov, Abdugafur T. Mamadalimov
Euroasian Journal of Semiconductors Science and Engineering
In this paper, we report a study on the optical and the electrical properties of pure cotton fibers (CF) from chemically surface- and morphology-modified samples coated with poly [2-methoxy-5-(2-ethylhexyloxy)- 1,4-phenylenevinylene] (MEH-PPV) polymer by using a dip-coating method. The efficiency of white light luminescence of cotton fibers coated with meh- MEH-PPV polymer increased and became much more intense in comparison with the luminescence of uncoated fibers and blue, green and red stripes were observed in the luminescence structure. The сurrent-voltage characteristic of sandwich-type devices consisting of successive layers of ITO (Indium doped tin oxide coated glass)-PEDOT-PSS (Poly (3,4-ethylenedioxythiophene)-Poly(styrenesulfonate)-CF/MEH-PPV-Ag showed that up …
Radiation And Convective Losses In The Heat Sink Channel Of Photovoltaic-Thermal System,
2019
Institute of Semiconductor Physics and Microelectronics at the NUUz, Tashkent, Uzbekistan
Radiation And Convective Losses In The Heat Sink Channel Of Photovoltaic-Thermal System, Oskar F. Tukhfatullin, Ramizulla A. Muminov
Euroasian Journal of Semiconductors Science and Engineering
. The processes of heat transfer in the channel of a liquid photovoltaic/thermal system of a flat construction without forced circulation are considered. A method of calculating the heat transfer coefficients by radiation and convection, the Nusselt and Reynolds numbers for a given photovoltaic/thermal system was proposed. It was determined that the processes of convective heat transfer in a flat photovoltaic/thermal system installed in the territory of the Republic of Uzbekistan at an optimum angle of inclination equal to the geographical latitude of the place of operation should be considered as for parallel plates located at tilt angle not more …
Serial And Shuntable Resistance Of Cigs Solar Photo-Electric Module In The Conditions Of Real Solar Lighting At Various Temperatures,
2019
International Solar Energy Institute, Tashkent, Uzbekistan
Serial And Shuntable Resistance Of Cigs Solar Photo-Electric Module In The Conditions Of Real Solar Lighting At Various Temperatures, Rustam R. Kobulov, Nuriddin A. Matchanov, Omonboy K. Ataboev, Farrukh A. Akbarov
Euroasian Journal of Semiconductors Science and Engineering
The current-voltage characteristics of the solar photovoltaic module, based on a thin-film polycrystalline semiconductor binary compound Cu(In, Ga)Se2, under real solar illumination (Prad=780 ± 30 W/m2), in the temperature range of 25 °C-50 °C, have been studied and the values of serial and shunt resistance are determined. It has been established that with increasing temperature, the magnitudes of the series and shunting resistance of the solar photovoltaic module decrease, which is most likely due to the modulation of the resistance of the n-CdS buffer front layer.
Influence Of Heat Treatment On The Behavior
Of Deep Levels In Silicon Doped By Tungsten,
2019
Institute of Semiconductor Physics and Microelectronics at the NUUz., Tashkent, Uzbekistan
Influence Of Heat Treatment On The Behavior Of Deep Levels In Silicon Doped By Tungsten, Shokhrukh Kh. Daliev, Abdugofur T. Mamadalimov, Sayfullo S. Nasriddinov, Anifa D. Paluanova
Euroasian Journal of Semiconductors Science and Engineering
By means of Deep Level Transient Spectroscopy the kinetics of the annealing of the levels of tungsten in silicon during heat treatment in the temperature range 150÷4000С was studied. It was found a non-monotonic change in the concentration of deep levels Ec-0.30 eV and Ec-0.39 eV under isothermal annealing: the concentrations of both levels at short times increase, then the concentration level of Ec-0.30 eV sharply decreases, and the reduction of the concentration of deep level Ec-0.39 eV is much slower.
Infrared Spectroscopy Of Silicon Doped By Stannum
And Manganese,
2019
Institute of semiconductor physics and Microelectronics at the NUUz., Tashkent, Uzbekistan
Infrared Spectroscopy Of Silicon Doped By Stannum And Manganese, Sharifa B. Utamuradova, Ravshanbek M. Ergashev, Khusniddin J. Matchanov
Euroasian Journal of Semiconductors Science and Engineering
The processes of defect formation in silicon doped by tin and manganese and their interaction with uncontrolled impurities were studied by infrared spectroscopy.It was found that the presence of impurities of transition and isovalent elements leads to a technological decrease in the concentration of process impurities – oxygen and carbon. It was found that the introduction of manganese in Si leads to a strong decrease in the concentration of interstitial optically active oxygen Noopt: in rapidly cooled samples Si there is a decrease of Noopt by 50% compared to the original Si.
Structural Features Of The Solid Solution (Gaas)1-X-Y(Ge2)X(Znse)Y With Quantum Dots (0≤X≤0,17; 0≤Y≤0,14),
2019
Andijan State University. Andijan, Uzbekistan.
Structural Features Of The Solid Solution (Gaas)1-X-Y(Ge2)X(Znse)Y With Quantum Dots (0≤X≤0,17; 0≤Y≤0,14), Sirojiddin Z. Zainabidinov, Khatamjon J. Mansurov, Akramjon Y. Boboev, Hkushruy A. Makhmudov
Euroasian Journal of Semiconductors Science and Engineering
X-ray diffraction studies showed that the resulting film has a sphalerite structure and is single-crystal with the (100) orientation. The lattice parameter of the film is af = 0.56697 nm. By atomic force microscope was shown the possibility of obtaining a semiconductor heterostructure with quantum dots by the method of liquid phase epitaxy.
Study Of The Morphological And Electrical Properties Of Films Of Solid Solution Znxsn1-Хse Obtained
By The Method Of Cmbd,
2019
SPA «Physics-Sun» of the Academy of Sciences of the Republic of Tashkent, Uzbekistan.
Study Of The Morphological And Electrical Properties Of Films Of Solid Solution Znxsn1-Хse Obtained By The Method Of Cmbd, Kudrat M. Kuchkarov, Takhir M. Razykov, Bobur A. Ergashev, Rukhiddin T. Yuldoshov
Euroasian Journal of Semiconductors Science and Engineering
The ZnXSn1-XSe solid solution films were fabricated by the chemical molecular beam deposition (CMBD) method. The sources used were ZnSe and SnSe compounds of stoichiometric composition at the substrate temperature of 5600С. The morphological and electrophysical properties of the ZnXSn1-XSe solid solution films are investigated. Scanning electron microscope images showed that the grain sizes of the films are 8÷20 microns. The structural parameters of the obtained films are given. The electrical conductivity of the films was 15 ÷ 1 • 10-6 (Ohm·cm) -1 depending on the composition of the solid solution.
Capacitive Spectroscopy Of Defects In Semiconductors, Doped By Atoms Of Gadolinium,
2019
National University of Uzbekistan, Tashkent, Uzbekistan
Capacitive Spectroscopy Of Defects In Semiconductors, Doped By Atoms Of Gadolinium, Shoakhriyor B. Norkulov, Khodjakbar S. Daliev, Makhmud Sh. Dehkanov, Uktam K. Erugliev
Euroasian Journal of Semiconductors Science and Engineering
The processes of formation of defects in silicon, doped by gadolinium are investigated by the method of DLTS. It is shown that in diffusion the introduction of Gd in the Si leads to the formation of deep levels with ionization energies Ec–0.23 eV, Ec–0.35 eV, Ec–0.41 eV and Ec–0.54 eV and a capture cross section of electrons n: 410-17cm-2, 210-15 cm2, 1.110-16 cm2 and 1.510-15 cm2, respectively, and in samples p-Si found only one level with Ev+0.32 eV.
Features The Generalities Of I-V Curve Formation
In Mosfet With A Common Drain,
2019
Tashkent University of Information Technologies, Tashkent, Uzbekistan.
Features The Generalities Of I-V Curve Formation In Mosfet With A Common Drain, Khayrulla K. Aripov, Akhmed M. Abdullayev, Shunkurjon T. Toshmatov
Euroasian Journal of Semiconductors Science and Engineering
The results of theoretical and experimental studies of the generalities of current-voltage characteristics curve formation of metal-oxide-semiconductor transistors of the common drain are presented. The principal difference between input and output characteristics of the common drain from the analogical characteristics in the common source is shown. The source-gate and source characteristics of a metal-oxide-semiconductor transistor in the common drain are given. Combined families of source-gate and source characteristics of a metal-oxide-semiconductor transistor in the common source and drain are obtained.
Laser Testing Of Silicon Wafers,
2019
Institute of Semiconductor Physics and Microelectronics at NUUz, Tashkent, Uzbekistan
Laser Testing Of Silicon Wafers, Zakirjan T. Azamatov, Ilya A. Kulagin, Kakhkhor P. Abdurakhmanov, Nigora A. N.A. Akbarova
Euroasian Journal of Semiconductors Science and Engineering
The possibility of detection of defects in silicon wafers by Fourier analysis of digital images obtained by laser introscopy is shown.
Dc-Dc Converter For Electric Vehicle,
2019
California Polytechnic State University, San Luis Obispo
Dc-Dc Converter For Electric Vehicle, Jason Y. Zhou, Nicholas James Mah
Electrical Engineering
In this work, a DC-DC converter is designed for an electric vehicle. The DC-DC converter is designed to provide 500W with a 200-400V input and a 12-15V adjustable output. Electric vehicle sales are beginning to increase in popularity and the need for DC-DC converters to siphon power from the tractive system is not yet fully satisfied, especially for single-seater class vehicles. Additionally, improving performance in efficiency without sacrificing wide input voltage range can benefit future DC-DC converter designs. In the end, a forward active clamp DC-DC converter is designed and tested. Additionally, spreadsheet calculators, LTSpice simulations, and Matlab scripts were …
Designing A Low-Cost Ultrasound Pulser,
2019
Union College - Schenectady, NY
Designing A Low-Cost Ultrasound Pulser, Andrea Huey
Honors Theses
Ultrasound imaging allows for those studying living beings to see inside a subject without causing it harm. This allows for real-time images to be taken, leading to ease of observational research. However, while this technology is beneficial to those who utilize it, the devices used to create and receive ultrasound pulses can be incredibly complex, allowing for precise adjustment of the output signal and various other functions, and therefore expensive. The focus of this senior project is the design of a low-cost pulser for use with an ultrasound transducer. While it does not have all the high-level functions of the …
Symmetry And Dopant Diffusion In Inverted Nanopyramid Arrays For Thin Crystalline Silicon Solar Cells,
2019
University of New Mexico, Albuquerque
Symmetry And Dopant Diffusion In Inverted Nanopyramid Arrays For Thin Crystalline Silicon Solar Cells, Seok Jun Han
Chemical and Biological Engineering ETDs
In this dissertation, we enhance the efficiency of thin flexible monocrystalline silicon solar cells by breaking symmetry in light trapping nanostructures and improving homogeneity in dopant concentration profile. These thin cells are potentially less expensive than conventional thick silicon cells by using less silicon material and making the cells more convenient to be handled when supported on polymer films. Moreover, these cells are widely applicable due to their flexibility and lightweight. However, for high efficiencies, these cells require effective light trapping and charge collection. We achieve these in cells based on 14-mm-thick free-standing silicon films with light-trapping arrays of nanopyramidal …
Algorithmic Multi-Color Cmos Avalanche Photodiodes For Smart-Lighting Applications,
2019
Doctoral Student, Optical Science and Engineering
Algorithmic Multi-Color Cmos Avalanche Photodiodes For Smart-Lighting Applications, Md Mottaleb Hossain
Optical Science and Engineering ETDs
Future smart-lighting systems are expected to deliver adaptively color-tunable and high-quality lighting that is energy efficient while also offering integrated visible-light wireless communication services. To enable these systems at a commercial level, inexpensive and fast sensors with spectral-sensing capability are required. CMOS-compatible silicon avalanche photodiodes (APDs) can be an excellent fit to this problem due to their excellent sensitivity, high speeds and cost effectiveness; however, color sensing is a challenge without resorting to expensive spectral filters, as done in commercially. To address this challenge, we have recently designed and modeled a novel CMOS-compatible dual-junction APD. The device outputs two photocurrents …
Prototyping A Capacitive Sensing Device For Gesture Recognition,
2019
University of Arkansas, Fayetteville
Prototyping A Capacitive Sensing Device For Gesture Recognition, Chenglong Lin
Computer Science and Computer Engineering Undergraduate Honors Theses
Capacitive sensing is a technology that can detect proximity and touch. It can also be utilized to measure position and acceleration of gesture motions. This technology has many applications, such as replacing mechanical buttons in a gaming device interface, detecting respiration rate without direct contact with the skin, and providing gesture sensing capability for rehabilitation devices. In this thesis, an approach to prototype a capacitive gesture sensing device using the Eagle PCB design software is demonstrated. In addition, this paper tested and evaluated the resulting prototype device, validating the effectiveness of the approach.
Characterization Of High Temperature Optocoupler For Power Electronic Systems,
2019
University of Arkansas, Fayetteville
Characterization Of High Temperature Optocoupler For Power Electronic Systems, David Gonzalez
Electrical Engineering Undergraduate Honors Theses
High-temperature devices have been rapidly increas due to the implementation of new technologies like silicon carbide, high-temperature ceramic, and others. Functionality under elevated temperatures can reduce signal integrity reducing the reliability of power electronic systems. This study presents an ongoing research effort to develop a high-temperature package for optocouplers to operate at higher temperature compared with commercial devices. Low temperature co-fired ceramic (LTCC) was used as the substrate. Bare die commercial LED and photodetectors were attached to the substrate and tested for functionality. Preliminary results show enhanced performance at elevated temperatures compared to a commercial optocoupler device.
Synchrophasor-Based Fault Location Detection And Classification, In Power Systems, Using Artificial Intelligence,
2019
University of Arkansas, Fayetteville
Synchrophasor-Based Fault Location Detection And Classification, In Power Systems, Using Artificial Intelligence, Hemal Falak
Graduate Theses and Dissertations
With the introduction of sophisticated electronic gadgets which cannot sustain interruption in the provision of electricity, the need to supply uninterrupted and reliable power supply, to the consumers, has become a crucial factor in the present-day world. Therefore, it is customary to correctly identify fault locations in an electrical power network, in order to rectify faults and restore power supply in the minimum possible time. Many automated fault location detection algorithms have been proposed, however, prior art requires topological and physical information of the electrical power network. This thesis presents a new method of detecting fault locations, in transmission as …
Investigation Of Critical Technologies Of Chemical Vapor Deposition For Advanced (Si)Gesn Materials,
2019
University of Arkansas, Fayetteville
Investigation Of Critical Technologies Of Chemical Vapor Deposition For Advanced (Si)Gesn Materials, Joshua Matthew Grant
Graduate Theses and Dissertations
The development of new materials for efficient optoelectronic devices from Group IV elements is the heart of Group IV photonics. This has direct ties to modern technology as the foundation for the electronics industry is silicon. This has driven the development of silicon-based optoelectronics using these other Group IV materials as silicon is a poor optical material due to its indirect band gap when compared to the III-V semiconductors that are used by most of the optoelectronics industry. While efforts have been made to integrate III-V materials onto silicon substrates, the incompatibility with the complementary metal oxide semiconductor process has …
A Silicon Germanium Cmos Linear Voltage Regulator For Wireless Agricultural Applications,
2019
University of Arkansas, Fayetteville
A Silicon Germanium Cmos Linear Voltage Regulator For Wireless Agricultural Applications, Aminta Naidili Castillo Robles
Graduate Theses and Dissertations
This thesis presents the design, simulation and test results of a silicon germanium (SiGe) complementary metal-oxide-semiconductor (CMOS) linear regulator. The objective of the circuit is to power other analog devices regardless of the load current and input voltage changes. The application of this regulator is to be part of a project developing a miniaturized semiconductor platform that can be inserted into stems of crops in order to measure data inside the plant and then send it wirelessly to the user. The linear regulator was designed on a BiCMOS SiGe 0.13µm which is a GlobalFoundries process. It has been tested at …
