Electronic Devices and Semiconductor Manufacturing Commons^™

Five-Level Flying Capacitor Converter Used As A Static Compensator For Current Unbalances In Three-Phase Distribution Systems, Rafael Franceschi

Graduate Theses and Dissertations

This thesis presents and evaluates a solution for unbalanced current loading in three-phase distribution systems. The proposed solution uses the flying capacitor multilevel converter as its main topology for an application known as Unbalanced Current Static Compensator. The fundamental theory, controller design and prototype construction will be presented along with the experimental results. The Unbalanced Current Static Compensator main objective is the balancing of the up-stream currents from the installation point to eliminate the negative- and zero-sequence currents originated by unbalanced single-phase loads.

Three separate single-phase flying capacitor converters are controlled independently using a d-q rotating reference frame algorithm to …

Switching Trajectory Control For High Voltage Silicon Carbide Power Devices With Novel Active Gate Drivers, Shuang Zhao

Graduate Theses and Dissertations

The penetration of silicon carbide (SiC) semiconductor devices is increasing in the power industry due to their lower parasitics, higher blocking voltage, and higher thermal conductivity over their silicon (Si) counterparts. Applications of high voltage SiC power devices, generally 10 kV or higher, can significantly reduce the amount of the cascaded levels of converters in the distributed system, simplify the system by reducing the number of the semiconductor devices, and increase the system reliability.

However, the gate drivers for high voltage SiC devices are not available on the market. Also, the characteristics of the third generation 10 kV SiC MOSFETs …

Pixelated Gasb Membranes For Photovoltaics: Fabrication And Structure-Property Relationships, Vijay Saradhi Mangu

Electrical and Computer Engineering ETDs

In this thesis, I present a reliable and efficient approach to heterogeneous integration of single-crystalline GaSb semiconductors with highly mismatched materials. The mismatch may refer to the crystalline structure and the thermal expansion coefficient of single-crystalline GaSb and the other materials of interest. The strategy of hetero-integration relies on epitaxial lift-off. This approach prevents the formation of extended structural defects that are detrimental to the performance of optoelectronic devices and preserves GaSb growth substrates for potential reuse.

Within my research work, I have overcome some outstanding challenges of epitaxial lift-off of GaSb, and I have demonstrated the operation of single-crystalline …

Energy Transformation And Conservation Investigation, Mike Jackson, Holly Haney

High School Lesson Plans

Students will use a thermoelectric generator module to analyze the relationship between thermal and electrical energies. Using data collection sensors and analysis software, students will investigate the relationship between the temperature gradient across a thermoelectric generator module and the resulting electrical potential. Students will then use their data and analysis to solve problems relating to waste thermal energy in electrical systems and communicate their work to their peers and teacher.

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 …

, Abatbay K. Uteniyazov, Kanatbay A. Ismailov, Fatima T. Srajatdinova

Euroasian Journal of Semiconductors Science and Engineering

The results of studies of the direct branch of the current – voltage characteristic of the Al-Al2O3-p-CdTe-Mo structure with base thicknesses d ~ 8÷10 μm are presented. It was shown that, along with point defects and impurities, complex complexes participate in the recombination processes in the base of the structure under study. It was established that at low current densities in point of recombination processes point defects take part, and at high current densities, when the recombination rate reaches full saturation of U≈NR/τi, the recombination processes in the samples under study are determined by complex complexes within which the electrons …

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.

Optical Power Meter For Diagnostics Of Fiber-Optic Communication Lines And Digital Multimeter, Feruza A. Giyasova, B. Sh. Yuldashev, Ruslan G. Zakirov, Gulkhayo T. Murodillaeva

Euroasian Journal of Semiconductors Science and Engineering

A multifunctional optical power attenuation meter in fiber optic cables for widespread use is proposed in this article. The main feature of the proposed meter is the ability to perform of diagnostics of mechanical damage of fiber-optic communication lines and determine the attenuation degree of a signal in the fiber-optic path in the spectral ranges of 1270-1340 nm and 1520-1580 nm, as well as the measurement of voltage, current and resistance in electrical circuits. The possibility of using the meter for diagnostics of onboard fiber-optic communication lines is justified.

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.

The Principles Of Increasing The Sensitivity Of Transistor Structures To External Influences, Davron R. Djuraev, Abdulaziz V. Karimov, Dilbara M. Yodgorova, Akmal A. Turaev

Euroasian Journal of Semiconductors Science and Engineering

This article discusses a multifunctional sensor based on a field-effect transistor with a p-n-junction. The sensor allows to register temperature, light intensity, pressure with high level of sensitivity. At the same time, ensuring the sensitivity of the structure to external influences is practically solved due to constructive changes. Due to constructive solutions, the proposed sensor based on a field-effect transistor greatly exceeds the similar diode structures in sensitivity.

Influence Of Heat Treatment On The Behaviorof 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, 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.

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.

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.

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.

Organic Photodiodes On The Basis Of Cottonfiber/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 …

Influence Of Impurities Of Refractory Elements On The Inefficiency Of Charge Transfer In Charged Communication Devices, Abdugafur T. Mamadalimov, Shakhrukh Kh. Daliev

Euroasian Journal of Semiconductors Science and Engineering

The influence of impurities of refractory elements on the inefficiency of charge transfer in charge-coupled devices is investigated. Found that the magnitude of the inefficiency of transfer  directly proportional to the density of surface States and the density of surface States in the CCD registers, with the resulting n losses n ≤ 0.1 depends on the type specially introduced impurities. It is shown that in CCD structures doped with impurities Ti, Zr and Hf relative to the control structures, the charge loss is greater, and in doped with impurities W and Mo, the charge loss is less.

Influence Of Rhodium And Iridium Impurity Atoms On The Capacitive Characteristics Of Si-Siо2 Structures, Khojakbar S. Daliev, Shakhriyor Kh. Yulchiev, Xotamjon J. Mansurov

Euroasian Journal of Semiconductors Science and Engineering

It was found that the doping of the semiconductor substrate with Rh and Ir atoms leads to the increase in the density of surface states at the Si – SiO2 interface. It is determined that the surface states, due to the presence of an impurity Rh and Ir are effective generation centers.

The Influence Of Γ -Irradiation On The Holographic Characteristics Of Chalcogenide Glassy Semiconductor, Zakirjan T. Аzamatov, Mira R. Bekchanova, Timur Z. Azamatov

Euroasian Journal of Semiconductors Science and Engineering

Results of the research of holographic characteristics of chalcogenide glassy semiconductor films, under the influence of irradiation are presented. Found that in the range of radiation doses (roentgen) optical properties of (CGS) films and diffraction efficiency recorded holograms does not change. Also proved that the shelf life recorded holograms under certain conditions is 10 years or more.

Volt-Ampere Characteristics Of Mos Structures Al-Al2o3-P-Cdte-Mo – In The Forward Direction Of Current, Abatbay K. Uteniyazov, Kanatbay A. Ismailov, Fatima T. Srajatdinova

Euroasian Journal of Semiconductors Science and Engineering

The results of studies of the direct branch of the current – voltage characteristic of the Al-Al2O3-p-CdTe-Mo structure with base thicknesses d ~ 8÷10 μm are presented. It was shown that, along with point defects and impurities, complex complexes participate in the recombination processes in the base of the structure under study. It was established that at low current densities in point of recombination processes point defects take part, and at high current densities, when the recombination rate reaches full saturation of U≈NR/τi, the recombination processes in the samples under study are determined by complex complexes within which the electrons …