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Загальна кількість знайдених документів : 25
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1.

Klad'ko V. P. 
X-ray diffraction study of deformation state in InGaN/GaN multilayered structures [Електронний ресурс] / V. P. Klad'ko, A. V. Kuchuk, N. V. Safryuk, V. F. Machulin, A. E. Belyaev, R. V. Konakova, B. sS. Yavich // Semiconductor physics, quantum electronics & optoelectronics. - 2010. - Vol. 13, № 1. - С. 1-7. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2010_13_1_3
Попередній перегляд:   Завантажити - 713.906 Kb    Зміст випуску     Цитування
2.

Belyaev A. E. 
The features of temperature dependence of contact resistivity of Au Ti Pd2Si p+-Si ohmic contacts [Електронний ресурс] / A. E. Belyaev, N. S. Boltovets, L. M. Kapitanchuk, R. V. Konakova, V. P. Kladko, Ya. Ya. Kudryk, A. V. Kuchuk, O. S. Lytvyn, V. V. Milenin, T. V., Ataubaeva A. B., Nevolin P. V. Korostinskaya // Semiconductor physics, quantum electronics & optoelectronics. - 2010. - Vol. 13, № 1. - С. 8-11. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2010_13_1_4
We consider the features of formation of Au - Ti - Pd ohmic contacts to <$E p sup +>-S. Metallization was made by vacuum thermal sputtering of Pd, Ti and Au films onto the Si substrate heated up to 330 <$E symbol Р>C. It is shown that the contact resistivity increases wil temperature; this is typical of metallic conductivity. We suggest that the ohmic contact formed owing to appearance of shunts at Pd deposition on dislocations or other structural defects. The number of shunts per unit area is close to the measured density of structural defects at the metal - Si interface.
Попередній перегляд:   Завантажити - 527.135 Kb    Зміст випуску    Реферативна БД     Цитування
3.

Boltovets M. S. 
Formation of ohmic contacts to n(p)-gan and measurement of their contact resistivity [Електронний ресурс] / M. S. Boltovets, V. M. Ivanov, R. V. Konakova, Ya. Ya. Kudryk, V. V. Milenin, V. V. Shynkarenko, V. M. Sheremet, Yu. N. Sveshnikov, B. S. Yavich // Semiconductor physics, quantum electronics & optoelectronics. - 2010. - Vol. 13, № 4. - С. 337-342. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2010_13_4_3
We propose multilayer ohmic contacts to n- and p-GaN layers, with titanium boride as diffusion barrier. It is shown that the optimal method of contact resistivity measurement is the transmission line method (TLM) with circular contact geometry. The Ti - Al - TiBx - Au contact metallization to n-GaN retains its layer structure after thermal annealing at temperatures up to 900 <$E symbol Р>C. The contact resistivity <$E rho sub c> is <$E ( 6,69~symbol С~1,67 )~times~10 sup -5~OMEGA~cdot~roman cm sup 2>. For the Au - TiBx - Ni - p-GaN contact structure, the contact resistivity is <$E (1~symbol С~0,15)~cdot~10 sup -3~OMEGA~cdot~roman cm sup 2>.
Попередній перегляд:   Завантажити - 261.658 Kb    Зміст випуску    Реферативна БД     Цитування
4.

Belyaev A. E. 
Temperature dependence of contact resistance of Au Ti Pd2Si n+-Si ohmic contacts [Електронний ресурс] / A. E. Belyaev, N. S. Boltovets, R. V. Konakova, Ya. Ya. Kudryk, A. V. Sachenko, V. N. Sheremet // Semiconductor physics, quantum electronics & optoelectronics. - 2010. - Vol. 13, № 4. - С. 436-438. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2010_13_4_24
We investigated temperature dependence of contact resistance of an Au - Ti - Pd2Si ohmic contact to heavily doped <$E n sup + - roman Si>. The contact resistance increases with temperature owing to conduction through the metal shunts. In this case, the limiting process is diffusion input of electrons to the metal shunts. The proposed mechanism of contact resistance formation seems to realize also in the case of wide-gap semiconductors with high concentration of surface states and dislocation density in the contact.
Попередній перегляд:   Завантажити - 143.056 Kb    Зміст випуску    Реферативна БД     Цитування
5.

Belyaev A. E. 
Some aspects of thermal resistance measurement technique for IMPATT and light-emitting diodes [Електронний ресурс] / A. E. Belyaev, N. S. Boltovets, R. V. Konakova, Ya. Ya. Kudryk, V. M. Sorokin, V. N. Sheremet, V. V. Shynkarenko // Semiconductor physics, quantum electronics & optoelectronics. - 2011. - Vol. 14, № 4. - С. 465-469. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2011_14_4_19
Some aspects of measuring the thermal resistance to a constant heat flow at a p-n junction - package region in IMPATT and light-emitting diodes are considered. We propose a method of studying the thermal resistance of high-power light-emitting diodes. This method makes it possible to increase accuracy of measuring the thermal resistance by determining the temperature at a linear section of the voltage - temperature curve. A possibility to measure the thermal resistance of IMPATT diodes by using the pulse I-V curves is shown. This enables one to simplify calculations and increase accuracy of measuring the thermal resistance.
Попередній перегляд:   Завантажити - 380.441 Kb    Зміст випуску    Реферативна БД     Цитування
6.

Sorokin V. M. 
Technique and setup for diagnostics of p-n junction to case thermal resistance in high-power gallium nitride LEDs [Електронний ресурс] / V. M. Sorokin, R. V. Konakova, Ya. Ya. Kudryk, A. V. Zinovchuk, R. I. Bigun, R. Ya. Kudryk, V. V. Shynkarenko // Semiconductor physics, quantum electronics & optoelectronics. - 2012. - Vol. 15, № 2. - С. 124-128. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2012_15_2_5
We present a setup and procedure of studying p - n junction to case thermal resistance in high-power light-emitting diodes (LEDs) from their thermal relaxation. A set of LEDs mounted on a metal-core printed circuit board (MCPCB) were studied. The contributions to the total thermal resistance from a heavy heat sink, MCPCB, heat slug and LED chip are separated.
Попередній перегляд:   Завантажити - 2.448 Mb    Зміст випуску    Реферативна БД     Цитування
7.

Bacherikov Yu. Yu. 
Interface features of SiO2/SiC heterostructures according to methods for producing the SiO2 thin films [Електронний ресурс] / Yu. Yu. Bacherikov, N. S. Boltovets, R. V. Konakova, E. Yu. Kolyadina, T. M. Ledn'ova, O. B. Okhrimenko // Semiconductor physics, quantum electronics & optoelectronics. - 2012. - Vol. 15, № 1. - С. 13-16. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2012_15_1_5
Попередній перегляд:   Завантажити - 188.577 Kb    Зміст випуску     Цитування
8.

Sachenko A. V. 
Resistance formation mechanisms for contacts and to n-AlN and n-GaN with a high dislocation density [Електронний ресурс] / A. V. Sachenko, A. E. Belyaev, N. S. Boltovets, Yu. V. Zhilyaev, L. M. Kapitanchuk, V. P. Klad'ko, R. V. Konakova, Ya. Ya. Kudryk, A. V. Kuchuk, A. V., Panteleev V. V., Sheremet V. N. Naumov // Semiconductor physics, quantum electronics & optoelectronics. - 2012. - Vol. 15, № 4. - С. 351-357. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2012_15_4_11
We studied temperature dependences of the resistivity, <$E rho sub c (T)>, of Pd-Ti-Pd-Au ohmic contacts to wide-gap semiconductors n-GaN and n-AlN with a high dislocation density. Both <$E rho sub c (T)> curves have portions of exponential decrease, as well as those with very slight <$E rho sub c (T)> dependence at higher temperatures. Besides, the Au-Pd-Ti-Pd-n-GaN contacts have a portion of <$E rho sub c (T)> flattening out in the low-temperature region. This portion appears only after rapid thermal annealing (RTA). In principle, its appearance may be caused by preliminary heavy doping of the near-contact region with a shallow donor impurity as well as doping in the course of contact formation owing to RTA, if the contact-forming layer involves a material atoms of which serve as shallow donors in III - N compounds. The obtained <$E rho sub c (T)> dependences cannot be explained by the existing mechanisms of current transfer. We propose other mechanisms explaining the experimental <$E rho sub c (T)> curves for ohmic contacts to n-GaN and n-AlN.
Попередній перегляд:   Завантажити - 2.659 Mb    Зміст випуску    Реферативна БД     Цитування
9.

Belyaev A. E. 
Role of dislocations in formation of ohmic contacts to heavily doped n-Si [Електронний ресурс] / A. E. Belyaev, V. A. Pilipenko, V. M. Anischik, T. V. Petlitskaya, A. V. Sachenko, V. P. Klad'ko, R. V. Konakova, N. S. Boltovets, T. V. Korostinskaya, L. M. Kapitanchuk // Semiconductor physics, quantum electronics & optoelectronics. - 2013. - Vol. 16, № 2. - С. 99-110. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2013_16_2_3
We present experimental results concerning a high density of structural defects (in particular, dislocations) in the near-contact region of heavily doped n-silicon. They appear in the course of firing Au - Pd - Ti - Pd - <$En sup +> - Si ohmic contact at <$E450~symbol Р roman C> for 10 min in a vacuum of ~ 10<^>-4 Pa. These defects lead to appearance of metal shunts that determine the current flow mechanism in these ohmic contacts. The calculated and experimental temperature dependences of contact resistivity, <$Erho sub c (T)>, are in good agreement. It is shown that <$Erho sub c> increases with temperature. This is characteristic of a model of ohmic contacts with a high dislocation density in the near-contact region of semiconductor.
Попередній перегляд:   Завантажити - 4.777 Mb    Зміст випуску    Реферативна БД     Цитування
10.

Belyaev A. E. 
Effect of microwave radiation on I V curves and contact resistivity of ohmic contacts to n-GaN and n-AlN [Електронний ресурс] / A. E. Belyaev, N. S. Boltovets, Yu. V. Zhilyaev, V. S. Zhigunov, R. V. Konakova, V. N. Panteleev, A. V. Sachenko, V. N. Sheremet // Semiconductor physics, quantum electronics & optoelectronics. - 2013. - Vol. 16, № 3. - С. 289-292. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2013_16_3_12
Попередній перегляд:   Завантажити - 1.328 Mb    Зміст випуску     Цитування
11.

Sachenko A. V. 
Mechanism of current flow and temperature dependence of contact resistivity in Au-Pd-Ti-Pd-n+-GaN ohmic contacts [Електронний ресурс] / A. V. Sachenko, A. E. Belyaev, N. S. Boltovets, L. M. Kapitanchuk, V. P. Klad'ko, R. V. Konakova, A. V. Kuchuk, T. V. Korostinskaya, A. S. Pilipchuk, V. N., Mazur Yu. I., Ware M. E., Salamo G. J. Sheremet // Semiconductor physics, quantum electronics & optoelectronics. - 2013. - Vol. 16, № 4. - С. 313-321. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2013_16_4_3
We present the results of structural and morphological investigations of interactions between phases in the layers of Au-Pd-Ti-Pd-n<^>+-GaN contact metallization that appear at rapid thermal annealing (RTA). It is shown that formation of ohmic contact occurs in the course of RTA at <$E T~=~900~symbol Р roman C> due to formation of titanium nitride. We studied experimentally and explained theoretically the temperature dependence of contact resistivity <$E rho sub c (T)> of ohmic contacts in the 4,2 - 380 K temperature range. The <$E rho sub c (T)> curve was shown to flatten out in the 4,2 - 50 K range. As temperature grew, <$E rho sub c> decreased exponentially. The results obtained enabled us to conclude that current flow has field nature at saturation of <$E rho sub c (T)> and the thermofield nature in the exponential part of <$E rho sub c (T)> curve.
Попередній перегляд:   Завантажити - 900.744 Kb    Зміст випуску    Реферативна БД     Цитування
12.

Sachenko A. V. 
On a feature of temperature dependence of contact resistivity for ohmic contacts to n-Si with an n+-n doping step [Електронний ресурс] / A. V. Sachenko, A. E. Belyaev, N. S. Boltovets, A. O. Vinogradov, V. A. Pilipenko, T. V. Petlitskaya, V. M. Anischik, R. V. Konakova, T. V. Korostinskaya, V. P., Kudryk Ya. Ya., Lyapin V. G., Romanets P. N., Sheremet V. N. Kostylyov // Semiconductor physics, quantum electronics & optoelectronics. - 2014. - Vol. 17, № 1. - С. 1-6. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2014_17_1_3
We present both theoretical and experimental temperature dependences of contact resistivity <$E rho sub c (T)> for ohmic contacts to the silicon <$E n sup + -n>-structures whose <$E n sup +>-layer was formed using phosphorus diffusion or ion implantation. The <$E rho sub c (T)> dependence was measured in the 125 - 375 K temperature range with the transmission line method, with allowance made for conduction in both the <$E n sup +>-layer and <$E n sup + -n> doping step.
Попередній перегляд:   Завантажити - 668.622 Kb    Зміст випуску    Реферативна БД     Цитування
13.

Konakova R. V. 
Effect of weak magnetic fields treatment on photoluminescence of III-V single crystals [Електронний ресурс] / R. V. Konakova, S. M. Red'ko, V. V. Milenin, R. A. Red'ko // Semiconductor physics, quantum electronics & optoelectronics. - 2014. - Vol. 17, № 1. - С. 75-79. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2014_17_1_16
The long-term transformations of photoluminescence of GaP, GaAs and InP single crystals treated with pulsed weak magnetic fields are obtained. The treatments were performed in two regimes, namely, single-pulse (<$E tau> = 30 ms) and multi-pulse (<$E tau> = 1,2 ms) ones, at varying magnitudes of magnetic induction. The defect structure transformations were inferred from the radiative recombination spectra in the 0,6 - 2,5 <$E mu>m at 77 K. A possible mechanism of observed modifications related to the electron spin transformation is discussed.
Попередній перегляд:   Завантажити - 1.535 Mb    Зміст випуску    Реферативна БД     Цитування
14.

Konakova R. V. 
Influence of pulse magnetic fields treatment on optical properties of GaAs based films [Електронний ресурс] / R. V. Konakova, M. V. Sosnova, S. M. Red'ko, V. V. Milenin, R. A. Red'ko // Semiconductor physics, quantum electronics & optoelectronics. - 2014. - Vol. 17, № 2. - С. 130-133. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2014_17_2_4
Long-term transformations of the optical reflectance of GaAs epitaxial structure under weak magnetic field treatment (B = 60 mT, f = 10 Hz, <$E tau> = 1,2 ms, t = 5 min) have been obtained. Optical measurements were performed within the wavelength range 800 - 1100 nm at 300 K. Non-monotonous changes of reflectance were observed. Experimental results have been interpreted in terms of diffusion of point defects, resulting from destruction of metastable complexes (probably [VAs + impurity]), from the internal boundaries to the surfaces of the investigated structures. The method for detection of non-equilibrium complexes in multilayer objects has been proposed.
Попередній перегляд:   Завантажити - 1.759 Mb    Зміст випуску    Реферативна БД     Цитування
15.

Belyaev A. E. 
Optical properties of irradiated epitaxial GaN films [Електронний ресурс] / A. E. Belyaev, N. I. Klyui, R. V. Konakova, A. M. Luk’yanov, Yu. M. Sveshnikov, A. M. Klyui // Ukrainian journal of physics. - 2014. - Vol. 59, № 1. - С. 34-37. - Режим доступу: http://nbuv.gov.ua/UJRN/Ukjourph_2014_59_1_6
Попередній перегляд:   Завантажити - 301.587 Kb    Зміст випуску     Цитування
16.

Belyaev A. E. 
Ohmic contacts based on Pd to indium phosphide Gunn diodes [Електронний ресурс] / A. E. Belyaev, N. S. Boltovets, A. V. Bobyl, A. V. Zorenko, I. N. Arsentiev, V. P. Kladko, V. M. Kovtonyuk, R. V. Konakova, Ya. Ya. Kudryk, A. V. Sachenko // Semiconductor physics quantum electronics & optoelectronics. - 2015. - Vol. 18, № 3. - С. 317-323. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2015_18_3_16
Experimental data on manufacturing the ohmic contacts Au - Ti - Pd - n+ - InP, formed using vacuum deposition of metal onto a heated to <$E300~symbol Р roman C> substrate representing an epitaxial n<^>+-n-n<^>++-n<^>+++-InP structure. The specific contact resistance measured at room temperature was about <$E7~cdot~10 sup -5 ~roman {Ohm~cdot~cm sup 2 }>. Voltage-current characteristics within the temperature range 110 to 380 K are linear. Gunn diodes with such contacts, which were made as a straight mesa-structure in a pulsed mode (pulse duration of 100 ns, pulse ratio of 1000, operating current of 2,2 A), generated the microwave power ~ 10 mW in the V-band.
Попередній перегляд:   Завантажити - 315.782 Kb    Зміст випуску    Реферативна БД     Цитування
17.

Belyaev A. E. 
Structural and electrical-physical properties of the ohmic contacts based on palladium to n+-n-n++-n+++-InP [Електронний ресурс] / A. E. Belyaev, N. A. Boltovets, A. B. Bobyl, V. P. Kladko, R. V. Konakova, Ya. Ya. Kudryk, M. U. Nasyrov, A. V. Sachenko, V. S. Slipokurov, A. S. Slepova // Semiconductor physics, quantum electronics & optoelectronics. - 2015. - Vol. 18, № 4. - С. 391-395. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2015_18_4_5
Presented in this paper are experimental data on structural properties of contact metallization and temperature dependence of the specific contact resistance for ohmic contacts Au - Ti - Pd -n<^>+- InP and Au - Ti - Ge - Pd -n<^>+- InP prepared using the method of successive thermal evaporation of metals in oil-free vacuum in one process cycle onto the n<^>+-n-n<^>++-n<^>+++-InP epitaxial structure heated to <$E300~symbol Р roman C>. It has been theoretically and experimentally shown that within the temperature range 250 - 380 K the current transport mechanism in the ohmic contacts Au - Ti - Pd -n<^>+- InP is thermal-field one, and in the ohmic contacts Au - Ti - Ge - Pd -n<^>+-InP it is caused by conductivity along metal shunts linked with dislocations. According to the X-ray diffraction data, the density of these dislocations in the near-contact InP area is ~10<^>9 cm<^>-2.
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18.

Romanets P. M. 
Theoretical and experimental modelling the specific resistance of vertical ohmic contacts Au–Ti–Pd–n+-n-n+-Si in IMPATT diodes [Електронний ресурс] / P. M. Romanets, A. E. Belyaev, А. V. Sachenko, N. S. Boltovets, V. V. Basanets, R. V. Konakova, V. S. Slipokurov, А. А. Khodin, V. А. Pilipenko, V. V. Shynkarenko // Semiconductor physics, quantum electronics & optoelectronics. - 2016. - Vol. 19, № 4. - С. 366-370. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2016_19_4_9
The method of electrophysical diagnostic of n+ - n - n+ structures at the etching stage of manufacturing process of power IMPATT diodes has been proposed. A numerical method for specific contacts resistance calculation of vertical ohmic contacts with a non-uniform doping level has been developed. Vertical ohmic contacts Au - Ti - Pd - n+ - n - n+ - Si both before and after etching were used for experimental checking this model. It has been computed the value of contact resistance in the interface metal-n+ with correction of contribution of n+ - n and n - n+ resistances to the total resistance. The values of total effective resistances of vertical ohmic contacts Au - Ti - Pd - n+ - n - n+ - Si may be calculated using the Cox-Strack method. We used solutions of Laplace's equation for computation of specific contact resistance metal-n+ without contribution of interfaces n+ - n and n - n+. The values of specific contact resistance were ~10-6 Ohm · cm2. This method allows to control the manufacture process by monitoring the changes in electrophysical properties of the structure between etching cycles.
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19.

Vakhnyak N. D. 
Transformation of impurity-defect centers in single crystals CdTe: Cl under the influence of microwaves [Електронний ресурс] / N. D. Vakhnyak, O. P. Lotsko, S. I. Budzulyak, L. A. Demchyna, D. V. Korbutyak, R. V. Konakova, R. A. Red’ko, O. B. Okhrimenko, N. I. Berezovska // Semiconductor physics, quantum electronics & optoelectronics. - 2017. - Vol. 20, № 2. - С. 250-253. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2017_20_2_20
Performed in this work are the researches of the influence of microwave irradiation (2,45 GHz, 24 GHz) on spectra of low-temperature (T = 2 K) photoluminescence (PL) in single crystals CdTe:Cl. Transformation of impurity-defect centers in CdTe:Cl responsible for PL within the spectral range 1,3 to 1,5 eV under microwave irradiation was analyzed. The parameter of electron-phonon interaction (Huang-Rhys factor) for the donor-acceptor PL band, which depends on the time of microwave irradiation, has been calculated.
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20.

Bacherikov Yu. Yu. 
Optical properties of thin erbium oxide films formed by rapid thermal annealing on SiC substrates with different structures [Електронний ресурс] / Yu. Yu. Bacherikov, R. V. Konakova, O. B. Okhrimenko, N. I. Berezovska, L. M. Kapitanchuk, A. M. Svetlichnyi // Semiconductor physics, quantum electronics & optoelectronics. - 2017. - Vol. 20, № 4. - С. 465-469. - Режим доступу: http://nbuv.gov.ua/UJRN/MSMW_2017_20_4_13
The comparative analysis of optical characteristics inherent to Er2O3/SiC and Er2O3/por-SiC/SiC structures has been performed. It has been shown that, regardless the substrate on which the Er2O3 film is formed, an increase in the rapid thermal annealing time leads to an improvement in the oxide film composition, with the composition of the Er2O3 film approaching to the stoichiometric one. At the same time, introduction of an additional porous SiC layer leads to a blurring of the oxide film/substrate interface and broadening the photoluminescence band measured in this structure.
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