Kozlov Vladimir

PK "FID-Tekhnika (basic employment)& Ioffe Physical Technical Institute (part-time worker) · R&D department (PK "FID-Tekhnika)& Cyclotron Lab (Ioffe Institute)

Using the deep-level transient spectroscopy and reverse recovery method, the minority carrier lifetime in the base n0-layers of high-voltage GaAs p+–p0–i–n0–n+-diodes grown by the liquid phase epitaxy in argon atmosphere has been estimated before and after irradiation by neutrons with the energy of 1 MeV and the fluence of 1.6 × 1014 cm–2. Correlat...

The mechanical strength of various silicon wafers with a thickness of 100 µm has been studied, depending on the methods of their preparation and the modes of their subsequent grinding or polishing, including chemical-mechanical (HMP). The plates were loaded using the ring-to-ring method, the magnitude of stresses and deflection under the small ring...

The mechanical strength of various silicon wafers with a thickness of 100 μm has been studied, depending on the methods of their preparation and the modes of their subsequent grinding or polishing, including chemical-mechanical (HMP). The plates were loaded using the ring-to-ring method, the magnitude of stresses and deflection under the small ring...

The mechanical strength of silicon wafers of 100 µm thickness was studied. Loading of the wafers was carried out by the “ring-on ring” method, stress and deflection under the small ring were determined by finite element modeling. The validity of the calculation model was checked by comparing the dependences of the deflection under the small ring on...

The mechanical strength of silicon wafers of 100 μm thickness was studied. Loading of the wafers was carried out by the "ring-on ring" method, stress and deflection under the small ring were determined by finite element modeling. The validity of the calculation model was checked by comparing the dependences of the deflection under the small ring on...

The paper presents an overview of the current state of the art for Russian power electronics in terms of the semiconductor materials, technologies and component base used. An analysis has been made of the existing problems and successes for this feld of electronics and its prospects for development as well.

The work considers the design and parameters of the installation for assembly of semiconductor chips on contact sites using the method of low-temperature silver nanoparticle sintering.

The mechanical strength of ultra-thin 100 μm Si wafers was measured depending on Si growing methods and machining modes of wafer surface preparation (abrasive grinding, diamond paste polishing, chemical-mechanical polishing — CMP).

The mechanical strength of ultra-thin 100 μm Si wafers was measured depending on Si growing methods and machining modes of wafer surface preparation (abrasive grinding, diamond paste polishing, chemical-mechanical polishing — CMP)

В работе рассмотрены возможности технологии модифицирования полупроводников (Si, GaAs, SiC) и коррекции характеристик полупроводниковых приборов с использованием методов имплантации ионов высоких энергий. Обсуждаются особенности построения технологической линейки и оборудования для выполнения процессов обработки пластин большого диаметра на базе ци...

The main possible application of the technology for semiconductor material modification and correction of semiconductor device characteristics via high energy ion implantation are considered in the paper. Features of the technological line and equipment for treatment of large diameter wafers are discussed on example of the Ioffe Institute cyclotron...

В работе рассмотрены возможности технологии модифицирования полупроводников ( Si, GaAs, SiC ) и коррекции характеристик полупроводниковых приборов с использованием методов имплантации ионов высоких энергий. Обсуждаются особенности построения технологической линейки и оборудования для выполнения процессов обработки пластин большого диаметра на базе...

The presentation is about the technolgical possibilities of ”North-West Radiation Technological Center” in the field of Semiconductor Material and Device Modification by Irradiation with Ion Beams

The paper considers the main features of liquid-phase epitaxy method for high-voltage heterostructure growth on the base of GaAs solid solutions considered, as well as some examples of power and pulse power devices with subnanosecond switching speed and with switching frequency of 10MHz and above.

GaAs is a semiconductor with very high electron mobility, relatively large breakdown field and forbidden band gap compared to Si and with low carrier lifetime as well due to direct zone structure. Additionally, GaAs is a high quality and low cost material, compared to SiC and GaN, which can apply for the leading position among semiconductors for hi...

Nowadays, ion implantation of semiconductors with light ions (proton and alpha-particles) became a very popular tool for correction of the power diode characteristics [1]. This technology allows optimization of trade-off between dynamic and static parameters of power diodes due to controllable formation of radiation defects in local layers of the d...

Silicon based multilayered epitaxial structures are currently the main material for large-scale commercial fabrication of generally used power semiconductor devices such as fast recovery epitaxial diodes (FRED), isolate gate bipolar transistor (IGBT), power MOSFETs etc. Defects in silicon based multilayer epitaxial structures used as the initial ma...

An experimental study of the capacitance–voltage (C–V) characteristics and deep-level transient spectroscopy (DLTS) of p +–p 0–i–n 0 structures based on undoped GaAs, grown by liquid-phase epitaxy at two crystallization-onset temperatures T o (950 and 850°C), with optical illumination switched off and on, are performed. It is shown that the p 0, i,...

The possibility of improving the dynamic characteristics of turn-off switching of high-voltage power GaAs p-i-n diode by applying a heteroepitaxial AlGaAs emitter is investigated in this work. Using a wideband AlGaAs n⁺-emitter in manufacturing of power GaAs p-i-n diodes allows to vary the coefficient K value which characterizes the recovery softne...

Physical basis of using the controlled defect formation in InGaAs heteroepitaxial layers to vary the carrier lifetime is considered. It is shown that the lifetime of nonequilibrium carriers in the base layers of a diode can be controllably varied from several to hundreds of nanoseconds. The results obtained in a study of (i) structural defects and...

Рассмотрены основные аспекты влияния протонного облучения на скорость восстановления блокирующей способности и мягкость переключения силовых GaAs-A3 B5 p- i-n диодов, а также на их вольт-амперные характеристики. Приведены характеристики переключения сверх-быстродействующих силовых высокочастотных гетероэпитаксиальных p-i-n диодов.

Processes of heat transfer through interfaces of semiconductor diode stack structures of high voltage pulse switchers are investigated by laser thermal wave methods. Theoretical model of thermal wave propagation in such structures is developed. It takes into account specific features of preparation of semiconductor element surfaces, layers of solde...

The defects in silicon based multilayer epitaxial structures intended for power epitaxial-diffusion devices as initial material were studied by x -ray topography techniques. It was shown the dislocation nets with non-uniform distribution of dislocations both over thickness and layer square in the form of dense rows (dislocation walls) or slip bands...

X-ray topography and high-resolution diffractometry methods are used for testing GaAs wafers from different manufacturers, which are used as substrates for epitaxial growth in construction of power semi-conductor devices. Typical features of such wafers are a distorted surface layer, bent, and growth dislocations with two types of distribution with...

Рассмотрены физические основы техники контролируемого дефектообразования на гетерограницах и в объеме эпитаксиальных GaAs слоев при их изовалентном легировании. Приводятся результаты исследования собственных дефектов и их перестройки в зависимости от режимов изовалентного легирования при эпитаксиальном росте. Рассмотрены основные аспекты влияния де...

The paper considers the physical basis for the technique of controllable defect formation at heterointerfaces and in the bulk of epitaxial GaAs layers in the process of isovalent doping. Results of studying crystal defects and their rearrangement depending on the isovalent doping modes in the process of epitaxial growth are presented. The main aspe...

Laser TW methods provide important information about dynamic heat-exchange properties of the bonded wafer interfaces in multielement semiconductor devices fabricated using various assembly technologies at the micro-scale level. They can be used for diagnostics of the heat transfer quality in soldered contacts and their degradation in semiconductor...

Heat transferring through the interfaces of diode structures assembled by various techniques in high voltage stacks and from multijunction solar cells to the ceramic baseplate are investigated by laser thermal wave methods. A theoretical model of thermal wave propagation in such structures is developed. It takes into account specific features of se...

Processes of heat transfer through interfaces of semiconductor diode stack structures of high voltage pulse switchers are investigated by laser thermal wave methods. Theoretical model of thermal wave propagation in such structures is developed. It takes into account specific features of preparation of semiconductor element surfaces, layers of solde...

Laser thermowave photodeflection methods have been used to study the process of heat transfer in bonded interfaces of semiconductor diode structures of high-voltage opening switches fabricated according to the stack technology. A theoretical model is proposed for the description of thermal wave propagation in these structures with allowance for tec...

The study is concerned with the effect of short-term high-temperature heating on Si:Se and Si:S samples, whose surface layers are doped with phosphorus to high concentrations. It is found that the resistivity of the wafers substantially increases deep in the bulk within up to ∼10 μm. The experimental data suggest that this effect is due to enhanced...

It is shown experimentally for the first time that the operation of GaAs drift step-recovery diodes produced on the basis of p +-p 0-n 0-n + is accompanied by the generation of ultrahigh-frequency oscillations in the form of trains of short pulses with a duration of ∼10 ps. The amplitude and repetition frequency of these pulses are as high as ∼100...

Experimental results of studying the dynamics of recovery of diodes based on lightly doped epitaxial layers of gallium arsenide are reported. The diodes under consideration belong to the class of drift diodes with step recovery and are designed to operate in circuits for shaping and generating picosecond pulses. The obtained values of the reverse-...

The advance in the achievement of semiconductors DSRD enables to a wide range of nano-and subnanosecond pulse generators development. One should mentioned, that special efforts need to realize such advantages of DSRD as low jitter, high efficiency, high repetition rate. There are several generators circuits had been developed for different classes...

A new generation of drift step recovery diodes (DSRD) has been developed and demonstrated. Switching time of the DSRDs was reduced down to the 100 ps level, while average pulse repetition rate increased up to 10 MHz with time stability of switching as low as 10 ps. Fast, stable and high-frequency operation of silicon DSRDs makes them suitable for t...

UHF IMPATT oscillations followed (under certain conditions) by a reversible impact ionization wave breakdown and picosecond pulse generation at up to 50GHz frequencies have been for the first time experimentally observed in GaAs DSRDs. A possible physical model and practical implementation of the phenomenon observed are discussed for ultra wideband...

Experimental results of studying recovery dynamics of GaAs diodes based on weakly-doped layers grown by liquid-phase epitaxy are presented. The diodes belong to a class of drift step recovery diodes (DSRDs) and are intended for operation in circuits generating high-power picosecond pulses. The obtained values of recovery rates for the reverse volta...

Electrostatic force microscopy was used to study the potential distribution in a forward-biased epitaxial-diffused n +-n-p-p + silicon diode. Distributions of potential and capacitance were determined across the cleaved surface, which intersected the layers in the diode structure. Variations in the surface potential and capacitance were preliminari...

Проведено исследование скрытых наноразмерных дефектных слоев, сформированных в кристаллах Si и SiC имплантацией водорода с энергией 50 и 100 кэВ. Показана высокая чувствительность использованного метода атомно-силовой микроскопии для обнаружения начальных стадий развития водородсодержащих пор и микротрещин в подповерхностных слоях облученных криста...

Electrostatic force microscopy was used to study the potential distribution in a forward-biased epitaxial–diffused n+–n–p–p+ silicon diode. Distributions of potential and capacitance were determined across the cleaved surface, which intersected the layers in the diode structure. Variations in the surface potential and capacitance were preliminarily...

Buried nanoscale damaged layers formed in Si and SiC crystals via 50-and 100-keV proton implantation were studied. It is shown that the sensitivity of atomic-force microscopy is sufficiently high to detect the initial stages of the development of hydrogen-containing voids and microcracks in subsurface layers of irradiated crystals and to study exfo...

The paper describes the features of construction and production technology of new silicon DSRD-generation for operation in high frequency circuits (10³-10⁷ Hz) with subnanosecond switching time (0.1-0.5 ns) and very low jitter (∼10 ps). The main purpose of this work is to scale physical phenomena in traditional thick DSRD-stru...

One of the modern methods for modifying semiconductors using beams of protons and alpha particles is analyzed; this modification is accomplished by the controlled introduction of radiation defects into the semiconductor. It is shown that doping semiconductors with radiation defects produced by irradiation with light ions opens up fresh opportunitie...

One of the modern methods for modifying semiconductors using beams of protons and alpha particles is analyzed; this modification is accomplished by the controlled introduction of radiation defects into the semiconductor. It is shown that doping semiconductors with radiation defects produced by irradiation with light ions opens up fresh opportunitie...

High frequency IMPATT oscillations followed under certain conditions by reversible impact ionization wave breakdown of the p +-n-n + diode structure have been experimentally observed for the first time in a drift step recovery diode operating in the avalanche breakdown mode after a fast voltage restoration of the p-n junction.

The method of secondary-ion mass-spectrometry has been applied to investigate the hydrogen distribution in Si and SiC after high-temperature proton irradiation (Tirr = 20-700°C). It has been shown that hydrogen concentration profiles in SiC do not depend on the irradiation temperature. A change of the profile is observed in Si at Tirr ∼ 300°C. The...

Analysis is given of the progress in the modification of semiconductors by proton beams in fields such as proton-enhanced diffusion, ion-beam mixing, and formation of porous layers. This method of modification (doping) is shown to have high potential in monitoring the properties of semiconductor materials and designing devices of micro and nano ele...

Analysis is given of the progress in the modification of semiconductors by proton beams in fields such as proton-enhanced diffusion, ion-beam mixing, and formation of porous layers. This method of modification (doping) is shown to have high potential in monitoring the properties of semiconductor materials and designing devices of micro and nano ele...

Analysis is given of the progress in the modification of semiconductors by proton beams in fields such as proton-enhanced diffusion, ion-beam mixing, and formation of porous layers. This method of modification (doping) is shown to have high potential in monitoring the properties of semiconductor materials and designing devices of micro and nano ele...

Steady-state and transient forward current-voltage I-V characteristics have been measured in 5.5 kV p⁺-n-n⁺ 4H-SiC rectifier diodes up to a current density j≈5.5×10 ⁴ A/cm². The steady-state data are compared with calculations in the framework of a model, in which the emitter injection coefficient dec...

Process induced deep level donor centers in Si, who play a key role in limiting of p-n junction breakdown voltage have been identified as isolated sulfur centers. The identification was done with the help of capacitance transient experiments in diodes with n- and p-type base, measurements of hole capture cross section of signly ionized middle gap D...

Three types of fabrication cycle based on the use of direct wafer bonding are developed for making pairs of discrete p-n-junctions separated by an insulating layer. The forward and reverse branches of the I–V characteristics of the resulting diodes are investigated. For all three fabrication cycles, the differential resistance of the forward branch...

Three types of fabrication cycle based on the use of direct wafer bonding are developed for making pairs of discrete p-n-junctions separated by an insulating layer. The forward and reverse branches of the I–V characteristics of the resulting diodes are investigated. For all three fabrication cycles, the differential resistance of the forward branch...

Electron paramagnetic resonance (EPR) spectra of radiation defects induced by low-energy protons (100 keV) in a thin near-surface layer (L<1 μm) of silicon crystals are detected with spin-dependent microwave photoconductivity. It is found that EPR spectra of the excited triplet states of oxygen+vacancy complexes and spectra related to carbon-contai...

The distribution of hydrogen in Si and SiC following high-temperature proton irradiation (T irr=20–700 °C) is studied by secondary-ion mass spectrometry. It is shown that the hydrogen concentration profile in SiC depends weakly on irradiation temperature. In Si appreciable alteration of the concentration profile is observed already at T irr⋍300 °C,...

The method of spin-dependent recombination was used to record electron spin resonance (ESR) spectra of recombination centers in a thin (∼1 µm) surface layer of p-type silicon grown by the Czochralski method and irradiated by protons with energies of ∼100 keV. Spectra of excited triplet states of the oxygen + vacancy complex (A-centers) were observe...

Deep-level defects appear in silicon upon heat treatment of wafers with surface disordered by mechanical lapping or introducing high concentration impurity in diffusion layer, i.e. in regimes typical of fabrication of high voltage devices. By means of capacitance transient spectroscopy, combined with other methods, it was shown that dominant electr...

A technology based on ion implantation and the direct wafer bonding of p +-p-n + structures has been developed for multijunction silicon solar cells. The internal quantum efficiency of such structures is close to unity in the wavelength range 350–900 nm.

The possibility of solid-phase direct bonding of silicon wafers having p +-or n +-type diffusion layers with a high surface dopant concentration has been demonstrated for the first time.

The capabilities of acoustic microscopy in studying the internal structure of solid materials have been demonstrated. Experimental results for semiconductor devices have been presented that show the possibilities of obtaining high resolution acoustic images at high frequencies 0,8-1,5 GHz in studying multilayer structures lying deep below the surfa...

The capabilities of acoustic microscopy in studying the internal structure of solid materials have been demonstrated. Experimental results for semiconductor devices have been presented that show the possibilities of obtaining high resolution acoustic images at high frequencies 0,8-1,5 GHz in studying multilayer structures lying deep below the surfa...

Рассматриваются преимущества метода протонного облучения для повышения быстродействия кремниевых приборов тиристорного типа.Экспериментально показано, что протонное облучение РВД со стороны анода позволяет получить приборы с рекордным сочетанием основных параметров-блокируемое напряжение , время выключения , остаточное напряжение. Предполагается, ч...

Defects and electro-physical parameters DWB-semiconductor structures were studied by STM, LSM, SAM and TEM techniques.Some new practical and methodological aspects of the Scanning Microscopy Technique applications for characterization of DWB fabrication method and defect examination of DWB- device structures are presented.

We have identified a p-type layer on both sides of the interface formed by two directly bonded silicon wafers. The thickness and the hole concentration of the p-layer vary with the pretreatment of the wafer surface, temperature and bonding time. It is shown that the p-layer is formed by the diffusion of uncontrollable Al impurities adsorbed on the...

Silicon irradiated with high-energy heavy particles creating disordered regions, contains divacancies as one of the main radiation defects governing the generation - recombination parameters of silicon devices. However, the kinetics of annealing of divacancies in disordered regions, in defect-impurity shells around these regions, also in the undist...

We have identified a p-type layer on both sides of the interface formed by two directly bonded silicon wafers. It is shown that the p-layer is formed by the diffusion of uncontrollable Al impurities adsorbed on the hydrophilic silicon surface. The layer is responsible for the barrier properties of the interface in n+-n and n-n structures and for a...

The use of the silicon direct splice (SDS) method is analysed and the experimental research results for SDS technology have been presented. It is pointed out that the technology of solid phase SDS provides comparatively simple forming of p-n, n-n structures of large area with electrophysics parameters of semiconducting layers required. The use of t...

Исследованы статические и динамические характеристики запираемых тиристоров, подвергнутых облучению протонами с энергиями от 1 до 6 МэВ и дозами от 10Е10 до 10Е12 прот./кв. см. Показано , что создание зон повышенной рекомбинации вблизи эмиттерного p+n перехода позволяет существенно снизить динамические потери мощности тиристоров при выключении за с...

The paper lists the experimental results of studying fundamental electric characteristics of turn-off thyristors (CT), which fabrication involved the regulation of charge carriers lifetime by high energy proton implantation. The results confirmed, that the achievement of higher recombination at anode p-n transition of turn- off thyristor is an effi...

С помощью лазерного сканирующего микроскопа проведено исследование интерфейса полупроводниковых структур, сформированных методом прямого сращивания зеркально полированных кремниевых пластин. Показано , что измерение величины оптического пропускания структур при зондировании светом с длиной волны 1.15 мкм обеспечивает неразрушающий контроль однород...

Показано, что фммиачная гидрофилизация перед прямым сращиванием кремниевых пластин позволяет значительно уменьшить концентрацию глубоких центров в готовых структурах, повысить пробивное напряжение p-n переходов и более перспективна для изготовления мощных приборов методом ПСК, чем гидрофилизация с помощью H2SO4.

Using N-type silicon wafers (, 40 mm diameter and 3.5 mm thickness) P−N junctions with a breakdown voltage exceeding 20 kV have been manufactured.Applying a combination of slow-heating, slow-cooling and using polished float-zone Si and phosphorous silicon oxide glass layers for gettering the thermal defects, it was possible to avoid a change in res...

The results of studies of p-n junctions produced on silicon with a resistivity to 2 kohm· cm are presented. It is demonstrated that during production of p-n junctions in silicon thermal defects are formed that are responsible for a reduction in breakdown voltage of the junctions. An investigation of the formation of donor thermal defects in silicon...