The studies of the influence of pico-second (4 × 10<sup>-13</sup> sec.) pulse electron irradiation with energy of 3.5 MeV on the electrical-physical properties of silicon crystals (n-Si) are presented...The studies of the influence of pico-second (4 × 10<sup>-13</sup> sec.) pulse electron irradiation with energy of 3.5 MeV on the electrical-physical properties of silicon crystals (n-Si) are presented. It is shown that in spite of relatively low electron irradiation energy, induced radiation defects are of cluster type. The behavior of main carrier mobility depending on temperature and irradiation dose is analyzed and charge carriers’ scattering mechanisms are clarified: on ionized impurities, on point radiation defects with transition into cluster formation. Dose dependencies of electrical conductivity and carrier mobility for samples of various specific resistivities are given.展开更多
Present paper describes the investigation of vacancy (V) and interstitial (I) annihilation on oxygen atoms by means of infrared (IR) absorption and Hall-effect measurements of the accumulation of vacancy-oxygen comple...Present paper describes the investigation of vacancy (V) and interstitial (I) annihilation on oxygen atoms by means of infrared (IR) absorption and Hall-effect measurements of the accumulation of vacancy-oxygen complexes (VO) in Si crystals at high energy electron irradiation. Silicon samples, containing along with isolated oxygen atoms, more complicated oxygen quasi-molecules of SiOn (n = 1, 2, 3…) type, were used. At isochronal and isothermal annealing in the temperature range of 300°C - 350°C, apart from the reaction of vacancy capturing by oxygen atoms with formation of A-centers, more complicated reactions with participation of vacancies and oxygen atoms were observed: A-centers, oxygen containing quasi-molecules. A model is suggested to describe the observed processes that are qualitatively different from those taking place in samples containing completely dissociated oxygen.展开更多
The results of experimental research of some effects in metal-insulator-semiconductor (MIS) structures induced by different types of radiation (50 MeV electrons, 12 keV gamma-quanta, 10 and 40 keV arsenic ions) are pr...The results of experimental research of some effects in metal-insulator-semiconductor (MIS) structures induced by different types of radiation (50 MeV electrons, 12 keV gamma-quanta, 10 and 40 keV arsenic ions) are presented. It is found that there is a significant difference between the characters of radiation surface states (SS) formed by ionization and impact actions of the MIS structure irradiation at the insulator-semiconductor (I-S) interface. It is shown that the SS generation rate is increased in electric fields and depends on the MIS structure field electrode material.展开更多
This paper reports results from an investigation of the interaction of displaced Si-self atoms (I) and their vacancies (V), with impurities in crystalline silicon (Si), as induced by micro-second pulse duration irradi...This paper reports results from an investigation of the interaction of displaced Si-self atoms (I) and their vacancies (V), with impurities in crystalline silicon (Si), as induced by micro-second pulse duration irradiation with electrons at different energies: 3.5, 14, 25 and 50 MeV and pico-second pulse duration with energy 3.5 MeV. V-V, I-impurity atom and V-impurity atom interactions are analyzed both experimentally and as modeled using computer simulations. A process of divacancy (V2) accumulation in the dose-dependent linear region is investigated. The effect of impurities on recombination of correlated divacancies, and I-atoms that had become displaced from regular lattice points is estimated by computer modeling of an appropriate diffusion-controlled process. It is concluded that the experimental results can be interpreted quantitatively in terms of a strongly anisotropic quasi-one-dimensional diffusion of displaced I-atoms. In addition, a significant difference is found between the effects of pico-second duration electron beam irradiation, which causes the formation of A-centre (V + Oxygen) clusters, while when the beam is applied on a micro-second timescale, divacancies are created instead, although the electrons have the same energy in both cases.展开更多
Study of spectral dependences of absorption coefficient at the region of absorption by free carriers shows that the introduction of radiation defects in n-GaP crystals leads to the appearance of additional scattering ...Study of spectral dependences of absorption coefficient at the region of absorption by free carriers shows that the introduction of radiation defects in n-GaP crystals leads to the appearance of additional scattering besides of traditional ones. A new scattering mechanism on “frozen” phonons (deformation localized near the radiation defects) is suggested and its behavior in experimental and theoretical aspects taking into account Х1с-Х3с transitions at the scattering process has been studied. It was shown that the increase of “frozen” phonons’ concentration results to the growth of this mechanism contribution in the whole scattering and the absorption coefficient by free carriers is described approximately by low α ~ ω-r, where -1/2 ≤ r ≤ 7/2. Suggested scattering mechanism allows explaining qualitatively the decrease of r. It was established that the dis- ordered by irradiation region effectively decreases the concentration of free carriers, but being a region of increased resistivity, it influences the scattering slightly even at the actual quantum region .展开更多
While considerable progress has been achieved in radiation influence on the solid states, the quantitative assessment of defect production is very scarce. In this paper radiation defects studies in silicon crystals ar...While considerable progress has been achieved in radiation influence on the solid states, the quantitative assessment of defect production is very scarce. In this paper radiation defects studies in silicon crystals are briefly reviewed and comprehensively analyzed depending on irradiation energy and dose, paying special attention to electron irradiation in wide energy spectrum when crystal lattice disordered regions (clusters) occur. Electron irradiation, which is a simple way to introduce intrinsic defects, was used as one of the most powerful techniques to study point and cluster defects which affect properties of semiconductors depending on irradiation energy. Fundamental aspects of radiation induced defects are discussed and it is shown that they bring information on the threshold energy for atomic displacement, on the recombination of vacancy—interstitial pair and mainly, on radiation defects cluster formation which essentially influences on the irradiating material properties. The determination of the irradiation critical dose and energy for the formation of homogeneous disordered regions (clusters) are detailed.展开更多
The recombination processes for charge carriers have been studied in n-type silicon crystals which were irradiated by pico-second duration pulse electrons with energy of 3.5 MeV (ultrafast irradiation), and maximum do...The recombination processes for charge carriers have been studied in n-type silicon crystals which were irradiated by pico-second duration pulse electrons with energy of 3.5 MeV (ultrafast irradiation), and maximum dose of 3.3 × 1013 el/cm2. In-situ measurements were carried out under artificial conditions simulating natural environment (space, semiconductor detectors, etc.). The observed phenomena were investigated experimentally in-situ using a high-speed oscilloscope equipped with a special preamplifier. Following irradiation to particular doses, some peculiarities of the recovery time of the semiconductor equilibrium condition (“characteristic time”), were obtained. Thus, it was found that the value of the “characteristic time” differs by an order of magnitude from the lifetime of the non-equilibrium (minority) charge carrier measured in an ex-situ regime. However, their behavior, as a function of irradiation dose, is similar and decreases with dose increase. Investigations of the dependencies of electro-physical parameters on irradiation dose, using Hall effect measurements, showed that at particular doses the radiation defects thus created, have an insignificant influence on the concentration of the charge carriers, but change their scattering properties appreciably, which affects the time parameters for the recombination of the semiconductor charge carriers. This investigation uses a novel approach to solid-state radiation physics, where in situ measurements were conducted in addition to conventional pre- and post-irradiation.展开更多
Equipment has been designed and created for experimental simulation of space environment conditions of Geostationary orbit of the Earth. The following conditions are supported in the vacuum chamber having volume of 1....Equipment has been designed and created for experimental simulation of space environment conditions of Geostationary orbit of the Earth. The following conditions are supported in the vacuum chamber having volume of 1.2 cubic meters: Vacuum 10-5 Torr. (1.3 × 10-3 Pa), electron beam with energy up to 8 MeV, temperatures from -150°C to +150°C and solar ultraviolet radiation. The peculiarity of this equipment is the possibility of analyzing complex simultaneous influence of mentioned above 4 factors on the sample and in-situ direct measurement of sample parameters under irradiation which provides almost real conditions. Silicon single crystals used in space environment were tested in the vacuum chamber and new results were received having scientific and applied interest. It was shown, particularly, that the electro-conductivity of silicon samples has higher value at in-situ condition than ex-situ after irradiation.展开更多
The influence of electron radiation on the properties of semiconducting silicon single crystals (Si)—both n- and p-types (currently one of the most widely applied material in the electronic technology) was studied un...The influence of electron radiation on the properties of semiconducting silicon single crystals (Si)—both n- and p-types (currently one of the most widely applied material in the electronic technology) was studied under the electron irradiation process in-situ in air (in common conditions). Higher value of electro-conductivity (σ) during the irradiation process with respect to after irradiation was observed, which was explained by ionization and capture mechanisms resulting in the formation of non-equilibrium carriers (hole-electron pairs). The kinetics of radiation defects generation, their physical nature, temperature stability and relaxation are examined. Structural radiation defects formation: point and complexes, their influence on the silicon conductivity are considered.展开更多
文摘The studies of the influence of pico-second (4 × 10<sup>-13</sup> sec.) pulse electron irradiation with energy of 3.5 MeV on the electrical-physical properties of silicon crystals (n-Si) are presented. It is shown that in spite of relatively low electron irradiation energy, induced radiation defects are of cluster type. The behavior of main carrier mobility depending on temperature and irradiation dose is analyzed and charge carriers’ scattering mechanisms are clarified: on ionized impurities, on point radiation defects with transition into cluster formation. Dose dependencies of electrical conductivity and carrier mobility for samples of various specific resistivities are given.
文摘Present paper describes the investigation of vacancy (V) and interstitial (I) annihilation on oxygen atoms by means of infrared (IR) absorption and Hall-effect measurements of the accumulation of vacancy-oxygen complexes (VO) in Si crystals at high energy electron irradiation. Silicon samples, containing along with isolated oxygen atoms, more complicated oxygen quasi-molecules of SiOn (n = 1, 2, 3…) type, were used. At isochronal and isothermal annealing in the temperature range of 300°C - 350°C, apart from the reaction of vacancy capturing by oxygen atoms with formation of A-centers, more complicated reactions with participation of vacancies and oxygen atoms were observed: A-centers, oxygen containing quasi-molecules. A model is suggested to describe the observed processes that are qualitatively different from those taking place in samples containing completely dissociated oxygen.
文摘The results of experimental research of some effects in metal-insulator-semiconductor (MIS) structures induced by different types of radiation (50 MeV electrons, 12 keV gamma-quanta, 10 and 40 keV arsenic ions) are presented. It is found that there is a significant difference between the characters of radiation surface states (SS) formed by ionization and impact actions of the MIS structure irradiation at the insulator-semiconductor (I-S) interface. It is shown that the SS generation rate is increased in electric fields and depends on the MIS structure field electrode material.
文摘This paper reports results from an investigation of the interaction of displaced Si-self atoms (I) and their vacancies (V), with impurities in crystalline silicon (Si), as induced by micro-second pulse duration irradiation with electrons at different energies: 3.5, 14, 25 and 50 MeV and pico-second pulse duration with energy 3.5 MeV. V-V, I-impurity atom and V-impurity atom interactions are analyzed both experimentally and as modeled using computer simulations. A process of divacancy (V2) accumulation in the dose-dependent linear region is investigated. The effect of impurities on recombination of correlated divacancies, and I-atoms that had become displaced from regular lattice points is estimated by computer modeling of an appropriate diffusion-controlled process. It is concluded that the experimental results can be interpreted quantitatively in terms of a strongly anisotropic quasi-one-dimensional diffusion of displaced I-atoms. In addition, a significant difference is found between the effects of pico-second duration electron beam irradiation, which causes the formation of A-centre (V + Oxygen) clusters, while when the beam is applied on a micro-second timescale, divacancies are created instead, although the electrons have the same energy in both cases.
文摘Study of spectral dependences of absorption coefficient at the region of absorption by free carriers shows that the introduction of radiation defects in n-GaP crystals leads to the appearance of additional scattering besides of traditional ones. A new scattering mechanism on “frozen” phonons (deformation localized near the radiation defects) is suggested and its behavior in experimental and theoretical aspects taking into account Х1с-Х3с transitions at the scattering process has been studied. It was shown that the increase of “frozen” phonons’ concentration results to the growth of this mechanism contribution in the whole scattering and the absorption coefficient by free carriers is described approximately by low α ~ ω-r, where -1/2 ≤ r ≤ 7/2. Suggested scattering mechanism allows explaining qualitatively the decrease of r. It was established that the dis- ordered by irradiation region effectively decreases the concentration of free carriers, but being a region of increased resistivity, it influences the scattering slightly even at the actual quantum region .
文摘While considerable progress has been achieved in radiation influence on the solid states, the quantitative assessment of defect production is very scarce. In this paper radiation defects studies in silicon crystals are briefly reviewed and comprehensively analyzed depending on irradiation energy and dose, paying special attention to electron irradiation in wide energy spectrum when crystal lattice disordered regions (clusters) occur. Electron irradiation, which is a simple way to introduce intrinsic defects, was used as one of the most powerful techniques to study point and cluster defects which affect properties of semiconductors depending on irradiation energy. Fundamental aspects of radiation induced defects are discussed and it is shown that they bring information on the threshold energy for atomic displacement, on the recombination of vacancy—interstitial pair and mainly, on radiation defects cluster formation which essentially influences on the irradiating material properties. The determination of the irradiation critical dose and energy for the formation of homogeneous disordered regions (clusters) are detailed.
文摘The recombination processes for charge carriers have been studied in n-type silicon crystals which were irradiated by pico-second duration pulse electrons with energy of 3.5 MeV (ultrafast irradiation), and maximum dose of 3.3 × 1013 el/cm2. In-situ measurements were carried out under artificial conditions simulating natural environment (space, semiconductor detectors, etc.). The observed phenomena were investigated experimentally in-situ using a high-speed oscilloscope equipped with a special preamplifier. Following irradiation to particular doses, some peculiarities of the recovery time of the semiconductor equilibrium condition (“characteristic time”), were obtained. Thus, it was found that the value of the “characteristic time” differs by an order of magnitude from the lifetime of the non-equilibrium (minority) charge carrier measured in an ex-situ regime. However, their behavior, as a function of irradiation dose, is similar and decreases with dose increase. Investigations of the dependencies of electro-physical parameters on irradiation dose, using Hall effect measurements, showed that at particular doses the radiation defects thus created, have an insignificant influence on the concentration of the charge carriers, but change their scattering properties appreciably, which affects the time parameters for the recombination of the semiconductor charge carriers. This investigation uses a novel approach to solid-state radiation physics, where in situ measurements were conducted in addition to conventional pre- and post-irradiation.
文摘Equipment has been designed and created for experimental simulation of space environment conditions of Geostationary orbit of the Earth. The following conditions are supported in the vacuum chamber having volume of 1.2 cubic meters: Vacuum 10-5 Torr. (1.3 × 10-3 Pa), electron beam with energy up to 8 MeV, temperatures from -150°C to +150°C and solar ultraviolet radiation. The peculiarity of this equipment is the possibility of analyzing complex simultaneous influence of mentioned above 4 factors on the sample and in-situ direct measurement of sample parameters under irradiation which provides almost real conditions. Silicon single crystals used in space environment were tested in the vacuum chamber and new results were received having scientific and applied interest. It was shown, particularly, that the electro-conductivity of silicon samples has higher value at in-situ condition than ex-situ after irradiation.
文摘The influence of electron radiation on the properties of semiconducting silicon single crystals (Si)—both n- and p-types (currently one of the most widely applied material in the electronic technology) was studied under the electron irradiation process in-situ in air (in common conditions). Higher value of electro-conductivity (σ) during the irradiation process with respect to after irradiation was observed, which was explained by ionization and capture mechanisms resulting in the formation of non-equilibrium carriers (hole-electron pairs). The kinetics of radiation defects generation, their physical nature, temperature stability and relaxation are examined. Structural radiation defects formation: point and complexes, their influence on the silicon conductivity are considered.
