Alexander A. Lebedev

Impact of high energy electron irradiation on high voltage Ni/4H-SiC Schottky diodes

We report the results of the high energy (0.9u2009MeV) electron irradiation impact on the electrical properties of high voltage Ni/4H-SiC Schottky diodes. Within the range of the irradiation dose from 0.2u2009×u20091016u2009cm−2 to 7u2009×u20091016u2009cm−2, electron irradiation led to 6 orders of magnitude increase in the base resistance, appearance of slow relaxation processes at pico-ampere current range, and increase in the ideality factor.

Effect of high energy electron irradiation on low frequency noise in 4H-SiC Schottky diodes

The low-frequency noise in high voltage Ni/4H-SiC Schottky diodes irradiated with high energy (0.9u2009MeV) electrons was studied in the frequency range from 1u2009Hz to 50u2009kHz, temperature interval 295–410u2009K, and irradiation dose Φ from 0.2u2009×u20091016u2009cm−2 to 7u2009×u20091016u2009cm−2. The noise amplitude was found monotonically increasing with the irradiation dose. With the irradiation dose increase, the noise spectra on the linear part of the current voltage characteristic transform from the 1/f noise to the generation recombination noise of at least two trap levels. One of these levels can be classified as Z1/2 with the capture cross section determined from the noise measurements to be ∼10−15 cm2.

SiC Schottky diode rectifier bridge represented as diffusion-welded stack

We considered the prototype of a SiC Schottky diode Rectifier Bridge made on the basis of commercial SiC Schottky diodes by diffusion welding (DW). Vertical integration for four diode chips in combination with molybdenum electrodes can improve the overall weight and dimensions of the module performance and increase device durability to radiation exposure. Our DW prototype, in contrast to commercial bridges, completely preserved the initial characteristics after irradiation by electrons with an energy of 0.9 MeV and density of 3 x 1016 cm-2

Degradation of 600-V 4H-SiC Schottky diodes under irradiation with 0.9 MeV electrons

In this paper investigation of degradation 4H SiC Schottky diodes parameters after irradiation by electrons with an energy of 0.9 MeV was doine. It was determined the carrier removal rate (Vd), which amounted to 0.07 - 0.09 cm-1. It is shown that the investigated Schottky diodes retained rectifying current-voltage characteristics of up to doses ~ 1017 cm-2. It is concluded that the radiation resistance of SiC Schottky diodes is much greater than the radiation resistance of Si p-i-n diodes with the same breakdown voltages

Effect of 3C-SiC irradiation with 8 MeV protons

Effects of proton irradiation in n-3C-SiC grown by sublimation on a 4H-SiC substrate have been studied by the Hall effect and photoluminescence methods. It was found that the carrier removal rate (Vd) reaches a value of ~110 cm-1. The full compensation of samples with an initial concentration of (1-2) x 1018 cm -3 was estimated to occur at doses of about 6 x 1015 cm -2. Compared with 4H and 6H silicon carbide, no significant increase in the intensity of so-called defective photoluminescence was observed in 3C-SiC.

Irradiation and annealing of p-type silicon carbide

The development of the technology of semiconductor devices based on silicon carbide and the beginning of their industrial manufacture have made increasingly topical studies of the radiation hardness of this material on the one hand and of the proton irradiation to form high-receptivity regions on the other hand. This paper reports on a study of the carrier removal rate (Vd) in p-6H-SiC under irradiation with 8 MeV protons and of the conductivity restoration in radiation- compensated epitaxial layers of various p-type silicon carbide polytypes. Vd was determined by analysis of capacitance-voltage characteristics and from results of Hall effect measurements. It was found that the complete compensation of samples with the initial value of Na - Nd ≈ 1.5 × 1018 cm−3 occurs at an irradiation dose of ∼1.1 × 1016 cm−2. It is shown that specific features of the sublimation layer SiC (compared to CVD layers) are clearly manifested upon the gamma and electron irradiation and are hardly noticeable under the proton an...

Electron-Diffraction Study of the Structure of Epitaxial Graphene Grown by the Method of Thermal Destruction of 6H- and 4H-SiC (0001) in Vacuum

The method of reflection high-energy electron diffraction (RHEED) is used for studying the structure of graphene layers formed on the surface of the Si-face of conductive and semi-insulating 6H- and 4H-SiC(0001) substrates by thermal desorption of Si atoms in high vacuum, depending on the temperature and time of sublimating Si atoms as well as depending on the method of preprocessing the substrate surface. Diffraction patterns are recorded in the

Effect of High Energy Electron Irradiation on Electrical and Noise Properties of 4H-SiC Schottky Diodes

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