Photosensitive structure and selective photodetector based thereon

FIELD: physics.

SUBSTANCE: in a photosensitive structure, which is a multilayer semiconductor heterostructure which is sensitive to terahertz radiation at effective photocurrent temperature, said heterostructure having a quantum well in form of a layer of a narrow-bandgap solid solution containing Hg and Te and enclosed between barrier layers of a wide-bandgap three-component solid solution of CdyHg1-yTe, where y is a value preferably in the range from 65% to 72%, the narrow-bandgap quantum well is formed from a three-component solid solution of Hg1-xCdxTe with content of Cd defined by a value x in the range from 4% to 12%, wherein the width of the quantum well is selected for the given terahertz frequency subrange of the received radiation at temperature of 4.2 K or 77 K depending on content of Cd in accordance with table 1 given in the claim. When the disclosed photosensitive structure is made as a desired terahertz photodetector - selective photodetector, in the latter, having a terahertz radiation sensitive photodetector line, which is in form of saeries-arranged areas of a multilayer semiconductor heterostructure having effective photosensitivity in different terahertz subranges at temperature of 4.2 K or 77 K, said areas having a working detector layer on a quantum well formed from a narrow-bandgap three-component solid solution of Hg1.xCdxTe and enclosed between barrier layers of a wide-bandgap three-component solid solution of CdyHg1-yTe, where y is a value preferably in the range from 65% to 72%, and a means of maintaining said temperature, for areas of the multilayer semiconductor heterostructure with selected terahertz frequency subranges of the received radiation, given by the following intervals of energy values of the received radiation ħω: 8-16, 16-24, 24-32, 32-40, 40-48, 48-56, 56-64 meV, the width of the quantum well is equal to 11 nm with content of Cd in the working detector layer on the quantum well - Hg1-xCdxTe on series-distributed areas of the photodetector line in accordance with said terahertz frequency subranges of the received radiation at temperature of 4.2 K, defined by the following intervals of values x, respectively: 7.1-7.9, 7.9-8.7,8.7-9.4,9.4-10.1, 10.1-10.9, 10.9-11.5, 11.5-12.2%, or at temperature of 77 K, defined by the following intervals of values x, respectively: 5-5.9, 5.9-6.7, 6.7-7.5, 7.5-8.3, 8.3-9.0, 9.0-9.8, 9.8-10.5%.

EFFECT: invention improves manufacturability of desired terahertz photodetectors by creating structural conditions for operation of the photodetector element on the level of stable high sensitivity in different subranges in a wide frequency range of the terahertz received radiation depending on the width of the quantum well.

3 cl, 2 tbl, 2 dwg

 

Group of inventions relates to nanooptoelectronics, in particular to a photosensitive solid-state nanostructures, namely, the technological Arsenal microphysical material means in the form of usovershenstvovannyh quantum-dimensional structures based on three-component solid solution CdHgTe, increase the efficiency of their application in photodetector devices for quantum wells in the terahertz range.

The modern trend in the field of solid-state photosensitive semiconductor structures, presents a three-component solid solution CdHgTe, is relevant due to the high sensitivity and resolution photodetectors based on the photosensitive material in a wide infrared range accept limits (see article A.Rogalski "HgCdTe infrared detector material: history, status and outlook" Rep. Prog. Phys. 68 (2005) 2267-2336).

However, a practical problem in the field of creation of new types of receivers terahertz radiation photodetector element in the form of a photosensitive semiconductor multilayer heterostructures based on three-component solid solution CdHgTe having a working crystal layer with properties of quantum wells, characterized by technological instability quality photodetecting element expressed in volatility (range) sensitivity in different host cells such photodetectors.

Not devoid of this shortcoming and is known photosensitive structure (see .Grein, .Jung, R.Singh and M.FIatte "Comparison of normal and inverted band structure of HgTe/CdTe superlattices for very long wavelength infrared detectors" Journal of Electronic Materials, v. 43, No. 6, 2005, p.905-908), selected by the applicant as a prototype of the inventive photosensitive patterns and representing sensitive to terahertz radiation at a temperature effective photocurrent multilayer semiconductor heterostructure with quantum pit made in the form of narrow-gap layer of a solid solution containing Hg and Those concluded between barrier layers of wide bandgap ternary solid solution CdyHg1-yTe, where y is the value in the preferred range from 65% to 72%.

The task of the claimed group of inventions is the development of technological capabilities of the instrumentation in the field of terahertz photodetectors in the development of an improved sensitive to terahertz radiation multilayer semiconductor heterostructures with quantum pit made in the form of narrow-gap layer of solid solution Hg1-xCdxTe and characterized by a stable distribution of high sensitivity photodetector element in the set of THz frequency sub-bands received radiation at a temperature effective photocurrent could be the value from the width of the quantum well and composition specified solid solution.

The technical result of the claimed group of inventions - improving the manufacturability of the target terahertz photodetectors by creating structural conditions photodetector element at the level of stable high sensitivity in different sub-bands in a wide range of terahertz frequencies received radiation at a temperature of 4,2K or between 77K depending on the width of the quantum well thickness working crystal layer made of a ternary solid solution Hg1-xCdxTe and Cd content (value of x) in the interval from 4% to 12%.

To achieve the technical result in a photosensitive structure representing sensitive to terahertz radiation at a temperature effective photocurrent multilayer semiconductor heterostructure with quantum pit made in the form of narrow-gap layer of a solid solution containing Hg and Te and entered into between the barrier layers of the broad-band three-component solid solution CdyHg1-yTe, where y is the value in the preferred range from 65% to 72%, narrow-gap layer of the quantum well is formed from a three-component solid solution Hg1-xCdxTe with Cd content determined by the value of x in the interval from 4% to 12%, and the width of the quantum well selected the La given terahertz frequency subband received radiation at a temperature of 4,2K or between 77K depending on the content of the Cd in accordance with table 1, given below in the description.

To achieve the technical result in the case of the proposed photosensitive patterns in the form of targeted terahertz photodetecting devices - selective photodetector device, the latter containing sensitive to terahertz radiation photodetector line representing sequentially distributed and having an effective photosensitivity in various THz sub-bands at a temperature of 4,2K or between 77K areas multilayer semiconductor heterostructure with a working crystal layer on the quantum well formed of narrow-gap ternary solid solution Hg1-xCdxTe and lies between the barrier layers of the broad-band three-component solid solution CdyHg1-yTe, where y is the value in the preferred range from 65% to 72%, and a means of maintaining the specified temperature, for areas multilayer semiconductor heterostructure with a dedicated terahertz frequency sub-bands received radiation, asked the following intervals of values of the energy received radiation ħω: 8-16, 16-24, 24-32, 32-40, 40-48, 48-56, 56-64 MeV, the width of the quantum well is equal to 11 nm when the content of the Cd in a working crystal layer on the quantum well - Hg1-xCdxTe to follow is consequently distributed sites of a one-dimensional line in accordance with the specified terahertz frequency sub-bands received radiation at a temperature of 4,2K, defined, respectively, by the following intervals of values of x: 7.1-7.9, 7.9-8.7, 8.7-9.4, 9.4-10.1, 10.1-10.9, 10.9-11.5, 11.5-12.2%, or at a temperature of 77°K, defined respectively by the following intervals of values of x: 5-5 .9, 5.9-6.7, 6.7-7.5, 7.5-8.3, 8.3-9.0, 9.0-9.8, 9.8-10.5%.

In the particular case of the implementation of selective photodetection device areas multilayer semiconductor heterostructure with a working crystal layer on the quantum well each made in the form of bipolar sequentially formed on the GaAs substrate (013) layers: base layer - ZnTe buffer layer of CdTe, double barrier quantum-well layers - Cd0.7Hg0.3Te located between the mentioned work rectifying layer Hg1-xCdxTe and the top layer is CdTe.

Figure 1 shows a diagram of the inventive photosensitive patterns, figure 2 - diagram of the inventive selective photodetection device.

We offer a photosensitive structure in the example (see figure 1) contains bipolar sequentially formed on a substrate 1 of GaAs (013) layers: a base layer 2 - ZnTe buffer layer 3 - CdTe, the lower barrier quantum-well layer 4 , and a working crystal layer 5 - Hg1-xCdxTe upper barrier quantum-well layer 6 and the covering layer 7 - CdTe, and the thickness of the working detector layer (width of the quantum well) is selected for the required teraherz the th subband of frequencies of the received radiation, asked by intervals of values of the energy received radiation ħω, at a temperature effective photocurrent 4,2K or 77 K, depending on the content of the Cd in a working crystal layer quantum well (size x), specified in table 1.

We offer a photosensitive structure with the physical manifestation mechanism of photosensitivity working crystal layer 5 - quantum wells, similar to the process of excitation of interband transitions in a known photodetector (see, for example, the book SSI. Physics of semiconductor devices. - Moscow, Mir, 1984, Tom, s-340)provides for the allocation of zones of optimal implementation of the target photodetectors based on it. While the inventive photosensitive structure on the basis of a working crystal layer on the quantum well formed of narrow-gap ternary solid solution Hg1-xCdxTe, characterized by the parameters in table 1, expands the design possibilities of a one-dimensional instrument in the establishment of production and technological base structural modeling of the expected properties of a one-dimensional elements with a high degree of certainty.

So, for example, to create a photodetector device with sensitivity in the frequency domain detected signal 3 THz (12 MeV using table 1 (see string: 8-16 MeV) allows job growth parameters (composition and width of the active layer is a quantum well) in the manufacture of the specified device. In this case, the width of the formed layer may vary depending on the process conditions in the interval from 8 to 11 nm. Thus, for manufactured photodetector structures using the table is set to the calibrated set of parameters required during technological development growth of high-quality structures.

To achieve a workable multilayer photosensitive heterostructures based on Hg1-xCdxTe/CdyHg1-yTe with high quantum efficiency you want to use a work detector layer with the "non-inverted" band structure, i.e. in the case of HgTe quantum wells (photosensitive structure - prototype) layer thickness Kant hole should be less than 6.3 nm. However, the technology of producing such layers has an error of growth ~0.5 nm, that is 8%, which provides a sufficiently large variation of parameters in the manufacture of structures. In addition, the small thickness of the layer increases the scattering at the interface and reduces the mobility of carriers, which reduces the photosensitivity of the structure.

To solve these problems in this application is proposed to form the bipolar layer quantum pit is e of pure HgTe, and from Hg1-xCdxTe, that is, of the three-component solid solution with some degree of Cd. Dosed adding a Cd into a working crystal layer makes it possible to increase the thickness of the specified layer (the width of the quantum well), while providing the same value of the band gap energy (and hence the same energy received terahertz radiation), which in operation the detector layer of pure HgTe. Manufacturer wider quantum wells allows to reduce the influence of scattering on the interface and increase the mobility of carriers working layer, and therefore the sensitivity of the photodetector element.

Outlined features implemented in the proposed selective photodetection device (see figure 2), containing sensitive to terahertz radiation photodetector line 8, which represents a consistently distributed and having an effective photosensitivity in various THz sub-bands at a temperature of 4,2K or between 77K areas multilayer semiconductor heterostructure with a working crystal layer on the quantum well formed of narrow-gap ternary solid solution Hg1-xCdxTe and lies between the barrier layers of the broad-band three-component solid solution CdyHg1-yTe, where y is the value in the preferred range from 65% is about 72%, and the means of maintaining the specified temperature of the cryostat 9.

For areas specified multilayer semiconductor heterostructure with a dedicated terahertz frequency sub-bands received radiation, asked the following intervals of values of the energy received radiation ħω: 8-16, 16-24, 24-32, 32-40, 40-48, 48-56, 56-64 MeV, the width of the quantum well is equal to 11 nm (optimal from the point of view of providing a stable high sensitivity on the sites of a one-dimensional line) when the content of the Cd in a working crystal layer on the quantum well - Hg1-xCdxTe-sequential distributed sites of a one-dimensional line 8 in accordance with the specified terahertz frequency sub-bands received radiation at a temperature of 4,2K, defined respectively by the following intervals of values of x: 7.1-7.9, 7.9-8.7, 8.7-9.4, 9.4-10.1, 10.1-10.9, 10.9-11.5, 11.5-12.2%, or at a temperature of 77°K, defined respectively by the following intervals of values of x: 5-5 .9, 5.9-6.7, 6.7-7.5, 7.5-8.3, 8.3-9.0, 9.0-9.8, 9.8-10.5%.

To a one-dimensional line 8, characterized by its multi-layered semiconductor heterostructures (line of photodetector elements in the form of a consistent set of photosensitive elements with a bandgap which increases in accordance with the intervals of values of the energy received radiation ħω areas of heterostruc is URS) connected multi-ohmmeter 10 (for example, several devices like card 2400 combined into a common data bus)connected to the computer 11.

Selective photodetector allows to determine the energy of the incident monochromatic radiation. Depending on the energy of the quanta of radiation incident on the device on the photosensitive areas photodetector elements; made on the basis of the proposed multilayer semiconductor heterostructure, the width of the forbidden zone which exceeds the energy of the incident radiation signal, the photocurrent will not occur, while at the photodetector elements, the width of the gap which is less than the quantum energy of the incident radiation will be observed signal photocurrent. The quantum energy of the incident radiation will correspond to the energy width of the forbidden zones of the photodetector element from which there is a signal in which the width of the forbidden zone of maximum.

The basis for the development of the proposed group of inventions were following estimated evaluation table 1.

The calculation of the band structure of the quantum well carried out in the framework of the four models based on the known method of envelope functions (see .G.Burt, J.Phys.: Condens. Matter 4, 6651 (1992)).

The electron wave function is thus presented in the form of decomposition on the Bloch functions of the band edges (k=0):

Ψmo> (r)=exp(ikxx+ikyy)jFj(z)uj(r).

Functions uj(r) selected the same as in the famous work (see article .G. Novik, A. Pfeuffer-Jeschke, T. Jungwirth, V. Latussek, .R. Becker, G. Landwehr, H. Buhmann, and L.W. Molenkamp, Phys. Rev. 72, 35321 (2005)) and are considered to be the same for all semiconductors, forming a heterostructure in accordance with the above method (see .G. Burt).

Envelopes of functions Fj(z) are searched as solutions of the Schrodinger equation with Hamiltonian 8×8, taking into account the integrated deformation:

(H11(kx,ky,k^z)...H18(kx,ky ,k^z)H81(kx,ky,k^z)...H88(kx,ky,k^z))(F1(z)F8(z))=E(kx,ky)(F1(z) F8(z))

In the calculations we used the following Hamiltonian:

where

k±=kx±iky

kz=-iz

T=Ev+Eg+22m0[(2F+1)(kx2+ky2)+kz(2F+1)kz]+ac(2εxx+εzz),

U=Ev-22m0[γ1( kx2+ky2)+kzγ1kz]+av(2εxx+εzz),

V=-22m0[γ2kx2+(2350γ2+2750γ3)ky2-1825ky{γ2-γ3,kz}-kz(7350γ2+2750γ3)kz]++(73100b+ 93100d)(εxx-εzz)+(1825b-6325d)εyz

R=-22m03[-γ2kx2+2iγ3kxky+γ2kx2+(4150γ2+950γ3)ky2+

+625ky{(γ2-γ3),kz +950kz(γ2-γ3)kz]+

+(9100d-93100b)(εxx-εzz)+(6325b-625d)εyz

S±=-22m03[kx{γ3,kz}+kx{κ,kz}±12i25(γ2-γ 3)ky2±i25ky{(16γ3+9γ2),kz}±

±iky{κ,kz}12i25kz(γ2-γ3)kz]±6i25(3b-d)(εxx-εzz)±i25(93b+16d)εyz

S±=-22m03[k {γ3,kz}-13kx{κ,kz}±12i25(γ2-γ3)ky2±i25ky{(16γ3+9γ2),kz}

13iky{κ,kz}12i25kz(γ2-γ3)kz]±6i25(3b-d)(εxx-εzz) ±i25(93b+16d)εyz

C=2m0k-[κ,k^z].

The "+" symbol as a Superscript denotes Hermitian conjugation.

The expression for the Hamiltonian heterostructures grown on plane (013), was obtained by the method described in the work (see article J.Los, A.Fasolino, A.Catellani, Phys. Rev. 53, 4630 (1996)). Tensor components embedded deformation for the layer lattice constant and in the case of (013) is calculated by the following formulas:

εxx=εyy=a0-aa, εxz=0,

εyz=12(C11+2C12) (C12-C11+2C44)9C112-9C122+C44(82C11-18C12)εxx,

εzz=-9C112+18C11(C12-C44)-27C122+146C44C129C112-9C122+C44(82C11-18C12)εxx,

where a0- the lattice constant of the buffer layer, and the coordinate axes x, y and z direction is received along the (100), (0 3-1) and (013), respectively. When used for calculations of the band parameters of the materials of the above work (see article .G.Novik and others) and the values of the elastic moduli Cijof work (see K. Takita, K. Onabe, S. Tanaka, Phys. Stat. Sol. (b) 92, 297 (1997)). However, depending on the concentration of the solid solution are considered to be linear for all values except the width of the forbidden zone. It uses the formula of the work (see article .R. Becker, V. Latussek, A. Pfeuffer-Jeschke, G.Landwehr, and L.W. Molenkamp, Phys. Rev. In 62, 10353 (2000)).

Values for these parameters are shown in table 2.

Table 2
CdTeHgTeHg1-xCdxTe
EgMeV1606-303H-303(1-x)-h(1-x)
and, Å6.486.46ACdTex+AHgTe(1-x)
EvMeV-5700
Δ, MeV9101080
F -0.090
P, MeV·Å96.9596.95
γ11.474.1
γ2-0.280.5
γ30.031.3
κ-1.31-0.4
acMeV-2925-2380
avMeV01310
b, MeV-1200-1500
d, MeV-5400-2500
With11, 1011Dyne/cm25.625.92
With12, 1011Dyne/cm23.944.14
C44, 1011Dyne/cm22.062.1

To calculate the envelope functions and the corresponding values of the electron energy structure is presented in the form of a superlattice of loosely coupled quantum wells. The lattice period L is selected such that the interaction of nm had no significant effect on the energy spectrum. The calculations are carried out by the decomposition of the envelopes of the wave function in plane waves:

Fj(z)=n=-NNfj(n)1Lexp(i2πnLz),

where N specifies the maximum wavenumber used in the decomposition of (total number of elements in the basis is equal to 2N+1).

1. Photosensitive structure representing sensitive to terahertz radiation at a temperature effective photocurrent multilayer semiconductor heterostructure with quantum pit made in the form of narrow-gap layer of a solid solution containing Hg and Those concluded between barrier layers of wide bandgap ternary solid solution CdyHg1-yTe, where y is the amount which in the preferred range from 65% to 72%, characterized in that the narrow-gap layer of the quantum well is formed from a three-component solid solution Hg1-xCdxTe with Cd content determined by the value of x in the interval from 4% to 12%, and the width of the quantum well selected for a given terahertz frequency subband received radiation at a temperature of 4.2°K and 77°K, depending on the content of the Cd in accordance with table 1 in the specification.

2. Selective photodetection device containing sensitive to terahertz radiation photodetector line representing sequentially distributed and having an effective photosensitivity in various THz sub-bands at a temperature of 4.2°K and 77°K plots multilayer semiconductor heterostructure with a working crystal layer on the quantum well formed of narrow-gap ternary solid solution Hg1-xCdxTe and lies between the barrier layers of the broad-band three-component solid solution CdyHg1-yTe, where is the value in the preferred range from 65% to 72%, and a means of maintaining the specified temperature, characterized by the fact that for areas multilayer semiconductor heterostructure with a dedicated terahertz frequency sub-bands received radiation, asked the following inter is Alami quantities of energy received radiation ħω: 8-16, 16-24, 24-32, 32-40, 40-48, 48-56, 56-64 MeV, the width of the quantum well is equal to 11 nm when the content of the Cd in a working crystal layer on the quantum well - Hg1-xCdxTe-sequential distributed sites of a one-dimensional line in accordance with the specified terahertz frequency sub-bands received radiation at a temperature of 4.2 K, defined respectively by the following intervals of values of x: 7.1-7.9, 7.9-8.7, 8.7-9.4, 9.4-10.1, 10.1-10.9, 10.9-11.5, 11.5-12.2%, or at a temperature of 77 K, defined respectively by the following intervals of values of x: 5-5 .9, 5.9-6.7, 6.7-7.5, 7.5-8.3, 8.3-9.0, 9.0-9.8, 9.8-10.5%.

3. Selective photodetector according to claim 2, characterized in that the sections of the multilayer semiconductor heterostructure with a working crystal layer on the quantum well each made in the form of bipolar sequentially formed on the GaAs substrate (013) layers: base layer - ZnTe buffer layer of CdTe, double barrier quantum-well layers - Cd0,7Hgfor 0.3Tewith located between the mentioned work rectifying layer Hg1-xCdxTe and the top layer is CdTe.



 

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1 dwg

FIELD: infrared detectors.

SUBSTANCE: proposed photodiode infrared detector has semiconductor substrate translucent for spectral photodetection region rays and semiconductor graded band-gap structure disposed on substrate;. graded band-gap structure has following layers disposed one on top of other on substrate end. Highly conductive layer of one polarity of conductivity and fixed forbidden gap width produced by heavy doping; layer of other polarity of conductivity and other forbidden gap width in the form of little hump whose value gradually rises from that corresponding to forbidden gap width of preceding layer and then, with smoother decrease to value corresponding to forbidden gap width of preceding layer or smaller. Working layer of same polarity of conductivity as that of preceding layer and fixed forbidden gap width equal to degree of final decrease in forbidden gap width of preceding layer and also equal to forbidden gap width in first of mentioned layer or smaller. Working layer is provided with p-n junction exposed at its surface. Layer disposed on working-layer p-n junction and having gradually increasing forbidden gap width to value corresponding to working layer and polarity of conductivity reverse to that of working layer.

EFFECT: maximized current-power sensitivity, enhanced maximal photodetection frequency, uniform parameters with respect to surface area.

12 cl, 2 dwg

FIELD: fiber-optic communications, data protection, telecommunications, large-scale integrated circuit diagnosing and testing, single molecule spectrometry, astronomy, and medicine.

SUBSTANCE: proposed device has substrate carrying contact pads, One strip is made of superconductor in the form of meander and its ends are connected to contact pads. Other, additional, semiconductor strip is connected in parallel with above-mentioned strip made in the form of meander. Additional strip is made of superconductor whose kinetic inductance is lower than that of strip made in the form of meander.

EFFECT: enhanced speed, sensitivity, and bandwidth of detector.

9 cl, 2 dwg

FIELD: chemistry.

SUBSTANCE: invention can be used in production of dense wear-resistant ceramic and solid electrolytes. The method of producing powder of a zirconium, yttrium and titanium composite oxide involves preparing a starting solution of nitrates, adding an organic acid and a titanium-containing compound into said solution, followed by heat treatment. The organic acid used is glycine in amount of 1.6-2.5 mol per 1 g-atom of the sum of metal cations (Zr+4+Ti+4+Y+3). The titanium-containing compound used is a hydrolysable titanium compound with the ratio Zr+4:Ti+4=(0.99-0.85):(0.15-0.01). The starting solution is further mixed with 30% hydrogen peroxide with the ratio H2O2:Ti+4=(4.7-12):1. The hydrolysable titanium compound used can be titanium tetrabutylate or titanium sulphate or titanium tetrachloride.

EFFECT: invention prevents waste discharge, reduces power consumption and simplifies production of nanopowder of a zirconium, titanium and yttrium composite oxide.

3 cl, 3 ex

FIELD: nanotechnologies.

SUBSTANCE: bombardment of a surface with an ion beam and recording of intensity of reflected ions is performed; besides, analysed surface is bombarded with inert gas ions with energy of less than 100 eV, and energy spectrum of reflected ions is recorded in the energy range, which is higher than energy of primary ions; then, as per energies of peaks of pair collision in the obtained spectrum there determined are types of atoms in one upper monolayer of atoms, as per the available peak with energy equal to energy of bombarding ions there evaluated is availability of a crystalline phase on amorphous or amorphised surface, including in a film of nanodimensional thickness, and as per the ratio of values of the above peak without any energy losses to a peak or peaks of pair collision there determined is surface concentration of crystalline phase on amorphous or amorphised surface.

EFFECT: reduction of depth of an analysed layer till sub-nanodimensional values; improvement of reliability of analysis results and enhancement of compatibility of equipment for implementation of the method with other analysis methods and process equipment.

2 dwg

FIELD: chemistry.

SUBSTANCE: solution for chemical deposition of a composite coating contains components in the following ratio, g/l: nickel chloride 15-25, sodium hypophosphite 15-25, sodium acetate 8-15, nanodiamond powder with particle size of 0.004-0.450 mcm 1-20, silver nitrate 0.5-2, 5% aqueous polyvinyl alcohol solution 0.5-2, fluoroplastic suspension F-4D 2-30 and distilled water - up to 1 l.

EFFECT: improved tribological properties and microhardness of the coating.

1 tbl, 1 ex

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention refers to chemical-pharmaceutical industry and medical equipment and may be used in preparing multifunctional biological active structures for the fixation of dressings and objects. The fixation device consists of a paper carrier made of cellulose and viscous fibres impregnated with a special preparation, dried; with its one side of the prepared carrier coated with an adhesive and with its other side coated with a primer and an adhesive.

EFFECT: improved drape effect, enhancement, easier and faster usage.

6 cl, 1 tbl, 2 ex

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to traumatology and orthopedics, and can be used for prevention of purulent-inflammatory complications from application of apparatuses of external fixation in the process of treatment of patients in traumatology and orthopedics. For this purpose transosseous osteosynthesis of long tubular bones is performed by introduction of wires and intraosseous rods of compression-distraction apparatus of external fixation into their proximal and distal fragments. Antimicrobial substance is applied on the surface of wires and intraosseous rods before their introduction into proximal and distal fragments, as well as on degreased surface of patient's skin in places of entrance and exit of wires and intraosseous rods. As antimicrobial means used is gel-like nanostructured composite implant. It is replaced on degreased surface of skin in places of entrance and exit of wires and intraosseous rods 2-4 weeks after initial application. Composite implant includes platelet-enriched autoplasma, mixed in ratio 1:1.0-2.0 with granules of complex alloplastic preparation on the basis of hydroxyapatite, which contains 50-60 wt % of collagen. Said complex alloplastic preparation additionally contains 0.08-2.8 wt % of colloid solution of zerovalent metal silver Ag0, or gold Au0, or copper Cu0, or palladium Pd0, or platinum Pt0, which is introduced into its granules at preparation stage. Size of introduced colloid zerovalent metal nanoparticles constitutes from 2 nm to 40 nm.

EFFECT: method ensures efficient prevention of purulent-inflammatory complications in such patients due to elimination of microbial risk of bacterial contaminations in treatment of patients by means of apparatuses of external fixation.

5 cl, 5 ex

FIELD: medicine.

SUBSTANCE: invention relates to traumatology and orthopedics and can be applied for surgical treatment for deforming arthritis of ankle joint. Cartilages are ablated from joint surfaces of shin tibia and talus. Cut of skin is performed on external surface in the area of injured ankle joint on posterior edge of external ankle-bone. After exposure of fibula from lower third to its top at the level of joint space of ankle joint oblique osteotomy of fibula is performed above anterior and posterior tibial-fibular and calcaneal-fibular ligaments at 40-50° angle to its longitudinal axis. Anterior and posterior tibial-fibular and calcaneal-fibular ligaments are transversely dissected to 1/3-1/2 of their width. Volume of space formed between joint arthrodised surfaces of tibia and talus is filled with gel-like nanostructured composite implant, which contains platelet-enriched autoplasma in ratio 1:(1-2) with granules of complex alloplastic preparation, based on hydroxyapatite, containing 50-60% of collagen.

EFFECT: method makes it possible to improve possibilities of bone regeneration stimulation.

4 cl, 3 ex

FIELD: physics.

SUBSTANCE: method involves evaporating a target of starting material with a pulsed electron beam with energy of not more than 100 keV, pulse duration of 20-300 mcs, energy density of not less than 1 MJ/cm2; a beam of electrons on the path to the target is passed through a system of generating a gas pressure drop, through which pressure of 1-20 Pa is provided in the evaporation chamber in order to cool particles, wherein particles are deposited on cooled substrates made of metal whose melting point is higher than 900°C, and the coefficient of linear thermal expansion is close to that of the deposited layer of aluminium oxide, the thickness of which is controlled in the range of 5-40 mcm by deposition time of 5-20 minutes, and radiation sensitivity is controlled by final heat treatment in the range of 550-900°C for 10-20 minutes.

EFFECT: high accuracy and reliability of detecting doses of short-range charged particles of nuclear radiations, including complex fields using TL or OSL techniques.

FIELD: chemistry.

SUBSTANCE: method involves obtaining a biocompatible coating on dental implants made of titanium and alloys thereof, which involves placing articles into an aqueous electrolyte solution containing potassium hydroxide and nanostructured hydroxyapatite in form of an aqueous colloidal solution, and exciting micro-arc discharges on the surface of the articles. The treated articles are oxidised in a chemical-resistant non-conducting bath: two batches of treated articles are simultaneously placed in the electrolyte solution by pre-attaching articles of one batch to terminals for treated articles, and articles of the other batch to terminals of an auxiliary electrode; and the electrolyte further contains sodium hydroxide, sodium hydrophosphate, liquid sodium glass, sodium metasilicate, in the following ratios, with respect to mass of dry substance in g/l of the composition: potassium hydroxide KOH - 2, sodium hydroxide NaOH - 1, sodium hydrophosphate Na2HPO4×12H2O - 5, liquid glass nNa2O·mSiO2 (M=3.2) - 5, sodium metasilicate Na2SiO3×9H2O - 8, nano-dispersed hydroxyapatite - 0.5-5. Deviation from said concentrations of electrolyte components does not exceed ±10%.

EFFECT: improved method.

1 tbl, 4 dwg, 1 ex

FIELD: chemistry.

SUBSTANCE: composition for making sensor coatings contains antimony-doped tin dioxide of the formula SbxSn1-xO2, where x=0.1-0.3, and water in ratio SbxSn1-xO2:H2O = 89-87:11-13 wt %. The method of preparing the composition involves hydrothermal treatment of tin and antimony hydroxides at 170°C for 48 hours. The tin and antimony hydroxides are obtained by dissolving Sn and Sb metal in concentrated hydrochloric acid, 18-20 wt %, while adding 3-5 wt % concentrated HNO3. The obtained solution is 2-3 times diluted with distilled water and a calculated amount of ammonia solution is added. Using a simple scheme, the disclosed method enables to obtain nanoparticles of said composition SbxSn1-xO2 with size of 30 nm and surface area of 154 m2/g, which can be used as the basic component of electroconductive ink for printing sensor arrays and microcontacts.

EFFECT: low labour and power consumption.

3 cl, 6 dwg, 3 ex

FIELD: chemistry.

SUBSTANCE: invention can be used in magnetic nanoelectronics for magnetic registering media with high recording density, for magnetic sensors, radio-absorbing screens, as well as in medicine. Method of obtaining magnetite nanoparticles, stabilised with polyvinyl alcohol, includes obtaining magnetite in alkali medium of mixture of salts of bi- and trivalent iron and polyvinyl alcohol with weight content in initial mixture from 4 to 18 wt %, dispersion, washing and carrying out all operations under continuous ultrasound impact. Process of sedimentation of salts of bi- and trivalent iron and polyvinyl alcohol is carried out in ammonia vapour, with application of aqueous ammonia (NH4OH) or hydrazine hydrate (N2H4·H2O).

EFFECT: invention makes it possible to reduce scatter of magnetite nanoparticles by size, reduce labour consumption and expenditures in the course of process.

2 dwg, 2 ex

Magnetic materials // 2244971

FIELD: magnetic materials whose axial symmetry is used for imparting magnetic properties to materials.

SUBSTANCE: memory element has nanomagnetic materials whose axial symmetry is chosen to obtain high residual magnetic induction and respective coercive force. This enlarges body of information stored on information media.

EFFECT: enhanced speed of nonvolatile memory integrated circuits for computers of low power requirement.

4 cl, 8 dwg

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