Reception method of nanostructure silicon base plates
FIELD: physics; semiconductors.
SUBSTANCE: invention concerns processes of chemical machining of slices and can be used for creation of silicon bodies with nanosized structure, applicable as emitters of ions in analytical devices and for creation of light emitting devices. Essence of the invention consists in the reception method of nanostructure silicon base plates by processing of siliceous substances with a gas-vapor mix containing hydrofluoric acid and an oxidising substance, as an oxidising substance halogen or its mix with a oxygen-containing oxidising reagent taken in number of not less than 1.0% is used. Iodine can be used as halogen, and in quality of an oxygen-containing oxidising reagent - a reagent chosen from the group: ozone, peroxide, sulfuric acid, nitric oxide. The invention allows to Iodine can be used as halogen, and in quality of an oxygen-containing oxidising reagent - a reagent chosen from the group: ozone, peroxide, sulfuric acid, nitric oxide.
EFFECT: obtaining of base plates keeping stability of physical and chemical properties of a surface at long storage in natural conditions and providing high uniformity of physical and chemical properties of a surface and, accordingly, higher reproducibility of the analysis at use of such base plates.
8 cl, 6 dwg, 1 tbl
The invention relates to processes of chemical processing of semiconductor wafers and can be used to create silicon substrates with nanoscale structure is applicable as emitters ions in analytical instruments, in particular the mass spectrometer. The invention can also be used to create light-emitting devices.
A silicon substrate with a nanocrystalline structure have a number of properties that distinguish them from single-crystal and polycrystalline substrates. In particular, when the laser impact they can become highly effective emitter pre-ions adsorbed on their surface chemical compounds. This property is used in the method of surface-induced laser desorption-ionization (Surface Assisted Laser Desorption-Ionization or " SALDI"), in particular, in one of the most important variants of this method-desorption-ionization on silicon substrates [Alimpiev, S., Nikiforov, S., Karavanskii V., J. Sunner, "On the mechanism of laser induced desorption-ionization of organic compounds from etched silicon and carbon surfaces" J. Chem. Phys., 2001, V.115, P.1891-1901; Zhouxin Shen, John J. Thomas, Claudia Averbuj, Klas M. Broo, Mark Engelhard, John E. Crowell, M.G.Finn and Gary Siuzdak "Porous Silicon as a Versatile Platform for Laser Desorption/Ionization Mass Spectrometry" Anal. Chem, 2001, V.73, P.612-619]. Another property of silicon substrates with a nanocrystalline structure is an intense photoluminescence, which can be and is used to create light-emitting devices.
The formation of the silicon substrates with nanoscale structure is carried out, usually by electrochemical (anodic) etching of monocrystalline silicon in a solution containing hydrofluoric acid. On the back side of the silicon wafer pre-create ohmic contact, for example, by sputtering aluminum. When a positive potential on the silicon electrode (the anode)immersed in a solution containing hydrofluoric acid, flow multistage reactions of dissolution and recovery of silicon. The second electrode (cathode) is usually a platinum plate. The result of this treatment, the formed porous silicon material consisting of nanocrystals and pore size from one to hundreds of nanometers [.Bisi, Stefano Ossicini, L.Pavesi "Porous silicon: a quantum sponge structure for silicon based optoelectronics" Surface Science Reports, 2000, V.38, P.1-126].
A method of processing a silicon substrate for formation of a layer of porous silicon on the surface of the substrate, including anodic etching of n-si in the range of current density from 30 to 150 mA/cm2during the time from 20 to 600 min in concentrated hydrofluoric acid under illumination of the working surface of silicon, for example, an incandescent lamp with a capacity of 200-500 W [RF patent №1459542, CL H01L 21/306, publ. 06.10.2000,].
The known method procedureunrestricted porous silicon substrates by anodic etching in an electrolyte, containing hydrofluoric acid, ethanol and water [J.J.Thomas et al. Desorption-ionization on silicon mass spectrometry: an application in forensics, J. Analytica Chimica acta No. 442, 2001, p.185].
In the known method, the silicon substrate is placed in a Teflon cell with a 25% solution of hydrofluoric acid in ethanol and conduct anodic etching at a current density of 5 mA/cm2within 1 minute. Next, the substrate is treated with ozone followed by etching in a 5% solution of hydrofluoric acid in ethanol for 1 minute. The surface is then washed with ethanol.
However, known methods for producing silicon substrates with nanoscale structure by anodic etching in an electrolyte containing hydrofluoric acid, have the following drawbacks:
in the process of electrochemical etching is contamination of the silicon substrate by chemical substances, in particular alkali and alkaline earth metals. Mass spectra obtained by the use of such substrates as emitters ions, characterized by chemical noise that makes it difficult, and in some cases makes it impossible for detection of defined compounds;
- heterogeneity of the obtained silicon substrates with nanoscale structure. In particular, the local sensitivity (ionization efficiency) nonuniformly distributed over the surface that bring the low reproducibility of the analysis when using these substrates as the emitter ions. The heterogeneity of the substrate also leads to uncontrolled changes in the photoluminescence spectra obtained with different surface areas;
- the inability to store the substrate in aerobic conditions. Upon contact with the air is sufficiently rapid oxidation of the surface silicon atoms. Formed as a result of oxidation of the oxide layer is an insulator, which excludes the possibility of applying such a surface as the emitter of ions in analytical devices. When storing the substrate in aerobic conditions also rapid degradation photoluminescent properties. Therefore, when using silicon substrates prepared by a known method, an ion emitter or light emitting structures you can either use only freshly prepared samples, or during storage to take special measures to prevent contact of the substrate with air.
An additional disadvantage of known methods is the necessity of establishing electrical contact with the silicon substrate and electrochemical equipment, which complicates the process of obtaining nanostructured silicon substrates and increases their value.
The closest technical solution is the way to obtain nanostructured silicon substrates by arr the processing silicon-containing materials by gas-vapour mixture, containing vapors of nitric NGO3and HF hydrofluoric acid [M.Saadoun, N.Mliki, H.Kaabi, K.Daoudi, B.Bessais, H.Ezzaouia, R.Bennaceur "Vapour-etching-based porous silicon: a new approach" Thin Solid Films, 2002, V.405, P.29-34]. In the known method the silicon substrate is placed in a polypropylene cell partially filled with a mixture of NGO3(65%) and HF (40%), at a distance of 2.5 cm above the surface of the above-mentioned mixture. The cuvette is placed in a thermostat and maintain at a constant temperature. Gas-vapor mixture formed by the evaporation placed in the cuvette of nitric and hydrofluoric acids, reacts with the silicon substrate, resulting in the surface of the substrate layer is formed mesoporous silicon nanocrystalline structure. In the temperature range from 20°C to 30°C processing time of the substrate does not exceed 30 minutes, because when increasing the exposure time to completely violated the homogeneity of the porous layer. At a temperature of 40°With the processing of the substrate is 2 to 20 minutes At a temperature of 60°With the duration of treatment is limited to 2 minutes
In a known method of obtaining nanostructured silicon substrates latter is not in contact with solutions of acids, resulting in forming nanocrystalline porous layer is characterized by a high degree of purity. When using such substrates as emitters ion intensity hee the systematic noise is small and does not interfere with the detection of the analyzed compounds.
In addition, the known method does not involve the creation of electrical contact with the silicon substrate and electrochemical equipment that simplifies the method of obtaining nanostructured silicon substrates and reduces their cost.
However, the known method of obtaining silicon substrates with nanoscale structure has drawbacks:
- when processing a silicon substrate by a known method get though to a lesser extent than in counterparts, but still fairly large heterogeneity of the obtained silicon substrates with nanoscale structure. Different parts of the surface have substantially different physical and chemical properties. In particular, the local sensitivity (ionization efficiency) nonuniformly distributed over the surface, resulting in low reproducibility of the analysis when using these substrates as the emitter ions. In addition, they differ in the photoluminescence spectra obtained with different surface areas, which significantly complicates the use of such substrates in light-emitting devices.
- the inability to store the substrate in aerobic conditions. Like its competitors, when in contact with air is sufficiently rapid oxidation of the surface silicon atoms. Formed as a result of oxidation of the oxide is Loy is dielectric, that excludes the possibility of applying such a surface as the emitter of ions in analytical devices. When storing the substrate in aerobic conditions also rapid degradation photoluminescent properties. Therefore, when using silicon substrates prepared by a known method, an ion emitter or light emitting structures, you can either use only freshly prepared samples, or during storage to take special measures to prevent contact of the substrate with air.
The technical objective of the proposed solutions is to obtain nanostructured silicon substrates that remain stable physico-chemical properties of the surface during prolonged storage under natural conditions and providing higher compared to the prototype of the homogeneity of the physico-chemical properties of the surface and a higher reproducibility of the analysis when using such substrates as the emitter of ions in the methods of mass spectrometry and ion mobility spectrometry.
The technical problem is solved in that in a method of producing nanostructured silicon substrates by processing the silicon-containing material gas mixture containing hydrofluoric acid and an oxidizing agent, an oxidizing agent is used, the halogen is whether its mixture with oxygen-containing oxidizing reagent, taken in an amount not less than 1.0%.
Preferable as the halogen to use iodine, and as the oxygen-containing oxidizing reagent to use a reagent selected from the group of: ozone, hydrogen peroxide, sulfuric acid, oxides of nitrogen.
It is advisable to use a gas-vapor mixture obtained by mixing at a given temperature saturated vapor of iodine and equilibrium vapor of hydrofluoric acid and oxygen-containing oxidizing reagent.
It is advisable to use 5-50% aqueous solution of hydrofluoric acid, and the processing carried out when the temperature of the silicon-containing material 15-90°C.
Preferably the processing of silicon-containing materials to conduct the flow of gas mixture with temperaturas last 15-90°C.
Figure 1 presents a photograph in fluorescent microscope sample of nanostructured silicon, prepared by the method of the prototype.
Figure 2 - photograph of a fluorescent microscope sample of nanostructured silicon, prepared by the proposed method.
Figure 3 - the photoluminescence spectra of nanostructured silicon obtained by the method prototype. Spectra are taken under identical conditions with different surface areas.
Figure 4 - the photoluminescence spectra of nanostructured silicon obtained by the proposed the method. Spectra are taken under identical conditions with different surface areas.
Figure 5 is the Raman spectrum obtained on one of the sections of nanostructured silicon, prepared by the method of the prototype, and Raman spectra obtained at several sites nanostructured silicon, prepared by the proposed method.
Figure 6 - the Raman spectrum obtained on the second site of nanostructured silicon, prepared by the method of the prototype.
The use of halogen as an oxidant in the composition of the gas mixture (ASG) to obtain nanostructured silicon substrates allows retaining the benefits of steam etching, to improve the key parameters - uniformity and stability.
This is due to the significant difference in the mechanisms of oxidation of the silicon substrate pairs nitric acid (by way of a prototype) and halogen free (by the present method).
When exposed to nitric acid vapor, the formation of the oxide phase silicon SiO2, which then reacts with the hydrofluoric acid with the formation of volatile silicon tetrafluoride SiF4. When a certain ratio of the concentration of vapors of nitric and hydrofluoric acids formed nanostructured porous leucemia. However, different parts of such a layer can have a different structure and chemical composition. In particular, some areas may form ammonium nitrate as the product of the interaction of silicon with nitric acid (see figures 1, 5 and 6).
In addition, the surface of the formed layer is saturated with hydrogen, resulting in a main surface chemical groups of freshly prepared nanostructured silicon substrates are group Si-Hn(where n=1, 2, 3). These groups are in contact with air is quickly replaced with oxygen-containing groups, resulting on the surface of the silicon oxide layer is formed.
When used as an oxidizer vapor of the halogen oxidation mechanism is different, in particular, in the oxidation process does not result in formation of an oxide phase silicon SiO2. The halogen molecules adsorbed on the surface of a silicon substrate are efficient electron acceptors. Therefore, the adsorption of vapors halides leads to the formation of positively charged holes on the surface of a silicon substrate, and to provide reactivity of the silicon atoms in the interaction with pairs of hydrofluoric acid. The result is a nanostructured silicon layer with a high degree of uniformity and consistency of khimicheskogo the composition (see 2 and 5).
The surface of the formed layer is passivated by halogen and is chemically inert. Unlike the prototype of nanostructured silicon substrate obtained by the present method may be stored in contact with air without changing their chemical composition.
Thus, the halogen performs not only the function of the oxidizing agent, but also the function of the protective layer.
Below are examples of implementation of the proposed method.
At the bottom of the Teflon beaker with a volume of 100 ml was placed two containers with a volume of 15 ml each. The first tank is filled with an aqueous solution of hydrofluoric acid (25%), second - iodine. Teflon beaker is covered with a plate of monocrystalline silicon brand KES-0.01 at a distance of 2.5 cm above the surface of hydrofluoric acid and iodine are placed in a thermostat and incubated for 2.5 h at 40°C. in the volume of the Teflon Cup, free from placed two containers are formed saturated vapors of iodine and equilibrium pairs of hydrofluoric acid, which interact with the silicon substrate. As a result of such interaction on the surface of the silicon substrate layer is formed of nanocrystalline silicon with a thickness of about 1 μm.
At the bottom of the Teflon beaker with a volume of 150 ml was placed three volumes of 10 ml each. The first tank is filled with an aqueous solution of hydrofluoric acid (49%), second - iodine, and the third aqueous solution of hydrogen peroxide (10%). Teflon beaker is covered with a plate of monocrystalline silicon brand KES-0.005 at a distance of 3.5 cm from the top edge of the containers, placed in a thermostat and incubated for 2.5 h at 30°C. in the volume of the Teflon Cup, free from the three placed containers are formed saturated vapors of iodine and equilibrium pairs of hydrofluoric acid and hydrogen peroxide, which interact with the silicon substrate. As a result of such interaction on the surface of the silicon substrate layer is formed of nanocrystalline silicon with a thickness of about 1 μm.
In flow Teflon chamber is placed a monocrystalline silicon wafer mark KDB-0.01. The camera is at room temperature. Through the chamber pumped gas-vapor mixture obtained by mixing saturated at 40°C of iodine vapor and equilibrium at 20°C vapour 49% hydrofluoric acid and 5% sulfuric acid. The carrier gas is air, gas tract thermostatic at 40°C. for 30 minutes this treatment on the surface of the silicon substrate layer is formed of nanocrystalline silicon with a thickness of about 1 μm.
For detailed mapping of the main physico-chemical parameters characterizing the state of the surface, kremna the substrate s, obtained by the method of the prototype and the claimed method were analyzed by the methods of fluorescent spectroscopy, Raman spectroscopy and " SALDI " -mass spectrometry. The results obtained indicate that the substrate obtained by the claimed method differs from substrates prototype both in physical structure and chemical composition. Thus, large-scale heterogeneity patterns can be clearly seen on the photo luminescence samples of nanostructured silicon obtained by the method of the prototype (Figure 1), and absent in the samples prepared according to the claimed method (Figure 2). Additional information gives a comparison of the photoluminescence spectra taken from different places of the surface of nanostructured silicon, which was obtained by the method of the prototype (Figure 3, curves 1, 2 and 3). It is known that the intensity of photoluminescence and its range depends on the size of the silicon nanocrystallites and the chemical composition of the surface. The observed figure 3 differences in the intensity of photoluminescence, as well as the shift of the maximum of the spectrum shows significant small-scale heterogeneity patterns. At the same time nanostructured silicon layer obtained by the proposed method is characterized by a high degree of homogeneity and consistency of Henichesk the first composition. This, in particular, shows that the photoluminescence spectra taken from different places of the surface, is almost identical (Figure 4, curves 1, 2 and 3).
The difference in the chemical composition nanostrukturirovannogo silicon, prepared by the method of the prototype illustrates the Raman spectra taken from two different sites (Figure 5-6).
On the first plot (Figure 5) in the spectrum is observed only unbalanced line crystalline silicon 521 cm-1(a small broadening of the line in the region of smaller values of the shift indicates the formation of nanocrystallites). The second part of (6) in the spectrum there are a number of new lines that are apparently associated with the formation of the oxidized phase of silicon and ammonium nitrate (product of the interaction of nitric acid with silicon).
At the same time, all Raman spectra taken from different areas of nanostructured silicon obtained by the present method, had the form shown in Figure 5.
To compare the stability of nanostructured silicon substrates obtained by the method of the prototype and the proposed method, during prolonged storage under natural conditions, were also determined relative changes in the analytical signal. The results of one analysis are given in the table.
|The shelf life of the substrate, weeks||The relative change of the analytical signal from the substrate prepared by the method of the prototype, %||The relative change of the analytical signal from the substrate prepared by the present method, %|
From the data obtained it follows that the substrate obtained by the method of the prototype, quickly degrade, and after 5 weeks of the analytical signal is reduced more than 20 times. At the same time nanostructured silicon obtained by the present method, stable, and analytical signal accurate to measurement error does not change.
1. The method of obtaining nanostructured silicon substrates by processing the silicon-containing materials combined cycle is MESU, containing hydrofluoric acid and an oxidizer, wherein the oxidizer agents use halogen or a mixture of oxygen-containing oxidizing reagent, taken in an amount not less than 1.0%.
2. The method according to claim 1, characterized in that as the use of halogen iodine.
3. The method according to claim 1, characterized in that the use of oxygen-containing oxidizing reagent selected from the group of: ozone, hydrogen peroxide, sulfuric acid, oxides of nitrogen.
4. The method according to claim 1, characterized in that use gas-vapor mixture obtained by mixing at a given temperature saturated vapor of iodine and equilibrium vapor of hydrofluoric acid and oxygen-containing oxidizing reagent.
5. The method according to claim 1 or 4, characterized in that use 5-50%aqueous solution of hydrofluoric acid.
6. The method according to claim 1, characterized in that the treatment is carried out at a temperature of silicon-containing material 15-90°C.
7. The method according to claim 1, characterized in that the processing of silicon-containing materials lead the flow of gas mixture.
8. The method according to claim 1 or 7, characterized in that the processing of silicon-containing materials lead the flow of gas mixture with temperaturas last 15-90°C.
FIELD: technological processes.
SUBSTANCE: invention is related to technology of semiconductor instruments manufacture. Method for etching of aluminium film includes etching of aluminium film from the surface of siliceous plates by means of their processing in etchant, which contains nitric, phosphorous and acetic acids at the ratio of components that is accordingly equal to 1:50:12 at temperature of 40±5°C, for 15±5 minutes, at that difference in aluminium thickness layer makes 4.5÷5.0%.
EFFECT: provision of smooth profile relief and reduced time and temperature of etching.
FIELD: physics, semiconductors.
SUBSTANCE: invention is related to technology for making semiconductor instruments and integrated circuits, in particular, to methods for etching of film dielectrics, from which silicon nitride is most widely used. Invention makes it possible to get even relief of profile in process of plasma-chemical etching of silicon nitride films with quite high speed and repeatability of process. In method of plasma chemical etching of silicon nitride films, gas phase components are Freon and oxygen at the following ratio of components: Freon : O2=7 l/hr : 0.6 l/hr at working pressure of P=20±5 Pa and speed of 35±5 nm/min.
EFFECT: makes it possible to get even relief of profile in process of plasma-chemical etching of silicon nitride films with quite high speed and repeatability of process.
FIELD: physics, semiconductors.
SUBSTANCE: invention is related to technology for manufacture of semiconductor instruments and integrated circuits, in particular, to preparation of silicon plate surfaces prior to application of polyimide. Substance of invention: in method for treatment of plate surface prior to application of polyimide, treatment of silicon plate surface prior to application of polyimide is carried out in etchant that consists of hydrofluoric acid and acetone, at the following ratio of components: HF: CH3COCH3 = 1:100, time of silicon plate surface processing is equal to not more than 30 seconds at room temperature, number of dust specks makes 3 pieces.
EFFECT: provides for complete removal of different admixtures from surface of silicon plates, proper adhesion of polyimide to plate, reduction of temperature and time required for plate processing.
SUBSTANCE: method of silicon plate surface processing involves plate loading into bath filled by isopropyl alcohol and dirt cleaning at 25±5 Hz ultrasound frequency for 5±1 minutes. Control is performed under focused light by the number of luminescent points. Number of luminescent points should be below 5.
EFFECT: complete removal of dirt, prevention of silicon plate damage, chipping and fracture.
SUBSTANCE: method of photoresist removal involves photoresist film etching from silicon plates by processing in etching agent containing acetone and dimethylformamide. Photoresist film etching is performed at the following component ratio: acetone (CH3COOCH3) to dimethylformamide ((CH3)2NCOH), as 2:1 respectively at room temperature for 2±1 minutes. Cleaning control is performed in focused light beam, with luminescent point number not exceeding 5.
EFFECT: complete removal of photoresist, lower operation temperature, reduced etching duration.
FIELD: electrical engineering.
SUBSTANCE: semiconductor wafer intended for application in solar plants, in which uniform and fine structure of irregularities in the form of pyramid is provided evenly within the limits of its surface, and etching solution for generation of semiconductor wafer that has uniform and fine structure of irregularities. Semiconductor is etched with application of alkaline etching solution, which contains at least one type selected from the group that consists of carbonic acids, which have carbon number of 1-12 and have at least one carboxyl group in molecule, and their salts, so that in this manner structure of irregularities is formed on the surface of semiconductor surface.
EFFECT: safe and efficient method for manufacture of semiconductor wafer, which has perfect efficiency of photoelectric conversion, in which fine structure of irregularities suitable for application in solar element may be uniformly shaped with required size on the surface of semiconductor wafer.
12 cl, 16 dwg, 10 tbl
FIELD: processes, etching.
SUBSTANCE: usage: for receiving structures by means of plasma etching process through the mask. Concept of the invention: etching method of layer above support through the mask provides cyclic process of gases modulation during more then three cycles. Each cycle contains stage of protective layer formation operation implementation with usage of the first gaseous reagent with initial gaseous reagent, duration of which is preliminary 0.0055-7 seconds for each cycle, and stage of etching operation implementation for etching of device feature through the mask for etching of the second gaseous reagent using reactive gaseous reagent - etchant, duration of which is preliminary 0.005-14 seconds for each cycle. Protective layer formation operation contains stage of initial gas feeding and stage of plasma formation from initial gas. Each etching operation contains stage of reactive gas - etchant feeding and stage of plasma formation from reactive gas - etchant.
EFFECT: providing of regulation ability of critical dimensions during etching.
35 cl, 10 dwg
FIELD: instrument making.
SUBSTANCE: system for processing solid state devices incorporates head to feed processing fluid onto and withdraw it from the substrate surface, the head approaching the substrate surface to make certain gap there between. The system incorporates the first channel feeding, through the channel, the first fluid medium and the second channel for the second fluid medium, other than the first one, to be fed onto the substrate. The system comprises also the third channel to remove the aforesaid first and second fluids from the substrate surface, the channel being operated at a time with the two channels. The application describes also the method, the device and the head to the effect.
EFFECT: fast and efficient cleaning and drying of solid state substrates along with reducing traces of dirt being formed thereon.
27 cl, 21 dwg
FIELD: technological processes.
SUBSTANCE: invention concerns selective membrane production for molecular gas mix filtering and can be applied in compact fuel cells. Method of gas-permeable membrane production includes vacuum sputtering of a metal displaying chemical stability in concentrated hydrogen fluoride solutions in anode polarisation conditions onto monocrystalline silicon plate in closed pattern, and further double-side electrochemical etching of the plate area limited by the mentioned closed pattern. Etching process is performed until its spontaneous cease determined by break of time function curve of anode current on the plate surface not covered by sputtered metal.
EFFECT: increased thickness homogeneity of solid monocrystalline filtering silicon layer, improved membrane durability at higher gas permeability.
31 cl, 9 dwg, 2 ex
SUBSTANCE: invention is related to the field of manufacture of micromechanical devices, namely to methods of formation of scanning probe microscope probes, in particular, cantilevers consisting of console and needle. In method of cantilever manufacture that includes formation of KDB on top surface of single-crystal silicic wafer with orientation (100) of cantilever needle by method of local anisotropic etching of silicon, formation of p-n transition on top side of wafer, local electrochemical etching of wafer from the back side to p-n transition with creation of silicic membrane, formation of cantilever console from the saidmembrane by means of local anisotropic etching of membrane from both sides of plate with application of mask that protects needle and top part of console, needle of cantilever is formed prior to formation of p-n transition. Depth of n-layer amounts to doubled thickness of console, and mask for local anisotropic etching of membrane is received by method of lift-off lithography with application of bottom "sacrificial" layer and top masking layer from chemically low-activity metal.
EFFECT: obtaining of cantilever with reproduced geometric parameters of console and higher resolution of needle.
3 cl, 15 dwg
SUBSTANCE: invention relates to microstructural technologies, namely to nanotechnology, in particular, to method of obtaining fibrous carbon nanomaterials which consist from carbon nano-tubes, by method of precipitation from gas phase. Reactor is filled with inert gas and its central part is heated. Then reaction mixture containing carbon source and ferrocene catalyst source is injected, which under impact of temperature turns into vapour. Vapour is kept in hot zone by ascending inert gas flow, source of padding for precipitation of catalyst nanoparticles and growth of carbon nano-tubes being introduced into reaction mixture. As padding source used are complexes of macrocyclic polyesters with salts of metals selected from line Ca, Ba, Sr, Y, Ce, which have temperature of decomposition lower than catalyst source, and serve as continuous source of padding.
EFFECT: synthesis of carbon nano-tubes is performed continuously, which results in increase of carbon nano-tubes output.
1 dwg, 3 ex
SUBSTANCE: invention relates to nanotechnology and nanomaterials and can be used at receiving of inorganic and organic-inorganic fine-grained and nano-structured metallised materials, metal-polymers and nanocomposite. Suspension of organic-inorganic nanostructures, containing nanoparticles of noble metals, implemented in the form of poly-complex in two-phase reacting system, consisting of two volume contacting immiscible liquids. Poly-complex includes organic molecules, containing amides in amount 2 or more, and nanoparticles of noble metals. Suspension is received by means of forming of two-phase reacting system, consisting of two contacting volumetric immiscible liquids, addition in it of restorative and synthesis of nanoparticles. Additionally metallised molecules of precursors are dissolved in hydrophobic phase, reducer is added into aqueous phase, and in the capacity of ligands there are used organic molecules, into content of which there are included amides in amount 2 or more. Invention provides receiving of new nano-structured organic-inorganic polymeric complexes on the basis of polyamines, containing nanoparticles of noble metals (Pd, Au) of size up to 10 nm, which allows high specific surface area and are characterised by narrow dispersion of dimensions.
EFFECT: it is provided high density of particles packing in organic-inorganic nano-structures and high performance of transformation of initial material into nanoparticles of noble metals.
23 cl, 12 dwg, 1 ex
SUBSTANCE: invention relates to nanotechnology and can be used for effective change of physicochemical properties of formed on nanoparticles surface inorganic nature of ligand envelope. For receiving of nanoparticles solution with ligand envelope into solution of metal salt in water or organic vehicle is successively introduced stabiliser solution, consisting ligands, and solution of reducer. After it is changed charge sign of ligand envelope by means of one-sided diffusion of substance molecules, changing charge sign of ligand envelope through the semipermeable membrane, into solution of nanoparticles. Additionally it is used membrane, allowing pores size less than size of nanoparticles, but more than size of substance molecules, changing charge sign of ligand envelope. In the capacity of stabiliser it is used substance, molecules' size of which less than size of semipermeable membrane pores.
EFFECT: it is provided receiving of nanoparticles with ligand envelope with specified properties.
2 cl, 2 ex
SUBSTANCE: invention relates to production of nanodisperesed metals in a liquid phase. One provides for passage of alternating current between electrodes immersed in a liquid phase and particles of metal being dispersed introduced into the interelectrode space. Ratio of the electrode length to the width of the spacing between the electrodes is equal to 20÷200:1. The electric current voltage and frequency are maintained at the level of 1.5-5.5 kV and 0.25-0.8 MHz accordingly. Additionally an inert gas is injected into the liquid phase in the form of bubbles sized 0.1-0.5 mm. The liquid phase is agitated due to continuous circulation of the liquid phase, particles of metal being dispersed and the inert gas within a looped circuit including the interelectrode space.
EFFECT: provision for extension of the functional capabilities of the method for production of nanodispersed metals in a liquid phase, its simplification, performance enhancement and improvement of working conditions.
4 cl, 14 dwg, 2 tbl, 9 ex
FIELD: technological processes.
SUBSTANCE: invention is related to the field of metal plastic working and may be used in manufacturing of multiplane pipelines for pneumatic hydraulic systems of aggregates and machines. Module for electropulse and sphere-dynamic power plasticisation of pipeline billet metal comprises device for electropulse processing and device for power processing with sphere-dynamic impact pulses. Device for electropulse processing comprises current collectors connected to generator of electric pulses, and two faceplates. Faceplates are connected by two vertical stands with elastic elements. One of faceplates has the possibility of reciprocal displacement along vertical stands. Device for power processing has two strikers. Working surfaces of strikers are arranged along differently directed curves of logarithmic spiral of Ya.Bernoulli with different lifting angles.
EFFECT: provision of generation of regulated field of compressive stresses in metal purified from dislocations, which guarantees preservation of geometry of pipelines made of billets.
FIELD: technological processes.
SUBSTANCE: invention is related to the field of metal plastic working and may be used in manufacturing of multiplane pipelines for pneumatic hydraulic systems of aggregates and machines. Pipe billet is exposed to initial impact pulses of sphere dynamic action. Pulses are applied to diametrically installed sections of external surface of billet along curve having shape of logarithmic spiral of Ya.Bernoulli. Moreover, deformation extent is provided on every side of billet along its whole length, which is identified from the given expression. Then series of electric current pulses are applied to billet with current density in pulse Q=(1.2…2.0) 104. Duration of electric current pulses action τ=(0.3…0.4) T, where: T is duration of action at pipe billet with initial impact pulses. Then secondary impact pulses of sphere dynamic action are applied on external surface of pipe billet. Value of deformation extent from every side of pipe billet from secondary impact pulses is identified from given expression.
EFFECT: provision of generation of regulated field of compressive stresses in metal purified from dislocations, which guarantees preservation of geometry of pipelines made of billets.
2 dwg, 1 ex
SUBSTANCE: invention relates to methods of applying electroconductive nanostructurised coverings with high electroconductivity and wear-resistance. Method includes supply of powder composition with reinforcing particles from four measuring apparatuses into supersonic stream of heated gas and application of powder composition on product surface. First, from first measuring apparatus reinforcing ultra-dispersive particles of ZrO2 with fraction from 0.1 to 1.0 mcm are supplied and product surface is processed until juvenile surface is formed. Then powder composition based on Cu or Al is applied on product surface by supplying powder from four measuring apparatuses. From the first measuring apparatus reinforcing ultra-dispersive ZrO2 particles are supplied, from the second - Cu or Al powder, form the third - reinforcing nanoparticles of quasi-crystalline compound of system Al-Cu-Fe, and from the fourth measuring apparatus - reinforcing particles Y2O3. Rate of heterophase flow during application of composition based on Cu or Al is changed within the range from 450 to 750 m/sec.
EFFECT: reduction of porosity, increase of wear-resistance, adhesive and cohesive strength of covering preserving its high electroconductivity.
4 cl, 1 tbl, 1 ex
SUBSTANCE: invention is provided for nanoelectronics, analytical chemistry, biology and medicine and can be used for manufacturing of sensors, polymers and liquid crystals. Between volumes of liquid hydrocarbon composition and electrically conducting liquid it is formed boundary, on which there are actuated microplasmous discharges by means of voltage application between electrodes, located in these volumes. Using power supply with frequency 50 Hz, providing smoothly varying of preset voltage from 0 up to 4000 V, it is implemented anodic or cathodic high-voltage polarisation of boundary and high-temperature electrochemical conversion with formation of carbon-bearing nano-materials. In the capacity of liquid hydrocarbon compound can be used, for instance, benzol or octane; in the capacity of electrically conducting liquid - solution of potassium hydroxide, solutions of halogenides of alkaline metals. On boundary it can be located diaphragm, implemented of glass or from aluminium foil with oxide coating.
EFFECT: receiving the ability to implement controllable synthesis of carbon-bearing nano-materials.
8 cl, 6 dwg, 3 tbl
SUBSTANCE: invention relates to method of receiving of powder of nano-crystalline calcium hydroxyapatite. Nano-crystalline calcium hydroxyapatite is received by interaction of calcium hydroxide and solution, containing phosphate-ions, herewith suspension of calcium hydroxide is prepared directly before interaction with solution, containing phosphate-ions from solutions of calcium acetate and potassium hydroxide, herewith amount of calcium hydroxide is from 50 up to 100% in mixture of calcium-bearing components.
EFFECT: receiving of hydroxyapatite powder with particles size 30 - 50 nm.
3 dwg, 1 tbl, 1 ex
SUBSTANCE: invention relates to method of receiving of nano-crystalline hydroxyapatite. According to the invention calcium nano-crystalline hydroxyapatite is received by interaction of compound of calcium and ammonium hydro-phosphate. In the capacity of calcium compound it is used sugar lime C12H22-2nO11Can, at n, which is situated in the range from 0.5 up to 2. Particles size of the received hydroxyapatite is 30-50 nm.
EFFECT: receiving of nano-crystalline powder of calcium hydroxyapatite, which contains unaggressive biocompatible accompaniment of the reaction and that provides its usage in medicine.
3 dwg, 1 tbl, 1 ex
FIELD: carbon materials.
SUBSTANCE: weighed quantity of diamonds with average particle size 4 nm are placed into press mold and compacted into tablet. Tablet is then placed into vacuum chamber as target. The latter is evacuated and after introduction of cushion gas, target is cooled to -100оС and kept until its mass increases by a factor of 2-4. Direct voltage is then applied to electrodes of vacuum chamber and target is exposed to pulse laser emission with power providing heating of particles not higher than 900оС. Atomized target material form microfibers between electrodes. In order to reduce fragility of microfibers, vapors of nonionic-type polymer, e.g. polyvinyl alcohol, polyvinylbutyral or polyacrylamide, are added into chamber to pressure 10-2 to 10-4 gauge atm immediately after laser irradiation. Resulting microfibers have diamond structure and content of non-diamond phase therein does not exceed 6.22%.
EFFECT: increased proportion of diamond structure in product and increased its storage stability.