19 results about "Oxygen precipitation" patented technology

The invention relates to the technical field of semiconductor processing, in particular to an oxidation induced fault suppression system for a monocrystalline silicon rapid heat treatment process, comprising: an RTP reaction chamber having an outer reaction chamber and a quartz reaction chamber arranged therein; the heating unit is provided with an upper heating unit and a lower heating unit which are respectively positioned at the top and the bottom of the quartz reaction cavity; the gas path structure is provided with an upper-layer process gas pipeline and a lower-layer process gas pipeline which are connected to the interior of the quartz reaction cavity, high-purity argon is introduced into the upper layer, nitrogen-hydrogen mixed gas is injected into the lower layer, and oxygen readsorption is inhibited through gas layering; the in-situ monitoring module is arranged on the lower side of the quartz reaction cavity and is used for monitoring the crystal temperature gradient and the oxygen precipitation density.

The invention belongs to the technical field of semiconductor material processing, and particularly relates to a monocrystalline silicon preparation method for improving forward voltage drop of a power device, the power device and monocrystalline silicon, and the method comprises the following steps: when a monocrystalline silicon rod is drawn by a czochralski method, the growth crystal orientation is 1t by controlling crystal pulling parameters and cooling parameters in an equal-diameter process; 111gt, 111gt; the silicon single crystal rod, the crystal pulling parameters and the cooling parameters are configured as follows: interstitial oxygen precipitation can be inhibited to form silicon dioxide precipitation, so that the volume microdefect density in the grown silicon single crystal is lower than a preset threshold value, and the method provided by the invention inhibits the interstitial oxygen precipitation process by reasonably configuring the crystal pulling parameters and the cooling parameters, so that the yield of the silicon single crystal is improved. According to the present invention, the silicon dioxide deposition formation is reduced, such that the volume micro-defect density in the grown monocrystalline silicon is lower than the preset threshold value, and when the monocrystalline silicon is applied to the ultra-fast recovery diode product, the forward voltage drop value VF can be reduced so as to be within the range of 1.3-1.7 V so as to meet the customer requirements.

The invention relates to the technical field of new energy, in particular to a metal-water battery system capable of storing energy and asynchronously producing hydrogen and oxygen, the metal-water battery system comprises a bifunctional catalyst, an iron deposition / dissolution electrode and an acidic electrolyte, and the metal-water battery system is prepared by the following specific steps: S1, stainless steel such as 304 or 316 is subjected to molten salt electrolysis modification to prepare the bifunctional catalyst, and the bifunctional catalyst has OER and HER catalytic activity; s2, taking the modified stainless steel catalyst as a first anode, taking inert electrodes such as a copper sheet or a titanium sheet as a first cathode, and forming a first electrolysis system with an acidic ferrous sulfate solution; and S3, electrolysis is conducted through the first electrolysis system, oxygen evolution reaction is conducted on the first anode, and metal iron is deposited on the first cathode. According to the metal-water battery system considering energy storage and asynchronous production of hydrogen and oxygen, time-space separation of deposition / dissolution of iron and hydrogen-oxygen precipitation is regulated and controlled through the bifunctional catalyst, and safe energy storage and step-by-step production of hydrogen energy / oxygen are achieved; the method is suitable for renewable energy storage, hydrogen energy preparation and distributed energy supply scenes.

The present application relates to oxygen precipitation and oxygen reduction electrocatalyst technical field, especially an accordion type carbon supported single atom-cluster catalyst and preparation method and application. The present application first synthesizes a kind of accordion type coordination polymer containing zinc and iron series metal (such as iron, cobalt, nickel), then it is etched using potassium ferricyanide or potassium cobalticyanide;Finally, pyrolysis is carried out under nitrogen atmosphere, forming an accordion type carbon supported single atom-cluster catalyst. The new catalyst has a unique accordion type layered structure, higher specific surface area, more active sites, and the main skeleton nitrogen-doped carbon of the catalyst has good conductivity, which can accelerate the mass transfer and charge transfer process of electrocatalytic reaction. The present application belongs to a new type of bifunctional catalyst, which can catalyze oxygen reduction reaction and drive oxygen precipitation reaction, meet the needs of rechargeable zinc-air battery, and show potential application prospect to replace commercialized noble metal catalyst.

The invention provides an amorphous substance coated positive electrode active material as well as a preparation method and application thereof. In the invention, the amorphous substance is selected from one or more of transition metal silicide, boride, phosphide, sulfide, selenide, carbide, amorphous carbon or amorphous silicon materials. The amorphous substance coating in the invention can form a compact self-healing passivation layer at the interface of the positive electrode material, not only can inhibit oxygen precipitation under high voltage in dynamics, but also can be combined with Li alkali metal to become a mixed conductor of ions and electrons, so that the conduction performance of the electrons and lithium ions is improved, and the interface impedance is reduced. Meanwhile, the surface of the positive electrode material can be uniformly coated by a special coating mode of the amorphous substance, so that side reaction between the positive electrode material and electrolyte is effectively inhibited, a solid electrolyte membrane on the surface of the positive electrode material is stabilized, formation of microcracks in the material is reduced, and the cycling stability is improved.

Methods for detecting oxygen precipitation induced defects during a polishing sequence. The methods are suited for detecting oxygen precipitates in heavily doped boron single crystal silicon wafers or in lightly doped wafers that are COP-free. The methods may involve inspecting a silicon wafer for LLS defects after a thermal anneal followed by a polishing sequence.

The application discloses a chain type pretreatment and efficiency improving equipment for TOPCon cell raw material silicon wafers. The equipment has a heating cavity with a silicon wafer conveying roller, and a temperature sensor and gas inlet and outlet pipelines are arranged in the heating cavity; heating, gas circulation and alarm functions of a central computer control device are provided. The core of the equipment is that the high temperature set in the furnace cavity can be reached, and the stability and uniformity of the temperature in the cavity are ensured; through the high temperature above 1100 DEG C and the oxygen atmosphere, the oxygen precipitation and vacancy defects in the photovoltaic N-type silicon are ablated and repaired, the recombination center in the material body is reduced, the bulk lifetime of the silicon is increased, and thus the cell efficiency is improved; the time required for pretreatment is greatly shortened, and the equipment is favorable for large-scale industrial application.

Methods for detecting oxygen precipitation induced defects during a polishing sequence. The methods are suited for detecting oxygen precipitates in heavily doped boron single crystal silicon wafers or in lightly doped wafers that are COP-free. The methods may involve inspecting a silicon wafer for LLS defects after a thermal anneal followed by a polishing sequence.

The invention provides a heating device, a single crystal furnace, a method for improving oxygen precipitation in monocrystalline silicon and monocrystalline silicon. The heating device comprises a plurality of heating pieces arranged around the monocrystalline silicon at intervals, the tops of the heating pieces are connected through a first connecting part, and the bottoms of the heating pieces are connected through a second connecting part; the first connecting part and the second connecting part are both of an annular structure; the heating sheet comprises a first sub-heating part, a second sub-heating part and a third sub-heating part which are sequentially connected from top to bottom, the first sub-heating part is connected with the first connecting part, the third sub-heating part is connected with the second connecting part, and the condition that S1 < 1gt > is met; s2gt; and S3. The heating device is used for heating the monocrystalline silicon in the growth process of the monocrystalline silicon rod, the thermal history of the monocrystalline silicon can be improved, so that primary oxygen precipitation in the monocrystalline silicon is reduced, meanwhile, the monocrystalline silicon can be uniformly heated in the single crystal furnace by controlling the heat transfer area of the heating piece from top to bottom to be gradually reduced, and the quality of the monocrystalline silicon is improved. And the radial uniformity of oxygen precipitation is improved.

The invention relates to the technical field of semiconductor materials, in particular to a heavily-doped silicon single crystal oxygen precipitation detection method which comprises the following steps: S1, pickling a complete silicon wafer; s2, spraying the atomized transition metal salt solution on the surface of the silicon wafer; s3, placing the silicon wafer in a nitrogen atmosphere of 750-900 DEG C, and keeping the temperature constant for 30-60 minutes; s4, cooling the silicon wafer to room temperature at a cooling rate of 10-20 DEG C / s; s5, removing an interference layer on the surface of the silicon wafer; s6, observing the metal decoration pattern on the surface of the silicon wafer to judge the oxygen precipitation concentration; thus, through cooperative control of the temperature and the cooling rate, the metal ions are selectively deposited only at the oxygen precipitation and the induced defects of the oxygen precipitation, so that the concentration of the oxygen precipitation is accurately and reliably revealed; meanwhile, the oxygen precipitation concentration is measured by performing metal decoration on the surface of the complete silicon wafer, so that the influence of artificial damage caused by cutting the sample on the detection result can be avoided, and the accuracy of the oxygen precipitation concentration detection result is remarkably improved.

The invention discloses a device and method for producing hydrogen through wastewater treatment, and belongs to the technical field of wastewater treatment. The device comprises a wastewater pretreatment mechanism, the wastewater pretreatment mechanism comprises a mounting bottom plate, a precipitation bin is fixedly connected to the top of the mounting bottom plate, and a water inlet pipe is arranged on one side of the upper end of the precipitation bin. The invention aims to solve the problems that in the electrolysis process in the prior art, bubbles are attached to the surface of an electrode plate to form a gas film, so that the mass transfer resistance is remarkably increased, and the electrolysis efficiency is reduced, and achieves the technical effects that the two sides of the bipolar electrode are respectively subjected to hydrogen-oxygen precipitation reaction; by combining the bubble guiding micro groove and the auxiliary defoaming design of the vibration motor, the bubble separation speed is remarkably increased, the electrolysis voltage is lower, the hydrogen production energy consumption is reduced, hydrogen and oxygen are collected through the independent cavity and the flow channel respectively, the guiding effect of the micro groove is matched, the gas cross contamination rate is lower, the hydrogen purity is higher, and the device is more convenient to use.

The application relates to the technical field of semiconductor material manufacturing, and discloses an N-type monocrystalline silicon wafer diffusion impurity absorption optimization method, which comprises the following steps: removing surface contaminants and tiny defects by pretreating an N-type monocrystalline silicon wafer; forming an impurity absorption layer on at least one surface of the pretreated N-type monocrystalline silicon wafer; performing diffusion annealing treatment on the N-type monocrystalline silicon wafer with the formed impurity absorption layer, and removing the impurity absorption layer material on the N-type monocrystalline silicon wafer after the diffusion annealing treatment; and completing the N-type monocrystalline silicon wafer diffusion impurity absorption optimization work. The impurity absorption layer formed on the surface of the silicon wafer can effectively capture and fix heavy metal impurities and defects, such as oxygen precipitation and metal precipitation, which may be generated in the subsequent process of the silicon wafer, so as to prevent the impurities and defects from causing adverse effects on the performance of the silicon wafer. The diffusion annealing treatment further promotes the diffusion of the impurities and the impurity absorption capacity of the impurity absorption layer, and ensures the effective removal of the impurities.

The application discloses doped tricobalt tetraoxide and a preparation method and application thereof. The doped tricobalt tetraoxide is doped with anions or simultaneously doped with metal cations and anions. The doped tricobalt tetraoxide is prepared by introducing anions and doping, and when metal cations are further introduced, the metal cations and the doped anions play a synergistic doping effect. The anions and the metal cations are uniformly doped in lithium cobaltate prepared by taking the doped tricobalt tetraoxide as a precursor, the structure stability of the lithium cobaltate in a charging and discharging process is improved on the basis of effectively reducing oxygen precipitation of the lithium cobaltate, the cycle stability of the lithium cobaltate at high voltage is effectively improved, and the preparation method of the doped tricobalt tetraoxide can ensure that the structure and electrochemical performance of the prepared doped tricobalt tetraoxide are stable and the efficiency is high.

The application discloses a fast-charging layered lithium-rich positive electrode material and a preparation method and application thereof, and is characterized in that the preparation method of the fast-charging layered lithium-rich positive electrode material is a specific Ti element doping modification Li2RuO3 preparation method, Ti-O strong bonds are used to play a role in stabilizing a lattice structure and inhibiting oxygen precipitation, and more importantly, through accurate control of a doping process, optimization and activation of a lithium ion two-dimensional diffusion channel are realized, a lithium ion migration energy barrier is significantly reduced, and thus a kinetic obstacle of fast charging is essentially solved. The prepared material shows a charge capacity retention rate far higher than that of a conventional modified Li2RuO3 material under a 10C (6 minutes) super-high rate charging condition. While realizing 10C fast charging, the material still maintains a high reversible specific capacity, and shows excellent capacity retention rate and structural integrity in a long-term high-rate cycle test, and overcomes the difficulty that fast charging usually accelerates material degradation.

A silicon wafer for epitaxial growth including a silicon single crystal, wherein the silicon single crystal is produced by a Czochralski method, an entire silicon single crystal is an N (Neutral) region so as not to contain a void and a dislocation cluster, size and density of oxygen precipitation nuclei are adjusted, and the oxygen precipitation nuclei with the size of 18 nm or more in the silicon wafer have the density of less than 5×107 / cm3. This provides the silicon wafer for epitaxial growth with inhibited defects and having extremely good surface layer quality.

The invention relates to a copper-based electrode and preparation and application thereof. The preparation method of the electrode comprises the following steps: pretreating the substrate, performing electrochemical etching reconstruction on the copper substrate through a constant voltage method under the condition of not adding an additional Cu source, growing a copper-cobalt transition metal oxide and boride catalyst, and performing high-temperature roasting to prepare the copper-based double-effect electrode. The structure shows excellent oxygen evolution and hydrogen evolution activity and stability in an alkaline medium. The (integrated) electrode prepared by the method does not depend on a current collector and an additional binder, so that the preparation process is simplified, and the cost is reduced. The electrode can be used for a water electrolysis hydrogen evolution electrode, a water electrolysis oxygen evolution electrode, a seawater electrolysis hydrogen evolution electrode, a seawater electrolysis oxygen evolution electrode, a metal air battery charging cathode and anode or an electrode in fuel cell reaction under an energy storage condition.

The present application relates to a kind of copper-based electrode and its preparation and application.The electrode preparation method includes: the pretreatment of substrate, by constant voltage method to copper substrate electrochemical etching reconfiguration without additional Cu source, copper cobalt transition metal oxide, boride catalyst growth, high-temperature calcination, and copper-based double-effect electrode is prepared.This structure shows excellent oxygen precipitation and hydrogen precipitation activity and stability in alkaline medium.The (integrated) electrode prepared in the application does not need to rely on current collector and additional binder, simplifies the preparation process and reduces the cost.The electrode can be used for electrolytic water hydrogen evolution electrode, electrolytic water oxygen evolution electrode, electrolytic seawater hydrogen evolution electrode, electrolytic seawater oxygen evolution electrode, metal-air battery charging cathode and anode or electrode in fuel cell reaction under energy storage conditions.

The invention relates to a surface-reconstructed lithium-rich manganese-based oxide positive electrode material and a preparation method thereof. The method comprises the following steps: (1) dispersing lithium-rich manganese-based oxide powder in a heteropolyacid solution, and fully mixing, infiltrating and drying to obtain heteropolyacid-coated lithium-rich manganese-based oxide; the heteropoly acid is an inducer for surface reconstruction of the lithium-rich manganese-based oxide; and (2) carrying out heat treatment on the heteropolyacid-coated lithium-rich manganese-based oxide to induce a surface reaction so as to obtain the surface-reconstructed lithium-rich manganese-based oxide positive electrode material. According to the method, in-situ reconstruction is carried out on the surface of the lithium-rich manganese-based oxide to obtain the disordered rock salt phase heterostructure layer, and the reconstructed layer not only inhibits oxygen precipitation and stabilizes the structure of the material, but also provides rapid lithium ion conduction, so that the charge-discharge cycle performance and the rate capability of the lithium-rich manganese-based oxide are greatly improved. In addition, the method is simple in process and low in cost, and has a large-scale application prospect.

The invention provides a vanadium oxide physical vapor deposition method. The method comprises the following steps: sputtering a vanadium oxide film; performing high-pressure or ultrahigh-pressure annealing; and performing low-temperature vacuum secondary annealing. According to the method, high-pressure or ultrahigh-pressure oxygen atmosphere annealing is adopted, oxygen precipitation, caused by high-temperature annealing, of the vanadium oxide thin film is inhibited through high-concentration oxygen, atom arrangement of the thin film tends to be flat, oxygen hole sites and defects in the thin film are repaired, and therefore thin film component distribution is improved; and removing residual oxygen atoms in the thin film through low-temperature vacuum secondary annealing. The TCR performance of the vanadium oxide film prepared by the method is excellent, and the TCR at the temperature of 25 DEG C reaches up to-2.8% or above.