13 results about "Carbon contamination" patented technology

The application belongs to the technical field of rare earth metallurgy, and discloses a method for preparing rare earth metal by electrolyzing molten salt. The method comprises the following steps: taking rare earth oxide as electrolytic raw material, and performing electrolysis in molten salt electrolyte under a protective atmosphere; and collecting the deposit after electrolysis, so that the rare earth metal is obtained. Through the synergistic effect of multi-dimensional process, the application successfully constructs an efficient, green and stable rare earth metal electrolysis preparation system. The system completely eliminates carbon pollution, significantly improves the stability of the electrolysis process and the quality of the product, realizes efficient and stable preparation of high-purity rare earth metal, and can meet the stringent requirements of high-end electronics, aerospace, high-performance permanent magnet materials and other fields for ultra-high-purity rare earth products.

The invention discloses a carbon dioxide pollution resistant filtrate reducer for water-based drilling fluid and a preparation method thereof, and belongs to the technical field of filtrate reducers for water-based drilling fluid. The preparation method comprises the following steps: sequentially dissolving monomers N 'N-dimethylacrylamide, sodium p-styrenesulfonate, dimethyl diallyl ammonium chloride, N-vinyl pyrrolidone and 2-acrylamide-2-methylpropanesulfonic acid in a molar ratio of 5: (3-8): (1-5): (0-4): (1-6) in a solvent, adding an alkali solution to adjust the pH value, heating, adding an initiator, drying, and crushing to obtain the filtrate reducer. The filtrate reducer for the water-based drilling fluid has strong competitive adsorption capacity with carbonate and bicarbonate, can improve the performance of the drilling fluid, increase the carbon dioxide containing threshold value and reduce the risk that the filtration performance is out of control after the drilling fluid is polluted by carbon dioxide, and is suitable for improving the formula of the filtrate reducer for the water-based drilling fluid.

A method for removing carbon contamination from a silicon carbide chip includes: providing a substrate having opposing first and second surfaces; forming a device layer on the first surface of the substrate, the device layer having a source doped region; forming an interlayer dielectric layer on the source doped region; etching the interlayer dielectric layer to expose the surface of the source doped region, forming a contact hole; forming a first metal layer at the bottom of the contact hole; heat-treating the first metal layer and the source doped region to form a first ohmic contact layer and a first carbon contamination layer on the surface of the first ohmic contact layer; and performing a plasma gas cleaning operation to remove the first carbon contamination layer. Since the plasma gas cleaning operation is a dry removal method, specifically involving low-energy ion bombardment to remove the first carbon contamination layer, it can remove the first carbon contamination layer while avoiding damage to the first ohmic contact layer at the bottom of the first carbon contamination layer and the surface of the source doped region, thereby improving the electrical performance and reliability of the silicon carbide chip.

The invention relates to the technical field of environmental pollution statistics and prediction, in particular to a carbon pollution fusion list mapping method, which dynamically simulates the activity level based on future resident energy consumption, industrial energy consumption and industrial process emission, and realizes a prediction list with consistent caliber. By constructing a carbon and pollutant fusion list mapping system, the emission factor construction and fusion list generation capability is provided for a carbon-pollutant collaborative emission reduction research scene. The method supports the mapping and dynamic prediction of a multi-source emission list, can output a long-term emission sequence on a provincial scale, achieves the dynamic coupling simulation of the whole process of energy supply and demand-emission-pollution-health, and carries out the prediction of a future emission list.

The invention discloses a directional controllable growth method of high-purity polycrystalline silicon, which relates to the technical field of material science and engineering, and comprises the following steps: realizing impurity atomic-scale control and non-contact smelting through a four-order synergistic process, performing electromagnetic suspension melting on industrial silicon materials in an inert coating crucible (1420-1450 DEG C, less than or equal to), separating melt from the inner wall of the crucible, and thoroughly blocking an oxygen-carbon pollution source; plasma targeted impurity removal is conducted, specifically, pulse plasma beams (50-200 W / cm, 10-30 min) with the ratio of 4: 1 are adopted for bombarding the surface of the melt, and boron and phosphorus impurities are removed through in-situ gasification; magnetic field coupling directional solidification is conducted, the axial temperature gradient is controlled to be 30-50 DEG C / cm, the solidification rate is controlled to be 0.5-2 cm / h, a transverse alternating magnetic field (0.1-0.5 T, 5-20 Hz) is overlaid to inhibit dendritic crystal deflection, and impurities are driven to be enriched towards the top; and 10-15% of an enrichment layer at the top is cut off, so that a high-purity silicon ingot with oxygen less than or equal to 0.1 ppm, carbon less than or equal to 0.1 ppm and boron phosphorus less than or equal to 0.05 ppb is obtained, and the standard of a 3nm chip substrate is met.

The application provides a drilling fluid anti-carbon dioxide pollution diluent and a preparation method and application thereof. The drilling fluid anti-carbon dioxide pollution diluent is prepared from the following raw materials in parts by mass: 10-20 parts of acrylic acid (AA), 5-15 parts of sodium p-styrenesulfonate (SSS), 1-5 parts of N-vinylpyrrolidone (NVP), 45-55 parts of isoamyl alcohol polyoxyethylene ether, 0.01-0.1 parts of an initiator, and 100-140 parts of water. The diluent can solve the problems of thickening of the drilling fluid, increase of the viscosity and shear force, and increase of the filtration loss after CO2 pollution, and is applied to the CO2-polluted drilling fluid, so that the viscosity and shear force of the CO2-polluted drilling fluid can be effectively reduced, and the filtration loss of the drilling fluid can be reduced.

This invention discloses a SiC substrate MOCVD gallium oxide epitaxial wafer, belonging to the field of wide-bandgap semiconductor epitaxial material preparation technology. The epitaxial wafer comprises, from bottom to top, a silicon carbide substrate, a β-Ga2O3 carbon getter layer, and a β-Ga2O3 drift layer. The carbon concentration ratio of the β-Ga2O3 carbon getter layer to the β-Ga2O3 drift layer is not less than 100, forming a decreasing carbon concentration gradient. The β-Ga2O3 drift layer contains periodically distributed annealing repair interfaces. The preparation method employs a precursor spatiotemporal separation alternating gas supply mode to grow the β-Ga2O3 drift layer, with periodic insertion of in-situ flash annealing steps. A three-stage carbon purification mechanism synergistically removes carbon from three stages: carbon source generation, defect complex formation, and cumulative stabilization, solving the technical bottleneck of uncontrollable carrier compensation ratio caused by organometallic precursor carbon contamination during MOCVD growth of ultra-thick drift layers.

The invention relates to the technical field of semiconductor wafers, in particular to a preparation method of a semiconductor graphical epitaxial thin film, an embedded electrode structure and application, and the method comprises the following steps: S1, carrying out the pretreatment of a substrate layer, and carrying out the low-temperature deposition of a high-temperature-resistant hard mask layer on the surface of the pretreated substrate layer; s2, performing segmented etching treatment on the deposited high-temperature-resistant hard mask layer and part of the substrate layer according to a photoetching pattern, and removing the photoresist after etching treatment to obtain a first substrate; s3, the first substrate is placed in a PLD cavity, a bottom electrode thin film layer is epitaxially deposited on the etching face of the first substrate, the thickness of the bottom electrode thin film layer is the same as the etched depth of the substrate layer, and a second substrate is obtained; and S4, performing wet etching on the second substrate until the high-temperature-resistant hard mask layer is completely removed, and performing post-processing to obtain the embedded electrode structure. According to the technical scheme, the problems of high-temperature failure, cavity carbon pollution, pattern collapse, surface roughness and the like of traditional optical cement are solved.

The utility model provides a guide cylinder assembly and a single crystal furnace. The guide cylinder assembly comprises a guide cylinder body, an inner sleeve body and a positioning pin, the guide cylinder body is provided with an axially through cylinder channel; the inner sleeve body is arranged in the barrel channel and is provided with a hollow space through which a silicon rod can penetrate, and a pin hole is formed in the inner sleeve body in the wall thickness direction; the positioning pin is connected with the pin hole in a penetrating mode, and the bottom end of the positioning pin is a reference point for measuring the melting gap. By means of the arrangement, the guide cylinder body serves as an existing guide cylinder, hole opening design is not needed, the inner sleeve body is additionally arranged in the guide cylinder body, the inner sleeve body does not have the function of the guide cylinder and can be punched at will, and therefore an installation position is provided for the positioning pin, and the positioning pin is installed at the position outside the guide cylinder body. The loss of the filler in the guide cylinder body is not accelerated, the carbon pollution risk caused by tapping is avoided, and the problems that the arrangement mode of the positioning pin for detecting the melt gap in the single crystal furnace in the prior art is not beneficial to protecting the interior of the guide cylinder and the carbon pollution risk is increased are solved.

The invention belongs to the technical field of rare earth metallurgy, and discloses a method for preparing rare earth metal by electrolyzing molten salt. The method for preparing the rare earth metal through electrolysis of the molten salt comprises the following steps that under the protective atmosphere, a rare earth oxide serves as an electrolysis raw material, electrolysis is conducted in molten salt electrolyte, sediment is collected after electrolysis is finished, and the rare earth metal is obtained. The efficient, green and stable rare earth metal electrolysis preparation system is successfully constructed through the synergistic effect of a multi-dimensional technology, the stability of the electrolysis process and the product quality are remarkably improved while carbon pollution is thoroughly eradicated, efficient and stable preparation of high-purity rare earth metal is achieved, and the method is suitable for industrial production. And the harsh requirements on ultra-pure rare earth products in the fields of high-end electronics, aerospace, high-performance permanent magnet materials and the like can be met.

A high-temperature response composite material for synergistic regulation of coal pile fire resistance and heat value release, and a preparation method and application thereof. The material is composed of modified inorganic particle fillers and composite high heat value carriers. The modified inorganic particle fillers include organic modified SiO2 particles and MnFe2O4 nanoparticles grafted with hydroxyl functional groups. The composite high heat value carrier is composed of polyether, polydimethylsiloxane and white oil high heat value oil phase. After treatment, the components form a uniform dispersion, stable emulsion composite system, with good seepage perfusion performance and environmental adaptability. At room temperature, the initial oxidation rate of coal is reduced by blocking the diffusion path of water and oxygen, realizing efficient fire resistance. At high temperature, the cracking and oxidation process of coal and organic carriers is accelerated by catalysis, inhibiting oil phase agglomeration and carbonization coking problems, significantly improving the burnout rate and clean combustion performance. The material system has multiple advantages such as room temperature fire resistance, high temperature combustion support and no residual carbon pollution.

This invention discloses a method for preparing magnesium-aluminate spinel transparent ceramics by hot-pressing sintering based on mold isolation technology, belonging to the field of transparent ceramics technology. The method involves setting an isolation layer between a graphite mold and a ceramic blank; wherein the isolation layer includes a graphite paper substrate and a homogeneous isolation layer disposed on one side of the graphite paper substrate, the homogeneous isolation layer being made of the same material as the ceramic blank. The isolation layer of this invention effectively blocks the diffusion of carbon-active substances released from the graphite matrix under high temperature and pressure into the ceramic blank, thereby significantly reducing the penetration and residue of carbon impurities inside the ceramic. This method achieves physical isolation by addressing the contamination propagation path, effectively suppressing carbon contamination in transparent ceramics at a lower cost without significantly altering the existing main process, and helps improve the optical uniformity, transmittance, and long-term reliability of the product.