195 results about "Electrochemical etching" patented technology

The invention discloses an SERS (Surface Enhanced Raman Scattering) substrate with a needle-like diagram nanostructure and a preparation method of the SERS substrate, and belongs to the field of nanotechnology and detection. The preparation method of the needle-like Turing nano-structure SERS substrate comprises the following steps: by taking a silver needle as a carrier, carrying out electrochemical etching on the surface of the silver needle to induce to form a Turing nano-structure with fractal topological characteristics, and then inducing to conformally grow a layer of zeolite imidazole framework-8 material as a shell layer by utilizing the nano curvature characteristics of the fractal structure, so as to prepare the needle-like Turing nano-structure SERS substrate. And a composite SERS enhanced platform with an electromagnetic field hot spot aggregation effect and a molecular screening and enriching capability is constructed. The platform has the advantages of high structural uniformity, expandability in manufacturing, synergy of signal enhancement and molecular recognition and the like, remarkably improves the detection sensitivity and the signal reproducibility, and is suitable for trace analysis in a complex sample system, such as related application in the fields of food safety, environmental pollution monitoring, biomedicine and the like.

Fabrication methods and structures for forming integrated circuit (IC) porous semiconductor (π-Semi) isolation structures such as shallow trench isolation (STI) and / or deep trench isolation (DTI) structures. The methods speed up IC front-end-of-line processing and decrease the cost of IC fabrication. In general, exposed portions of a semiconductor layer are subjected to an electrochemical etching to form π-Semi isolation structures; in essence, the in situ semiconductor is restructured to π-Semi. The characteristics of π-Semi, particularly mesoporous π-Semi and microporous π-Semi, include good electrical insulation as well as hole trapping capability. Accordingly, π-Semi used for STI and / or DTI structures provides excellent electrical isolation. A first embodiment comprises a “pre-FET”π-Semi isolation structure, fabricated before formation of gate, drain, and source structures or regions of a field-effect transistor (FET). A second embodiment comprises a “post-FET”π-Semi isolation structure, fabricated after formation of gate, drain, and source structures or regions of a FET.

The invention provides a laser polishing device combining gas protection and substrate heat dissipation and a using method. The device comprises a focus lens (1), a laser beam (2), a to-be-polished sample piece (3), a gas nozzle (4), a gas pipe (5), a high-pressure gas cylinder (6), a dust collector (7), a cooling liquid level (8), a metal substrate (9), an objective table (10), a water tank (11) and a laser (12). The invention further relates to a using method of the device. A micro-nano coarse structure is formed on the surface of the metal substrate through chemical etching, electrochemical etching or laser etching and the like, then a hydrophilic oxide layer is introduced through oxidation treatment or plasma treatment, and the super-hydrophilic performance of the metal substrate is further enhanced. The device has excellent liquid cooling capacity, gas protection performance and oxidation resistance, heat can be efficiently conducted and dissipated in the laser polishing process, the temperature uniformity of the surface of a sample is ensured, and overheating and oxidation phenomena are prevented.

The invention belongs to the technical field of preparation of high-quality metallic nickel connecting strips for new energy batteries, and provides a preparation process for optimizing residual stress of a metallic nickel stamping connecting sheet for a new energy battery, which specifically comprises the steps of material selection, striping, continuous die stamping, inert atmosphere protection annealing, and residual stress detection and control. The range of corners and chamfers of a stamping die adopted in the progressive die stamping is 0.2 mm-1 mm, and the fit dimensional tolerance of a female die and a male die of the stamping die is controlled to be + / -0.05 mm; and the stamping surface in contact with the metal nickel strip is processed by adopting an electrochemical corrosion milling method, the roughness Ra of the stamping surface is less than 0.4 mu m, and the hardness HRC is more than or equal to 55. The metal nickel connecting strip prepared through the method is low in residual stress and small in size deformation after being used, the service life of the metal nickel connecting strip is prolonged, safety and reliability of the metal nickel connecting strip are improved, and the application prospect is wide.

The invention provides an electrochemical etching preparation method of a perforated battery copper foil, which comprises the following steps: firstly, pretreating the copper foil, then performing asymmetric bidirectional pulse etching in a specific electrolyte system by taking the copper foil as an anode and a platinum sheet as a cathode, and gradually decreasing the pulse interval time in a gradient manner in the etching process; and after etching is completed, immediately transferring into an ammonia water solution containing a sulfonated modified calixarene supramolecular corrosion inhibitor to stop the reaction, and drying and annealing to obtain the sulfonated modified calixarene supramolecular corrosion inhibitor. By dynamically regulating and controlling the pulse interval time and cooperating with the electrolyte with specific components and the efficient supramolecular corrosion inhibitor, the uniformity and controllability of the etching process are remarkably improved, and the problems that in the prior art, hole distribution is not uniform, excessive etching is likely to happen, the hole shape is irregular, and efficiency is low are solved; the prepared copper foil has the characteristics of uniform and consistent pore structure, smooth pore wall and excellent mechanical property and conductivity, and the application performance and reliability of the copper foil in a high-end lithium ion battery current collector are greatly improved.

The invention relates to a preparation method of a multilayer alloy net electrode for hydrogen production by alkaline electrolysis of water and the multilayer alloy net electrode, and the preparation method comprises the following steps: firstly, selecting an alloy electrode net material, then etching the alloy electrode net, and carrying out electrochemical etching by taking the alloy electrode net as an anode and an inert electrode as a cathode and using 0.5-5M acid liquor to prepare the multilayer alloy net electrode. The preparation method comprises the following steps: sequentially overlapping a first layer of pure nickel net with the mesh number of 80-200 and a second layer of etched alloy electrode net with the mesh number of 40-80 and a third layer of etched alloy electrode net with the mesh number of 20-40, carrying out vacuum sintering at 800-1400 DEG C for 2-5 hours, and finally stirring and drying in a polyethyleneimine aqueous solution. Compared with the prior art, the obtained electrode has the advantages of being low in cost, high in catalytic activity, fast in bubble removal, high in durability and stability and the like, effectively solves many problems of an existing alkaline water hydrogen production electrode, has a wide application prospect in the field of alkaline water electrolysis hydrogen production, can remarkably improve the water electrolysis efficiency and is beneficial to large-scale industrial production.

The invention provides an aluminum foil and a preparation method thereof, the preparation method comprises the following steps: the aluminum foil is subjected to electrochemical corrosion in a mixed acid solution, the half cycle of alternating current adopted by the electrochemical corrosion comprises a plurality of wave crests, and the mixed acid solution comprises at least one of nitric acid and phosphoric acid; passivating the aluminum foil; washing the aluminum foil with water; and the steps of electrochemical corrosion, passivation treatment and water washing are repeated until the aluminum foil reaches the preset corrosion amount. The nitric acid can improve the overall corrosion amount, reduce the surface corrosion of the aluminum foil and promote the longitudinal development of corrosion. Phosphate radicals and aluminum ions can form a complex, so that the concentration of free Al < 3 + > in a hole etching area is reduced, corrosion reaction balance is pushed to move rightwards, and further corrosion is promoted.

The invention relates to a controllable electrochemical etching strategy based on solubility product difference, in particular to a preparation method of a barium sulfate modified NiCo-LDH aqueous alkaline zinc battery positive electrode material, which comprises the following steps: firstly, dissolving 1, 4-phthalic acid and sodium hydroxide in a molar ratio of 1: 2 in water to obtain a solution A; dissolving barium nitrate pentahydrate, cobalt nitrate hexahydrate, nickel nitrate hexahydrate and ammonium fluoride in water according to a molar ratio of (0-1.5): 1: 4: 10 to obtain a solution B; the preparation method comprises the following steps: fully mixing the solutions, transferring the mixed solution into an autoclave containing foamed nickel (NF), and carrying out solvothermal reaction to obtain a tri-metal Co / Ni / Ba-MOF precursor (CNBx-BDC); cNBx-BDC is used as a working electrode, a platinum wire is used as a counter electrode, Hg / HgO is used as a reference electrode, 5-6M potassium hydroxide and 0.05-0.06 M sodium sulfate are used as electrolyte, a three-electrode system and a cyclic voltammetry method are adopted, electrochemical etching is carried out at the scanning rate of 20-30mV s <-1 > under the voltage range of 0-0.5 V, and the barium sulfate nanodot functionalized Co / Ni / Ba-LDH electrode (BS (at) CN-LDH) is obtained after six times of circulation. The unique porous structure can provide more electrochemical active sites and enhance electrolyte infiltration capacity, and the constructed heterostructure forms a strong built-in electric field, accelerates charge transfer, reduces ion diffusion energy barriers and improves energy utilization efficiency.

A surface treatment method for a metal composite body, comprising: providing a metal composite body, comprising a first metal part and a second metal part integrated into one body; roughening the exposed surface of the first metal part of the metal composite body by using an etching solution; anodizing the roughened metal composite body to form an oxide film on the surface of the second metal part; and etching the anodized first metal part of the metal composite body by electrochemical etching to form a plurality of micropores. The metal composite body is firstly corroded to roughen the surface of the first metal part, and then the metal composite body is anodized to form an aluminum oxide film on the surface of the second metal part of the metal composite body, and then electrochemical etching is performed to etch micropores of a desired size on the surface of the first metal part.

The invention provides a preparation method of a nano-selenium fertilizer prepared by an electric etching method and agricultural application. The preparation method of the nano-selenium fertilizer prepared by the electric etching method comprises the following steps: S1, preparing a selenium-containing precursor solution; s2, connecting a graphite rod with a direct-current power supply anode and immersing into the solution, and connecting another conductive substance with a direct-current power supply cathode; s3, applying direct-current voltage for etching, and performing centrifugation and concentration treatment on the electrolyte to obtain the nano-selenium fertilizer; the nano-selenium fertilizer is added into a hydroponic nutrient solution, the problem of large-scale production of the nano-selenium fertilizer is solved with a low-cost and green process through an electrochemical etching in-situ synthesis path, the bottleneck of traditional selenium fertilizer absorption efficiency is broken through depending on a selenium-carbon quantum dot composite structure, and an efficient solution is provided for agricultural quality and yield improvement.

The invention relates to the technical field of field emission cathodes, in particular to an Au nanoparticle modified 4H-SiC nanowire field emission cathode and a preparation method thereof. The method comprises the following steps: (1) performing electrochemical etching on a 4H-SiC wafer, processing a bamboo-like 4H-SiC nanowire array on the surface of the 4H-SiC wafer, and stripping the 4H-SiC nanowire array from the 4H-SiC wafer; (2) carrying out magnetron sputtering on Au nanoparticles on the surface of the 4H-SiC nanowire array obtained in the step (1); and (3) annealing treatment is carried out on the 4H-SiC nanowire array with the Au nanoparticles, the annealing temperature is 200-400 DEG C, the heat preservation time is 50-70 min, and the Au nanoparticle modified 4H-SiC nanowire field emission cathode is obtained. The bamboo-like 4H-SiC nanowire attached with Au nanoparticles is annealed, and the obtained field emission cathode is low in turn-on electric field and high in electron emission stability.

The invention provides an electrolyte composition, an electrochemical in-situ etching method of non-metallic inclusions for heavy rail steel and application of the electrochemical in-situ etching method. The electrolyte composition comprises the following components in parts by weight: 1.6 to 2.3 parts of lithium chloride, 10 to 13.5 parts of acetylacetone, 45 to 84 parts of methanol and 2 to 43 parts of a reagent A, the reagent A is a mixed aqueous solution of ethylenediamine tetraacetic acid and sodium citrate. The lithium chloride, the acetylacetone, the methanol and the reagent A in specific parts are matched for use, the obtained electrolyte composition is used for in-situ electrochemical etching of the heavy rail steel, and three-dimensional in-situ etching of the non-metallic inclusions in the heavy rail steel can be successfully achieved. The in-situ information of the non-metallic inclusions in the hypereutectoid heavy rail steel is reserved, and the three-dimensional morphology of the non-metallic inclusions can be presented more comprehensively.

The invention relates to the technical field of batteries, in particular to an ultra-thin copper foil, a preparation method thereof and a battery. The preparation method comprises the following steps: providing an initial copper foil, fixing the initial copper foil on an anode plate, placing the initial copper foil and a cathode plate in an electrolyte together, electrifying and carrying out electrochemical etching, so that the thickness of the initial copper foil fixed on the anode plate is reduced, and the ultra-thin copper foil is obtained. According to the method, the thick initial copper foil is used as the anode, the electrochemical etching method is used for preparing the ultra-thin copper foil, the problems that when the ultra-thin copper foil is produced in the prior art, the copper foil with the specific thickness is selected as a carrier, and stripping is needed again, so that the process is tedious, and the cost is high are solved, and a new thought is provided for development of the ultra-thin copper foil. Meanwhile, no specific requirement on the copper foil of the anode exists, that is, the copper foil at the anode is easy to obtain, and the preparation cost of the ultrathin copper foil is effectively reduced.

The invention discloses a preparation method of a metal surface micro-pattern texture, and belongs to the technical field of metal materials and machining thereof. The method comprises the following steps: S1, depositing a metal shading layer on a monocrystalline silicon wafer and patterning, spin-coating a polysiloxane precursor, curing and stripping to prepare a flexible transparent photoetching template; s2, conformally attaching a template to the cleaned bent metal surface, and performing ultraviolet exposure and development to form a cured photoresist mask; and S3, the metal workpiece with the mask serves as an anode, the metal workpiece with the mask is placed in HF-HCl mixed electrolyte for electrochemical etching, the voltage is controlled to be 2.0-5.0 V, the time is 2-8 min, and the micron-sized surface texture of 0.5-2.5 microns is obtained. And the thickness of the template is 0.3-3.0 mm, so that the template can adapt to metal surfaces with different curvature radiuses. According to the method, the photoetching-electrochemical etching process is successfully extended to the curved metal surface for the first time, the pattern fidelity is high, the texture depth is controllable, and the method can be widely applied to key parts, needing mechanical sealing and lubricating, of a carrier vehicle body.

The invention discloses a copper-diamond composite board with high heat conductivity and low expansion coefficient and a preparation method thereof, and belongs to the technical field of preparation of heat-conducting packaging materials for electronic equipment. The preparation method comprises the following steps: grinding and cleaning a base copper plate, milling a rectangular groove to obtain a pretreated base copper plate, and performing electrochemical etching on the pretreated base copper plate to obtain an etched base copper plate; filling a rectangular groove in the etched base copper plate with the carbon nano tube and modified diamond, and compacting for 1-2 minutes under 20-30 MPa to obtain a mixed base copper plate; and the copper covering plate covers one side of the mixed base copper plate filled with the carbon nano tube modified diamond, and then the mixed base copper plate is placed in a graphite mold to be subjected to direct current hot pressing sintering to obtain the copper-diamond composite plate. The prepared copper-diamond composite board has good heat conduction performance and low thermal expansion performance, the bending strength is high, and the problem that the brittleness of the material is too high is effectively solved.

The present invention relates to the technical field of semiconductor processing, and provides an electrochemical etching method and an electrochemical etching device. The electrochemical etching method comprises: performing metallization treatment on the back surface, on which etching is not needed, of an object to be etched, and forming a metal layer on the back surface of said object; and performing electrochemical etching treatment on the front surface, on which etching is needed, of said object. Before the electrochemical etching treatment, metallization treatment is firstly performed on the back surface of said object, so that the resistance of said object can be greatly reduced, effectively avoiding the edge effect of said object; and the potentials at positions of the surface of said object can be accurately controlled by energizing the metal layer on the back surface of said object, so that the potentials at the positions of said object are kept consistent, and uneven current density distribution in the etching process is avoided, thereby accurately controlling the etching rate of said object, and greatly reducing the difficulty of electrochemical etching of said object having poor conductivity.

The invention relates to a method for producing an electronic component. The method comprises: forming a first semiconductor layer of a first material on a substrate of a second material, wherein the first material differs from the second material; forming a dielectric structure on the first semiconductor layer, wherein the dielectric structure has a plurality of openings, and in the openings the first semiconductor layer is exposed; epitaxially forming a second semiconductor layer on the first semiconductor layer, which in the openings is exposed, and at least in a region above the dielectric structure, wherein the second semiconductor layer comprises or is formed from the first material; and forming a third semiconductor layer on or above the second semiconductor layer in a first region above the openings of the dielectric structure and in a second region above the dielectric structure. The method also comprises: forming a sacrificial structure on the second semiconductor layer; forming the third semiconductor layer on the sacrificial structure; and removing the sacrificial structure such that the third semiconductor layer is separated from the second semiconductor layer.

The invention relates to a preparation method of an epitaxial structure with micron holes and the epitaxial structure, and belongs to the technical field of epitaxial wafer manufacturing. Comprising the following steps: sequentially growing an AlN buffer layer, a Si-doped 3D AlN layer containing a nano-scale air gap, a high-temperature AlN layer, an n-type AlGaN layer, a multi-quantum well active layer, an electron barrier layer, a p-type AlGaN layer and a p-type GaN contact layer on the surface of a substrate; etching a region corresponding to the n electrode in the epitaxial structure until the air gap is exposed; growing a SiO2 protective layer; enlarging a nano-scale air gap to a micron-scale air gap through electrochemical etching; and preparing a p electrode metal layer on the p-type GaN contact layer, and preparing an n electrode metal layer on the micron-level air gap of the Si-doped 3D AlN layer to obtain an epitaxial structure with micron holes. According to the invention, the nanoscale fusiform air gap is expanded to the micron scale by using the dry etching process and the electrochemical etching process, so that the light extraction efficiency is improved.

The invention discloses a chitosan-conductive carbon black laminated electrode as well as a preparation method and application thereof, and belongs to the field of environment-friendly materials. The method comprises the following steps: activating a carbon felt in a sodium nitrate solution through electrochemical etching to prepare a modified carbon felt carrier; coating a carrier with the precursor solution, vacuumizing, and soaking and strengthening by using a sodium hydroxide-nitrilotriacetic acid trisodium salt monohydrate strengthening solution, so that a stable CS active layer is formed on the surface; sP, polyethyleneimine and dilute sulphuric acid are dissolved in water, and an electrophoresis solution is obtained; carrying out electrophoresis on the electrode with the active layer in an electrophoresis solution to form an SP conductive layer on the surface of the electrode; after a plurality of layers are laminated by multiple times of coating reinforcement-electrophoresis attachment cycle operation, the electrode is placed in a freezing reinforcement solution in isopropanol-glycerol to be frozen for secondary reinforcement, and then the electrode is taken out, unfrozen and cleaned to finally prepare the CS-SP laminated electrode. The electrode material provided by the invention has good electro-adsorption removal performance on heavy metal ions in water.

The application provides a preparation method of an aluminum foil current collector, an aluminum foil current collector, a positive pole piece and a lithium ion battery, and relates to the technical field of new materials for energy storage devices. The preparation method of the aluminum foil current collector comprises the following steps: performing pretreatment on the surface of a base material aluminum foil with a purity of 99.7% or above, so that the surface reaches a du Nouy value of 64 dyne / cm or above, to obtain a pretreated base material aluminum foil; performing electrochemical etching treatment on the pretreated base material aluminum foil, to obtain an etched base material aluminum foil; performing cleaning on the etched base material aluminum foil, and then performing post-treatment, so that a phosphating film is formed on the surface, to obtain the aluminum foil current collector. The preparation method of the aluminum foil current collector is an etched aluminum foil current collector for high-safety lithium ion batteries and a preparation method, and can solve the problems that the safety is not good enough when a conventional current collector is used to prepare a lithium ion battery, and the mechanical property of a high-purity aluminum foil is poor after etching.

The invention discloses a vertical cavity surface emitting laser and a preparation method thereof, and the method comprises the steps: sequentially forming a first epitaxial layer, a sacrificial layer, a second epitaxial layer and a first DBR reflection layer on a first substrate, and the second epitaxial layer at least comprises an active layer; performing graphical processing on the first DBR reflecting layer, the second epitaxial layer and the sacrificial layer; etching the graphical sacrificial layer by adopting an electrochemical etching method so as to integrally strip the graphical second epitaxial layer and the graphical first DBR reflecting layer from the first epitaxial layer; bonding the stripped patterned first DBR reflecting layer and the stripped patterned second epitaxial layer with a second substrate; and forming a patterned second DBR reflecting layer on one side, far away from the patterned first DBR reflecting layer, of the patterned second epitaxial layer to obtain the VCSEL. By arranging the sacrificial layer to cooperate with electrochemical etching, the smoothness of the surface of the stripped epitaxial layer can be improved, so that the luminous efficiency and stability of the VCSEL are improved.

This invention discloses a peelable nitride structure, its preparation method, and its peeling method. The peelable nitride structure includes a substrate, a buffer layer, a sacrificial layer, an etching layer, and a target nitride structure arranged sequentially. The sacrificial layer has through-cracks. Because a sacrificial layer with through-cracks is introduced into the buffer layer and the target nitride structure, the through-cracks provide flow channels for the solution, allowing for rapid etching of the etching layer via electrochemical etching to achieve peeling of the target nitride structure from the substrate and the buffer layer.

The invention relates to the field of batteries, in particular to a low-internal-resistance vanadium redox flow battery electrode material and a preparation method and application thereof. The preparation method of the low-internal-resistance vanadium redox flow battery electrode material comprises the following steps: carrying out plasma activation treatment on an electrode base material to obtain an activated electrode material; the method comprises the following steps: mixing a bimetallic MAX phase compound with a fluorine-containing salt solution, and carrying out electrochemical etching to obtain an MXene material; the preparation method comprises the following steps: dispersing an MXene material in water, and adding carbon nanotubes and a surfactant to obtain a dispersion liquid; dipping the activated electrode material in the dispersion liquid, and carrying out hydrothermal reaction to obtain an intermediate product; dipping the intermediate product in a dopamine hydrochloride solution containing metal salt, adopting a pulse electrochemical deposition method layer, and then performing carbonization and activation treatment in sequence to obtain the low-internal-resistance vanadium redox flow battery electrode material. The low-internal-resistance vanadium redox flow battery electrode material provided by the invention can effectively reduce electrode polarization, improve the energy utilization rate and prolong the service life.

The invention discloses a preparation method and device of a hair follicle-like composite microstructure. According to the method, by means of the thermal deformation performance of the memory alloy material, the electrode deformation section made of the memory alloy material goes deep into the pit formed in the surface of the cutter through laser machining, the deformation section is heated to be in a circular arc shape, and an electrochemical etching method is adopted; an electrochemical system formed by an electrode, a cutter, a power supply device and electrolyte in the pit is used for enabling the rotating electrode to etch the pit into hair follicle structures, then flocking glue doped with magnetic particles is injected into the hair follicle structures, fiber bundles are implanted into the hair follicle structures, and then the hair follicle structures are formed. And after flocking is completed, the magnetic particles in the hair follicle structures are magnetized, and then the work of preparing the hair follicle-imitating composite microstructure on the surface of the tool is completed. According to the prepared cutter surface hair follicle-imitating composite microstructure, the cutter can achieve the continuous wetting effect in the working process, the good wetting performance is achieved, and then the cutting performance of the cutter is improved.

The invention relates to the technical field of semiconductor materials, in particular to a method for growing a high-quality GaN crystal through a porous GaN micron pyramid structure. The method comprises the following steps: providing a GaN substrate, and arranging a mask with regular periodic patterns on the surface of the GaN substrate to obtain a pattern substrate; wherein the regular periodic pattern is an array formed by a plurality of pores, and the pores can expose the GaN substrate; growing a GaN pyramid in the pores of the pattern substrate so as to construct a micron GaN pyramid array in the pattern area of the pattern substrate; etching a porous structure on the micron GaN pyramid array by using electrochemical etching to obtain a substrate with the porous micron GaN pyramid array; and taking the porous micron GaN pyramid array as a seed crystal, and carrying out epitaxial growth by using an HVPE method to obtain the target GaN crystal. According to the invention, the GaN crystal with large size, low defect density and high crystal quality can be prepared.

The invention relates to a conductive carrier load defect and rare earth co-regulated layered double hydroxide catalyst as well as a preparation method and application thereof, and belongs to the field of preparation of value-added products by oxidation of organic matters. The preparation method comprises the following steps: dissolving a transition metal source, a rare earth salt, an aluminum source, a precipitator and ammonium fluoride in a solvent, carrying out surface controllable growth with a conductive carrier in a hydrothermal kettle through a hydrothermal reaction, and drying to obtain the conductive carrier loaded rare earth regulated layered double metal hydroxide; and carrying out electrochemical etching on the conductive carrier loaded rare earth regulated layered double metal hydroxide in an alkali solution, washing and drying to obtain the conductive carrier loaded defect and rare earth co-regulated layered double metal hydroxide catalyst. According to the invention, defects and rare earth regulation are creatively combined, the method has the green synthesis characteristics of cheap raw materials, low energy consumption, no noble metal addition and the like, and a new normal form is provided for developing a low-cost and high-stability non-noble metal electrocatalyst.

A method forms a part of a power semiconductor device. The method includes homoepitaxially forming two silicon carbide layers on a first side of a silicon carbide substrate and forming a pattern of pits on a second side of the silicon carbide substrate. The two layers include a buffer layer, on the first side of the silicon carbide substrate, and have a same doping type of the silicon carbide substrate and a doping concentration equal to or greater than 1017 cm−3 in order to increase the quality of at least one subsequent SiC layer. The two layers include an etch stopper layer, being deposited on the buffer layer and has a same doping type as the buffer layer but a lower doping concentration in order to block a trenching process. The pattern of pits, obtained by electrochemical etching, extends completely thorough the silicon carbide substrate and the buffer layer.

The invention provides a microporous copper foil preparation method, which comprises: mixing an oxidizing agent, a corrosion inhibitor, a complexing agent, a surfactant and water, and adjusting the pH value to obtain a corrosive liquid; performing electrochemical etching in the corrosive liquid by taking the electrolytic copper foil as an anode and a cathode plate at a specific point location as a cathode to form a copper foil; and cleaning the etched copper foil, and passivating the cleaned copper foil in an anti-oxidation solution to obtain the microporous copper foil. The method provided by the invention comprises the following steps: taking a copper foil as a corrosive anode, forming an electrolytic tank with a cathode plate at a specific point location and a corrosive liquid, carrying out site oxidation on the surface of the copper foil through an oxidant, and carrying out acid corrosion on the site to form a blind hole; in order to ensure that the corrosion degree of the copper foil is consistent, blind holes are formed, a corrosion inhibitor, a surfactant and a complexing agent are combined, and the corrosion rate of the copper foil is reduced; the method can effectively control the formation of copper foil micropores and the size of the pore diameter.

According to the electrochemical etching preparation method of the porous battery aluminum foil, the porosity, uniformity and surface performance of the aluminum foil are remarkably improved through the steps of multi-stage gradient annealing treatment, pulse voltage electrochemical etching, segmented ultrasonic cleaning, surface modification treatment and the like; according to the method, a composite electrolyte system is adopted to collaboratively optimize the etching effect, and accurate regulation and control of the aluminum foil hole structure are achieved by controlling the waveform of pulse voltage, the ratio of forward voltage to reverse voltage and illumination auxiliary conditions; in addition, the cleanliness and the interface bonding force of the aluminum foil are further improved through segmented ultrasonic cleaning and silane coupling agent surface modification, the surface activity is enhanced through low-temperature plasma treatment, and compared with a traditional method, the aluminum foil prepared through the method has higher mechanical strength, more uniform pore distribution and more excellent electrochemical performance; the energy density and the cycle life of the battery can be remarkably improved, and the method is suitable for the fields of high-performance lithium ion batteries and the like.

According to the electrochemical etching method for the anode foil of the high-voltage tantalum capacitor, the tantalum foil is pre-oxidized before etching processing, isotropic etching of the tantalum foil can be achieved by controlling the thickness of an oxidation film on the surface of the tantalum foil, and therefore circular corrosion holes are formed; the corrosion hole with the morphology can eliminate the limitation of adverse crystal face orientation on the depth of the corrosion hole to the greatest extent; then, pulse current is used for hole forming, so that the density of initial corrosion holes can be improved; on the basis, direct current and constant current are used for reaming, so that the diameter and depth of a corrosion hole can be further increased; and finally, enabling the etched tantalum foil to form the high-voltage tantalum capacitor anode foil with high specific volume. The capacitance density of the tantalum anode foil formed by the method can reach 92.6 nF / mm < 2 > under the voltage of 100V, which is about 6 times higher than that before the process is improved. Therefore, the performance of the anode foil of the high-voltage tantalum capacitor is effectively improved.