1995 results about "Ammonium fluoride" patented technology

A method of removing at least a portion of a silicon oxide material is disclosed. The silicon oxide is removed by exposing a semiconductor structure comprising a substrate and the silicon oxide to an ammonium fluoride chemical treatment and a subsequent plasma treatment, both of which may be effected in the same vacuum chamber of a processing apparatus. The ammonium fluoride chemical treatment converts the silicon oxide to a solid reaction product in a self-limiting reaction, the solid reaction product then being volatilized by the plasma treatment. The plasma treatment includes a plasma having an ion bombardment energy of less than or equal to approximately 20 eV. An ammonium fluoride chemical treatment including an alkylated ammonia derivative and hydrogen fluoride is also disclosed.

An etching solution for silicon oxide may be used in a process for enlarging an opening formed through a silicon oxide layer. The etching solution includes about 0.2 to about 5.0 percent by weight of a hydrogen fluoride solution, about 0.05 to about 20.0 percent by weight of an ammonium fluoride solution, about 40.0 to about 70.0 percent by weight of an alkyl hydroxide solution and remaining water. The etching solution may etch the silicon oxide layer without damage to a metal silicide layer exposed by the opening.

The present invention is a method, process and apparatus for selective cleaning, drying, and modifying substrate surfaces and depositing thin films thereon using a dense phase gas solvent and admixtures within a first created supercritical fluid antisolvent. Dense fluids are used in combination with sub-atmospheric, atmospheric and super-atmospheric plasma adjuncts (cold and thermal plasmas) to enhance substrate surface cleaning, modification, precision drying and deposition processes herein. Moreover, conventional wet cleaning agents such as hydrofluoric acid and ammonium fluoride may be used with the present invention to perform substrate pre-treatments prior to precision drying and cleaning treatments described herein. Finally, dense fluid such as solid phase carbon dioxide and argon may be used as a follow-on treatment or in combination with plasmas to further treat a substrate surface.

Methods for processing a substrate are described herein. Methods can include positioning a substrate with an exposed surface comprising a silicon oxide layer in a processing chamber, biasing the substrate, treating the substrate to roughen a portion of the silicon oxide layer, heating the substrate to a first temperature, exposing the exposed surface of the substrate to ammonium fluoride to form one or more volatile products while maintaining the first temperature, and heating the substrate to a second temperature, which is higher than the first temperature, to sublimate the volatile products.

Methods for processing a substrate are described herein. Methods can include positioning a substrate comprising silicon in a processing chamber, delivering a plasma to the surface of the substrate while biasing the substrate, exposing the surface of the substrate to ammonium fluoride (NH₄F), and annealing the substrate to a first temperature to sublimate one or more volatile byproducts.

The invention includes methods in which silicon is removed from titanium-containing container structures with an etching composition having a phosphorus-and-oxygen-containing compound therein. The etching composition can, for example, include one or both of ammonium hydroxide and tetra-methyl ammonium hydroxide. The invention also includes methods in which titanium-containing whiskers are removed from between titanium-containing capacitor electrodes. Such removal can be, for example, accomplished with an etch utilizing one or more of hydrofluoric acid, ammonium fluoride, nitric acid and hydrogen peroxide.

The formulations of the present invention etch doped silicon oxide compounds, such as BPSG and PSG layers, at rates greater than or equal to the etch rate of undoped silicon oxide such as thermal oxide. The formulations have the general composition of a chelating agent, preferably weakly to moderately acidic (0.1-10%; preferably 0.2-2.8%); a fluoride salt, which may be ammonium fluoride or an organic derivative of either ammonium fluoride or a polyammonium fluoride (1.65-7%; preferably 2.25-7%); a glycol solvent (71-98%; preferably 90-98%); and optionally, an amine.

The invention discloses a preparation method of a ferro-nickel bi-metal hydroxide of a sheet structure on foamed nickel through in-situ growth, and belongs to the field of electrochemistry. Nickel nitrate hexahydrate, iron nitrate nonahydrate, urea, ammonium fluoride and foamed nickel are adopted as main raw materials, and an electrocatalyst through water electrolysis oxygen production is successfully prepared. The sheet structure of the catalyst supplies abundant active sites, due to existence of substrate foamed nickel, the electrical conductivity is enhanced, and when the hydroxide is adopted as the electro-catalysis oxygen production catalyst, the excellent catalysis activity is shown. The activity of a traditional non-noble metal material under an oxygen evolution reaction (OER) in analkaline electrolyte is not ideal. Accordingly, the OER catalysis performance of the non-noble metal material under the alkaline condition is improved, and the method is of great significance in solving the fossil fuel energy crisis. Nickel and iron earth reserve volumes are quite abundant, the OER catalytic performance of the ferro-nickel bi-metal hydroxide of the sheet structure under the alkaline condition is excellent, and the hydroxide is a catalytic material with the wide prospect.

The invention relates to a method for preparing fluorescent nano material converted on NaYF4, comprising the steps: yttrium nitrate, ytterbium nitrate and erbium nitrate or yttrium chloride, ytterbium chloride, erbium chloride and thulium chloride are dissolved in de-ionized water according to the mixture radio that the mol ratio of rare earth ions which are yttrium ion, ytterbium ion and erbium ion is equal to (70-95): (1-25): (0.5-10), so that the mixed solution is prepared; water soluble polymer having the ligand radical with the rare earth ions is added into the mixed solution for stirring reaction to form complex compound; the pH value of the mixed solution is adjusted to be 2-6; sodium fluoride, ammonium fluoride or hydrofluoric acid can be added into the mixed solution and stirred until colloid solution that is approximately transparent is obtained; then, the colloid solution is put into a high pressure closed reactor and heated at the temperature of 140-200 DEG C; after that the obtained product is cooled to be the room temperature, centrifugated, separated, washed and dried, finally, the fluorescent nano material converted on NaYF4 is obtained. The method can be used for preparing the converted material at lower temperature, the particle size and the appearance can be controlled, and the water-solubility is good.

The invention provides an electrocatalyst with a cobalt-based multi-stage nano-composite structure for oxygen production by electrolysis of water and a preparation method of the electrocatalyst. The preparation method comprises the following steps: dissolving cobalt nitrate hexahydrate, urea and ammonium fluoride in deionized water to obtain a precursor solution; transferring the precursor solution into a hydrothermal reactor; adding carbon fiber paper; enabling basic cobalt carbonate nanowires to grow on the carbon fiber paper through solvothermal reaction; after finish of reaction, naturally cooling; then taking out a product; washing and drying to obtain a carbon fiver paper loaded basic cobalt carbonate nanowire composite structure; by taking powdered sulfur as the raw material, preparing a carbon fiber paper loaded cobalt sulfide nanowire composite structure through low-temperature sulfuration reaction under the condition of an inert gas; and finally, electroplating the surface of the carbon fiber paper loaded cobalt sulfide nanowire composite structure with a layer of cobalt hydroxide nanosheets by use of the electrochemical deposition method so as to obtain the electrocatalyst with the cobalt-based multi-stage nano-composite structure for oxygen production by electrolysis of water. As the sulfide and the hydroxide of transition metal cobalt are adopted as the catalyst, in comparison with noble metals, the cost of the catalyst is lowered.

The invention discloses a composite visible-light catalyst for TiO2 microsphere and g-C3N4, as well as a preparation method and an application of the catalyst. The preparation method comprises the following steps of: putting a cleaned titanium sheet to a mixed aqueous solution of melamine and ammonium fluoride to carry out a hydrothermal reaction; and collecting precipitate in a reaction solution after the reaction solution is cooled, cleaning the precipitate, drying and burning the cleaned precipitate to acquire the composite visible-light catalyst for TiO2 microsphere and g-C3N4. The composite visible-light catalyst overcomes the defects of low photo-transformation efficiency and low activity of a single material, has the advantages of an extensive photo-response range, high visible light catalytic activity and the like, and can be applied to the environment-friendly field, in particular an occasion that visible light catalyzes and degrades organic pollutants in water and kills pathogenic microorganisms in the water, thus the application prospect is extensive.

The invention discloses a production method of the patterned sapphire substrate for the nitride epitaxial growth, which comprises the following steps: a silica coating is deposited on the sapphire substrate used for the nitride epitaxial growth; a general photetch technology is utilized to prepare a mask of photetch patterns; the photetch patterns are etched on the silica coating by utilizing the doped liquid of hydrofluoric acid, ammonium fluoride and H2O; with the patterned silica coating as a mask, the sapphire substrate are etched by adopting the doped liquid of sulphuric acid and phosphoric acid in a wet manner so that the patterns are etched on the sapphire substrate; a dilute hydrofluoric acid solution is used for wet etching so as to remove the residual silica coating and clean the sapphire substrate, and then the preparation of the patterned sapphire substrate is completed. The production method has the advantages of low cost, preventing the sapphire substrate from being damaged by dry etching, etc. The patterned sapphire substrate can be used for the epitaxial growth of nitrides with low dislocation density and high crystal weight.

The invention relates to potassium feldspar decomposition and comprehensive utilization technology and in particular relates to a process for decomposing potassium feldspar by adopting a low-temperature semidry method for comprehensive utilization. The process comprises the steps of fully mixing potassium feldspar, fluorite and sulfuric acid, then adding the mixture to a converter reactor to react at 180-250 DEG C, separating SiF4 and HF generated through a reaction from a system under the condition of negative pressure, carrying out absorption with ethanol and water solution to prepare white carbon black, recovering fluorine resources in the process from the solution in the forms of ammonium fluoride and other aids by adopting the method of adding ammonia water and applying the recovered fluorine sources to decomposition of potassium feldspar and carrying out a series of processes such as extraction on the solids after a reaction to obtain calcium sulfate whisker, potassium fluosilicate, aluminium hydroxide and ferric sulfate products. Compared with the method for decomposing potassium feldspar by a high temperature method, the process has the advantages that the reaction conditions are mild and the requirements for equipment are lower; the white carbon black is directly prepared through gas hydrolysis, thus avoiding the tedious course from solid phase separation; and the fluorine resources introduced to the decomposition course are recycled by adopting the mode of ammonium fluoride, thus avoiding waste of the fluorine resources.

The present invention relates to nanometer porous WO3 material, and is especially nanometer porous WO3 material formed through molecule self-assembling and with homogeneous structure, pore diameter of 60-150 nm, regular arrangement and (002) face oriented monoclinic system structure. The nanometer porous WO3 material is prepared through a constant current anode oxidation process with metal W substrate and electrolyte solution, which consists of inorganic fluoride sodium fluoride, potassium fluoride or ammonium fluoride and inorganic strong acid hydrofluoric acid, hydrochloric acid or sulfuric acid and has F- ion concentration of 0.05-0.3 mol/L and H+ ion concentration of 0.05-0.5 mol/L. The nanometer porous WO3 material has high photocatalytic capacity and is one kind of high efficiency photocatalyst.

The invention provides a NiFeP bifunctional transition metal phosphide catalyst which has a nanosheet structure, wherein the nanosheet has a length of 2-5 m and a thickness of 100-200 nm; the invention also provides a preparation method and use of the NiFeP bifunctional transition metal phosphide catalyst. The NiFeP bifunctional transition metal phosphide catalyst provided by the invention has a microstructure that the nanosheet having a relatively large specific surface area is used as a water-splitting electro-catalyst, so that the catalyst has higher catalytic performance. The preparation method provided by the invention comprises the following steps: using ferronickel compound, ammonium fluoride and urea as raw materials; growing NiFe-LDH nanosheets on a substrate under heat preservation; and phosphating at a low temperature to obtain NiFeP transition metal phosphide nanosheets. The operation is simple; the production cost is low; and the prepared phosphide catalyst is applied to full hydrolysis in an alkaline environment and has excellent full hydrolysis catalyzing performance.

The invention relates to an etchant composition and an etching method, wherein, the etchant composition comprises any two components of oxidants, acid and salt, and the pH value of the etchant composition is between 1 and 7. The oxidant components are selected from hydrogen peroxide, ammonium persulfate, potassium persulfate and ceric ammonium nitrate; the acid components are selected from chloric acid, perchlorate, acetic acid, nitric acid, hydrofluoric acid, sulfuric acid and oxalic acid, and the salt components are selected from ammonium fluoride, ammonium bifluoride, diammonium phosphate, ammonium phosphate, ammonium chloride and perfluorinated octyl sulfanilic acid (C8F17SO3NH4).

The invention discloses a method for producing high-quality sodium fluoride from fluorine-containing wastewater as a raw material. The method comprises the following steps: directly adding excessive sodium carbonate into the fluorine-containing wastewater to completely crystallize and separate fluorine in the solution in a mode of sodium fluoride, or firstly, adding amino into the fluorine-containing wastewater so as to obtain an ammonium fluoride solution, or firstly, precipitating and enriching the fluorine in the fluorine-containing wastewater, secondly, converting a precipitated and enriched product into an ammonium fluoride solution by using an ammonium salt solution, adding excessive sodium carbonate into the ammonium fluoride solution to completely crystal and separate the fluorine in the mode of sodium fluoride, and filtering so as to obtain sodium fluoride filter cakes and a post fluorine precipitation liquid; and washing the sodium fluoride filter cakes by using the ammonium fluoride solution, drying so as to obtain a high-quality sodium fluoride product of which the purity is up to 99.25% or greater, crystallizing the post fluorine precipitation liquid to recycle sodium carbonate in the post fluorine precipitation liquid, further desalting a sodium carbonate crystallization mother liquid, and recycling reclaimed water. The method has the advantages of being simple and convenient to operate, high in fluorine recycling rate, low in production cost, good in sodium fluoride product quality, free of fluorine-containing waste and the like.

The desulfurization of fossil fuels is effected by the combination of fossil fuels with an aqueous mixture of hydroperoxide and quaternary ammonium fluoride phase transfer catalyst, the mixture then subjected to ultrasound to oxidize sulfur compounds present in the fuels. The polar oxidized species are removed via extraction. Another aspect is a portable, continuous ultrasound assisted desulfurization device having a sonoreactor for subjecting mixtures of fossil fuels to sonication to effect removal of sulfur containing compounds.

The present invention provides cobaltosic oxide hierarchical structure nano array materials and a preparation method thereof, and an application of cobaltosic oxide hierarchical structure nano array materials. In a closed high temperature and high pressure reactor, redistilled water is taken as reaction solvent, cobalt salt, ammonium fluoride and urea are added into the reaction solvent for uniform mixing, and a reaction system is heated to generate a high-pressure environment to prepare cobaltous hydroxide precursor nanowire materials; then redistilled water is taken as reaction solvent, 2-methylimidazole is added into the reaction solvent, the cobaltous hydroxide precursor loaded on carbon cloth is immersed in the solution, the cobaltous hydroxide is taken as a cobalt source, the reaction system is heated and the reaction time is controlled to control a ZIF67 nucleation rate so as to prepare a cobalt-based metal organic framework (ZIF67) array; and finally, calcining decomposition ofthe cobalt-based metal organic framework (ZIF67) array is performed to obtain a cobaltosic oxide hierarchical structure. The product purity is high, the dispersibility is good, the controllability isgood, the production cost is low, the reproducibility is good, the cobaltosic oxide hierarchical structure nano array materials have cycling stability and large active surface area, and have a potential application value at the aspect of supercapacitors.

Methods for processing a substrate are described herein. Methods can include positioning a substrate with an exposed surface comprising a silicon oxide layer in a processing chamber, biasing the substrate, treating the substrate to roughen a portion of the silicon oxide layer, heating the substrate to a first temperature, exposing the exposed surface of the substrate to a plasma comprising ammonium fluoride to form one or more volatile products while maintaining the first temperature, and heating the substrate to a second temperature, which is higher than the first temperature, to sublimate the volatile products.

The invention discloses a new preparing method of manganese sulfate through manganese oxide in the manganese ore in the leaching manganese ore extracting and manufacturing technological domain, which comprises the following steps: grinding manganese ore; moulding ore paste through water; adding sulfuric acid and waste molasses in the ore paste; stirring at 40-100 deg.c to obtain leaching liquid; neutralizing the leaching liquid through limestone; adding ammonia sulfate to remove heavy metal ion; adding ammonium fluoride solution to remove Ca2+, Mg2+; evaporating; condensing; crystallizing; drying to produce manganese sulfate with over 98 percent purity and 93 percent manganese collecting rate.

The invention relates to an in-situ grown three-dimensional multi-structural cobaltosic oxide/carbon composite micro-nanomaterial and its controllable preparation method. A cobalt material, ammonium fluoride and urea are used as raw materials to prepare a cobaltosic oxide micro-nanomaterial with multiple specific-morphologies three-dimensional multi-structures in situ; and the cobaltosic oxide micro-nanomaterial is processed with a carbon-rich solution to obtain a corresponding three-dimensional multi-structural carbon-coated cobaltosic oxide composite structure. The preparation method provided by the invention is simple, has strong operationality, is low-cost and is green and environmentally friendly. Problems of tedious steps, poor combinability between a nano-powder and a substrate, poor repeatability, poor electron-transporting property and the like when the traditional nano-powder is used in a device are solved. The three-dimensional multi-structures and specific morphology of cobaltosic oxide can be effectively maintained. The obtained product has diversified morphologies, is uniform in size, is not easy to agglomerate and has high purity. The three-dimensional pores and multi-structures of the product are beneficial to electron-transport. The product will be hopefully and widely applied in fields of supercapacitor, lithium ion battery, catalysis, magnetic material, sensor, photoelectricity and the like.