Abstract: In the formation of a magnetic recording head or other electronic device on a substrate, at least one thin nickel iron-film is deposited on the substrate and an element is formed by etching the film. The film is first activated by disposing the film in a hydrochloric acid activating solution containing a ferrous salt. After activation, the film is removed from the activating solution and the hydrochloric acid rinsed away from the substrate. Then, the film is etched by disposing it in a sulfuric acid bath containing a ferric salt. After etching, the film is rinsed with sulfuric acid. The process substantially avoids residual corrosion of the resulting head that otherwise would be caused by chloride lingering in the etched portions of the head.

Abstract: An identification label for permanently marking a metal or other etchable surface such as an automobile part with an identifying indicia is disclosed. The label has a protective cover sheet, a pressure sensitive adhesive irremovably affixed to the cover sheet, and a liner with a release coating removably affixed to the adhesive. An identifying indicia comprising an etchant in a visible vehicle such as a printing ink is printed on the adhesive at the interface of the removable liner and the adhesive so that when the liner is removed, the remaining portions of the label may be adhesively attached to the metal surface with the etchant of the identifying indicia in etching contact therewith. The identifying indicia will thus be etched into the surface of the part for a permanent marking of the part.

Abstract: A wet chemical process is provided for treating an emitter formed on a substrate of a field emission display, the process comprises applying a solution including hydrogen to the emitter. In one embodiment of the invention, the steps of applying a solution comprises applying a solution of hydrofluoric acid to the emitter.

Abstract: A process and composition for treating a metal surface to increase its surface roughness for subsequent adhesion to a polymer layer. The composition comprises hydrogen peroxide, inorganic acid, an amine free of a surfactant group and optionally, a corrosion inhibitor. The composition is characterized by elimination of a surfactant from solution.

Abstract: The gate oxide film is prevented from being thinned partially. The semiconductor substrate (wafer) can be etched (processed) under excellent conditions. The impurities on the wafer surface can be analyzed and further reduced. In the first aspect, the substrate is irradiated with ultraviolet rays in contact with an F-containing aqueous solution, so that the oxide film and the substrate can be etched at roughly the same etching speed under excellent controllability without deteriorating the planarization of the substrate. In the second aspect, the substrate is etched by irradiating ultraviolet rays during exposure to an acid aqueous solution, so that surface metallic contamination and particles can be removed without deteriorating the wafer surface roughness. Further, the impurity elements in the outermost surface layer of the wafer can be analyzed at high precision by analyzing elements contained in the acid aqueous solution used for the etching.

Abstract: A process and etchant solution for chemical wet etching of thin film metals in the presence of a protected metal. The etching solution has a pH range of about 2.7 to 4.0. The etching solution may include hydrogen peroxide, potassium sulfate, and potassium EDTA, and it reduces or eliminates the incidence of etch-resistant metal without damaging the protected metal.

Abstract: A glass fiber capable of withstanding temperatures in excess of 1900.degree. F. is produced by treating a glass, preferably E-glass, fiber. The glass fiber is first leached with selected acids, and then the leached fiber is treated with organo-metallic materials of low viscosity, such as a dispersion of low molecular weight water-in-oil emulsion of dimethyl polysiloxane. The fiber is used in such applications as embedding it in a fire-resistant active coating material or embedding it into one surface of a polyolefin or composite plastic, such as a polypropylene sheet. The treated fiberglass can be used as a sole component or in concert with a fire-resistant or fire retardant material to further enhance its fire-resistant properties.

Abstract: The present invention provides a novel method of etching nickle/iron alloy which employs a novel etchant. The novel etchant, which etches nickle/iron alloy but not copper, comprises an aqueous solution of ferric ammonium sulfate, and an acid selected from the group consisting of: sulfuric acid; phosphoric acid; and mixtures thereof.

Abstract: Method for etching metal oxide films, especially tin oxide on a substrate in which a metal (Zn) is deposited on said film and etching is performed by a mixture of an acid, such as hydrochloric acid (HCl) and a metal dissolution agent, such as ferric chloride. The hydrochloric acid reacts with the zinc to produce active hydrogen which reduces the tin oxide to tin, which in turn is etched with the hydrochloric acid.

Abstract: The invention relates to a method of pickling or surface treating a metal in an aqueous solution containing nitric acid wherein hydrogen peroxide is supplied to decrease the formation of nitrous fumes. At least a portion of the hydrogen peroxide is supplied by spraying or flushing an aqueous solution thereof directly on the metal through one or several separate nozzles (18a, 18b, 19a, 19b).

Abstract: A method for removing a portion of an upper layer of one material from an underlying layer of another material to form a uniformly planar surface on a semiconductor wafer. In accordance with one embodiment of the invention, an upper section of the upper layer is etched to an intermediate point in the upper layer. The etching step removes the upper section of the upper layer and leaves only a lower section of the upper layer on the wafer. The lower section of the upper layer is then planarized to a final endpoint. The etching step preferably moves the majority of the upper layer from the wafer so that the remaining portion of the upper layer is thick enough to allow the planarization step to produce a uniformly planar finished surface on the wafer.

Abstract: A surface of a diamond, particularly a diamond window, is treated by depositing a layer of a carbide-forming metal such as titanium, on the surface and thereafter removing the layer. The treatment has the effect of passivating stress surface defects in the diamond such as grain boundaries, twin defects and polishing damage.

Abstract: Packed bed carburization of a tantalum or tantalum alloy object. A method for producing corrosion-resistant tantalum or tantalum alloy objects is described. The method includes the steps of placing the object in contact with a carburizing pack, heating the packed object in vacuum furnace to a temperature whereby carbon from the pack diffuses into the object forming grains with tantalum carbide along the grain boundaries, and etching the surface of the carburized object. This latter step removes tantalum carbides from the surface of the carburized tantalum object while leaving the tantalum carbide along the grain boundaries.

Abstract: Apparatus for assembling microstructures onto a substrate through fluid transport. The apparatus includes a vessel that contains the substrate, a fluid, and microstructures. The substrate has at least one recessed region thereon. The microstructures being shaped blocks self-align into the recessed regions located on the substrate such that the microstructure becomes integral with the substrate. The apparatus also includes a pump that circulates the microstructures within the vessel at a rate where at least one of the microstructures is disposed into the recessed region.

Abstract: Methods of wet etching through a silicon substrate using composite etch-stop layers are disclosed. In one embodiment, the composite etch stop comprises a layer of silicon dioxide and a layer of polyimide.

Abstract: A wet chemical process is provided for treating an emitter formed on a substrate of a field emission display, the process comprises applying a solution including hydrogen to the emitter. In one embodiment of the invention, the steps of applying a solution comprises applying a solution of hydrofluoric acid to the emitter.

Abstract: In a method of finishing a surface of a floating type magnetic head in which a sliding contact surface opposing a magnetic recording medium is made of a polycrystal material comprising at least two kinds of phases of different compositions mixed together, the sliding contact surface is roughened by treatment with an etching solution in accordance with a chemical etching process. The sliding contact surface of the floating type magnetic head can be mirror-finished with an appropriate surface roughness, so that satisfactory CSS performance and good electromagnetic performance can be obtained. The sliding contact surface is preferably made of a polycrystal ceramic material selected from the CaTiO.sub.3 ceramic system, the AlTiC ceramic system and the MnO-NiO ceramic system. The etching solution contains aqueous hydrogen peroxide as an oxidizing agent and is preferably an aqueous hydrogen peroxide and ammonia solution.

Abstract: The present invention relates to a chemical etchant for etching metals in the presence of one or more metals not to be etched, the etchant comprising 10-25 gms EDTA, 15-35 gms K.sub.2 HPO.sub.4 and 25-45 gms oxalic acid in a liter of 30% H.sub.2 O.sub.2. More particularly, in the fabrication of interconnections for microchip structures, the present invention addresses the removal of intermediate adherent layers, e.g., Ti--W, without damaging other microchip structures made of other metals, such as Al or Al--Cu test pads; Cu and phased Cr--Cu layers; and Sn--Pb solder bumps. The use of potassium phosphate in the hydrogen peroxide+EDTA bath has been found to significantly reduce the attack on the metal not to be etched. Furthermore, the use of oxalic acid in the bath prevented the deposition of tin oxide on the substrate adherent layer metal, thus facilitating its complete removal.

Abstract: A metal, such as Platinum, is stripped from a wafer during processing of an integrated circuit. The wafer, typically within a cassette of wafers, is submerged in de-ionized water. The de-ionized water is, for example, held within a container made of quartz. Optimally, the de-ionized water is heated, for example, to a temperature of 80 degrees Centigrade. Chlorine gas and hydrochloric acid gas are bubbled into the de-ionized water to oxidize the metal.

Abstract: Disclosed is a method for the removal of a layer of photoresist material from a surface of a film located on an in-process integrated circuit wafer subsequent to etching the film through the photoresist material layer. The method disclosed herein comprises first, applying a layer of the photoresist material layer over the film, then patterning the photoresist material, etching the film, and finally, removing the photoresist material. The etch is preferably a wet etch conducted in a closed reaction chamber. The photoresist material removal can be conducted within the same closed reaction chamber as that in which the etch was conducted. Photoresist material removal is achieved by exposing the photoresist material to heated solvent vapors. One particularly advantageous vapor solvent comprises isopropyl alcohol. Subsequent to the photoresist material removal, the film is preferably subjected to cleaning, rinsing, and drying methods, all of which can be conducted within the same closed reaction chamber.

Abstract: The use of lactic acid or its derivative in compositions to etch or polish materials containing indium phosphide results in treated surfaces that have reduced surface roughness compared to the surfaces treated with compositions devoid of lactic acid or its derivative. Indium phosphide surfaces treated with compositions containing lactic acid can have treated surfaces that are smooth or mirror-like, meaning that surface irregularities thereon are less than about 50 .ANG..

Abstract: An improved method for stripping or removing tin or tin/lead plating materials from copper-based alloys is provided. This method is essentially a two-stage process whereby the bulk of the plating layer is removed in the first stage and the remaining intermetallic layer (i.e., the interface between the copper-based substrate and the plating materials) is removed in the second stage. The first stage uses an aqueous etchant solution containing either sulfuric acid and nitric or an alkane sulfonic acid and nitric acid. An aqueous immersion solution containing either sulfuric acid and copper (II) ions or an alkane sulfonic acid and copper (II) ions (which can form complexes with the alkane sulfonic acid such as copper mesylate) is used in the second stage to remove the remaining intermetallic layer. The copper-based substrate, after rinsing with water and is drying (if appropriate), can then be treated using conventional metal-recycling procedures.

Abstract: An etching composition and method for its use in etching a semiconductor structure, the semiconductor structure comprising a substrate and one or more epitaxial layers. The etching composition comprises a solvent, an etchant, and first and second complexing agents, the etchant and complexing agents being soluble in the solvent. The etchant preferentially etches the substrate with respect to at least one epitaxial layer. The first complexing agent is reactive with the substrate so as to accelerate the rate at which the etchant etches the substrate. The second completing agent is reactive with a component of the at least one epitaxial layer so as to form a resulting compound with the component. This reaction establishes an equilibrium between the resulting compound, the second complexing agent and the component, the equilibrium precluding significant etching of the at least one epitaxial layer.

Abstract: A composition that includes an aqueous solution of nitric acid and an additive having the formula ##STR1## or a salt thereof, in an amount sufficient to improve the oxidative stability of the aqueous nitric acid solution relative to the oxidative stability of that aqueous solution in the absence of the additive.

Abstract: A method of improving the breakdown strength of polymer multi-layer (PML) capacitors is provided. The method comprises removing metal, specifically, aluminum, from the cut edge. This is done by either etching back the metal electrode layers in either basic or acidic solution or by anodizing the metal to cover that portion of the metal at the edge with an oxide. Removing the metal from the cut edge increases the breakdown strength of the PML capacitors by a factor of two or more.

Abstract: A process for roughening a metal surface is provided comprising applying a coating to the metal surface wherein the coating is a temporary barrier to an etchant attacking the metal surface and the coating is susceptible to the etchant gradually removing the coating, and then etching the coated metal surface with an aqueous bath containing the etchant effective to produce a roughened metal surface.

Abstract: Slurries and methods for the chemical mechanical polishing of thin films used in integrated circuit manufacturing are described. A first slurry comprises an oxidant, such as water, a halogen, such as fluorine, an abrasive, such as silica, and a chelating agent, such as citric acid, and has a pH between four and nine. The first slurry is ideal for the chemical mechanical polish of an aluminum film. Another slurry comprises an abrasive, such as silica, and an acid, such as citric acid, and has a pH of approximately three. The second slurry is ideal for the chemical mechanical polish of titanium aluminide and is compatible with the first slurry.

Abstract: The present invention is directed to a novel etching process for a semiconductor material which inhibits corrosion of metal comprised of pretreating the material, preferably with a surfactant, and then exposing the material to a mixture comprising salt, a buffered oxide etch, and optionally a surfactant.

Abstract: A method of fabricating an anode plate 80 for use in a field emission device comprising the steps of providing a substantially transparent substrate 70, depositing a layer of a transparent, electrically conductive material 90 on a surface of the substrate, and then removing portions of said layer of conductive material to leave stripes of said conductive material 90.sub.R, 90.sub.G, 90.sub.B. The stripes of conductive material have a first and second corner 84, 88 distal from the substrate 70. The first and second corners 84, 88 of the stripes of conductive material are rounded and luminescent material 74 is applied on the conductive stripes 90. The first and second corners 84, 88 are rounded by applying voltage to the stripes 90 and then etching the stripes to form the rounded corners 84, 88.

Abstract: In accordance with the invention a metal film structure having tapered sidewalls is made by the steps of applying a first layer of metal on a substrate, applying a second layer of a different material over the first layer, forming a pattern of resist on the second layer and etching the first and second layers in an etchant. The material of the second layer is chosen to interact with the metal of the first layer to increase the lateral etch rate of the second layer, thereby producing a metal film structure having tapered sidewalls. In preferred embodiments, the first layer is Cr, the material of the second layer is Mo, and the etchant is ceric ammonium nitrate. The preferred application of the method is to make conductive thin film lines for thin film transistor arrays used in active matrix liquid crystal displays.

Abstract: A method for removing deposited material from vacuum deposition equipment is disclosed. The method utilizes a low temperature bath, between 40-50 degrees F., to strip sputter depositions, followed by an acid etch step using a low concentration of hydrofluoride acid to remove trace contamination from the surface. Following removal of deposited material, surface texturing of the components is provided.

Abstract: Reduced undercutting of a titanium-tungsten layer in a ball limiting metallurgy (BLM) is achieved in the preparation of solder ball interconnect structures by removing metal oxide film which forms on the titanium-tungsten layer and etching the titanium-tungsten layer in different steps. Removing the metal oxide with an acid solution prior to etching the titanium-tungsten layer provides for a more uniform etch of the titanium-tungsten layer.

Abstract: A disordered multicomponent MgNi based electrochemical hydrogen storage material having a microstructure including a substantial volume fraction characterized by intermediate range order and exhibiting extraordinarily high storage capacity and methods of fabricating same.

Abstract: A method is provided for producing superconducting Josephson devices using a chemical etching solution which comprises forming a mask on a predetermined portion of a MgO substrate, and immersing the MgO substrate having the mask in an aqueous acid solution in which the volume ratio of phosphoric acid to sulfuric acid is approximately 10:1 or more, so as to form a step at the boundary between the masked region and the unmasked region.

Abstract: A process is provided for removing slag from an aperture in a substrate, comprising the steps of: providing a protective coating on the substrate; drilling a hole through the substrate; and chemically removing slag from the aperture by complete or partial immersion of the substrate into a chemical bath. Additional process steps can include cleaning the stripped substrate and baking the substrate at a high temperature. A base coating can be provided on the substrate to promote adhesion of a chemically resistant coating to the substrate. Additionally, a protective coating can be applied to the chemically resistant coating to protect it during drilling. The chemically resistant layer can be a material, such as gold, that does not oxidize or dissolve when it is exposed to a chemical, such as phosphoric acid. Phosphoric acid can be heated to accelerate slag removal.

Abstract: Optical quality molds and mold inserts include an optically flat substrate, a layer of material applied to the substrate and one or more depressions in a predetermined pattern formed in the layer of material applied to the substrate. The depth of the depressions are precisely determined by the thickness of the layer applied to the substrate. By contacting the mold with resin in a fluid state, a component is fabricated having microfeatures formed monolithically thereon.

Abstract: A light emitting device (10) incorporates a layer (12) of porous silicon of low dimensionality surmounted by a discontinuous layer of silver in the form of discrete islands (20). A digitated electrode (13) is connected to the islands (20). The islands (20) have diameters in the range 5 nm to 20 nm and spacings in the range 10 nm to 50 nm, and they form a Schottky diode structure on the silicon (12). Under electrical bias, the diode structure conducts and light is generated. The device (10) is produced by vacuum deposition of silver onto a silicon wafer at a temperature which provides for the silver to separate into individual balls (20). The wafer is then anodized to produce a porous layer incorporating columns of silicon and silicon dioxide surmounted by respective silver islands (20). Each silver island (20) protects the underlying silicon (21) from the anodizing medium, and subsequently provides an electrical contact to the silicon.

Abstract: The present invention provides a novel method of etching nickle/iron alloy which employs a novel etchant. The novel etchant, which etches nickle/iron alloy but not copper, comprises an aqueous solution of ferric ammonium sulfate, and an acid selected from the group consisting of: sulfuric acid; phosphoric acid; and mixtures thereof.

Abstract: Methods for producing an adherent diamond film on a cemented metal carbide substrate are disclosed. Particularly, the present invention discloses methods of preparing the surface of a cemented metal carbide surface such that an adherent polycrystalline diamond coating may be deposited thereon using CVD techniques. Cutting tool inserts produced from such adherent diamond film coated cemented metal carbide articles are also disclosed.

Abstract: Stabilizing composition for inorganic peroxides and hydrogen peroxide intended for baths for the surface treatment of metal components comprising at least one activating agent selected from derivatives of benzotriazoles of imidazole and of carboxyimidazoles. Process for the treatment of metal surfaces using the composition at acid pH in the presence of inorganic peroxide. Use of the composition for producing a bath for pickling, polishing or burnishing metals.

Abstract: Novel slurries for the chemical mechanical polishing of thin films used in integrated circuit manufacturing. A tungsten slurry of the present invention comprises an oxidizing agent, such as potassium ferricyanide, an abrasive such as silica, and has a pH between two and four. The tungsten slurry of the present invention can be used in a chemical mechanical planarization process to polish back a blanket deposited tungsten film to form plugs or vias. The tungsten slurry can also be used to polish copper, tungsten silicide, and titanium nitride. A second slurry, which is a 9:1 dilution of the tungsten slurry is ideal for chemical mechanical polishing of titanium nitride films. A third slurry of the present invention comprises a fluoride salt, an abrasive such as silica and has a pH.ltoreq.8. The third slurry can be used to polish titanium films.

Abstract: This invention relates to the removal of lead from spent ferric nitrate based solder strippers, the regeneration of the spent ferric nitrate based solder strippers, and the reuse of these solutions at least one time. It comprises a method and process for precipitating lead salts from used acidic solder strippers which are employed to strip solder coatings, including the underlying tin-copper alloy, from the copper substrate of a printed circuit board. The method includes the use of sulfate ions which are directly added to an aqueous solution of spent solder stripper, without neutralization of the spent solder stripper, optionally in combination with nitric or methylsulfonic acid addition. After precipitation and removal of the lead salts, additional components of the solder stripper composition may be added to substantially restore the initial functioning of the solder stripper.

Abstract: The object of the present invention is to provide a wiring board fabrication process which is, not only so smooth on the surface that a fine wiring pattern can be formed thereon, but also suitable for mounting electronic parts having fine pitch terminals.The present invention is a fabrication process of a wiring board which comprises a wiring conductive line embedded in the surface of an insulating substrate so that the upper face of the conductive line and the surface of the substrate are flat, and a through-hole land which is a conductive portion projected from the surface of the substrate in a through-hole portion, which is characterized in removing the conductive portion projected from the surface of the substrate in the through-hole portion so as to have a flat surface on the surface of the substrate.

Abstract: A method for removing Ball Limiting Metallurgy (BLM) layers from the surface of a wafer in the presence of Pb/Sn solder bumps. In one embodiment, the BLM comprises two layers: titanium and copper. After Pb/Sn solder bumps have been formed over the electrical contact pads of the wafer, the BLM copper layer is etched with a H.sub.2 SO.sub.4 +H.sub.2 O.sub.2 +H.sub.2 O solution. While removing the copper layer, the H.sub.2 SO.sub.4 +H.sub.2 O.sub.2 +H.sub.2 O etchant also reacts with the Pb/Sn solder bumps to form a thin PbO protective layer over the surface of the bumps. When the copper layer has been etched away, the titanium layer is etched with a CH.sub.3 COOH+NH.sub.4 F+H.sub.2 O solution. The PbO layer formed over the surface of the Pb/Sn solder bumps remain insoluble when exposed to the CH.sub.3 COOH+NH.sub.4 F+H.sub.2 O etchant, thereby preventing the solder bumps from being etched in the presence of the CH.sub.3 COOH+NH.sub.4 F+H.sub.2 O etchant.

Abstract: An etching solution for etching away a metal layer from a substrate includes a hydrogen-containing compound that dissolves the metal layer while developing hydrogen; and a nitrosubstituted organic compound having a nitro group which is easily hydratable and which has at least a 1/3 nitro group equivalent per mole of the hydrogen developed by reaction between the hydrogen-containing compound and the metal layer until the metal layer is dissolved completely. A method for etching employs the etching solution into which the substrate is immersed. The process of preventing the release of hydrogen gas during the etching away of a metal layer from a substrate is taught and includes employing an etching solution containing one of an acid or a highly basic metal hydroxide; and adding to the etching solution an organic nitro compound which is soluble in water and which is easily hydratable.

Abstract: An aqueous mixture etchant containing hydroiodic acid and ferric chloride is suitable for etching ITO to form a minute electrode pattern as used in a liquid crystal display device. When the etchant has caused a decrease in etching performance due to a compositional change, it can be effectively regenerated by replenishing appropriate amounts of hydrochloric acid and pure water, or an appropriate amount of a dilute hydrochloric acid at a constant concentration, while minimizing the use of hydroiodic acid and ferric chloride which are rather expensive compared with hydrochloric acid and pure water.