Abstract: A thin discontinuous layer of metal such as Au, Pt, or Au/Pd is deposited on a Group III-V material surface. The surface is then etched in a solution including HF and an oxidant for a preferably brief period, as little as a couple seconds to one hour. A preferred oxidant is H2O2. Morphology and light emitting properties of porous Group III-V material can be selectively controlled as a function of the type of metal deposited, doping type, doping level, metal thickness, whether emission is collected on or off the metal coated areas and/or etch time. Electrical assistance is unnecessary during the chemical etching of the invention, which may be conducted in the presence or absence of illumination.

Abstract: A perforated electrode has strategically distributed flushing holes through which a flushing medium is discharged. The electrode can be used for either electrochemical machining (ECM) or electrodischarge machining (EDM). The flushing medium is either electrolyte in ECM or a dielectric fluid in EDM. It is discharged from the tool electrode directly against the workpiece surface or surfaces which are undergoing material removal. This removes heat and sludge or debris.

Abstract: A method of forming a curved cooling channel into a gas turbine component such as a turbine blade uses an electrode in the form of a helix. The electrode is driven to rotate around the central rotational axis of the helix and axially along the central rotational axis. A turbine blade for a gas turbine component is provided with at least one helical cooling channel.

Abstract: A board 20 is provided with a Cu film 30 as a conformal mask, in which are formed a register mark 30b and an opening 3a through which a via hole is formed. A camera senses this register mark 30b so that the position of the board 30 is determined. A laser beam is directed to the approximate position of the opening 30a, so that the opening 26a through which the via hole is drilled is formed. The accuracy of the position of the opening of the via hole depends on the accuracy of the position of the opening 30a in the Cu film 30 as the conformal mask. Therefore, the via hole can be formed at an adequate position despite the low accuracy of the position for laser irradiation.

Abstract: A substrate made from silicon has a first region and a second region. Through pores are formed in the first region. Pores that do not traverse the substrate are provided in the second region. The production of the work piece is performed with the aid of electrochemical etching of the pores. The entire surface of the substrate is covered with a mask layer that is structured photolithographically on the rear of the substrate. The bottoms of the pores in the second region are etched clear, preferably using KOH.

Abstract: A manufacturing method of a composite type thin-film magnetic head with a reading head element and an inductive writing head element, includes a step of forming the reading head element and its lead conductor layers on a first insulation layer, a step of forming a second insulation layer to cover the reading head element and the lead conductor layers, a step of forming a second shield layer on the second insulation layer, a step of forming a third insulation layer, and a step of forming via holes and a back gap hole. The via holes and back gap hole forming step is executed by reactive ion etching (RIE) for simultaneously removing the second insulation layer and the third insulation layer located at the via holes and the third insulation layer located at the back gap hole.

Abstract: A system and process for cleaning a hollow interior or a passageway of a metal member including an external container having counter electrode material with a higher potential than the metal member with the counter electrode material being dc coupled to the metal member, and electrolyte passing through the container to contact the counter electrode material and fluidicly coupled into the hollow interior or the passageway of the metal member to clean same.

Abstract: Disclosed is an ink jet print head and a method of producing the same, the ink jet print head including a plurality of ink ejecting orifices which are formed with a desired shape and a uniform size by only once using metal plating technique, having an excellent productivity and a low manufacturing cost. According to a first embodiment of the present invention, in the steps for forming an improved metal barrier layer, which is comprised of the conventional barrier layer and the conventional nozzle plate combined together, the metal barrier layer can be formed on a wetting layer by using electrolytic plating or electroless plating of Ni. As a result, an upper surface of a first photoresist mold is completely covered with the overflowing Ni. Further, an upper portion of a second photoresist mold is partially covered with the overplating Ni and is partially opened at a proper size and a desired shape. Thereby, an ink ejecting orifice is created at the upper portion of the second photoresist mold.

Abstract: A novel method to fabricate nanoscale pits on Au(111) surfaces in contact with aqueous solution is claimed. The method uses in situ electrochemical scanning tunnelling microscopy with independent electrochemical substrate and tip potential control and very small bias voltages. This is significantly different from other documented methods, which mostly apply high and short voltage pulses. The most important advantages of the present method are that the dimensions and positions of the pits can be controlled with high precision in aqueous environment so that nanopatterns of the pits can be designed, and that the operations are simple and require no instrumental accessories. Parameters, which control the pit formation and size, have been systematically characterized and show that the primary controlling parameter is the bias voltage. A mechanism based on local surface reconstruction induced by electronic contact between tip and substrate is in keeping with the overall patterns for pit formation.

Abstract: A machining process for forming a raised area in a wall of a predrilled hole includes distributing electrolyte via a workpiece internal cavity to a number of predrilled holes. Next, position a template including at least one electrode coated with an insulating material in a pattern defining the raised area to be formed in the wall of the predrilled hole below the workpiece such that the electrode is positioned within a predrilled hole and machining by passing electric current between the electrode and the workpiece wall and circulating electrolyte through the hole.

Abstract: An improved method of machining slots and material feed holes in a molding die such as an extrusion die designed to form a honeycomb structure of ceramics employed as a catalyst carrier of a catalytic converter for automotive vehicles. In one of the preferred embodiments, shallow holes are drilled in a die material and subjected to electrochemical machining to remove material from the bottoms of the shallow holes so that they communicate with the material feed holes without any burrs. In the other embodiment, the slots are cut using a rotary cutter in a given order which will balance reaction forces exerted on the cutter from both side walls of each slot to minimize deformation of the cutter during cutting of the slots, thereby preventing the slots from being curved undesirably.

Abstract: An improved method of machining slots and material feed holes in a molding die such as an extrusion die designed to form a honeycomb structure of ceramics employed as a catalyst carrier of a catalytic converter for automotive vehicles. In one of the preferred embodiments, shallow holes are drilled in a die material and subjected to electrochemical machining to remove material from the bottoms of the shallow holes so that they communicate with the material feed holes without any burrs. In the other embodiment, the slots are cut using a rotary cutter in a given order which will balance reaction forces exerted on the cutter from both side walls of each slot to minimize deformation of the cutter during cutting of the slots, thereby preventing the slots from being curved undesirably.

Abstract: An electrochemical machine is disclosed for use in an electrochemical machining process to simultaneously generate different levels of metal removal. The electrochemical machine comprises at least two electrodes, each including an electrically conductive cylinder having an external surface partially coated with an insulated coating. The insulating coating is in a pattern defining raised areas to be formed on an internal surface of a predrilled hole in a workpiece wherein at least one of the electrodes has a varied pattern of insulating coating.

Abstract: An electrode for use in an electrochemical machining process comprising an outer metal skin of corrosion resistant material, an inner core of conductive material, and an insulating coating disposed on an external surface of the outer metal skin. The external surface is partially coated with the insulating coating so as to define a pattern of raised areas to be formed on an internal surface of a predrilled hole in a workpiece.

Abstract: It is an object of the present invention to provide an anodizing apparatus capable of efficiently performing anodizing. In order to achieve this object, an anodizing apparatus for anodizing a substrate to be processed in an electrolytic solution includes a process tank for storing the electrolytic solution, the process tank having an opening in a wall, a negative electrode arranged in the process tank to oppose the opening, and a positive electrode contacting a surface of the substrate to be processed which is arranged to close the opening from an inside of the process tank, the surface being open outside the process tank through the opening.

Abstract: An electrochemical machining process is disclosed for forming multiple raised areas having multiple heights in a wall of predrilled holes within a workpiece. Positioned within each hole is an electrode coated with an insulating material in a pattern defining the raised areas to be formed in the wall of each respective hole. An electric current is applied from a power supply to each of the electrodes. A resistor is positioned between the power supply and at least one of the electrodes to vary the voltage passing through the electrode to vary the amount of material removed within that respective hole.

Abstract: A method of removing a metal skin from a through-hole surface of a copper-Invar-copper (CIC) laminate without causing differential etchback of the laminate. The metal skin includes debris deposited on the through-hole surface as the through hole is being formed by laser or mechanical drilling of a substrate that includes the laminate as an inner plane. Removing the metal skin combines electrochemical polishing (ECP) with ultrasonics. ECP dissolves the metal skin in an acid solution, while ultrasonics agitates and circulates the acid solution to sweep the metal skin out of the through hole. ECP is activated when a pulse power supply is turned on and generates a periodic voltage pulse from a pulse power supply whose positive terminal is coupled to the laminate and whose negative terminal is coupled to a conductive cathode. After the metal skin is removed, the laminate is differentially etched such that the copper is etched at a faster rate than the Invar.

Abstract: A method for making a probe device makes use of the main shaft of an electrodischarge machining machine to mount thereon a probe for effecting the drilling operation of a PCB board. Upon completion of the drilling operation, the probe is severed and then fastened with the PCB board.

Abstract: A wet chemical process for etching submicron patterned holes in thin metal layers using electrochemical etching with the aid of a wetting agent. In this process, the processed wafer to be etched is immersed in a wetting agent, such as methanol, for a few seconds prior to inserting the processed wafer into an electrochemical etching setup, with the wafer maintained horizontal during transfer to maintain a film of methanol covering the patterned areas. The electrochemical etching setup includes a tube which seals the edges of the wafer preventing loss of the methanol. An electrolyte composed of 4:1 water: sulfuric is poured into the tube and the electrolyte replaces the wetting agent in the patterned holes. A working electrode is attached to a metal layer of the wafer, with reference and counter electrodes inserted in the electrolyte with all electrodes connected to a potentiostat. A single pulse on the counter electrode, such as a 100 ms pulse at +10.

Abstract: A three-dimensional (3-D) T-load for planar microchannel arrays for electrophoresis, for example, which enables sample injection directly onto a plane perpendicular to the microchannels' axis, at their ends. This is accomplished by forming input wells that extend beyond the ends of the microchannel thereby eliminating the right angle connection from the input well into the end of the microchannel. In addition, the T-load input well eases the placement of electrode in or adjacent the well and thus enables very efficient reproducible electrokinetic (ek) injection. The T-load input well eliminates the prior input well/microchannel alignment concerns, since the input well can be drilled after the top and bottom microchannel plates are bonded together. The T-load input well may extend partially or entirely through the bottom microchannel plate which enables more efficient gel and solution flushing, and also enables placement of multiple electrodes to assist in the ek sample injection.

Abstract: Method and apparatus for electrochemically deburring a diesel injector nozzle workpiece having a gallery cavity and having a first fuel hole and an air hole intersecting the gallery cavity at a first location. A first electrode is inserted into the first fuel hole such that the electrode tip is near the first location. A post is inserted in the air hole into the gallery cavity. An electrolyte flow is directed through a first channel of the post to the gallery cavity and through a second channel of the post from the gallery cavity. A voltage potential is applied between the first electrode and the workpiece to remove burrs previously formed at the first location.

Abstract: In the electrochemical drilling of a hole completely through a workpiece, the present invention proposes operating the power supply in a current regulating mode. Initially, a hollow cathode is positioned adjacent to a workpiece in which one or more holes are to be drilled. An electrolyte is flowed through the cathode and against the workpiece. A constant electrical current is applied between the cathode and the workpiece across the electrolyte. Then the cathode is advanced at a constant rate toward the workpiece for the drilling of the hole(s), while maintaining the electrolyte flow and current substantially constant.

Abstract: Fabrication and use of porous silicon structures to increase surface area of heated reaction chambers, electrophoresis devices, and thermopneumatic sensor-actuators, chemical preconcentrates, and filtering or control flow devices. In particular, such high surface area or specific pore size porous silicon structures will be useful in significantly augmenting the adsorption, vaporization, desorption, condensation and flow of liquids and gasses in applications that use such processes on a miniature scale. Examples that will benefit from a high surface area, porous silicon structure include sample preconcentrators that are designed to adsorb and subsequently desorb specific chemical species from a sample background; chemical reaction chambers with enhanced surface reaction rates; and sensor-actuator chamber devices with increased pressure for thermopneumatic actuation of integrated membranes.

Abstract: In a metal honeycomb extrusion die which incorporates apertures for the conveyance of extrudable material through the die body toward a discharge opening in the face of the die, the aperture sidewalls are shaped by electrochemical machining or the like to develop a periodically varying aperture size, surface shape or surface finish, superimposed on the conventional randomly varying machined aperture sidewall surface, in order to reduce the adverse effects of random surface variations on extrusion process stability and extruded product quality.

Abstract: An element with elongated, high aspect ratio channels such as microchannel plate is fabricated by electrochemical etching of a p-type silicon element in a electrolyte to form channels extending through the element. The electrolyte may be an aqueous electrolyte. For use as a microchannel plate, the; the silicon surfaces of the channels can be converted to insulating silicon dioxide, and a dynode material with a high electron emissivity can be deposited onto the insulating surfaces of the channels. New dynode materials are also disclosed.

Abstract: The present invention provides a method for forming porous silicon, which includes the steps of: a) providing a silicon substrate; b) growing a GaAs layer on the silicon substrate; c) defining a pattern for the GaAs layer by a photolithography process and etching the patterned GaAs layer to obtain a GaAs mask; and d) forming a porous silicon layer by anodic-oxidation-etching the silicon substrate uncovered by the GaAs mask. By this method, etching under the GaAs layer on the silicon substrate can be executed very well to form the porous silicon. And the patterned GaAs layer is etched by a process in step c), which is selected from a wet etching and a dry etching process with a photoresist as a mask. In addition, the anodic-oxidation-etching process in step d) is an electrolytic process executed in HF acidic solution which is a mixture of 30 vol. % HF and 70 vol. % H.sub.2 O, in which the HF concentration is 49 wt. %.

Abstract: A process for producing a structured area of porous silicon on a substrate, in which silicon is etched and structured by means of illumination, includes selectively aiming the illumination during or after the formation of the porous silicon directly at a selected area of a p-doped substrate in order to effect etching and structuring of the porous silicon in another area. A device for carrying out the process includes an illuminating system for supporting the etching process and for structuring the porous silicon, in which the illuminating system is selectively aimed during or after the formation of the porous silicon directly at a selected area of p-doped substrate in order to effect etching and structuring of the porous silicon in another area.

Abstract: The invention relates to a method of forming one or more through-holes in a metal workpiece, such as shaving foils or shaving combs, by means of an electrochemical machining apparatus (ECM apparatus). To this end, the method is characterized in that, during machining, the workpiece is provided on a substrate of an electroconductive, electrochemically inert material, such as a noble metal (alloy), in particular a noble metal (alloy) which is predominantly composed of Pt. Preferably, the workpiece is clamped onto the substrate. By virtue of said measures, rounding of the edges between the holes formed and the surface of the workpiece, which is clamped down on the substrate during machining, is reduced substantially. This has a favorable effect on the formation of sharp cutting faces.

Abstract: Honeycomb extrusion dies for the extrusion of honeycomb ceramics of high cell density and reduced cell wall thickness are machined from fully consolidated powder-formed (P/M) stainless steels, providing dies with reduced feed hole roughness, improved feed hole straightness, and superior discharge slot finish, with the result that significantly enhanced extrusion performance and higher quality honeycomb extrusions are realized.

Abstract: The present invention teaches a method of producing a textured surface upon an arbitrarily configured titanium or titanium alloy object for the purpose of improving bonding between the object and other materials such as polymer matrix composites and/or human bone for the direct in-growth of orthopaedic implants. The titanium or titanium alloy object is placed in an electrolytic cell having an ultrasonically agitated solution of sodium chloride therein whereby a pattern of uniform "pock mark" like pores or cavities are produced upon the object's surface. The process is very cost effective compared to other methods of producing rough surfaces on titanium and titanium, alloy components. The surface textures produced by the present invention are etched directly into the parent metal at discrete sites separated by areas unaffected by the etching process. Bonding materials to such surface textures on titanium or titanium alloy can thus support a shear load even if adhesion of the bonding material is poor.

Abstract: Electrochemical machining (ECM) techniques utilizing real-time parameter monitoring, alarms and feedback control for improved machining of a workpiece are disclosed. The ECM device utilizes one or more cathodes, an electrolyte and a positively charged workpiece to achieve electrolytic action. A number of controlling variables, such as cathode feed rate, electrolyte flow rate and voltage, are balanced in response to measured system parameters. The following parameters are preferably monitored in order to adjust the controlling variables: the drive parameters of feed rate and cathode depth; the pump parameters of flow rate and pressure; and the power components of voltage and current. The flow rate in each of the cathodes, or a corresponding Reynolds number, is preferably utilized to provide an alarm to the operator if a statistically significant change in flow is detected.

Abstract: A halogenated polymeric material is exposed to a reducing agent and/or an electrolyte and applied voltage to render exposed portions capable of being metallized and of being etched. The exposed portions can also be doped to thereby induce electrical conductivity therein. Also, new structures containing a free standing halogenated polymeric-containing layer and electrical conductive pattern thereon are provided.

Abstract: The invention relates to a method of providing one or more through-holes in a metal workpiece by means of an electrochemical machining apparatus (ECM apparatus). Said method is characterized in that the surface of the workpiece from which the electrode of the ECM apparatus emerges is provided with an auxiliary layer, which comprises a polymeric network composed of organic and inorganic fragments. In this manner, rounding at the boundary between the holes formed and the exit surface of the ECM electrode is precluded. A polymeric network comprising silicon oxide and zirconium oxide as well as carbon-containing fragments, which are incorporated in the polymeric network via SiC bonds, are preferred.The invention can very advantageously be used to manufacture shaving foils and shaving combs.

Abstract: A heat generating type ink-jet print head including an ink supply passage for receiving an ink from an ink container, a micro chamber for storing the ink and nozzles, all being directly formed on a substrate, and a method for fabricating the ink-jet print head using an electrolytic polishing process, and a method for fabricating the ink-jet print head. The ink-jet print head is fabricated using an electrolytic polishing process, thereby achieving an accurate and inexpensive fabrication.

Abstract: A method of manufacturing an extrusion die for extruding a honeycomb structural body is disclosed. The extrusion die has a plurality of forming channels which have a shape in a traverse cross section corresponding to that of the honeycomb structural body and have a predetermined depth from a front side of the extrusion die toward a back side, and a plurality of opening holes for feeding raw materials which have a cylindrical shape extending independently from the back side toward the front side and are arranged at a cross portion and/or a straight portion of the forming channels in such a manner that each opening hole is opened and connected to the cross portion and/or straight portion of the forming channels.

Abstract: A method and apparatus for forming a passage with a variable diameter along its length in a conductive workpiece are disclosed. The workpiece is mounted in a fixture and an externally insulated hollow electrode is positioned proximate to a surface location of the workpiece into which the passage is to be formed. A first selected voltage is connected between the electrode and the workplace with the voltage being connected to cause the electrode to act as a cathode and the workpiece to act as an anode. A pump causes an acidic electrolyte to flow through the electrode at a chosen pressure and onto the workpiece surface. The electrode is moved toward the workpiece at a first selected feed rate by a CNC controller to cause a portion of the passage to be formed at a first predetermined diameter.

Abstract: A sensor arrangement having a substrate of doped silicon with channels in a principal face, a selective means for detecting a material, the selective means covering the principal face without filling the channels, and a measuring instrument for registering a physical quantity dependent on the influence of a material is provided. A catalytic layer is particularly used as selective means and a temperature sensor is particularly used as measuring instrument. Alternatively, the sensor arrangement is fashioned as a capacitor having a porous cooperating electrode. The channels are preferably produced by electrochemical etching.

Abstract: An electrode for use in a rotary electrical discharge machining (EDM) device for producing at least one curved hole in an article includes at least one curved tooth. The curved tooth lies in a plane. A perpendicular line to that plane is parallel to the axis of rotation on the rotary EDM device. At least one curved cooling hole is machined in the article.

Abstract: The present invention provides a method for treating a ceramic body to provide a wettable surface on the ceramic body. According to the present invention, a ceramic body is immersed in an alkaline hydroxide solution. The ceramic body is connected to form the anode and a suitable metal is connected to form the cathode of an electrolytic cell. A difference in electrical potential is imposed across the electrolytic cell which is sufficient to remove portions of the ceramic body to provide a pitted surface on the ceramic body which is wettable.

Abstract: Disclosed are electropolishing methods for etching a substrate in self alignment. A hole is formed in a substrate in self alignment by using an electropolishing system, wherein a reaction tube, an etchant solution, an electrode, a constant current source and the silicon substrate, said etchant solution being contained in a space confined by the reaction tube and the substrate, which is attached to one end of the reaction tube in such a way that the bottom of the substrate may be toward the interior of the space, said constant current source being connected with a metal layer formed on the substrate and the electrode. The substrate is made to be porous by flowing a constant current and etched by the action of the etchant solution while breaking the current. In addition to being economical, the methods can determine the position and size of the hole accurately and precisely. Further, neither chemical damage nor mechanical impact is generated on the substrate.

Abstract: A method used in manufacturing a cubically integrated circuit arrangement. A silicon wafer, wherein through pores are produced by electrochemical etching are insulated from the silicon wafer, and are provided with conductive fills, is secured as a carrier plate (24) to a substrate (21) that has components and that is integrated in a cubically integrated circuit arrangement. Terminal pads (25) that are electrically connected to conductive fills and that are arranged on the surface of the carrier plate (24) thereby meet contacts (23) to the components that are arranged at the surface of the substrate (21) adjoining the carrier plate (24) and that are firmly connected thereto.

Abstract: A process is set forth for electrochemically machining holes in a workpiece, such as a die, in such a manner so as to virtually eliminate surface finish patterns normally introduced by the electrochemical machining process, by randomly forming sequences of patterns of holes extending in rows across the workpiece along its extent, and then rotating the workpiece 180.degree. and randomly forming additional sequences of patterns of holes across the workpiece adjacent those sequences of holes which were formed prior to rotating the workpiece 180.degree..