Abstract: Electrochemical Fabrication techniques are used to modify substrates or to form multilayer structures (e.g. components or devices) from a plurality of overlaying and adhered layers. Masks are used to selectively etch or deposit material. Some masks may be of the contact type and may be formed of multiple materials some of which may be support materials, some of which may be mating materials for contacting a substrate and some may be intermediate materials. In some embodiments the contact masks may have conformable contact surfaces (i.e. surfaces with sufficient flexibility or deformability that they can substantially conform to surface of the substrate to form a seal with it) or they may have semi-rigid or even rigid surfaces. In embodiments where masks are used for selective deposition operations, etching operations may be performed after deposition to remove flash deposits (thin undesired deposits from areas that were intended to be masked).

Abstract: Treatment of substrates, formation of structures, and formation of multilayer structures using contact masks are disclosed where a non-parallel or non-simultaneous mating of various mask contact surfaces to a substrate surface occurs. Some embodiments involve bringing a relative planar mask contact surface and a relative planar substrate surface together at a small angle (but larger than an alignment tolerance associated with the system). Some embodiments involve flexing a mask to make it non-planar and bringing it into contact with a substrate such that progressively more contact between the mask and substrate occur until complete mating is achieved. Some embodiments involve use of gas or liquid pressure to bow a flexible or semi-flexible mask and use a linear actuator to bring the mating surfaces together and to bring the mask into a more planar configuration.

Abstract: A highly accurate, efficient, and non-mechanical method of removing material from the surface of a golf club head using the principles of electrolysis. The process generally includes positioning at least one electrode in close proximity to a portion of a rear surface of a striking plate, flowing a liquid containing an electrolyte between the rear surface portion and the electrode, and applying a low voltage between the rear surface portion and the electrode. The electrode has an overall negative charge and the golf club head has an overall positive charge, such that a pulsed high-density DC current passes between the electrode and the rear surface portion. This results in negatively charged electrolytes in the liquid attracting positively charged molecules of the rear surface portion, such that the designated amount of material from the rear surface portion is removed by electro-chemical oxidation and carried away by the liquid flow.

Abstract: Devices for enhancing the sensitivity of a microsensor or any other micro device by providing on-line preconcentration. Microconcentrators that can be integrated with a sensor or a micromachined GC to enhance the signal to noise ratio can include a miniaturized sorbent trap fabricated on a microchip. The microconcentrator can be made on a silicon substrate so that a sensor can be integrated on the same chip. The microconcentrator is composed of at least one microchannel lined with a microheater for in-situ heating. Preconcentration may be achieved on a thin-film polymeric layer deposited above the heater in the microchannel. Rapid heating by the channel heater generates a “desorption pulse” to be injected into a detector or a sensor.

Abstract: The present invention provides a method for indirect-electrification-type continuous electrolytic etching of a metal strip suitable for producing a low-core-loss, grain-oriented silicon steel sheet not susceptible to the deterioration of core loss after stress-relief annealing, and an apparatus for the indirect-electrification-type continuous electrolytic etching.

Abstract: A method and associated structure for increasing the rate at which a chromium volume is etched when the chromium body is contacted by an acid solution such as hydrochloric acid. The etch rate is increased by a metallic or steel body in continuous electrical contact with the chromium volume, both of which are in continuous contact with the acid solution. At a temperature between about 21° C. and about 52° C., and a hydrochloric acid concentration (molarity) between about 1.2 M and about 2.4 M, the etch rate is at least a factor of about two greater than an etch rate that would occur in an absence of the steel body. In one embodiment, the chromium volume is a chromium layer that rests upon a conductive layer that includes a metal such as copper, wherein the acid solution is not in contact with the conductive layer.

Abstract: The present invention is directed to a method of creating porous anode foil for use in multiple anode stack configuration electrolytic capacitors, producing a pore structure that is microscopic in pore diameter and spacing, allowing for increased energy density with a minimal increase in ESR. Initially, an anode metal foil is etched, according to a conventional etch process, to produce an enlargement of surface area. The etched foil is then placed into the electrochemical drilling solution of the present invention. Alternatively, the etched foil may be masked, so that only small areas of the etched foil are exposed, prior to being placed in the electrochemical drilling solution. A DC power supply is used to electrochemically etch the masked or unmasked foil in the electrochemical drilling solution of the present invention such that pores on the order of a few microns diameter are produced through the foil.

Abstract: An electrochemical etching system has an etching bath for holding an n-type silicon substrate with a first surface of the substrate in contact with hydrofluoric acid, an electrode positioned in the hydrofluoric acid, a power source having a positive pole connected to the silicon substrate and a negative pole connected to the electrode, and an illumination unit having a light source for illumination of a second surface of the silicon substrate. The illumination unit illuminates the second surface of the silicon substrate with an illumination intensity of 10 m W/cm2 or more. A ratio of a maximum illumination to a minimum illumination of the second surface of the silicon substrate is 1.69:1 or less. With the etching system, pores and/or trenches of a certain size and shape can be formed in an entire area of the silicon substrate having a diameter of more than three inches.

Abstract: A structural body material layer is formed directly on a base substrate or via a sacrificing layer or a peeling layer, a groove is fabricated electrochemically along an outer configuration shape of a part constituting an object at the structural body material layer and thereafter, only the sacrificing layer or the base substrate is selectively removed or the part is mechanically separated from the peeling layer to thereby separate the part and the base substrate and provide the part constituting the object or fabricate a part having a movable portion by partially restricting a portion to be separated.

Abstract: A process for electrochemically etching a layer (11) with electric conduction properties, of the doped metal oxide type, on a transparent substrate (10) of the glass type, fitted with a mask capable of being removed after etching, and the process consisting in:

Abstract: The present invention is directed to a method of etching anode foil in a non-uniform manner which increases the overall capacitance gain of the foil while retaining foil strength. In particular, by using a mask to protect a mesh grid of the foil from further etching, a previously etched foil can be further etched, prior to the widening step. Alternatively, the mask may be used in the initial etch, eliminating the need for the second process. In effect the foil may be etched to a higher degree in select regions, leaving a web of more lightly etched foil defined by the mask to retain strength. According to the present invention, the foil is placed between two masks with a grid of openings which expose the foil in these areas to the etching solution. The exposed area can be as little as 10% of the total foil to as much as 95% of the total foil, preferably 30% to 70% of the total foil area.

Abstract: Embodiments of a polishing article for processing a substrate are provided. In one embodiment, a polishing article for processing a substrate comprises a fabric layer having a conductive layer disposed thereover. The conductive layer has an exposed surface adapted to polish a substrate. The fabric layer may be woven or non-woven. The conductive layer may be comprised of a soft material and, in one embodiment, the exposed surface may be planar.

Abstract: A method for production of a rotor for centrifugal compressor, wherein the said rotor is produced from a monolithic disc, which is provided with a central hole. The method consists of use, within an isolating medium, of at least one first electrode which has polarity opposite the polarity of the rotor, wherein the said first electrode operates starting from the outer diameter of the monolithic disc, in order to produce the blades and the cavities of the said rotor, and wherein the processing takes place with a continuous path, consisting of a first step of roughing, followed by a second step of finishing with a tool which has a shape similar to that of the electrode used for the first roughing step, in order to produce an accurate geometry of the blades.

Abstract: A method for producing a separator integrated with a gas flow channel of fuel cells efficiently at low costs without deteriorating processing accuracy and the like. A plane-facing electrode nozzle 30 is placed oppositely to the face to be processed, which is partially covered with a mask M, of base material B of a separator. While feeding electricity to the electrode nozzle 30 and the base material B of a separator, an electrolytic solution is injected and fed from the side of the electrode nozzle 30 to the face to be processed of the base material B from a direction that is almost perpendicular to the face. Thereby, the unmasked portion undergoes electrolytic etching with the electrolytic solution lying between the face to be processed and the electrode nozzle 30 to form recessed portions for making a gas flow channel.

Abstract: A method of enhancing heat transfer and cooling efficiency in a cooling passage includes forming a plurality of turbulator rings in the passage, the rings projecting inwardly, substantially perpendicular to a cooling flow direction in the passage; and using a patterned electrode, forming at least one gap in one or more of the turbulator rings, extending substantially parallel to the flow direction.

Abstract: In an electrochemical reactor used for electrochemical treatment of a substrate, for example, for electroplating or electropolishing the substrate, one or more of the surface area of a field-shaping shield, the shield's distance between the anode and cathode, and the shield's angular orientation is varied during electrochemical treatment to screen the applied field and to compensate for potential drop along the radius of a wafer. The shield establishes an inverse potential drop in the electrolytic fluid to overcome the resistance of a thin film of conductive metal on the wafer.

Abstract: A method for manufacturing a fluid bearing is provided. A mask member having at least two sets of grooves provided at least two places along an axial direction is affixed to an outer surface of an electrode section of a fluid bearing manufacturing tool. Each of the groove sets consists of multiple grooves in a shape corresponding to designed fluid bearing grooves on a work piece, such as, for example, a sleeve section of the fluid bearing. The fluid bearing manufacturing tool is inserted into a hole created in the work piece, wherein a power source for electrolytic machining is connected between the fluid bearing manufacturing tool and the work piece. An electrolytic solution between the manufacturing tool and the work piece is allowed to flow to form fluid bearing grooves on an inner surface of the work piece through electrolytic machining.

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 method for producing a separator in which a recessed gas path is formed. Depth fluctuations of the gas path can be reduced. The gas path having plural depths or gradation can be formed easily. An electrically conductive member 3, as a separator, and a processing electrode 16, having patterned electrode projections 20, are immersed in an electrolytic solution facing each other. Current is fed between member 3 and electrode 16 for electrolytic processing to dissolve the portion of the member 3 facing projections 20, thus forming a gas path 30 having a surface roughness Rz on this bottom surface 30e not larger than 1 &mgr;m.

Abstract: The present invention deposits a conductive material from an electrolyte solution to a predetermined area of a wafer. The steps that are used when making this application include applying the conductive material to the predetermined area of the wafer using an electrolyte solution disposed on a surface of the wafer, when the wafer is disposed between a cathode and an anode, and preventing accumulation of the conductive material to areas other than the predetermine area by mechanically polishing the other areas while the conductive material is being applied.

Abstract: An electrolytic etching method for etching treating an object to be etched by an electrochemical reaction through an electrolyte between the object to be etched and an etching electrode, where the contact angle of the electrolyte to the object to be etched is not more than 70°. This electrolytic etching method can etch the object in a non-contact manner, can reduce the cost, number of steps, and processing time, and can enhance the patterning accuracy.

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 porous layer produced from silicon, germanium or aluminum by applying a wedge-shaped mask to the surface of the layer and by controlled elecrochemical etching along the mask.

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: There is provided a method of patterning a substrate with an atomic mask having a mask substrate and first atoms adsorbed on the mask substrate, the first atoms forming a mask pattern having a one-atomic thickness, including the steps, in sequence, of (a) depositing adatoms over a surface of a substrate to be patterned, the adatoms having low reactivity with second atoms of which the substrate is composed, and (b) putting the atomic mask close to the substrate in such a distance that the first atoms make a chemical bond with the adatoms, so that adatoms located nearest to the first atoms are desorbed out of the substrate to form a pattern on the substrate, the pattern being defined as an area where none of the adatoms exists. In accordance with the above mentioned method, it is possible to form a pattern on the sub-nanometer or nanometer order with high accuracy and in a short period of time, and it is also possible to repeatedly form the same pattern by using the atomic mask.

Abstract: A method for producing a filter includes the steps of providing a blank of etchable semiconductor material having a first side and a second side and affixing a holding element to the blank. The holding element is chemically resistant to an etching solution. A current source is connected to the blank and at least one of the first and second sides of the blank is illuminated with light. The holding element and the blank are immersed in the etching solution until the first side of the blank is wetted so that the first side is etched electrochemically. The holding element is affixed to the blank such that contact areas between the holding element and the blank remain free of the etching solution.

Abstract: An electrode used as a tool in an electrochemical machining process to generate raised areas or ridges in the walls of a predrilled hole in an electrically conductive workpiece has an electrically conductive cylinder partially coated with an electrically insulating material in a pattern defining the raised areas to be formed. The pattern may comprise a plurality of spaced apart rings. An electrochemical machining method of drilling bulbs in the walls of a predrilled hole uses the electrode of the invention to greatly increase process efficiency.

Abstract: Provided is an electrolytic etching method for etching treating an object to be etched by an electrochemical reaction through an electrolyte between the object to be etched and an etching electrode, wherein the contact angle of the electrolyte to the object to be etched is not more than 70°. Thus provided is an electrolytic etching method that can etch the object in a non-contact manner, that can reduce the cost, the number of steps, and the processing time, and that can enhance the patterning accuracy.

Abstract: An apparatus and method for electrochemically machining a texture on a metal bearing component. A ribbon is provided between an electrode and the metal bearing component. The ribbon is flexible, substantially non-conductive and provided with holes. While the ribbon is in direct contact with the metal bearing component, current is passed between the electrode and the metal bearing component. The pattern of the holes in the ribbon determines the pattern electrochemically machined on the surface of the metal bearing component. According to a preferred embodiment the ribbon is an endless belt.

Abstract: This present invention is directed to a method of etching anodic foil for electrolytic capacitors and provides a method of electrolytically growing a porous oxide mask on a surface of a high purity etchable strip of anodic foil for forming etch tunnels at strategic locations on the foil. Unetched high purity aluminum foil is placed in a prepared electrolyte doped with chloride. By passing current through the foil, a porous oxide mask is formed on the surface of the anode foil, with an optimized pore spacing. This oxide mask is then partially removed with a stripping agent in order to expose the underlying anode foil at the bottom of the mask pores to the etch solution. The mask is not removed completely, and the anode foil is exposed only at the pore sites. The foil can then be etched using a conventional etch solution. Etch pits and tunnels form only at the pore sites.

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 manufacturing line including a plurality of processing sections disposed in a series for manufacturing multi-layered printed circuit boards by continuously conveying and processing boards through the plurality of processing sections, in which the plurality of processing sections have at least two specific processing sections for conducting a common type of processes, and the specific processing sections are disposed in a common area.

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: A method for preforming electrochemical processes requiring the application of electricity on features of a substrate includes shorting out the features using a shorting layer across connectors to which the features a in electrical communication. Electricity is then applied and the process is performed.

Abstract: A method of removing a metallic erosion shield secured by a layer of non-metallic adhesive to a leading edge structure of a helicopter rotor blade comprising, the step of providing an electric field between the metallic component and an electrode, in the presence of an electrolyte between the metallic component and the electrode whereby the erosion shield is removed by an electrochemical process.

Abstract: A method, apparatus and system for fabricating a stencil mask for ion beam and electron beam lithography are provided. The stencil mask includes a silicon substrate, a membrane formed from the substrate, and a mask pattern formed by through openings in the membrane. The method includes defining the mask pattern and membrane area using semiconductor fabrication processes, and then forming the membrane by back side etching the substrate. The apparatus is configured to electrochemically wet etch the substrate, and to equalize pressure on either side of the substrate during the etch process. The system includes an ion implanter for defining a membrane area on the substrate, optical or e-beam pattern generators for patterning various masks on the substrate, a reactive ion etcher for etching the mask pattern in the substrate, and the apparatus for etching the back side of the substrate.

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: The invention shows a surface (2) for a metal implant (1) which has a coarse structure of elevations (3) and depressions (4), with the surface (2) being permeated by a network (5) of protruding ribs which form nodes (7) and interstices or meshes (8) having an interstice width of 2 mm to 0.4 mm, while the depressions represent sections of spherical cavities (11). The nodes (7) of the ribs can protrude the furthest like mountain peaks, whereas the ribs (6) which connect two nodes (7) each form a lower lying saddle (10) if the spherical cavities penetrate one another slightly. Through coating with an electrochemically resistant protective lacquer, into which holes can be shot at a predetermined spacing without damaging the metal, with a laser for example, a coarsely structured intermediary surface can be economically provided by means of electrochemical erosion which receives a fine structure through sand blasting.

Abstract: A method for producing a microfluidic coupler includes the step of producing a first mask on a top surface of a wafer. The first mask defines an insertion channel pattern selected to correspond to the cross sectional shape of a capillary. The wafer is etched through the first mask to form an insertion channel. A second mask is produced on a bottom surface of the wafer. The second mask defines a subchannel pattern selected to match the diameter of the bore of the capillary. The wafer is etched through the second mask to form a subchannel connected to the insertion channel. The capillary is inserted into the insertion channel such that the capillary is in fluid communication with the subchannel. In one embodiment, a capillary guide is secured to the wafer to facilitate insertion of the capillary into the insertion channel. The capillary guide has a tapered guide channel aligned with the insertion channel for guiding the capillary into the insertion channel.

Abstract: Wastewater containing a surfactant and an oil content that has been emulsified by the action of the surfactant can be freed of the oil content by a method including feeding the wastewater into the anode compartment, for electrolysis, of a diaphragm electrolyzer having an anode and a cathode provided in the anode compartment and a cathode compartment, respectively, which are spaced apart by a porous diaphragm and which are supplied with a dc voltage between the anode and the cathode, passing part of the electrolyzed wastewater through the diaphragm so that it enters the cathode compartment, discharging the influent from the cathode compartment, discharging the remainder of the electrolyzed wastewater from the anode compartment and introducing the same into the intermediate portion of a gas-liquid separator, withdrawing part of the influent from the top of the gas-liquid separator and introducing the same into a layer packed with an adhering material, where it is brought into contact with the adhering material,

Abstract: The present invention relates to a process for producing a surface structure, preferably on a cylinder, cylinder dressing, or roller of a printing machine, with a hard chromium coating which is galvanically produced and preferably ground to dimensional accuracy. The object of the invention is to develop a process which permits a surface structure to be produced on the hard chromium coating, which surface structure permits relatively high frictional forces between the contact points of the printing material and the coating of the cylinder of the printing machine. This is achieved in that the surface structure is produced in two process steps in sequence, a surface part structure being produced as a dot screen in an approximately even random distribution by means of a first material erosion process in a first process step, and the final surface structure being produced in a second process step by means of a second material erosion including the dot screen.

Abstract: A method of processing semiconductor films and layers, especially Group III Nitride films, has been achieved, using laser-enhanced, room-temperature wet etching with dilute etchants. Etch rates of a few hundred .ANG./min up to a few thousand .ANG./min have been achieved for unintentionally doped n-type Group III Nitride films grown by MOCVD on a sapphire substrate. The etching is thought to take place photoelectrochemically with holes and electrons generated by incident illumination from 4.5 mW of HeCd laser power enhancing the oxidation and reduction reactions in an electrochemical cell.

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: An electrically conductive substrate (20) is etched by providing an etchant solution having finely divided, electrically conductive particles (40) mixed therein. The electrically conductive particles (40) are made of a material that is cathodic to the substrate (20) and does not dissolve into the etchant solution, with a preferred such material being graphite. The substrate (20) is placed into the etchant solution having the particles (40) therein so that the particles (40) contact the substrate (20), and etched for a period of time sufficient to remove a desired amount of the substrate material. The substrate (20) may be provided with an apertured mask (24) prior to being placed into the etchant solution.

Abstract: A method for manufacturing a porous blue light emitting diode comprising the steps of preparing a silicon substrate having a back surface, applying a conducting layer on the back surface, annealing the substrate coated with the conducting layer in an inert gas atmosphere, applying an anti-corrosion layer on the conducting layer, immersing the anti-corrosion layer-applied substrate in a hydrofluoric acid aqueous solution with a concentration of about 5% by volume, applying a voltage to the resulting layers for eroding the anti-corrosion layer-applied substrate to form a porous layer having Si wires on a top surface of the substrate, and oxidizing the porous layer for making sizes of the Si wires small enough for emitting light having a peak occuring at a wavelength shorter than about 520 nm. This method offers a simple and feasible way to fabricate a porous blue light emitting diode.

Abstract: A one piece electrode is disclosed for use in miniature and subminiature lamps having a large diameter post section and a smaller diameter lead-in section. The lead-in section is formed by an electrochemical process from a wire that has an outer diameter equal to the desired post diameter. A smooth evenly tapered transition section between the post and lead-in sections is created during the etching process which permits heat to pass through the electrode at a controlled and predictable rate.

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: According to this process a structure is produced comprising an insulating substrate (10) carrying at least one cathode conductor (12), an insulating layer (14), a gate layer (16), holes being formed through these layers, level with the cathode conductor. In the holes are formed microtips made from a metallic material by forming a protective insulating layer (50) on the gate layer, forming a chemical deposit (60) of the metallic material at the bottom of the holes until said material overflows therefrom, by eliminating the protective layer and by electrolytically etching the metallic material. Application to the manufacture of flat screens.

Abstract: An electroetching tool using scanned localized application of flowing electrolyte against a workpiece such as a large area mask having high density features for the fabrication of microelectronic components. A masked molybdenum plate is suspended in a vertical direction within a tank which functions as a reservoir for a recirculating electrobyte. The electrolyte in the reservoir is filtered and pumped to a pair of travelling cathode assemblies from which the flowing electrolyte is simultaneously applied through respective charged orifices to both sides of the workpiece. The workpiece is masked on its opposite sides with mirror imaged mask apertures having corresponding opposite-sided features in registration with each other.Each orifice through which the electrolyte is applied comprises an open groove in the surface of a block of polyvinal chloride material which groove extends in a vertical direction relative to the tank. The bottom of the groove is adjacent to a conductive plate.

Abstract: In through-mask electroetching of a metal film on top of an insulating substrate, the shape of the metal film being etched is a function of the mask opening, the spacing between the openings and the thickness of the mask. An analysis of the electric field around the mask and the metal film is used to determine conditions leading to the formation of islands of unetched metal films within the openings. The analysis is then used to design the mask pattern and eliminate these islands. The increase in the ratio of the mask thickness to the opening width for eliminating the islands also lowers the undercutting of the mask. Premature stoppage of the electroetching process arising from the isolation of the sample film from the contact is also addressed. The electrical contact to the sample is made at one end and a nozzle jet of electrolyte is slowly swept from the far end of the sample towards the electrical contact.