Abstract: A semiconductor device having a non-doped polysilicon and a doped polysilicon containing group III element is selectively wet-etched the non-doped polysilicon by using an etching liquid. The etching liquid is an electrolytic liquid obtained on a side of a cathode electrode and the electrolytic liquid is formed by electrolyzing a liquid containing pure water added with ammonium ion.

Abstract: An electrochemical procedure is employed to selectively remove certain material from a structure without significantly electrochemically attacking other material of the same chemical type as the removed material. The material to be removed constitutes part or all of an electrically non-insulating region (52C). The material which is of the same chemical type as the removed material but which is not to be significantly electrochemically attacked during the removal procedure constitutes part or all of another electrically non-insulating region (52A) electrically decoupled from the first-mentioned non-insulating region. The electrochemical removal procedure is performed with an organically based electrolytic solution containing organic solvent and acid.

Abstract: A method of machining metal-matrix composite materials using electrochemical machining is provided. The method comprises the steps of: providing a metal matrix composite material in an electrochemical machine, and electrochemically machining the metal-matrix composite material in a nitrate or chloride containing electrolyte at a current density of equal to or greater than approximately 1 A/cm.sup.2. Preferably the metal-matrix composite is comprised of an aluminum alloy or pure Al matrix with ceramic particles, such as silicon carbide.

Abstract: The present invention provides a method of manufacturing a superhard article with diamond coat having an excellent resistance against breakaway or peeling off of its coat, in particular, a cutting tool. A carbide base material formed to a desired shape containing tungsten carbide (WC) as a main component is soaked in a solution of alkali chloride and undergoes electrolytic etching on the surface of the base material at a maximum removal speed of 0.2 to 1.5 .mu.m/min for 3 to 30 minutes and, after the surface of the base material is washed, a diamond coat is developed on the surface of the base material by vapor deposition.

Abstract: A method for selectively wet etching material during the formation of a field emission display device. In one embodiment, the selective wet etching method comprises immersing, in a fluid bath, a structure having a conductive row layer and a resistor layer. The structure further includes a pad area. In this embodiment, the fluid bath includes an organic-acid etchant. The present embodiment then applies a potential to the structure such that exposed regions of the resistor layer are selectively wet etched without significantly etching the conductive row layer or the pad area. In so doing, the present embodiment etches selected materials without requiring the use of highly toxic and hazardous conventional etchants.

Abstract: A method is provided for photochemical polishing of a silicon wafer using electromagnetic waves within the spectrum of 150 to 2000 nanometers wavelength. A photochemical polishing apparatus is also disclosed in which the electromagnetic waves are provided by a waveguide in close proximity to the surface of a silicon wafer electrode.

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: An electrode structure is constituted by a first electrode, and at least one second electrode providing a pair of opposite portions with a prescribed spacing therebetween at which the first electrode is disposed. The electrode structure is suitably used for electrolytic etching and is effective in providing an accurate etching pattern without damaging the surface of an etching object.

Abstract: A method of three-dimensionally microcutting a metal material suitable for molds is provided. An electrolyte is interposed between a work piece which is made of a conductive material, and an electrode. Through application of an electrolysis voltage between the work piece and the electrode with the electrolyte interposed between them, a passive state film is formed on the surface of a to-be-cut part of the work piece. Then, the passive state film on the surface of the to-be-cut part of the work piece is cut.

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: The present invention relates to a method for polishing coated cutting tools and wear parts, where at least the outer layer of the coating consists of TiN, TiC or Ti(C,N), to a high surface finish. An electrolytic method is used with an electrolyte consisting of perchloric (HClO.sub.4) or sulphuric (H.sub.2 SO.sub.4) acid, 2-50 volume %, in methanol or other organic liquid. The method is easier to control than conventional mechanical methods and renders a high surface finish over the whole coated part.

Abstract: The present invention provides for a wet etch and method for preparing a semiconductor device structure from a silicon carbide wafer. A first embodiment of the wet etch comprises a vessel, a tetrahydrofurfuryl alcohol and potassium nitrite etching solution within the vessel, an electrode, a wafer support for positioning at least a portion of the silicon carbide wafer within the etching solution, and a voltage source coupled with the electrode and the wafer support. A second embodiment of the wet etch comprises a wafer carrier for holding at least one wafer, a polishing plate adjacent the wafer carrier, a voltage source having a first terminal electrically coupled with the wafer and a second terminal electrically coupled with the polishing plate, and an applicator adjacent the polishing plate for depositing an etching solution on a surface of the polishing plate.

Abstract: An electrochemical cell for etching a metal workpiece such as an aluminum foil, a method for etching the foil using the electrochemical cell, and foil thus produced is provided. The cell includes an etch tank having an etch electrolyte disposed therein and containing at least a first and a second compartment each containing (i)an etch electrolyte, (ii) a cathode plate, and (iii) an ion exchange membrane separator portion having an ion exchange polymeric material effective to substantially retard or prevent reduction of the oxidizing agent or agents present in the etch electrolyte, the first and second compartments being arranged in the etch tank with the ion exchange membrane separator portions in facing relationship one to the other; and a metal workpiece such as an aluminum foil anode present in the etch tank and disposed between each said first and second compartments.

Abstract: An impedance-assisted electrochemical method is employed for selectively removing certain material from a structure without significantly electrochemically removing certain other material of the same chemical type as the removed material.

Abstract: A method for sharpening field emitter tips by electroetching/polishing. In gated field emitters, it is very important to initiate electron emission at the lowest possible voltage and thus the composition of the emitter and the gate, as well as the emitter-gate structure, are important factors. This method of sharpening the emitter tips uses the grid as a counter electrode in electroetching of the emitters, which can produce extremely sharp emitter tips as well as remove asperities and other imperfections in the emitters, each in relation to the specific grid hole in which it resides. This has the effect of making emission more uniform among the emitters as well as lowering the turn-on voltage.

Abstract: The present invention provides an ink jet print head capable of fast, efficient and consistent printing. Such ink jet print heads include an ink ejecting component which incorporates electropolished surfaces. Electropolishing techniques useful in the production of such ink ejecting components are also discussed.

Abstract: A method for etching an object having a portion to be etched on the surface thereof, comprising a step of immersing said object in an electrolyte solution such that said object serves as a negative electrode; a step of arranging a counter electrode having a pattern corresponding to a desired etching pattern to be formed at said portion to be etched of said object in said electrolyte solution so as to maintain a predetermined interval between said counter electrode and said object, and a step of applying a direct current or a pulse current between said object and said counter electrode to etch said portion to be etched of said object into a pattern corresponding to said pattern of said counter electrode.

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: A method to improve the robustness of an elongated electrode used in an arc fusion apparatus for splicing optical fibers by reshaping the tip of the elongated electrode by electrolytic etching. The method involves reshaping the substantially sharp tip of the elongated electrode by immersing it as the anode in an electrolyte solution, the electrolyte solution is one capable of dissolving an oxidation product of the elongated electrode. Then a second electrode is provided at a predetermined distance from the elongated electrode in the electrolyte solution. Afterward, an electrical current is passed, or caused to flow, between the elongated electrode and the second electrode for a predetermined period of time through the electrolyte solution to reshape the substantially sharp tip of said elongated electrode into a predetermined profile having a substantially round tip.

Abstract: A silicon on-insulator device wafer having a very thin monocrystalline film with uniform thickness. It is fabricated by vias technique in which a monocrystalline silicon film on an insulator is etched with a base silicon etching solution in an etch apparatus by applying a vias in such a way that the solution may serve as an anode and the substrate of SOI structure as a cathode. The presence of the insulator generates vacancies in a lower region of the monocrystalline silicon film and electrons in the substrate, so that the lower region charged with the vacancies is not removed by the base silicon etching solution, thereby leaving a highly uniform, thin monocrystalline silicon film.

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 process for removing zinc from galvanized steel. The galvanized steel is immersed in an electrolyte containing at least about 15% by weight of sodium or potassium hydroxide and having a temperature of at least about 75.degree. C. and the zinc is galvanically corroded from the surface of the galvanized steel. The material serving as the cathode is principally a material having a standard electrode potential which is intermediate of the standard electrode potentials of zinc and cadmium in the electrochemical series.

Abstract: For a condensed matter system containing a guest interstitial species such as hydrogen or its isotopes dissolved in the condensed matter host lattice, the invention provides tuning of the molecular orbital degeneracy of the host lattice to enhance the anharmonicity of the dissolved guest sublattice to achieve a large anharmonic displacement amplitude and a correspondingly small distance of closest approach of the guest nuclei. The tuned electron molecular orbital topology of the host lattice creates an energy state giving rise to degenerate sublattice orbitals related to the second nearest neighbors of the guest bonding orbitals. Thus, it is the nuclei of the guest sublattice that are set in anharmonic motion as a result of the orbital topology. This promotion of second nearest neighbor bonding between sublattice nuclei leads to enhanced interaction between nuclei of the sublattice.

Abstract: An electrochemical technique is employed for removing certain material from a partially finished structure without significantly chemically attacking certain other material of the same chemical type as the removed material. The partially finished structure contains a first electrically non-insulating layer (52C) consisting at least partially of first material, typically excess emitter material that accumulates during the deposition of the emitter material to form electron-emissive elements (52A) in an electron emitter, that overlies an electrically insulating layer (44). An electrically non-insulating member, such as an electron-emissive element, consisting at least partially of the first material is situated at least partly in an opening (50) extending through the insulating layer.

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: An electrochemical cell for etching a metal workpiece such as an aluminum foil, a method for etching the foil using the electrochemical cell, and foil thus produced is provided. The cell includes an etch tank having an etch electrolyte disposed therein and containing at least a first and a second compartment each containing (i)an etch electrolyte, (ii) a cathode plate, and (iii) an ion exchange membrane separator portion comprising an ion exchange polymeric material effective to substantially retard or prevent reduction of the oxidizing agent or agents present in the etch electrolyte, the first and second compartments being arranged in the etch tank with the ion exchange membrane separator portions in facing relationship one to the other; and a metal workpiece such asan aluminum foil anode present in the etch tank and disposed between each said first and second compartments.

Abstract: Process of smoothing or polishing a diamond surface to reduce asperities reon to a level as low as about 20 nm from the horizontal by implanting the diamond surface with ions to form a non-diamond carbon damage layer on or below the diamond surface below the disparity depth and dissolving the non-diamond carbon by submerging the non-diamond carbon in a liquid having sufficient electric field to dissolve the non-diamond carbon.

Abstract: A fabrication method for a diamond-coated cemented carbide cutting tool includes electrolytically etching the surface of a cemented carbide cutting tool with a NaOH or KOH aqueous solution or chemically etching the surface of the cemented carbide cutting tool with a KMnO.sub.4 +KOH aqueous solution, and depositing a diamond film on the cemented carbide cutting tool. A stronger etching effect than by using a Murakami solution can be achieved, and no poisonous material is included in the etchant. In addition, disposal of the waste etchant is made simpler, and the adhesion between the diamond film coating and the cemented carbide cutting tool can be strengthened.

Abstract: The invention provides a method for producing semiconductor particles in which a semiconductor material of the type for which particles are desired is placed in an electrolytic solution of an anodic cell. The anodic cell is configured with a cathode also positioned in the electrolytic solution. The electrolytic solution of the anodic cell includes an etchant and a surfactant that is characterized by an attractive affinity for the semiconductor material. To produce semiconductor particles from the semiconductor material, an electrical potential is applied between the semiconductor material in the electrolytic solution and the cathode in the electrolytic solution to anodically etch the semiconductor material. During the etch process, particles of the semiconductor material form and are encapsulated by the surfactant. This method for producing semiconductor particles uses an uncomplicated apparatus and procedure that results in inexpensive and high-volume production of particles of a semiconductor material.

Abstract: A method of machining the surface of an electrically conductive workpiece by application of a voltage to an electrically conductive tool spaced apart from the workpiece and moving the tool to shape or pattern the workpiece wherein variable flow of fluid is provided in the space between the tool and the workpiece. The fluid contains suspended insoluble interactive particles that are electrically conductive or are ionically conductive, but electronically insulating. The suspended particles came intermittent electrical short circuiting between the tool and the workpiece to prevent catastrophic and uncontrolled sparking or arcing during machining.

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: A carbide substrate including a binder prepared to receive a cutting material such as a diamond coating thereon. The substrate is immersed in an electrolyte solution with the substrate acting as the anode thereby providing for an electro-polished substrate surface. The electro-polished substrate surface is then etched to substantially remove the binder phase of the carbide substrate, the etching being to a depth of up to about 15 microns. The resulting surface is susceptible for receiving a coating of the diamond cutting material.

Abstract: A tip and substrate preparation system for use with scanning probe microscopes (SPMs) includes a scanning tunneling microscope (STM) tip maker, STM tip coater, a substrate treatment method for producing clean, flat gold substrates for STM use and methods for preparing chemically activated substrates for use with an atomic force microscope (AFM). The tip maker includes a coater and an etcher which are preferably controlled by electronic controllers. The etcher provides fully automatic tip etching in a two-stage process in sodium hydroxide (NaOH) solution, permitting platinum alloys to be etched without the use of cyanide-containing chemicals. The coater is used to insulate the tips with soft polymer coatings so as to ensure very low tip leakage current (on the order of about 1 pA typical). The substrate treatment device comprises a quartz plate and a quartz torch for annealing substrates in a hydrogen flame.

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: A high speed electrochemical metal removal technique provides for planarization of multilayer copper interconnection in thin film modules. The process uses a neutral salt solution, is compatible with the plating process and has minimum safety and waste disposal problems. The process offers tremendous cost advantages over previously employed micromilling techniques for planarization.

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: An object of the present invention is to offer a magnetic recording medium comprising a substrate and a magnetic film formed on the substrate, wherein the substrate is formed using a conductive material and a surface of said substrate is processed by electroetching. As this magnetic recording medium has excellent surface characteristics, excellent durability and small spacing loss, its recording and play back characteristics are excellent.

Abstract: A method of producing a support for a planographic printing plate which comprises roughening a surface of an aluminum plate electrochemically, etching the surface by 0.01 to 20 g/m.sup.2 with alkali, and roughening the surface electrochemically in an electrolytic solution containing hydrochloric acid and/or a water-soluble hydrochloride salt which forms hydrochloride ion or nitric acid and/or a water-soluble nitrate salt which forms nitrate ion as the principle component.

Abstract: Disclosed herein are methods of measuring, adjusting and uniformalizing a sectional area ratio of a metal-covered electric wire, a method of cleaning an electric wire, a method of manufacturing a metal-covered electric wire, an apparatus for measuring a sectional area ratio of a metal-covered electric wire, and an apparatus for electropolishing a metal-covered electric wire.Electric resistance values of first and second materials are previously stored respectively so that a sectional area ratio of a metal-covered electric wire is calculated on the basis of the as-stored values and an actually measured electric resistance value of the metal-covered electric wire. Measurement and uniformalization of a sectional area ratio of a metal-covered electric wire and cleaning of an electric wire are carried out by dissolving surface layer parts of the electric wires by electropolishing.

Abstract: A method of etching an aluminum foil for electrolytic capacitors, comprising the steps of electrolytically etching an aluminum foil for electrolytic capacitors that has a high cubic texture in an electrolyte containing a chloride to form pits, and enlarging the pits formed in the above step by etching, in which step of forming pits the current density is increased from 0 to a maximum value quickly and then is decreased gradually.

Abstract: A system for making porous silicon on blank and patterned Si substrates by "immersion scanning", particularly suitable for fabricating light-emitting Si devices and utilizing an open electrolytic cell having a cathode and an opposing anode consisting of a Si substrate on which the porous silicon is to be formed, both disposed, with their opposing surfaces in parallel, in an aqueous HF solution electrolyte contained in the cell. The substrate anode is mounted to be movable relative to the electrolyte so as to be mechanically cycled or scanned in and out of the electrolyte at a programmable rate during anodization. The uniformity, thickness and porosity of the resulting anodized layer on the substrate are determined by the scanning speed, number of cycles, current density, and HF-based electrolyte parameters of the system, and the Si substrate resistivity, conductivity type, and crystal orientation.

Abstract: The present invention relates to a method of etching aluminum foil for electrolytic capacitors that is improved in etching efficiency, wherein when the aluminum foil is etched by applying alternating current in an electrolytic solution containing chloride ions and the like, the alternating current contains, during the positive half period and the negative half period, two half waves having different waveforms, amplitudes, and applied times, and a rest period between the half waves with the amplitude being 0 or with microcurrent being applied on the positive side or the negative side at at most 1/15 of the maximum amplitude during a half period.