Abstract: A flexible and efficient bulk micromachining method for fabricating a novel microstructure that is bounded by substantially planar surfaces meeting only at substantially right angle corner features. The novel microstructure of the present invention is useful as a spacer in assembly processes where high accuracy is required, such as precise positioning of optical fibers or conductors. In the preferred embodiment, the microstructure of the present invention includes a shelf feature disposed along a height dimension of the microstructure, which is required for some applications. The bulk micromachining method of the present invention includes providing a first substrate having a top planar surface and an opposing planar surface. The opposing surface of the substrate is anisotropically etched to provide a first thinned region. The top surface of the first substrate is anisotropically etched so that a first recessed feature having a vertical side is made integral with the first thinned region.

Abstract: Semiconductor substrates are immersed in pure water having a lowered dissolved-oxygen concentration and heated to a temperature above 60.degree. C., in an atmosphere which keeps the dissolved oxygen concentration in pure water, in order to etch oxide films on surfaces of the semiconductor substrates for cleaning the surfaces of the semiconductor substrates. According to the present invention, contaminants and residual chemicals can be effectively removed without adding any chemical treating step. The cleaning can be effective without increasing the number of chemicals, and improved throughputs of the cleaning step can be obtained.

Abstract: A method of making a circuitized substrate wherein a dielectric layer is provided having a first layer of metallic material thereon. A first metallic member is formed on the dielectric's metallic layer, following which a pair of openings are precisely provided within a second dielectric material located on the dielectric. These openings in turn define a selected area on the first metallic member and, significantly, a precisely oriented pattern of the first metallic layer at a spaced distance from the metallic member. This metallic pattern serves as a mask to permit formation of an opening through the dielectric, which opening in turn may be engaged by tooling or the like such as may be used to position an electronic component, e.g., semiconductor device, on the underlying substrate.

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

Abstract: For producing a layer having reduced mechanical stresses, the layer is composed of at least two sub-layers that are matched to one another such that stress gradients in the two layers substantially compensate. The method is particularly employable in the manufacture of structures in surface micromechanics.

Abstract: This application describes a new method for rapid thinning, planarizing and fine polishing surfaces of diamond to the submicron/nanometer level so that large area, uniform thickness diamond wafers can be obtained. The method combines both chemical (dissolution of carbon in molten metals) and mechanical (rotating or moving sample fixtures in contact with the dissolving metals) polishing to achieve flat, smooth surface finishes in a relatively short period of time, thus improving the quality and economics of the overall polishing process. Several embodiments of apparatus for performing such chemical-mechanical polishing (CMP) of diamond are described.

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: This invention concerns a method of fabricating a surgical cutting tool and a tool fabricated by such method. The surgical cutting tool (20) comprises a base (21) and an upstanding cutting blade (22), fabricated by locating a mask (32) of a shape corresponding to that of the required cutting blade on the surface of a substrate (31) and etching the substrate from its exposed surface and undercutting the mask from the edges thereof to thereby for a cutting edge of an upstanding cutting blade (22) in the substrate under at least a part of the mask. The tool of the invention is particularly suitable for cutting thin membranes within the human or animal body and has specific application in extracapsular cataract extraction operations, where accurate cutting of the thin membrane of the eye's lens capsule is required.

Abstract: A system for processing a plurality of tests or syntheses in parallel comprising a sample channel for moving samples into a microlaboratory array of a plurality of wells connected by one or more channels for the testing-or synthesis of samples, a station for housing the array and an optical system comprising at least one light source and at least one light detector for measuring the samples in the array, and a means of electrically connecting said array to an apparatus capable of monitoring and controlling the flow of fluids into the array. Samples are loaded from a common loading channel into the array, processed in the wells and measurements taken by the optical system. The array can process many samples, or synthesize many compounds in parallel, reducing the time required for such processes. Etching from both sides of a substrate using patterned photoresist and metal layers to form a network of capillary channels for separately transporting a plurality of different liquids.

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

Abstract: The method of shaping a polycrystalline diamond (PCD) body (exemplarily a wafer of CVD-PCD) utilizes our discovery that the rate and amount of diamond removal from a given region of a PCD body depends, for a given metal "etchant" at a given temperature, on the thickness of the etchant layer overlying the given region, with relatively larger etchant thickness being associated with relatively higher removal rate and amount. Exemplarily, the method can be used to substantially remove thickness variations and/or film curvature from as-produced PCD films. An exemplary metal that can be used in the practice of the invention is mischmetal. The metal etchant can be molten, partially molten or solid.

Abstract: The invention is directed towards a wet chemical process for removing physical vapor deposited or air plasma sprayed thermal barrier coatings from coated parts without damaging or effecting the bond coat or the base metal substrate. The process entails using an autoclave with an organic caustic solution to fully remove the thermal barrier coating.

Abstract: The present invention is directed toward a method of removing epitaxial substrates from host substrates. A sacrificial release layer of ternary material is placed on the substrate. A layer of InP is then placed on the ternary material. Afterward a layer of wax is applied to the InP layer to apply compressive force and an etchant material is used to remove the sacrificial release layer.

Abstract: A method for producing a wall, roadway, sidewalk or floor of cementitious material having the appearance of natural stone and mortar including a base with an outer surface with a plurality of irregular shaped protrusions disposed in a random pattern to simulate natural stones and a plurality of simulated grout lines formed therebetween, the method including the steps of preparing a cementitious material, pouring the cementitious material into a form, vibrating the cementitious material, allowing the cementitious material to cure forming the base with the outer surface, releasing the base with the plurality of irregular shaped protrusions disposed in the random pattern to simulate natural stones and the plurality of simulated grout lines formed therebetween from the form, coloring the outer surface and accenting the plurality of simulated grout lines.

Abstract: An etching process is provided using electromagnetic radiation and a selected etchant (52) to selectively remove various types of materials (53) from a substrate (48). Contacts (49, 56, 64) may be formed to shield the masked regions (51) of the substrate (48) having an attached coating (20) during irradiation of the unmasked regions (53) of the substrate (48). The unmasked regions (53) are then exposed to an etchant (52) and irradiated to substantially increase their reactivity with the etchant (52) such that the etchant (52) etches the unmasked regions (53) substantially faster than the masked regions (51) and the contacts (49, 56, 64).

Abstract: A substrate free single crystal pyroelectric film particularly suited for use in rapid thermal response sensors is made from a single crystal substrate by a method including the steps of:(A) etching a pattern into the substrate;(B) epitaxially growing a highly oriented superconducting material into the etched pattern to fill the etched pattern,(C) epitaxially growing a highly oriented crystalline film of a pyroelectric material over the entire surface of the substrate, and(D) dissolving away the highly oriented superconducting material.

Abstract: The subject invention provides a method of enhancing the etch rate of boron nitride which comprises doping a layer of boron nitride with an element from Group IVA of the Periodic Table of the Elements, such as silicon, carbon, or germanium. The doped boron nitride layer can be wet etched at a faster rate with hot phosphoric acid than was possible prior to doping the boron nitride.

Abstract: A method of decorating concrete including the steps of mixing water, aggregate and cement to provide mortar, pouring the mortar into a form and allowing it to cure and harden into a concrete block having an exterior surface, and applying sulfate to a selected portion of the block to color the surface of the block to a predetermined depth while the mortar is being cured.

Abstract: A method of patterning a material surface is provided in which an elastomeric stamp having a stamping surface is coated with a self-assembled monolayer forming species having a functional group selected to bind to a particular material, and the stamping surface is placed against a surface of material and is removed to leave a self-assembled monolayer of the species according to the stamping surface pattern of the stamp. Additional stamping steps may be subsequently effected to produce any of a variety of SAM patterns on the surface. Additionally, portions of the material surface that are not coated with a stamped SAM pattern may be filled in with another SAM-forming species. Alternately, portions that are not covered by a SAM layer may be etched or plated. Additionally, an optical switch and other optical devices and elements are provided, comprising articles similar to the inventive stamp.

Abstract: A method is provided for preparation of a composite including steps of providing a preform and a liquid infiltrant alloy including at least two elements and having a liquid infiltrant alloy composition which is selected so that the liquid infiltrant alloy spontaneously infiltrates the preform and contacting the liquid infiltrant alloy with the preform so that a chemical reaction occurs to form a composite by reactive infiltration, as are composites produced according to the method of the invention.

Abstract: A diamond body, such as a CVD diamond film, is etched by immersion of the body in a molten or partially molten metal, such as the rare earth metal La or Ce. While the body is being etched, various portions of a major surface of the body can be protected for various time durations by masks against the etching--whereby, after dicing the body, the resulting dies can be used as submounts for lasers with feedback.