Abstract: A method of producing diamond crystal growth on a seed crystal is provided. The method includes the steps of providing a seed crystal containing at least one twin plane and re-entrant growth surfaces associated therewith and applying high temperature/high pressure synthesis conditions to the seed crystal to cause diamond growth to occur preferentially on the re-entrant surfaces. The diamond growth on the seed crystal results in a diamond crystal being produced which has an aspect ratio greater than 1.

Abstract: Diamonds are synthesized from SiC at temperatures and/or pressures lower than those required to convert amorphous carbon or graphite to diamond, by heating the SiC in the absence of another non-diamondaceous source of elemental carbon and in the presence of a reactant which selectively reacts with the Si at the temperature to which the SiC is heated, and in a matrix which is frangible when cooled, while the Sic is within the diamond stable region of the diamond-graphite phase diagram, thereby permitting the diamond to be separated therefrom by physical means.

Abstract: Diamond film with substantially no non-diamond carbon and a high thermal conductivity is deposited by means of a direct current arc jet apparatus with a substrate temperature below about 975 degrees Celsius, an arc power of between about 20 and 40 kw. a pressure of about 12 torr, and an enthalpy greater than 30 from a activated gas jet fed with hydrogen and methane, the methane being supplied at a concentration of less than 0.07%. The resulting material has a high transparency and thermal conductivity.Also disclosed is the use of the diamond material made by the present method for cutting tool applications, particularly milling.

Abstract: The present invention provides a method for coating a metal alloy component of a medical implant, particularly a component of a heart valve made of a titanium base alloy, with a strongly adhered coating of diamond-like carbon. The method uses ion beam assisted deposition to form a gradient at the surface of the titanium alloy comprising metal alloy/metal-silicide/(silicon or germanium)/silicon- or germanium-carbide/DLC.

Abstract: In a method for forming a diamond film by a high-frequency plasma CVD method, an inductive coupling discharge is used and the frequency of a high-frequency wave is set in the range of from 40 to 250 MHz, whereby a starting gas containing carbon is decomposed in a plasma state and a diamond film is formed on a substrate.

Abstract: A process for analyzing analytes using nebulizer component selected from the group consisting of a desolvation tube, a condenser tube, an aerosol-generator and a transducer, wherein the component has a contact surface selected from the group consisting of CVD silicon carbide, CVD diamond film and glassy carbon.

Abstract: A method for synthesizing large, single crystal diamond comprising mixing carbon source and a hydrogen source to form a mixture. The mixture is excited and reacted to form a reactive species in a laminar plasma plume. A substrate having a diamond seed crystal is disposed in the laminar plasma plume while maintaining the diamond seed crystal at a growth temperature between 1100.degree. and 1700.degree. C. for the deposition of diamond, thereby inducing deposition of single crystal diamond on the diamond seed crystal.An apparatus for synthesizing diamond (10;15) comprising a plasma torch (30;31) for producing a laminar plasma plume (44;54). A carbon source (CH.sub.4) and a hydrogen source (H.sub.2,CH.sub.4) are excited and reacted in the laminar plasma plume (44;54) so as to form a reactive species in the laminar plasma plume (44;54).

Abstract: Doped and undoped polycrystalline and noncrystalline diamond films produced by plasma enhanced chemical transport emit electrons into a vacuum in response to an applied electrical field. The field required to create emission is less than 20 V/.mu.m for doped polycrystalline films, can be in the range of 5 to 8 volts/.mu.m for undoped nanocrystalline films and may be 3 volts/.mu.m or less for doped nanocrystalline films. These materials exhibit emission properties which are continuous across the whole surface of the film.

Abstract: A method is proposed for growing diamond from graphite, including placing a sample of graphite in a high pressure chamber, applying a pulse-periodical laser radiation having a wavelength in the region of transmission of diamond to the sample of graphite, wherewith absorption of the pulse of laser radiation takes place in the skin-layer of graphite and the graphite is heated in the region of the skin-layer to the temperature of graphite-to-diamond phase transition. After cooling the produced layer of diamond, the steps of heating successive layers of the sample of graphite with pulses of laser radiation and cooling said layers are repeated until complete transformation of the graphite to diamond.

Abstract: The process is an arc jet CVD diamond deposition process with very low methane, less than 0.07%, and the addition of water. The resulting material has is characterized by a narrow Raman peak, a relatively large lattice constant, and a charge carrier collection distance of at least 25 microns.Also disclosed is a particle detector device which makes use of the diamond material according to the invention.

Abstract: The present invention improves the adhesive property by pretreating under uniform conditions the substrate surface of metal, ceramics or glass etc. with a poor adhesive property, by accelerating ions under an electric field to the substrate in advance of a diamond-like film forming process. In light of the fact that a diamond-like film forming process by ionized deposition uses thermal electron ionization means and an electric potential is applied to a grid to accelerate ionized hydrocarbon ions, the present invention could attain the aimed purpose by ionizing and then accelerating a bombardment gas such as argon as a pretreatment process in the same apparatus.

Abstract: A method of making n-type semiconducting diamond is disclosed, which is doped with boron-10 at the time of diamond formation and bombarded with neutrons for in-situ conversion of boron-10 to lithium-7, while filtering the neutrons from high energy components during irradiation.

Abstract: A modified process for synthesizing diamond having developed by further improving a process of diamond synthesis based on combustion method, which provides diamond grains 1.5 mm or larger in crystal diameter at good economy. The process comprises burying one or two or more seed crystal diamond grain(s) 2 into the surface of a substrate 1, and striking a combustion flame on said seed crystal diamond grain(s) 2 while cooling the substrate 1 to thereby allow diamond to grow on the seed crystal diamond 2 into a larger diamond grain.

Abstract: Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate. Articles formed by the disclosed processes are described, including three-dimensional objects.

Abstract: A method and apparatus for generating plasmas adapted for chemical vapor deposition, etching and other operations, and in particular to the deposition of large-area diamond films, wherein a chamber defined by sidewalls surrounding a longitudinal axis is encircled by an axially-extending array of current-carrying conductors that are substantially transverse to the longitudinal axis of the chamber, and a gaseous material is provided in the chamber. A high-frequency current is produced in the conductors to magnetically induce ionization of the gaseous material in the chamber and form a plasma sheath that surrounds and extends along the longitudinal axis and conforms to the sidewalls of the chamber. A work surface extending in the direction of the longitudinal axis of the chamber is positioned adjacent a sidewall, exposed to the plasma sheath and treated by the plasma.

Abstract: Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate. Articles formed by the disclosed processes are described, including three-dimensional objects.

Abstract: The deposition of high quality diamond films at high linear growth rates and substrate temperatures for microwave-plasma chemical vapor deposition is disclosed. The linear growth rate achieved for this process is generally greater than 50 .mu.m/hr for high quality films, as compared to rates of less than 5 .mu.m/hr generally reported for MPCVD processes.

Abstract: A method for synthesizing diamond by chemical vapor deposition (CVD) is described. The method produces diamond of high purity and high crystallizability having various uses at low cost and at high speed. In a first method, a mixture of oxygen gas and a carbon-containing compound gas, and optionally an inert gas, is introduced into a reaction vessel. In a second method, a mixture containing at least one of fluorine gas, chlorine gas, a nitrogen oxide gas, sulfur dioxide, an aforementioned mixture of oxygen gas and a carbon-containing compound gas, or a mixture thereof with an inert gas is introduced into the reaction vessel. A plasma is generated by use of an electromagnetic field, thereby producing diamond on a base material placed in the vessel.

Abstract: A method and system for manufacturing diamond film. The method involves forming a fullerene vapor, providing a noble gas stream and combining the gas with the fullerene vapor, passing the combined fullerene vapor and noble gas carrier stream into a chamber, forming a plasma in the chamber causing fragmentation of the fullerene and deposition of a diamond film on a substrate.

Abstract: In accordance with the present invention, a field emission device is made by pre-activating ultra-fine diamond particles before applying them to the device substrate. This initial pre-activation increases manufacturing speed and reduces cost and reduces potential damage to the device substrate from exposure to high temperature hydrogen plasma.

Abstract: A method of growing diamond crystals in excess of 10 .mu.m in diameter from industrial diamond "seeds" having mean diameters of approximately 1.5 .mu.m is disclosed. The diamonds are grown by exposing the seed diamonds to C.sub.70 in the presence of reducing agents such as phosphorus or selenium in evacuated cells at moderate temperatures and pressures.

Abstract: A method of doping diamond with relatively large atoms such as aluminium, phosphorus, arsenic and antimony is provided. The method involves implanting the dopant atoms at a low temperature to create a damaged region of point defects in the form of vacancies and interstitial dopant atoms within the crystal lattice of the diamond, and annealing the diamond to reduce the lattice damage and cause dopant interstitial atoms to diffuse into lattice positions. The implantation dose will be low and such as to create density of implanted dopant atoms of no greater than 2.5.times.10.sup.18 cm.sup.3.

Abstract: Human-made diamond, as well as naturally found diamond, is a transparent, superhard, crystalline, and electrically nonconductive form of carbon. In this invention, an electrical current of supercritical density alone produces the transformation of graphite to diamond. The entire graphite-to-diamond transformation requires only a few millionths of a second. Using the principles of the invention, diamond can be produced in a variety of shapes, such as loose debris, rods, fibers, bars, dust, etc. In addition to diamond, Buckminster Fuller Balls, known also as C-60 carbon fullerines, are produced using the process and apparatus of the invention.

Abstract: A diamond crystal forming method with which a diamond crystal is formed on a substrate by a sputtering process uses high-frequency energy in the frequency range of 40 MHz to 250 MHz to form plasma.

Abstract: A continuous thin diamond film having a thickness of less than about 2 microns has a low leakage. The thin diamond film may be supported on a supporting grid and may be incorporated into an X-ray window. The film may be formed in a DC assisted CVD process where in a first phase a relatively high concentration of a carbonaceous gas is introduced into the reactor and in a second phase the concentration of the carbonaceous gas is reduced to a lower value.

Abstract: The present invention provides a method for coating a titanium based component with diamond-like carbon to reduce the thrombogeneticity of the component. In a preferred embodiment, the titanium based component is a heart valve.According to the present invention, the component is placed in a vacuum chamber and heated to about 600.degree. -650.degree. C. (1112.degree.-1202.degree. F.). Thereafter, silicon is then deposited onto the component, and the component is simultaneously bombarded with a beam of energetic ions to form a metal-silicide bonding layer. The component then is cooled to at least about 100.degree. C. (212.degree. F.), preferably about 80.degree. C. (176.degree. F.), and a diamond-like carbon precursor is condensed onto the metal-silicide bonding layer. The precursor is simultaneously bombarded with a beam of energetic ions to form a coating of diamond-like carbon.

Abstract: An ultrasmooth diamond film has a thickness greater than about ten microns and an average grain size less than about 0.5 micron. The ultrasmooth diamond film of the present invention is grown using ordinary microwave plasma CVD methods, with a metal vapor source included in the reactor to produce vapor during the growth of the film. The metal vapor source may be chosen from the first row transition elements, chromium, iron, cobalt, and nickel, or from the lanthanides praseodymium, europeum, or erbium. Any metal capable of existing in the vapor phase in the presence of the hydrogen plasma, will cause formation of the ultrasmooth film of the present invention.

Abstract: The present invention relates to an improved method of depositing a diamond-like carbon film onto a substrate by low temperature plasma-enhanced chemical vapor deposition (PECVD) from a hydrocarbon/helium plasma. More specifically, the diamond-like carbon films of the present invention are deposited onto the substrate by employing acetylene which is heavily diluted with helium as the plasma gas. The films formed using the process of the present invention are characterized as being amorphous and having dielectric strengths comparable to those normally observed for diamond films. More importantly, however is that the films produced herein are thermally stable, optically transparent, absorbent in the ultraviolet range and hard thus making them extremely desirable for a wide variety of applications.

Abstract: A process for gas phase synthesis of diamond using a DC plasma jet where a plasma jet generated by DC arc discharge using a DC plasma torch is made to strike a substrate and grow diamond on the substrate, wherein use is made of a plurality of plasma torch anodes, these are arranged coaxially in a telescoped structure, a magnetic field is applied to these in accordance with need to cause the arc to rotate or the electrode is rotated so as to perform gas phase synthesis of diamond.

Abstract: A synthetic single crystal diamond for wire drawing die; the process of manufacturing it and a wire drawing die to utilize it are disclosed. At least one plane of the diamond for wire drawing die is a cleavage plane of (111) faces, and the drawing hole of wire drawing die lies vertical to the cleavage plane. The diamond for the wire drawing die is produced by providing a synthetic single crystal having 20-400 ppm nitrogen of Ib type diamond. A groove is made on the diamond surface parallel to (111) faces employing energy beams such as a laser beam, an ion beam and an electron beam. A wedge is struck into the groove to cleave the diamond, and a plate is obtained. Furthermore, the plate is divided into polyhedrons, employing either an energy beam or a blade. The cleavage plane of the polyhedron is almost parallel to the (111) faces of crystal, therefore the cleavage plane is used as the standard plane to build the drawing hole.

Abstract: A process of preparing diamond, e.g., diamond fiber, by subjecting a hydrocarbon material, e.g., a hydrocarbon fiber, to a plasma treatment in a gaseous feedstream for a sufficient period of time to form diamond, e.g., a diamond fiber is disclosed. The method generally further involves pretreating the hydrocarbon material prior to treatment with the plasma by heating within an oxygen-containing atmosphere at temperatures sufficient to increase crosslinking within said hydrocarbon material, but at temperatures insufficient to melt or decompose said hydrocarbon material, followed by heating at temperatures sufficient to promote outgassing of said crosslinked hydrocarbon material, but at temperatures insufficient to convert said hydrocarbon material to carbon.

Abstract: There is provided a system for the manufacture of a diamond film. A plasma generator generates a hydrogen atom containing plasma stream into which a hydrocarbon containing gas is fed. The plasma dissociates the hydrocarbon to carbon radicals and carbon which are deposited on a substrate where the carbon crystallizes to a diamond film. The efficiency of the system is increased by heating the hydrogen source gas prior to generation of the plasma. Other means to increase the effectiveness of the system include using a plurality of plasma streams and shaping the plasma stream, A low internal strain, high quality optical film is generated by depositing the carbon on a substrate supported by a heat sink having nonuniform thermal conductivity such that the thermal gradient across the surface of the heat sink is less than about 8.degree. C./centimeter.

Abstract: The present invention relates to a diamond vibration plate for a speaker having high sound velocity or E/.rho. and which is superior in high-pitched tone performance. Conventional diamond vibration plates which are made overall from crystalline diamond were apt to split or break at a flange due to the high rigidity. According to the present invention periphery of the flange is circularly cut by laser beams to eliminate rugged circumference. The laser treatment also converts the crystalline diamond of the flange into non-diamond carbon. The resulting vibration plate with a central spherical part of crystalline diamond and a periphery of a flange of non-diamond carbon excels both in high frequency property and mechanical strength.

Abstract: Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate.

Abstract: A process forms an amorphous carbon film over a solid, which film has physical and chemical properties similar to those of diamond. Its ancillary objects are the solid bodies so coated and the self-sustained film obtained in a subsequent stage of dissolution of said substrate. The process includes generating a highly accelerated beam of carbon-hydrogenated ions, which beam is made to impact with sufficiently high energy on the surface of the substrate. The beam is concentrated by electrostatic lenses and homogenized by a magnetic mass separator. The process forms on a solid substrate, a film with properties similar to those of diamond, such as high hardness, high chemical stability, transparency, high heat conductivity and high electric resistivity; obtainable at ambient temperature, and which is simpler than known procedures.

Abstract: Broadly, the present invention is directed to polycrystalline diamond of improved thermal conductivity. The novel polycrystalline diamond consists essentially of at least 99.5 wt-% isotopically-pure carbon-12 or carbon-13. The inventive polycrystalline diamond is formed from at least 99.5 wt-% isotopically-pure carbon-12 or carbon-13. Single-crystal isotopically-pure carbon-12 and carbon-13 diamond are known to possess improved thermal conductivity. Polycrystalline diamond, however, possesses lower thermal conductivity patterns deleteriously impacted by, for example, impurities, isotopic effects, and grain boundary scattering. In fact, grain boundary scattering would lead the skilled artisan to believe that the thermal conductivity of polycrystalline diamond would be substantially unaffected by the isotopic nature of the diamond itself.

Abstract: A process for producing diamond includes a step of bringing a columnar cathode and a tubular pilot anode provided concentrically around the cathode, into proximity to a plasma jetting port of a front end portion of a tubular main anode provided concentrically around the pilot anode. According to the process, a voltage is applied across the cathode and the pilot anode to convert a pilot gas to the form of a plasma. Then, the cathode is moved away from the pilot anode along a common axis. The process also includes the step of holding the discharge voltage between the cathode and the pilot anode at a first preselected voltage, and then applying voltage across the cathode and the main anode to convert a main gas to the form of a plasma. Subsequently, at least the pilot anode is moved away from the main anode along the common axis while maintaining the discharge voltage between the cathode and the pilot anode at the first preselected voltage.

Abstract: A carbon cluster film has a precisely controlled stable electrical conductivity which does not deteriorate in a short period of time in air. Such a carbon cluster film having a stable electrical conductivity is formed by introducing an impurity into a thin film of fullerenes by ion implantation. The fullerenes include C.sub.60, C.sub.70 or the like.

Abstract: A powder of diamond or high-pressure phase boron nitride core particles charged into a coating space as it is dispersed, and a precursor of a coat forming substance allowed to contact and/or impinge against the particles in the powder of core particles so that their surfaces are covered with the coat forming substance, thereby preparing coated diamond or high-pressure phase boron nitride particles which are subsequently sintered. The thusly produced diamond of high-pressure phase boron nitride sinter is composed of coated core particles of high performance that are superhard, uniform, dense and sintered firmly, and which have a controlled microstructure.

Abstract: A method for forming synthetic diamond coatings on surfaces, such as select surfaces of boat hulls, motor vehicle underbodies, chemical storage tanks and the like, which are subject to corrosion and/or erosion. In a preferred form, the apparatus is portable and is either hand-holdable or is carried by a self propelled vehicle or computer controlled automatic manipulator. In a particular form, the apparatus includes a chamber having an opening therein with a circumscribing rim adapted to be forced against a portion of the surface to be coated while one or more carbon atom, containing materials in gaseous and/or solid particle form are fed to the surface interior of such rin and form a synthetic diamond coating or the like thereagainst.

Abstract: A method of manufacturing a radiation sensor element. The method includes providing a diamond body which comprises crystalline diamond material which has a nitrogen impurity concentration of less than 150 ppm. The body is typically a synthetic diamond manufactured by a high temperature/high pressure process, or by a chemical vapour deposition process. The body is hydrogenated to cause atomic hydrogen to be incorporated into the diamond crystal lattice. Hydrogenation can be carried out by ion implantation, or by exposing the body to a hydrogen plasma. Where the sensor element is to be used as a counting diamond, electrical contacts are formed on the body, for example by ion implantation.

Abstract: A method for bonding CVD diamond to silicon. The first step of the method involves subsequently depositing a transition lawyer 48 on a diamond layer 46 of a composite wafer 40. Once the transition layer 48 has been deposited, wafer layer 50 comprised of silicon, is bonded or deposited to the transition layer 48. In this method, the transition layer 48 comprises carbon and silicon, with the portion of the transition layer 48 adjacent the diamond layer 46 being comprised of substantially carbon and the portion of the transition layer 48 adjacent the wafer layer 50 being comprised of substantially silicon. With the method, sharp interfaces and poor thermal matches between the layers in the composite wafer can be minimized. As a result, the layers in the composite wafer are less likely to delaminate and the composite wafer is likely to warp or bow due to mismatched film stresses.

Abstract: A method of making a diamond film on a graphite substrate is disclosed, which comprises the steps of forming a layer of carbon-containing compound on a surface of the graphite substrate and controlling said compound to be rich or lean in carbon with respect to the stoichiometric carbon content in the compound to adjust the adherence of a diamond layer to be deposited on said layer of carbon-containing compound; and depositing a synthetic diamond layer on said layer of carbon-containing compound.

Abstract: A rapid process for the preparation of diamond articles in which a porous, dense preform of diamond particles created by particle packing methods is subjected to forced flow chemical vapor infiltration of a carbon containing reagent gas resulting in the preparation of thick diamond articles.

Abstract: A continuous diamond structure deposited by chemical vapor deposition is disclosed having at least two thermal conductivity diamond layers controlled by the diamond growth rate where one thermal conductivity diamond layer is grown at a high growth rate of at least one micron per hour for hot filament chemical vapor deposition and at least 2-3 microns per hour for microwave plasma assisted chemical vapor deposition, on a substrate such as molybdenum in a chemical vapor deposition chamber and at a substrate temperature that promotes the high growth rate, and the other thermal conductivity diamond layer is grown at a growth rate and substrate temperature lower than the high growth rate diamond layer. High growth rate and low growth rate diamond layers can be deposited in any sequence to obtain a continuous diamond structure that does not show distinguishable, separate, crystalline columnar layers, having improved thermal conductivity.

Abstract: Chemical vapor deposition method for producing a fine grained smooth growth surfaced diamond film on a substrate employs a hydrogen/hydrocarbon gaseous atmosphere containing an amount of nitrogen effective to inhibit the growth of the diamond grains deposited on the substrate.

Abstract: The purity and toughness of a batch of diamond grains is increased by separating a portion containing undesirable inclusions form a remaining higher purity portion and annealing the higher purity portion in a reducing atmosphere for a sufficient period of time to enhance the toughness of the higher purity portion.

Abstract: A process for depositing diamond on a substrate using a microwave plasma generator including introducing a feed which includes diamond forming constituents in a desired ratio to the microwave plasma generator, and providing sufficient microwave power to the microwave plasma generator to produce a greenish-colored plasma which emits a spectrum monitored to maintain a relative emission intensity ratio of two of the constituents in a predetermined range, for depositing high quality diamond at an extremely high rate on the substrate placed proximate or in the plasma.

Abstract: The steady state operating parameters of a low pressure cyclic hot-filament chemical vapor deposition process for making diamond, i.e., nucleation-growth and graphite removal, are applied as controlled sequential steps to favor nucleation and growth.

Abstract: Diamond materials are formed by sandwiching a carbon-containing material in a gap between two electrodes. A high-amperage electric current is applied between the two electrode plates so as cause rapid-heating of the carbon-containing material. The current is sufficient to cause heating of the carbon-containing material at a rate of at least approximately 5,000.degree. C./sec, and need only be applied for a fraction of a second to elevate the temperature of the carbon-containing material at least approximately 1000.degree. C. Upon terminating the current, the carbon-containing material is subjected to rapid-quenching (cooling). This may take the form of placing one or more of the electrodes in contact with a heat sink, such as a large steel table. The carbon-containing material may be rapidly-heated and rapidly-quenched (RHRQ) repeatedly (e.g., in cycles), until a diamond material is fabricated from the carbon-containing material.