Abstract:
A diamond foam article comprises diamond deposited material on a substrate having an open contiguous structure at least partially filled with a filler material. Methods for forming a diamond foam article comprise providing a foam substrate; preparing the foam substrate for diamond deposition; depositing diamond material on the foam substrate by one of several diamond deposition methods; and at least partially filling the diamond foam article with a filler material. Diamond foam articles are bonded to other components.
Abstract:
Porous and non-porous compositions include diamond particles, non-diamond particles, or mixtures of particles consolidated with polycrystalline diamond. The composite compositions of the present invention may be formed by a process which includes the steps of preforming the particles into a preform having a desired shape, and consolidating the preform with polycrystalline diamond. The polycrystalline diamond is preferably formed using CVD techniques including application of sufficient microwave energy to maintain the preform at a temperature of between about 670.degree. and 850.degree. C. The preform may be rotated during a portion of the deposition process.
Abstract:
A block of dielectric material having a long axis and a short axis and having low losses at a selected microwave frequency and a dielectric constant selected to produce a desired degree of phase modulation is mounted on a rotatable shaft in an orientation perpendicular to the long and short axes and arranged inside a waveguide feeding a CVD reactor containing a plasma species. The block is spun by a rotational force applied to the shaft at an angular acceleration such that the two axes of the block successively intersect the axis of the waveguide within the decay period of the plasma species. The frequency of phase modulation can be varied by changing the angular acceleration of the shaft, and the amplitude of the phase modulation can be varied by changing the ratio of block length to thickness and/or by selecting a material with higher dielectric constant. The incident microwave power may be modulated as a function of angular position of the spin shaft. By moving the apparent plasma and modulating the applied microwave power, a customized temperature profile may be achieved over a desired substrate area.
Abstract:
A CVD diamond material, substantially free of voids, has an average crystallite size greater than about 15 microns, a maximum intensity of the diamond Raman peak in counts/sec divided by the intensity of photoluminescence at 1270 cm.sup.-1 greater than about 3, a Raman sp.sup.3 full width half maximum less than about 6 cm.sup.-1 and a diamond-to-graphite Raman ratio greater than about 25. The diamond material may also comprise carbon atoms with a C.sup.13 content less than 0.05 atomic %.
Abstract:
The present invention comprises an article formed from a plurality of diamond particles and non-diamond particles compatible with diamond deposition preformed into a desired shape. Each of the particles has first surface regions in contact with immediately adjacent other ones of the particles, and second surface regions spaced apart from the immediately adjacent other ones of said particles to define boundaries of inter-particle voids between the immediately adjacent ones of the particles. The voids are infiltrated with high thermal conductivity CVD diamond material continuously coating the second surface regions of the particles and comprising merged growth fronts from the second surface regions of individual immediately adjacent ones of the particles into the inter-particle voids. The high thermal conductivity CVD diamond material has an average crystallite size greater than about 15 microns, an intensity ratio of diamond- Raman-peak-to-photoluminescence background intensity greater than about 20, a maximum intensity of the diamond Raman peak in counts/sec divided by the intensity of photoluminescence at 1270 cm.sup.-1 greater than about 3, a Raman sp.sup.3 full width half maximum less than about 6 cm.sup.-1 and a diamond-to-graphite Raman ratio greater than about 25. The thermal conductivity of the CVD diamond materials is in excess of 17 Wcm.sup.-1 K.sup.-1.
Abstract:
Processes are provided for consolidating diamond particles into a mechanically stable diamond mass, called a diamond ceramic. A compacted aggregation of diamond particles is subjected to low pressure PECVD conditions in the presence of atomic hydrogen, with or without a carbon source gas, whereby a mechanically stable diamond ceramic is formed substantially devoid of interstitial spaces.
Abstract:
An article comprises a heat source, a heat sink, and a high-efficiency diamond material interposed between and thermally coupled to the heat source and the heat sink. The heat source and the high-efficiency diamond material have a contact area greater than 1 square centimeter.
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:
A method for growing a diamond film, substantially free of voids, having an average crystallite size greater than about 15 microns, a maximum intensity of the diamond Raman peak in counts/sec divided by the intensity of photoluminescence at 1270 cm.sup.-1 greater than about 3, a Raman sp.sup.3 full width half maximum less than about 6 cm.sup.-1, and a diamond-to-graphite Raman ratio greater than about 25, includes the steps of preparing a substrate by abrasion with diamond particles; placing the substrate in a CVD reactor; depositing diamond during a first deposition stage by providing an atmosphere consisting essentially of a mixture of about 200 sccm H.sub.2 and 10 sccm CH.sub.4, at a pressure of about 90 Torr, providing between about 1,800 and 1,950 watts of microwave power at a frequency of about 2.45 GHz to ignite and sustain a plasma in the region of said substrate, and maintaining the substrate at a temperature of between about 625.degree. C. and 675.degree. C. for a period of time sufficient to form a diamond layer which is substantially continuous; depositing a diamond during a second deposition stage by providing an atmosphere consisting essentially of a mixture of about 200 sccm H.sub.2, 4.6 sccm CO, and 9 ccm of CH.sub.4 at a pressure of about 90 Torr, providing between about 1,800 and 1,950 watts of microwave power at a frequency of between about 2.45 GHz and maintaining said substrate material at a temperature of between about 625.degree. C. and 675.degree. C. for a period of time sufficient to form a diamond layer having a desired thickness; and removing the substrate material from said CVD reactor.
Abstract:
A carrier for a laser diode bar comprises a generally rectangularly shaped block formed from a dielectric material having a high thermal conductivity. The block includes a stepped recess formed therein having a height essentially equal to one half the height of a laser diode bar to be mounted thereon. An assembly for mounting a laser diode bar comprises a pair of carriers in contact with one another and oriented such that their stepped recesses are in facing relationship to one another. A laser diode bar is positioned between the carriers in the space left by their combined stepped recesses. A plurality of assemblies may be placed in contact with or separated from one another.