Provided is a synthetic single crystal diamond containing conjugants each composed of one vacancy and one boron atom, wherein the concentration of boron atoms based on atom numbers is 0.1 ppm or more and 100 ppm or less.

The present invention relates to a method for manufacturing a diamond substrate, and more particularly, to a method of growing diamond after forming a structure of an air gap having a crystal correlation with a lower substrate by heat treatment of a photoresist pattern and an air gap forming film material on a substrate such as sapphire (Al.sub.2O.sub.3). Through such a method, a process is simplified and the cost is lowered when large-area/large-diameter single crystal diamond is heterogeneously grown, stress due to differences in a lattice constant and a coefficient of thermal expansion between the heterogeneous substrate and diamond is relieved, and an occurrence of defects or cracks is reduced even when a temperature drops, such that a high-quality single crystal diamond substrate may be manufactured and the diamond substrate may be easily self-separated from the heterogeneous substrate.

Diamond bodies and methods of manufacture are disclosed. Diamond bodies are formed from at least a bimodal, alternatively a tri-modal or higher modal, feedstock having at least one fraction of modified diamond particles with a fine particle size (0.5-3.0 μm) and at least one fraction of diamond particles with coarse particle size (15.0 to 30 μm). During high pressure-high temperature processing, fine particle sized, modified diamond particles in the first fraction preferentially fracture to smaller sizes while preserving the morphology of coarse particle sized diamond particles in the second fraction. Diamond bodies incorporating the two fractions have a microstructure including second fraction diamond particles dispersed in a continuous matrix of first fraction modified diamond particles and exhibit improved wear characteristics, particularly for wear associated with drilling of geological formations.

A solid state combinatorial synthesis of particulate diamond ranging in size from the macroscopic down to the nanoscale, which entails: a) forming a solution having a source of reactant atoms, a tetrahedranoidal compound reactant, and a solvent vehicle; b) forming liquid droplets of the solution; c) evaporating the solvent vehicle from the liquid droplets of the solution to form particles containing a homogenous solid mixture of the reactants; and d) exposing the particles of the homogeneous solid mixture to a high energy discharge thereby forming diamond particles.

A solid state combinatorial synthesis of particulate diamond ranging in size from the macroscopic down to the nanoscale, which entails: a) forming a solution having a source of reactant atoms, a tetrahedranoidal compound reactant, and a solvent vehicle; b) forming liquid droplets of the solution; c) evaporating the solvent vehicle from the liquid droplets of the solution to form particles containing a homogenous solid mixture of the reactants; and d) exposing the particles of the homogeneous solid mixture to a high energy discharge thereby forming diamond particles.

Provided is a method for producing a polycrystalline diamond body, the method including a first step of heat-treating a powder of high-pressure-phase carbon at higher than or equal to 1300° C. to obtain a heat-treated carbon powder, and a second step of sintering the heat-treated carbon powder under conditions of greater than or equal to 12 GPa and less than or equal to 25 GPa and higher than or equal to 1200° C. and lower than or equal to 2300° C. to obtain a polycrystalline diamond body.

Provided is a method for producing a polycrystalline diamond body, the method including a first step of heat-treating a powder of high-pressure-phase carbon at higher than or equal to 1300° C. to obtain a heat-treated carbon powder, and a second step of sintering the heat-treated carbon powder under conditions of greater than or equal to 12 GPa and less than or equal to 25 GPa and higher than or equal to 1200° C. and lower than or equal to 2300° C. to obtain a polycrystalline diamond body.

A method for forming mesophase pitch can include applying a stimulus to a first amount of coal tar to form a first amount of mesophase pitch. The stimulus can include one or more of an electromagnetic field (“EMF”) or a magnetic field. The method can further include evaluating a characteristic of the first amount of mesophase pitch, changing a parameter of the stimulus in response to evaluating the characteristic of the first amount of mesophase pitch, and applying the stimulus exhibiting the changed parameters to a second amount of coal tar to form mesophase pitch.

A method for forming mesophase pitch can include applying a stimulus to a first amount of coal tar to form a first amount of mesophase pitch. The stimulus can include one or more of an electromagnetic field (“EMF”) or a magnetic field. The method can further include evaluating a characteristic of the first amount of mesophase pitch, changing a parameter of the stimulus in response to evaluating the characteristic of the first amount of mesophase pitch, and applying the stimulus exhibiting the changed parameters to a second amount of coal tar to form mesophase pitch.

The present disclosure relates to a system and method for synthesis of condensed nano-materials to at least one of create nanoparticles or modify existing nanoparticles. In one embodiment the system may have a source of liquid precursor, with the liquid precursor including a compound therein. A flow control element and a compression wave generating subsystem are also included. The flow control element is in communication with the source of the liquid precursor and creates a jet of liquid precursor. The compression wave generating subsystem drives a compression wave through at least a substantial portion of a thickness of the jet of liquid precursor to sufficiently compress the jet of liquid precursor, and to increase pressure and temperature of the jet of liquid precursor, to at least one of create nanoparticles or modify existing nanoparticles.