System and method for producing synthetic diamond

Abstract

Synthetic monocrystalline diamond compositions having one or more monocrystalline diamond layers formed by chemical vapor deposition, the layers including one or more layers having an increased concentration of one or more impurities (such as boron and/or isotopes of carbon), as compared to other layers or comparable layers without such impurities. Such compositions provide an improved combination of properties, including color, strength, velocity of sound, electrical conductivity, and control of defects. A related method for preparing such a composition is also described., as well as a system for use in performing such a method, and articles incorporating such a composition.

1 . A method of forming a synthetic monocrystalline diamond comprising the steps of: 
 a) forming on a substrate by a chemical vapor deposition process a first synthetic diamond layer incorporating one or more impurities and one or more carbon isotopes; and    b) selecting concentrations of the one or more carbon isotopes and the one or more impurities during the formation of the first synthetic diamond layer, in order to form the first synthetic diamond layer with a predetermined lattice constant having a corresponding level of lattice strain.    
   
   
       2 . The method of  claim 1 , wherein the step of forming the first synthetic diamond layer comprises expanding atomic spacing of the first synthetic diamond layer by incorporating the one or more impurities and contracting atomic spacing of the first synthetic diamond layer by incorporating the one or more carbon isotopes.  
   
   
       3 . The method of  claim 2 , wherein the expanding effect of incorporating the one or more impurities introduces lattice strain to the formed first synthetic diamond layer.  
   
   
       4 . The method of  claim 2 , wherein the step of selecting the concentrations of the one or more carbon isotopes and the one or more impurities comprises counteracting the expanding effect of incorporating the one or more impurities with the contracting effect of incorporating the one or more carbon isotopes in forming the first synthetic diamond layer such that the lattice strain introduced to the first synthetic diamond layer during its formation is either tailored to a specific level or substantially eliminated.  
   
   
       5 . The method of  claim 1 , wherein the level of lattice strain corresponds to how much the lattice constant of the first synthetic diamond layer varies from a lattice constant of natural diamond.  
   
   
       6 . The method of  claim 1 , wherein formation of dislocations in the first synthetic diamond layer can be lessened or eliminated by further forming by a chemical vapor deposition process a series of synthetic diamond layers that alternate in tension and compression thereon.  
   
   
       7 . The method of  claim 6 , wherein the series of alternating synthetic diamond layers would redirect the dislocations into the plane of the alternating synthetic diamond layers such that one or more second synthetic diamond layers could be grown by a chemical vapor deposition process onto the first synthetic diamond layer and have substantially no strain.  
   
   
       8 . The method of  claim 1 , further comprising the step of initially determining the lattice constant of the first synthetic diamond layer to be formed.  
   
   
       9 . The method of  claim 1 , wherein the monocrystalline synthetic diamond is formed having a controlled level of lattice match or mismatch between the substrate and the first synthetic diamond.  
   
   
       10 . The method of  claim 9 , wherein the controlled level of lattice match comprises each of the first synthetic diamond layer and the substrate having substantially aligned lattice constants.  
   
   
       11 . The method of  claim 10 , wherein each of the first synthetic diamond layer and the substrate have substantially no lattice strain.  
   
   
       12 . The method of  claim 9 , wherein the controlled level of lattice mismatch comprises the first synthetic diamond layer having a lattice constant that is not aligned with a lattice constant of the substrate.  
   
   
       13 . The method of  claim 12 , wherein the first synthetic diamond layer has a level of lattice strain and the substrate has substantially no lattice strain.  
   
   
       14 . The method of  claim 12 , wherein the first synthetic diamond layer has substantially no lattice strain and the substrate has a level of lattice strain.  
   
   
       15 . The method of  claim 12 , wherein the first synthetic diamond layer and the substrate each have a level of lattice strain, but the formation of the first synthetic diamond layer to the substrate results in effectively but not literally aligning the lattice constants of the diamond layer and the substrate.  
   
   
       16 . The method of  claim 15 , wherein the first synthetic diamond layer is under tension and the substrate is under compression.  
   
   
       17 . The method of  claim 1 , wherein the incorporation of one or more impurities comprises adding the one or more impurities during the diamond formation process.  
   
   
       18 . The method of  claim 1 , wherein the incorporation of one or more impurities comprises adding the one or more impurities after the diamond formation process.  
   
   
       19 . The method of  claim 1 , wherein the substrate comprises a layer of pure diamond having about 99% 12C isotope and about 1% 13C isotope.  
   
   
       20 . The method of  claim 1 , wherein the substrate comprises a layer of diamond formed by a high pressure, high temperature process.  
   
   
       21 - 51 . (canceled)