Method of growing a single crystal diamond
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 growing a diamond, the method comprising:
placing a single crystal diamond seed on a holder in a CVD chamber;
creating a plasma cloud in the CVD chamber;
growing single crystal diamond on the seed from hydrocarbon gas in the presence of atomic hydrogen; and
maintaining nitrogen content in the CVD chamber low enough to result in a diamond crystal that has less than 20 ppm nitrogen.
2 . The method of claim 1 wherein the grown diamond is at least 20 micrometers thick.
3 . The method of claim 1 and further comprising removing the seed from the grown diamond.
4 . The method of claim 1 wherein the seed is selected from the group consisting of natural diamond crystal or synthetic CVD diamond crystal.
5 . The method of claim 1 wherein the CVD chamber is rich in hydrogen.
6 . The method of claim 6 wherein the hydrogen concentration is at least approximately 99%.
7 . The method of claim 6 wherein the hydrocarbon gas comprises approximately 1% methane.
8 . The method of claim 1 wherein the grown diamond has a thermal conductivity greater than approximately 2200 W/mK.
9 . The method of claim 1 wherein the grown diamond has a 13 C content of at least approximately 0.1%.
10 . The method of claim 1 wherein the grown diamond has a 13 C content of at least approximately 0.5%.
11 . The method of claim 1 wherein the grown diamond has a 13 C content of at least approximately 0.8%.
12 . The method of claim 1 wherein the plasma cloud is created from an activation technique selected from the group consisting of hot filament, D.C., R.F., microwave, arc jet, and combustion.
13 . A method of growing a diamond, the method comprising:
selecting a single crystal diamond seed;
creating a plasma cloud in a CVD chamber;
growing single crystal diamond on the seed from methane and hydrogen in the CVD chamber;
maintaining nitrogen content in the CVD chamber low enough to result in a diamond crystal that has less than 20 ppm nitrogen; and
removing the seed from the grown diamond.
14 . The method of claim 13 wherein the grown diamond is at least 20 approximately micrometers thick.
15 . The method of claim 13 wherein the seed is removed by grinding or sawing.
16 . The method of claim 13 and further comprising forming a sacrificial layer on the seed prior to growing the diamond.
17 . The method of claim 16 wherein the seed is removed by removing the sacrificial layer.
18 . The method of claim 13 wherein the hydrogen concentration is approximately 99%.
19 . The method of claim 13 wherein the methane gas comprises approximately 1% methane.
20 . The method of claim 13 wherein the grown diamond has a thermal conductivity greater than approximately 2200 W/mK.
21 . The method of claim 13 wherein the diamond is grown at a rate in excess of approximately 10 micrometers per hour.
22 . The method of claim 13 wherein the grown diamond has a 13 C content of at least approximately 0.1%.
23 . The method of claim 13 wherein the grown diamond has a 13 C content of at least approximately 0.5%.
24 . The method of claim 13 wherein the grown diamond has a 13 C content of at least approximately 0.8%.
25 . The method of claim 13 and further comprising ensuring the formation of atomic hydrogen proximate the growing single crystal diamond.
26 . The method of claim 13 wherein the plasma cloud is created from an activation technique selected from the group consisting of hot filament, D.C., R.F., microwave, arc jet, and combustion.
27 . A method of growing a diamond, the method comprising:
growing single crystal diamond on a single crystal seed from methane and hydrogen in a CVD chamber; and
maintaining nitrogen content in the CVD chamber low enough to result in a diamond crystal that has less than 10 ppm nitrogen at a rate of at least approximately 10 micrometers per hour.
28 . The method of claim 27 and further comprising creating a plasma cloud proximate the single crystal seed.
29 . The method of claim 27 wherein the plasma cloud is created from an activation technique selected from the group consisting of hot filament, D.C., R.F., microwave, arc jet, and combustion.
30 . The method of claim 28 and further comprising ensuring the presence of atomic hydrogen proximate the single crystal seed.
31 . The method of claim 27 and further comprising removing the seed from the grown diamond.
32 . The method of claim 27 wherein the grown diamond has a 13 C content of at least approximately 0.1%.
33 . The method of claim 27 wherein the grown diamond has a 13 C content of at least approximately 0.5%.
34 . The method of claim 27 wherein the grown diamond has a 13 C content of at least approximately 0.8%.
35 . The method of claim 27 wherein the methane and hydrogen comprises approximately 1% methane.
36 . A method of growing a diamond, the method comprising:
selecting a single crystal diamond seed;
growing single crystal diamond on the seed from approximately 1% methane and approximately 99% hydrogen in a CVD chamber at a rate of at least approximately 10 micrometers per hour;
maintaining nitrogen content in the CVD chamber low enough to result in a diamond crystal that has less than 10 ppm nitrogen incorporated into substitutional sites or interstitial sites; and
removing the seed from the grown diamond.
37 . The method of claim 36 and further comprising creating a plasma cloud proximate the single crystal seed.
38 . The method of claim 37 wherein the plasma cloud is created from an activation technique selected from the group consisting of hot filament, D.C., R.F., microwave, arc jet, and combustion.
39 . The method of claim 36 and further comprising ensuring the presence of atomic hydrogen proximate the single crystal seed.
40 . The method of claim 36 wherein the grown diamond has a 13 C content of at least approximately 0.1%.
41 . The method of claim 36 wherein the grown diamond has a 13 C content of at least approximately 0.5%.
42 . The method of claim 36 wherein the grown diamond has a 13 C content of at least approximately 0.8%.