Variable-temperature vapor deposition process
A method of growing a single crystal diamond material synthesized using a homoepitaxial chemical vapor deposition process. The method includes the steps of placing a free-standing diamond starting seed substrate on a substrate holder within a reaction chamber for chemical vapor deposition; feeding a process gas into the reaction chamber, the process gas including hydrogen gas; igniting a plasma within the reaction chamber to activate the process gas by adjusting the substrate temperature to increase to a first target substrate temperature; adding a carbon-containing gas to the process gas once the substrate temperature is at or near the first target substrate temperature to initiate diamond growth; and adjusting the substrate temperature to a second target substrate temperature that is different from the first target substrate temperature during the diamond growth.
1 . A method of growing a single crystal diamond material synthesized using a homoepitaxial chemical vapor deposition process, the method comprising:
placing a free-standing diamond starting seed substrate on a substrate holder within a reaction chamber for chemical vapor deposition;
feeding a process gas into the reaction chamber, the process gas including hydrogen gas;
igniting a plasma within the reaction chamber to activate the process gas by adjusting the substrate temperature to increase to a first target substrate temperature;
adding a carbon-containing gas to the process gas once the substrate temperature is at or near the first target substrate temperature to initiate diamond growth; and
adjusting the substrate temperature to a second target substrate temperature that is different from the first target substrate temperature during the diamond growth;
wherein the diamond growth at or near the first target substrate temperature defines a first stage of the diamond growth and the diamond growth at or near the second target substrate temperature defines a second stage of the diamond growth, and wherein the first stage of diamond growth includes bi-dimensional nucleation growth morphologies, and the second stage of diamond growth includes step-flow growth morphologies.
2 . The method of claim 1 , wherein the first target substrate temperature is configured to inhibit hillock and inclusion formation to promote high crystallinity.
3 . The method of claim 1 , further comprising the steps of adjusting the substrate temperature to one or more additional different substrate target temperatures.
4 . The method of claim 1 , wherein the second target substrate temperature is at least 10° C. higher or lower than the first target substrate temperature.
5 . The method of claim 1 , wherein the second target substrate temperature is at least 20° C. higher or lower than the first target substrate temperature.
6 . The method of claim 1 , further comprising adjusting the carbon or non-carbon containing gas concentrations in the process gas during the growth of the diamond.
7 . The method of claim 1 , wherein the process gas further includes a gas selected from the group consisting of nitrogen-carrier gas, boron-carrier gas, phosphorus-carrier gas, n-type dopant carrier gas, p-type dopant carrier gas, and a combination thereof.
8 . The method of claim 1 , wherein the adjusting of the substrate temperature is controlled by adjusting plasma power.
9 . The method of claim 1 , wherein the adjusting of the substrate temperature is controlled by adjusting a resistive substrate holder heater power.
10 . The method of claim 1 , wherein the adjusting of the substrate temperature is controlled by adjusting a cooling water supply.
11 . A method of growing a single crystal diamond material synthesized using a homoepitaxial chemical vapor deposition process, the method comprising:
placing a free-standing diamond starting seed substrate on a substrate holder within a reaction chamber for chemical vapor deposition;
feeding a process gas into the reaction chamber, the process gas including hydrogen gas;
igniting a plasma within the reaction chamber to activate the process gas by adjusting the substrate temperature to increase to be within a first substrate temperature range;
adding a carbon-containing gas to the process gas once the substrate temperature is within the first substrate temperature range to initiate diamond growth; and
adjusting the substrate temperature to a second substrate temperature range that is outside the first substrate temperature range during the diamond growth;
wherein the diamond growth at or near the first target substrate temperature range defines a first stage of the diamond growth and the diamond growth at or near the second target substrate temperature range defines a second stage of the diamond growth, and wherein the first stage of diamond growth includes bi-dimensional nucleation growth morphologies, and the second stage of diamond growth includes step-flow growth morphologies.
12 . The method of claim 11 , wherein the first substrate temperature range is configured to inhibit hillock and inclusion formation to promote crystallinity.
13 . The method of claim 11 , further comprising the steps of adjusting the substrate temperature to one or more different substrate temperature ranges.
14 . The method of claim 13 , wherein the first substrate temperature range, the second substrate temperature range, or the one or more different substrate temperature ranges define a range of ±12° C.
15 . The method of claim 13 , wherein the first substrate temperature range, the second substrate temperature range, or the one or more different substrate temperature ranges define a range of ±10° C.
16 . The method of claim 13 , wherein the first substrate temperature range, the second substrate temperature range, or the one or more different substrate temperature ranges define a range of ±5° C.
17 . The method of claim 13 , wherein the first substrate temperature range, the second substrate temperature range, or the one or more different substrate temperature ranges define a range of ±2° C.
18 . The method of claim 11 , further comprising adjusting carbon or non-carbon containing gas concentrations in the process gas during the growth of the diamond.
19 . The method of claim 11 , wherein the process gas further includes a gas selected from the group consisting of nitrogen-carrier gas, boron-carrier gas, phosphorus-carrier gas, n-type dopant carrier gas, p-type dopant carrier gas, and a combination thereof.
20 . The method of claim 11 , wherein the adjusting of the substrate temperature is controlled by adjusting plasma power.
21 . The method of claim 11 , wherein the adjusting of the substrate temperature is controlled by adjusting a resistive heater.
22 . The method of claim 11 , wherein the adjusting of the substrate temperature is controlled by adjusting a cooling water supply.
23 . A method of growing a single crystal diamond material synthesized using a homoepitaxial chemical vapor deposition process, the method comprising:
placing a diamond substrate on a substrate holder within a chemical vapor deposition reaction chamber;
feeding a process gas into the reaction chamber, the process gas including hydrogen gas;
igniting a plasma within the reaction chamber to activate the process gas by adjusting a substrate temperature to be within a first substrate temperature range defining a bi-dimensional nucleation growth regime;
feeding a carbon-containing gas to the process gas to grow diamond on the diamond substrate within a bi-dimensional nucleation growth regime; and
adjusting the substrate temperature to a second substrate temperature range that is outside the first substrate temperature range during the diamond growth, wherein the second substrate temperature range defines a step-flow growth regime.
24 . The method of claim 23 , wherein the first stage of diamond growth is configured to inhibit hillock and inclusion formation to promote high crystallinity.
25 . The method of claim 23 , further comprising adjusting carbon or non-carbon containing gas concentrations in the process gas during the growth of the diamond.
26 . The method of claim 23 , wherein the process gas further includes a gas selected from the group consisting of nitrogen-carrier gas, boron-carrier gas, phosphorus-carrier gas, n-type dopant carrier gas, p-type dopant carrier gas, and a combination thereof.
27 . The method of claim 23 , wherein the adjusting of the substrate temperature is controlled by adjusting plasma power.
28 . The method of claim 23 , wherein the adjusting of the substrate temperature is controlled by adjusting a resistive heater.
29 . The method of claim 23 , wherein the adjusting of the substrate temperature is controlled by adjusting a cooling water supply.