Method for balancing consumption of targets in pulsed dual magnetron sputtering (DMS) processes
A sputtering system and method are disclosed. The system has at least one dual magnetron pair having a first magnetron and a second magnetron, each magnetron configured to support target material. The system also has a DMS component having a DC power source in connection with switching components and voltage sensors. The DMS component is configured to independently control an application of power to each of the magnetrons, and to provide measurements of voltages at each of the magnetrons. The system also has one or more actuators configured to control the voltages at each of the magnetrons using the measurements provided by the DMS component. The DMS component and the one or more actuators are configured to balance the consumption of the target material by controlling the power and the voltage applied to each of the magnetrons, in response to the measurements of voltages at each of the magnetrons.
1. A method for sputtering comprising:
arranging at least two magnetrons to form at least one dual magnetron pair;
generating DC power with a DC power supply;
converting the DC power to pulsed-DC power with switching components;
applying the pulsed-DC power to each of the at least two magnetrons, wherein each pulse of the pulsed-DC power includes a voltage boost portion and a quasi-DC burning voltage interval;
affixing target material to each of the at least two magnetrons;
sputtering the target material on to a substrate;
independently controlling an application of power to each of the magnetrons;
measuring voltages of the quasi-DC burning voltage interval at each of the magnetrons with voltage measurement components;
controlling the voltages during the quasi-DC burning voltage interval at each of the magnetrons with one or more actuators using the measurements of voltages; and
balancing consumption of the target material by independently controlling the power that is applied to each of the at least two magnetrons and independently controlling the voltage applied to each of the magnetrons in response to the measurements of voltages at each of the magnetrons.
2. The method of claim 1 , wherein controlling the voltage that is applied to each magnetron includes one or more of:
modifying the flow of reactive gas to one magnetron relative to the other magnetron; and
adjusting a rotation speed of each of the magnetrons.
3. The method of claim 1 , comprising:
predicting a mismatch in target consumption.
4. The method of claim 3 , wherein predicting a mismatch comprises calculating a quasi-DC burning voltage of each of the first magnetron and the second magnetron.
5. The method of claim 4 , comprising:
calculating a sputtering yield of the target surface of the first target; and
calculating a sputtering yield of the target surface of the second target.
6. A method for sputtering comprising:
converting DC power to pulsed-DC power with switching components;
applying the pulsed-DC power to each of at least two magnetrons wherein each pulse of the pulsed-DC power includes a voltage boost portion and a quasi-DC burning voltage interval;
controlling the switching components to balance an application of power to each of the at least two magnetrons;
obtaining measurements of the quasi-DC burning voltage interval at each of the magnetrons; and
independently controlling the application of the voltages during the quasi-DC burning voltage interval to the magnetrons with actuators based upon the measurements of the quasi-DC burning voltage.
7. The method of claim 6 , wherein controlling the application of the voltages includes:
modifying the flow of reactive gas to one magnetron relative to the other magnetron.
8. The method of claim 6 , wherein controlling the application of the voltages includes:
adjusting a rotation speed of each of the magnetrons.