SYSTEMS AND METHODS FOR SINGLE MAGNETRON SPUTTERING

• US 20170022604A1
• Filed: 07/24/2015
• Published: 01/26/2017
• Est. Priority Date: 07/24/2015
• Status: Active Grant

• Current Assignee: AES Global Holdings Pte Ltd. (Advanced Energy Industries, Inc. (China))
• Original Assignee: Advanced Energy Industries Incorporated
• Inventors: Christie, David, Larson, Skip B.
• Granted Patent: US 10,373,811 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C23C 14/3485 using pulsed power to the target
• CPC Class Codes: C23C 14/3492 Variation of parameters during sputtering
• CPC Class Codes: H01J 37/3405 Magnetron sputtering
• CPC Class Codes: H01J 37/3438 Electrodes other than cathode
• CPC Class Codes: H01J 37/3476 Testing and control
• CPC Class Codes: H01J 37/3488 Constructional details of particle beam apparatus not otherwise provided for, e.g. arrangement, mounting, housing, environment; special provisions for cleaning or maintenance of the apparatus

Abstract

A system and method for single magnetron sputtering are described. One example includes a system having a power supply, a plasma chamber enclosing a substrate, an anode, and a target for depositing a thin film material on the substrate. This example also has a datastore with uncoated anode characterization data and an anode sputtering adjustment system including an anode analysis component to generate a first health value. The first health value is indicative of whether the anode is coated with a dielectric material. This example also has an anode power controller to receive the first health value and provide an anode-energy-control signal to the pulse controller of the pulsed DC power supply to adjust a second anode sputtering energy relative to a first anode sputtering energy to eject at least a portion of the dielectric material from the anode.

Claims

1. A system for single magnetron sputtering comprising:

a plasma chamber enclosing a substrate, an anode, and a target for depositing a thin film material on the substrate;

a pulsed DC power supply coupled to the target and the anode, the pulsed power supply including a pulse controller to supply both a first target sputtering energy to the target with a first voltage polarity and a second target sputtering energy to the target with the first voltage polarity, the pulse controller configured to supply a first anode sputtering energy immediately following the first target sputtering energy with a second voltage polarity, and supply a second anode sputtering energy immediately following the second target sputtering energy with the second voltage polarity, wherein the second voltage polarity is opposite the first voltage polarity;

an anode monitor system comprising a voltage monitor to detect a first anode voltage at a first process variable value;

a datastore comprising uncoated anode characterization data derived from characteristics of an uncoated anode that is not coated with a dielectric material, the uncoated anode characterization data including a first expected anode voltage stored in association with the first process variable value; and

an anode sputtering adjustment system coupled to the datastore and the anode monitor system, the anode sputtering adjustment system including;

an anode analysis component to generate, based upon a difference between the first anode voltage and the first expected anode voltage, a first health value, the first health value indicative of whether the anode is coated with the dielectric material; and

an anode power controller to receive the first health value and provide an anode-energy-control signal to the pulse controller of the pulsed DC power supply to adjust the second anode sputtering energy relative to the first anode sputtering energy to eject at least a portion of the dielectric material from the anode.

2. The system of claim 1, wherein the anode analysis component includes:

a processor coupled to the voltage monitor; and

a non-transitory tangible processor-readable medium comprising instructions that, when executed by the processor, cause the processor to;

access, using the process variable value, the datastore to obtain the expected voltage value;

calculate a difference between the first anode voltage and the first expected anode voltage; and

generate the first health value based upon the difference between the first anode voltage and the first expected anode voltage.

3. The system of claim 1, wherein the anode analysis component includes:

a field programmable gate array coupled to the voltage monitor; and

a non-transitory tangible medium comprising instructions that, when used to configure the filed programmable gate array, cause the filed programmable gate array to;

access, using the process variable value, the datastore to obtain the expected voltage value;

calculate a difference between the first anode voltage and the first expected anode voltage; and

generate the first health value based upon the difference between the first anode voltage and the first expected anode voltage.

4. The system of claim 1, wherein the voltage monitor comprises:

a first voltage sensor operatively coupled to the anode; and

a second voltage sensor operatively coupled to the target;

wherein

the voltage monitor obtains a voltage differential between the anode and the target.

5. The system of claim 1, wherein the uncoated anode characterization data comprises:

a plurality of data sets, each data set including a particular expected voltage value and a particular process variable value.

6. The system of claim 1, wherein the anode monitor system further comprises:

a current sensor to detect a first current value across the anode, the current sensor providing the first current value as the first process variable value.

7. The system of claim 1, wherein the anode monitor system further comprises:

a mass flow meter to detect a first oxygen flow rate value into the plasma chamber, the mass flow meter providing the first oxygen flow rate value as the first process variable value.

8. The system of claim 2, wherein:

the anode monitor system is configured to detect a second anode voltage at a period of time from the detecting the first anode voltage, and at a second process variable value, the second process variable value having the same value as the first process variable value;

the instructions include instructions that cause the processor to;

compare the second voltage to the second expected voltage for a second health value; and

compare the second health value and the first health value relative to the period of time.

9. A method for single magnetron sputtering comprising:

enclosing a substrate, an anode, and a target for depositing a thin film material on the substrate in a plasma chamber;

alternately applying target sputtering energy to the target and anode sputtering energy to the anode;

monitoring an anode voltage at a process variable value;

accessing a datastore, the datastore having uncoated anode characterization data derived from characteristics of an uncoated anode that is not coated with a dielectric material, the uncoated anode characterization data including a first expected anode voltage defined by the uncoated anode characterization data of the uncoated anode anode at a first process variable value;

obtaining, using the first process variable value, the first expected voltage value from the datastore;

generating a first health value based upon the difference between the monitored anode voltage and the first expected anode voltage; and

adjusting the anode sputtering energy based upon the first health value to eject material from the anode.

10. The method of claim 9, further comprising:

detecting, after a period of time, a second anode voltage at the first process variable value;

generating a second health value based upon the difference between the second anode voltage and the first expected anode voltage; and

comparing the second health value and the first health value relative to the period of time to determine a rate at which the anode is becoming coated.

11. The method of claim 9, wherein adjusting the anode sputtering energy based upon the first health value includes adjusting at least one of the anode sputtering voltage and a time the anode sputtering energy is applied to the anode.

12. The method of claim 9, wherein adjusting the anode sputtering energy includes adjusting an anode sputtering voltage to greater than about 30 Volts.

13. The method of claim 9, further comprising:

deriving the uncoated anode characterization data from the anode while the anode is uncoated; and

populating the datastore with the uncoated anode characterization data.

14. The method of claim 13, further comprising:

replacing the anode with a replacement anode;

deriving the uncoated anode characterization data from the replacement anode while the replacement anode is uncoated; and

populating the datastore with the uncoated anode characterization data derived from the replacement anode

15. A power supply system for a single magnetron sputtering system, the power supply system comprising:

a target lead to couple to a target and an anode lead to couple to an anode;

a pulse controller to alternately apply target sputtering energy to the target lead and anode sputtering energy to the anode lead;

an anode monitor system to monitor a voltage of the anode lead;

a datastore configured to store uncoated anode characterization data including a first expected anode voltage stored in association with a first process variable value; and

an anode energy adjustment system having an output to instruct the pulse controller to adjust the anode sputtering energy when the monitored anode voltage at the first process variable value is greater than a threshold deviation from the first expected anode voltage.

16. The power supply system of claim 15, wherein the anode energy adjustment system comprises:

a processor;

a non-transitory tangible processor-readable medium encoded with processor readable instructions to perform a method for maintaining a health of the anode, the method comprising;

accessing, using the first process variable value, the datastore to obtain the first expected voltage value;

generating a first health value based upon the difference between the monitored anode voltage and the first expected anode voltage; and

adjusting the anode sputtering energy based upon the first health value to eject material from the anode.

17. The power supply system of claim 16, wherein:

the anode monitor system is configured to detect a first voltage of the anode lead and a second voltage of the anode lead at a period of time from the detecting the first voltage, and at a second process variable, the second process variable having the same value as the first process variable; and

the non-transitory tangible processor-readable medium comprises instructions that, when executed by the processor, cause the processor to;

compare the second voltage to a second expected voltage to generate a second anode health value, and

compare the second anode health value to the first anode health value relative to the period of time.