Nanosecond pulser ADC system
A nanosecond pulser system is disclosed. In some embodiments, the nanosecond pulser system may include a nanosecond pulser having a nanosecond pulser input; a plurality of switches coupled with the nanosecond pulser input; one or more transformers coupled with the plurality of switches; and an output coupled with the one or more transformers and providing a high voltage waveform with a amplitude greater than 2 kV and a frequency greater than 1 kHz based on the nanosecond pulser input. The nanosecond pulser system may also include a control module coupled with the nanosecond pulser input; and an control system coupled with the nanosecond pulser at a point between the transformer and the output, the control system providing waveform data regarding an high voltage waveform produced at the point between the transformer and the output.
1. A nanosecond pulser system comprising:
a nanosecond pulser comprising:
a pulser input;
a high voltage DC power supply;
one or more solid-state switches coupled with the high voltage DC power supply and the pulser input, the one or more solid-state switches switching the high voltage DC power supply based on input pulses provided by the pulser input; and
a pulser output coupled with the one or more transformers that outputs a high voltage waveform with an amplitude greater than about 2 kV and a pulse repetition frequency greater than about 1 kHz based on the pulser input; and
a control system coupled with the nanosecond pulser at a measurement point and coupled with the pulser input, the control system providing the input pulses to the pulser input, the control system measures the voltage at the measurement point, and the control system adjusts the voltage, pulse repetition frequency, or duty cycle of the input pulses based on the measured voltage.
2. The nanosecond pulser system according to claim 1 , wherein the measurement point comprises a point between the transformer and the pulser output.
3. The nanosecond pulser system according to claim 1 , wherein:
the nanosecond pulser system further comprises an electrode coupled with the pulser output; and
the measurement point is at the electrode.
4. The nanosecond pulser system according to claim 1 , further comprising one or more transformers coupled with the one or more switches.
5. The nanosecond pulser system according to claim 1 , wherein the control system measures the pulse repetition frequency at the measurement point, and adjusts the pulse repetition frequency of the input pulses based on the measured pulsed repetition frequency.
6. The nanosecond pulser system according to claim 1 ,
wherein the input pulses include a first burst comprising a first plurality of low voltage pulses, each of the first plurality of low voltage pulses having a first pulse width;
wherein the input pulses include a second burst comprising a second plurality of low voltage pulses each of the second plurality of low voltage pulses having a second pulse width; and
wherein the second pulse width is greater than the first pulse width.
7. The nanosecond pulser system according to claim 1 , wherein the control system:
receives input data specifying a voltage and a pulse repetition frequency corresponding to an desired high voltage waveform;
compares an output pulser waveform measured at the measurement point with the desired high voltage waveform; and
determines adjustments to the pulser input to produce the desired high voltage waveform.
8. The nanosecond pulser system according to claim 1 , wherein the control system comprises a voltage divider that reduces the high voltage waveform by a factor of 1000.
9. The nanosecond pulser system according to claim 1 , wherein the control system includes an analog to digital converter that converts the measured high voltage waveform into a digital signal.
10. The nanosecond pulser system according to claim 1 , further comprising metal shielding disposed between the nanosecond pulser and the control system.
11. The nanosecond pulser system according to claim 1 , wherein the nanosecond pulser comprises a resistive output stage, and wherein the measurement point is across a resistor in the resistive output stage.
12. A nanosecond pulser system comprising:
a nanosecond pulser having a pulser output that outputs a high voltage waveform that includes a plurality of bursts where each burst comprises a plurality of pulses with an amplitude greater than 2 kV and a pulse repetition frequency greater than 1 kHz; and
a control system that controls a number of characteristics of the high voltage waveform including the number of pulses in each burst, a pulse repetition frequency, a pulse width, and a pulse voltage.
13. The nanosecond pulser system according to claim 12 , wherein the control system controls at least one characteristics of the high voltage waveform with a resolution of less than about 1 μs.
14. The nanosecond pulser system according to claim 12 , wherein the control system controls at the period between pulses with an accuracy less than about 10 μs.
15. The nanosecond pulser system according to claim 12 , wherein the control system controls the number of characteristics of the high voltage waveform in response to a plasma processing recipe.
16. The nanosecond pulser system according to claim 15 , wherein the plasma processing recipe comprises a plurality of stages and each stage is associated with an ion current, a chamber pressure, and a gas mixture.
17. The nanosecond pulser system according to claim 12 , wherein the control system controls the number of characteristics of the high voltage waveform in real-time.
18. The nanosecond pulser system according to claim 12 ,
wherein the high voltage waveform includes a first burst comprising a first plurality of pulses, each of the first plurality of pulses having a first pulse width;
wherein the high voltage waveform includes a second burst comprising a second plurality of pulses each of the second plurality of pulses having a second pulse width; and
wherein the second pulse width is greater than the first pulse width.
19. The nanosecond pulser system according to claim 12 ,
wherein the nanosecond pulser comprises a transformer and the output that outputs the high voltage waveform; and
wherein the control system is coupled with the nanosecond pulser at a point between the transformer and the pulser output.
20. A nanosecond pulser system comprising:
a nanosecond pulser having a pulser output that outputs pulses with an amplitude greater than 2 kV and a pulse repetition frequency greater than 1 kHz;
an electrode in a plasma chamber;
a measurement point located at or near the electrode;
a sensor coupled with the measurement point that provides an electronic sensor signal representing voltage waveforms occurring at the measurement point; and
a control system coupled with the sensor and the nanosecond pulser, the control system controls the pulser output in response to the electronic sensor signal.
21. The nanosecond pulser system according to claim 20 ,
wherein the voltage waveforms include a first burst comprising a first plurality of pulses, each of the first plurality of pulses having a first pulse width;
wherein the voltage waveforms include a second burst comprising a second plurality of pulses each of the second plurality of pulses having a second pulse width; and
wherein the second pulse width is greater than the first pulse width.
22. The nanosecond pulser system according to claim 20 , wherein the control system controls the pulser output in response to a plasma processing recipe.
23. The nanosecond pulser system according to claim 22 , wherein the plasma processing recipe comprises a plurality of stages and each stage is associated with an ion current, a chamber pressure, and a gas mixture.