System level power delivery to plasma processing load

0001(Citation of related application) This application claims the interests of US Provisional Patent Application No. 61 / 429,472 (filed January 4, 2011). The details of the application No. 61 / 429,472 are hereby incorporated by reference in their entirety for any suitable purpose.

0002(Field of invention) The present invention relates to maintaining consistent power delivery to plasma processing loads. More specifically, it relates to system-level integration of generators, matched networks, and sensors, and their monitoring and control.

0003In semiconductor manufacturing, continuous efforts to miniaturize features pose significant challenges for tool manufacturers, process developers, and the like. Requirements such as higher uniformity, tighter control of critical dimensions, reduced plasma damage, thinner layers, and shorter process times, combined with the introduction of new materials, are more sophisticated in the development of semiconductor processing tools. Demand that. These requirements apply to plasma chambers and also extend to power delivery systems.

0004Human operators typically monitor multiple sensor outputs from generators and matched networks, adjust a number of parameters in incomplete and relatively slow attempts, and are consistent with plasma loads. Maintain power delivery. The operator may interact with an external controller that collects information from the various components of the system, displays this information for the operator, and transmits commands from the operator to the various components of the system. This configuration worked in the past, but it is becoming increasingly clear that it may not be suitable for current systems.

0005As an example, major advances in the etching process have been brought about by the introduction of state-of-the-art RF power supplies with advanced capabilities, including generator frequency tuning between pulse transmission and multiple generator synchronous pulse transmission. However, even in this state-of-the-art power delivery system, the system components are still suppressed because they act independently and are therefore controlled independently. In particular, generators provide a tunable frequency for pulsed power, but matched networks are difficult to detect, measure, and respond to pulsed signals, thus leveraging the capabilities of the generator. It is difficult to do. Operators tend to select the optimal variable capacitor position in the matched network and then start the process (ie, a suboptimal solution to minimize real-time power reflections). Therefore, significant improvements were made to the plasma processing power supply, but these continue to be suppressed by the independent control of the generator and the matching network.

0006FIG. 1 illustrates generators, matched networks, and plasma loads well known to those of skill in the art. The generator 102 provides power to the plasma load 106 via the matching network 104, in which case the matching network 104 substantially increases the impedance experienced by the generator 102 as the impedance of the load 106 changes. In addition, the internal impedance can be changed so that it remains constant (eg, 50Ω). The matched network 104 typically measures the power incident on the matched network 104 and the power reflected from the matched network 104 to the generator 102, and then uses these values to determine the impedance of the plasma load 106. Includes sensor 116 to calculate. The generator 102 often includes a sensor 114 that measures the power output of the generator 102. Sensors 114, 116 sometimes communicate their measurements to the user via the external user interface 130. The user then commands the matching network 104 and / or the generator 102 to adapt in an attempt to tune the system.

0007In particular, the generator 102 can be instructed to produce a particular electrical characteristic (eg, power or frequency), or the desired power delivered to the plasma load 106 can be selected. , The generator 102 can be tuned to achieve that power. Similarly, the matching network 104 can be instructed to operate at a particular impedance, or to be tuned to achieve the desired reflected power. In some cases, both the generator 102 and the matched network 104 can be instructed to tune to meet the desired power output characteristics.

0008The generator 102 sometimes includes a communication and logic board 112 that facilitates communication between the sensor 114, the radio frequency (RF) engine 113, and the user interface 130. The RF engine 113 can generate RF power and control the amplitude and waveform of the power generated by the generator 102. Similarly, the matching network 104 sometimes includes a communication and logic board 122 that facilitates communication between the sensor 116, the impedance control system 115, and the user interface 130. The impedance control system 115 can control the impedance of the matching network 104, for example, by having the motor drive board adjust the variable capacitor of the matching network 104.

0009The power delivery system 100 can slowly adapt to changes in the dynamic power profile (power accuracy or consistency) from the plasma load 106 and the generator 102. For example, there is a delay between the moment of measurement by either sensor 114 or 116 and the moment when the measured value reaches the user interface 130. There is also a delay when the instruction is replied to the generator 102 and the matched network 104.

0010In terms of accuracy, sensor 116 of the matched network 104 samples only after a threshold current or voltage has been detected, and therefore does not sample while the power is being compared to the threshold. Smaller sample sizes and inability to sample from the start of pulse transmission lead to less accurate impedance measurements. Also, despite calibrating each sensor 114, 116, the sensors 114, 116 still have some level of error and therefore, when used in combination, as a net effect, the individual sensors 114, It has an error almost equivalent to the sum of the errors of 116. Finally, impedance measurements are most accurate when the frequency of the power being measured is known. Sensor 116 of the matched network 106 needs to measure the frequency of power reaching the matched network 104, which is typically calculated based on the measured value of sensor 116 as it has some error. The impedances made also typically have a corresponding degree of error. As is clear, speed and accuracy are limited in conventional systems similar to those in Figure 1.

0011Quality can also be hampered in the art because the inaccuracy and slow speed of the power delivery system 100 can lead to inconsistent power delivery. In some cases, multiple generators power a single plasma load over multiple matched networks. Power quality is of particular concern in these cases, as each generator and matching network must consider not only the plasma load, but also other generators that are mutually visible. In other words, the challenge of impedance matching increases when multiple generators are involved, and therefore power quality is further degraded when multiple generators are used.

0012The system in Figure 1 could have been appropriate in the past, but is accurate to quickly adapt to the nonlinear dynamic plasma load characteristics of new processes with more stringent requirements for accuracy, stability, and short processing steps. It may not be appropriate to provide consistent power.

<p num="0013"> The present disclosure monitors the characteristics of the generator, matching network, and plasma load through one or more sensors, and these via a local controller to improve power delivery accuracy and consistency for the plasma load. Discusses power delivery systems and methods of operation that are configured to control the components of the.</p><p num="0014"> One aspect of the disclosure can be characterized as a power delivery system. The power delivery system can include a generator, a matched network, a first sensor, and a local controller. The generator can be configured to provide power to the plasma load. The matching network can be configured to impedance match the output of the generator to the plasma load. The first sensor is configured to measure the voltage, current, phase, impedance, and / or power of the power at the output of the generator and the corresponding measured voltage, current, phase, impedance, and / or power. Can be configured to generate. The local controller receives the measured voltage, current, phase, impedance, and / or power from the sensor, receives the user power delivery requirements, and the measured voltage, current, phase, impedance, and / or power and the user. It can be configured to analyze power delivery requirements and instruct generators and / or matched networks to adjust one or more operating parameters to meet user power delivery requirements.</p><p num="0015"> Another aspect of the disclosure can be characterized as a method involving monitoring, analyzing, and relaying motion. In particular, the method can include monitoring the electrical characteristics of the power output of the generator and providing the electrical characteristics of the power output to the local controller. The method can also include analyzing the electrical properties of the power output. The method can further include relaying instructions to the generator and matched network based on the analysis, thereby allowing simultaneous tuning of the generator and matched network.</p><p num="0016"> Yet another aspect of the disclosure can be characterized as a power control system for a power delivery system. The power control system can include a first sensor and a local controller. The first sensor can be configured to monitor the power output of the generator and the impedance experienced by the generator. The generator can be configured to provide power to the plasma load via a matched network. The local controller can be configured to communicate with the first sensor and manage the tuning of the generator and the matching network. Tuning is responsible for the power output of the generator and the impedance experienced by the generator. For example, the present invention provides the following items. (Item 1) It s a power delivery system, With a generator that is configured to provide power to the plasma load, A matching network configured to impedance match the output of the generator to the plasma load. It is configured to measure the voltage, current, phase, impedance, and / or power of the power at the output of the generator and generate the corresponding measured voltage, current, phase, impedance, and / or power. The first sensor, which is configured, With a local controller With The local controller Receiving the measured voltage, current, phase, impedance, and / or power from the sensor, Receiving user power delivery requirements and Analyzing the measured voltage, current, phase, impedance, and / or power and the user power delivery requirements. To instruct the generator and / or the matched network to adjust one or more operating parameters to meet the user power delivery requirements. A system that is configured to do. (Item 2) The system of item 1, wherein the one or more operating parameters include generator frequency or matched network impedance. (Item 3) The system of item 1, wherein the sensor is configured to measure the power output of the generator and the impedance experienced by the generator. (Item 4) The system according to item 1, wherein the local controller is located in the generator. (Item 5) The system according to item 1, wherein the local controller is located in the consistent network. (Item 6) It further comprises a second sensor that communicates with the local controller, which is the voltage, current, phase, impedance, and / or power, non-electricity of the plasma chamber between the matched network and the plasma load. The system according to item 1, which is configured to measure the characteristics or the non-electrical characteristics of the plasma load. (Item 7) The system of item 1, wherein the local controller identifies the generator, the matching network, and the first sensor. (Item 8) The system of item 1, wherein the local controller is configured to be a single conduit for user interaction with the components of the power delivery system. (Item 9) To monitor the electrical characteristics of the power output of the generator and provide the electrical characteristics of the power output to the local controller. Analyzing the electrical characteristics of the power output Based on the analysis, the instructions are relayed to the generator and the matching network, thereby allowing simultaneous tuning of the generator and the matching network. Including methods. (Item 10) Receiving the generator identification in the local controller and Receiving the identification of the matched network on the local controller and To identify the generator and the matching network and to analyze the electrical characteristics of the power output. Based on the analysis of the operating parameters and the electrical characteristics, the instructions can be relayed to the generator and the matching network to allow simultaneous tuning of the generator and the matching network. The method according to item 9, further comprising. (Item 11) The method of item 10, wherein the simultaneous tuning comprises tuning the frequency of the generator and the impedance of the matching network. (Item 12) The method of item 10, wherein the identification of the generator and the matching network comprises a brand, model, or serial number. (Item 13) The method of item 10, wherein the identification of the generator and the matched network includes operating characteristics. (Item 14) It is a power control system of a power delivery system. A first sensor configured to monitor the power output of the generator and the impedance experienced by the generator so that the generator provides power to the plasma load via a matched network. The first sensor, which is configured, With a local controller that communicates with the first sensor With A power control system in which the local controller is configured to manage the tuning of the generator and the matching network, the tuning causing the power output of the generator and the impedance experienced by the generator. (Item 15) The power control system according to item 14, wherein the local controller is software or firmware configured to operate on the generator or the processor and memory of the matched network. (Item 16) The power control system according to item 14, wherein the local controller is a processor that operates software or firmware and is configured for addition to an existing power delivery system. (Item 17) The power control system according to item 14, wherein the local controller is configured to identify the first sensor, the generator, and the matched network. (Item 18) The power control system of item 17, wherein the tuning takes into account the identification of the first sensor, the identification of the generator, and the identification of the matching network. (Item 19) 14. The power control system of item 14, further comprising a second sensor configured to characterize the power output of the matched network delivered to the plasma load. (Item 20) 18. The power control system of item 18, wherein the second sensor is configured to monitor the characteristics of the plasma chamber, the plasma being maintained by the power delivered from the power delivery system. (Item 21) The power control system according to item 14, wherein the local controller is configured to manage simultaneous tuning of the frequency of the generator and the impedance of the matching network. (Item 22) 14. The power control system of item 14, wherein the local controller interfaces with the first sensor, the generator, and user inputs to and from the matching network. (Item 23) 22. The power control system of item 22, wherein the local controller is configured to communicate with an external controller, and the user interfaces with the power delivery system via the external controller. (Item 24) The local controller Receiving user power delivery requirements and Generating instructions for the generator and the matching network to meet the user power delivery requirements. Passing the instruction to the generator and the matching network The power control system according to item 22, which is configured to do so.</p>

0017A clear and easier understanding of the various purposes and advantages of the present invention and a more complete understanding will be made in connection with the accompanying drawings by referring to the following forms for carrying out the invention and the accompanying claims. Will be recognized.<figref num="1">FIG. 1 illustrates generators, matched networks, and plasma loads well known to those of skill in the art.</figref><figref num="2A">FIG. 2a-2c illustrates an embodiment of a power delivery system that includes a generator that provides power to a matched network.</figref><figref num="2B">FIG. 2a-2c illustrates an embodiment of a power delivery system that includes a generator that provides power to a matched network.</figref><figref num="2C">FIG. 2a-2c illustrates an embodiment of a power delivery system that includes a generator that provides power to a matched network.</figref><figref num="3">FIG. 3 illustrates an embodiment of a multiple generator power delivery system.</figref><figref num="4">FIG. 4 illustrates another embodiment of a multiple generator power delivery system.</figref><figref num="5">FIG. 5 illustrates yet another embodiment of a multiple generator power delivery system.</figref><figref num="6">FIG. 6 illustrates a method of supplying power to a plasma load according to an embodiment of the present disclosure.</figref><figref num="7">FIG. 7 illustrates an embodiment of a machine according to one embodiment of the present disclosure.</figref>

0018The present disclosure is confronted in the prior art by recognizing that even conventional and state-of-the-art systems are still limited by their autonomous design, in particular generators and matched networks operate independently. Overcome the challenges to be done. The present disclosure describes systems, methods, and devices for integrating communication, measurement, and control between components of a power delivery system (also known as a power generation and delivery system). Some of the advantages of this approach are accurate generation over a wide dynamic range, faster power stabilization during transitions, and reduced reflected power for both pulsed and continuous wave (CW) power. The ability to provide is mentioned.

0019FIG. 2a-2c illustrates three embodiments of the power delivery system 200. The power delivery system 200 provides power to the plasma load 206, in which case the matching network 204 minimizes reflected power. The power output of the generator 202 is provided to the matching network 204 via the first transmission medium 208 and then to the plasma load 206 via the second transmission medium 210. The first sensor 214 and the optional second sensor 218 monitor the electrical characteristics of power by measuring one or more of voltage, current, phase, impedance, and power, and this information is passed on to the local controller. Pass (or relay) to. The local controller 212 resides either within the generator 202 or the matching network 204 (see Figure 2b) or anywhere in the power delivery system 200 (see Figure 2c), and the generator 202, the matching network 204, and Manages communication between one or more of sensors 214, 218. The local controller 212 can also manage communication between the user and any component of the power delivery system 200. The local controller 212 is rapidly adjustable and can manage the power delivery system 200 so that constant and accurate power is delivered to the plasma load 206 according to one or more power delivery requirements. ..

0020One or more sensors 214, 218 monitor the power to the local controller 212. In particular, the first sensor 214 can monitor the power output of the generator 202 as well as the impedance experienced by the generator 202. The local controller 212 analyzes the measurements provided by the first sensor 214 (optionally and also the second sensor 218) in light of the power delivery requirements. This can determine the operating parameters for the generator 202 and the matched network 204 that are determined to be sufficient to meet the power delivery requirements, and the generator 202 and the matched network 204 meet the power delivery requirements. Therefore, it is possible to instruct (or relay the instruction) to adjust the internal parameters of those components.

0021The use of this integrated power delivery system 200, i.e., the local controller 212 and the first sensor 212 (optionally, the second sensor 218) disclosed herein, has several advantages over prior art. Has. First, the ability to tune the matching network 204 and the generator 202, or pulse out or modify the output waveform of the generator 202, at the same time by integrating the control and operation of the various components of the power delivery system 200. At the same time, new power delivery methods such as the ability to tune the matched network 204 become possible. Second, the system and approach enable fast adjustable, accurate and consistent power delivery for the plasma load 206. The speed of the power delivery system 200 is particularly useful in dynamic power applications (eg, the output of the pulsed generator 202).

0022The ability to adjust power delivery more quickly may be due, in part, to avoiding the delay experienced by conventional systems where the sensor must first measure frequency before measuring impedance. The local controller 214 provides the first sensor 214 with generator operating parameters such as frequency so that the first sensor 214 does not need to measure the frequency before starting impedance sampling. Early sampling means that the impedance can be determined faster than that in the art. The local controller 214 also provides the first sensor 214 with an indicator of the start of pulse transmission or power waveform changes, and therefore the first sensor 214 needs to detect such changes before starting sampling. Sex can be prevented. This also allows the first sensor 214 to start measuring impedance earlier than sensors in the art.

0023The power delivery system 200 also improves the accuracy of power delivery in four ways. First, when using multiple sensors to measure power and impedance (eg 114 and 116, respectively), each sensor is associated with that sensor, which results from the calibration performed on each sensor. It has an error function. By measuring power and impedance using a single sensor 214, only one calibration is done and therefore little error is introduced.

0024Second, having more sampling points can improve impedance measurements. In the art, sampling can typically be initiated only after a change in pulse or generator waveform has been detected, but herein the local controller 212 is referred to as the first sensor 214. , Indicates the start of a pulse or generator 202 waveform change before or at that point. Therefore, the first sensor 214 can start sampling earlier than is possible in the art and thus allow for more accurate impedance measurements.

0025Third, the measurement of impedance depends on the frequency of the signal being measured, and therefore the error in measuring the frequency leads to the error in the impedance being measured. Conventional impedance measurements are often made after a sensor in the matched network (eg, 116) has measured the frequency, thus introducing unnecessary error. As an alternative, when using a wideband sensor, an error is introduced by analog variation within the wideband sensor as a function of frequency. Rather than requiring the first sensor 214 to measure frequencies in a matched network (eg 104), the first sensor 214 is made aware of the frequencies produced by the generator 202. The sensor 214 of 1 experiences almost no error in impedance measurement than the sensor in the prior art. Also, the first sensor 214 does not need to measure the frequency, so more samples can be taken, and a larger sample size improves accuracy.

0026Fourth, because each component in the power delivery system (eg, generator 202, first sensor 214, matching network 204, optional second sensor 218) is different, the operating parameters of the power delivery system are: Preferably, it is adjusted when different components are replaced. Traditional power supplies do not consider variations between components. In contrast, the local controller 212 recognizes the various components of the power delivery system 200 and adjusts its instructions to the generator 202 and the matching network 204 as appropriate.

0027Component variation can be taken into account by identifying components to the local controller 212. For example, the generator 202 and the matching network 204 can identify themselves to the local controller 212 via brand, model, serial number, or other identifying information. It can also provide operating characteristics such as status, setting points, and configuration, to name a few. This can be done via the RF engine 213 and the impedance control system 215, respectively. The first sensor and the second sensors 214, 218 can also identify themselves to the local controller 212. Authentication can be done via an authentication algorithm. Thus, in one embodiment, only certain types or brands of generator 202 and matched network 204 are operational when connected via transmission medium 208. The local controller 212 can also query the generator 202, the matched network 204, and the sensors 214, 218 to determine its unit type, serial number, part number, or any other identification information. With this knowledge, the local controller 212 coordinates the instructions to the generator 202 and the matching network 204 and takes into account variations within the components, thus making the power delivery system 200 more accurate and more accurate than possible in the art. It can be made possible to provide consistent power.

0028The power delivery system 100 also improves the consistency (or quality) of power delivery due to its ability to measure both power and impedance. In part, consistency is improved through the higher accuracy mentioned above (eg, reduced error accumulation and earlier and wider sampling). Whereas prior art has been difficult to maintain stability within multiple control loops of a power delivery system, a single controller 214 controls multiple control loops for stability and synchronization between the control loops. Consistency is also improved because it can be ensured.

0029Some design aspects enable these advantages. The first is the use of a single sensor 214 to monitor both the power output of generator 202 and the impedance experienced by generator 202. The first sensor 214 can measure voltage, current, phase, impedance, and power at the output of generator 202. The first sensor 214 can be located at the output of the generator 202. The ability of the first sensor 214 to measure impedance remotely allows it to measure the impedance experienced by the generator 202 in addition to the power from the generator 202, which is not possible in the art. It is a feature. The remote impedance measurement is at a location physically remote (or calibration point) from the first sensor 214, eg, at a physical distance along the first transmission medium 208 from the first sensor 214 (or a calibration point). For example, check the impedance at the input of the matching network 204).

0030Inaccuracies in traditional impedance measurements meant that remote monitoring of impedances was difficult, if not impossible. There are two reasons why the first sensor 214 overcomes these challenges: (1) The first sensor 214 has a higher voltage standing wave ratio associated with calibration impedance than sensors in the art. In contrast, (2) the first sensor 214, which has a better linear response, can measure the phase of the generator 202 output power more precisely.

0031Typically, the sensor can be configured to operate optimally near the central operating impedance (eg, 50Ω), but due to its non-linear response to impedance fluctuations, the sensor moves away from the calibration impedance. Accuracy deteriorates sharply. This inaccuracy for physically localized measurements is amplified when making measurements over large physical distances. In contrast, sensor 214 has a better linear response on the voltage standing wave ratio circle, allowing accurate impedance measurements of impedances away from impedance calibration points, and thus physically at remote locations.

0032In addition, the first sensor 214 can measure the phase of the output of the generator 202 more precisely than was possible with previous generation sensors. Especially at high phase angles, it is extremely sensitive to phase angle measurement accuracy and therefore to the resulting impedance and power measurements. Since the first sensor 214 can measure the phase angle more accurately, the impedance can be measured better remotely.

0033In one embodiment, the first sensor 214 is a directional coupler. The directional coupler can measure the scaled power of forward and reverse power and the phase difference between them. The directional coupler can then return the scaled power and phase differences to the local controller 212. The scaled power is the voltage that the directional coupler provides to the measurement system and is proportional to the output voltage of the generator 202 operating under its nominal load condition (eg 50Ω).

0034Secondly, the aforementioned advantages are made possible by the integrated control and monitoring of the power delivery system 200 through a single local controller 212. The local controller 212 can receive and analyze information from the generator 202, the matching network 204, the first sensor 214, and the optional second sensor 218. The local controller 212 may invoke one or more algorithms, analyze the information received about the power delivery system 200, and determine the steps to be taken to ensure consistent power delivery to the plasma load 206. The local controller 212 may also issue commands to other components within the power delivery system 200, such as the generator 202 and the matched network 204, to perform certain actions and procedures.

0035Much of the operator's responsibility is reduced as the local controller 212 monitors all measurements and delivers all control signals and instructions, and the speed at which the generator 202 and matching network 204 adapt to power and impedance fluctuations is reduced. It will be improved. Such a configuration also simplifies the hardware requirements of the power delivery system 200, as conductors and signal lines are rarely required. By minimizing the number of conductors and signal lines, the generator 202 and the matched network 204 can be controlled via smaller and less complex software and firmware.

0036The local controller 212 manages the operation of both the generator 202 and the matched network 204, allowing simultaneous tuning of their components. The local controller 212 can instruct the RF engine 213 of the generator 202 to adjust the amplitude, carrier frequency, power frequency, pulse width, pulse duty cycle, or waveform of the power output of the generator 202. The local controller 212 can also instruct the impedance control system 215 of the matching network 204 to adjust the impedance of the matching network 212, for example by having the motor drive board adjust the variable capacitors of the matching network 104. ..

0037The available tuning options can dictate how the local controller 212 manages the power delivery system 200. If the frequency of the generator 202 is fixed, the local controller 212 can pass the instructions to the matching network 204 and adjust the impedance. If the frequency of the generator 202 is variable, the local controller 212 (1) passes the instructions to the matching network 204 to change the impedance experienced by the generator 202, and (2) passes the instructions to the generator 202. and, changing the power output frequency, or (3) pass to the matching network 204 an instruction to change the impedance of the generator 202 experiences, life passed decree to the generator 202, change its power output frequency can do. Since the frequency of the generator 202 is adjusted more quickly than the impedance of the matched network 204, it is configured to tune to the generator 202 over the frequency in addition to or instead of adjusting the impedance of the matched network 204. That may be preferable when high speed tuning is required. In other words, impedance matching can be done via simultaneous tuning of the generator 202 and the matching network 204.

0038More consistent and accurate power can be delivered if the local controller 212 takes into account the information provided by the optional second sensor 218. For example, the optional second sensor 218 provides data that characterizes the power delivered to the plasma load 206, so that the local controller 212 more accurately and consistently aligns the tuning instructions with the generator 202. It can be made possible to provide to network 204. Measurements from the optional second sensor 218 are also used for chamber matching and can improve consistent power delivery between chambers operating in parallel (each chamber has a different power delivery system). ). The local controller 212 also uses these measurements to improve consistency between wafers, uniform processing across wafer surfaces, end point detection (eg, through monitoring of light emission from the plasma), and arc management. Can be done. Although not shown, in some embodiments, the optional second sensor 218 can be placed in the plasma chamber or in contact with the wafer.

0039In certain embodiments, the power provided to the plasma load 206 can be varied for various set points (eg, from a first set point to a second set point). The matched network 204 may not be adjustable fast enough to maintain consistent power delivery to the plasma load 206 if the generator 202 switches between power set points. To overcome this challenge, a test run can be used to determine the preferred matching network 204 setpoints corresponding to each generator 202 setpoint. The commissioning occurs before the element, semiconductor, or any other object to be processed is installed in the plasma chamber. The matching network 204 and the generator 202 are then tuned to the set points of the various generator 202. Parameters that can be tuned include the frequency of the generator 202, the pulse width, and the impedance of the matching network 204. This tuning is performed without any involvement in the chamber so that slow tuning can occur without harming the elements in the chamber. The parameters determined to be preferable for the set points of the various generators 202 can be stored in memory. During the actual plasma processing, the local controller 212 can issue commands to the generator 202 and the matching network 204 to operate with the preferred parameters associated with the various setpoints. In this way, the matching network 204 and the generator 202 do not need to be tuned during processing, but rather can be quickly set to the preferred parameters as determined by the test run.

0040The local controller 212 can also consider the following non-limiting aspects that characterize the power delivery system 200: component efficiency characteristics, control algorithm parameters, variable capacitor positions within the matching network 204, failures and warnings, etc. Diagnostic, component health criteria, component history logs, and component status requests.

0041The local controller 212 can also take into account the non-electrical characteristics of the plasma load 206 when managing the operation of the generator 202 and the matched network 204. For example, the local controller 212a may include, to name a few non-limiting examples, the chamber pressure, the chemistry of the gas in the chamber, the ion energy of the plasma, the light intensity of the plasma, the spectral components of the light emitted by the plasma, And plasma arc discharge can be considered. In one embodiment, the optional second sensor 218 is emitted by the chamber pressure, the chemical properties of the gas in the chamber, the ion energy of the plasma, the light intensity of the plasma, the plasma, to name a few non-limiting examples. The spectral components of the light produced and the non-electrical properties of the plasma load 206 or plasma processing chamber (not shown) such as plasma arc discharge can be monitored.

0042As shown, the local controller 212 is a single conduit for user interaction with the power delivery system 200. In one embodiment, the user can interface with an external controller 220 that communicates with the local controller 212. User control of the generator 202 and the matched network 204 is performed via the external controller 220 and via the local controller 212. However, those skilled in the art will recognize that user interaction with the power delivery system is not necessarily limited to the local controller 212.

0043The first sensor 214 can optionally be implemented with the optional second sensor 218 (or load sensor). The optional second sensor 218 can be located at the output of the matching network 204 (218a) or at some location (218b) between the matching network 204 and the plasma load 206 and containing them. The optional second sensor 218 is configured to characterize the power delivered to the plasma load 206, the output of the matching network 204 or the voltage, anywhere between the matching network 204 and the plasma load 206. Current, phase, impedance, or power can be measured. In certain embodiments, the optional second sensor 218 can be coupled to the plasma load 206 and can be coupled into the plasma processing chamber or to the wafer during processing.

0044The local controller 212 is itself and these between the generator 202 (particularly the RF engine 213), the first sensor 214, the matching network 204 (particularly the impedance control system 215), and the optional second sensor 218. It is possible to manage communication between components and between these components and users (eg, via an external controller 220). These communications are via signal paths 225a or 225b inside the generator 202 and the matching network 204, respectively, or generally outside the generator 202 and the matching network 204 (but inside the generator 202 and the matching network 204, respectively). It can be done via the signal path 226 (which can include part of).

0045In the illustrated embodiment, the signal path 226 is a bus (the signal can travel in both directions and multiple signals can travel along the same path). However, in other embodiments, the various components can have their own signal path to the local controller 212. In other embodiments, there can be more than one bus type signal path, and in yet other embodiments, it can be a combination of bus-like and non-bus signal paths.

0046In some embodiments, the signal path 226 can be replaced by a signal via the transmission medium 208. In other words, the communication from the optional second sensor 218 to the local controller 212 can be modulated on the power signal transmitted between the generator 202 and the matching network 204. Communication between the various components illustrated can be via a serial communication protocol such as RS-485. Alternatively, one or more of these communications can be made over a wireless connection or over a wired or wireless network. For example, signal path 226 can be implemented as a local area network (LAN).

0047Referring to FIG. 2b, the local controller 212b is located within the power delivery system 200, but is not part of or connected to the generator 202 or the matching network 204. The local controller 212b can communicate with various components via the signal path 226, which is configured as a bus. Again, the bus configuration is not mandatory and each component can have a separate signal path to the local controller 212b.

0048In FIG. 2c, the local controller 212c is attached to, or is part of, the consistent network 204. Again, any combination of bus-type signal paths or separated signal paths can be used. As shown, the optional second sensor 218 and impedance control system 215 at the first position 218a can communicate with the local controller 212c via the signal path 625b inside the matching network 204. The generator 202 (particularly the RF engine 213), the first sensor 214, and the optional second sensor 218 at the alternative position 218b communicate with the local controller 212c via the signal path 226 in the bus configuration.

0049The local controller 212, RF engine 213, first sensor 214, impedance control system 215, and optional second sensor 218 are, but not limited to, a central processing unit (CPU), field programmable gate array (FPGA), programmable logic. It can include any processor, such as an element (PLD), a digital signal processor (DSP), or a combination of one or more CPUs, FPGAs, PLDs, and / or DSPs. Any of these components can include or communicate with its own memory or shared memory, in which case the memory is the power transmitted to the configuration of generator 202 and matching network 204 or plasma load 206. It can be configured to store information such as the tendency of. The memory can be part of the local controller 212, or can be part of either the generator 202 or the matched network 204. In certain embodiments, the memory can be part of the RF engine 213 or impedance control system 215.

0050The local controller 212 may include hardware, software, firmware, or a combination thereof. For example, the local controller 212 analyzes the data from the first sensor and the second sensors 214, 218 and instructs the generator 202 and the matching network 204 to adjust the internal parameters of their components. And can include processors, memory, and software running on the processor that are configured to determine when to instruct.

0051The RF engine 213, the first sensor 214, the impedance control system 215, and the optional second sensor 218 can each contain logic such as a processor that receives instructions and transmits information to the local controller 212. Alternatively, the local controller 212 can handle all logic and control functions for each of the RF engine 213, the first sensor 214, the impedance control system 215, and the optional second sensor 218.

0052Power delivery requirements can be programmed within the local controller 212, reside in memory accessible by the local controller 212, or be provided by the user (user power delivery requirements). In certain embodiments, the first sensor and the second sensors 214, 218 are either VI sensors (which can measure voltage, current, and phase) or directional couplers which can measure phase. In practice, only one of the two second sensor 218 positions (218a or 218b) is implemented.

0053Transmission media 208, 210 can be implemented as high power cables or transmission lines. They can also be electrical connections between the adjacent or connected generator 202 and the matching network 204. In one embodiment, the generator 202 is aligned as part of the integrated power delivery system 200, such that the transmission medium 208 is simply an internal electrical connection between the two subcomponents of the power delivery system 200. Connected to network 204. In another embodiment, the generator 202 and the matching network 204 are interconnected so that the transmission medium 208 is absent. In other words, the generator 202 and the matching network 204 can be part of a single box, container, package, or unit. Such an embodiment may involve greater integration of sub-components (eg, power supply, memory, and processor, to name a few) and communication between the generator 202 and the matching network 204. Several subcomponents within the generator 202 and the matching network 204 can be shared. For example, the matching network 204 can be made like an integral part of the generator 202, where both the generator 202 and the matching network 204 can share the filter and / or final coupler of the generator 202.

0054In certain embodiments, the power control system can include a local controller 212, a first sensor 214, and optionally a second sensor 218. Power control systems can be used to modify existing power delivery systems and improve their power delivery capabilities, as described above.

0055FIG. 3 illustrates an embodiment of a multiple generator power delivery system 300. The power delivery system 300 provides matched networks 304a, 304b, 304c, each of which is used to minimize the reflected power as the generators 302a, 302b, 302c provide power to the plasma load 306. Includes three generators 302a, 302b, 302c that accompany. Sensors 314a, 314b, 314c are included to monitor the voltage, current, phase, impedance, and power of generators 302a, 302b, 302c. Sensors 314a, 314b, 314c are part of each generator 302a, 302b, 302c, or are connected to each generator 302a, 302b, 302c, or outside each generator 302a, 302b, 302c. There can be. Sensors 314a, 314b, 314c relay voltage, current, phase, power, and impedance measurements to the local controller 312.

0056Sensors 314a, 314b, 314c can also relay to the local controller 312 their own identification, including information such as configuration and operating parameters. The generators 302a, 302b, 302c and the matched networks 315a, 315b, 315c also themselves to the local controller 312 via, for example, RF engines 313a, 313b, 313c and impedance control systems 315a, 315b, 315c, respectively. Can be identified.

0057The local controller 312 can manage communication between generators 302a, 302b, 302c, matched networks 304a, 304b, 304c, and sensors 314a, 314b, 314c. The local controller 312 is also configured to pass instructions on how and when to adjust internal parameters to the generators 302a, 302b, 302c and the matching networks 304a, 304b, 304c. In this way, the local controller 312 operates so that the generators 302a, 302b, 302c and the matched networks 304a, 304b, 304c are integrated and take into account variations between components and the behavior of other components. Allows you to. In some cases, this integrated operation of the power delivery system 300 can also take into account non-electrical factors such as the chemistry of the plasma chamber gas or the processing endpoint. In certain embodiments, the frequencies of the generators 302a, 302b, 302c can be tuned while also tuning the matching networks 304a, 304b, 304c.

0058In this multiple generator embodiment, each generator 302a, 302b, 302c recognizes another generator 302a, 302b, 302c through a transmission medium 310a, 310b, 310c or a plasma load 306 (depending on the configuration). A particular challenge in the art is consistent power generation. In other words, conventional multiple generator systems are plagued by crosstalk interactions between generators 302a, 302b, 302c. The generators 302a, 302b, 302c and the matching networks 304a, 304b, 304c communicate with each other via the local controller 312 and are controlled by the local controller 312, taking into account the operation of all of these components. At the same time, consistent and accurate power can be provided to the plasma load 306.

0059In certain embodiments, the user can interface with an external controller 320 that communicates with the local controller 312. The external controller 320 can send and receive both instructions and data to and from the local controller 412. User control of the generators 302a, 302b, 302c and the matched networks 304a, 304b, 304c is performed via the external controller 320 and via the local controller 312.

0060The local controller 312 is illustrated as part of generator 302a, but can also be part of generator 302b or generator 302c. Alternatively, any other location within the power delivery system 300 can also be used.

0061In addition, the local controller 312 can communicate with the RF engines 313a, 313b, 313c of each generator 302a, 302b, 302c and the impedance control systems 315a, 315b, 315c of each matching network 304a, 304b, 304c. In particular, the local controller 312 can communicate with these subcomponents and pass instructions. Thus, the local controller 312 modifies operating parameters such as pulse frequency and variable capacitor position for generators 302a, 302b, 302c and matched networks 304a, 304b, 304c, to name two non-limiting examples. Can be ordered.

0062FIG. 4 illustrates another embodiment of the multiple generator power delivery system 400. FIG. 4 differs from FIG. 3 in that the sensors 414a, 414b, 414c are located at the outputs of the matching networks 404a, 404b, 404c instead of the generator outputs 402a, 402b, 402c. Sensors 414a, 414b, 414c each generator 402a by measuring voltage, current, phase, impedance, and / or power at the output of the matched network 404a, 404b, 404c, or on the way to the plasma load 406. , 402b, 402c and the matching networks 404a, 404b, 404c are configured to characterize the power.

0063The sensors 414a, 414b, 414c and the generators 402a, 402b, 402c can identify themselves to the local controller 412 via the RF engine and impedance control systems 415a, 415b, 415c, respectively.

0064The power delivery system 400 can interface with the user via an external controller 420. The external controller 420 can communicate with the local controller 412 and send and receive both instructions and data to and from the local controller 412.

0065As in the embodiments described above, the local controller 412 is, as illustrated, as part of the generator 402a, or as part of any of the other components within the power delivery system 400, or. Adjacent to any of these components, it can still be located within the power delivery system 400.

0066Impedance control systems 415a, 415b, 415c are illustrated for each matching network 404a, 404b, 404c, but those skilled in the art will appreciate that these are separate hardware (or software or firmware) components, or each matching. You will recognize that it can represent any single hardware component that has separate logical blocks for networks 404a, 404b, 404c. In an alternative embodiment, a single impedance control system (not shown) can control the operating parameters of all three matched networks 404a, 404b, 404c.

0067In another embodiment, the sensors 414a, 414b, 414c can be replaced by a single sensor located between the matched networks 404a, 404b, 404c and the plasma load 406. A single sensor can measure voltage, current, phase, impedance, and power so that the three sensors 414a, 414b, 414c shown are configured.

0068The generators 402a, 402b, 402c and the matched networks 404a, 404b, 404c are illustrated to communicate with the local controller 412 via the same signal path (in a bus configuration), but in other embodiments, each The component may have a separate signal path to the local controller. Alternatively, the generators 402a, 402b, 402c may have one signal path to the local controller 412, while the matched networks 404a, 404b, 404c have another signal path to the local controller 412. Sensors 414a, 414b, 414c can also have their own signal path to the local controller 412.

0069FIG. 5 illustrates yet another embodiment of the multiple generator power delivery system 500. FIG. 5 differs from FIGS. 3 and 4 in that the sensors in those figures are replaced here by a single sensor 514 arranged as the input of the plasma load 506. The sensor 514 is configured to characterize the power for each generator 502a, 502b, 502c and the matched network 504a, 504b, 504c.

0070The power delivery system 500 can interface with the user via an external controller 520. The external controller 520 can communicate with the local controller 512 and send and receive both instructions and data to and from the local controller 512.

0071The generators 502a, 502b, 502c and the matched networks 504a, 504b, 504c are illustrated to communicate with the local controller 512 via the same signal path (in a bus configuration), but in other embodiments, each The component may have a separate signal path to the local controller. Alternatively, the generators 502a, 502b, 502c may have one signal path to the local controller 512, while the matched networks 504a, 504b, 504c have another signal path to the local controller 512. Sensors 514a, 514b, 514c can also have their own signal path to the local controller 512.

0072Each external controller in Figure 3-5 is illustrated to have their own signal path to the local controller, but in an alternative embodiment, each external controller is used by a sensor generator and the matching network is local. It can share the same signal path used to communicate with the controller.

0073The multiple generator illustrated in Embodiment 3-5 shows three sets of generator, matched network, and sensor, but in other embodiments, these configurations are of generator, matched network, and sensor. It can be implemented by two or more pairs. In one embodiment, there can be a single sensor instead of one for each set of generators and matching networks. A single sensor can measure power output locally to one generator and remotely to two generators. A single sensor can also remotely characterize the impedance for all three matched networks.

0074FIG. 6 illustrates a method 600 of supplying power to a plasma load according to an embodiment of the present disclosure. Method 600 includes monitoring operation 602, analysis operation 604, and relay operation 606. Monitoring operation 602 involves monitoring the electrical characteristics of the power output of a generator (eg, 202) and providing the electrical characteristics of the power output to a local controller (eg, 212). The analysis operation 604 can include analyzing the electrical characteristics of the power output (eg, voltage, current, phase, impedance, power). Analytical operation 604 can also involve determining how the power delivery system (eg, 200) can be operated in light of the monitored electrical characteristics to meet the power delivery requirements. Relay operation 606 can involve relaying (passing or transmitting) instructions to the generator and matched network of the power delivery system, in which case the instructions can be based on analytical operation 604. Instructions can allow simultaneous tuning of generators and matching networks.

0075The systems and methods described herein can be implemented in machines such as computer systems, in addition to the specific physical elements described herein. FIG. 7 is an exemplary embodiment of a computer system 700 in which a set of instructions can be executed to cause an element to perform or perform any one or more of the aspects and / or methodologies of the present disclosure. A schematic representation of an embodiment of the machine is shown. The components in FIG. 7 are examples only, and the use or functionality of any hardware, software, embedded logic component, or combination of two or more such components that implement a particular embodiment. It is not limited to the range of.

0076The computer system 700 may include a processor 701, a memory 703, and a storage device 708 that communicate with each other and with other components via the bus 740. The bus 740 also includes a display 732, one or more input elements 733 (which may include, for example, a keypad, keyboard, mouse, stylus, etc.), one or more output elements 734, one or more storage elements 735, and various types. Tangible storage medium 736 can be linked. All of these elements can be interfaced directly or via one or more interfaces or adapters to the bus 740. For example, the various tangible storage media 736 can interface with the bus 740 via the storage medium interface 726. Computer system 700 includes one or more integrated circuits (ICs), printed circuit boards (PCBs), mobile handheld elements (such as mobile phones or PDA), laptop or notebook computers, distributed computer systems, computing grids, or It can have any suitable physical form, including, but not limited to, servers.

0077Processor 701 (or Central Processing Unit (CPU)) optionally includes cache memory unit 702 for temporary local storage of instructions, data, or computer addresses. Processor 701 is configured to assist in the execution of computer-readable instructions. The computer system 700 functions as a result of the processor 701 executing software embodied in one or more tangible computer-readable storage media such as memory 703, storage device 708, storage element 735, and / or storage medium 736. Can provide sex. A computer-readable medium may store software that implements a particular embodiment, and processor 701 may execute the software. The memory 703 may read software from one or more other computer-readable media (mass storage elements 735, 736, etc.) or from one or more other sources through a suitable interface such as network interface 720. The software may cause the processor 701 to perform one or more processes or one or more of the processes described or illustrated herein. Implementation of such a process or thing may include defining a data structure stored in memory 703 and modifying the data structure as directed by the software.

0078The memory 703 is, but is not limited to, a random access memory component (eg, RAM704) (eg, static RAM "SRAM", dynamic RAM "DRAM", etc.), a read-only component (eg, ROM705), and any. It may include various components (eg, machine-readable media), including combinations thereof. The ROM 705 may act unidirectionally to communicate data and instructions with the processor 701, and the RAM 704 may act bidirectionally to communicate data and instructions with the processor 701. The ROM 705 and RAM 704 may include any suitable tangible computer readable medium described below. In one embodiment, a basic input / output system 706 (BIOS) containing basic routines, which is useful for transferring information between elements in computer system 700, such as during boot, is stored in memory 703. obtain.

0079The fixed storage device 708 is optionally connected to the processor 701 bidirectionally through the storage control unit 707. Fixed storage 708 provides additional data storage capacity and may also include any suitable tangible computer-readable medium described herein. Storage 708 can be used to store operating system 709, EXEC710 (executable files), data 711, APV application 712 (application program), and equivalents. In many cases, but not always, the storage device 708 is a secondary storage device medium (such as a hard disk) that is slower than the primary storage device (eg, memory 703). The storage device 708 can also include an optical disk drive, a solid-state memory element (eg, a flash-based system), or a combination of any of the above. The information in storage 708 may, where appropriate, be incorporated as virtual memory in memory 703.

0080In one embodiment, the storage element 735 may be removably interfaced with the computer system 700 (eg, via an external port connector (not shown)) via the storage element interface 725. In particular, the storage element 735 and associated machine-readable media may provide non-volatile and / or volatile storage devices for machine-readable instructions, data structures, program modules, and / or other data for the computer system 700. .. In one embodiment, the software may reside entirely or partially in a machine-readable medium on the storage element 735. In another embodiment, the software may reside entirely or partially within processor 701.

0081Bus 740 connects various subsystems. As used herein, references to buses may optionally include one or more digital signal lines that perform a common function. Bus 740 is of several types of bus structures, including, but not limited to, memory buses, memory controllers, peripheral buses, local buses, and any combination thereof that uses any of a variety of bus architectures. It can be either. As an example, but not limited to, such architectures include Industry Standard Architecture (ISA) Bus, Extended ISA (EISA) Bus, Micro Channel Architecture (MCA) Bus, Video Electronics Standards Association Local Bus (VLB), Peripheral Component Interconnect. (PCI) Bus, PCI-Express (PCI-X) Bus, Accelerated Graphics Port (AGP) Bus, Hyper Transport (HTX) Bus, Serial Advanced Technology Attachment (SATA) Bus, and any combination of them. Be done.

0082The computer system 700 may also include input element 733. In one embodiment, a user of computer system 700 may input commands and / or other information into computer system 700 via input element 733. Examples of the input element 733 include an alphanumeric input element (eg, keyboard), a pointing element (eg, mouse or touchpad), a touchpad, joystick, gamepad, audio input element (eg, microphone, voice response system, etc.). , Optical scanners, moving or still image capturing elements (eg, cameras), and any combination thereof, but not limited to them. Input element 733 is via any of a variety of input interfaces 723 (eg, input interface 723), including, but not limited to, serial, parallel, gameport, USB, FIREWIRE, THUNDERBOLT, or any combination described above. An interface can be taken for bus 740.

0083In certain embodiments, when the computer system 700 is connected to the network 730, the computer system 700 may communicate with other elements, specifically mobile elements and enterprise systems connected to the network 730. Communication to and from computer system 700 may be transmitted through network interface 720. For example, network interface 720 may receive incoming communications (requests or responses from other elements, etc.) from network 730 in the form of one or more packets (such as Internet Protocol (IP) packets) and computer system 700. Can store incoming communications in memory 703 for processing. Similarly, the computer system 700 may store in memory 703 outgoing communications (requests or responses to other elements, etc.) that are communicated from network interface 720 to network 730 in the form of one or more packets. .. Processor 701 may access these communication packets stored in memory 703 for processing.

0084Examples of the network interface 720 include, but are not limited to, network interface cards, modems, and any combination thereof. Examples of network 730 or network segment 730 include wide area networks (WANs) (eg Internet, corporate networks), local area networks (LANs) (eg offices, buildings, campuses, or other relatively small geographic spaces. (Networks associated with), telephone networks, direct connections between two computing elements, and any combination thereof, but not limited to them. Networks such as Network 730 may employ wired and / or wireless communication modes. In general, any network topology can be used.

0085Information and data can be displayed through display 732. Examples of the display 732 include, but are not limited to, a liquid crystal display (LCD), an organic liquid crystal display (OLED), a cathode ray tube (CRT), a plasma display, and any combination thereof. The display 732 can interface with the processor 701, the memory 703, and the fixed storage device 708, as well as other elements such as the input element 733, via the bus 740. The display 732 is linked to the bus 740 via the video interface 722, and the transfer of data between the display 732 and the bus 740 can be controlled via the graphic control 721.

0086In addition to the display 732, the computer system 700 may include one or more other peripheral output elements 734, including, but not limited to, audio speakers, printers, and any combination thereof. Such peripheral output elements may be connected to bus 740 via output interface 724. Examples of the output interface 724 include, but are not limited to, serial ports, parallel connections, USB ports, FIREWIRE ports, HUNDERBOLT ports, and any combination thereof.

0087In addition, or as an alternative, the computer system 700 performs one or more of the one or more processes described or illustrated herein on behalf of or in conjunction with the software. Functionality may be provided as a result of a wired connection in the circuit or logic embodied otherwise, which may behave as such. References to software in the present disclosure may include logic, and references to logic may include software. Further, a reference to a computer-readable medium may optionally include a circuit (such as an IC) that stores software for execution, a circuit for embodying logic for execution, or both. The present disclosure includes any suitable combination of hardware, software, or both.

0088In conclusion, the present invention provides systems and methods for providing consistent and accurate power to a plasma load, especially for plasma processing when power generation and chamber conditions are dynamic. Some advantages of the systems and methods disclosed herein include chamber matching, chamber characterization, chamber diagnostics, chamber failure prediction, and troubleshooting. To those skilled in the art, numerous variations and substitutions have been made in the present invention, its uses, and its configurations in order to achieve substantially the same results as those achieved by the embodiments described herein. It is easy to recognize what can be done. Therefore, there is no intention to limit the present invention to the disclosed exemplary forms. Many variations, modifications, and alternative structures are within the scope and spirit of the disclosed invention as set forth in the claims.