Protection system for switches in direct drive circuit of substrate processing system

Abstract

SOLUTION: To provide a direct drive system for providing RF power to a component of a substrate processing system, which includes a direct drive circuit including a switch and configured to supply RF power to the component, and provide a switch protection module configured to monitor a load current and a load voltage in a processing chamber, calculate a load resistance on the basis of the load current and the load voltage, compare the load resistance to a first predetermined load resistance, and adjust at least one of an RF power limit and an RF current limit of the direct drive circuit on the basis of the comparison.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a substrate processing system, and more particularly to a drive circuit for supplying RF plasma power or RF bias in a substrate processing system.

Background Art

[0002] The background description provided herein is for the purpose of generally presenting the content of the present disclosure. The research of the presently named inventors, to the extent described in this background art section, is not admitted as prior art to the present disclosure, whether explicitly or implicitly, in the same manner as aspects of the specification that may not qualify as prior art at the time of filing in another form.

[0003] Substrate processing systems are typically used to etch thin films on substrates such as semiconductor wafers. Etching usually involves either wet chemical etching or dry etching. Dry etching can be performed using a plasma generated by inductively coupled plasma (ICP). The inductively coupled plasma can be generated by a coil disposed outside the processing chamber adjacent to a dielectric window. A process gas flowing through the processing chamber is ignited to generate a plasma. In some applications, RF plasma power is output to one or more induction coils disposed outside the processing chamber. Also, RF bias power can be supplied to the electrodes of the substrate support.

[0004] Additional process control can be achieved by changing the frequency of the RF plasma power or RF bias power. Further, additional process control can be achieved by changing the magnitude or level of the RF plasma power or RF bias power during processing. Changes in the RF plasma power or level, and / or the RF bias power or level can change the impedance seen from the drive circuit. When an impedance mismatch occurs between the load and the drive circuit, power is reflected and inefficient.

Summary of the Invention

[0005] A direct drive system for providing RF power to components of a substrate processing system includes a switch and a direct drive circuit configured to supply RF power to the components. A switch protection module monitors a load current and a load voltage in a processing chamber, calculates a load resistance based on the load current and the load voltage, compares the load resistance with a first predetermined load resistance, and is configured to adjust at least one of an RF power limit and an RF current limit of the direct drive circuit based on the comparison.

[0006] As another feature, a voltage / current (VI) probe is disposed in the processing chamber and configured to generate a load current and a load voltage. The first predetermined load resistance is selected based on a resistance in at least one non-plasma state. At least one non-plasma state corresponds to a non-ignition of plasma. At least one non-plasma state corresponds to a disappearance of plasma after a process gas flow to the processing chamber is stopped.

[0007] In another feature, in response to the load resistance being less than or equal to the first predetermined load resistance, the switch protection module reduces at least one of an RF power limit and an RF current limit of the direct drive circuit. The switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period longer than a predetermined period. In response to the load resistance being less than or equal to the first predetermined load resistance, the switch protection module increases at least one of an RF power limit and an RF current limit of the direct drive circuit.

[0008] In another feature, the switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period longer than a predetermined period.

[0009] In other features, the switch protection module selects at least one of the first RF power limit and the first RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selects at least one of the second RF power limit and the second RF current limit of the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance. At least one of the first RF power limit and the first RF current limit of the direct drive circuit is less than at least one of the second RF power limit and the second RF current limit of the direct drive circuit. The switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period longer than a predetermined period.

[0010] In other features, the switch protection module selects at least one of the first RF power limit and the first RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selects at least one of the second RF power limit and the second RF current limit of the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance. At least one of the first RF power limit and the first RF current limit of the direct drive circuit is greater than at least one of the second RF power limit and the second RF current limit of the direct drive circuit. The switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period longer than a predetermined period.

[0011] In other features, the switch protection module is configured to shut down the direct drive circuit in response to the load resistance being below a first predetermined load resistance for a period longer than a predetermined period. The direct drive circuit includes a clock generator for generating a clock signal of a first frequency and a gate driver for receiving the clock signal. The bridge circuit includes a first switch having a control terminal connected to the gate driver, a first terminal, and a second terminal. The second switch has a control terminal connected to the gate driver, a first terminal connected to the second terminal of the first switch and an output node, and a second terminal.

[0012] In other features, a current sensor senses the current at the output node and generates a current signal. A voltage sensor senses the voltage at the output node and generates a voltage signal. The controller includes a phase offset calculation module for calculating the phase offset between the voltage signal and the current signal and a clock adjustment module for adjusting the first frequency based on the phase offset. The component includes a coil disposed outside the processing chamber.

[0013] A method for providing RF power to components of a substrate processing system includes supplying RF power to the components using a direct drive circuit including a switch, monitoring the load current and load voltage in the processing chamber, calculating the load resistance based on the load current and load voltage, comparing the load resistance with a first predetermined load resistance, and adjusting at least one of the RF power limit and the RF current limit of the direct drive circuit based on the comparison.

[0014] In other features, the method includes disposing a voltage / current (VI) probe in the processing chamber and using the VI probe to generate the load current and the load voltage. The first predetermined load resistance is selected based on the resistance in at least one non-plasma state. At least one non-plasma state corresponds to the plasma not being ignited.

[0015] At least one non-plasma state corresponds to the plasma disappearing after the process gas flow to the processing chamber is stopped.

[0016] In other features, the method includes reducing at least one of the RF power limit and the RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance. The method includes shutting down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period longer than a predetermined period.

[0017] In other features, the method further includes increasing at least one of the RF power limit and the RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance. The method further includes shutting down the direct drive circuit when the load resistance is less than the first predetermined load resistance for a period longer than a predetermined period.

[0018] In other features, the method includes selecting at least one of a first RF power limit and a first RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selecting at least one of a second RF power limit and a second RF current limit of the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance. At least one of the first RF power limit and the first RF current limit of the direct drive circuit is less than at least one of the second RF power limit and the second RF current limit of the direct drive circuit. The method includes shutting down the direct drive circuit in response to the load resistance being less than the first predetermined load resistance for a period longer than a predetermined period.

[0019] In other features, the method includes selecting at least one of a first RF power limit and a first RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selecting at least one of a second RF power limit and a second RF current limit of the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance. At least one of the first RF power limit and the first RF current limit of the direct drive circuit is greater than at least one of the second RF power limit and the second RF current limit of the direct drive circuit. The method includes shutting down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period longer than a predetermined period.

[0020] Further applicable areas of the present disclosure will become apparent from the detailed description, the claims, and the drawings. The detailed description and the specific examples are for illustrative purposes only and are not intended to limit the scope of the present disclosure.

Brief Description of the Drawings

[0021] The present disclosure will be more fully understood from the detailed description and the accompanying drawings.

[0022]

Figure 1A

[0023]

Figure 1B

[0024]

Figure 2

[0025]

Figure 3

[0026]

Figure 4

[0027]

Figure 5

[0028]

Figure 6

[0029]

Figure 7

Figure 8

[0030]

Figure 9

[0031]

Figure 10

[0032] In the drawings, reference numbers may be reused to identify similar and / or identical elements.

DETAILED DESCRIPTION OF THE INVENTION

[0033] In some applications, the frequency of the RF source power supplied to the ICP coil and / or the RF bias to the electrodes of the substrate support are switched between two or more frequencies and / or two or more pulse levels. In these systems, the impedance of the RF generator is matched to the load (such as the induction coil and plasma, or the electrode and plasma, etc.). However, the impedance of the load varies due to changes in the plasma state, changes in the pulse level, and / or various other factors. When impedance mismatch occurs, power is reflected at the load and is inefficient. Tuning a circuit using a variable capacitor is difficult due to the amount of time required to change the capacitance value for the switching period between frequency changes and / or level changes.

[0034] To address some of the problems identified above, instead of an RF source and a matching network, a direct drive circuit including a switch has been used to supply RF power. Examples of direct drive circuits and hybrid direct drive circuits are shown and described in commonly assigned U.S. Patent No. 10,515,781, which is hereby incorporated by reference in its entirety. Since the direct drive circuit operates at a low impedance, it solves the matching problems as described above.

[0035] When there is no plasma, such as when the plasma does not ignite or disappears after the gas flow is stopped, the switch of the direct drive circuit may fail. To protect the direct drive circuit, RF current limits and loss limits have been used. However, the RF current limit alone does not solve switch failures at higher RF frequencies, such as 13 MHz. Reducing the loss limit can prevent switch failures, but the operating window is also reduced to an unacceptable level. Also, the loss limit is not well understood and the accuracy is not sufficient.

[0036] The systems and methods according to the present disclosure monitor the load voltage and current during the operation of a direct drive circuit using a voltage (V)-current (I) probe (VI probe) disposed in a processing chamber. The load resistance is calculated from the measured voltage and current and compared to a predetermined resistance threshold. In some examples, if the measured load resistance is less than the predetermined resistance threshold, a switch protection module modifies the operation of the direct drive circuit. More specifically, if the load resistance is less than the predetermined resistance threshold, reduced RF power limits and / or RF current limits are applied until the load resistance changes. The load resistance increases when a transition occurs from a non-plasma state to a plasma-on state.

[0037] In another example, if the load resistance is less than the predetermined resistance threshold in a non-plasma state, increased RF power limits and / or RF current limits are applied for a predetermined period to attempt to strike a plasma. This approach is counterintuitive because the normal way to protect a switch is to reduce power. However, when a plasma is struck in response to higher RF power and / or current limits, the load resistance generally increases because a transition occurs from a non-plasma state to a plasma-on state.

[0038] After the plasma is turned on, the power limits and / or current limits can be increased (if the limits were reduced due to a low load resistance) or decreased (if the limits were increased due to a low load resistance). In some examples, if the low load resistance condition persists for a predetermined time, the system sends an error message (or activates an alarm) and shuts off the output RF power from the direct drive circuit.

[0039] Referring now to FIGS. 1A and 1B, an example of a substrate processing system 10 according to the present disclosure is shown. The substrate processing system 10 includes one or more RF direct drive systems 52, which are further described below.

[0040] In some examples, a plenum 20 may be disposed between the coil 16 and the dielectric window 24 to control the temperature of the dielectric window 24 with warm air and / or cold air. The dielectric window 24 is disposed along one side of the processing chamber 28. The processing chamber 28 further includes a substrate support (or pedestal) 32. The substrate support 32 may include an electrostatic chuck (ESC), or may include a mechanical chuck or other types of chucks. A process gas is supplied to the processing chamber 28, and plasma 40 is generated inside the processing chamber 28. The plasma 40 etches the exposed surface of the substrate 34. Also, an RF bias may be provided to the electrodes in the substrate support 32 during operation using another RF direct drive system 52 (such as those further described below).

[0041] To supply a process gas mixture to the processing chamber 28, a gas supply system 56 may be used. The gas supply system 56 may include a process gas / inert gas source 57, a gas metering system 58 such as valves and mass flow controllers, and a manifold 59. A gas supply system 60 may be used to supply a gas 62 to the plenum 20 via a valve 61. This gas may include a cooling gas (air) used to cool the coil 16 and the dielectric window 24. A heater / cooler 64 may be used to heat / cool the substrate support 32 to a predetermined temperature. The exhaust system 65 includes a valve 66 and a pump 67 for removing reactants from the processing chamber 28 by purge or discharge.

[0042] A controller 54 may be used to control the etching process. The controller 54 monitors system parameters and controls the supply of the gas mixture, the collision, maintenance, and extinction of the plasma, the removal of reactants, the supply of the cooling gas, etc.

[0043] The VI probe 92 is disposed in the processing chamber and senses the load voltage and current. As can be seen from FIG. 1B, the direct drive system 52 includes a controller 93 having a switch protection module 94. In some examples, the controllers 54 and 93 can be combined. The direct drive circuit 95 includes a bridge circuit 96 and a switch 98. The switch protection module 94 protects the switch 98 by calculating the load resistance based on the load voltage and load current and then adjusting the operation of the direct drive system 52 based on the load resistance. More specifically, the switch protection module 94 compares the load resistance with a predetermined resistance threshold. If the measured load resistance is less than the predetermined resistance threshold, the switch protection module 94 changes the operation of the direct drive circuit 95.

[0044] In some examples, when the load resistance is less than a predetermined resistance threshold, a reduced RF power limit and / or an RF current limit is applied until the load resistance increases. The load resistance increases due to the transition from a non-plasma state to a plasma-on state. In other examples, when the load resistance is less than a predetermined resistance threshold, an increased RF power limit and / or an RF current limit is applied until the load resistance increases due to the plasma state. The direct drive system 52 includes a bridge circuit 96 and one or more switches modulated to generate RF power.

[0045] Now, referring to FIG. 2, an example of the direct drive circuit 95 for supplying RF bias (or RF plasma power) is shown. The direct drive circuit 95 includes a clock 120 operating at one or more selected RF frequencies. The clock signal output by the clock 120 is input to the gate driver circuit 122. In some examples, the gate driver circuit 122 includes an amplifier 144 and an inverting amplifier 146 each having an input connected to the clock 120.

[0046] The output of the gate driver circuit 122 is input to the bridge circuit 138. In some examples, the bridge circuit 138 includes a first switch 140 and a second switch 142 (corresponding to the switch 98 to be protected). In some examples, the first switch 140 and the second switch 142 include metal-oxide-semiconductor field-effect transistors (MOSFETs). The first switch 140 and the second switch 142 each include a control terminal, and first and second terminals. The output of the amplifier 144 of the gate driver circuit 122 is input to the control terminal of the first switch 140. The output of the inverting amplifier 146 of the gate driver circuit 122 is input to the control terminal of the second switch 142.

[0047] The output node 130 is connected to the second terminal of the first switch 140 and the first terminal of the second switch 142. The first terminal of the first switch 140 is connected to the DC power supply 126. The second terminal of the second switch 142 is connected to a reference potential such as ground. The output node 130 is connected to a coil or inductor by a capacitor 132.

[0048] The direct drive circuit of FIG. 2 uses a single DC power supply 126 that may generate unwanted DC voltage / components on the base plate of the ESC. This DC component can complicate the wafer chucking / de-chucking performance by affecting the ESC DC bias on the base plate that is expected to be independently controlled.

[0049] Referring now to FIG. 3, the Fourier transform of the voltage waveform at the output node 130 of the bridge circuit 138 in FIG. 2 can be expressed in the form of an equation as follows.

Equation

[0050] Here, referring to FIG. 4, in order to remove unnecessary DC voltage on the base plate, the direct drive circuit 95 may use a dual DC power supply. The direct drive circuit 95 includes a first DC power supply 410 operating at +V DC / 2 and a second DC power supply 420 operating at -V DC / 2. To achieve the same output RF power, both the first and second DC power supplies 410 and 420 operate at half the voltage of the single DC power supply in FIG. 2. In some examples, the first DC power supply 410 and the second DC power supply 420 operate with substantially the same magnitude and opposite polarities. As used herein, substantially the same means that the difference in the magnitude of the DC voltage output by the first DC power supply 410 with respect to the second DC power supply 420 is less than 10%, less than 5%, or less than 1%. The first DC power supply 410 is connected to the first terminal of the first switch 140. The second DC power supply 420 is connected to the second terminal of the second switch 142.

[0051] Here, referring to FIG. 5, the voltage waveform output by the direct drive circuit 95 in FIG. 4 has no DC component in the following Fourier transform.

Equation

[0052] Here, referring to FIG. 6, the direct drive circuit 95 includes the clock 120, gate driver circuit 122, bridge circuit 138, first DC power supply 410, and second DC power supply 420 described above. The output node 130 is connected to the coil by a capacitor 132.

[0053] The current sensor 640 is connected to the output node 130. Similarly, the voltage sensor 642 is connected to the output node 130. The sensed current output by the current sensor 640 and the sensed voltage output by the voltage sensor 642 are input to a controller 644 that includes a phase offset calculation module 646 and a clock frequency adjustment module 648.

[0054] The phase offset calculation module 646 determines the phase offset between the voltage and the current. The phase offset calculation module 646 outputs the phase offset to the clock frequency adjustment module 648. When the voltage leads the current, the clock frequency adjustment module 648 decreases the frequency of the clock 120. When the current leads the voltage, the clock frequency adjustment module 648 increases the frequency of the clock 120. In some examples, hysteresis may be used. In some examples, when the voltage leads the current by a predetermined first threshold TH1, the clock frequency adjustment module 648 decreases the frequency of the clock 120. In some examples, when the voltage leads the current by a predetermined second threshold TH2, the clock frequency adjustment module 648 decreases the frequency of the clock 120.

[0055] Here, referring to FIG. 7, a method 700 for controlling a direct drive circuit is shown. At 710, the waveforms of the current and the voltage are sensed at the output node or another location. At 714, the phase offset is determined between the waveforms of the voltage and the current. For example, the zero crossings of the current and the voltage can be monitored. The phase offset can be determined using the difference in the timing of the zero crossings. At 720, the frequency of the clock is adjusted to reduce the phase offset between the voltage and the current.

[0056] Here, referring to FIG. 8, a method 800 for adjusting the frequency of a clock is shown. If the voltage leads the current as determined at 810, the frequency is decreased at 820. In some examples, before the frequency is decreased, the voltage needs to lead the current by more than a first threshold value TH1. If the current leads the voltage as determined at 830, the frequency is increased at 840. In some examples, before the frequency is increased, the current needs to lead the voltage by more than a second threshold value TH2. In other examples, hysteresis is not used.

[0057] Here, referring to FIG. 9, a method 900 for protecting a switch of a direct drive circuit of a substrate processing system is shown. At 914, the method determines whether the direct drive circuit is on or supplying RF power. If it is false, the method returns to 914. If 914 is true, the method proceeds to 918 and monitors the load voltage and load current. In some examples, the load voltage and load current are monitored using a VI probe. At 922, the load resistance is calculated based on the load voltage and load current. At 926, the load resistance is compared with a predetermined resistance threshold R th If the load resistance is less than the predetermined resistance threshold R th the method reduces the RF power and / or RF current of the direct drive circuit to protect the switch at 932.

[0058] At 938, the method determines whether the timer is on. If 938 is false, the timer is turned on at 948. At 942, the value of the timer is compared with a predetermined period t TH If the value of the timer is less than the predetermined period t TH3 the method proceeds to 914. If the value of the timer is greater than or equal to the predetermined period t TH3 the method proceeds to 946 and shuts down the direct drive circuit. In some examples, an error message is sent and / or an alarm is activated.

[0059] Here, referring to FIG. 10, instead of reducing the RF power limit and / or the RF current limit, the RF power limit and / or the RF current limit can be increased at 1010 to 1014 for a predetermined period t TH4 and an attempt can be made to cause the plasma to collide. When the plasma collides, the resistance measured by the VI probe generally also increases. If the plasma is not caused to collide within the predetermined period t TH4 , the direct drive circuit is shut down as described above.

[0060] The following is an example for illustrative purposes only, and other parameters can be used. For example, when protecting the switch using the maximum power and the loss, the maximum power at 2 MHz can be set to 6 kW, and the maximum power at 13 MHz can be set to 3 kW. The maximum RF current at 2 MHz rms can be set to 150 A (a +15% headroom (or 172.5 A rms ) can be used for transient currents with a duration of 0.05 seconds to 2 seconds). The maximum RF current at 13 MHz rms can be set to 90 A (a +15% headroom (or 103.5 A rms )) for transient currents with a duration of 0.05 seconds to 2 seconds). The loss limits at 2 MHz and 13 MHz are 1500 W and 1200 W respectively. Even when these limits were used, the switch failed. As a result, the limits were reduced and the operating window was unacceptably narrowed.

[0061] As described above, problems may occur when the RF direct drive circuit is operating in the non-plasma state power mode. At 2 MHz, the internal resistance is equal to 16.25 mΩ in a 4-channel design, and the switch can have a drain-source resistance R DS (On) of 65 mΩ. At 13 MHz, the internal resistance is equal to 60 mΩ in a 4-channel design, and the switch can have a drain-source resistance R DS (On) of 240 mΩ.

[0062] A typical non-plasma load at 2 MHz is 5 mΩ. A typical plasma load at 13 MHz is 70 mΩ. The RF power efficiency in the non-plasma state is quite low (when other internal stray losses are not considered). For example, at 2 MHz, the efficiency is 5 / (5 + 16.25) = 23.53%. At 13 MHz, the efficiency is 70 / (70 + 60) = 53.85%. The approximate maximum internal RF power consumption of the power switch when other internal stray switching losses are not considered is as follows. At 2 MHz, I 2 2MHz R 2MHz = 110 2 × 0.01625 = 196.625 (W). At 13 MHz, I 2 13MHz R 13MHz = 90 2 × 0.06 = 486 (W).

[0063] The limit of the minimum load resistance for protection purposes is set higher than the nominal non-plasma load resistance. A typical non-plasma load resistance at 2 MHz is equal to about 5 mΩ (maximum RF power of 60.5 W for a maximum RF current of 110 A rms ). A typical non-plasma load resistance at 13 MHz is equal to about 70 mΩ (maximum RF power of 567 W for a maximum RF current of 90 A rms ).

[0064] The load resistance is monitored when the RF is turned on. When the minimum load resistance is detected during normal operation, the switch protection module turns off the RF output power and / or reduces the output power until it is lower than the safe limit. For example, multipliers K 2 and K 13 can be used (i.e., K 2 × 60.5 W 2MHz , K 13 × 567 W 13MHz can be used, where K 2 and K 13 are adjustable parameters ranging from 0 to 1).

[0065] If a minimum load resistance is detected during ignition or a transition of the processing step, the switch protection module stops the RF output power control if it is operating in the power mode, and reduces or holds the DC rail to a level low enough so that the RF current stays within its safety limits (i.e., K 2 ×110A 2MHz and K 13 ×90A 13MHz , where K 2 and K 13 are configurable parameters ranging from 0 to 1).

[0066] If this state persists for longer than a predetermined period, the switch protection module cuts off the RF power and sends an alarm. In some examples, the predetermined period ranges from 5 milliseconds to 1 second.

[0067] The foregoing description is merely illustrative in nature and is not intended to limit the present disclosure, its application, or uses. The broad teachings of the present disclosure can be implemented in a variety of forms. Accordingly, while the present disclosure includes specific examples, upon review of the drawings, the specification, and the following claims, other modifications will become apparent, and the true scope of the present disclosure should not be so limited. It should be understood that one or more steps within a method may be performed in a different order (or simultaneously) without changing the principles of the present disclosure. Further, each embodiment has been described as having specific features, but any one or more of those features described with respect to any embodiment of the present disclosure may be implemented in and / or combined with the features of any other embodiment even if the combination is not explicitly described. That is, the described embodiments are not mutually exclusive, and swapping one or more embodiments with each other remains within the scope of the present disclosure.

[0068] Spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.) are described using various terms such as "connection", "engagement", "coupling", "adjacency", "neighboring", "above", "on top of", "below", and "arrangement". Unless explicitly stated to be "direct", when a relationship between a first and a second element is described in the above disclosure, the relationship may be a direct relationship with no other intervening elements between the first and second elements, but may also be an indirect relationship with one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the expression "at least one of A, B, and C" should be interpreted to mean the logic (A or B or C) using non-exclusive logical OR, and should not be interpreted to mean "at least one of A, at least one of B, and at least one of C".

[0069] In some implementations, the controller is part of the system and may be part of the above-described embodiments. Such a system can include semiconductor processing equipment including single or multiple processing tools, single or multiple chambers, single or multiple processing platforms, and / or specific processing components (such as wafer pedestals, gas flow systems, etc.). These systems may be integrated with electronic devices for controlling the operation of the system before, during, and after processing of a semiconductor wafer or substrate. This electronic device may sometimes be referred to as a "controller" that can control various components or sub-parts of a single or multiple systems. The controller may be programmed to control any of the processes disclosed herein, such as supply of process gases, temperature setting (e.g., heating and / or cooling), pressure setting, vacuum setting, power setting, setting of radio frequency (RF) generators, setting of RF matching circuits, frequency setting, flow rate setting, liquid supply setting, position and motion setting, loading and unloading of wafers to and from tools, and loading and unloading of wafers to and from other transfer tools and / or load locks connected or interlocked with a specific system, depending on the processing requirements and / or the type of the system.

[0070] In a broad sense, the controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software, etc., which receives commands, issues commands, controls operations, enables cleaning operations, and enables endpoint measurements. The integrated circuit may include a chip in the form of firmware that stores program instructions, digital signal processors (DSPs), chips defined as application-specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions may be instructions transmitted to the controller in the form of various individual settings (or program files) that define operating parameters for executing a specific process on or for a semiconductor wafer or for a system. The operating parameters may, in some embodiments, be part of a recipe defined by a process engineer to achieve one or more processing steps during the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or patterns of the wafer.

[0071] In some implementations, the controller may be part of a computer that is integrated with, connected to, or otherwise network-connected to the system, or a combination thereof, or may be connected to such a computer. For example, the controller may be within the "cloud" or within all or part of a fab host computer system that enables remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of manufacturing operations, investigate the history of past manufacturing operations, investigate trends or performance criteria from multiple manufacturing operations, change the parameters of the current process, set the process steps following the current process, or initiate a new process. In some examples, a remote computer (e.g., a server) may provide a processing recipe to the system via a network that may include a local network or the Internet. The remote computer may include a user interface that enables input or programming of parameters and / or settings, which are then transmitted from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify the parameters of each processing step executed during one or more operations. It should be understood that the parameters may be specific to the type of process being executed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller may be distributed, such as by consisting of one or more separate controllers network-connected to each other, acting towards a common purpose such as the processing and control described herein. Examples of such purpose-distributed controllers include one or more integrated circuits on a chamber that communicate with one or more remotely located integrated circuits (such as at the platform level or as part of a remote computer) and are combined to control the process on the chamber.

[0072] Although not limited, exemplary systems may include a plasma etching chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a clean chamber or module, a bevel edge etching chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etching (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing system related to or that may be used in the assembly and / or manufacture of semiconductor wafers.

[0073] As described above, depending on the single or multiple processing steps performed by the tool, the controller may communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, the main computer, other controllers, or tools used for material transport that convey the wafer container inside and outside the load port within the semiconductor manufacturing factory and / or at the tool location.

Claims

1. 1. A direct drive circuit for providing RF power to a component of a substrate processing system, comprising: a direct drive circuit including a switch and configured to provide RF power to the component; monitoring load current and load voltage within the processing chamber; Calculating a load resistance based on the load current and the load voltage; comparing the load resistance to a first predetermined load resistance; adjusting at least one of an RF power limit and an RF current limit of the direct drive circuit based on the comparison; A switch protection module configured as a direct drive circuit.

2. 2. The direct drive circuit of claim 1, further comprising a voltage / current (VI) probe disposed in the processing chamber and configured to generate the load current and the load voltage.

3. 2. The direct drive circuit of claim 1, wherein the first predetermined load resistance is selected based on a resistance in at least one non-plasma condition.

4. 4. The direct drive circuit of claim 3, wherein the at least one non-plasma state corresponds to a plasma not igniting.

5. 4. The direct drive circuit of claim 3, wherein the at least one no-plasma condition corresponds to a plasma being extinguished after process gas flow to the processing chamber is stopped.

6. 2. The direct drive circuit of claim 1 , wherein in response to the load resistance being less than or equal to a first predetermined load resistance, the switch protection module reduces at least one of the RF power limit and the RF current limit of the direct drive circuit.

7. 7. The direct drive circuit of claim 6, wherein the switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for greater than a predetermined period of time.

8. 2. The direct drive circuit of claim 1, wherein in response to the load resistance being less than or equal to the first predetermined load resistance, the switch protection module increases at least one of the RF power limit and the RF current limit of the direct drive circuit.

9. 9. The direct drive circuit of claim 8, wherein the switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for greater than a predetermined period of time.

10. 2. The direct drive circuit of claim 1, the switch protection module selects at least one of a first RF power limit and a first RF current limit for the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selects at least one of a second RF power limit and a second RF current limit for the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance; at least one of a first RF power limit and a first RF current limit of the direct drive circuitry is less than at least one of a second RF power limit and a second RF current limit of the direct drive circuitry; and the switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period of time greater than a predetermined period. Direct drive circuit.

11. 2. The direct drive circuit of claim 1, the switch protection module selects at least one of a first RF power limit and a first RF current limit for the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selects at least one of a second RF power limit and a second RF current limit for the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance; at least one of a first RF power limit and a first RF current limit of the direct drive circuitry is greater than at least one of a second RF power limit and a second RF current limit of the direct drive circuitry; and the switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period of time greater than a predetermined period. Direct drive circuit.

12. 2. The direct drive circuit of claim 1, wherein the switch protection module is configured to shut down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period of time greater than a predetermined period.

13. 2. The direct drive circuit of claim 1, a clock generator for generating a clock signal at a first frequency; a gate driver for receiving the clock signal; a bridge circuit, The bridge circuit includes a first switch having a control terminal connected to the gate driver, a first terminal, and a second terminal; a second switch having a control terminal connected to the gate driver, a first terminal connected to the second terminal of the first switch and an output node, and a second terminal; a direct drive circuit.

14. 14. The direct drive circuit of claim 13, a current sensor that senses a current at the output node to generate a current signal; a voltage sensor that senses a voltage at the output node and generates a voltage signal; A controller, the controller includes a phase offset calculation module for calculating a phase offset between the voltage signal and the current signal; a clock adjusting module for adjusting the first frequency based on the phase offset; a direct drive circuit.

15. 15. The direct drive circuit of claim 14, wherein the component comprises a coil located outside the processing chamber.

16. 1. A method for providing RF power to a component of a substrate processing system, comprising: providing RF power to the component using a direct drive circuit including a switch; monitoring a load current and a load voltage in the processing chamber; calculating a load resistance based on the load current and the load voltage; performing a comparison of the load resistance to a first predetermined load resistance; adjusting at least one of an RF power limit and an RF current limit of the direct drive circuit based on the comparison; A method comprising:

17. 17. The method of claim 16, further comprising: disposing a voltage / current (VI) probe in the processing chamber; and generating the load current and the load voltage using the VI probe.

18. 17. The method of claim 16, wherein the first predetermined load resistance is selected based on a resistance in at least one non-plasma condition.

19. 20. The method of claim 18, wherein the at least one non-plasma state corresponds to a plasma not igniting.

20. 20. The method of claim 18, wherein the at least one non-plasma state corresponds to plasma being extinguished after process gas flow to the processing chamber is stopped.

21. 17. The method of claim 16, further comprising: reducing at least one of the RF power limit and the RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance.

22. 22. The method of claim 21, further comprising: in response to the load resistance being less than or equal to the first predetermined load resistance for a period of time greater than a predetermined period, shutting down the direct drive circuit.

23. 17. The method of claim 16, further comprising: increasing at least one of the RF power limit and the RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance.

24. 24. The method of claim 23, further comprising shutting down the direct drive circuit if the load resistance is less than the first predetermined load resistance for greater than a predetermined period of time.

25. 17. The method of claim 16 further comprising: selecting at least one of a first RF power limit and a first RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selecting at least one of a second RF power limit and a second RF current limit of the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance; at least one of a first RF power limit and a first RF current limit of the direct drive circuitry is less than at least one of a second RF power limit and a second RF current limit of the direct drive circuitry; shutting down the direct drive circuit in response to the load resistance being less than the first predetermined load resistance for a period of time greater than a predetermined period. method.

26. 17. The method of claim 16 further comprising: selecting at least one of a first RF power limit and a first RF current limit of the direct drive circuit in response to the load resistance being less than or equal to a first predetermined load resistance, and selecting at least one of a second RF power limit and a second RF current limit of the direct drive circuit in response to the load resistance being greater than the first predetermined load resistance; at least one of a first RF power limit and a first RF current limit of the direct drive circuitry is greater than at least one of a second RF power limit and a second RF current limit of the direct drive circuitry; shutting down the direct drive circuit in response to the load resistance being less than or equal to the first predetermined load resistance for a period greater than a predetermined period. method.

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