Radio frequency generation device and arc detection device

Abstract

The invention provides a radio frequency generation device and an arc detection device. In one embodiment, the radio frequency generating device comprises: a radio frequency power supply configured to output a radio frequency power signal to a plasma cavity; the current sensor is arranged between the radio frequency power supply and the plasma cavity and is used for detecting the current of the plasma in the cavity and generating a current signal; the voltage sensor is arranged between the radio frequency power supply and the plasma cavity and is used for detecting the voltage of the plasma in the cavity and generating a voltage signal; and the electric arc detection device is configured to receive the current signal and the voltage signal and generate an electric arc generation signal when the value of the current signal is out of a current threshold range and the value of the voltage signal is out of a voltage threshold range. The device has a voltage and current dual judgment mechanism, and the accuracy of arc detection in the plasma cavity is improved.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor equipment, and in particular to a radio frequency generating device and an arc detecting device. Background Art

[0002] Plasma processing is often used in semiconductor manufacturing. In plasma processing, electrical energy is usually used to provide the energy required to excite the plasma. When the electrical energy is supplied, abnormal accumulation of charges may occur due to defects in the electrode plates, close distances, and other issues, thus forming arc discharge. This abnormal arc discharge will generate a large local current, burning the devices in the cavity and the products to be processed.

[0003] When an RF power supply is used to provide high-frequency AC energy, the current and voltage measured at the output end of the RF power supply differ greatly from the current and voltage in the plasma chamber, making it difficult to accurately judge arc discharge. One solution is to measure the reflection coefficient at the output end of the RF power supply. When the reflection coefficient rises above the threshold within a certain range, an arc is judged to have occurred. The principle of this judgment is that when the RF energy is stably transmitted to the plasma load, the reflection coefficient should remain low. When an arc occurs, the sudden change in energy will cause a mismatch in the RF transmission, that is, the reflection coefficient increases. However, this method cannot judge the occurrence of an arc when the RF outputs energy in a pulsed manner, because when the pulse signal is output, the power jumps back and forth between two values, and a high reflection coefficient will inevitably appear at the switching moment. The above method cannot correctly judge whether an arc or a pulse switching occurs.

[0004] Therefore, with the development of semiconductor equipment and components, it is necessary for the RF generator to accurately determine the arc occurrence event in the cavity during both continuous power output and pulse power output. Summary of the invention

[0005] The embodiments of the present application provide a radio frequency generating device and an arc detecting device, which are intended to solve the problems existing in arc detection in the existing plasma chamber.

[0006] In a first aspect, an embodiment of the present application provides a radio frequency generating device, which includes: a radio frequency power supply, configured to output a radio frequency power signal to a load in a plasma chamber; a current sensor, arranged between the radio frequency power supply and the plasma chamber, for detecting the current of the load in the chamber and generating a current signal; a voltage sensor, arranged between the radio frequency power supply and the plasma chamber, for detecting the voltage of the load in the chamber and generating a voltage signal; and an arc detection device, configured to receive the current signal and the voltage signal, and when the current signal value is outside the current threshold range and the voltage signal value is outside the voltage threshold range, generate an arc occurrence signal indicating that an arc has occurred in the chamber.

[0007] Optionally, the arc detection device is configured to generate an arc occurrence signal indicating that an arc has occurred in the cavity when the current signal value is higher than an upper current threshold and the voltage signal value is lower than a lower voltage threshold.

[0008] Optionally, the arc detection device includes a current sampling module, which is configured to sample the current signal to generate a fast sampling current signal and a slow sampling current signal; the current threshold range is between an upper current threshold and a lower current threshold, wherein the upper current threshold is the slow sampling current signal value plus the current threshold, and the lower current threshold is the slow sampling current signal value minus the current threshold; the arc detection device is also configured to determine whether the fast sampling current signal value is within the current threshold range.

[0009] Optionally, the arc detection device includes a voltage sampling module, which is configured to sample the voltage signal to generate a fast-sampling voltage signal and a slow-sampling voltage signal; the voltage threshold range is between an upper voltage threshold and a lower voltage threshold, wherein the upper voltage threshold is the slow-sampling voltage signal value plus the voltage threshold, and the lower voltage threshold is the slow-sampling voltage signal value minus the voltage threshold; the arc detection device is also configured to determine whether the fast-sampling voltage signal value is within the voltage threshold range.

[0010] Optionally, the arc detection device is further configured to receive the current signal generated by the current sensor and the voltage signal generated by the voltage sensor after the plasma excited by the radio frequency power signal in the cavity reaches a stable state.

[0011] Optionally, the RF power supply is further configured to receive the arc occurrence signal to suspend outputting the RF power signal to the plasma chamber.

[0012] Optionally, the RF power supply device also includes a controller, which is configured to receive the arc occurrence signal and time the arc occurrence time based on the arc occurrence signal, and generate a control signal to control the RF power supply to output the RF power signal within an additional process time, wherein the additional process time is equal to the arc occurrence time.

[0013] Optionally, the RF power supply is further configured to send a pulse synchronization signal to the arc detection device; and the arc detection device is further configured to receive the current signal and the voltage signal when the pulse synchronization signal indicates that the pulse is turned on.

[0014] Optionally, the arc detection device is further configured to receive the current signal and the voltage signal after the plasma excited by the radio frequency power signal in the cavity reaches a stable state.

[0015] Optionally, the current sensor and the voltage sensor are arranged on a side close to an electrode or an inductor coil in the plasma chamber.

[0016] In a second aspect, an embodiment of the present application provides an arc detection device for connecting to a current sensor and a voltage sensor, wherein the current sensor is arranged between the RF power supply and the plasma chamber, and is used to detect the current of the load in the chamber and generate a current signal; the voltage sensor is arranged between the RF power supply and the plasma chamber, and is used to detect the voltage of the load in the chamber and generate a voltage signal; the RF power supply is configured to output an RF power signal to the load in the plasma chamber, wherein the arc detection device is configured to receive the current signal and the voltage signal, and when the current signal value is outside the current threshold range and the voltage signal value is outside the voltage threshold range, generate an arc occurrence signal indicating that an arc has occurred in the chamber.

[0017] Optionally, the arc detection device is configured to generate an arc occurrence signal indicating that an arc has occurred in the cavity when the current signal value is higher than an upper current threshold and the voltage signal value is lower than a lower voltage threshold.

[0018] Optionally, the arc detection device includes a current sampling module, which is configured to sample the current signal to generate a fast sampling current signal and a slow sampling current signal; the current threshold range is between an upper current threshold and a lower current threshold, wherein the upper current threshold is the slow sampling current signal value plus the current threshold, and the lower current threshold is the slow sampling current signal value minus the current threshold; the arc detection device is also configured to determine whether the fast sampling current signal value is within the current threshold range.

[0019] Optionally, the arc detection device includes a voltage sampling module, which is configured to sample the voltage signal to generate a fast-sampling voltage signal and a slow-sampling voltage signal; the voltage threshold range is between an upper voltage threshold and a lower voltage threshold, wherein the upper voltage threshold is the slow-sampling voltage signal value plus the voltage threshold, and the lower voltage threshold is the slow-sampling voltage signal value minus the voltage threshold; the arc detection device is also configured to determine whether the fast-sampling voltage signal value is within the voltage threshold range.

[0020] Optionally, the arc detection device is further configured to receive a pulse synchronization signal sent by the RF power supply, and when the pulse synchronization signal indicates that a pulse is on, receive a current signal generated by the current sensor and a voltage signal generated by the voltage sensor.

[0021] The above-mentioned RF generating device utilizes a dual determination mechanism of voltage and current, which can effectively improve the accuracy of arc detection in the plasma chamber. In addition, when judging whether an arc occurs, an adaptive mechanism of threshold is adopted. The electrical signal is double sampled, the slow sampling value is used to adjust the threshold range, and the fast sampling value is used to compare with the threshold range, so that when the power output state of the RF source changes or the external state changes, the real arc occurrence event can still be accurately identified. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0023] Figure 1 A schematic diagram of a radio frequency generating device provided in an embodiment of the present application is shown;

[0024] Figure 2 A schematic diagram of an arc detection device in a radio frequency generating device provided in an embodiment of the present application is shown;

[0025] Figure 3 A schematic diagram of a rule for judging the occurrence of an arc provided by an embodiment of the present application is shown;

[0026] Figure 4 A schematic diagram of a radio frequency generating device provided by another embodiment of the present application is shown; and

[0027] Figure 5 A timing diagram of a radio frequency power signal and a pulse synchronization signal output by a radio frequency power supply provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0028] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on another element or there can be one or more centered elements therebetween. When an element is described as "connected" to another element, it can be directly connected to another element or there can be one or more centered elements therebetween. The orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "bottom" and the like used in this specification is based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are used only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0029] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0030] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0031] Figure 1 Schematic diagram of a radio frequency generating device provided in an embodiment of the present application. Figure 1 As shown, the RF generating device includes an RF power supply 10, a current sensor 30, a voltage sensor 40 and an arc detection device 50. The RF generating device and the plasma processing part together constitute a plasma processing device. The RF power supply 10 generates an RF power signal and transmits the power signal to the input end of the sensor unit. The output end of the sensor unit is used to transmit the RF signal to the plasma processing part. The sensor unit may include one or more of a current sensor, a voltage sensor or a current and voltage sensor. In this embodiment, the sensor unit includes a current sensor 30 and a voltage sensor 40. The plasma processing part includes at least one plasma chamber 60, which has a plurality of loads therein, and these loads are used to receive the RF power signal generated by the RF power supply. In another embodiment, the plasma processing part may also include an RF transmission component, which is used to transmit the RF power to the plasma of the plasma chamber 60. The RF generating device can transmit the RF signal to the plasma chamber 60 directly or indirectly via an intermediate component.

[0032] The RF power source 10 provides an RF power signal to a load in the plasma chamber 60 to ignite plasma (or ignite plasma) in the plasma chamber 60 and maintain the plasma for wafer processing or chamber cleaning, etc. In some embodiments, the RF power source 10 can provide RF power of different frequencies.

[0033] The current sensor 30 is disposed between the RF power source 10 and the plasma chamber 60, and is used to detect the current signal of the load in the plasma chamber 60 and the scaling signal and / or filtering signal related to the current signal. The current sensor 30 can be an analog sensor or a digital sensor or a combination thereof. In a digital implementation, the current sensor 30 can include an analog-to-digital converter and a signal sampling component with a corresponding sampling rate. The current sensor 30 generates a current signal and transmits the signal to the arc detection device 50.

[0034] The voltage sensor 40 is disposed between the RF power source 10 and the plasma chamber 60, and is used to detect a voltage signal of a load in the plasma chamber 60 and a scaling signal and / or a filtering signal related to the voltage signal. The voltage sensor 40 may be an analog sensor or a digital sensor or a combination thereof. In a digital implementation, the voltage sensor 40 may include an analog-to-digital converter and a signal sampling component with a corresponding sampling rate. The voltage sensor 40 generates a voltage signal and transmits the signal to the arc detection device 50.

[0035] In one embodiment, the current sensor 30 and the voltage sensor 40 are arranged on one side close to the load in the plasma chamber 60 to accurately detect the electrical signal on the electrode or the inductive coil. In one embodiment, the current sensor 30 and the voltage sensor 40 are arranged on one side close to the upper electrode of the capacitively coupled plasma chamber or on one side of the coil of the inductively coupled plasma chamber. In another embodiment, the current sensor 30 and the voltage sensor 40 are arranged on one side close to the lower electrode of the capacitively coupled plasma chamber. In another embodiment, the current sensor 30 and the voltage sensor 40 can be integrated in the matching network 20 and close to one side of the upper electrode of the capacitively coupled plasma chamber or one side of the coil of the inductively coupled plasma chamber.

[0036] The arc detection device 50 receives the voltage signal from the voltage sensor 40 and the current signal from the current sensor 30. Based on the voltage signal and the current signal, the arc detection device 50 determines whether an arc event occurs in the cavity 60. When the current signal value is outside the current threshold range and the voltage signal value is outside the voltage threshold range, the arc detection device 50 generates an arc occurrence signal to indicate the occurrence of arc discharge.

[0037] The arc detection device adopts a dual judgment of voltage and current changes, that is, thresholds are set for the current signal and the voltage signal respectively, and when both exceed the thresholds at the same time, it is judged that an arc occurs. The advantage of this dual judgment is that it can prevent the interference of noise points on the arc judgment and can more accurately judge the occurrence of the arc. In addition, usually, when the plasma reaches a stable state, changing the RF power will not cause the reverse change of the voltage and current of the load in the cavity.

[0038] The load current and voltage before and after the plasma is generated in the plasma chamber are two states, and the present application focuses on arc detection after the generation. Therefore, in other embodiments, the arc detection device 50 is configured to receive current signals and voltage signals after the plasma excited in the cavity reaches a stable state. Specifically, when the RF power supply 10 outputs RF power, the voltage of the load (for example, the electrode plate) in the cavity will rise first, and when the plasma is generated, the load current will also quickly rise to a stable value. In this ignition stage, there will be fluctuations in voltage and current, and it is not appropriate to perform arc detection at this stage. A starting current threshold can be set. When the load current exceeds the starting current threshold, it is considered that the plasma has reached a stable state, and the arc detection device 50 starts arc detection.

[0039] The plasma processing part includes a plasma chamber 60, which is a plasma processing chamber that can be used for a variety of semiconductor processing steps, such as etching, deposition, cleaning, etc. The plasma chamber 60 has multiple loads. In some embodiments, the plasma chamber 60 includes a first load and a second load. The first load is connected to the RF power supply 10 via a cable to receive a RF power signal, and the second load is connected to another RF power supply via a cable to receive a RF power signal. The first load or the second load can be a capacitive load, such as an electrode plate. The first load can also be an inductive load, such as a coil. Therefore, the plasma chamber 60 can be any one of the following chambers: a capacitively coupled plasma (CCP) chamber, an inductively coupled plasma (ICP) chamber, a transformer coupled plasma (TCP) chamber, a through silicon via (TSV) chamber, and a remote plasma source (RPS) chamber.

[0040] In other embodiments, Figure 1As shown, the RF generating device also includes a matching network 20, which is arranged between the RF power supply 10 and the sensor unit (current sensor 30 and voltage sensor 40). The matching network 20 is used to match the output impedance of the RF power supply 10 with the input impedance of the plasma chamber 60. The input impedance can change with the frequency of the voltage applied by the RF power supply 10, the chamber pressure, the gas composition, and the target material or the substrate material. The matching network 20 includes electrical components such as variable capacitors and variable inductors, which are used to dynamically match the output impedance of the RF power supply 10 with the input impedance of the plasma chamber 60. Most RF power supplies have an output impedance of 50 ohms. The matching network 20 can adjust the mismatch between the input impedance and the output impedance (50 ohms) of the RF power supply. In addition, the matching network 20 may have one or more fixed impedances. Multiple fixed impedances correspond to the operating menus of multiple plasma processing devices.

[0041] Figure 2 A schematic diagram of an arc detection device provided in an embodiment of the present application. Figure 2 The arc detection device 50 is used as an example for illustration purposes only. Figure 2 As shown, the arc detection device includes a current sampling module 501 , a voltage sampling module 502 , a current judgment module 503 , a voltage judgment module 504 and a logic module 505 .

[0042] The current sampling module 501 is configured to receive the current signal sent by the current sensor 30, and perform fast sampling and slow sampling on the current signal to generate a fast sampling current signal 512 and a slow sampling current signal 513. Then, the current sampling module 501 feeds the fast sampling current signal 512 and the slow sampling current signal 513 to the current judgment module 503. In another embodiment, the current sampling module may include a fast current sampling module and a slow current sampling module to generate a fast sampling current signal 512 and a slow sampling current signal 513, respectively. As an example, the sampling rate of the fast sampling signal is 200ns, and the sampling rate of the slow sampling signal is 5us.

[0043] The current judgment module 503 is configured to receive a fast sampling current signal 512 and a slow sampling current signal 513 and a pre-set current threshold 514. The current judgment module 503 is also configured to set a current threshold range. The current threshold range includes an upper current threshold and a lower current threshold. Among them, the upper current threshold is the slow sampling current signal value plus the current threshold, and the lower current threshold is the slow sampling current signal value minus the current threshold. The current judgment module 503 is also configured to compare the fast sampling current signal value with the current threshold range to determine whether an arc occurs, and output a current arc signal 515 indicating the determination result accordingly. If the fast sampling current signal value is within the current threshold range, it is determined that no arc occurs; if the fast sampling current signal value is outside the current threshold range, it is determined that an arc occurs. The current arc signal 515 can be a logic signal indicating whether an arc occurs as determined by current detection. For example, the signal 515 can be a logic high signal indicating that an arc occurs, or a logic low signal indicating that an arc does not occur.

[0044] Usually, in the process of judging whether an arc occurs, the sampled value is compared with the threshold value. If the sampled value exceeds the threshold value, it is judged that an arc occurs. However, once the power or external state changes, if the previous threshold value is still maintained, it is easy to cause a false alarm of an arc. Fast sampling and slow sampling of the current signal can realize adaptive dynamic changes in the threshold setting. Specifically, the slow sampling value is used to calculate the current threshold or threshold range in the instantaneous cavity, and the fast sampling value is used to judge whether an arc occurs. Adding or subtracting the threshold value on the slow sampling value can determine the threshold range, and the threshold range can be used to accurately judge the occurrence of an arc more than a single threshold. If the actual output current changes, the threshold determined by the slow sampling value will also change accordingly, playing an adaptive role. The changing threshold range can effectively prevent false alarms of arcs. Because the sampling rate is slow, the fluctuation of abnormal data can be filtered out, and it can represent the reference current of the real-time state of the system. The fast sampling value can identify whether a real arc occurs by comparing it with the threshold range determined by the slow sampling value.

[0045] In some other embodiments, the current determination module 503 is configured to generate a current arc signal 515 of a logic high signal indicating the occurrence of an arc when the value of the fast-sampling current signal is higher than a current upper threshold.

[0046] In some other embodiments, the current determination module 503 is configured to generate a current arc signal 515 of a logic high signal indicating the occurrence of an arc when the value of the fast sampling current signal is lower than a current lower limit threshold.

[0047] The voltage sampling module 502 is configured to receive the voltage signal sent by the voltage sensor 40, and perform fast sampling and slow sampling on the voltage signal to generate a fast sampling voltage signal 522 and a slow sampling voltage signal 523. Then, the voltage sampling module 502 feeds the fast sampling voltage signal 522 and the slow sampling voltage signal 523 to the voltage determination module 504. In another embodiment, the voltage sampling module may include a fast voltage sampling module and a slow voltage sampling module to respectively generate a fast sampling voltage signal 522 and a slow sampling voltage signal 523. As an example, the sampling rate of the fast sampling signal is 200ns, and the sampling rate of the slow sampling signal is 5us.

[0048] The voltage judgment module 504 is configured to receive the fast sampling voltage signal 522 and the slow sampling voltage signal 523 and the pre-set voltage threshold 524. The voltage judgment module 504 is also configured to set a voltage threshold range. The voltage threshold range includes an upper voltage threshold and a lower voltage threshold. Among them, the upper voltage threshold is the slow sampling voltage signal value plus the voltage threshold, and the lower voltage threshold is the slow sampling voltage signal value minus the voltage threshold. The voltage judgment module 504 is also configured to compare the fast sampling voltage signal value with the voltage threshold range to determine whether an arc occurs, and output a voltage arc signal 525 indicating the determination result accordingly. If the fast sampling voltage signal value is within the voltage threshold range, it is determined that no arc occurs; if the fast sampling voltage signal value is outside the voltage threshold range, it is determined that an arc occurs. The voltage arc signal 525 can be a logic signal indicating whether an arc occurs as determined by voltage detection. For example, the signal 525 can be a logic high signal indicating that an arc occurs, or a logic low signal indicating that an arc does not occur.

[0049] In this way, similar to the current threshold, the setting of the voltage threshold can also achieve adaptive dynamic changes, thereby preventing false alarms of arcs and accurately identifying the occurrence of arcs.

[0050] In some other embodiments, the voltage determination module 504 is configured to generate a voltage arc signal 525 of a logic high signal indicating the occurrence of an arc when the value of the fast-sampling voltage signal is higher than a voltage upper threshold.

[0051] In some other embodiments, the voltage determination module 504 is configured to generate a voltage arc signal 525 of a logic high signal indicating the occurrence of an arc when the value of the fast-sampling voltage signal is lower than a voltage lower threshold.

[0052] The logic unit 505 may be configured to generate an arc signal 530 according to the current arc signal 515 and the voltage arc signal 525. In the present embodiment, the logic unit 505 may be an AND logic gate, and when the current arc signal 515 with a logic high signal and the voltage arc signal 525 with a logic high signal are received at the same time, the arc signal 530 with a logic high signal is generated to indicate that an arc has occurred in the cavity. In another embodiment, the logic unit 505 is an OR logic gate, and as long as any one of the current arc signal with a logic high signal and the voltage arc signal with a logic high signal is received, the arc signal 530 with a logic high signal is generated to indicate that an arc has occurred in the cavity.

[0053] Figure 3 The following is a schematic diagram of the judgment rule for arc occurrence provided by an embodiment of the present application. In this embodiment, during the duration of the arc discharge, the voltage on the cavity load (such as the electrode plate) is greatly reduced, and the corresponding current is greatly increased. Considering that changing the RF power can also cause changes in voltage and current, a dual judgment of voltage and current changes is adopted. Figure 4 As shown, the voltage signal value is the fast sampling voltage signal value, and the current signal value is the fast sampling current signal value. When the voltage signal value is lower than the voltage lower limit threshold, the voltage judgment module 504 generates a voltage arc signal 525 of a logic high signal. When the current signal value is higher than the current upper limit threshold, the current judgment module 503 generates a current arc signal 515 of a logic high signal. Finally, the logic unit 505 generates an arc signal 530 of a logic high signal.

[0054] Please refer back to Figure 1 The arc detection device 50 is configured to feed the generated arc occurrence signal to the RF power source 10. The RF power source 10 is also configured to stop outputting the RF power signal to the plasma chamber 60 when receiving the arc occurrence signal.

[0055] The arc detection device 50 may also be configured to feed the generated arc occurrence signal to other equipment. Figure 4 FIG. 2 shows a schematic diagram of a radio frequency generating device provided by another embodiment of the present application. Figure 1The difference between the RF generating device shown is that the RF generating device also includes a controller 70. The controller 70 is configured to receive the arc occurrence signal sent by the arc detection device 50, and send a control signal to the RF power supply 10 to control the RF power supply 10 to pause outputting the RF power signal to the plasma chamber 60. In another embodiment, further, the controller 70 is configured to receive the arc occurrence signal sent by the arc detection device 50, and count according to the logic high signal of the arc occurrence signal to time the arc occurrence time. Then, the controller 70 is configured to send a control signal to the RF power supply 10 to control the RF power supply 10 to increase a process time of outputting the RF power signal during the process, wherein the increased process time is equal to the arc occurrence time. In this way, the process time of suspending the output of the RF power signal due to the occurrence of the arc can be compensated in the entire process, so as to achieve the integrity of the processing process.

[0056] In another embodiment, the controller 70 may be integrated into the RF power source 10 to realize the function of supplementing the process time of suspending the output of the RF power signal due to the occurrence of the arc into the subsequent process.

[0057] It should be noted that Figure 1 , Figure 2 and Figure 4 The components or modules shown in the are divided based on functions, and the RF power supply, matching network, sensor, arc detection device, controller and other components or modules in the embodiments of the present application cannot be understood as separate physical hardware. In actual implementation, these components can be further combined or separated. For example, the functions of the arc detection device 50 or the controller 70 can be distributed in hardware, software and firmware components. One or more sensors can also be implemented by combining matching networks, RF power supplies or components in the cavity.

[0058] When the RF power source 10 outputs a pulse power signal, the arc detection device 50 is configured to determine whether an arc occurs only when the pulse is turned on. Figure 1 as well as Figure 5 The RF power source 10 outputs a pulsed RF power signal to the plasma chamber 60 and also outputs a pulsed RF synchronization signal to the arc detection device 50. Figure 5As shown, from time t0 to time t1, the RF power supply 10 outputs a sinusoidal RF power signal, and the pulse synchronization signal is a logic high level, corresponding to the pulse output. From time t1 to time t2, the RF power supply 10 does not output an RF power signal, and the pulse synchronization signal is a logic low level, corresponding to the pulse off. The arc detection device 50 is configured to receive the current and voltage signals only at a logic high level after receiving the pulse synchronization signal, and complete the sampling and arc judgment operations; and when the pulse synchronization is a logic low level, no arc detection is performed, that is, no current and voltage signals are received, and no sampling and judgment operations are performed. In this way, the RF generating device of the present application can also accurately judge the arc occurrence event in the cavity when the pulse power is output.

[0059] In other embodiments, the arc detection device 50 is configured to receive a current signal and a voltage signal after the plasma excited in the chamber by the pulsed RF power signal reaches a stable state.

[0060] The above-mentioned RF generator has an RF power supply and a set of sensors for detecting current and voltage. The RF generator of the present application can also be expanded to have multiple RF power supplies and multiple sets of sensors to perform arc detection on multiple loads in the same cavity or loads in multiple cavities.

[0061] Specifically, in some embodiments, the RF power supply described above is a first RF power supply, the current sensor is a first current sensor, and the voltage sensor is a first voltage sensor. The RF generating device further includes a second RF power supply, a second current sensor, and a second voltage sensor. The second RF power supply is connected to another load in the plasma chamber via the second voltage sensor and the second current sensor to output a second RF power signal to the load. The second current sensor detects the current at the load to generate a second current signal; the second voltage sensor detects the voltage at the load to generate a second voltage signal. The arc detection device generates a second arc generation signal based on the second current signal and the second voltage signal, and feeds the second arc generation signal to the second RF power supply so that the second RF power supply pauses outputting the second RF power signal to the plasma chamber. In this embodiment, the first RF power supply outputs the first RF power signal to the upper electrode in the plasma chamber, and the second RF power supply outputs the second RF power signal to the lower electrode in the plasma chamber. In other embodiments, the first RF power supply outputs the first RF power signal to the coil in the plasma chamber, and the second RF power supply outputs the second RF power signal to the lower electrode in the plasma chamber.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Under the concept of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present application as described above, which are not provided in detail for the sake of simplicity. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A radio frequency generating device, characterized in that: include: A radio frequency power supply configured to output a radio frequency power signal to a load in the plasma chamber; A current sensor is arranged between the RF power supply and the plasma chamber, and is used to detect the current of the load in the chamber and generate a current signal; A voltage sensor is arranged between the RF power supply and the plasma chamber, and is used to detect the voltage of the load in the chamber and generate a voltage signal; as well as The arc detection device is configured to receive the current signal and the voltage signal, and generate an arc occurrence signal indicating that an arc occurs in the cavity when the current signal value is outside the current threshold range and the voltage signal value is outside the voltage threshold range.

2. The radio frequency generating device according to claim 1, characterized in that: The arc detection device is configured to generate an arc occurrence signal indicating that an arc has occurred in the cavity when the current signal value is higher than the current upper limit threshold and the voltage signal value is lower than the voltage lower limit threshold.

3. The radio frequency generating device according to claim 1, characterized in that: The arc detection device comprises a current sampling module, wherein the current sampling module is configured to sample the current signal to generate a fast sampling current signal and a slow sampling current signal; The current threshold range is between the current upper threshold and the current lower threshold, wherein the current upper threshold is the slow sampling current signal value plus the current threshold, and the current lower threshold is the slow sampling current signal value minus the current threshold; The arc detection device is further configured to determine whether the fast sampling current signal value is within the current threshold range.

4. The radio frequency generating device according to claim 1, characterized in that: The arc detection device comprises a voltage sampling module, wherein the voltage sampling module is configured to sample the voltage signal to generate a fast sampling voltage signal and a slow sampling voltage signal; The voltage threshold range is between an upper voltage threshold and a lower voltage threshold, wherein the upper voltage threshold is the value of the slow-sampling voltage signal plus the voltage threshold, and the lower voltage threshold is the value of the slow-sampling voltage signal minus the voltage threshold; The arc detection device is further configured to determine whether the fast sampling voltage signal value is within the voltage threshold range.

5. The radio frequency generating device according to claim 1, characterized in that: The arc detection device is further configured to receive a current signal generated by the current sensor and a voltage signal generated by the voltage sensor after the plasma excited by the radio frequency power signal in the cavity reaches a stable state.

6. The radio frequency generating device according to claim 1, characterized in that: The RF power supply is further configured to receive the arc occurrence signal to stop outputting the RF power signal to the plasma chamber.

7. The radio frequency generating device according to claim 1, characterized in that: Also includes a controller, The controller is configured to receive the arc occurrence signal and time the arc occurrence time based on the arc occurrence signal, and generate a control signal to control the RF power source to output the RF power signal within an additional process time, wherein the additional process time is equal to the arc occurrence time.

8. The radio frequency generating device according to claim 1, characterized in that: The RF power supply is further configured to send a pulse synchronization signal to the arc detection device; and The arc detection device is further configured to receive the current signal and the voltage signal when the pulse synchronization signal indicates that a pulse is turned on.

9. An arc detection device, used to connect with a current sensor and a voltage sensor, wherein the current sensor is arranged between the RF power supply and the plasma chamber, and is used to detect the current of the load in the chamber and generate a current signal; the voltage sensor is arranged between the RF power supply and the plasma chamber, and is used to detect the voltage of the load in the chamber and generate a voltage signal; the RF power supply is configured to output a RF power signal to the load in the plasma chamber, wherein: The arc detection device is configured to receive the current signal and the voltage signal, and to generate an arc occurrence signal indicating that an arc occurs in the cavity when the current signal value is outside a current threshold range and the voltage signal value is outside a voltage threshold range.

10. The arc detection device according to claim 9, characterized in that: The arc detection device is configured to generate an arc occurrence signal indicating that an arc has occurred in the cavity when the current signal value is higher than the current upper limit threshold and the voltage signal value is lower than the voltage lower limit threshold.

11. The arc detection device according to claim 9, characterized in that: The arc detection device comprises a current sampling module, wherein the current sampling module is configured to sample the current signal to generate a fast sampling current signal and a slow sampling current signal; The current threshold range is between the current upper threshold and the current lower threshold, wherein the current upper threshold is the slow sampling current signal value plus the current threshold, and the current lower threshold is the slow sampling current signal value minus the current threshold; The arc detection device is further configured to determine whether the fast sampling current signal value is within the current threshold range.

12. The arc detection device according to claim 9, characterized in that: The arc detection device comprises a voltage sampling module, wherein the voltage sampling module is configured to sample the voltage signal to generate a fast sampling voltage signal and a slow sampling voltage signal; The voltage threshold range is between an upper voltage threshold and a lower voltage threshold, wherein the upper voltage threshold is the value of the slow-sampling voltage signal plus the voltage threshold, and the lower voltage threshold is the value of the slow-sampling voltage signal minus the voltage threshold; The arc detection device is further configured to determine whether the fast sampling voltage signal value is within the voltage threshold range.

13. The arc detection device according to claim 9, characterized in that: The arc detection device is further configured to receive a pulse synchronization signal sent by the RF power source, and when the pulse synchronization signal indicates that a pulse is on, receive a current signal generated by the current sensor and a voltage signal generated by the voltage sensor.

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