Radio frequency power supply control method and device, radio frequency power supply and semiconductor process equipment

Abstract

The invention provides a control method and device of a radio frequency power supply, the radio frequency power supply and semiconductor process equipment, and is applied to the technical field of semiconductor process equipment, the method is applied to the radio frequency power supply which provides at least one pulse signal in each work period, and in the at least one pulse signal in each work period of the radio frequency power supply, the pulse signal is transmitted to the radio frequency power supply. Wherein one pulse signal is controlled according to a first control mode, and the first control mode is as follows: according to a forward power feedback value, a reflection power feedback value, a dissipation power feedback value and a bus voltage threshold value of a current radio frequency power supply, a bus voltage output to the radio frequency power supply is adjusted, and a bias voltage output to the radio frequency power supply is kept unchanged; compared with a protection circuit built according to electronic components in the prior art, the invention provides a software protection mechanism, the execution process is not easily influenced by factors such as environment temperature and electromagnetic interference, the protection mechanism is more reliable, and the safety of the radio frequency power supply in the operation process can be ensured.

Description

Technical Field

[0001] The present application relates to the technical field of radio frequency power supply, and in particular to a control method and device of a radio frequency power supply, a radio frequency power supply and semiconductor process equipment. Background Art

[0002] At present, RF power supply is one of the core components of semiconductor process equipment, mainly used to provide high-frequency plasma excitation source for semiconductor process equipment. With the continuous improvement of semiconductor process and the continuous upgrading of semiconductor process equipment, the requirements for the safety of RF power supply during operation are getting higher and higher.

[0003] In order to improve the safety of the RF power supply during operation, the prior art sets a protection circuit in the RF power supply. The protection circuit collects the forward power and the reflected power during the operation of the RF power supply. When the forward power is greater than a preset forward power setting value, a forward power control amount is provided to control the forward power within a preset range. When the reflected power is greater than a preset reflected power threshold, a reflected power control amount is provided to control the reflected power within a preset range.

[0004] The inventors have discovered that the protection mechanism of the RF power supply in the prior art is implemented based on analog circuits. The electronic components in the protection circuit are often affected by factors such as ambient temperature and electromagnetic interference, which leads to unstable performance of the protection circuit, malfunction of the protection mechanism, or even failure of the protection mechanism. This makes it difficult to effectively protect the safety requirements during the operation of the RF power supply. Summary of the invention

[0005] In view of this, the present application is committed to providing a control method and device of an RF power supply, an RF power supply and semiconductor process equipment to solve the problem in the prior art that the protection circuit is difficult to effectively protect the operating safety of the RF power supply.

[0006] In a first aspect, the present application provides a control method for a radio frequency power supply, wherein the radio frequency power supply provides at least one pulse signal in each working cycle, and the control method comprises:

[0007] In each of the working cycles, one of the at least one pulse signal is controlled according to a first control method;

[0008] The first control method: adjusts the bus voltage output to the RF power supply according to the current forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the RF power supply, and maintains the bias voltage output to the RF power supply unchanged.

[0009] In an optional embodiment, the radio frequency power supply provides at least two pulse signals in each of the working cycles;

[0010] Among the at least two pulse signals, the pulse signal with the largest forward power setting value is controlled according to the first control mode, and the remaining pulse signals except the pulse signal with the largest forward power setting value are controlled according to the second control mode;

[0011] The second control mode is to adjust the bias voltage output to the RF power supply according to the current forward power feedback value and reflected power feedback value of the RF power supply, and maintain the bus voltage of the RF power supply unchanged.

[0012] In an optional implementation, adjusting the bus voltage output to the RF power supply according to the forward power feedback value, the reflected power feedback value, the dissipated power feedback value and the bus voltage threshold of the current RF power supply includes:

[0013] Obtaining a forward power setting value, a reflected power threshold, a dissipated power threshold, a forward power feedback value, a reflected power feedback value, a dissipated power feedback value, and a bus voltage threshold of the current RF power supply;

[0014] Determining a forward power control amount according to a forward power deviation between the forward power setting value and the forward power feedback value;

[0015] Determining a reflected power control amount according to a reflected power deviation between the reflected power threshold and the reflected power feedback value;

[0016] Determining a dissipated power control amount according to a dissipated power deviation between the dissipated power threshold and the dissipated power feedback value;

[0017] Determine a first target control amount according to the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold;

[0018] The bus voltage output to the RF power supply is adjusted according to the first target control amount.

[0019] In an optional implementation manner, determining the first target control amount according to the forward power control amount, the reflected power control amount, the dissipated power control amount, and the bus voltage threshold includes:

[0020] The smallest value among the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold is determined as the first target control amount.

[0021] In an optional implementation manner, obtaining the bus voltage threshold includes:

[0022] Determine a current proportionality coefficient according to a ratio of the reflected power feedback value to the forward power feedback value;

[0023] The bus voltage threshold is determined according to the current proportionality coefficient and a predetermined corresponding relationship between the bus voltage threshold and the proportionality coefficient.

[0024] In an optional implementation manner, the predetermined corresponding relationship between the bus voltage threshold and the proportionality coefficient includes:

[0025] When the proportionality coefficient is less than or equal to the first threshold value, the bus voltage threshold corresponding to the proportionality coefficient is the first voltage value;

[0026] When the proportionality coefficient is greater than or equal to the second threshold, the bus voltage threshold corresponding to the proportionality coefficient is a second voltage value, and the second threshold is greater than the first threshold;

[0027] When the proportionality coefficient is greater than the first threshold and less than the second threshold, the proportionality coefficient is inversely proportional to the bus voltage threshold.

[0028] In an optional implementation, adjusting the bias voltage of the RF power supply according to the forward power and the reflected power of the RF power supply includes:

[0029] Obtaining a forward power setting value, a reflected power threshold, a forward power feedback value, and a reflected power feedback value of the RF power supply;

[0030] Determining a forward power control amount according to a forward power deviation between the forward power setting value and the forward power feedback value;

[0031] Determining a reflected power control amount according to a reflected power deviation between the reflected power threshold and the reflected power feedback value;

[0032] Determine the minimum control amount among the forward power control amount and the reflected power control amount as the second target control amount;

[0033] The bias voltage of the RF power supply is adjusted according to the second target control amount.

[0034] In a second aspect, the present application provides a control device for a radio frequency power supply, wherein the radio frequency power supply provides at least one pulse signal in each working cycle, and the control device comprises:

[0035] A main control unit, configured to control, in each of the working cycles, one of the at least one pulse signal according to a first control mode;

[0036] The first control method: adjusts the bus voltage output to the RF power supply according to the current forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the RF power supply, and maintains the bias voltage output to the RF power supply unchanged.

[0037] In an optional embodiment, the radio frequency power supply provides at least two pulse signals in each of the working cycles;

[0038] The main control unit is configured to control, among the at least two pulse signals, the pulse signal with the largest forward power setting value according to the first control mode, and control the remaining pulse signals except the pulse signal with the largest forward power setting value according to the second control mode;

[0039] The second control mode is to adjust the bias voltage output to the RF power supply according to the current forward power feedback value and reflected power feedback value of the RF power supply, and maintain the bus voltage of the RF power supply unchanged.

[0040] In an optional implementation, the main control unit includes: a forward power control amount calculation unit, a reflected power control amount calculation unit, a reflected power control amount calculation unit, a dissipated power control amount calculation unit, a comparison unit and a control unit, wherein:

[0041] The forward power control amount calculation unit is used to obtain the current forward power setting value and the forward power feedback value of the RF power supply, and determine the forward power control amount according to the forward power deviation between the forward power setting value and the forward power feedback value;

[0042] The reflected power control amount calculation unit is used to obtain the reflected power threshold and reflected power feedback value of the current RF power supply, and determine the reflected power control amount according to the reflected power deviation between the reflected power threshold and the reflected power feedback value;

[0043] The dissipated power control amount calculation unit is used to obtain the current dissipated power threshold and dissipated power feedback value of the RF power supply, and determine the dissipated power control amount according to the dissipated power deviation between the dissipated power threshold and the dissipated power feedback value;

[0044] The comparison unit is used to determine a first target control amount according to the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold;

[0045] The control unit is used to adjust the bus voltage output to the RF power supply according to the first target control amount.

[0046] In an optional implementation manner, the comparison unit is further configured to determine the minimum control amount among the forward power control amount and the reflected power control amount as the second target control amount;

[0047] The control unit is further configured to adjust the bias voltage of the RF power supply according to the second target control amount.

[0048] In a third aspect, the present application provides a radio frequency power supply, including: a main controller, a power amplifier circuit and a sampling circuit, wherein:

[0049] The sampling circuit is connected to the power amplifier circuit;

[0050] The main controller is connected to the power amplifier circuit and the sampling circuit respectively;

[0051] The main controller is used to execute the control method of the radio frequency power supply as described in any one of the first aspects of the present application.

[0052] In a fourth aspect, the present application provides a semiconductor process equipment, comprising: a process chamber and at least one RF power supply as described in the third aspect of the present application, wherein:

[0053] The radio frequency power supply is used to provide radio frequency power to the process chamber to excite the process gas in the process chamber to generate plasma.

[0054] According to the above content, the control method provided in the present application is applied to an RF power supply that provides at least one pulse signal in each working cycle. In the present method, among the at least one pulse signal in each working cycle of the RF power supply, one pulse signal is controlled according to a first control method. The first control method is: adjusting the bus voltage output to the RF power supply according to the forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the current RF power supply, and maintaining the bias voltage output to the RF power supply unchanged. Compared with the protection circuit built according to electronic components in the prior art, the control method of the RF power supply provided in the present application provides a software protection mechanism for the RF power supply. The execution process is not easily affected by factors such as ambient temperature and electromagnetic interference. The protection mechanism is more reliable and can effectively ensure the safety of the RF power supply during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0056] Figure 1a-1b It is a waveform diagram of the RF power supply output pulse signal.

[0057] Figure 2 It is a flow chart of a method for controlling a radio frequency power supply provided by an embodiment of the present invention.

[0058] Figure 3 It is a voltage schematic diagram of a power switch tube provided in an embodiment of the present invention.

[0059] Figure 4 It is a flow chart of a bus current calculation method provided by an embodiment of the present invention.

[0060] Figure 5 It is a schematic diagram of the mapping relationship between the proportionality coefficient and the bus voltage threshold provided in an embodiment of the present invention.

[0061] Figure 6 It is a variation curve diagram of the forward power control amount, the dissipated power control amount and the reflected power control amount provided by the embodiment of the present invention.

[0062] Figure 7 It is a flow chart of a control quantity calculation method provided by an embodiment of the present invention.

[0063] Figure 8 It is a flow chart of another control amount calculation method provided by an embodiment of the present invention.

[0064] Fig. 9 It is a structural block diagram of a control device for a radio frequency power supply provided by an embodiment of the present invention.

[0065] Fig.10 It is a structural block diagram of another control device of a radio frequency power supply provided in an embodiment of the present invention.

[0066] Fig.11 It is a waveform diagram of another pulse signal output by the RF power supply.

[0067] Fig.12 It is a structural block diagram of a radio frequency power supply provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. According to the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0069] As mentioned above, in order to improve the safety of the RF power supply during operation, the prior art sets a protection circuit in the RF power supply. When the forward power is greater than the preset forward power setting value, a forward power control amount is provided to control the forward power within a preset range, and when the reflected power is greater than the preset reflected power threshold, a reflected power control amount is provided to control the reflected power within a preset range. The prior art implements the protection mechanism of the RF power supply based on analog circuits. The electronic components in the protection circuit are often affected by factors such as ambient temperature and electromagnetic interference, resulting in unstable performance of the protection circuit, malfunction of the protection mechanism, or even failure of the protection mechanism, making it difficult to effectively protect the safety requirements during the operation of the RF power supply.

[0070] To solve the above problems, the present application provides a control method for an RF power supply. Compared with the protection circuit built by electronic components in the prior art, the present application provides a software protection mechanism for the RF power supply. The execution process is not easily affected by factors such as ambient temperature and electromagnetic interference. The protection mechanism is more reliable and can effectively ensure the safety of the RF power supply during operation.

[0071] The control method of the RF power supply provided in the present application is applied to an electronic device, which can be a main controller set by the RF power supply itself, or a controller independent of the RF power supply, such as a host computer in a semiconductor process equipment. Of course, in some cases, it can also be a server set at a remote end. The control method of the RF power supply provided in the present application provides a protection mechanism for the RF power supply during operation. The RF power supply can provide at least one pulse signal in each working cycle. For example, when the RF power supply provides a pulse signal, the output pulse signal can refer to Figure 1a As shown, that is, in the same operation cycle, the RF power supply provides the same type of pulse signal; for example, when the RF power supply provides two or more pulse signals, the output pulse signal can be seen in Figure 1b As shown ( Figure 1b Taking providing four types of pulse signals as an example), that is, within the same operation cycle, the RF power supply outputs pulse signal 1, pulse signal 2, pulse signal 3 and pulse signal 4 in sequence according to the preset output rules of the pulse signal.

[0072] Based on the above, see Figure 2 As shown, the control method of the radio frequency power supply provided in the present application includes the following steps.

[0073] S100. Among at least one pulse signal in each working cycle, one pulse signal is controlled according to a first control method.

[0074] In practical applications, the RF power supply outputs a pulse signal in any working cycle and can be divided into two optional implementations. In one optional implementation, the RF power supply outputs a pulse signal in any working cycle. In this case, the method controls the pulse signal according to the first control mode. Figure 1a As an example, if the RF power supply only provides Figure 1a A pulse signal is shown, that is, the pulse signal is controlled according to the first control mode.

[0075] In another optional embodiment, the RF power supply outputs two or more pulse signals in any working cycle. For example, the RF power supply can provide Figure 1b The various pulse signals shown are pulse signal 1, pulse signal 2, pulse signal 3 and pulse signal 4.

[0076] It is understandable that, in practical applications, the RF power supply outputs a pulse signal based on the forward power setting value, wherein the forward power setting value is mainly used to configure the RF power provided during the operation of the RF power supply, and is also the RF power required by the user. In practical applications, the forward power setting value can be provided by a host computer or a slave computer connected to the RF power supply for controlling the operation of the RF power supply. This application does not limit the specific configuration method of the forward power setting value and the reflected power threshold and the dissipated power threshold described in the subsequent content. The specific implementation can be referred to the relevant technology, which will not be described in detail here. More importantly, each pulse signal corresponds to a forward power setting value, that is, there is a one-to-one correspondence between the pulse signal and the forward power setting value.

[0077] Based on the above content, among the at least two pulse signals provided by the RF power supply, the present application controls the pulse signal with the largest forward power setting value according to the first control method, and controls the remaining pulse signals except the pulse signal with the largest forward power setting value according to the second control method. Figure 1b As shown in the figure, among the four pulse signals provided by the RF power supply, the forward power setting value corresponding to pulse signal 4 is the largest, that is, the output of pulse signal 4 is controlled according to the first control method, and the remaining pulse signals are controlled according to the second control method.

[0078] Furthermore, the first control method mentioned in the above content is specifically: adjusting the bus voltage output to the RF power supply according to the forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the current RF power supply, and maintaining the bias voltage output to the RF power supply unchanged. The second control method is specifically: adjusting the bias voltage output to the RF power supply according to the forward power feedback value and reflected power feedback value of the current RF power supply, and maintaining the bus voltage of the RF power supply unchanged.

[0079] It should be noted that in the present application, a power amplifier circuit composed of a power switch tube is provided in the RF power supply. Figure 3 As shown, the power switch tube Q 0 The voltage between the source (S) and the drain (D) is the bus voltage V mentioned in this application. bus , accordingly, the power switch tube Q 0 The voltage between the gate (G) and the source is the bias voltage V mentioned in this application. bias .

[0080] It is understandable that, for an RF power supply that provides multiple pulse signals in the same operating cycle, accurately identifying the current output pulse signal is a basic prerequisite for ensuring the reliability of the protection mechanism.

[0081] As mentioned above, the RF power supply will output each pulse signal according to the preset output rule, wherein the preset output rule includes the output order of each pulse signal and the preset duration of each pulse signal (it can also be the preset number of pulses included in each pulse signal). Figure 1b For example, in any operation cycle, the RF power supply first outputs pulse signal 1. Based on this, the duration of the RF power supply outputting pulse signal 1 is counted. When the counted duration reaches the preset duration of pulse signal 1, it is confirmed that the output of pulse signal 1 is completed. During the period from when the RF power supply starts to output pulse signal 1 to when the counted duration reaches the duration corresponding to the preset duration, pulse signal 1 is the pulse signal currently provided by the RF power supply. After the output of pulse signal 1 is completed, the output of pulse signal 2 is monitored according to the aforementioned method. During the process of outputting pulse signal 2, pulse signal 2 is the pulse signal currently provided by the RF power supply. Of course, the above process can also be implemented according to the preset number of pulses of each pulse signal, that is, in any operation cycle, the RF power supply first outputs pulse signal 1. Based on this, the number of pulses of the RF power supply outputting pulse signal 1 is counted. When the statistical value of the number of pulses reaches the preset number of pulses of pulse signal 1, it is confirmed that the output of pulse signal 1 is completed. During the period from when the RF power supply starts to output pulse signal 1 to when the statistical value of the number of pulses reaches the preset number of pulses, pulse signal 1 is the pulse signal currently provided by the RF power supply. And so on, which will not be repeated here.

[0082] For a scenario where the RF power source outputs a pulse signal in any operating cycle, the above identification process can be omitted.

[0083] To sum up, compared with the protection circuit built based on electronic components in the prior art, the control method of the RF power supply provided in the present application provides a software protection mechanism for the RF power supply. The execution process is not easily affected by factors such as ambient temperature and electromagnetic interference. The protection mechanism is more reliable and can effectively ensure the safety of the RF power supply during operation.

[0084] The bus voltage threshold can be used to limit the DC voltage output by the DC power supply in the RF power supply, ensuring that the DC voltage provided by the DC power supply does not exceed the maximum tolerance voltage of the switching tube in the power amplifier circuit, thereby effectively ensuring the safe operation of the power amplifier circuit and improving the overall operating safety of the RF power supply.

[0085] The following describes a specific implementation method of the first control method provided in the present application. The specific process of adjusting the bus voltage output to the RF power supply according to the forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the current RF power supply in the first control method may include the following steps.

[0086] First, the forward power setting value, the reflected power threshold, the dissipated power threshold, the forward power feedback value, the reflected power feedback value and the dissipated power feedback value corresponding to the pulse signal output by the current RF power supply are obtained.

[0087] Specifically, the forward power setting value is mainly used to configure the RF power provided during the process of the RF power supply outputting a pulse signal, and is also the RF power required by the user. As mentioned above, in actual applications, the forward power setting values ​​corresponding to different pulse signals output by the RF power supply are different. The reflected power threshold corresponds to the maximum reflected power allowed by the RF power supply. When the reflected power is greater than the reflected power threshold, it is easy for the RF power supply to cause thermal damage to the matcher and RF cable of the semiconductor process equipment due to excessive reflected power. Correspondingly, the dissipated power threshold corresponds to the maximum dissipated power allowed by the RF power supply. When the dissipated power is greater than the reflected power threshold, it is easy for the RF power supply to cause thermal breakdown due to excessive dissipated power. In actual applications, the reflected power threshold and the dissipated power threshold need to be set in combination with the performance parameters of the RF power supply, the specific conditions of the power supply load, and the control requirements. This application does not limit the specific values ​​of the reflected power threshold and the dissipated power threshold.

[0088] Similar to the forward power setting value, the reflected power threshold and dissipated power threshold corresponding to different pulse signals output by the RF power supply are also different. In practical applications, it is necessary to obtain the forward power setting value, reflected power threshold and dissipated power threshold corresponding to the pulse signal currently output by the RF power supply. Furthermore, the forward power setting value, reflected power threshold and dissipated power threshold can all be provided by a host computer or a slave computer connected to the RF power supply for controlling the operation process of the RF power supply. This application does not limit the specific configuration method of the forward power setting value, reflected power threshold and dissipated power threshold. The specific implementation can be referred to the relevant technology, which will not be described in detail here.

[0089] As an optional implementation, a sampling circuit is configured in the RF power supply, and the input end of the sampling circuit is connected to the output end of the power amplifier circuit in the RF power supply. The sampling circuit can collect the forward power and reflected power during the operation of the RF power supply, and after the obtained forward power and reflected power are subjected to signal processing operations such as frequency calibration, they are output as forward power feedback values ​​and reflected power feedback values. The electronic device that executes this method is connected to the output end of the sampling circuit to obtain the forward power feedback value and reflected power feedback value of the corresponding pulse signal.

[0090] In an optional implementation, the duration of the RF power supply output pulse signal can be counted. When the counted duration does not reach the preset duration corresponding to the pulse signal, multiple forward power feedback values ​​and reflected power feedback values ​​provided by the sampling circuit are collected according to a preset sampling period, and then the average value of each forward power feedback value is calculated, and the obtained forward power average value is used as the final forward power feedback value. Correspondingly, the average value of each reflected power feedback value is calculated, and the obtained reflected power average value is used as the final reflected power feedback value.

[0091] The dissipated power feedback value needs to be obtained through calculation. As an optional calculation method, first obtain the current bus voltage of the DC power supply in the RF power supply and the target bus current used to calculate the dissipated power, calculate the product of the current bus voltage and the target bus current, and obtain the first power value. According to the first power value, the forward power feedback value and the reflected power feedback value, determine the dissipated power feedback value. Specifically, the sum of the difference between the first power value and the forward power feedback value and the reflected power feedback value is the dissipated power feedback value.

[0092] In the case where the RF power supply provides multiple pulse signals, the RF power corresponding to the output of different pulse signals is different, and the generated dissipated power will naturally be different. Based on this, as an optional implementation, this embodiment provides a method for determining the target bus current, which can be specifically adopted as follows: Figure 4 The process steps shown are implemented.

[0093] S1001. Obtain the current bus current of the DC power supply and the target bus current of the previous cycle.

[0094] It should be noted that the previous cycle mentioned in this embodiment refers to the previous protection cycle of executing this method, and the current bus current refers to the bus current of the DC power supply during the process of the DC power supply outputting the current pulse signal.

[0095] S1002, determine whether the current bus current is greater than the target bus current of the previous cycle, if so, execute S1003, if not, execute S1004.

[0096] S1003. Determine that the current bus current is the target bus current of the current cycle.

[0097] If the current bus current is greater than the target bus current of the previous cycle, the current bus current is determined to be the target bus current of the current cycle.

[0098] S1004. Determine the target bus current of the previous cycle as the target bus current of the current cycle.

[0099] If the current bus current is less than or equal to the target bus current of the previous cycle, the target bus current of the previous cycle is used as the target bus current of the current cycle.

[0100] It can be seen from the above process that the target bus current determination method provided in the above embodiment is to use the maximum bus current in all previous protection cycles as the target bus current. With such a setting, the maximum dissipated power feedback value can be calculated. With such a setting, the effective triggering of the dissipated power protection mechanism can be ensured, which corresponds to a larger safety margin for the RF power supply.

[0101] In another optional implementation, the average value of the bus currents of previous protection cycles can be used as the target bus current of the current cycle, which is also feasible. Of course, other methods can also be used to determine the target bus current, which also falls within the scope of protection of the present application without exceeding the concept of the present application.

[0102] According to the above content, the forward power control amount can be determined according to the forward power deviation between the forward power setting value and the forward power feedback value, the reflected power control amount can be determined according to the reflected power deviation between the reflected power threshold and the reflected power feedback value, and the dissipated power control amount can be determined according to the dissipated power deviation between the dissipated power threshold and the dissipated power feedback value. The specific calculation process of the forward power control amount, the reflected power control amount and the dissipated power control amount will be expanded in the subsequent content and will not be described in detail here.

[0103] It should be noted that the forward power control amount, reflected power control amount and dissipated power control amount mentioned in this embodiment are essentially pure numerical values ​​without any physical units. Their functions will vary depending on their specific application scenarios. In this application, each control amount can be used to adjust the operation of the RF power supply. As for the specific adjustment process, it will be expanded in subsequent content and will not be described in detail here.

[0104] Furthermore, the control method provided in the present application also needs to further obtain a bus voltage threshold.

[0105] In a possible implementation, the bus voltage threshold can be determined based on a change in the ratio between the aforementioned reflected power feedback value and the forward power feedback value, that is, the current proportional coefficient is first determined based on the ratio of the reflected power feedback value to the forward power feedback value, and then the bus voltage threshold is determined based on the obtained current proportional coefficient and a predetermined correspondence between the bus voltage threshold and the proportional coefficient.

[0106] Specific, combined Figure 5 As shown, as an optional implementation, when the proportional coefficient is less than or equal to the first threshold value VSWR1, the bus voltage threshold corresponding to the obtained proportional coefficient is the first voltage value (corresponding to curve L1), when the obtained proportional coefficient is greater than or equal to the second threshold value VSWR2, the bus voltage threshold corresponding to the obtained proportional coefficient is the second voltage value (corresponding to curve L3), when the obtained proportional coefficient is greater than the first threshold value VSWR1 and less than the second threshold value VSWR2, the obtained proportional coefficient is inversely proportional to the bus voltage threshold (corresponding to curve L2), wherein the second threshold value is greater than the first threshold value.

[0107] In one possible implementation, Figure 5 The corresponding relationship shown can be determined as follows.

[0108] First, multiple sample coefficients are selected between a first threshold and a second threshold, and for each sample coefficient, a forward power feedback value, a reflected power feedback value, and a bus voltage threshold acting on the RF power supply when the RF power supply is in the sample coefficient are obtained.

[0109] For each sample coefficient, the power ratio corresponding to each sample coefficient can be calculated according to formula (1).

[0110]

[0111] Among them, K X represents the sample coefficient;

[0112] R x K X The corresponding reflected power feedback value;

[0113] F x K X The corresponding forward power feedback value.

[0114] Furthermore, according to the above-obtained data, the corresponding relationship between each sample coefficient and the bus voltage threshold of the RF power supply is fitted, and the corresponding relationship between the bus voltage threshold of the RF power supply and the sample coefficient can be obtained, which can be shown as formula (2):

[0115] AgcOut=A 1 *(A 2 -KX ×A 2 ) (2)

[0116] Where, AgcOut represents the bus voltage threshold, A 2 and A 1 All are fitting coefficients.

[0117] It can be understood that the formula (2) is used to record the corresponding relationship between different proportional coefficients and bus voltage thresholds.

[0118] Among them, the first threshold VSWR1 represents the ratio between the reflected power feedback value and the forward power feedback value when the power amplifier tube is damaged during the test, and the second threshold VSWR2 represents the ratio between the reflected power feedback value and the forward power feedback value when the reflection protection is reached.

[0119] It should be noted that the above-mentioned bus voltage threshold can be understood as being determined according to a piecewise function. In practical applications, it can also be determined using a quadratic function or other forms. They are not listed one by one here. Unless it exceeds the core idea of ​​this application, it also falls within the scope of protection of this application.

[0120] After the above steps, the forward power control amount, reflected power control amount, dissipated power control amount and bus voltage threshold of the current RF power supply have been obtained. Based on this, the present application further determines the above-mentioned first target control amount according to the obtained forward power control amount, reflected power control amount, dissipated power control amount and bus voltage threshold.

[0121] In an optional implementation, the present application determines the smallest value among the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold as the first target control amount, that is, the control method provided in this embodiment provides four-dimensional protection mechanisms, namely, the forward power protection mechanism, the reflected power protection mechanism, the dissipated power protection mechanism and the overvoltage protection mechanism. Among them, the forward power protection mechanism, the reflected power protection mechanism and the dissipated power protection mechanism have a mutually restrictive control relationship.

[0122] Combination Figure 6 As shown, in actual applications, the forward power protection mechanism, the reflected power protection mechanism and the dissipated power protection mechanism should meet the following control rules: when the reflected power and the dissipated power are normal, only the forward power mechanism is effective, and the RF power supply is controlled to output the RF power according to the forward power setting value.

[0123] To achieve the above purpose, the following conditions must be met: when the reflected power feedback value is less than the reflected power threshold, the reflected power control amount is greater than the forward power control amount; when the reflected power feedback value is greater than or equal to the reflected power threshold, the reflected power control amount is less than the forward power control amount.

[0124] Correspondingly, when the dissipated power feedback value is less than the dissipated power threshold, the dissipated power control amount is greater than the forward power control amount; when the dissipated power feedback value is greater than or equal to the dissipated power threshold, the dissipated power control amount is less than the forward power control amount.

[0125] According to the above content, the smallest control amount among the three should be used as the control amount for further comparison with the bus voltage threshold. Therefore, if the reflected power feedback value is less than the reflected power threshold and the dissipated power feedback value is less than the dissipated power threshold, the reflected power control amount and the reflected power control amount are both greater than the forward power control amount, which can ensure that the forward power control amount is used as the control amount for further comparison with the bus voltage threshold. Correspondingly, in the protection triggering scenario, the reflected power control amount or the dissipated power control amount is output to reduce the RF power at the RF power supply end and return to normal as soon as possible. Taking the reflected power protection mechanism as an example, when the reflected power feedback value is greater than the reflected power threshold, the reflected power control amount is less than the dissipated power control amount and the forward power control amount, ensuring that the reflected power control amount can be output as the control amount compared with the bus voltage threshold, thereby achieving reflected power abnormality protection when the voltage is normal.

[0126] After determining the first target control amount, the bus voltage output to the RF power supply is further adjusted according to the first target control amount, and the bias voltage of the RF power supply is maintained unchanged.

[0127] In an optional implementation, the bus voltage regulation process may be implemented with reference to the following formula (3).

[0128] Out=(A 3 ×,V bus ) 2 / 65535 (3)

[0129] Among them, A 3 Indicates bus voltage V bus The conversion coefficient between A and the first target control quantity Out can be obtained by fitting the specific circuit parameters and test data in practical applications. 3 The specific value of is not limited. 65535 is a constant in the conversion process, which can be regarded as the full-scale value corresponding to the maximum DC voltage that the DC power supply can output. Of course, the aforementioned A 3 The specific value of is also related to the full-scale value, which can be determined in combination with relevant technologies and will not be described in detail here.

[0130] Formula (3) defines the relationship between Out and V busThe mapping relationship between them, when the first target control amount is determined through the above steps, the corresponding bus voltage can be calculated according to formula (3), and the bus voltage of the RF power supply can be further adjusted according to the obtained result. As mentioned above, in this scenario, it is inconvenient to maintain the bias voltage of the DC power supply.

[0131] In practical applications, considering that the execution cycle of the bus voltage control method is longer than that of the bias voltage control method, and the bus voltage control method has a higher linearity in the regulation process under larger RF power than the bias voltage control method, therefore, when the RF power supply provides different types of pulse signals, the first control method is preferentially used when outputting a pulse signal with the largest forward power setting value, and the second control method is used when outputting other pulse signals.

[0132] The specific implementation method of the second control method provided in the present application is introduced below. The specific process of adjusting the bias voltage of the RF power supply according to the forward power and reflected power of the RF power supply in the second control method may include the following steps.

[0133] First, the forward power setting value, the reflected power threshold, the forward power feedback value and the reflected power feedback value of the RF power supply are obtained, and the forward power control amount is determined according to the forward power deviation between the forward power setting value and the forward power feedback value, and the reflected power control amount is determined according to the reflected power deviation between the reflected power threshold and the reflected power feedback value. As for the specific implementation process of this step, it can be implemented with reference to the relevant contents of the aforementioned embodiment, which will not be repeated here.

[0134] Furthermore, the minimum control amount of the forward power control amount and the reflected power control amount is determined as the second target control amount. It is understandable that when the RF power supply provides at least two pulse signals, the RF power supply will frequently switch the output pulse signal. Since the dissipated power feedback value needs to be calculated in combination with the current bus voltage, the target bus current, the forward power feedback value, and the reflected power feedback value, and the sampling period of the DC voltage and DC current is relatively long, the determination of the dissipated power takes a long time. If the dissipated power control amount is calculated once for each output pulse signal, it will take a lot of time and may even cause system disorder. Moreover, if the dissipated power of the pulse signal with the largest output forward power setting value does not cause abnormality in the RF power supply, other pulse signals will most likely not cause abnormality in the RF power supply.

[0135] After determining the second target control amount, the bias voltage of the RF power supply can be adjusted according to the second target control amount. In practical applications, the mapping relationship between the bias voltage and the second target control amount is similar to formula (3). After determining the second target control amount, the bias voltage of the RF power supply can be adjusted in a similar manner. As for the specific adjustment process, it can be implemented with reference to relevant technologies and will not be described in detail here.

[0136] In an optional implementation, the following method may be used to determine the forward power control amount, the reflected power control amount, and the dissipated power control amount.

[0137] The control methods of the RF power supply provided in the aforementioned embodiments all involve the process of determining the forward power control amount, the reflected power control amount and the dissipated power control amount. These three control amounts can be calculated based on the core idea of ​​the PID algorithm. The following introduces several methods provided in this application for calculating each control amount based on the core idea of ​​the PID algorithm.

[0138] See also Figure 7 As shown, the control amount calculation method provided in this embodiment includes the following steps.

[0139] S300: Obtain a control amount increment corresponding to the target parameter according to a deviation between a threshold value of the target parameter and a feedback value.

[0140] As mentioned above, the three parameters of forward power control amount, reflected power control amount and dissipated power control amount can be obtained using the same calculation algorithm. Based on this, the target parameter mentioned in this embodiment can be any one of the forward power, reflected power and dissipated power. Correspondingly, the threshold of the forward power is the forward power threshold mentioned in the above embodiment, the feedback value of the forward power is the forward power feedback value, the threshold of the reflected power is the reflected power threshold mentioned in the above embodiment, the feedback value of the reflected power is the reflected power feedback value, the threshold of the dissipated power is the dissipated power threshold mentioned in the above embodiment, and the feedback value of the dissipated power is the dissipated power feedback value.

[0141] According to the above content, according to the deviation between the threshold value of the target parameter and the feedback value, the control amount increment corresponding to the corresponding parameter is obtained. Taking the forward power as an example, the deviation between the forward power threshold value and the forward power feedback value is calculated to obtain the forward power deviation, and then the forward power deviation can be used as input to determine the control amount increment corresponding to the forward power. Among them, the specific implementation of determining the control amount increment according to the forward power deviation can be implemented by referring to the relevant content of the PID algorithm, which will not be described in detail here.

[0142] S310, determining the sum of the control amount increment and the target control amount of the previous cycle as the current control amount of the target parameter.

[0143] The sum of the control amount increment obtained in S300 and the target control amount of the previous cycle is calculated as the control amount of the target parameter in the current cycle. Still taking the forward power as the target parameter as an example, after obtaining the control amount increment of the forward power in the current cycle, the sum of the control amount increment of the current cycle and the minimum control amount among the multiple control amounts determined in the previous cycle, that is, the target control amount, is calculated, and the result is used as the control amount of the forward power in the current cycle, that is, the forward power control amount.

[0144] According to the above content, it can be seen that when the forward power, reflected power and dissipated power are all calculated according to the above algorithm, if the reflected power and dissipated power do not exceed their respective corresponding thresholds, the control amount of each parameter will eventually reach the following value: Figure 8 The effect shown, wherein curve S1 represents the reflected power control amount, S2 represents the dissipated power control amount, and S3 represents the forward power control amount. Specifically, according to the basic principle of the PID algorithm, when the reflected power and the dissipated power have not reached the corresponding power threshold, the reflected power control amount and the dissipated power control amount will always be in an accumulated state, and the corresponding control amount will continue to increase. However, since the PID algorithm needs to set the maximum calculated value output by the PID algorithm during the application process to avoid the unlimited increase of the calculation result of the PID algorithm, the target control amount finally output to the DC power supply will not be greater than the maximum calculated value. Therefore, it can also be understood that the reflected power control amount and the dissipated power control amount will be in a stable state after reaching the maximum calculated value and will no longer rise. After a certain period of closed-loop control, the forward power control amount gradually stabilizes near the forward power setting value. At this time, the forward power control amount will also be synchronously stable, so that the output of the entire RF power supply enters a stable state. In this case, the forward power control amount will not be further accumulated, so it will be much smaller than the dissipated power control amount and the reflected power control amount, thereby ensuring that the forward power control amount can be used as the target control amount to control the output of the DC power supply. Figure 8 It can also be seen that the forward power setting value is less than the aforementioned maximum calculated value.

[0145] It can be seen that the control amount calculation method provided in this embodiment can meet the relevant rules described in the above-mentioned embodiments, namely: when the reflected power feedback value is less than the reflected power threshold, the reflected power control amount is greater than the forward power control amount, and correspondingly, when the dissipated power feedback value is less than the dissipated power threshold, the dissipated power control amount is greater than the forward power control amount.

[0146] According to the basic principle of PID algorithm, when the reflected power feedback value is greater than or equal to the reflected power threshold, the reflected power control amount will become smaller and then smaller than the forward power control amount. Correspondingly, when the dissipated power feedback value is greater than or equal to the dissipated power threshold, the dissipated power control amount will also be smaller than the forward power control amount.

[0147] According to the control amount calculation method provided in this embodiment, the control amount of each parameter in the current cycle is calculated according to the target control amounts of the forward power control amount, the reflected power control amount and the dissipated power control amount in the previous cycle. In the case of abnormal reflected power or abnormal dissipated power, the RF power of the RF power supply can be reduced more quickly to avoid overload of the RF power supply, thereby effectively improving the protection efficiency and safety of the RF power supply.

[0148] The following takes dissipated power protection as an example to specifically introduce the principle of how this method can quickly provide protection.

[0149] First, obtain the dissipated power threshold, the current bus voltage, the target bus current, the forward power feedback value and the reflected power feedback value, and calculate the dissipated power feedback value according to the above calculation method. Further, calculate the dissipated power deviation between the dissipated power threshold and the dissipated power feedback value, and determine the control amount increment corresponding to the dissipated power according to the obtained dissipated power deviation. Further, take the minimum value of the dissipated power control amount, the forward power control amount and the reflected power control amount in the previous cycle, that is, the target control amount as the control amount of the dissipated power in the previous cycle, calculate the sum of the control amount increment of the dissipated power and the target control amount, and obtain the control amount corresponding to the dissipated power in the current cycle. The calculation process of the forward power control amount and the reflected power control amount is similar to this and will not be described in detail. Determine the target control amount of the current cycle based on the obtained forward power control amount, the dissipated power control amount and the reflected power control amount (when the bus voltage threshold is provided, the bus voltage threshold should also be included). Finally, adjust the DC voltage of the DC power supply and adjust the RF power of the RF power supply according to the obtained target control amount.

[0150] According to the above content, assuming that the reflected power and dissipated power are normal in the previous cycle, the forward power control amount is used to control the RF power output, and the obtained forward power control amount is 1000, the dissipated power control amount and the reflected power control amount both reach the maximum value, such as 3000. It can be seen that the final control amount of this cycle is 1000.

[0151] In the current cycle, the dissipated power suddenly increases and is greater than the dissipated power threshold. The dissipated power protection mechanism needs to be executed immediately, that is, the dissipated power control amount is output as the minimum target control amount. Assuming that the dissipated power increment calculated in the current cycle is -200, according to the calculation method of the relevant technology, the sum of the dissipated power control amount of the previous cycle and the control amount increment of the current cycle is calculated as the dissipated power control amount of the current cycle, that is, 3000+(-200)=2800. Obviously, the obtained dissipated power control amount is still large and it is difficult to output it as the target control amount. Even if it is output as the target control amount, it is still difficult to effectively reduce the DC voltage and the corresponding RF power due to the large control amount value.

[0152] Compared with the above calculation method, this method calculates the sum of the dissipated power control increment and the target control amount determined in the previous cycle as the dissipated power control amount of the current cycle, and follows the previous example, that is, (-200) + 1000 = 800. Obviously, the method provided by this application can quickly reduce the dissipated power control amount, and then reduce the voltage of the DC power supply as the target control amount to control the RF power within a safe range. The triggering process of the reflected power protection mechanism is similar to this and will not be described in detail.

[0153] In the same vein, see Figure 8 As shown, another control amount calculation method provided by this embodiment includes the following steps.

[0154] S400: Obtain a control amount increment according to a deviation between a threshold value of a target parameter and a feedback value.

[0155] In an optional implementation, S400 may refer to Figure 7 The implementation of the relevant contents of S300 in the illustrated embodiment will not be repeated here.

[0156] S410. Determine the sum of the control amount increment and the preset reference control amount corresponding to the target parameter as the current control amount of the target parameter.

[0157] Compared with the previous embodiment in which the control amount of the current cycle is determined based on the control amount increment and the target control amount of the previous cycle, this embodiment provides a preset benchmark control amount for the target parameter. It can be understood that in order to achieve the purpose of quickly reducing the control amount of the target parameter, the value of the preset benchmark control amount should not be too large. In practical applications, the preset benchmark control amount can be determined based on the corresponding control amount under the safe operation state of the RF power supply, as long as it is smaller than the corresponding control amount under the safe operation state of the RF power supply.

[0158] The process of controlling the operation of the RF power supply and providing abnormal reflected power protection and abnormal dissipated power protection according to the method provided in this embodiment can be implemented by referring to the relevant contents of the aforementioned embodiments and will not be repeated here.

[0159] In combination with the execution process of the control method of the RF power supply provided in the above embodiments, it can be known that the calculation of the forward power control amount, the reflected power control amount and the dissipated power control amount are all performed according to a preset cycle, not in real time. Moreover, according to the operating characteristics of the DC power supply (the voltage regulation response speed is slow), the adjustment process of the bus voltage and the bias voltage is also performed according to a preset cycle. Based on this, for any of the above embodiments, when the DC power supply is performing bus voltage regulation, the calculation cycle of the reflected power control amount and the forward power control amount should be consistent with the adjustment cycle of the bus voltage. Correspondingly, when the DC power supply is performing bias voltage regulation, the calculation cycle of the reflected power control amount and the forward power control amount should be consistent with the adjustment cycle of the bias voltage. Since the acquisition cycle of the bus voltage and the DC current involved in the calculation process of the dissipated power control amount is relatively long (also because the process of the DC power supply regulating the bus voltage and the DC current is relatively long), the calculation cycle of the dissipated power control amount is longer than the calculation cycle of the reflected power control amount and the forward power control amount in the above two cases. In practical applications, the calculation cycles of the forward power control amount, the reflected power control amount and the dissipated power control amount can be set in combination with the above situation and factors such as the performance of the DC power supply.

[0160] It can be understood that the control method of the RF power supply provided in the above-mentioned embodiments of the present application is implemented according to a software algorithm. Compared with the hardware protection circuit implemented according to electronic components in the related art, it is not easily affected by electromagnetic field fluctuations and ambient temperature changes. The relevant parameters involved in the execution of the method can be changed at any time through the host computer, and thus it is applicable to different RF power supplies, with a wider range of applications and greater flexibility.

[0161] The control device of the radio frequency power supply provided by the present invention is introduced below. The control device of the radio frequency power supply provided by the present invention belongs to the same application concept as the control method of the radio frequency power supply provided by the embodiment of the present application, and can execute the control method of the radio frequency power supply provided by any embodiment of the present application, and has the corresponding functional modules and beneficial effects of executing the control method of the radio frequency power supply. For the technical details not described in detail in this embodiment, please refer to the control method of the radio frequency power supply provided by the embodiment of the present application, and will not be repeated here.

[0162] See also Fig. 9 The control device of the RF power supply provided in this embodiment includes a main control unit 10, wherein the main control unit 10 is connected to a DC power supply 20 in the RF power supply, and the DC power supply 20 is connected to a power amplifier circuit 30. The main control unit 10 adopts the control method provided in this application to control the bus voltage and bias voltage provided by the DC power supply 20 to the power amplifier circuit 30.

[0163] Specifically, the main control unit 10 is used to control one of the at least one pulse signal in each of the working cycles according to the first control mode;

[0164] The first control method: adjusts the bus voltage output to the RF power supply according to the current forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the RF power supply, and maintains the bias voltage output to the RF power supply unchanged.

[0165] Further, in the case where the RF power supply provides at least two pulse signals in each of the working cycles, the main control unit 10 is further configured to control the pulse signal with the largest forward power setting value among the at least two pulse signals according to the first control mode, and control the remaining pulse signals except the pulse signal with the largest forward power setting value according to the second control mode;

[0166] The second control mode is to adjust the bias voltage output to the RF power supply according to the current forward power feedback value and reflected power feedback value of the RF power supply, and maintain the bus voltage of the RF power supply unchanged.

[0167] For further information, see Fig.10 As shown, the present application provides another control device for radio frequency power supply, Fig. 9 On the basis of the illustrated embodiment, the main control unit 10 provided in this embodiment specifically includes:

[0168] A forward power control amount calculation unit 110 is used to obtain a forward power setting value and a forward power feedback value of a current RF power supply, and determine a forward power control amount according to a forward power deviation between the forward power setting value and the forward power feedback value;

[0169] A reflected power control amount calculation unit 120, configured to obtain a reflected power threshold and a reflected power feedback value of the current RF power supply, and determine a reflected power control amount according to a reflected power deviation between the reflected power threshold and the reflected power feedback value;

[0170] The dissipated power control amount calculation unit 130 is used to obtain the dissipated power threshold and the dissipated power feedback value of the current RF power supply, and determine the dissipated power control amount according to the dissipated power deviation between the dissipated power threshold and the dissipated power feedback value;

[0171] The dissipated power calculation unit 140 is used to calculate the dissipated power feedback value of the current RF power supply and provide the dissipated power feedback value to the dissipated power control amount calculation unit 130. It can be understood that the RF power supply is also provided with a sampling circuit 40 for collecting and feeding back Fig.10 The relevant parameters shown.

[0172] The bus voltage threshold determination unit 150 is used to determine the bus voltage threshold of the current RF power supply.

[0173] A comparison unit 160, configured to determine a first target control amount according to a forward power control amount, a reflected power control amount, a dissipated power control amount, and a bus voltage threshold;

[0174] The control unit 170 is used to adjust the bus voltage output to the RF power supply according to the first target control amount.

[0175] Furthermore, the comparison unit 160 is further configured to determine the minimum control amount among the forward power control amount and the reflected power control amount as the second target control amount;

[0176] The control unit 170 is further configured to adjust the bias voltage of the RF power supply according to the second target control amount.

[0177] Below Fig.10 The control device provided in the embodiment shown in the figure is taken as an example to describe in detail the output of the RF power supply. Fig.11 The specific process of the pulse signal shown in Figure 2. Fig.11 As shown, in any operation cycle, the RF power supply is required to provide two pulse signals, namely pulse signal 1 and pulse signal 2, wherein the forward power setting value of pulse signal 1 is greater than the forward power setting value of pulse signal 2. Based on this, the present application controls the RF power supply to output pulse signal 1 according to the first control method, and controls the RF power supply to output pulse signal 2 according to the second control method.

[0178] In the process of outputting pulse signal 1, the specific execution process is as follows:

[0179] The forward power control amount calculation unit 110 obtains the forward power setting value of the pulse signal 1 and the forward power feedback value fed back by the sampling circuit 40, and determines the forward power control amount of the pulse signal 1 based on the forward power deviation between the forward power setting value and the forward power feedback value;

[0180] The reflected power control amount calculation unit 120 obtains the reflected power threshold and the reflected power feedback value of the pulse signal 1, and determines the reflected power control amount of the pulse signal 1 according to the reflected power deviation between the reflected power threshold and the reflected power feedback value;

[0181] The dissipated power calculation unit 140 collects the DC voltage and DC current of the DC power supply 20, and at the same time, collects the forward power feedback value and the reflected power feedback value of the pulse signal 1 through the sampling circuit 40, calculates the dissipated power feedback value corresponding to the pulse signal 1 according to the obtained parameters, and finally outputs the obtained dissipated power feedback value to the dissipated power control amount calculation unit 120;

[0182] The power dissipation control amount calculation unit 120 obtains the power dissipation threshold and the power dissipation feedback value of the pulse signal 1, and determines the power dissipation control amount of the pulse signal 1 according to the power dissipation deviation between the obtained power dissipation threshold and the power dissipation feedback value;

[0183] The bus voltage threshold determination unit 150 determines the bus voltage threshold corresponding to the pulse signal 1 .

[0184] The comparison unit 160 takes the smallest value among the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold provided by the aforementioned related units as the first target control amount, and outputs it to the control unit 170 .

[0185] The control unit 170 adjusts the bus voltage output to the RF power supply according to the first target control amount, and maintains the bias voltage of the RF power supply unchanged.

[0186] The power amplifier circuit 30 outputs a pulse signal 1 based on the obtained driving signal and the DC voltage provided by the DC power supply 20 .

[0187] In the process of outputting pulse signal 2, the specific execution process is as follows:

[0188] The forward power control amount calculation unit 110 obtains the forward power setting value of the pulse signal 2 and the forward power feedback value fed back by the sampling circuit 40, and determines the forward power control amount of the pulse signal 2 based on the forward power deviation between the forward power setting value and the forward power feedback value;

[0189] The reflected power control amount calculation unit 120 obtains the reflected power threshold and the reflected power feedback value of the pulse signal 2, and determines the reflected power control amount of the pulse signal according to the reflected power deviation between the reflected power threshold and the reflected power feedback value;

[0190] The comparison unit 160 uses the smallest value of the forward power control amount and the reflected power control amount provided by the aforementioned related units as the second target control amount, and outputs it to the control unit 170.

[0191] The control unit 170 adjusts the bias voltage output to the RF power supply according to the second target control amount, and maintains the bus voltage of the RF power supply unchanged.

[0192] The power amplifier circuit 30 outputs a pulse signal 2 based on the obtained driving signal and the DC voltage provided by the DC power supply 20 .

[0193] It should be noted that, assuming that pulse signal 1 is output before pulse signal 2, when the RF power supply is controlled to output pulse signal 2, the bus voltage is maintained unchanged. At this time, the specific value of the bus voltage can be the bus voltage value of the RF power supply during the output of pulse signal 1. Correspondingly, assuming that pulse signal 2 is output before pulse signal 1, then the bus voltage when outputting pulse signal 2 can use the bus voltage value in the previous control cycle.

[0194] The present application also provides a radio frequency power supply, see Fig.12 As shown, the RF power supply provided in the present application includes a main controller 50 , a DC power supply 20 , a power amplifier circuit 30 and a sampling circuit 40 .

[0195] Combination Fig.12 As shown, the control end of the power amplifier circuit 30 receives the driving signal, the DC power supply 20 is used to provide a DC voltage for the power amplifier circuit 30, and the power amplifier circuit 30 converts the DC voltage into a pulse signal output according to the duty cycle corresponding to the pulse driving signal.

[0196] The sampling circuit 40 is connected to the output end of the power amplifier circuit 300, and can collect the forward power and reflected power of the RF power supply. After signal processing operations such as frequency calibration, it provides the main controller 50 with reflected power feedback values ​​and forward power feedback values.

[0197] The main controller 50 is connected to the DC power supply 20 and the sampling circuit 40 respectively. Based on obtaining the reflected power feedback value and the forward power feedback value provided by the sampling circuit 40, the main controller 50 also obtains the bus voltage and DC current of the DC power supply 20.

[0198] The main controller 50 is used to execute the control method of the radio frequency power supply provided by any of the above embodiments.

[0199] Furthermore, the present application also provides a semiconductor process equipment, which includes a process chamber and at least one RF power supply as provided in the above-mentioned embodiment, and the RF power supply is used to provide RF power to the process chamber to excite the process gas in the process chamber to generate plasma.

[0200] The semiconductor process equipment of the embodiment of the present application may be an inductively coupled plasma (ICP) device or a capacitively coupled plasma (CCP) device. The embodiment of the present application does not limit the type of semiconductor process equipment.

[0201] In some embodiments, this embodiment further provides a computer-readable storage medium, such as a floppy disk, an optical disk, a hard disk, a flash memory, a U disk, an SD (Secure Digital Memory Card) card, an MMC (Multimedia Card) card, etc., in which one or more instructions for implementing the above steps are stored, and when the one or more instructions are executed by one or more processors, the processors execute the control method of the radio frequency power supply described above. For the relevant specific implementation, please refer to the above description, which will not be repeated here.

[0202] In addition to the above-mentioned methods and devices, an embodiment of the present application may also be a computer program product, which includes computer program instructions. When the computer program instructions are executed by a processor, the processor executes the steps of the control method of the RF power supply according to various embodiments of the present application described in the above content of this specification.

[0203] The computer program product may be written in any combination of one or more programming languages ​​to write program codes for performing the operations of the embodiments of the present application, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" language or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0204] Those skilled in the art will appreciate that the contents disclosed in this disclosure may be subject to various modifications and improvements. For example, the various devices or components described above may be implemented by hardware, or by software, firmware, or a combination of some or all of the three.

[0205] In addition, although the present disclosure makes various references to certain units in the system according to embodiments of the present disclosure, any number of different units can be used and run on the client and / or server. The units are only illustrative, and different aspects of the system and method can use different units.

[0206] Flowcharts are used in this disclosure to illustrate the steps of the method according to the embodiments of the present disclosure. It should be understood that the preceding or following steps are not necessarily performed precisely in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may also be added to these processes.

[0207] Those skilled in the art will appreciate that all or part of the steps in the above method can be completed by instructing related hardware through a computer program, and the program can be stored in a computer-readable storage medium, such as a read-only memory, etc. Optionally, all or part of the steps in the above embodiment can also be implemented using one or more integrated circuits. Accordingly, each module / unit in the above embodiment can be implemented in the form of hardware or in the form of a software functional module. The present disclosure is not limited to any particular form of combination of hardware and software.

[0208] Unless otherwise defined, all terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present disclosure belongs. It should also be understood that terms such as those defined in common dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an idealized or highly formal sense, unless explicitly defined as such herein.

[0209] The above is an explanation of the present disclosure and should not be considered as a limitation thereof. Although several exemplary embodiments of the present disclosure are described, it will be readily understood by those skilled in the art that many modifications may be made to the exemplary embodiments without departing from the novel teachings and advantages of the present disclosure. Therefore, all such modifications are intended to be included within the scope of the present disclosure as defined in the claims. It should be understood that the above is an explanation of the present disclosure and should not be considered to be limited to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The present disclosure is defined by the claims and their equivalents.

Claims

1. A method for controlling a radio frequency power supply, characterized in that: The radio frequency power supply provides at least one pulse signal in each working cycle, and the control method includes: In each of the working cycles, one of the at least one pulse signal is controlled according to a first control method; The first control method: adjusts the bus voltage output to the RF power supply according to the current forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the RF power supply, and maintains the bias voltage output to the RF power supply unchanged.

2. The control method according to claim 1, characterized in that: The radio frequency power supply provides at least two pulse signals in each of the working cycles; Among the at least two pulse signals, the pulse signal with the largest forward power setting value is controlled according to the first control mode, and the remaining pulse signals except the pulse signal with the largest forward power setting value are controlled according to the second control mode; The second control mode is to adjust the bias voltage output to the RF power supply according to the current forward power feedback value and reflected power feedback value of the RF power supply, and maintain the bus voltage of the RF power supply unchanged.

3. The control method according to claim 1, characterized in that: The bus voltage output to the RF power supply is adjusted according to the forward power feedback value, the reflected power feedback value, the dissipated power feedback value and the bus voltage threshold of the current RF power supply, including: Obtaining a forward power setting value, a reflected power threshold, a dissipated power threshold, a forward power feedback value, a reflected power feedback value, a dissipated power feedback value, and a bus voltage threshold of the current RF power supply; Determining a forward power control amount according to a forward power deviation between the forward power setting value and the forward power feedback value; Determining a reflected power control amount according to a reflected power deviation between the reflected power threshold and the reflected power feedback value; Determining a dissipated power control amount according to a dissipated power deviation between the dissipated power threshold and the dissipated power feedback value; Determine a first target control amount according to the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold; The bus voltage output to the RF power supply is adjusted according to the first target control amount.

4. The control method according to claim 3, characterized in that: Determining a first target control amount according to the forward power control amount, the reflected power control amount, the dissipated power control amount, and the bus voltage threshold includes: The smallest value among the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold is determined as the first target control amount.

5. The control method according to claim 3, characterized in that: The bus voltage threshold is obtained, including: Determine a current proportionality coefficient according to a ratio of the reflected power feedback value to the forward power feedback value; The bus voltage threshold is determined according to the current proportionality coefficient and a predetermined corresponding relationship between the bus voltage threshold and the proportionality coefficient.

6. The control method according to claim 5, characterized in that: The predetermined corresponding relationship between the bus voltage threshold and the proportionality coefficient includes: When the proportionality coefficient is less than or equal to the first threshold value, the bus voltage threshold corresponding to the proportionality coefficient is the first voltage value; When the proportionality coefficient is greater than or equal to the second threshold, the bus voltage threshold corresponding to the proportionality coefficient is a second voltage value, and the second threshold is greater than the first threshold; When the proportionality coefficient is greater than the first threshold and less than the second threshold, the proportionality coefficient is inversely proportional to the bus voltage threshold.

7. The control method according to claim 1, characterized in that: Adjusting the bias voltage of the radio frequency power supply according to the forward power and the reflected power of the radio frequency power supply includes: Obtaining a forward power setting value, a reflected power threshold, a forward power feedback value, and a reflected power feedback value of the RF power supply; Determining a forward power control amount according to a forward power deviation between the forward power setting value and the forward power feedback value; Determining a reflected power control amount according to a reflected power deviation between the reflected power threshold and the reflected power feedback value; Determine the minimum control amount among the forward power control amount and the reflected power control amount as the second target control amount; The bias voltage of the RF power supply is adjusted according to the second target control amount.

8. A control device for a radio frequency power supply, characterized in that: The radio frequency power supply provides at least one pulse signal in each working cycle, and the control device includes: A main control unit, configured to control, in each of the working cycles, one of the at least one pulse signal according to a first control mode; The first control method: adjusts the bus voltage output to the RF power supply according to the current forward power feedback value, reflected power feedback value, dissipated power feedback value and bus voltage threshold of the RF power supply, and maintains the bias voltage output to the RF power supply unchanged.

9. The control device according to claim 8, characterized in that: The radio frequency power supply provides at least two pulse signals in each of the working cycles; The main control unit is configured to control, among the at least two pulse signals, the pulse signal with the largest forward power setting value according to the first control mode, and control the remaining pulse signals except the pulse signal with the largest forward power setting value according to the second control mode; The second control mode is to adjust the bias voltage output to the RF power supply according to the current forward power feedback value and reflected power feedback value of the RF power supply, and maintain the bus voltage of the RF power supply unchanged.

10. The control device of the radio frequency power supply according to claim 8, characterized in that: The main control unit includes: a forward power control amount calculation unit, a reflected power control amount calculation unit, a reflected power control amount calculation unit, a dissipated power control amount calculation unit, a comparison unit and a control unit, wherein: The forward power control amount calculation unit is used to obtain the current forward power setting value and the forward power feedback value of the RF power supply, and determine the forward power control amount according to the forward power deviation between the forward power setting value and the forward power feedback value; The reflected power control amount calculation unit is used to obtain the reflected power threshold and reflected power feedback value of the current RF power supply, and determine the reflected power control amount according to the reflected power deviation between the reflected power threshold and the reflected power feedback value; The dissipated power control amount calculation unit is used to obtain the current dissipated power threshold and dissipated power feedback value of the RF power supply, and determine the dissipated power control amount according to the dissipated power deviation between the dissipated power threshold and the dissipated power feedback value; The comparison unit is used to determine a first target control amount according to the forward power control amount, the reflected power control amount, the dissipated power control amount and the bus voltage threshold; The control unit is used to adjust the bus voltage output to the RF power supply according to the first target control amount.

11. The control device of the radio frequency power supply according to claim 10, characterized in that: The comparison unit is further used to determine the minimum control amount among the forward power control amount and the reflected power control amount as the second target control amount; The control unit is further configured to adjust the bias voltage of the RF power supply according to the second target control amount.

12. A radio frequency power supply, characterized in that: include: Main controller, power amplifier circuit and sampling circuit, wherein: The sampling circuit is connected to the power amplifier circuit; The main controller is connected to the power amplifier circuit and the sampling circuit respectively; The main controller is used to execute the control method of the radio frequency power supply according to any one of claims 1 to 7.

13. A semiconductor process equipment, characterized in that: include: A process chamber and at least one RF power supply as claimed in claim 12, wherein: The radio frequency power supply is used to provide radio frequency power to the process chamber to excite the process gas in the process chamber to generate plasma.

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