Radio frequency impedance matching method and system, semiconductor process equipment

Abstract

The embodiments of the present application provide a radio frequency impedance matching method and system, and semiconductor process equipment. The radio frequency impedance matching method is used to realize the ignition of the process chamber of the semiconductor process equipment through a radio frequency power supply and a matcher, and includes: obtaining the matching parameters and initial frequency sweep parameters in the process recipe; controlling the parameters of the capacitor assembly in the matcher to be the matching parameters; controlling the radio frequency power supply to automatically sweep the frequency with the initial frequency sweep parameters, so as to make the impedance of the radio frequency power supply equal to the impedance of the matcher and the process chamber, so as to ignite the process chamber. The embodiments of the present application realize that the radio frequency power supply can call the optimal initial frequency sweep parameters to realize the rapid ignition and matching of the process chamber, thereby not only greatly improving the ignition efficiency of the process chamber, but also avoiding the occurrence of ignition matching failure, thereby ensuring the repeatability and stability of ignition and matching, so as to greatly improve the consistency of process results.

Description

Technical Field

[0001] The present application relates to the field of semiconductor processing technology. Specifically, the present application relates to a radio frequency impedance matching method and system, and semiconductor process equipment. Background Art

[0002] At present, plasma is widely used in the production process of semiconductor devices. In the plasma etching system, the RF power supply transmits the RF energy to the process chamber through the matcher. In the process chamber, the RF energy excites the gas with a certain pressure into plasma. The excited plasma contains a large number of active particles such as electrons, ions, excited atoms, molecules and free radicals. These active particles interact with the wafer placed in the process chamber and exposed to the plasma environment, causing various physical and chemical reactions on the surface of the wafer material, thereby changing the surface properties of the material and completing the etching of the wafer or other process.

[0003] In the process of RF energy transmission, since the output impedance of the RF power supply is generally 50 ohms, the input impedance of the process chamber is generally a non-50 ohm impedance value with real impedance and imaginary impedance. Therefore, when the energy is directly transmitted to the process chamber, due to the impedance mismatch of the transmission path, the RF energy is reflected, resulting in the inability to normally excite the plasma in the process chamber. Therefore, it is necessary to insert a matcher between the RF power supply and the process chamber so that the input impedance of the rear end of the RF power supply is 50 ohms, which is convenient for the normal transmission of energy. However, in the prior art, when a matcher is used for matching, since the RF power supply is always a fixed frequency parameter of 13.56MHz, it completely relies on the matcher for ignition and matching, so that the entire matching process takes 0.5s or more, and the purpose of fast matching cannot be achieved. When using the RF power supply sweep frequency method for ignition matching, the matcher is completely in a fixed mode for at least a period of time during the sweep frequency period. At this time, the frequency stability range is large, and there are differences and non-repeatability. Furthermore, due to the characteristics of plasma, there will be unstable ignition areas in certain frequency points. When entering these specific areas, the ignition and matching time will be correspondingly lengthened, and even the RF power supply cannot jump out of the area, resulting in ignition and matching failure. Summary of the invention

[0004] In view of the shortcomings of the existing methods, the present application proposes a radio frequency impedance matching method and system, and semiconductor process equipment to solve the technical problems of the inability to quickly ignite and ignition matching failure in the prior art.

[0005] In the first aspect, an embodiment of the present application provides a radio frequency impedance matching method for realizing ignition of a process chamber of a semiconductor process equipment through a radio frequency power supply and a matcher, comprising: obtaining matching parameters and initial frequency sweep parameters in a process recipe, wherein the initial frequency sweep parameters are the starting frequency at which the radio frequency power supply starts automatic frequency sweeping; controlling parameters of a capacitor component in a matcher to be the matching parameters; and controlling the radio frequency power supply to start automatic frequency sweeping with the initial frequency sweep parameters, so as to make the impedance of the radio frequency power supply equal to the impedance of the matcher and the process chamber, so as to ignite the process chamber.

[0006] In one embodiment of the present application, before obtaining the matching parameters and the initial frequency sweep parameters in the process recipe, it also includes: querying the matching parameters and the initial frequency sweep parameters in the process recipe; if the matching parameters and the initial frequency sweep parameters are found in the process recipe, obtaining the matching parameters and the initial frequency sweep parameters.

[0007] In an embodiment of the present application, if the matching parameter and the initial frequency sweep parameter are not found in the process recipe, the matching parameter and the initial frequency sweep parameter are determined.

[0008] In one embodiment of the present application, determining the matching parameters includes: controlling the parameters of the capacitor component in the matcher to be preset parameters; when the RF power supply is the fixed frequency parameter, controlling the matcher to obtain the first capacitance parameter and the second capacitance parameter according to a matching algorithm; recording the first capacitance parameter and the second capacitance parameter as matching parameters, and storing them in the process recipe.

[0009] In one embodiment of the present application, determining the initial frequency sweep parameters includes: controlling the RF power supply to a fixed frequency parameter; when the matcher is in manual mode, setting the parameters of the capacitor component in the matcher to the first capacitance parameter and the second capacitance parameter; igniting the process chamber in a step-by-step manner according to the second capacitance parameter at a preset ratio to obtain the third capacitance parameter; recording the first capacitance parameter and the third capacitance parameter as ignition parameters, and storing them in the process recipe.

[0010] In one embodiment of the present application, the initial frequency sweep parameter is determined according to the matching parameter, the fixed frequency parameter and the ignition parameter.

[0011] In one embodiment of the present application, the initial frequency sweep parameters need to satisfy the following formula:

[0012] 2πf 0 *C2b=2πf 1 *C2a

[0013] f1 =f 0 *C2b / C2a

[0014] Wherein, f0 represents the fixed frequency parameter, f1 represents the initial frequency sweep parameter, C2a represents the second capacitance parameter, and C2b represents the third capacitance parameter.

[0015] In an embodiment of the present application, the fixed frequency parameter is 400 KHz, 2 MHz, 13.56 MHz or 40 MHz.

[0016] In the second aspect, an embodiment of the present application provides a radio frequency impedance matching system, comprising: a control device, a matcher and a radio frequency power supply; the control device is electrically connected to the matcher and the radio frequency power supply, and the control device is used to obtain matching parameters and initial frequency sweep parameters in a process recipe; and control the parameters of the capacitor assembly in the matcher to be the matching parameters; and control the radio frequency power supply to start automatic frequency sweeping with the initial frequency sweep parameters, so that the impedance of the radio frequency power supply is equal to the impedance of the matcher and the process chamber, so as to start the process chamber.

[0017] In a third aspect, an embodiment of the present application provides a semiconductor process equipment, including: a process chamber and a radio frequency impedance matching system, wherein the radio frequency impedance matching system is used to perform the radio frequency impedance matching method provided in the first aspect.

[0018] The beneficial technical effects brought about by the technical solution provided by the embodiment of the present application are:

[0019] The embodiment of the present application presets the matching parameters of the matcher and the starting frequency sweep parameters of the RF power supply in the process recipe, so that the matcher does not need to be matched automatically, and the RF power supply can call the optimal initial frequency sweep parameters to achieve rapid ignition and matching of the process chamber, thereby not only greatly improving the ignition efficiency of the process chamber, but also avoiding the occurrence of ignition matching failures, thereby ensuring the repeatability and stability of ignition and matching, and greatly improving the consistency of process results.

[0020] Additional aspects and advantages of the present application will be partially given in the following description, which will become apparent from the following description, or will be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0022] Figure 1 A schematic diagram of a flow chart of a radio frequency impedance matching method provided in an embodiment of the present application;

[0023] Figure 2 A schematic diagram of the structure of a radio frequency impedance matching system provided in an embodiment of the present application;

[0024] Figure 3 A schematic diagram showing the effect of changes in a capacitor assembly on impedance in a matching device provided in an embodiment of the present application;

[0025] Figure 4 A schematic diagram of a RF impedance matching method for realizing ignition and matching process provided in an embodiment of the present application;

[0026] Figure 5 It is a schematic diagram of frequency variation in the radio frequency impedance method in the prior art. DETAILED DESCRIPTION

[0027] The present application is described in detail below, and examples of embodiments of the present application are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar components or components with the same or similar functions. In addition, if the detailed description of the known technology is unnecessary for the features of the present application shown, it will be omitted. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be interpreted as limiting the present application.

[0028] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art to which this application belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with those in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0029] In the matching process of the prior art, there is a process in which the plasma ignites first and then matches. Especially for the inductively coupled plasma technology (ICP), there is an EH mode jump in the plasma ignition process, that is, the ICP discharge process is often accompanied by capacitive coupled discharge (CCP). As the input power begins to be fed into the plasma, the plasma is excited and begins to work in the E mode state. At this time, the entire discharge is mainly maintained by the axial electric field generated by the potential difference at both ends of the coil. As the input power continues to increase until it exceeds a certain threshold, the plasma state will suddenly jump into the H mode. At this time, the discharge is mainly maintained by the toroidal electric field generated by the Faraday effect, and the main reason for the EH mode jump is due to the nonlinearity of the plasma absorption power. When a matcher is used for matching, since the RF power supply is always a fixed frequency parameter of 13.56MHz, it is completely dependent on the matcher for ignition and matching, so that the entire matching process takes 0.5s or more, and the purpose of fast matching cannot be achieved. When using the RF power supply sweep frequency method for ignition matching, the matcher is completely in a fixed mode for at least a period of time during the sweep period. At this time, the frequency stability range is large, and there are differences and non-repeatability. Figure 5 As shown in the figure, under certain process conditions, when the RF power source is swept, different ignition and matching frequency points will appear, which will reduce the reflected power, such as at 13.1MHz and 13.6MHz. Different matching frequency points will also have a certain impact on the process results. In addition, due to the characteristics of plasma, there will be unstable ignition areas in certain frequency point areas, such as Figure 5 As shown in the 13.4MHz to 13.5MHz range, when entering these specific areas, the ignition and matching time will be correspondingly extended, and even the RF power supply cannot jump out of this area, resulting in ignition and matching failure.

[0030] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments.

[0031] The embodiment of the present application provides a radio frequency impedance matching method for realizing ignition of a process chamber of a semiconductor process equipment through a radio frequency power supply and a matching device. The flow chart of the method is as follows: Figure 1 As shown, the method includes:

[0032] S1: Obtain matching parameters and initial frequency sweep parameters in the process recipe. The initial frequency sweep parameters are the starting frequency at which the RF power source starts automatic frequency sweeping.

[0033] S2: Control the parameters of the capacitor components in the matching device as matching parameters;

[0034] S3: Control the RF power supply to start automatic frequency sweep with initial frequency sweep parameters, so as to make the impedance of the RF power supply equal to the impedance of the matcher and the process chamber, so as to start the process chamber.

[0035] Combined with Figures 2 to 3 As shown, the embodiment of the present application is mainly applied to the process chamber 100 of the semiconductor process equipment, and is used to realize the rapid ignition and matching of the process chamber 100, so that the plasma in the process chamber 100 can be quickly ignited to avoid entering the plasma unstable area, thereby realizing stable repeatability in the process matching process. Specifically, before starting the process, the control device (not shown in the figure) can obtain the matching parameters and the initial frequency sweep parameters from the process recipe. The control device can be, for example, a lower computer, a single chip microcomputer or a lower computer of the semiconductor process equipment, which can be used to store the process recipe of the current process, but the embodiment of the present application is not limited to this. The control device can set the parameters of the capacitor assembly 21 in the matcher 2 to the matching parameters, or can manually set the parameters of the capacitor assembly 21 in the matcher 2 to the matching parameters, so the embodiment of the present application is not limited to this. The control device can control the RF power supply 1 to start automatic frequency sweeping with initial frequency sweeping parameters, that is, the initial frequency sweeping parameters are the starting frequency of the RF power supply 1 to start automatic frequency sweeping. When the RF power supply 1 starts to load RF power, since the matcher 2 has been set to the matching parameters at this time, rapid ignition can be achieved, and the RF power supply 1 can also be quickly adjusted to a fixed frequency parameter after rapid ignition, thereby achieving rapid ignition and matching of the process chamber 100.

[0036] The embodiment of the present application presets the matching parameters of the matcher and the starting frequency sweep parameters of the RF power supply in the process recipe, so that the matcher does not need to be matched automatically, and the RF power supply can call the optimal initial frequency sweep parameters to achieve rapid ignition and matching of the process chamber, thereby not only greatly improving the ignition efficiency of the process chamber, but also avoiding the occurrence of ignition matching failures, thereby ensuring the repeatability and stability of ignition and matching, and greatly improving the consistency of process results.

[0037] In one embodiment of the present application, Figure 1As shown, before obtaining the matching parameters and initial frequency sweep parameters in the process formula, it also includes: querying the matching parameters and initial frequency sweep parameters in the process formula; if the matching parameters and initial frequency sweep parameters are found in the process formula, obtaining the matching parameters and initial frequency sweep parameters. Specifically, before executing the current process, query whether there are matching parameters and initial frequency sweep parameters in the process formula, that is, determine whether the current process has been executed before. If the matching parameters and initial frequency sweep parameters are found in the process formula, it means that the current process has been executed before, so the matching parameters and initial frequency sweep parameters in the process formula are directly obtained, and the above steps S1 and S2 are executed according to the above matching parameters and initial frequency sweep parameters. The above design enables the embodiment of the present application to directly call the optimal initial frequency sweep parameters, so that the process chamber 100 can be quickly started and matched.

[0038] In one embodiment of the present application, Figures 1 to 3 As shown, if the matching parameters and the initial frequency sweep parameters are not found in the process recipe, the matching parameters and the initial frequency sweep parameters are determined.

[0039] Optionally, determining the matching parameters includes: controlling the parameters of the capacitor component 21 in the matcher 2 to be preset parameters; when the RF power supply 1 is a fixed frequency parameter, controlling the matcher 2 to obtain the first capacitance parameter C1a and the second capacitance parameter C2a during matching according to the matching algorithm; recording the first capacitance parameter C1a and the second capacitance parameter C2a as matching parameters, and storing them in the process recipe.

[0040] Optionally, determining the initial frequency sweep parameters includes: controlling the RF power supply 1 to a fixed frequency parameter; when the matcher 2 is in manual mode, setting the parameters of the capacitor assembly 21 in the matcher 2 to a first capacitance parameter C1a and a second capacitance parameter C2a; adjusting the second capacitance parameter C2a in a stepwise manner according to a preset ratio to ignite the process chamber 100 to obtain a third capacitance parameter C2b; recording the first capacitance parameter C1a and the third capacitance parameter C2b as ignition parameters, and storing them in the process recipe.

[0041] like Figures 1 to 3 As shown, before executing the current process, it is queried whether there are matching parameters and initial frequency sweep parameters in the process recipe, that is, it is determined whether the current process has been executed before. If the matching parameters and initial frequency sweep parameters are not found in the process recipe, it means that the current process has not been executed before, so it is necessary to re-determine the first capacitance parameter C1a, the second capacitance parameter C2a and the third capacitance parameter C2b, and calculate and determine the initial frequency sweep parameters according to the method in the above embodiment. Specifically, when the matching parameters and initial frequency sweep parameters in the current process recipe are not found, the control device can first control the capacitor assembly 21 in the matcher 2 to be the preset parameters, and the first capacitor C 1 and the second capacitor C2 Adjust to any commonly used preset parameters, for example, the preset parameters of both are 50%. At this time, the RF power supply 1 is a fixed frequency parameter and does not perform frequency sweeping. In order to obtain the initial frequency sweeping parameters, the matching time can be ignored. Then control the matcher 2 to use the automatic matching function to find the matching position. For example, after loading the RF power, use the existing matching algorithm to perform automatic matching. When the matching is completed, the controller can automatically record the first capacitor C 1 and the second capacitor C 2 The first capacitance parameter C1a and the second capacitance parameter C2a are obtained by controlling the matcher 2 according to the matching algorithm; the first capacitance parameter C1a and the second capacitance parameter C2a are recorded as matching parameters and stored in the process recipe.

[0042] Further, after stopping loading the RF power, the control device can set the matcher 2 to the manual mode and set the first capacitor C 1 and the second capacitor C 2 The first capacitance parameter C1a and the second capacitance parameter C2a are set respectively. After the RF power is loaded again, the second capacitance parameter C2a is gradually fine-tuned with a step size of 0.1%. 2 Parameters, until the ignition, record the second capacitor C 2 The third capacitance parameter C2b is obtained by adjusting the second capacitance parameter C2a in a step-by-step manner by a preset ratio to start the process chamber 100, so as to obtain the third capacitance parameter C2b. The first capacitance parameter C1a and the third capacitance parameter C2b are recorded as the starting parameters and stored in the process recipe. The initial sweep frequency value f is finally obtained by performing corresponding calculations through the second capacitance parameter C2a and the third capacitance parameter C2b. 1 After completing the above steps, you can directly call the matching parameters and initial frequency sweep parameters from the process recipe when executing the process.

[0043] like Figures 1 to 3 As shown, the matching parameters may include a first capacitor C 1 The first capacitance parameter, and the second capacitor C 2 The second capacitance parameters of the above two capacitance parameters are obtained when the RF power supply 1 is a fixed frequency parameter and the matching device 2 automatically matches the process chamber 100. In the same case, the second capacitor C 2 The second capacitor C 2The third capacitance parameter is set, that is, the second capacitance parameter is adjusted to start the process chamber 100 to obtain the third capacitance parameter, so as to use the first capacitance parameter and the third capacitance parameter as starting parameters, thereby further improving the frequency scanning efficiency of the RF power supply 1, and further improving the starting and matching efficiency of the process chamber 100.

[0044] Further, when the RF power source 1 starts to sweep the frequency with the initial sweep frequency parameter, the capacitor component 21 in the matcher 2 is set to the matching parameter, that is, the first capacitor C 1 is the first capacitance parameter, and the second capacitor C 2 is the second capacitance parameter, so that the RF power source 1 can return to the fixed frequency parameter when the frequency sweep is finished, for example, the fixed frequency parameter takes a value of 13.56MHz. For the commonly used L-type matching device 2 structure, the frequency change when the RF power source 1 is swept can basically cover the position change of the capacitor component 21 within a certain range, for example Figure 2 The second capacitor C shown in 2 The corresponding impedance of the RF power supply 1 can be matched to the impedance Z at the back end. L The following formula is used for calculation:

[0045]

[0046] Combined with reference Figure 3 It can be seen that when ωC 1 and ωC 2 When the impedance imaginary part changes, the impedance 2 is more sensitive to changes in ωC 2 When the change is very small, the imaginary part of the impedance changes dramatically, while ωC 1 Relative change and ωC 2 When C 1 and C 2 The value remains unchanged, and the ignition matching is achieved only by frequency sweeping through the RF power supply 1, that is, when ω=2πf is changed, it is equivalent to covering the second capacitor C 2 The imaginary part of the impedance is matched by the change of ωC, while the real part of the impedance is matched by ωC 1 The real part of the back-end impedance generally changes within a very small range, and the main change comes from the change of the imaginary part of the impedance. Therefore, the above design is adopted, and only the second capacitor C 2 The second capacitance parameter of the RF power source 1 is adjusted to obtain the third capacitance parameter to start the process chamber 100, and the second capacitor C is equivalently replaced by the RF power source 1 in an automatic frequency sweeping manner. 2The parameters of the embodiment of the present application are changed, so that the logic of the embodiment of the present application is simpler, so as to further improve the ignition efficiency of the process chamber 100, and also prevent the RF power supply from entering the unstable ignition area, thereby greatly improving the success rate of ignition of the process chamber 100. It should be noted that the embodiment of the present application does not limit the specific structure of the matcher 2, for example, the matcher 2 can also adopt a π-type or T-type structure. Therefore, the embodiment of the present application is not limited to this, and those skilled in the art can adjust the settings according to actual conditions.

[0047] In one embodiment of the present application, Figures 1 to 3 As shown, the initial frequency sweep parameters are determined according to the matching parameters, the fixed frequency parameters and the ignition parameters. Specifically, the matching parameters are the first capacitance parameters and the second capacitance parameters obtained by the matching device 2 in an automatic matching manner, that is, the first capacitor C in the matching device 2 1 and the second capacitor C 2 The process recipe also stores the ignition parameters, which are also obtained by the matcher 2 in an automatic matching manner, that is, the first capacitor C in the matcher 2. 1 and the second capacitor C 2 Parameters when the process chamber 100 is ignited. The initial frequency sweep parameters are determined according to the matching parameters, the fixed frequency parameters and the ignition parameters, that is, the initial frequency sweep parameters are calculated according to the ignition and matching path of the capacitor assembly 21 to achieve rapid ignition and matching of the process chamber 100. However, the embodiment of the present application does not limit the specific method of obtaining the ignition parameters, for example, the ignition parameters can be obtained manually. Therefore, the embodiment of the present application is not limited to this, and those skilled in the art can adjust the settings according to actual conditions.

[0048] In one embodiment of the present application, Figures 1 to 3 As shown, the initial sweep frequency parameters need to satisfy the following formula:

[0049] 2πf 0 *C2b=2πf 1 *C2a

[0050] f 1 =f 0 *C2b / C2a

[0051] Among them, f 0 Characterized as a fixed frequency parameter, f 1 C2a is characterized as the initial frequency sweep parameter, C2a is characterized as the second capacitance parameter, and C2b is characterized as the third capacitance parameter.

[0052] Optionally, the fixed frequency parameter is 400KHz, 2MHz, 13.56MHz or 40MHz. Specifically, when the RF power source 1 adopts a fixed frequency parameter of f0 When the matching device 2 obtains the matching parameters through automatic matching, that is, the second capacitor C 2 is the second capacitance parameter C2a; and the ignition parameter is obtained, that is, the second capacitor C 2 is the third matching parameter, and the initial frequency sweep parameter needs to satisfy the above formula. When the RF power source 1 starts to automatically sweep the frequency, the RF power source 1 can be set to the initial frequency sweep parameter, and the matcher 2 can be set to the matching parameter. The above design enables the embodiment of the present application to be applicable to different processes, thereby greatly improving the applicability and scope of application, and can also determine the repeatability and stability of the process.

[0053] In a specific embodiment, when the fixed frequency parameter of the RF power source 1 is f 0 When the frequency is 13.56MHz, the second capacitance parameter C2a in the matching parameter is 250pF, and the third capacitance parameter C2b in the ignition parameter is 240pF, the corresponding initial frequency sweep parameter f can be calculated according to the above formula. 1 It should be 13.02MHz. However, the present embodiment does not limit the fixed frequency parameter f 0 For example, the value can also be set to 400KHz, 2MHz or 40MHz, and those skilled in the art can adjust the setting according to the actual situation. 1 Stored in the process recipe, each time the process starts, the RF power supply 1 can be pre-run to the initial sweep frequency parameter f 1 At the starting point, after the RF power source 1 loads power to the matching device 2 and the process chamber 100, the RF power source 1 will be at the initial frequency sweep parameter f 1 The starting point is the automatic frequency sweep matching. Since the initial frequency sweep parameter f 1 The ignition condition has been met, so the RF power supply 1 will quickly adjust to the matching state, that is, the fixed frequency parameter is f 0 , achieving rapid ignition and matching of the process chamber 100. The matching flow chart of the specific process can be referred to as follows Figure 4 As shown. It can be seen that by calling the optimal initial sweep frequency parameters, rapid ignition can be achieved, and the matching repeatability and stability can be guaranteed, thereby greatly improving the consistency of process results.

[0054] Based on the same inventive concept, an embodiment of the present application provides a radio frequency impedance matching system, including: a control device, a matcher and a radio frequency power supply; the control device is electrically connected to the matcher and the radio frequency power supply, and the control device is used to obtain matching parameters and initial frequency sweep parameters in a process recipe; and control the parameters of the capacitor assembly in the matcher to be matching parameters; and control the radio frequency power supply to start automatic frequency sweep with the initial frequency sweep parameters, so that the impedance of the radio frequency power supply is equal to the impedance of the matcher and the process chamber, so as to start the process chamber.

[0055] Based on the same inventive concept, an embodiment of the present application provides a semiconductor process equipment, including: a process chamber and a radio frequency impedance matching system, and the radio frequency impedance matching system is used to perform the radio frequency impedance matching method provided in the above embodiments.

[0056] By applying the embodiments of the present application, at least the following beneficial effects can be achieved:

[0057] The embodiment of the present application presets the matching parameters of the matcher and the starting frequency sweep parameters of the RF power supply in the process recipe, so that the matcher does not need to be matched automatically, and the RF power supply can call the optimal initial frequency sweep parameters to achieve rapid ignition and matching of the process chamber, thereby not only greatly improving the ignition efficiency of the process chamber, but also avoiding the occurrence of ignition matching failures, thereby ensuring the repeatability and stability of ignition and matching, and greatly improving the consistency of process results.

[0058] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

[0059] Those skilled in the art will appreciate that the various operations, methods, steps, measures, and schemes in the processes discussed in this application may be alternated, altered, combined, or deleted. Further, other steps, measures, and schemes in the various operations, methods, and processes discussed in this application may also be alternated, altered, rearranged, decomposed, combined, or deleted. Further, the steps, measures, and schemes in the prior art that are similar to those disclosed in this application may also be alternated, altered, rearranged, decomposed, combined, or deleted.

[0060] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0061] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0062] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0063] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0064] It should be understood that, although the steps in the flowchart of the accompanying drawings are displayed in sequence as indicated by the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least a part of the steps in the flowchart of the accompanying drawings may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a part of the sub-steps or stages of other steps.

[0065] The above description is only a partial implementation method of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A radio frequency impedance matching method for realizing ignition of a process chamber of a semiconductor process equipment through a radio frequency power supply and a matching device, characterized in that: include: Query the matching parameters and initial frequency sweep parameters in the process recipe; When the matching parameter and the initial frequency sweep parameter are found in the process recipe, the matching parameter and the initial frequency sweep parameter in the process recipe are obtained, wherein the initial frequency sweep parameter is the starting frequency at which the RF power source starts automatic frequency sweeping; Controlling the parameters of the capacitor assembly in the matching device to be the matching parameters; The RF power source is controlled to start automatic frequency sweeping with the initial frequency sweeping parameters, so as to make the impedance of the RF power source equal to the impedance of the matcher and the process chamber, so as to start the process chamber.

2. The radio frequency impedance matching method according to claim 1, characterized in that: The matching parameters and the initial frequency sweep parameters in the process recipe are the matching parameters and the optimal initial frequency sweep parameters corresponding to the process recipe pre-stored in the process recipe.

3. The radio frequency impedance matching method according to claim 1, characterized in that: If the matching parameter and the initial frequency sweep parameter are not found in the process recipe, the matching parameter and the initial frequency sweep parameter are determined.

4. The radio frequency impedance matching method according to claim 3, characterized in that: The determining of the matching parameters comprises: Controlling the parameters of the capacitor assembly in the matching device to be preset parameters; When the RF power source has fixed frequency parameters, controlling the matcher to obtain the first capacitance parameter and the second capacitance parameter during matching according to a matching algorithm; The first capacitance parameter and the second capacitance parameter are recorded as matching parameters and stored in the process recipe.

5. The radio frequency impedance matching method according to claim 4, characterized in that: The determining of the initial frequency sweep parameters comprises: Controlling the radio frequency power supply to the fixed frequency parameter; When the matcher is in manual mode, setting parameters of the capacitor component in the matcher to the first capacitance parameter and the second capacitance parameter; Adjusting the second capacitance parameter in a step-by-step manner by a preset ratio to ignite the process chamber to obtain a third capacitance parameter; The first capacitance parameter and the third capacitance parameter are recorded as ignition parameters and stored in the process recipe.

6. The radio frequency impedance matching method according to claim 5, characterized in that: The initial frequency sweep parameter is determined according to the matching parameter, the fixed frequency parameter and the ignition parameter.

7. The radio frequency impedance matching method according to claim 6, characterized in that: The following formula needs to be satisfied to determine the initial frequency sweep parameters: 2πf0*C2b=2πf1*C2a f1=f0*C2b / C2a Wherein, f0 represents the fixed frequency parameter, f1 represents the initial frequency sweep parameter, C2a represents the second capacitance parameter, and C2b represents the third capacitance parameter.

8. The radio frequency impedance matching method according to any one of claims 5 to 7, characterized in that: The fixed frequency parameter is 400 KHz, 2 MHz, 13.56 MHz or 40 MHz.

9. A radio frequency impedance matching system, characterized in that: include: Control device, matching device and radio frequency power supply; The control device is electrically connected to the matcher and the radio frequency power supply, and the control device is used to query matching parameters and initial frequency sweep parameters in the process recipe; When the control device inquires the matching parameter and the initial frequency sweep parameter in the process recipe, the control device is further used to obtain the matching parameter and the initial frequency sweep parameter in the process recipe; and control the parameters of the capacitor component in the matcher to be the matching parameter; And controlling the RF power supply to start automatic frequency sweeping with the initial frequency sweeping parameters, so that the impedance of the RF power supply is equal to the impedance of the matcher and the process chamber, so as to ignite the process chamber.

10. A semiconductor process equipment, characterized in that: include: A process chamber and a radio frequency impedance matching system, wherein the radio frequency impedance matching system is used to perform any radio frequency impedance matching method as claimed in claims 1 to 8.

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