Radio frequency match, apparatus, device, and plasma profile adjustment method

Abstract

This application provides a radio frequency matching device, apparatus, equipment, and plasma distribution adjustment method, relating to the field of semiconductor equipment technology. The radio frequency matching device is applied to a plasma processing equipment, which includes a process chamber, a radio frequency source, a first coil, and a second coil. The radio frequency source, the first coil, and the second coil are connected in series and then connected to a ground terminal. The radio frequency matching device includes a first variable capacitor connected between the node between the first coil and the second coil and the ground terminal. The first variable capacitor is used to adjust the ratio of the radio frequency current generated by the radio frequency source flowing through the first coil and the second coil, so as to adjust the magnetic field distribution generated by the first coil and the second coil, thereby controlling the plasma distribution in the process chamber and meeting the differentiated requirements for plasma distribution.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor equipment technology, and in particular to a radio frequency matching device, apparatus, equipment and plasma distribution adjustment method. Background Technology

[0002] Semiconductor manufacturing processes are extremely complex. Temperature, pressure, gas flow rate, and radio frequency (RF) power all directly affect plasma density and distribution, thus influencing process performance. Furthermore, since plasma is generated by coupling RF source energy into the process chamber via coils or chucks, plasma density uniformity is significantly affected by the energy coupling method. On one hand, this non-uniformity can cause problems such as inconsistent etching rates, uneven film thickness, and inadequate cleaning. On the other hand, this non-uniformity can also achieve different process effects. For example, by utilizing plasma non-uniformity within the process chamber, etching can be achieved in the central region and deposition in the edge regions of the same chamber, or different cleaning effects can be achieved in different areas of the process chamber. Therefore, how to adjust plasma density distribution to optimize process performance is a problem that urgently needs to be solved by engineers. Summary of the Invention

[0003] This application provides a radio frequency matching device, apparatus, equipment, and plasma distribution adjustment method, which can adjust the plasma density distribution in the cavity by adjusting the ratio of the current flowing through the first coil to the current flowing through the second coil, thereby meeting the differentiated requirements for plasma distribution.

[0004] In a first aspect, this application provides a radio frequency (RF) matching device applied to a plasma processing apparatus. The plasma processing apparatus may include a process chamber, an RF source, a first coil, and a second coil, wherein the RF source, the first coil, and the second coil are connected in series and then connected to a ground terminal. The RF matching device may include a first variable capacitor, which is connected between the node between the first coil and the second coil and the ground terminal. Here, the first variable capacitor can be used to adjust the ratio of the RF current generated by the RF source flowing through the first coil and the second coil, thereby adjusting the magnetic field distribution generated by the first coil and the second coil, and thus controlling the plasma distribution within the process chamber.

[0005] It should be understood that since the first variable capacitor is connected between the node between the first and second coils and the ground terminal, the current flowing through the first coil is split at the node. Specifically, a portion of the current flowing through the first coil passes through the branch containing the second coil, while the other portion passes through the branch containing the first variable capacitor. Furthermore, the radio frequency (RF) current emitted by the RF power supply flows sequentially through the first and second coils, generating a magnetic field around them, which in turn excites the reactive gas in the process chamber into a plasma state. It is worth noting that the larger the current flowing through the coils, the stronger the magnetic field generated by the coils, and the higher the plasma density. Based on this, when the capacitance value of the first variable capacitor changes, the impedance of the branch containing the first variable capacitor changes, thereby adjusting the ratio of RF current flowing through the first and second coils to regulate the magnetic field distribution generated by the first and second coils, thus controlling the plasma distribution in the process chamber. Therefore, changing the capacitance value of the first variable capacitor can alter the plasma distribution in the process chamber without changing the RF power emitted by the RF source, adapting to the differentiated plasma distribution requirements of different processes and improving the flexibility of process development.

[0006] In a first possible implementation of the first aspect, the RF matching unit may further include a second variable capacitor connected between the second coil and the ground terminal. The second variable capacitor is used to work with the first variable capacitor to adjust the ratio of the RF current generated by the RF source flowing through the first coil and the second coil, so as to adjust the magnetic field distribution generated by the first coil and the second coil, thereby regulating the plasma distribution in the process chamber.

[0007] It should be understood that when the capacitance value of at least one of the first and second variable capacitors changes, the ratio of radio frequency current flowing through the first and second coils also changes, thereby adjusting the magnetic field distribution generated by the first and second coils, and thus controlling the plasma distribution within the process chamber. Therefore, adding a second variable capacitor allows for flexible adjustment of the capacitance values ​​of the first and / or second variable capacitors according to process requirements, achieving different plasma distributions based on the desired process effect.

[0008] Secondly, this application provides a radio frequency (RF) coupling device, which includes an RF source, a first coil, a second coil, and an RF matching device as described in the first aspect or any possible embodiment of the first aspect. The RF source, the first coil, and the second coil are connected in series to form an RF current path. The first variable capacitor of the RF matching device is connected between a node between the first and second coils and a ground terminal, and is used to adjust the capacitance value of the first variable capacitor to regulate the ratio of the RF current generated by the RF source flowing through the first and second coils, thereby controlling the plasma distribution.

[0009] In conjunction with the second aspect, in the first possible implementation, the plasma processing equipment may further include a fixed capacitor connected between the second coil and the grounding terminal. It should be understood that the second coil is grounded through the fixed capacitor, meaning that the end of the second coil connected to the grounding terminal maintains a high potential relative to ground. This is beneficial for ignition in the process chamber, expanding the ignition window while also reducing the risks of other abnormal arc discharges or sparking, parasitic ignition, etc.

[0010] Thirdly, this application provides a plasma processing apparatus, which may include a process chamber and a radio frequency coupling device as described in any of the possible embodiments of the first or second aspect. The radio frequency coupling device may be disposed outside the process chamber and is used to couple radio frequency energy into the process chamber via electromagnetic induction to excite and regulate the plasma distribution.

[0011] Fourthly, this application provides a plasma distribution adjustment method applicable to a plasma processing device. The plasma processing device may include a process chamber, an RF matching unit, a first coil, and a second coil. The RF matching unit may include a first variable capacitor connected between a node between the first coil and the second coil and a ground terminal. The method includes: acquiring current processing information of the workpiece to be processed; determining the target plasma distribution required in the process chamber based on the current processing information; determining the target current ratio between the first coil and the second coil according to the target plasma distribution; and adjusting the capacitance value of the first variable capacitor according to the target current ratio so that the current ratio between the first coil and the second coil reaches the target current ratio, thereby regulating the plasma distribution in the process chamber.

[0012] It should be understood that by adding a first variable capacitor between the node between the first coil and the second coil and the ground terminal, the plasma distribution in the process chamber can be changed by adjusting the capacitance value of the first variable capacitor without changing the radio frequency power emitted by the radio frequency source. This allows for flexible control of the plasma distribution, meets the differentiated requirements of different processes for plasma distribution, and optimizes the process effect.

[0013] In conjunction with the fourth aspect, in a first possible implementation, determining the target current ratio of the first coil to the second coil based on the target plasma distribution includes: obtaining the required magnetic field distribution within the process chamber based on the target plasma distribution; and determining the target current ratio of the first coil to the second coil corresponding to the required magnetic field distribution based on the required magnetic field distribution, the geometric positions of the first coil and the second coil, and their electromagnetic coupling characteristics.

[0014] It should be understood that by inverting the target plasma distribution into the required magnetic field distribution within the process chamber, precise control over the plasma distribution pattern is achieved, effectively improving the yield and consistency of the workpieces to be processed. Simultaneously, it can adapt to the differentiated plasma distribution requirements of various processes, enhancing the flexibility of process development.

[0015] In conjunction with the fourth aspect or the first possible implementation of the fourth aspect, in the second possible implementation, the aforementioned current processing information includes at least one of the following: etching rate of the workpiece to be processed, film thickness uniformity, and edge contour morphology. It should be understood that the etching rate can be used for feedback control to adjust the etching rate in real time, thereby improving etching accuracy. Film thickness uniformity can reflect whether there are problems such as uneven airflow distribution, uneven plasma density, or abnormal temperature distribution of the electrostatic chuck within the process chamber. Edge contour morphology refers to the shape, angle, undercut condition of the sidewalls of the etched pattern, and the physical morphology of the chamfered edges at the microstructural level, and can be used to determine whether a cleaning process needs to be triggered.

[0016] In conjunction with the second possible implementation of the fourth aspect, in the third possible implementation, the aforementioned current processing information may include the real-time plasma distribution within the process chamber. It should be understood that the real-time plasma distribution can provide feedback on the current plasma distribution within the process chamber, thereby determining whether adjustment of the current plasma distribution within the process chamber is necessary.

[0017] In conjunction with the third possible implementation of the fourth aspect, in the fourth possible implementation, the aforementioned current processing information may further include process requirements. These process requirements may include etching requirements, deposition requirements, or surface cleaning requirements, as well as target plasma distributions corresponding to each of these requirements. Here, the process requirements determine the energy state, chemical properties, and physical directionality of the plasma. By using the target plasma distributions corresponding to the etching, deposition, and surface cleaning requirements, the plasma distribution within the current process chamber can be adjusted in real time to ensure that the plasma distribution within the current process chamber meets the process requirements.

[0018] In conjunction with the fourth aspect to the fourth possible implementation, in the fifth possible implementation, the above-mentioned determination of the target plasma distribution required in the process chamber based on the current processing information includes: comparing the current processing information with preset processing information to determine whether there is a deviation between the current processing information and the preset processing information; if there is a deviation between the current processing information and the preset processing information, determining the target plasma distribution required in the process chamber based on the plasma distribution associated with the preset processing information. Specifically, the preset processing information may include preset plasma distributions corresponding to etching requirements, deposition requirements, and surface cleaning requirements, respectively. By comparing the current processing information with the preset processing information, if there is a deviation between the current processing information and the preset processing information, the preset plasma distribution can be determined as the target plasma distribution. This allows for subsequent adjustment of the variable capacitor in the RF matching unit to bring the plasma distribution in the process chamber closer to the target plasma distribution, thereby improving the accuracy of plasma distribution control and achieving complex process effects.

[0019] In conjunction with the fourth to fifth possible implementations, in the sixth possible implementation, determining the target current ratio between the first and second coils based on the target plasma distribution includes: calling a pre-established electromagnetic-plasma coupling model, outputting the coil current ratio configuration parameters corresponding to the target plasma distribution through simulation or table lookup, and using the coil current ratio configuration parameters as the target current ratio. It should be understood that the pre-established electromagnetic-plasma coupling model reflects a precise mapping between the target plasma distribution and the current ratio, enabling faster and more accurate establishment of the required plasma distribution state within the current process chamber, thereby significantly improving process efficiency.

[0020] In conjunction with the sixth possible implementation of the fourth aspect, in the seventh possible implementation, after adjusting the capacitance value of the first variable capacitor to achieve the target current ratio between the first coil and the second coil, the method further includes: real-time detection of the actual current ratio between the first coil and the second coil, and comparison with the target current ratio; if the deviation between the actual current ratio and the target current ratio exceeds a preset threshold, controlling the RF matching device to make the deviation between the actual current ratio of the first coil and the second coil and the target current ratio less than or equal to the target range. It should be understood that by real-time detection of the actual current ratio of the first coil and the second coil, and subsequently real-time adjustment of the actual current ratio of the first coil and the second coil to make the actual current ratio of the first coil and the second coil approach the target current ratio, current drift caused by factors such as RF source fluctuations, coil temperature rise leading to resistance changes, and electromagnetic interference can be effectively offset, ensuring a high degree of consistency between the actual magnetic field distribution and the required magnetic field distribution, thus improving the repeatability and stability of the process. Furthermore, in multi-zone magnetic field collaborative control scenarios, accurately maintaining the current ratio can avoid plasma distribution distortion caused by local magnetic field deviations, further ensuring process effectiveness and significantly improving the process yield in the mass production stage. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the plasma processing device provided in the embodiments of this application; Figure 2 This is a schematic diagram of the radio frequency coupling device provided in an embodiment of this application; Figure 3 This is a current characteristic diagram of the first and second coils provided in the embodiments of this application; Figure 4 This is another structural schematic diagram of the radio frequency coupling device provided in the embodiments of this application; Figure 5 This is another current characteristic diagram of the first and second coils provided in the embodiments of this application; Figure 6 This is another structural schematic diagram of the radio frequency coupling device provided in the embodiments of this application; Figure 7 This is another current characteristic diagram of the first and second coils provided in the embodiments of this application; Figure 8 This is another structural schematic diagram of the radio frequency coupling device provided in the embodiments of this application; Figure 9 This is a schematic flowchart of a plasma distribution adjustment method provided in an embodiment of this application.

[0022] Explanation of reference numerals in the attached figures: 1-Plasma processing equipment; 10 - Radio frequency coupling device; 20 - Process chamber; 30 - Electrostatic chuck; 40 - Gas supply unit; 50 - Gas nozzle; 60 - Medium window; 101 - Radio frequency source; 102 - First coil; 103 - Second coil; 104 - First variable capacitor; 105 - Third variable capacitor; 106 - Fourth variable capacitor; 107 - Second variable capacitor; 108 - Fixed capacitor; 109 - Fifth variable capacitor; 110 - First inductor; 111 - Second inductor; 112 - Third inductor; 113 - Sixth variable capacitor. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the described embodiments are merely some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0024] To facilitate understanding, the following brief explanations are provided for some of the terms: Particles: In wafer manufacturing, particles refer to tiny material particles, such as dust, droplets, and germs. They vary in size and can have a negative impact on the semiconductor manufacturing process.

[0025] Plasma, also known as electric plasma, is an ionized gaseous substance composed of positive and negative ions produced by the ionization of atoms and atomic groups after some electrons have been stripped away. It is a macroscopic electrically neutral ionized gas with a scale greater than the Debye length, and its motion is mainly governed by electromagnetic forces.

[0026] Etching: Transferring the photoresist pattern obtained by photolithography onto a thin film on the wafer surface. That is, using the covering and protective effect of the photoresist film, the thin film without photoresist protection is removed by chemical reaction or physical action to complete the pattern transfer.

[0027] Deposition: The formation of a solid thin film with specific functions (such as insulation, conductivity, masking, or protection) on the surface of a wafer (substrate) through physical or chemical methods.

[0028] Surface cleaning: A key process step that removes various contaminants from the wafer surface using physical or chemical methods to obtain a clean surface that meets process requirements.

[0029] In semiconductor device manufacturing, plasma plays a crucial role in processes such as etching, deposition, and surface cleaning. In chemical vapor deposition (CVD) and etching, the electron temperature within the plasma is extremely high (tens of thousands of degrees Celsius), but the overall gas temperature can be maintained at a relatively low level. This allows the CVD and etching reactions to proceed in a low-temperature environment, thus preserving the existing metal interconnects and doped structures of the workpiece. In surface cleaning processes, plasma is also used to remove particles, metal ions, organic matter, native oxide layers, and residues from previous processes from the wafer surface without damaging the wafer surface or underlying structure. Because plasma is generated by coupling energy into the process chamber via a radio frequency power supply, it is unevenly distributed within the chamber. Furthermore, plasma is a nonlinear system strongly coupled by multiple physical fields (electromagnetic field, flow field, temperature field, and chemical reaction field), and its behavior lies at the critical point between microscopic particle motion and macroscopic process results, making precise control of plasma density difficult.

[0030] Based on this, embodiments of this application provide a radio frequency matching device that can be applied to plasma processing equipment. The radio frequency matching device can adjust the ratio of the first coil to the second coil flowing through the plasma processing equipment to regulate the magnetic field distribution generated by the first and second coils, thereby controlling the plasma distribution within the process chamber. This optimizes the process effect, effectively improves the control accuracy of plasma density distribution, and has strong adaptability. The radio frequency matching device provided in this application embodiment will be illustrated below with reference to the accompanying drawings.

[0031] Example 1 See Figure 1 , Figure 1 This is a schematic diagram of the plasma processing device provided in an embodiment of this application. Figure 1 As shown, the plasma processing equipment 1 includes a radio frequency coupling device 10 and a process chamber 20. Here, the radio frequency coupling device 10 can be located outside the process chamber 20 and can be used to couple radio frequency energy into the process chamber 20 via electromagnetic induction, exciting and controlling the plasma distribution. An electrostatic chuck 30 can be located inside the process chamber 20, and the workpiece to be processed (such as a wafer) can be placed on the electrostatic chuck 30. During process steps (such as etching, deposition, surface cleaning, etc.), the gas supply unit 40 can inject reactive gas into the process chamber 20 through the gas nozzle 50. The radio frequency coupling device 10 can excite the reactive gas in the process chamber 20 into a plasma state to achieve various process effects. Please refer to [further details omitted]. Figure 2 , Figure 2 This is a schematic diagram of the structure of the radio frequency coupling device 10 provided in an embodiment of this application. Figure 2As shown, the radio frequency coupling device 10 may include a radio frequency source 101, a first coil 102, a second coil 103, and a radio frequency matching device. The radio frequency source 101, the first coil 102, and the second coil 103 can be connected in series to form a radio frequency current path. Here, the radio frequency source 101, the first coil 102, and the second coil 103 are connected in series and then connected to a ground terminal. The radio frequency matching device may include a first variable capacitor 104, which can be connected between the node (denoted as node a) between the first coil 102 and the second coil 103 and the ground terminal. The first variable capacitor 104 can be used to adjust the ratio of the radio frequency current generated by the radio frequency source 101 flowing through the first coil 102 and the second coil 103, thereby adjusting the magnetic field distribution generated by the first coil 102 and the second coil 103, and thus controlling the plasma distribution within the process chamber.

[0032] See Figure 2 Since the first variable capacitor 104 is connected between node a (between the first coil 102 and the second coil 103) and the ground terminal, the current flowing through the first coil 102 is split at node a. Specifically, a portion of the current flowing through the first coil 102 flows through the branch containing the second coil 103, while the other portion flows through the branch containing the first variable capacitor 104. The current relationship between the first coil 102, the second coil 103, and the first variable capacitor 104 can be seen in the following formula: = + (1) In formula (1), The current flowing through the first coil 102, The current flowing through the second coil 103, The current flowing through the first variable capacitor 104 is used. Further, the radio frequency current emitted by the radio frequency power supply flows sequentially through the first coil 102 and the second coil 103, generating a magnetic field around the first coil 102 and the second coil 103. This magnetic field passes through the dielectric window 60 and induces an electric field within the process chamber 20. The reactive gas within the process chamber 20 is ionized by collisions with electrons accelerated by the induced electric field, thereby generating plasma within the process chamber 20. It is worth noting that the greater the current flowing through the coils, the higher the magnetic field strength generated by the coils, and the stronger the induced electric field, resulting in a higher plasma density in that region. Based on this, when the capacitance value of the first variable capacitor 104 changes, the impedance of the branch containing the first variable capacitor 104 changes, thereby adjusting the ratio of the radio frequency current flowing through the first coil 102 and the second coil 103, and the plasma distribution follows accordingly. and The impedance changes with the change. For ease of description, the impedance on the branch where the second coil 103 is located is denoted as... The impedance of the branch containing the first variable capacitor 104 is denoted as... ,but and Please refer to the following formula: (2) (3) In formulas (2) and (3), This refers to the resistance component of the second coil 103. Here, ω represents the reactance component of the second coil 103, and ω is the radio frequency angular frequency. The inductance of the second coil 103 This is the reactance component of the first variable capacitor 104. This is the capacitance value of the first variable capacitor 104. Since the second coil 103 is connected in parallel with the first variable capacitor 104, therefore... and The relationship can be found in formula (4).

[0033] = (4) According to formulas (1) to (4), and The ratio can be found in the following formula: = +1= +1 (5) According to formula (5), It changes with the capacitance value of the first variable capacitor 104. When the frequency changes, the ratio of the radio frequency current flowing through the first coil 102 and the second coil 103 changes accordingly, causing the magnetic field distribution of the first coil 102 and the second coil 103 in the process chamber 20 to change, thereby realizing the control of the plasma distribution in the process chamber 20.

[0034] It should be understood that the radio frequency current generated by the radio frequency source 101 is shunted at node a after flowing through the first coil 102 and then flows through the second coil 103. The first variable capacitor 104 in the radio frequency matching unit can adjust the ratio of the radio frequency current flowing through the first coil 102 to the second coil 103, thereby changing the magnitude of the current flowing through the first coil 102 and the second coil 103, to adjust the magnetic field distribution generated by the first coil 102 and the second coil 103, thereby controlling the plasma distribution in the process chamber. It should also be understood that since the first coil 102 is not directly grounded, the end of the first coil 102 connected to node a maintains a high potential relative to ground, which is beneficial for the ignition of the process chamber 20. In contrast, the second coil 103 is directly grounded, and the end of the second coil 103 connected to the ground terminal has a zero potential relative to ground, eliminating the potential difference. This helps reduce abnormal arc discharge or sparking between the second coil 103 and the central inlet pipe of the process chamber 20, and reduces the risk of parasitic ignition of the gas nozzle. See also... Figure 3 , Figure 3 This is a current characteristic diagram of the first coil 102 and the second coil 103 provided in the embodiments of this application. For example... Figure 3 As shown, The current ratio is linearly related to the capacitance value of the first variable capacitor 104, where the horizontal axis represents the capacitance value of the first variable capacitor 104. Thus, in practical applications, the capacitance value of the first variable capacitor 104 can be directly adjusted for flexible regulation. The current ratio is adjusted to regulate plasma distribution, resulting in simple control and a fast response speed. It is worth mentioning that... The adjustment range when the current ratio of the first coil 102 and the second coil 103 currents are in phase is greater than that when they are in phase. The range of adjustment when the phase of the first coil 102 and the phase of the current in the second coil 103 are opposite makes it easier to achieve precise control of plasma distribution, thereby improving process capability.

[0035] In one feasible implementation, the RF matching unit may further include a second variable capacitor 107, which may be connected between the second coil 103 and the ground terminal. The second variable capacitor 107 may be used in conjunction with the first variable capacitor 104 to adjust the ratio of the RF current generated by the RF source 101 flowing through the first coil 102 and the second coil 103, so as to adjust the magnetic field distribution generated by the first coil 102 and the second coil 103, thereby controlling the plasma distribution in the process chamber.

[0036] See Figure 4 , Figure 4 This is another structural schematic diagram of the radio frequency coupling device 10 provided in the embodiments of this application. For example... Figure 4As shown, the branch containing the second coil 103 also includes a second variable capacitor 107. Here, one end of the second variable capacitor 107 is connected to the first coil 102, and the other end of the second variable capacitor 107 is connected to the ground terminal. At this time, the impedance of the branch containing the second coil 103 can be seen from the following formula (6), and the impedance of the branch containing the first variable capacitor 104 can be seen from the following formula (7): (6) (7) In formulas (6) and (7), This refers to the resistance component of the second coil 103. Here, ω represents the reactance component of the second coil 103, and ω is the radio frequency angular frequency. The inductance of the second coil 103 The capacitance value of the second variable capacitor 107. This is the reactance component of the first variable capacitor 104. Let be the capacitance value of the first variable capacitor 104. At this time, according to formula (5), when the capacitance value of at least one of the first variable capacitor 104 and the second variable capacitor 107 changes, The current ratio also changes, causing the magnetic field distribution of the first coil 102 and the second coil 103 within the process chamber 20 to change, thereby achieving control over the plasma distribution within the process chamber 20. It should also be understood that since the second variable capacitor 107 is connected between the second coil 103 and the ground terminal, neither the first coil 102 nor the second coil 103 is directly grounded. The end of the first coil 102 connected to node a and the end of the second coil 103 connected to the second variable capacitor 107 maintain a high potential relative to ground, which is beneficial for ignition in the process chamber 20, expanding the ignition window while reducing the risks of other abnormal arc discharges, sparking, or parasitic ignition. Furthermore, when the capacitance value of the first variable capacitor 104 changes, the potential of the end of the first coil 102 connected to node a changes accordingly; similarly, when the capacitance value of the second variable capacitor 107 changes, the potential of the end of the second coil 103 connected to the ground terminal changes accordingly. Therefore, the potentials of the end of the first coil 102 connected to node a and the end of the second coil 103 connected to the ground terminal can be adjusted according to process requirements. Additionally, see Figure 5 , Figure 5 This is another current characteristic diagram of the first coil 102 and the second coil 103 provided in the embodiments of this application. For example... Figure 5 As shown, when the phase of the current in the first coil 102 is in phase with the phase of the current in the second coil 103, and the capacitance value of the first variable capacitor 104 is 1500pF or 775pF, The current ratio increases as the capacitance of the second variable capacitor 107 increases. At this time, The current ratio is highly sensitive to the capacitance value of the second variable capacitor 107; that is, a small change in capacitance will cause a large change in the current ratio. When the capacitance value of the first variable capacitor 104 is 50pF, and the phase of the current in the first coil 102 and the phase of the current in the second coil 103 are in phase, The change in the current ratio is relatively slow at this time. The current ratio is highly sensitive to the capacitance value of the second variable capacitor 107 when the phases of the currents in the first coil 102 and the second coil 103 are out of phase. Based on this, the current ratio operating range can be selected more flexibly according to process requirements, and the current ratio can be combined with process requirements... At least one variable capacitor adjustment current ratio is selected based on the sensitivity of the capacitance value of the second variable capacitor 107 or the first variable capacitor 104.

[0037] In some feasible embodiments, the plasma processing apparatus may also include a fixed capacitor 108, such as Figure 6 As shown, the fixed capacitor 108 is connected between the second coil 103 and the ground terminal. At this time, the impedance of the branch containing the second coil 103 can be found using the following formula (8), and the impedance of the branch containing the first variable capacitor 104 can be found using the following formula: (8) (9) In formulas (8) and (9), This refers to the resistance component of the second coil 103. Here, ω represents the reactance component of the second coil 103, and ω is the radio frequency angular frequency. The inductance of the second coil 103 To fix the capacitance value of capacitor 108, This is the reactance component of the first variable capacitor 104. The capacitance value of the first variable capacitor 104.

[0038] It should also be understood that, since the first coil 102 is connected to the grounding terminal via the second coil 103 and the fixed capacitor 108, and the fixed capacitor 108 is connected between the second coil 103 and the grounding terminal, neither the first coil 102 nor the second coil 103 is directly grounded. The end of the first coil 102 connected to node a and the end of the second coil 103 connected to the fixed capacitor 108 both maintain a high potential relative to ground. This is beneficial for the ignition of the process chamber 20, expanding the ignition window while reducing the risks of other abnormal arc discharges or sparking, parasitic ignition, etc. Additionally, see... Figure 7 , Figure 7 This is another current characteristic diagram of the first coil 102 and the second coil 103 provided in the embodiments of this application. For example... Figure 7 As shown, The current ratio is linearly related to the capacitance value of the first variable capacitor 104. Therefore, the capacitance value of the first variable capacitor 104 can be directly adjusted according to the required plasma distribution within the process chamber 20 to regulate the plasma flow. The current ratio is high, control is simple, and the response speed is fast. Furthermore, when the phase of the current in the first coil 102 and the phase of the current in the second coil 103 are in phase, It has a wider adjustment range and makes it easier to achieve precise control of plasma distribution.

[0039] In some feasible implementations, when the diameters of the first coil 102 and the second coil 103 are different, the magnetic field distributions of the first coil 102 and the second coil 103 within the process chamber 20 are also different. For example, when the diameter of the first coil 102 is larger than the diameter of the second coil 103, the magnetic field generated by the first coil 102 is distributed in the edge region of the process chamber 20, while the magnetic field generated by the second coil 103 is distributed in the central region of the process chamber 20. Thus, the first coil 102 and the second coil 103 can excite plasma in the central and edge regions of the process chamber 20, forming two regions with different plasma densities radially within the process chamber 20. The plasma in each region is excited by the radio frequency energy of different coils. Therefore, when the capacitance value of the first variable capacitor 104 changes, the plasma density in the central and edge regions also changes accordingly. Specifically, when the ratio of the current in the first coil 102 to the current in the second coil 103 increases, the RF power deposition density in the edge region of the process chamber 20 increases, while the RF power deposition density in the central region decreases. This, in turn, increases the plasma density in the edge region of the process chamber 20 and decreases the plasma density in the central region. Thus, during the etching process, the etching rate and etching depth in the edge region increase. During the deposition process, the deposition rate in the edge region increases, resulting in a thicker edge film. During the surface cleaning process, the cleaning rate in the edge region increases, enhancing the ion bombardment capability and enabling the removal of reaction byproduct particles adsorbed on the inner wall of the process chamber 20.

[0040] Similarly, when the ratio of the current in the first coil 102 to the current in the second coil 103 decreases, the RF power deposition density in the central region of the process chamber 20 increases, while the RF power deposition density in the edge region decreases. This, in turn, increases the plasma density in the central region of the process chamber 20 and decreases the plasma density in the edge region. Thus, during the etching process, the etching rate and etching depth in the central region increase. During the deposition process, the deposition rate in the central region increases, resulting in a thicker central film. During the surface cleaning process, the cleaning rate in the central region increases, enhancing the ion bombardment capability, which can remove reaction byproduct particles adsorbed on the surface of the central region of the process chamber 20 and the components within the process chamber 20 (such as the gas nozzle 50, electrostatic chuck 30, edge rings, and other process kits).

[0041] In some feasible implementations, when the diameter of the first coil 102 is smaller than the diameter of the second coil 103, the magnetic field generated by the first coil 102 is distributed in the central region of the process chamber 20, and the magnetic field generated by the second coil 103 is distributed in the edge region of the process chamber 20. Therefore, when the capacitance value of the first variable capacitor 104 changes, the plasma density in the central and edge regions also changes accordingly. Specifically, when the ratio of the current in the first coil 102 to the current in the second coil 103 increases, the RF power deposition density in the central region of the process chamber 20 increases, and the RF power deposition density in the edge region decreases, thereby increasing the plasma density in the central region of the process chamber 20 and decreasing the plasma density in the edge region. Thus, during the etching process, the etching rate in the central region increases, and the etching depth increases. During the deposition process, the deposition rate in the central region increases, and the thickness of the central thin film is high. When performing the surface cleaning process, the cleaning rate of the central region is increased and the ion bombardment capability is enhanced, which can remove the reaction byproduct particles adsorbed on the surface of the central region of the process chamber 20 and the components (such as the gas nozzle 50, the electrostatic chuck 30, the edge ring, and other process kits) within the process chamber 20.

[0042] Similarly, when the ratio of the current in the first coil 102 to the current in the second coil 103 decreases, the RF power deposition density in the edge region of the process chamber 20 increases, while the RF power deposition density in the center region decreases. This, in turn, increases the plasma density in the edge region of the process chamber 20 and decreases the plasma density in the center region. Thus, during the etching process, the etching rate and etching depth in the edge region increase. During the deposition process, the deposition rate in the edge region increases, resulting in a thicker edge film. During the surface cleaning process, the cleaning rate in the edge region increases, enhancing ion bombardment capability and enabling the removal of reaction byproduct particles adsorbed on the inner wall of the process chamber 20.

[0043] In summary, by adjusting the ratio of radio frequency current flowing through the first coil 102 and the second coil 103, the plasma distribution within the process chamber 20 can be controlled, thereby satisfying different process effects.

[0044] In one feasible implementation, when the diameters of the first coil 102 and the second coil 103 are different, the first coil 102 and the second coil 103 can be coaxially nested and disposed on the dielectric window 60. This arrangement allows for independent power distribution; that is, by adjusting the proportion of radio frequency current flowing through the first coil 102 and the second coil 103, the power ratio of the first coil 102 and the second coil 103 can be adjusted to regulate the plasma density. Optionally, the first coil 102 and the second coil 103 can be located on planes at different heights, with one coil disposed on the dielectric window 60 and the other coil located on the periphery of the sidewall of the process chamber 20. This arrangement can control the ionization rate of the plasma, as well as the ion energy and radial uniformity. Optionally, one coil of the first coil 102 and the second coil 103 can be distributed along the dome arc surface at the top of the process chamber 20, and the other coil can be wound around the periphery of the cylindrical sidewall of the process chamber 20. This arrangement can generate an additional coupling field in the edge region, suitable for edge uniformity control of large-size wafers (such as 300mm or 450mm). It should be understood that the embodiments of this application do not impose restrictions on the diameter of the first coil 102 and the geometric position of the second coil 103, which can be determined according to the actual application scenario.

[0045] In one feasible implementation, such as Figure 2 As shown, the RF matching unit may further include a third variable capacitor 105 and a fourth variable capacitor 106. The first output terminal of the RF source 101 is connected to one end of the third variable capacitor 105, the second output terminal of the RF source 101 is connected to one end of the fourth variable capacitor 106, the other end of the fourth variable capacitor 106 is connected to ground, and the other end of the third variable capacitor 105 is connected to the first terminal of the first coil 102. Here, the third variable capacitor 105 and the fourth variable capacitor 106 are configured as variable capacitors. By adjusting the capacitance values ​​of the third variable capacitor 105 and the fourth variable capacitor 106, the output impedance of the RF source 101 and the input impedance of the load (such as the plasma in the process chamber 20, the first coil 102, the second coil 103, etc.) can be matched, ensuring that the RF source 101 can effectively transfer energy to the load to provide maximum power transfer and efficiency. For example, the third variable capacitor 105 and the fourth variable capacitor 106 can achieve a load impedance matching state of 50 ohms, at which point the reflected power is minimized, and the RF power can be transferred to the process chamber 20 with maximum efficiency.

[0046] In one feasible implementation, the RF matching unit may further include a first inductor 110, a second inductor 111, a third inductor 112, a third variable capacitor 105, a fourth variable capacitor 106, a fifth variable capacitor 109, and a sixth variable capacitor 113. See also Figure 8 , Figure 8 This is another structural schematic diagram of the radio frequency coupling device 10 provided in the embodiments of this application. For example... Figure 8 As shown, the RF source 101 is connected to one end of the fourth variable capacitor 106 and one end of the first inductor 110. The other end of the first inductor 110 is connected to one end of the fifth variable capacitor 109 and one end of the third variable capacitor 105. The other end of the fifth variable capacitor 109 is connected to one end of the second inductor 111. The other end of the third variable capacitor 105 is connected to one end of the third inductor 112. The other end of the third inductor 112 is connected to one end of the sixth variable capacitor 113 and the first coil 102. The other ends of the fourth variable capacitor 106, the first inductor 110, and the sixth variable capacitor 113 are connected to ground. Here, by adjusting the capacitance values ​​of the third variable capacitor 105, the fourth variable capacitor 106, the fifth variable capacitor 109, and the sixth variable capacitor 113, the output impedance of the RF power supply and the input impedance of the load can be matched, ensuring that the RF power supply can effectively transfer energy to the load to provide maximum power transfer and efficiency.

[0047] In one feasible implementation, the reaction gas can be an inert gas, an oxygen source, or a hydrogen source. Specifically, the reaction gas within the process chamber 20 primarily uses inert gas and hydrogen / oxygen sources. Using easily ionizable inert gas generates a large number of ions in a low-RF power environment. These ions gain energy through an electric field, thereby removing attached particulate byproducts through a physical bombardment effect, effectively improving the cleaning effect. Using hydrogen or oxygen source gases, after ionization, allows for corresponding chemical reactions with fluorine-containing and organic particles, further enhancing the cleaning effect. Furthermore, oxygen source plasma can protect the coating and electrostatic chuck 30, protecting the coating and process kit within the process chamber 20 while removing particulate byproducts.

[0048] In one feasible implementation, the plasma processing device 1 may further include a pressure regulating unit. This unit can reduce the gas pressure within the process chamber 20 to increase the mean molecular free path of the gas within the process chamber 20, thereby promoting plasma diffusion and ultimately cleaning the dead zones of the process kit within the process chamber 20. Optionally, the plasma processing device 1 may also include a controller. The controller may be composed of one or more of a microprocessor, microcontroller, programmable logic unit (PLU), field-programmable gate array (FPGA), application-specific integrated circuit (ASIC), digital signal processor (DSP), and digital logic chip; this embodiment does not limit this. The controller can establish a communication connection with the pressure regulating unit to obtain the gas pressure within the process chamber 20 and control the pressure regulating unit to adjust the gas pressure within the process chamber 20. For example, the controller can control the pressure regulating unit to adjust the gas pressure within the process chamber 20 to regulate the plasma dissociation and ionization degrees, thereby changing the component ratio of ions and free radicals in the plasma and adjusting the intensity ratio of chemical reactions and physical bombardment during the cleaning process. Here, increasing the proportion of physical bombardment during the cleaning process can effectively remove large particles, stubborn polymer residues, hard masks, or metal fragments. When dealing with fragile structures, sensitive materials, or requiring atomic-level smoothness, the proportion of chemical reactions during the cleaning process can be increased. It should be understood that different cleaning effects can be achieved by adjusting the air pressure within the process chamber 20.

[0049] In one feasible implementation, the gas supply unit 40 can adjust the gas ratio within the process chamber 20, thereby regulating the airflow distribution within the process chamber 20 to achieve different cleaning effects for specific areas. Here, the controller can establish a communication connection with the gas supply unit 40, obtain the gas ratio within the process chamber 20 based on the communication connection, and control the gas supply unit 40 to adjust the gas ratio within the process chamber 20. For example, the controller can control the gas supply unit 40 to increase the airflow ratio in the central region of the process chamber 20, thus concentrating the airflow on the process components within the process chamber 20 and enhancing the cleaning effect in the central region. When the controller controls the gas supply unit 40 to increase the airflow ratio in the edge regions of the process chamber 20, more airflow will flow from the inner wall of the process chamber 20 towards the central region, thereby improving the uniformity of cleaning in the edge regions.

[0050] In this embodiment, by shunting the current flowing through the first coil 102, one current can flow through the second coil 103 and the other through the first variable capacitor 104. In this way, the plasma distribution in the process chamber 20 can be controlled without changing the radio frequency power, thereby achieving different process effects.

[0051] Example 2 This application provides a plasma distribution adjustment method (hereinafter referred to as the method provided in this application embodiment for ease of description), which can be applied to the above-mentioned... Figures 1 to 8 The RF matching device shown in any of the illustrations can be applied to plasma processing equipment, which may include a process chamber, an RF matching device, a first coil, and a second coil. Here, the RF source, the first coil, and the second coil are connected in series and then connected to a ground terminal. The RF matching device may include a first variable capacitor connected between the node between the first and second coils and the ground terminal. In one feasible embodiment, the RF matching device, the first coil, the second coil, and the RF matching device can constitute an RF coupling device. The following will be combined with... Figure 9 The plasma distribution adjustment method provided in the embodiments of this application will be illustrated by example. Figure 9 This is a schematic flowchart of the plasma distribution adjustment method provided in an embodiment of this application. Figure 9 As shown, the method provided in this application embodiment includes the following steps: S701, Obtain the current processing information of the workpiece to be processed.

[0052] In one feasible implementation, the workpiece to be processed can be a mask or a wafer. The mask can cover areas of the wafer surface that do not need to be etched, thereby isolating the etching gas or plasma from the material to be etched. This ensures that specific areas are protected from etching or ion implantation, thus enabling the transfer of the etched pattern. By acquiring the current processing information of the mask, the plasma distribution within the process chamber can be adjusted as needed during subsequent etching processes, ensuring the accuracy of the etched pattern and improving etching precision. As the substrate for various semiconductor devices, from tiny transistors to complex integrated circuits, wafers require processing and manufacturing. Therefore, acquiring the current processing information of the wafer is beneficial for adjusting the plasma distribution within the process chamber as needed during subsequent processes, ensuring wafer manufacturing precision and performance.

[0053] In one feasible implementation, the current processing information may include at least one of the following: etching rate, film thickness uniformity, and edge profile morphology of the workpiece to be processed. It should be understood that the etching rate can be used for feedback control to adjust the etching rate in real time, thereby improving etching accuracy. Film thickness uniformity can reflect whether there are problems such as uneven airflow distribution, uneven plasma density, or abnormal electrostatic chuck temperature distribution within the process chamber. Edge profile morphology refers to the shape, angle, undercut condition, and physical morphology of the edge chamfer at the microstructural level after etching, and can be used to determine whether a cleaning process needs to be triggered. Optionally, the current processing information may include the real-time plasma distribution within the process chamber. The real-time plasma distribution within the process chamber can be acquired in real time through one or more of the following methods: optical emission spectroscopy, interferometry, and plasma impedance monitoring; this application does not limit this. It should be understood that the real-time plasma distribution can provide feedback on the current plasma distribution within the process chamber, thereby determining whether the current plasma distribution within the process chamber needs to be adjusted. Optionally, the current processing information may also include process requirements, which may include etching requirements, deposition requirements, or surface cleaning requirements, as well as the target plasma distribution corresponding to each of these requirements. Here, the process requirements determine the energy state, chemical properties, and physical directionality of the plasma. By using the target plasma distributions corresponding to the etching, deposition, and surface cleaning requirements, the plasma distribution within the current process chamber can be adjusted in real time to ensure that the plasma distribution within the current process chamber meets the process requirements. It should be understood that the embodiments of this application do not limit the current processing information; the specific details can be determined according to the actual application scenario.

[0054] S702, based on the current processing information, determines the target plasma distribution required within the process chamber.

[0055] In one feasible implementation, the current processing information is compared with preset processing information to determine whether there is a deviation between the two. If there is a deviation, the target plasma distribution required in the process chamber is determined based on the plasma distribution associated with the preset processing information.

[0056] In practice, the preset processing information can include preset plasma distributions corresponding to etching requirements, deposition requirements, and surface cleaning requirements, respectively. By comparing the current processing information with the preset processing information, if there is a deviation between the two, the preset plasma distribution can be determined as the target plasma distribution. This allows for subsequent adjustment of the variable capacitor in the RF matching unit to bring the plasma distribution within the process chamber closer to the target plasma distribution, thereby improving the accuracy of plasma distribution control and achieving complex process effects.

[0057] S703, based on the target plasma distribution, determine the target current ratio between the first coil and the second coil.

[0058] In one feasible implementation, the required magnetic field distribution within the process chamber is obtained based on the target plasma distribution. Further, based on the required magnetic field distribution, the geometric positions of the first and second coils, and their electromagnetic coupling characteristics, the target current ratio of the first and second coils corresponding to the required magnetic field distribution is determined. Specifically, when the diameters of the first and second coils are different, they can be coaxially nested and positioned on the dielectric window. This arrangement allows for independent power distribution; that is, by adjusting the proportion of radio frequency current flowing through the first and second coils, the power ratio of the first and second coils can be adjusted to regulate the plasma density. Optionally, the first and second coils can be located on planes at different heights, with one coil positioned on the dielectric window and the other located on the outer periphery of the process chamber sidewall. This arrangement can control the plasma ionization rate, as well as ion energy and radial uniformity. Optionally, one of the first and second coils can be distributed along the dome-shaped arc surface at the top of the process chamber, while the other coil can be wound around the cylindrical sidewall of the process chamber. This arrangement can generate additional coupling fields in the edge region, suitable for edge uniformity control of large-size wafers (such as 300mm or 450mm). It should be understood that the embodiments of this application do not limit the diameter of the first coil and the geometric position of the second coil, which can be determined according to the actual application scenario.

[0059] It should be understood that by inverting the target plasma distribution into the required magnetic field distribution within the process chamber, precise control over the plasma distribution pattern is achieved, effectively improving the yield and consistency of the workpieces to be processed. Simultaneously, it can adapt to the differentiated plasma distribution requirements of various processes, enhancing the flexibility of process development.

[0060] In one feasible implementation, a pre-established electromagnetic-plasma coupling model is invoked, and the coil current ratio configuration parameters corresponding to the target plasma distribution are output through simulation or table lookup, with these parameters serving as the target current ratio. It should be noted that the electromagnetic-plasma coupling model can be used to describe how a magnetic field excites and sustains plasma within the process chamber, and how the plasma, in turn, affects the distribution of the magnetic field. The electromagnetic-plasma coupling model can be constructed based on data such as the geometry of the plasma processing device, material properties, radio frequency, and the type and pressure of the reactant gases. It can also be constructed by combining the plasma distribution within the process chamber with the spatial distribution characteristics of different current ratios. It should be understood that the embodiments of this application do not limit the construction method of the electromagnetic-plasma coupling model. Therefore, the pre-established electromagnetic-plasma coupling model reflects a precise mapping between the target plasma distribution and the current ratio, enabling faster and more accurate establishment of the required plasma distribution state within the current process chamber, thereby significantly improving the process effect.

[0061] S704, based on the target current ratio, adjusts the capacitance value of the first variable capacitor so that the current ratio of the first coil to the second coil reaches the target current ratio, thereby controlling the plasma distribution in the process chamber.

[0062] In specific implementation, combined with Figures 2 to 8 By adjusting the capacitance value of the variable capacitor (such as at least one of the first and second variable capacitors) in the RF matching unit, the ratio of RF current flowing through the first coil to the second coil can be precisely allocated, thereby precisely controlling the current ratio of the current flowing through the first coil to the current flowing through the second coil, and thus achieving the regulation of plasma distribution in the process chamber. This can effectively improve the process effect and meet the differences in plasma requirements of different processes.

[0063] In one feasible implementation, after adjusting the capacitance value of the first variable capacitor to achieve a target current ratio between the first and second coils, the actual current ratio between the first and second coils can be detected in real time and compared with the target current ratio. If the deviation between the actual current ratio and the target current ratio exceeds a preset threshold, the RF matching unit is controlled to ensure that the deviation between the actual current ratio of the first and second coils and the target current ratio is less than or equal to a target range. The target range can be preset.

[0064] It should be understood that by real-time detection and adjustment of the actual current ratio of the first and second coils to bring it closer to the target current ratio, current drift caused by factors such as RF source fluctuations, coil temperature rise leading to resistance changes, and electromagnetic interference can be effectively offset. This ensures a high degree of consistency between the actual and required magnetic field distribution, improving the repeatability and stability of the process. Furthermore, in multi-zone magnetic field collaborative control scenarios, precisely maintaining the current ratio can avoid plasma distribution distortion caused by local magnetic field deviations, further guaranteeing process effectiveness and significantly improving process yield in mass production.

[0065] It is understandable that by adding a first variable capacitor between the node between the first coil and the second coil and the ground terminal, the plasma distribution in the process chamber can be changed by adjusting the capacitance value of the first variable capacitor without changing the radio frequency power emitted by the radio frequency source. This allows for flexible control of the plasma distribution, meets the differentiated requirements of different processes for plasma distribution, and optimizes the process effect.

[0066] Each of the above modules or units can be implemented through software, hardware, or a combination of both. For example, [as a preferred scenario] modules A, B, and C can all be implemented based on software.

[0067] In this application, "implemented through software" means that the processor reads and executes program instructions stored in memory to implement the functions corresponding to the aforementioned modules or units. Here, the processor refers to a processing circuit capable of executing program instructions, including but not limited to at least one of the following: a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), a microcontroller unit (MCU), or an artificial intelligence processor, etc., and other processing circuits capable of running program instructions. In other embodiments, the processor may also include circuits with other processing functions (such as hardware circuits for hardware acceleration, bus and interface circuits, etc.). The processor can be presented as an integrated chip, for example, as an integrated chip whose processing function only includes executing software instructions, or it can also be presented as a SoC (system on a chip), that is, on a single chip, in addition to the processing circuit capable of running program instructions (usually referred to as the "core"), it also includes other hardware circuits for implementing specific functions (of course, these hardware circuits can also be implemented separately based on ASIC or FPGA). Correspondingly, the processing functions, in addition to executing software instructions, may also include various hardware acceleration functions (such as AI calculation, encoding / decoding, compression / decompression, etc.).

[0068] In this application, "implemented in hardware" means that the functions of the above-mentioned modules or units are implemented through hardware processing circuits that do not have program instruction processing capabilities. These hardware processing circuits can be composed of discrete hardware components or integrated circuits. To reduce power consumption and size, integrated circuits are typically used. Hardware processing circuits can include ASICs (application-specific integrated circuits) or PLDs (programmable logic devices); PLDs can include FPGAs (field-programmable gate arrays), CPLDs (complex programmable logic devices), and so on. These hardware processing circuits can be a single packaged semiconductor chip (e.g., packaged as an ASIC); or they can be integrated with other circuits (e.g., CPUs, DSPs) and packaged into a single semiconductor chip. For example, multiple hardware circuits and a CPU can be formed on a silicon substrate and packaged into a single chip; this type of chip is also called a SoC. Alternatively, circuits for implementing FPGA functions and a CPU can be formed on a silicon substrate and encapsulated into a single chip; this type of chip is also called a SoPC (system on a programmable chip).

[0069] It should be noted that when this application is implemented through software, hardware, or a combination of both, different software or hardware can be used, and it is not limited to using only one type of software or hardware. For example, one module or unit can be implemented using a CPU, while another module or unit can be implemented using a DSP. Similarly, when implemented using hardware, one module or unit can be implemented using an ASIC, while another module or unit can be implemented using an FPGA. Of course, it is not limited to using the same software (e.g., all through a CPU) or the same hardware (e.g., all through an ASIC) to implement some or all modules or units. Furthermore, those skilled in the art will understand that software is generally more flexible but less performant than hardware, while hardware is the opposite. Therefore, those skilled in the art can choose software, hardware, or a combination of both based on actual needs.

[0070] The foregoing preferred embodiments have further illustrated the objectives, technical solutions, and advantages of the present invention. It should be understood that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0071] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. The terms “first,” “second,” etc., used in this application are for distinguishing purposes only and should not be construed as indicating or implying relative importance or order. The term “multiple” used in this application means at least two, i.e., two or more. The term “comprising,” and any variations thereof, in the specification, claims, and drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or device that includes a series of steps or modules is not limited to the listed steps or modules but may optionally include steps or modules not listed, or may optionally include other steps or modules inherent to such processes, methods, apparatus, products, or devices. Any embodiment or design described as “exemplary” or “for example” in the embodiments of this application should not be construed as preferred or advantageous over other embodiments or designs. Specifically, the use of words such as “exemplary” or “for example” is intended to present the relevant concepts in a specific manner. Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0072] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, any equivalent variations made in accordance with the claims of this application shall still fall within the scope of this application.

Claims

1. A radio frequency matching device, applied to a plasma processing equipment, the plasma processing equipment comprising a process chamber, a radio frequency source, a first coil, and a second coil, wherein the radio frequency source, the first coil, and the second coil are connected in series and then connected to a ground terminal, characterized in that, The radio frequency matching unit includes: A first variable capacitor is connected between the node between the first coil and the second coil and the ground terminal; The first variable capacitor is used to adjust the ratio of the radio frequency current generated by the radio frequency source flowing through the first coil and the second coil, so as to adjust the magnetic field distribution generated by the first coil and the second coil, thereby regulating the plasma distribution in the process chamber.

2. The radio frequency matching device according to claim 1, characterized in that, The radio frequency matching unit also includes: The second variable capacitor is connected between the second coil and the ground terminal. The second variable capacitor is used to work with the first variable capacitor to adjust the ratio of the radio frequency current generated by the radio frequency source flowing through the first coil and the second coil, so as to adjust the magnetic field distribution generated by the first coil and the second coil, thereby controlling the plasma distribution in the process chamber.

3. A radio frequency coupling device, characterized in that, include: Radio frequency source; The first coil and the second coil are connected in series to form an RF current path; And the radio frequency matching unit as described in claim 1 or 2; The first variable capacitor of the radio frequency matching device is connected between the node between the first coil and the second coil and the ground terminal. It is used to adjust the ratio of the radio frequency current generated by the radio frequency source flowing through the first coil and the second coil by adjusting the capacitance value of the first variable capacitor, thereby controlling the plasma distribution.

4. The radio frequency coupling device according to claim 3, characterized in that, The plasma processing equipment also includes a fixed capacitor connected between the second coil and the grounding terminal.

5. A plasma processing device, characterized in that, include: Process chambers; The radio frequency coupling device as described in claim 4 is disposed outside the process chamber and is used to couple radio frequency energy into the process chamber through electromagnetic induction to excite and regulate plasma distribution.

6. A plasma distribution adjustment method applied to a plasma processing device, the plasma processing device comprising a process chamber, a radio frequency matching unit, a first coil, and a second coil, the radio frequency matching unit comprising a first variable capacitor connected between a node between the first coil and the second coil and a ground terminal, characterized in that, The method includes: Obtain the current processing information of the workpiece to be processed; Based on the current processing information, the target plasma distribution required within the process chamber is determined; Based on the target plasma distribution, determine the target current ratio between the first coil and the second coil; Based on the target current ratio, the capacitance value of the first variable capacitor is adjusted so that the current ratio between the first coil and the second coil reaches the target current ratio, thereby regulating the plasma distribution in the process chamber.

7. The method according to claim 6, characterized in that, Determining the target current ratio between the first coil and the second coil based on the target plasma distribution includes: Based on the target plasma distribution, the required magnetic field distribution within the process chamber is obtained; Based on the required magnetic field distribution, the geometric positions of the first coil and the second coil, and their electromagnetic coupling characteristics, the target current ratio of the first coil and the second coil corresponding to the required magnetic field distribution is determined.

8. The method according to claim 6 or 7, characterized in that, The current processing information includes at least one of the following: etching rate, film thickness uniformity, and edge contour morphology of the workpiece to be processed.

9. The method according to any one of claims 6 to 8, characterized in that, The current processing information includes the real-time plasma distribution within the process chamber.

10. The method according to any one of claims 6 to 9, characterized in that, Determining the required target plasma distribution within the process chamber based on the current processing information includes: The current processing information is compared with the preset processing information to determine whether there is a deviation between the current processing information and the preset processing information; If there is a deviation between the current processing information and the preset processing information, the target plasma distribution required in the process chamber is determined based on the plasma distribution associated with the preset processing information.

11. The method according to any one of claims 6 to 10, characterized in that, Determining the target current ratio between the first coil and the second coil based on the target plasma distribution includes: The pre-established electromagnetic-plasma coupling model is invoked, and the coil current ratio configuration parameters corresponding to the target plasma distribution are output through simulation or table lookup, and the coil current ratio configuration parameters are used as the target current ratio.

12. The method according to any one of claims 6 to 11, characterized in that, After adjusting the capacitance value of the first variable capacitor according to the target current ratio so that the current ratio of the first coil to the second coil reaches the target current ratio, the method further includes: The actual current ratio of the first coil and the second coil is detected in real time and compared with the target current ratio. If the deviation between the actual current ratio and the target current ratio exceeds a preset threshold, the radio frequency matching device is controlled to make the deviation between the actual current ratio of the first coil and the second coil and the target current ratio less than or equal to the target range.

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