Radio frequency power supply output power calibration method and device, and semiconductor process method

Abstract

The invention provides a radio frequency power supply output power calibration method and device and a semiconductor process method, and the method comprises the steps: obtaining a first residual index, and comparing the first residual index with a reference etching stability index, thereby obtaining a first comparison index; and determining to adopt a residue calibration strategy or a uniform calibration strategy according to a comparison result of the first comparison index and a first threshold value. The residue calibration strategy preferentially adjusts the first lower radio frequency index and then calibrates the first upper radio frequency index; and the uniform calibration strategy firstly adjusts the second upper radio frequency index and then calibrates the second lower radio frequency index, so that the technical problems in the prior art that different stages of a residue retention scene cannot be quickly identified and the method for cooperatively calibrating the output power of the upper and lower radio frequency power supplies aiming at the different stages cannot be solved. The technical effects of improving the adaptability and flexibility of the etching process, improving the predictability of the etching process and adapting to various complex etching environments are achieved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor devices, and in particular to a method and device for calibrating the output power of a radio frequency power supply, and a semiconductor process method. Background Art

[0002] RF power is widely used in plasma etching equipment in the field of semiconductor manufacturing. In plasma etching equipment, there will be residues from the previous batch. In this mass production scenario, since the residues from the previous batch will affect the etching efficiency and etching uniformity of the next batch, it is necessary to quickly calibrate the output power of the RF power supply to adapt to the residue retention scenario. In particular, the residues from the previous batch will cause the initial conditions of the etching process of this batch to be unstable. Especially at the beginning of etching, the residues will require additional energy to calibrate removal or disposal, which will cause inconsistency between the initial stage and the subsequent stages of the etching process.

[0003] There are several methods and devices for calibrating the output power of a radio frequency power supply in the prior art.

[0004] The first one is that the current solution uses the hardware calibration of the phase-locked cable to calibrate the output power of the RF power supply. Specifically: the existing plasma equipment using RF power supply, such as Figure 1As shown, it includes a process chamber 13, an upper RF power supply 1 and a lower RF power supply 5, wherein a base 10 (for example, an electrostatic chuck) for carrying a wafer 9 is provided in the process chamber 13, and the lower RF power supply 5 is electrically connected to the base 10 through a lower matcher 4, so as to load bias power to the base 10. In addition, a dielectric window 8 is provided at the top of the process chamber 13, and an upper electrode is provided above the dielectric window 8, the upper electrode includes an outer coil 6 and an inner coil 7 of an inductive coupling coil, both of which are electrically connected to a current distribution unit 3, and the upper RF power supply 1 is electrically connected to the current distribution unit 3 through an upper matcher 2, so as to load RF power to the outer coil 6 and the inner coil 7 through the matcher 2 and the current distribution unit 3, and the RF energy is coupled to the process chamber 13 through the dielectric window 8. In addition, a nozzle 12 is also provided on the dielectric window 8, so as to introduce process gas into the process chamber 13. The above-mentioned RF energy can excite the process gas to generate plasma 11. The most important thing in the prior art is that it also includes a phase-locked cable 14, whose two ends are electrically connected to the upper RF power supply 1 and the lower RF power supply 5, respectively. In this case, one of the upper RF power supply 1 and the lower RF power supply 5 is usually defined as the master power supply (Master), and the other is defined as the slave power supply (Slave). By adjusting the phase difference of the output waveforms of the upper RF power supply 1 and the lower RF power supply 5, that is, the common excitation (Common Exciter, CEX) phase-locking angle, the coupling phase difference between the upper electrode and the lower electrode of the process chamber 13 on the surface of the wafer 9 can be adjusted, thereby affecting the ion energy and sheath potential above the wafer 9, and then changing the etching rate and Map distribution of the wafer 9. In other words, the change of the CEX phase-locking angle can directly affect the etching rate (ER, Etch Rate) and Map distribution. The following problem with this solution is that the RF output power is calibrated using a phase-locked cable. Due to the hardware limitations of the phase-locked cable, the RF output power cannot be calibrated quickly, flexibly and accurately to deal with the residue retention scenario. Specifically, due to the hardware limitations of the phase-locked cable, the hardware response speed is limited. The design of the phase-locked cable is optimized for stability rather than speed, which means that it does not respond quickly enough when dealing with rapidly changing dynamic conditions. The residue scenario in the semiconductor manufacturing process requires rapid power adjustment to ensure the efficiency and uniformity of the etching process, and the physical and electrical characteristics of the phase-locked cable cannot support such rapid changes. In addition, due to the inherent physical properties of the phase-locked cable, such as inductance, capacitance and resistance, the quality and accuracy of its transmitted signal will be affected. When the RF power output needs to be precisely adjusted to deal with the impact of the previous batch of residues on the current etching process, these characteristics will result in inaccurate adjustments and inability to achieve the ideal etching effect.

[0005] The second method is to use a large network model to calibrate or adjust the output power of the upper RF power supply and the lower RF power supply based on the plasma density at the specified position of each chamber near the semiconductor device. This solution is applied to conventional etching scenarios, but for etching scenarios with residues, the problem is that the etching scenario of the residues cannot be identified by simply detecting or quantifying the conventional indicator of plasma density. It is necessary to combine the etching rate and the rate of change of plasma density in the residue scenario. Because the residue scenario involves the initial stage and subsequent stage of the residue etching process, the time dimension needs to be considered. The simple quantitative evaluation of plasma density cannot accurately identify the residue etching scenario and the non-residue etching scenario, and it is even more impossible to match different RF output power control strategies based on the residue etching scenario and the non-residue etching scenario. In addition, in this technical solution, the upper RF output power and the lower RF output power are respectively for two large models, and the upper RF output power and the lower RF output power are not synergistically coupled, which cannot meet the requirements of residue removal and energy demand as well as system response and adjustment flexibility, especially the residues require additional energy to be removed or rendered harmless. The power output between the upper RF and the lower RF is not effectively coordinated, and insufficient energy can be provided to process the residues at the beginning stage, thus affecting the consistency and quality of the etching process and failing to meet the residue removal and energy requirements; and when the conditions in the reaction chamber change due to the residues, the rapid and coordinated response of the upper RF and the lower RF is very important. If this response is slow or uncoordinated, it will be difficult to quickly adapt to production variables, thus affecting the quality of the entire batch of products, and failing to meet the needs of system response and adjustment flexibility.

[0006] In summary, how to provide a method for quickly identifying the different stages of the residue retention scenario in semiconductor etching and collaboratively calibrating the output power of the upper and lower RF power supplies for the different stages has become a technical problem that needs to be urgently solved in this field. Summary of the invention

[0007] The embodiments of the present invention provide a method and device for calibrating the output power of an RF power supply, and a semiconductor process method, which solve the technical problem in the prior art that the different stages of the residue retention scenario and the method for collaboratively calibrating the output power of the upper and lower RF power supplies at the different stages cannot be quickly identified, and the different stages of the residue retention scenario can be accurately identified and the output power of the upper and lower RF power supplies can be collaboratively calibrated at the different stages, achieving the technical effect of improving the adaptability and flexibility of the etching process, enhancing the predictability of the etching process, and adapting to various complex etching environments.

[0008] According to one aspect of an embodiment of the present invention, a method for calibrating the output power of an RF power supply is provided, comprising: obtaining a first residual index, the first residual index being calculated based on a first etching rate and a first plasma density change rate, the first etching rate and the first plasma density change rate being both obtained within a first time T1 in a semiconductor etching region, wherein the first residual index is positively correlated with the first plasma density change rate and negatively correlated with the first etching rate; obtaining a reference etching stability index, the reference etching stability index being calculated based on a reference etching rate and a reference plasma density change rate, the reference etching rate and the reference plasma density change rate being both obtained within a first time T1 in a semiconductor etching region; obtaining a reference etching stability index based on the first residual index and the reference etching stability index, The quasi-etching stability index obtains a first comparison index, which is the first residual index divided by the benchmark etching stability index; the first comparison index is compared with the first threshold to obtain a comparison result; wherein, if the comparison result meets the first comparison range, a residue calibration strategy is executed, and the residue calibration strategy includes: according to the comparison result, first calibrating the first lower RF index and then calibrating the first upper RF index, and the first lower RF index and the first upper RF index both include the RF power supply output power; if the comparison result meets the second comparison range, a uniform calibration strategy is executed, and the uniform calibration strategy includes: according to the comparison result, first calibrating the second upper RF index and then calibrating the second lower RF index, and the second lower RF index and the second upper RF index both include the RF power supply output power.

[0009] According to one aspect of an embodiment of the present invention, a radio frequency power supply output power calibration device is provided, which is used to implement a radio frequency power supply output power calibration method, including: a first residual index acquisition unit, which is used to acquire a first residual index, and the first residual index is calculated based on a first etching rate and a first plasma density change rate, and the first etching rate and the first plasma density change rate are both acquired within a first time T1 in a semiconductor etching region, wherein the first residual index is positively correlated with the first plasma density change rate and negatively correlated with the first etching rate; a reference etching stability index acquisition unit, which is used to acquire a reference etching stability index, and the reference etching stability index is calculated based on a reference etching rate and a reference plasma density change rate, and the reference etching rate and the reference plasma density change rate are both acquired within the first time T1 in the semiconductor etching region; a first comparison index A determination unit is used to obtain a first comparison index according to a first residual index and a benchmark etching stability index, wherein the first comparison index is the first residual index divided by the benchmark etching stability index; a comparison unit is used to compare the first comparison index with a first threshold value to obtain a comparison result; an execution residue calibration unit is used to execute a residue calibration strategy if the comparison result satisfies a first comparison range, wherein the residue calibration strategy includes: calibrating the first lower RF index first and then calibrating the first upper RF index according to the comparison result, wherein the first lower RF index and the first upper RF index both include RF power supply output power; a uniform calibration unit is used to execute a uniform calibration strategy if the comparison result satisfies a second comparison range, wherein the uniform calibration strategy includes: calibrating the second upper RF index first and then calibrating the second lower RF index according to the comparison result, wherein the second lower RF index and the second upper RF index both include RF power supply output power.

[0010] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects:

[0011] A method and device for calibrating the output power of a radio frequency power supply and a semiconductor process method are proposed, including: first, obtaining a first residual index, the first residual index is calculated based on a first etching rate and a first plasma density change rate, the first etching rate and the first plasma density change rate are both obtained within a first time T1 of a semiconductor etching region, wherein the first residual index is positively correlated with the first plasma density change rate and negatively correlated with the first etching rate; obtaining a reference etching stability index, the reference etching stability index is calculated based on a reference etching rate and a reference plasma density change rate, the reference etching rate and the reference plasma density change rate are both obtained within a first time T1 of a semiconductor etching region; obtaining a first comparison index based on the first residual index and the reference etching stability index, the first comparison index is the first residual index divided by the reference etching stability index; comparing the first comparison index with the first threshold value to obtain a comparison result. By real-time monitoring of the first residual index, i.e., a comprehensive index of etching rate and plasma density change rate, the technical solution can quickly distinguish the influence stage of the residue, i.e., from the unstable stage at the beginning of etching to the subsequent stable stage. This rapid identification capability allows the RF power adjustment strategy to be more precisely targeted at the specific needs of the current stage, thereby improving the efficiency and effectiveness of the entire etching process. It also improves the predictability of the etching process. By real-time monitoring and automatic adjustment of the RF power supply, this solution provides a method to make the etching process more controllable and predictable. This not only improves the convenience of operation, but also ensures that technicians can make quick adjustments when necessary to adapt to immediate changes on the production line.

[0012] Secondly, if the comparison result satisfies the first comparison range, the residue calibration strategy is executed, and the residue calibration strategy includes: first calibrating the first lower RF index and then calibrating the first upper RF index according to the comparison result, and the first lower RF index and the first upper RF index both include the RF power supply output power. After confirming the specific stage of the residue influence, this scheme first adjusts the lower RF power supply to stabilize the base potential, and then adjusts the upper RF power supply to optimize plasma generation to achieve the best etching effect. This collaborative calibration takes into account the mutual influence of the upper and lower RF power supplies at different etching stages, thereby ensuring the maximum uniformity and efficiency of the etching process. The technical effects of adopting the residue calibration strategy are: First, strong pertinence: at the beginning of etching, due to the presence of residues, stronger RF indicators are required to remove the residues and stabilize the etching environment. The reason for adjusting the lower RF power supply index first is that it is directly connected to the base in contact with the wafer, and the bias on the wafer can be quickly adjusted to quickly process the residues, thereby improving the etching uniformity and efficiency. Second, quick response: after quickly adjusting the lower RF power supply, the adjustment of the upper RF power supply index can more finely control the density and energy distribution of the plasma and optimize the overall etching process. And, if the comparison result meets the second comparison range, a uniform calibration strategy is executed, and the uniform calibration strategy includes: according to the comparison result, first calibrate the second upper RF index and then calibrate the second lower RF index, and the second lower RF index and the second upper RF index both include the RF power supply output power. The technical effects of adopting a uniform calibration strategy are: First, maintain process uniformity: after the etching process reaches a relatively stable state, the uniform calibration strategy can uniformly control the plasma state in the entire cavity by first adjusting the upper RF power supply, and then finely adjust the wafer contact potential through the lower RF power supply to maintain the etching depth and uniformity. Second, improve etching quality: by optimizing the global distribution of plasma and locally adjusting the wafer potential, over-etching and under-etching can be reduced, and the product yield can be improved. Furthermore, the residue calibration strategy and the uniformity calibration strategy also have significant effects in overall synergy: First, dynamic identification and rapid response: By real-time monitoring of the etching rate and the rate of change of the plasma density, the presence of residues and their specific impact on the etching process can be quickly identified. The real-time identification capability allows the adjustment strategy of the RF power supply output indicators to quickly adapt to changes in the etching process, especially the transition from the residue treatment stage to the stable etching stage. This rapid response mechanism ensures that immediate action is taken when changes in etching conditions are detected, reducing etching quality problems caused by delayed adjustments. Second, coordinated adjustment of the upper and lower RF power supplies: In the residue removal stage, the strategy first adjusts the lower RF power supply to stabilize the potential of the wafer base and effectively treat the residues, and then adjusts the upper RF power supply to optimize the plasma conditions to achieve rapid and effective residue removal.When the etching process reaches a more stable state, the plasma environment of the entire chamber is adjusted by first optimizing the upper RF power supply, and then fine-tuning is performed through the lower RF power supply to maintain the etching depth and uniformity. This collaborative adjustment strategy ensures the optimal distribution of RF energy at each stage. Third, enhance the uniformity and quality of the etching process: The collaborative calibration strategy not only provides sufficient energy for processing residues in the initial stage through orderly adjustment of the upper and lower RF power supplies, but also ensures the uniformity and repeatability of the process when the etching process enters a stable stage. Each etching stage can obtain the most suitable RF power setting, thereby maximizing etching efficiency and product quality and reducing the defective rate.

[0013] In summary, the RF power output power calibration method aims to optimize the adjustment of RF indicators in the semiconductor etching process, by obtaining a first residual indicator and comparing it with a reference etching stability indicator to obtain a first comparison indicator. According to the comparison result of the first comparison indicator and the first threshold, it is decided to adopt a residue calibration strategy or a uniform calibration strategy. The residue calibration strategy prioritizes adjusting the first lower RF indicator and then calibrating the first upper RF indicator; while the uniform calibration strategy first adjusts the second upper RF indicator and then calibrates the second lower RF indicator. The residue calibration strategy is aimed at large deviations, and prioritizes adjusting the lower RF power supply and then adjusting the upper RF power supply; while the uniform calibration strategy is suitable for small deviations, and the upper RF power supply is adjusted first to ensure the consistency of the etching process. Both strategies realize the mutual coordinated calibration of the upper and lower RF indicators. In the residue retention scenario, rapid identification is guaranteed and the upper and lower RF power supplies are coordinated and calibrated for the different stages, ensuring the calibration accuracy, solving the technical problems in the prior art that the different stages of the residue retention scenario and the method for coordinating the output power of the upper and lower RF power supplies for the different stages cannot be quickly identified, and the technical effects of improving the adaptability and flexibility of the etching process, improving the predictability of the etching process, and adapting to various complex etching environments are achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments of the present invention are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 It is a structural schematic diagram of a radio frequency power supply output power calibration device in a semiconductor process method in the prior art;

[0016] Figure 2 A schematic diagram of the structure of a radio frequency power supply output power calibration device in a semiconductor process method according to an embodiment of the present invention;

[0017] Figure 3 A flow chart of a method for calibrating the output power of a radio frequency power supply provided by one embodiment of the present invention;

[0018] Figure 4 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by another embodiment of the present invention;

[0019] Figure 5 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by another embodiment of the present invention;

[0020] Figure 6 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by another embodiment of the present invention;

[0021] Figure 7 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by another embodiment of the present invention;

[0022] Figure 8 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by another embodiment of the present invention;

[0023] Fig. 9 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be described below in conjunction with the accompanying drawings in the embodiments of the present invention. In the description of the present invention, terms such as "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance or sequence.

[0025] The embodiment of the present invention aims to optimize the adjustment of the radio frequency index in the semiconductor etching process, by obtaining a first residual index and comparing it with a reference etching stability index to obtain a first comparison index. According to the comparison result of the first comparison index and the first threshold, it is decided to adopt a residue calibration strategy or a uniform calibration strategy. The residue calibration strategy prioritizes adjusting the first lower radio frequency index and then calibrating the first upper radio frequency index; while the uniform calibration strategy first adjusts the second upper radio frequency index and then calibrates the second lower radio frequency index. The residue calibration strategy is aimed at large deviations, and prioritizes adjusting the lower radio frequency power supply and then adjusting the upper radio frequency power supply; while the uniform calibration strategy is suitable for small deviations, and first adjusts the upper radio frequency power supply to ensure the consistency of the etching process, and both strategies realize the mutual coordinated calibration of the upper and lower radio frequency indicators, and in the residue retention scenario, it ensures rapid identification and coordinates the calibration of the upper and lower radio frequency power supplies for the different stages, ensuring the calibration accuracy, solving the technical problems of the prior art that the different stages of the residue retention scenario cannot be quickly identified and the method for the coordinated calibration of the output power of the upper and lower radio frequency power supplies for the different stages can be achieved, and the adaptability and flexibility of the etching process are improved, the predictability of the etching process is improved, and the technical effect of adapting to various complex etching environments is achieved.

[0026] In order to better understand the above technical solution, the following will be combined with the accompanying drawings and specific implementation methods.

[0027] An embodiment of the present invention is as follows. Figure 2 FIG. 1 is a schematic diagram of a structure of a radio frequency power supply output power calibration device in a semiconductor process method according to an embodiment of the present invention. Compared with the prior art, the present invention omits the following Figure 1 The phase-locked cable 14 in the prior art is used in this way. In the residue retention scenario of semiconductor etching, the hardware limitation of the phase-locked cable is broken through, and the calibrated RF output power can be quickly, flexibly and accurately responded to the residue retention scenario. Specifically, due to the breakthrough of the hardware limitation of the phase-locked cable, the software phase-locking of the present invention can break through the limitation of the hardware response speed, because the design of the phase-locked cable is optimized for stability rather than speed, which means that it does not respond quickly enough when dealing with rapidly changing dynamic conditions. The software phase-locking of the present invention can respond quickly, and the residue scenario in the semiconductor manufacturing process requires rapid power adjustment to ensure the efficiency and uniformity of the etching process. For example, the software phase-locking of the RF power output power calibration method of the present invention can support the rapid changes of physical and electrical characteristics. In addition, the software phase-locking also breaks the problem that the inherent physical characteristics of the phase-locked cable, such as inductance, capacitance and resistance, will affect the quality and accuracy of its transmission signal. When the RF power output needs to be accurately adjusted to cope with the impact of the previous batch of residues on the current etching process, it can be accurately adjusted to achieve the ideal etching effect.

[0028] Specifically, Figure 2As shown, it includes an improved process chamber 130, an improved upper RF power source 210 and an improved lower RF power source 50, wherein an improved base 100 (for example, an electrostatic chuck) for carrying an improved wafer 90 is provided in the improved process chamber 130, and the improved lower RF power source 50 is electrically connected to the improved base 100 through an improved lower matcher 40, so as to load bias power to the improved base 100. In addition, an improved dielectric window 80 is provided at the top of the improved process chamber 130, and an improved upper electrode is provided above the improved dielectric window 80, the improved upper electrode includes an improved outer coil 60 and an improved inner coil 70 of an improved inductive coupling coil, both of which are electrically connected to an improved current distribution unit 30, and the improved upper RF power source 10 is electrically connected to the improved current distribution unit 30 through an improved upper matcher 20, so as to load RF power to the improved outer coil 60 and the improved inner coil 70 through the improved upper matcher 20 and the improved current distribution unit 30, and the RF energy is coupled to the improved process chamber 130 through the improved dielectric window 80. In addition, an improved nozzle 120 is also provided on the improved dielectric window 80 for introducing process gas into the improved process chamber 130. The above-mentioned RF energy can excite the process gas to generate the improved plasma 110. In the embodiment of the present invention, the phase difference between the output waveforms of the improved upper RF power supply 210 and the improved lower RF power supply 50, that is, the common excitation (Common Exciter, CEX) phase-locking angle, can be adjusted by using a software phase-locking method, and the coupling phase difference between the improved upper electrode and the improved lower electrode of the improved process chamber 130 on the surface of the improved wafer 90 can be adjusted, thereby affecting the ion energy and sheath potential above the improved wafer 90, and then changing the etching rate and Map distribution of the improved wafer 90. Optionally, in the scenario of residue retention, the software phase-locking technology can be used, and the control of the RF power supply no longer depends on the physically connected phase-locking cable, but is adjusted and controlled by a software algorithm. The phase difference of the output waveform of the RF power supply is adjusted and controlled. Optionally, digital signal processing technology is used to accurately calculate and adjust the phase difference between the RF power supplies, allowing a more flexible and faster response to the impact of residues on the etching process.

[0029] Figure 3 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by an embodiment of the present invention is shown in FIG. Figure 3 As shown, the following steps are included:

[0030] Step 310, obtaining a first survival indicator, wherein the first survival indicator is calculated based on a first etching rate and a first plasma density change rate, wherein the first etching rate and the first plasma density change rate are both obtained within a first time T1 of a semiconductor etching region, wherein the first survival indicator is positively correlated with the first plasma density change rate and is negatively correlated with the first etching rate; wherein the semiconductor etching region may be as follows Figure 2The semiconductor etching area near the wafer 90 is improved.

[0031] Specifically, in the presence of residue etching scenarios, especially when using plasma for etching, the impact of residues is a key issue, which can significantly affect the efficiency and uniformity of the etching process. Therefore, quickly and accurately evaluating the impact of residues is essential to ensure semiconductor manufacturing quality and yield. First of all, the reason why the first residual index is positively correlated with the first plasma density change rate is that a high first plasma density change rate indicates that more active plasma particles will participate in the etching process, and a positive correlation means that when the value of one variable increases, the value of the other variable will also increase. The first residual index is positively correlated with the first plasma density change rate, which means that when the first plasma density change rate increases, the first residual index will also increase. This relationship generally indicates that an increase in the plasma density change rate reflects more plasma activity because more residues need to be processed or because the etching process requires more energy to overcome the obstacles caused by the residues. In the case of more residues, more plasma energy is required to remove these residues or adjust the etching process to achieve the desired etching depth and morphology. Therefore, when the plasma density change rate is high, it can be quantified that the impact of the residue is greater. Secondly, the first residual index is inversely correlated with the first etch rate, and inverse correlation means that when the value of one variable increases, the value of the other variable decreases. The first residual index is inversely correlated with the first etch rate, indicating that when the etch rate increases, the first residual index decreases. Because a higher etch rate indicates that the etching process is smoother and the residue has less impact, the first residual index (reflecting the amount or impact of the residue) decreases accordingly. This is because the etching rate is a direct indicator for evaluating the efficiency of the etching process. Ideally, there should be a higher etching rate in the absence of residues because the etching process is not hindered. However, when residues are present, these substances hinder the interaction between the plasma and the wafer surface, thereby reducing the etching rate. Therefore, a low first etching rate means a higher residue impact, making the first residual index inversely correlated with the first etching rate, thereby reflecting the hindering effect of residues on etching efficiency. When the first residual index is high, it indicates that the residue has a greater impact on the etching process. This is because the amount of residues is large, or the type of residues has a strong absorption or shielding effect on the plasma, which hinders the effective action of the plasma. Therefore, a high value for this indicator directly reflects the significant role of carryover in the batch.

[0032] Optionally, the first survival index may be obtained by the following formula: R = w Δρ *Norm Δρ +w ER *(1-Norm ER ), where: Norm Δρ=(Δρ-Δρ min ) / (Δρ max -Δρ min );Norm ER =(ER-ER min ) / (ER max -ER min ), where ER is the first etching rate. Δρ is the first plasma density change rate. ER min and ER max are the minimum and maximum values ​​of the first etch rate observed. Δρ min and Δρ max are the minimum and maximum values ​​of the observed first plasma density change rate. Δρ is the weight of the normalized first plasma density change rate. ER is the weight of the normalized first etch rate. Δρ :Use the normalized plasma density change rate directly, because it is positively correlated with the residual index. The more residues there are, the greater the plasma change rate may be. ER : Use 1 minus the normalized etch rate, because a lower etch rate may indicate a greater residue impact, so it is inversely correlated with the residual index. This formula intuitively reflects the impact of residues on the etching process. By normalizing, it ensures the comparability of data under different equipment or conditions, helps to quickly adjust process parameters to cope with the impact of residues and maintain the stability and efficiency of the production process.

[0033] Step 320, obtaining a reference etching stability index, the reference etching stability index is calculated based on a reference etching rate and a reference plasma density change rate, the reference etching rate and the reference plasma density change rate are both obtained within a first time T1 of the semiconductor etching region; wherein the semiconductor etching region may be as follows Figure 2 Improve the semiconductor etching area near the wafer 90. Wherein, the reference etching stability index is positively correlated with the reference plasma density change rate and negatively correlated with the reference etching rate;

[0034] Specifically, the same calculation method of the first residual index is used to obtain the benchmark etching stability index, so that the subsequent comparison results can be obtained more accurately and effectively. In the process of semiconductor etching, especially when facing residue retention scenarios, it is crucial to identify and adapt to different etching stages. The setting of the benchmark etching stability index is intended to provide a reference point for this process, so that the deviation between the current etching operation and the ideal or expected operating conditions can be measured. This indicator needs to be combined with the etching rate and the rate of change of plasma density. These two parameters are key factors in evaluating semiconductor etching efficiency and quality.

[0035] Step 330 , obtaining a first comparison index according to the first survival index and the reference etching stability index, wherein the first comparison index is the first survival index divided by the reference etching stability index.

[0036] Specifically, by dividing the first residual index by the benchmark etching stability index, the obtained comparative index is a ratio, which directly represents the performance of the current batch relative to the ideal or benchmark conditions. Using the comparative index in the form of a ratio, it is easier to set a unified control threshold and strategy. For example, a fixed ratio threshold (such as 1.2) can be set based on experience or experimental data to determine when specific calibration measures should be taken. This approach simplifies the control logic and makes the response strategy more direct and clear.

[0037] Step 340: compare the first comparison index with the first threshold to obtain a comparison result.

[0038] Specifically, the first threshold value needs to be set at a reasonable level to distinguish different etching states and necessary adjustment levels. This threshold value represents that when the ratio of the first residual index to the benchmark etching stability index exceeds a certain value, specific calibration measures need to be taken. First, evaluate the sensitivity of the etching process: The first step is to evaluate the sensitivity of the etching process to residues. If the residue has a greater impact on the etching process (for example, it affects the etching uniformity or rate), a lower threshold value is required to facilitate earlier identification and response to these changes. Second, historical data analysis: By analyzing the ratio of the first residual index to the benchmark etching stability index in the historical data, the critical points that affect the yield or quality can be identified. It is key to select a threshold value that can reflect obvious changes and has significant differences in the effects before and after. Third, experimental determination: Through controlled experiments, the amount of residue is changed to observe the impact of different levels of residue on the etching process. Record the ratio of the first residual index to the benchmark etching stability index under these conditions to determine a threshold value based on an experiment. Optionally, for a specific example, optionally, through data analysis, it is found that when the ratio of the first residual index to the benchmark etching stability index is greater than 1.2, the etching process begins to show a significant quality decline. In this case, 1.2 can be set as the first threshold. This means: if the first comparison index (such as 1.3 or higher) indicates that the residue of the current batch has a greater impact on etching, a residue calibration strategy needs to be adopted. If the first comparison index is lower than 1.2 (such as 1.1), it indicates that the current residue level is still within a controllable range.

[0039] Step 350: If the comparison result satisfies the first comparison range, a residue calibration strategy is executed, wherein the residue calibration strategy includes: first calibrating the first lower RF indicator and then calibrating the first upper RF indicator according to the comparison result, wherein the first lower RF indicator and the first upper RF indicator both include RF power supply output power.

[0040] Specifically, after confirming the specific stage of the residue influence, this scheme first adjusts the lower RF power supply to stabilize the base potential, and then adjusts the upper RF power supply to optimize plasma generation to achieve the best etching effect. This collaborative calibration takes into account the mutual influence of the upper and lower RF power supplies at different etching stages, thereby ensuring the maximum uniformity and efficiency of the etching process. The technical effects of adopting the residue calibration strategy are: First, strong targeting: At the beginning of etching, due to the presence of residues, stronger RF indicators are required to remove the residues and stabilize the etching environment. The lower RF power supply indicator is adjusted first because it is directly connected to the base in contact with the wafer, and the bias on the wafer can be adjusted quickly to quickly process the residues, thereby improving etching uniformity and efficiency. Second, fast response: After quickly adjusting the lower RF power supply, the adjustment of the upper RF power supply indicator can more finely control the density and energy distribution of the plasma and optimize the overall etching process.

[0041] Step 360, if the comparison result satisfies the second comparison range, a uniform calibration strategy is executed, wherein the uniform calibration strategy includes: calibrating the second upper RF indicator first and then the second lower RF indicator according to the comparison result, wherein the second lower RF indicator and the second upper RF indicator both include the RF power supply output power.

[0042] Specifically, the technical effects of adopting the uniform calibration strategy are: First, maintain process uniformity: After the etching process reaches a relatively stable state, the uniform calibration strategy can uniformly control the plasma state in the entire chamber by first adjusting the upper RF power supply, and then fine-tune the wafer contact potential through the lower RF power supply to maintain the etching depth and uniformity. Second, improve the etching quality: By optimizing the global distribution of plasma and locally adjusting the wafer potential, over-etching and under-etching can be reduced, and the product yield can be improved.

[0043] Furthermore, the residue calibration strategy and the uniformity calibration strategy also have significant effects in overall synergy: First, dynamic identification and rapid response: By real-time monitoring of the etching rate and the rate of change of plasma density, the presence of residues and their specific impact on the etching process can be quickly identified. The real-time identification capability allows the adjustment strategy of the RF power supply output index to quickly adapt to changes in the etching process, especially the transition from the residue treatment stage to the stable etching stage. This rapid response mechanism ensures that immediate action is taken when changes in etching conditions are detected, reducing etching quality problems caused by delayed adjustments. Second, coordinated adjustment of the upper and lower RF power supplies: In the residue removal stage, the strategy first adjusts the lower RF power supply to stabilize the potential of the wafer base and effectively treat the residues, and then adjusts the upper RF power supply to optimize the plasma conditions to achieve rapid and effective residue removal. When the etching process reaches a more stable state, the plasma environment of the entire chamber is adjusted by first optimizing the upper RF power supply, and then fine-tuning is performed through the lower RF power supply to maintain the etching depth and uniformity. This coordinated adjustment strategy ensures the optimal distribution of RF energy at all stages. Third, enhance the uniformity and quality of the etching process: The collaborative calibration strategy provides sufficient energy for treating residues in the initial stage through orderly adjustment of the upper and lower RF power supplies, and also ensures the uniformity and repeatability of the process when the etching process enters the stable stage. This allows each etching stage to obtain the most suitable RF power setting, thereby maximizing etching efficiency and product quality and reducing the defective product rate.

[0044] One embodiment of the present invention, Figure 4 A flowchart of a method for calibrating the output power of a radio frequency power supply provided in another embodiment of the present invention further includes before obtaining the first residual indicator of the semiconductor etching region.

[0045] Step 410, obtaining etching benchmark indicators, which include physical and chemical indicators of the semiconductor to be etched, etching environment indicators, and etching gas characteristic indicators.

[0046] Specifically, the etching benchmark index is a set of parameters that measure and describe various environmental and material conditions during the etching process. The etching benchmark index is determined through a series of preliminary tests at the beginning of setting the process parameters, and is used as a standard for performance comparison and calibration in the subsequent production process. The physical indicators of the semiconductor to be etched include the thickness, flatness, surface roughness, etc. of the semiconductor wafer, which directly affect the uniformity and accuracy of the etching process. The chemical indicators of the semiconductor to be etched involve the material composition and impurity content of the wafer, which affect the etching rate and the surface quality after etching. The etching environment indicators include the temperature, humidity, and cleanliness level of the clean room during the etching process. Fluctuations in environmental conditions can have a significant impact on the etching results, so they must be strictly controlled. The etching gas characteristic indicators involve the type of etching gas used, flow rate, pressure, and gas purity. Different gases and gas conditions (such as flow rate and pressure) will directly determine the characteristics of the plasma, thereby affecting the etching rate and uniformity.

[0047] Step 420: determine an upper RF reference indicator and a lower RF reference indicator according to the etching reference indicator, wherein the upper RF reference indicator includes an upper RF reference power and an upper RF reference frequency, and the lower RF reference indicator includes a lower RF reference power and a lower RF reference frequency.

[0048] Specifically, the most reasonable upper RF benchmark indicator and lower RF benchmark indicator corresponding to the etching benchmark indicator can be determined according to the preliminary experiment. For example, a silicon-based material with standard physical and chemical properties needs to be etched in the semiconductor manufacturing process. The etching benchmark indicators have been obtained through a series of preliminary tests. The etching benchmark indicators are: Physical indicators: The thickness of the silicon wafer is 200μm. Chemical indicators: CF4 is used as the main etching gas. Etching environment indicators: The environment at room temperature, the pressure is set to 50mTorr. Step 420 is performed as follows: First, determine the upper RF benchmark indicator, the upper RF benchmark power: Since the etching of silicon requires a higher plasma density to increase the etching rate, a higher power setting will be selected. Based on previous experimental data, the selected power may be between 300 and 500W to ensure the effective generation and maintenance of plasma. Upper RF reference frequency: High frequency helps to quickly excite and maintain plasma. For CF4 etching of silicon materials, 13.56MHz is used to optimize energy transfer. Second, determine the lower RF benchmark indicators, including the lower RF benchmark power: The lower RF is mainly used to adjust the ion energy and control the properties of ion bombardment of the wafer. In order to control the etching depth and profile, the lower RF power is usually low, such as 50 to 200W. For the lower RF benchmark frequency, low frequency helps to increase the bombardment energy of ions, ranging from 400kHz to 2MHz, to improve the energy distribution of ions and etching uniformity.

[0049] Step 430: Perform RF output of the upper RF power supply according to the upper RF reference index.

[0050] Step 440: Perform RF output of the lower RF power supply according to the lower RF reference indicator.

[0051] In one embodiment of the present invention, the first comparison range is a range in which the first comparison index is greater than or equal to the first threshold.

[0052] Specifically, the presence of residues during the etching process can significantly affect the etching efficiency and results, especially when the residues affect the stability of the plasma or directly hinder the etching material. In this case, the first residual index will be relatively high because it includes the high plasma density change rate and the low etching rate, both of which are associated with the situation of more residues. The first comparative index (the first residual index divided by the benchmark etching stability index) is to quantify the deviation between the current batch and the ideal or benchmark conditions. When this ratio is greater than or equal to the first threshold, it means that the etching state of the current batch is significantly different from the benchmark state and needs to be adjusted.

[0053] According to the comparison result, calibrating the first lower RF index first and then calibrating the first upper RF index includes: calibrating the lower RF reference index to the first lower RF index according to the comparison result, and calibrating the upper RF reference index to the first upper RF index according to the first lower RF index, wherein the first upper RF index includes the first upper RF power and the first upper RF frequency, and the first lower RF index includes the first lower RF power and the first upper RF frequency. Among them, in the residue calibration scenario, the power and frequency of the RF power supply are key parameters, which have a direct impact on the control of the etching process. Adjusting these two parameters can not only optimize the etching process, but also deal with the instability caused by residues. The following are the main advantages and reasons for adjusting power and frequency: First, enhance the flexibility and accuracy of the etching process: First, power adjustment: RF power directly affects the density and energy of the plasma, and then affects the etching rate and depth. Adjusting the power can help control the activity of the plasma during the etching process, especially in the case of more residues, increasing the power helps to accelerate the removal of the etching material. Secondly, frequency adjustment: The RF frequency determines the acceleration and collision frequency of electrons in the plasma, which in turn affects the ionization efficiency and energy distribution of the plasma. Adjusting the frequency can help optimize the interaction between the plasma and the material surface, making the etching process more uniform and effective. Second, adapt to different etching needs: In batches where residues have a significant impact, adjusting the power alone is not enough to achieve the desired etching effect. Frequency adjustment can provide additional control measures to more comprehensively address the etching problems caused by residues by changing the ionization characteristics and the reaction kinetics of the plasma. Third, improve etching uniformity and quality: Combining power and frequency adjustments can more finely control the generation and maintenance of plasma, especially in complex semiconductor materials and structures. This comprehensive regulation helps reduce etching non-uniformity caused by uneven plasma distribution, thereby improving product consistency and reliability. Fourth, optimize energy use and efficiency: Accurate power and frequency adjustment can avoid excessive use of RF energy, reduce energy consumption, and ensure etching efficiency and effect. This optimization makes the process more economical while reducing equipment wear and maintenance requirements.

[0054] Specifically, if the first comparison index shows that the residue has a greater impact (i.e., the index is higher than or equal to the threshold), the lower RF power supply (responsible for providing the base bias power and affecting the ion bombardment energy) is adjusted first, and then the upper RF power supply (responsible for plasma generation) is adjusted. This sequence ensures that the main problems affecting the etching depth and rate are solved first, and then the generation and maintenance of plasma are optimized to restore to the ideal etching conditions.

[0055] One embodiment of the present invention, Figure 5 and Figure 6 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by another embodiment of the present invention includes the following steps.

[0056] Step 510: Determine a first compensation power and a first compensation frequency according to the comparison result.

[0057] Wherein, determining the first compensation power and the first compensation frequency according to the comparison result also includes: step 610, obtaining a first power compensation factor and a first frequency compensation factor according to a first comparison index and a first threshold.

[0058] Specifically, the method for calculating the compensation factor, optionally, the first power compensation factor (P factor ): A linear or nonlinear model may be used to calculate the required power adjustment amount according to the difference between the first comparison index and the first threshold. For example, formula example: P factor =k p *(first comparison index-first threshold), where k p is a preset constant used to determine the sensitivity of power adjustment. The first frequency compensation factor (F faceor ): Similarly, the required frequency adjustment is determined based on the difference between the first comparison index and the first threshold. Formula example: F faceor =k f *(first comparison index - first threshold), where kf is a preset constant used to determine the sensitivity of frequency adjustment. Implementation adjustment: According to the calculated first power compensation factor and first frequency compensation factor, adjust the output power and frequency of the RF power supply to cope with the influence of the residue and restore the stability and efficiency of the etching process. For example: For example, if the first comparison index is 1.2, the first threshold is set to 1.0, kf p =0.05, k f =0.02; first power compensation factor: P factor =0.05*(1.2-1.0)=0.01 (indicates that the power needs to be increased by 1%), the first frequency compensation factor: F factor = 0.02*(1.2-1.0) = 0.004 (indicates that the frequency needs to be increased by 0.4%). Among them, the constant k in the compensation factor is determined p and k f It can be determined through historical data analysis, process sensitivity testing, simulation and modeling. For example, optional, first, data collection: collect sufficient operating data, especially system response data when changing RF settings. Second, conduct small-scale experiments: change RF settings in a controlled environment, record etching rate, plasma changes, chip quality, etc. Third, data analysis and model verification: use statistical and modeling tools to analyze experimental data and verify the predictive accuracy of the model. Fourth, expert review: let experienced engineers and technical experts review the model and experimental results and provide feedback. Fifth, set and optimize the constant k in the compensation factor. p and kf .

[0059] Step 620, obtaining a first compensation power according to a first power compensation factor and a lower RF reference power; Step 630, obtaining a first compensation frequency according to a first frequency compensation factor and a lower RF reference frequency.

[0060] Specifically, the reference power and frequency are adjusted by applying the compensation factor, wherein the first compensation power = the lower RF reference power × (1 + P factor ), and the first compensation frequency = lower RF reference frequency × (1 + F factor ). For example: if the reference power is 1000W and the reference frequency is 13MHz. The first compensation power = 1000W×(1+0.01)=1010W; the first compensation frequency = 13MHz×(1+0.004)=13.052MHz, where P factor is the first power compensation factor. F factor is the first frequency compensation factor.

[0061] Step 520: calibrate the lower radio frequency reference power to the first lower radio frequency power according to the first compensation power.

[0062] Specifically, the first lower RF power is set equal to the first compensation power. For example, according to the above example, the lower RF power is set to the first compensation power of 1010W.

[0063] Step 530: calibrate the lower RF reference frequency to the first lower RF frequency according to the first compensation frequency.

[0064] Specifically, the first lower radio frequency frequency is set equal to the first compensation power. According to the above example, the lower radio frequency power is set equal to the first compensation power and the first compensation frequency 13.052 MHz.

[0065] Step 540: calibrate the upper RF reference power to the first upper RF power according to the first lower RF power and the reference phase-locking angle.

[0066] Specifically, the reference phase-locking angle may be set according to a pre-experimental or simulation method.

[0067] Step 550, calibrating the upper RF reference frequency to the first upper RF frequency according to the first lower RF frequency and a reference frequency adjustment factor, wherein the reference frequency adjustment factor is obtained according to the conductivity and ionization rate of the reference plasma, the lower RF reference frequency, and the upper RF reference frequency in the reference state;

[0068] Specifically, the reference frequency adjustment factor may be set according to a pre-experimental or simulation method.

[0069] After calibrating the upper radio frequency reference indicator to the first upper radio frequency indicator according to the first lower radio frequency indicator, it also includes:

[0070] Step 560, performing RF output of the lower RF power supply according to the first lower RF power and the first lower RF frequency;

[0071] Step 570: Perform RF output of the upper RF power source according to the first upper RF power and the first upper RF frequency.

[0072] In one embodiment of the present invention, the second comparison range is a range in which the first comparison index is less than the first threshold value; when the first comparison index is less than the first threshold value, it means that the residue has little effect on the etching process. This small deviation indicates that the etching conditions of the current batch are less affected by the residue, and more attention needs to be paid to the uniformity and consistency of etching.

[0073] Calibrating the second upper RF indicator first and then the second lower RF indicator according to the comparison result includes: calibrating the upper RF reference indicator to the second upper RF indicator according to the comparison result, and calibrating the lower RF reference indicator to the second lower RF indicator according to the second upper RF indicator, wherein the second upper RF indicator includes a second upper RF power and a second upper RF frequency, and the second lower RF indicator includes a second lower RF power and a second upper RF frequency.

[0074] One embodiment of the present invention, Figure 7 and Figure 8 A flowchart of a method for calibrating the output power of a radio frequency power supply provided by another embodiment of the present invention includes the following steps.

[0075] The upper RF reference index is calibrated as a second upper RF index according to the comparison result, and further includes: step 710, determining to perform a second plasma density change rate detection according to the comparison result, the second plasma density change rate being a plasma density change rate of the upper RF nozzle region within the first time T1;

[0076] Step 720, determining a second compensation power and a second compensation frequency according to a second plasma density change rate;

[0077] Wherein, determining the second compensation power and the second compensation frequency according to the second plasma density change rate also includes: step 810, obtaining a second reference plasma density change rate, where the second reference plasma density change rate is a reference plasma density change rate of the upper RF nozzle region within the first time T1;

[0078] Step 820, obtaining a second difference change rate according to the second reference plasma density change rate and the second reference plasma density change rate, wherein the second difference change rate is an absolute value of the difference between the second reference plasma density change rate and the second reference plasma density change rate;

[0079] Step 830, comparing the second difference change rate with the second threshold;

[0080] Step 840: If the second difference change rate is greater than the second threshold, obtain a second power compensation factor and a second frequency compensation factor according to the second difference change rate and the second threshold; obtain a second compensation power according to the second power compensation factor and the upper RF reference power; obtain a second compensation frequency according to the second frequency compensation factor and the upper RF reference frequency;

[0081] Step 850: If the second difference change rate is less than the second threshold, determine that the second compensation power and the second compensation frequency are both 0. Specifically, if the second difference change rate is less than the second threshold, the uniformity of the surface etching meets the requirements and no adjustment is required.

[0082] Step 730: calibrate the upper RF reference power to the second upper RF power according to the second compensation power. Specifically, the second upper RF power is set equal to the second compensation power.

[0083] Step 740: calibrate the upper RF reference frequency to the second upper RF frequency according to the second compensation frequency. Specifically, the second upper RF frequency is set equal to the second compensation frequency.

[0084] Calibrate the lower RF reference indicator to the second lower RF indicator according to the second upper RF indicator, further comprising: step 750, calibrating the lower RF reference power to the second lower RF power according to the second upper RF power and the reference phase-locking angle;

[0085] Step 760, calibrating the lower RF reference frequency to the second lower RF frequency according to the second upper RF frequency and the reference frequency adjustment factor; the reference frequency adjustment factor is obtained according to the conductivity and ionization rate of the reference plasma, the lower RF reference frequency, and the upper RF reference frequency in the reference state;

[0086] After the lower RF reference index is calibrated to the second lower RF index according to the second upper RF index, the method further includes: step 770, performing RF output of the upper RF power supply according to the second upper RF power and the second upper RF frequency;

[0087] Step 780: Perform RF output of the lower RF power supply according to the second lower RF power and the second lower RF frequency.

[0088] A preferred embodiment of the above steps 710-780, specifically, in the first aspect, the second plasma density change rate is the change rate of the plasma density measured in the upper RF nozzle area within a specific time point T1. This change rate reflects the change in plasma density from the start of the etching process to the current time point, and is an important indicator for judging the uniformity of the current etching state. In the second aspect, the second difference change rate is the absolute value of the difference between the second plasma density change rate and the second reference plasma density change rate (a change rate under ideal or normal etching conditions). This difference indicates the deviation between the actual etching state and the ideal state. In the third aspect, the second threshold is a preset standard used to determine whether the second difference change rate is within an acceptable range. If the second difference change rate exceeds this threshold, it means that the current etching state deviates greatly from the uniform state, and the etching uniformity and consistency need to be adjusted. In the fourth aspect, the second power compensation factor and the second frequency compensation factor: These compensation factors are calculated based on the difference between the second difference change rate and the second threshold. They determine how much power and frequency need to be adjusted in order to bring the etching process back to a uniform state. The fifth aspect, the second compensation power and the second compensation frequency: According to the second power compensation factor and the second frequency compensation factor, calculate the specific power and frequency values ​​that need to be adjusted. These adjustments directly affect the output of the RF power supply, thereby affecting the characteristics of the plasma and the etching process. In a preferred example, assume that the second reference plasma density change rate is 2% / min, and the measured second plasma density change rate is 5% / min. Set the second threshold to 1% / min. First, calculate the second difference change rate: the second difference change rate = |5%-2%| = 3% / min. Second, compare with the second threshold: 3%>1%, indicating that adjustment is needed; third, set the compensation coefficient: Assume that the second power compensation coefficient (k p )=0.1 and the second frequency compensation factor (k f )=0.05, where the second power compensation coefficient (k p ) and the second frequency compensation factor (k f ) can be obtained based on preliminary experiments or data modeling. Third, calculate the compensation factor: the second power compensation factor = 0.1*(3%-1%) = 0.2; the second frequency compensation factor = 0.05*(3%-1%) = 0.1; Fourth, apply compensation: if the lower RF reference power is 1000W and the reference frequency is 13MHz, then: the second compensation power = 1000W+(1000W*0.2) = 1200W; the second compensation frequency = 13MHz+(13MHz*0.1) = 14.3MHz. In this way, by adjusting the RF power and frequency according to the changes in plasma density, the etching process can be effectively controlled to ensure product quality and process stability.

[0089] An embodiment of the present invention provides a radio frequency power supply output power calibration device, which is used to implement the calibration method, and includes: a first residual index acquisition unit, which is used to acquire a first residual index, and the first residual index is calculated based on a first etching rate and a first plasma density change rate, and the first etching rate and the first plasma density change rate are both acquired within a first time T1 in a semiconductor etching region, wherein the first residual index is positively correlated with the first plasma density change rate and is negatively correlated with the first etching rate; a reference etching stability index acquisition unit, which is used to acquire a reference etching stability index, and the reference etching stability index is calculated based on a reference etching rate and a reference plasma density change rate, and the reference etching rate and the reference plasma density change rate are both acquired within the first time T1 in the semiconductor etching region; a first comparison index determination unit, which is used to A first comparison index is obtained according to the first residual index and the benchmark etching stability index, and the first comparison index is the first residual index divided by the benchmark etching stability index; a comparison unit is used to compare the first comparison index with the first threshold value to obtain a comparison result; a residue calibration unit is used to execute a residue calibration strategy if the comparison result meets the first comparison range, and the residue calibration strategy includes: according to the comparison result, first calibrate the first lower RF index and then calibrate the first upper RF index, and the first lower RF index and the first upper RF index both include the RF power supply output power; a uniform calibration unit is used to execute a uniform calibration strategy if the comparison result meets the second comparison range, and the uniform calibration strategy includes: according to the comparison result, first calibrate the second upper RF index and then calibrate the second lower RF index, and the second lower RF index and the second upper RF index both include the RF power supply output power.

[0090] Another embodiment of the present invention is a semiconductor process method, which includes a semiconductor etching process method, and the semiconductor etching process method includes the RF power supply output power calibration method as described above.

[0091] Fig. 9 An example of a physical structure diagram of an electronic device is shown in FIG. Fig. 9 As shown, the electronic device 900 may include: a processor 901, a communication interface 902, a memory 903 and a communication bus 904, wherein the processor 901, the communication interface 902 and the memory 903 communicate with each other through the communication bus 904. The processor 901 may call the logic instructions in the memory 903 to execute the dust removal parameter control method based on the surface roughness of the perovskite battery layer provided by the above methods.

[0092] In addition, the logic instructions in the above-mentioned memory 903 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0093] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the dust removal parameter control method based on the surface roughness of the perovskite battery layer provided by the above methods.

[0094] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0095] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute each embodiment or some part of the embodiment.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calibrating the output power of a radio frequency power supply, characterized in that: include: Obtaining a first survival indicator, wherein the first survival indicator is calculated based on a first etching rate and a first plasma density change rate, wherein the first etching rate and the first plasma density change rate are both obtained within a first time T1 in a semiconductor etching region, wherein the first survival indicator is positively correlated with the first plasma density change rate and is inversely correlated with the first etching rate; Obtaining a reference etching stability index, wherein the reference etching stability index is calculated based on a reference etching rate and a reference plasma density change rate, wherein the reference etching rate and the reference plasma density change rate are both obtained within a first time T1 of the semiconductor etching region; Obtaining a first comparison index according to the first residual index and the reference etching stability index, wherein the first comparison index is the first residual index divided by the reference etching stability index; Comparing the first comparison index with the first threshold value to obtain a comparison result; Wherein, if the comparison result satisfies the first comparison range, a residue calibration strategy is executed, and the residue calibration strategy includes: first calibrating the first lower RF index and then calibrating the first upper RF index according to the comparison result, and the first lower RF index and the first upper RF index both include RF power supply output power; If the comparison result satisfies the second comparison range, a uniform calibration strategy is executed, wherein the uniform calibration strategy includes: calibrating the second upper RF indicator first and then the second lower RF indicator according to the comparison result, wherein the second lower RF indicator and the second upper RF indicator both include the RF power supply output power.

2. The method according to claim 1, characterized in that Before obtaining the first residual index of the semiconductor etching region, the method further includes: Obtaining etching benchmark indicators, wherein the etching benchmark indicators include physical and chemical indicators of the semiconductor to be etched, etching environment indicators, and etching gas characteristic indicators; Determine an upper RF reference index and a lower RF reference index according to the etching reference index, wherein the upper RF reference index includes an upper RF reference power and an upper RF reference frequency, and the lower RF reference index includes a lower RF reference power and a lower RF reference frequency; Performing RF output of the upper RF power supply according to the upper RF benchmark indicator; The RF output of the lower RF power supply is performed according to the lower RF reference index.

3. The method according to claim 2, characterized in that include: The first comparison range is a range in which the first comparison index is greater than or equal to the first threshold; Calibrating the first lower RF indicator first and then the first upper RF indicator according to the comparison result includes: calibrating the lower RF reference indicator to the first lower RF indicator according to the comparison result, and calibrating the upper RF reference indicator to the first upper RF indicator according to the first lower RF indicator, wherein the first upper RF indicator includes a first upper RF power and a first upper RF frequency, and the first lower RF indicator includes a first lower RF power and a first upper RF frequency.

4. The method according to claim 3, characterized in that Calibrating the lower RF reference index to the first lower RF index according to the comparison result, further comprising: determining a first compensation power and a first compensation frequency according to the comparison result; calibrating the lower RF reference power to the first lower RF power according to the first compensation power; calibrating the lower RF reference frequency to the first lower RF frequency according to the first compensation frequency; The method further comprises: calibrating the upper RF reference index to the first upper RF index according to the first lower RF index and the reference phase-locked angle to the first upper RF power; calibrating the upper RF reference frequency to the first upper RF frequency according to the first lower RF frequency and the reference frequency adjustment factor, wherein the reference frequency adjustment factor is obtained according to the conductivity and ionization rate of the reference plasma, the lower RF reference frequency, and the upper RF reference frequency in the reference state; After calibrating the upper RF reference indicator to the first upper RF indicator according to the first lower RF indicator, it also includes: performing RF output of the lower RF power supply according to the first lower RF power and the first lower RF frequency; performing RF output of the upper RF power supply according to the first upper RF power and the first upper RF frequency.

5. The method according to claim 4, characterized in that The determining the first compensation power and the first compensation frequency according to the comparison result includes: Obtaining a first power compensation factor and a first frequency compensation factor according to a first comparison index and a first threshold; Obtaining a first compensation power according to the first power compensation factor and the lower radio frequency reference power; A first compensation frequency is obtained according to the first frequency compensation factor and the lower radio frequency reference frequency.

6. The method according to claim 2, characterized in that include: The second comparison range is a range in which the first comparison index is less than the first threshold; Calibrating the second upper RF indicator first and then the second lower RF indicator according to the comparison result includes: calibrating the upper RF reference indicator to the second upper RF indicator according to the comparison result, and calibrating the lower RF reference indicator to the second lower RF indicator according to the second upper RF indicator, wherein the second upper RF indicator includes a second upper RF power and a second upper RF frequency, and the second lower RF indicator includes a second lower RF power and a second upper RF frequency.

7. The method according to claim 6, characterized in that The upper RF reference index is calibrated to a second upper RF index according to the comparison result, and further includes: determining to perform a second plasma density change rate detection according to the comparison result, wherein the second plasma density change rate is a plasma density change rate of the upper RF nozzle region within the first time T1; determining a second compensation power and a second compensation frequency according to the second plasma density change rate; calibrating the upper RF reference power to a second upper RF power according to the second compensation power; and calibrating the upper RF reference frequency to a second upper RF frequency according to the second compensation frequency; The method further comprises: calibrating the lower RF reference index to the second lower RF index according to the second upper RF index, and further comprising: calibrating the lower RF reference power to the second lower RF power according to the second upper RF power and the reference phase-locked angle; calibrating the lower RF reference frequency to the second lower RF frequency according to the second upper RF frequency and the reference frequency adjustment factor; the reference frequency adjustment factor is obtained according to the conductivity and ionization rate of the reference plasma, the lower RF reference frequency and the upper RF reference frequency in the reference state; After calibrating the lower RF reference indicator to the second lower RF indicator according to the second upper RF indicator, it also includes performing RF output of the upper RF power supply according to the second upper RF power and the second upper RF frequency; and performing RF output of the lower RF power supply according to the second lower RF power and the second lower RF frequency.

8. The method according to claim 7, characterized in that Determining a second compensation power and a second compensation frequency according to a second plasma density change rate also includes: Acquire a second reference plasma density change rate, where the second reference plasma density change rate is a reference plasma density change rate of the upper RF nozzle region within a first time T1; Obtaining a second difference change rate according to the second reference plasma density change rate and the second reference plasma density change rate, wherein the second difference change rate is an absolute value of a difference between the second reference plasma density change rate and the second reference plasma density change rate; Comparing the second difference change rate with a second threshold; If the second difference change rate is greater than the second threshold, a second power compensation factor and a second frequency compensation factor are obtained according to the second difference change rate and the second threshold; a second compensation power is obtained according to the second power compensation factor and the upper RF reference power; and a second compensation frequency is obtained according to the second frequency compensation factor and the upper RF reference frequency; If the second difference change rate is less than the second threshold, it is determined that the second compensation power and the second compensation frequency are both zero.

9. A radio frequency power supply output power calibration device, used to implement the calibration method according to any one of claims 1 to 8, characterized in that: include: A first survival index acquisition unit, used to acquire a first survival index, wherein the first survival index is calculated based on a first etching rate and a first plasma density change rate, wherein the first etching rate and the first plasma density change rate are both acquired within a first time T1 of a semiconductor etching region, wherein the first survival index is positively correlated with the first plasma density change rate and negatively correlated with the first etching rate; A reference etching stability index acquisition unit, used to acquire a reference etching stability index, wherein the reference etching stability index is calculated based on a reference etching rate and a reference plasma density change rate, wherein the reference etching rate and the reference plasma density change rate are both acquired within a first time T1 of the semiconductor etching region; A first comparison index determination unit, configured to obtain a first comparison index according to the first residual index and a reference etching stability index, wherein the first comparison index is the first residual index divided by the reference etching stability index; A comparison unit, used for comparing the first comparison index with the first threshold value to obtain a comparison result; An execution residue calibration unit is used to execute a residue calibration strategy if the comparison result satisfies a first comparison range, wherein the residue calibration strategy includes: first calibrating a first lower radio frequency index and then calibrating a first upper radio frequency index according to the comparison result, wherein both the first lower radio frequency index and the first upper radio frequency index include radio frequency power supply output power; A uniform calibration unit is used to execute a uniform calibration strategy if the comparison result satisfies a second comparison range. The uniform calibration strategy includes: calibrating the second upper RF indicator first and then calibrating the second lower RF indicator according to the comparison result. The second lower RF indicator and the second upper RF indicator both include the RF power supply output power.

10. A semiconductor process method, characterized in that: The semiconductor process method includes a semiconductor etching process method, and the semiconductor etching process method includes a radio frequency power supply output power calibration method according to any one of claims 1 to 8.

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