Impedance matching method and semiconductor device

Abstract

The present invention discloses an impedance matching method and a semiconductor device. The impedance matching method comprises: determining a preset amplitude and a preset phase of the output impedance of a power supply; collecting the amplitude and the phase of the input end of a matcher; determining that the average value of the reflected power of the power supply in a current time period is less than a critical value of a bad reflected power when the difference between the amplitude and the preset amplitude is less than a first difference and the difference between the phase and the preset phase is less than a second difference; determining a first risk number of times that each voltage value at the output end of the matcher in the current time period is greater than a voltage threshold or a second risk number of times that each current value is greater than a current threshold; when the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and the phase make the output impedance of the power supply match the load impedance of the equipment chamber. The present invention can realize fast, stable and efficient impedance matching and improve the stability of process results.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an impedance matching method and a semiconductor device. Background Art

[0002] Inductively coupled plasma source (ICP) is widely used in the field of semiconductor equipment manufacturing. Its main principle is: the RF power output by the RF power supply generates an alternating electromagnetic field in the chamber in the form of RF current through an inductive load coil (coil), thereby exciting the gas to generate plasma through the generated vortex electric field, and the electrostatic adsorption chuck (ESC) on which the wafer is placed is connected to the bias RF source to control the ion bombardment energy. In the inductively coupled plasma source discharge system, the output impedance has an inductive load coil and a capacitive load electrostatic adsorption chuck. The RF transmission line theory points out that when the characteristic impedance of the RF power supply is different from the output impedance, a standing wave effect will be generated in the entire RF loop (RF loop), that is, the reflection of a large RF power, resulting in power waste, plasma oscillation, and even possible safety accidents such as power supply damage. Therefore, it is necessary to add an impedance matcher between the RF power supply and the output load to automatically match the changing impedance of the load end, so as to achieve stable and efficient transmission of RF power and stable discharge of plasma.

[0003] During the operation of the impedance matcher, its matching speed and matching effect are strongly related to the discharge state of the plasma, directly determining the density, uniformity, stability, etc. of the plasma in the equipment chamber, which is crucial to the process results and processing efficiency of the machine. However, the existing scheme has many problems in actual operation; the more serious problem is that when dealing with some active special gases, its matching speed is slow, which has a great impact on the stability of the process results. Summary of the invention

[0004] The present invention provides an impedance matching method and a semiconductor device, which can realize fast, stable and efficient impedance matching and improve the stability of process results.

[0005] According to one aspect of the present invention, an impedance matching method is provided, wherein an impedance matching circuit comprises: a power supply, a matcher and a device chamber; the device chamber comprises a coil and a load impedance, the power supply is connected to an input end of the matcher, and an output end of the matcher is connected to the coil of the device chamber;

[0006] Impedance matching methods include:

[0007] Determining a preset amplitude and a preset phase at the input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the device chamber;

[0008] Acquire the amplitude and phase of the input end of the matching device;

[0009] When the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, determine the average value of the reflected power of the power supply in the current time period; wherein the first difference is the absolute value of the error range between the amplitude and the preset amplitude, and the second difference is the absolute value of the error range between the phase and the preset phase;

[0010] Determine that the average value of the reflected power of the power supply is less than the critical value of the reflected power failure;

[0011] Obtain all voltage values ​​or all current values ​​at the output end of the matcher in the current time period;

[0012] Determine a first risk number of times each voltage value is greater than a voltage threshold, or a second risk number of times each current value is greater than a current threshold;

[0013] When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and the phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0014] Optionally, after determining that the average value of the reflected power of the power supply is less than the reflected power bad critical value, the method further includes:

[0015] Get all reflected power of the power supply in the current time period;

[0016] Determine a third risk number of times that each reflected power is greater than a reflected power risk threshold;

[0017] It is determined that the third risk number is less than or equal to the preset risk number.

[0018] Optionally, the matcher includes a first variable capacitor and a second variable capacitor; after determining that the average value of the reflected power of the power supply is less than the reflected power bad critical value, the matcher further includes:

[0019] Get all reflected power of the power supply in the current time period;

[0020] Determine a third risk number of times that each reflected power is greater than a reflected power risk threshold;

[0021] When the third risk number is greater than the preset risk number, adjusting the first variable capacitor and the second variable capacitor of the matcher;

[0022] The amplitude and phase of the input end of the matching device after adjustment are determined so that the third risk number is less than or equal to the preset risk number.

[0023] Optionally, determining an average value of reflected power of the power supply in a current time period includes:

[0024] Get all reflected power of the power supply in the current time period;

[0025] Calculation is performed based on all acquired reflected powers to obtain an average value of the reflected powers of the power supply in the current time period.

[0026] Optionally, the matcher includes a first variable capacitor and a second variable capacitor; when the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, after determining the average value of the reflected power of the power supply in the current time period, the method further includes:

[0027] When the average value of the reflected power of the power supply is greater than or equal to the critical value of the reflected power failure, adjusting the first variable capacitor and the second variable capacitor of the matching device;

[0028] The amplitude and phase of the input end of the adjusted matching device are determined so that the average value of the reflected power of the power supply is less than the reflected power bad critical value.

[0029] Optionally, all voltage values ​​or all current values ​​at the output end of the matcher in the current time period are obtained, including:

[0030] Acquire all voltage values ​​at the output end of the matcher in the current time period through a voltage sensor; or,

[0031] All current values ​​at the output end of the matching device in the current time period are acquired through the current sensor.

[0032] Optionally, the matcher includes a first variable capacitor and a second variable capacitor; after determining a first risk number of times each voltage value is greater than a voltage threshold, or a second risk number of times each current value is greater than a current threshold, further comprising:

[0033] When the first risk number or the second risk number is greater than the preset risk number, adjusting the first variable capacitor and the second variable capacitor of the matcher;

[0034] The amplitude and phase of the input end of the matched device after adjustment are determined so that the first risk number or the second risk number is less than or equal to the preset risk number.

[0035] Optionally, the matcher includes a first variable capacitor and a second variable capacitor; after collecting the amplitude and phase of the input end of the matcher, the matcher further includes:

[0036] When the difference between the amplitude and the preset amplitude is greater than or equal to the first difference, and the difference between the phase and the preset phase is greater than or equal to the second difference, adjusting the first variable capacitor and the second variable capacitor of the matching device;

[0037] The adjusted amplitude and phase of the input end of the matcher are determined so that the difference between the adjusted amplitude and the preset amplitude is smaller than the first difference, and the difference between the adjusted phase and the preset phase is smaller than the second difference.

[0038] Optionally, the amplitude and phase of the input end of the matching device are collected, including:

[0039] The amplitude and phase of the input end of the matching device are collected by an amplitude phase sensor.

[0040] According to another aspect of the present invention, a semiconductor device is provided, which is matched by using the impedance matching method described in any embodiment of the present invention.

[0041] The impedance matching method provided by the technical solution of the embodiment of the present invention includes: determining a preset amplitude and a preset phase of the input end of the matcher, the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber; collecting the amplitude and phase of the input end of the matcher; when the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, determining the average value of the reflected power of the power supply in the current time period; wherein the first difference is the absolute value of the error range between the amplitude and the preset amplitude, and the second difference is the absolute value of the error range between the phase and the preset phase; determining that the average value of the reflected power of the power supply is less than the reflected power bad critical value; obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period; determining the first risk number of times each voltage value is greater than the voltage threshold, or the second risk number of times each current value is greater than the current threshold; when the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber. The amplitude and phase in the embodiment of the present invention are first compared with the preset amplitude and the preset phase, and the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference; then the reflected power of the power supply is judged, and the average value of the reflected power of the power supply is less than the critical value of the poor reflected power; finally, the current or voltage at the output end of the matcher is judged, and the risk number of the voltage or current is less than the preset risk number; when the three conditions are met at the same time, the amplitude and phase are determined so that the output impedance of the power supply matches the load impedance of the equipment chamber, and the amplitude and phase of the input end after matching are quickly set, so as to achieve fast, stable and efficient impedance matching, and improve the stability of the process results.

[0042] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 It is a topological diagram of an impedance matching circuit provided by an embodiment of the present invention.

[0045] Figure 2 It is a flow chart of an impedance matching method provided by an embodiment of the present invention.

[0046] Figure 3 It is an intermediate flow chart of an impedance matching method provided by an embodiment of the present invention.

[0047] Figure 4 This is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention.

[0048] Figure 5 yes Figure 2 A detailed flow chart included in S130.

[0049] Figure 6 This is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention.

[0050] Figure 7 This is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention.

[0051] Figure 8 This is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention.

[0052] Fig. 9 This is a flow chart of another impedance matching method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0053] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0054] It should be noted that the terms "first", "second", etc. in the present invention are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products, or devices.

[0055] An embodiment of the present invention provides an impedance matching method. Figure 1 is a topological diagram of an impedance matching circuit provided by an embodiment of the present invention, with reference to Figure 1 The impedance matching circuit includes: a power supply 01, a matcher 03 and a device chamber; the device chamber 05 includes a coil and a load impedance, the power supply 01 is connected to the input end of the matcher 03, and the output end of the matcher 03 is electrically connected to the coil of the device chamber 05.

[0056] The power supply 01 may be a radio frequency power supply; the matcher 03 further includes: a first sensor 02, an inductor, a first variable capacitor Cl, a second variable capacitor Ct, and a second sensor 04; the power supply 01 is connected to the first sensor 02, the first sensor 02 is connected to the input end of the inductor, the output end of the inductor is connected to the input end of the first variable capacitor Cl and the input end of the second variable capacitor Ct, the output end of the first variable capacitor Cl is grounded, the output end of the second variable capacitor Ct is connected to the second sensor 04, and the second sensor 04 is connected to the coil of the equipment chamber 05. The existing impedance matching method is that after the radio frequency power is input to the matcher 03, the first sensor 02 at the input end of the matcher 03 collects the amplitude (mag) and phase (phase), and according to the collected amplitude and phase, the motor is driven to rotate through an algorithm to change the capacitance values ​​of the first variable capacitor Cl and the second variable capacitor Ct in the matcher 03, so that the amplitude approaches 50Ω and the phase approaches 0, so that the input impedance of the input end of the matcher 03 is 50Ω, thereby matching the characteristic impedance 50Ω of the power supply 01, and realizing the effective transmission and feeding of the maximum power. The above matching method is applicable to the ignition of most common gases and can operate stably; common gases include argon (Ar) and oxygen (O2).

[0057] However, when the composition of the process gas changes, such as when dealing with some active special gases, active gases include carbon tetrafluoride (CF4) and hydrogen bromide (HBr) and the like; even when it is determined that efficient transmission is met through the amplitude and phase information and power feedback information in the first sensor 02, there may still be an unstable plasma state under a specific impedance state; for example, when some active special gases are injected into the equipment chamber 05, the gas flow rate and the pressure of the equipment chamber are adjusted; but since gases such as carbon tetrafluoride (CF4) and hydrogen bromide (HBr) are active and have strong adhesion, the reaction inside the equipment chamber 05 will be violent, the volatility will be strong and the fluctuation will be frequent; if only relying on the input end of the matcher 03 It is difficult for the first sensor 02 to capture and identify changes in the equipment chamber 05 in real time. If the capacitance value of the variable capacitor does not change in real time with the changes in the equipment chamber 05, a part of the output power of the power supply 01 cannot be absorbed by the equipment chamber 05, but is consumed in the transmission loop, that is, the reflected power is high; and the amplitude and phase that lead to high reflected power are risk matching points; the risk matching point is the point where effective transmission and feeding of maximum power cannot be achieved, which ultimately leads to instability of the process results; in the embodiment of the present invention, the risk matching point can be observed by the second sensor 04 at the output end of the matcher 03, thereby achieving fast, stable and efficient impedance matching and improving the stability of the process results.

[0058] Figure 2 is a flowchart of an impedance matching method provided by an embodiment of the present invention, refer to Figure 1 and Figure 2 , impedance matching methods include:

[0059] S110, determining a preset amplitude and a preset phase of the input end of the matcher 03; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0060] The preset amplitude is Mag1, and the preset phase is Phase1; the preset amplitude and preset phase that meet the matching of the output impedance of the power supply and the load impedance of the equipment chamber can be designed according to actual needs. The impedance matching circuit also includes a control module, which can determine the preset amplitude and preset phase of the input end of the matcher 03.

[0061] S120 , collecting the amplitude and phase of the input end of the matcher 03 .

[0062] Among them, the amplitude and phase of the input end of the matcher 03 are collected by the first sensor 02. At this time, the first sensor 02 can be an amplitude phase sensor; the control module is connected to the first sensor 02, and the amplitude and phase in the first sensor 02 after matching is completed are collected by the control module.

[0063] S130. When the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, determine the average value of the reflected power of the power supply in the current time period; wherein the first difference is the absolute value of the error range between the amplitude and the preset amplitude, and the second difference is the absolute value of the error range between the phase and the preset phase. Among them, the first difference is the absolute value of the error range between the amplitude of the collected matcher 03 input end and the preset amplitude, and the second difference is the absolute value of the error range between the phase of the collected matcher 03 input end and the preset phase. The error range between the amplitude of the collected matcher 03 input end and the preset amplitude and the error range between the phase of the collected matcher 03 input end and the preset phase can be set according to actual needs. The smaller the error range, the more accurate the result; the error range between the amplitude of the collected matcher 03 input end and the preset amplitude is -3Ω~3Ω, and the error range between the phase of the collected matcher 03 input end and the preset phase is -5°~5°; when the error range between the amplitude of the collected matcher 03 input end and the preset amplitude and the error range between the phase of the collected matcher 03 input end and the preset phase are 0, the amplitude is equal to the preset amplitude, and the phase is equal to the preset phase, the result is most accurate. When the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, it means that the amplitude and the phase make the output impedance of the power supply match the load impedance of the equipment chamber. However, if the composition of the process gas changes to an active gas, there may also be an unstable plasma state under a specific impedance state, resulting in instability in the process results. Therefore, further testing of the amplitude and phase is still required.

[0064] Specifically, the average value of the reflected power of the power supply in the current time period is determined. The current time period should be the time from when the output power of the RF power supply is collected until the RF power supply has no output power, that is, the time from when the amplitude and phase of the RF input end are collected until the amplitude and phase of the RF input end are not collected; the reflected power of the power supply can be monitored at each preset interval, and the preset interval time can be 1ms, 10ms, 100ms, etc. In theory, the smaller the preset interval time, the more accurate the monitoring accuracy and the more accurate the real-time monitoring. The power supply is provided with a detection module, which can monitor the reflected power of the power supply and obtain all the reflected powers of the power supply in the current time period. All the reflected powers can be [Ref1, Ref2, Ref3...Reft]; the average value of the reflected power of the power supply in the current time period is calculated based on all the obtained reflected powers, and the average value can be Ref.

[0065] S140: Determine whether the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

[0066] Among them, the critical value of reflected power failure is Refmin, which can be set according to the demand; judging the size of the average value Ref of the reflected power of the power supply and the critical value Refmin of reflected power failure is to identify whether the middle value of the reflected power in the current time period meets the requirements. If the average value of the reflected power of the power supply is greater than the critical value of reflected power failure, the amplitude and phase of the input end of the matcher 03 are considered as poor matching points, and the poor matching points are unqualified matching points; determining that the average value of the reflected power of the power supply is less than the critical value of reflected power failure indicates that the middle value of the reflected power in the current time period meets the requirements.

[0067] S150, acquiring all voltage values ​​or all current values ​​at the output end of the matcher 03 in the current time period.

[0068] Among them, the voltage value or current value of the output end of the matcher 03 can be monitored at each preset interval, and the preset interval time can be 1ms, 10ms, 100ms, etc. Theoretically, the smaller the preset interval time, the more accurate the monitoring accuracy is, and the real-time monitoring is more accurate; detection can be performed through the second sensor 04, and the second sensor 04 can be a voltage sensor or a current sensor. All voltage values ​​are obtained through the voltage sensor, and all current values ​​are obtained through the current sensor; all voltage values ​​or all current values ​​at the output end of the matcher 03 in the current time period are obtained. For example, all voltage values ​​are [V1, V2...Vt], and all current values ​​are [I1, I2...It].

[0069] S160: Determine a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold.

[0070] Among them, the voltage threshold is Vp, which can be set according to needs. By comparing each voltage value with the voltage threshold, if there is a voltage value greater than the voltage threshold, this voltage value is a risk matching point, and the first risk number is counted as once; the risk matching point is a matching point with risk, which cannot be equivalent to an unqualified matching point; if there are two voltage values ​​greater than the voltage threshold, the first risk number is counted as twice, and so on; or, the current threshold is Ip, which can be set according to needs. By comparing each current value with the current threshold, if there is a current value greater than the current threshold, this current value is a risk matching point, and the second risk number is counted as once; if there are two current values ​​greater than the current threshold, the second risk number is counted as twice, and so on.

[0071] S170: When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0072] Among them, the preset risk number can be set according to demand. When the first risk number or the second risk number is less than or equal to the preset risk number, it means that there is no point with large fluctuation in the current time period. At this time, the amplitude and phase of the input end of the matcher 03 are determined so that the output impedance of the power supply matches the load impedance of the equipment chamber. The amplitude and phase in the embodiment of the present invention are first compared with the preset amplitude and the preset phase. The difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference; then the power supply reflected power is judged, and the average value of the reflected power of the power supply is less than the critical value of the reflected power failure; finally, the current or voltage at the output end of the matcher 03 is judged, and the risk number of the voltage or current is less than the preset risk number; when the three conditions are met at the same time, the amplitude and phase are determined so that the output impedance of the power supply matches the load impedance of the equipment chamber, and the amplitude and phase of the input end after matching are quickly set, so as to achieve fast, stable and efficient impedance matching and improve the stability of the process results.

[0073] The impedance matching method provided by the technical solution of the embodiment of the present invention includes: determining a preset amplitude and a preset phase of the input end of the matcher, the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber; collecting the amplitude and phase of the input end of the matcher; when the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, determining the average value of the reflected power of the power supply in the current time period; wherein the first difference is the absolute value of the error range between the amplitude and the preset amplitude, and the second difference is the absolute value of the error range between the phase and the preset phase; determining that the average value of the reflected power of the power supply is less than the reflected power bad critical value; obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period; determining the first risk number of times each voltage value is greater than the voltage threshold, or the second risk number of times each current value is greater than the current threshold; when the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber. The amplitude and phase in the embodiment of the present invention are first compared with the preset amplitude and the preset phase, and the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference; then the reflected power of the power supply is judged, and the average value of the reflected power of the power supply is less than the critical value of the poor reflected power; finally, the current or voltage at the output end of the matcher is judged, and the risk number of the voltage or current is less than the preset risk number; when the three conditions are met at the same time, the amplitude and phase are determined so that the output impedance of the power supply matches the load impedance of the equipment chamber, and the amplitude and phase of the input end after matching are quickly set, so as to achieve fast, stable and efficient impedance matching, and improve the stability of the process results.

[0074] Optional, Figure 3 is an intermediate flow chart of an impedance matching method provided by an embodiment of the present invention, refer to Figure 3 After S140, determining that the average value of the reflected power of the power supply is less than the reflected power bad critical value, it also includes: S181, obtaining all reflected powers of the power supply in the current time period; S182, determining the third risk number that each reflected power is greater than the reflected power risk critical value; S183, determining that the third risk number is less than or equal to the preset risk number.

[0075] Specifically, an embodiment of the present invention provides a flow chart of an impedance matching method, including:

[0076] S110, determining a preset amplitude and a preset phase of an input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0077] S120, collecting the amplitude and phase of the input end of the matcher.

[0078] S130. When the difference between the amplitude and the preset amplitude is smaller than the first difference, and the difference between the phase and the preset phase is smaller than the second difference, determine the average value of the reflected power of the power supply in the current time period.

[0079] S140: Determine whether the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

[0080] S181. Obtain all reflected powers of the power supply in the current time period.

[0081] The reflected power of the power supply can be monitored at preset intervals, and the preset intervals can be 1ms, 10ms, 100ms, etc. Theoretically, the smaller the preset interval, the more accurate the monitoring accuracy and the more accurate the real-time monitoring. A detection module is provided in the power supply to monitor the reflected power of the power supply. The control module is connected to the power supply, and all reflected powers of the power supply monitored by the detection module in the current time period are obtained through the control module.

[0082] S182: Determine a third risk number of times that each reflected power is greater than a reflected power risk threshold.

[0083] Among them, the reflected power risk critical value is Ref1, which can be set according to needs; the reflected power risk critical value Ref1 is used to detect whether there is a large fluctuation in the reflected power value within a period of time, by comparing each reflected power with the reflected power risk critical value Ref1. If there is a reflected power greater than the reflected power risk critical value Ref1, then this reflected power is the risk matching point, and the third risk number is counted as one; if there are two reflected powers greater than the reflected power risk critical value Ref1, the third risk number is counted as two; and so on, so as to determine the third risk number.

[0084] S183: Determine whether the third risk number is less than or equal to the preset risk number.

[0085] By comparing the third risk number with the preset risk number, the third risk number is less than or equal to the preset risk number, and it is determined that the amplitude and phase of the input end of the matcher do not have a value with large reflected power fluctuation.

[0086] S150, obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period.

[0087] S160: Determine a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold.

[0088] S170: When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0089] Optional, reference Figure 1 , the matcher 03 includes a first variable capacitor C1 and a second variable capacitor Ct; Figure 4 is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention, refer to Figure 4 , after S140, determining that the average value of the reflected power of the power supply is less than the reflected power bad critical value, it also includes: S1801, obtaining all reflected powers of the power supply in the current time period; S1802, determining the third risk number that each reflected power is greater than the reflected power risk critical value; S1803, when the third risk number is greater than the preset risk number, adjusting the first variable capacitor and the second variable capacitor of the matcher; S1804, determining the amplitude and phase of the input end of the adjusted matcher so that the third risk number is less than or equal to the preset risk number.

[0090] Specifically, an embodiment of the present invention provides a flow chart of an impedance matching method, including:

[0091] S110, determining a preset amplitude and a preset phase of an input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0092] S120, collecting the amplitude and phase of the input end of the matcher.

[0093] S130. When the difference between the amplitude and the preset amplitude is smaller than the first difference, and the difference between the phase and the preset phase is smaller than the second difference, determine the average value of the reflected power of the power supply in the current time period.

[0094] S140: Determine whether the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

[0095] S1801. Obtain all reflected powers of the power supply in the current time period.

[0096] S1802: Determine a third risk number of times that each reflected power is greater than a reflected power risk threshold.

[0097] S1803: When the third risk number is greater than the preset risk number, adjust the first variable capacitor and the second variable capacitor of the matcher.

[0098] Among them, when the third risk number is greater than the preset risk number, the first variable capacitor and the second variable capacitor of the matcher are adjusted, and the algorithm drives the motor to rotate and change the capacitance value of the first variable capacitor Cl and the second variable capacitor Ct in the matcher 03, thereby adjusting the amplitude and phase of the input end of the matcher 03.

[0099] S1804. Determine the amplitude and phase of the input end of the adjusted matcher so that the third risk number is less than or equal to the preset risk number.

[0100] The amplitude and phase of the input end of the adjusted matcher are determined by the first sensor 02, so that the third risk number is less than or equal to the preset risk number.

[0101] S150, obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period.

[0102] S160: Determine a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold.

[0103] S170: When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0104] The difference between the above steps S181-S183 and S1801-S1804 lies in the two situations of whether the third risk number is greater than the preset risk number. S181-S183 is the situation where the third risk number is less than or equal to the preset risk number, and there is no need to adjust the matcher; S1801-S1804 is the situation where the third risk number is greater than the preset risk number, and the matcher needs to be adjusted.

[0105] Optionally, S130 may be refined based on the above embodiment. Figure 5 yes Figure 2 A detailed flow chart included in S130, refer to Figure 5 , S130, determining the average value of the reflected power of the power supply in the current time period, specifically including: S131, obtaining all reflected powers of the power supply in the current time period; S132, calculating according to all obtained reflected powers to obtain the average value of the reflected power of the power supply in the current time period.

[0106] Specifically, an embodiment of the present invention provides a flow chart of an impedance matching method, including:

[0107] S110, determining a preset amplitude and a preset phase of an input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0108] S120, collecting the amplitude and phase of the input end of the matcher.

[0109] S131. When the difference between the amplitude and the preset amplitude is smaller than the first difference, and the difference between the phase and the preset phase is smaller than the second difference, obtain all reflected powers of the power supply in the current time period.

[0110] The reflected power of the power supply can be monitored at preset intervals, and the preset intervals can be 1ms, 10ms, 100ms, etc. Theoretically, the smaller the preset interval, the more accurate the monitoring accuracy and the more accurate the real-time monitoring. The power supply is provided with a detection module, which can monitor the reflected power of the power supply and obtain all reflected powers of the power supply in the current time period. All reflected powers can be [Ref1, Ref2, Ref3...Reft].

[0111] S132: Calculate based on all acquired reflected powers to obtain an average value of the reflected powers of the power supplies in the current time period.

[0112] The average value of all reflected powers is taken to obtain the average value of the reflected power of the power supply in the current time period.

[0113] S140: Determine whether the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

[0114] S150, obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period.

[0115] S160: Determine a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold.

[0116] S170: When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0117] Optionally, the matcher includes a first variable capacitor and a second variable capacitor; Figure 6 is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention, refer to Figure 6 , S130, when the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, after determining the average value of the reflected power of the power supply in the current time period, it also includes: S1401, when the average value of the reflected power of the power supply is greater than or equal to the reflected power bad critical value, adjusting the first variable capacitor and the second variable capacitor of the matcher; S1402, determining the amplitude and phase of the input end of the adjusted matcher so that the average value of the reflected power of the power supply is less than the reflected power bad critical value.

[0118] Specifically, an embodiment of the present invention provides a flow chart of an impedance matching method, including:

[0119] S110, determining a preset amplitude and a preset phase of an input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0120] S120, collecting the amplitude and phase of the input end of the matcher.

[0121] S130. When the difference between the amplitude and the preset amplitude is smaller than the first difference, and the difference between the phase and the preset phase is smaller than the second difference, determine the average value of the reflected power of the power supply in the current time period.

[0122] S140: Determine whether the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

[0123] S1401. When the average value of the reflected power of the power supply is greater than or equal to the critical value of the reflected power failure, adjust the first variable capacitor and the second variable capacitor of the matching device.

[0124] In which, when the average value of the reflected power of the power supply is greater than or equal to the critical value of the reflected power failure, the first variable capacitor and the second variable capacitor of the matcher are adjusted, and the algorithm drives the motor to rotate to change the capacitance value of the first variable capacitor and the second variable capacitor in the matcher, thereby adjusting the amplitude and phase of the input end of the matcher.

[0125] S1402, determining the amplitude and phase of the input end of the matched device after adjustment so that the average value of the reflected power of the power supply is less than the critical value of the reflected power failure.

[0126] The amplitude and phase of the input end of the matched device after adjustment are determined by the first sensor 02, so that the average value of the reflected power of the power supply is less than the critical value of the reflected power failure.

[0127] S150, obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period.

[0128] S160: Determine a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold.

[0129] S170: When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0130] Optionally, all voltage values ​​or all current values ​​at the output end of the matcher in the current time period are obtained, including:

[0131] All voltage values ​​at the output end of the matcher in the current time period are acquired through a voltage sensor; or all current values ​​at the output end of the matcher in the current time period are acquired through a current sensor.

[0132] The control module is connected to a voltage sensor, and all voltage values ​​at the output end of the matcher in the current time period are obtained through the voltage sensor; or the control module is connected to a current sensor, and all current values ​​at the output end of the matcher in the current time period are obtained through the current sensor.

[0133] Optionally, the matcher includes a first variable capacitor and a second variable capacitor; Figure 7 is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention, refer to Figure 7, S160, after determining the first risk number that each voltage value is greater than the voltage threshold, or the second risk number that each current value is greater than the current threshold, it also includes: S161, when the first risk number or the second risk number is greater than the preset risk number, adjusting the first variable capacitor and the second variable capacitor of the matcher; S162, determining the amplitude and phase of the input end of the adjusted matcher so that the first risk number or the second risk number is less than or equal to the preset risk number.

[0134] Specifically, an embodiment of the present invention provides a flow chart of an impedance matching method, including:

[0135] S110, determining a preset amplitude and a preset phase of an input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0136] S120, collecting the amplitude and phase of the input end of the matcher.

[0137] S130. When the difference between the amplitude and the preset amplitude is smaller than the first difference, and the difference between the phase and the preset phase is smaller than the second difference, determine the average value of the reflected power of the power supply in the current time period.

[0138] S140: Determine whether the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

[0139] S150, obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period.

[0140] S160: Determine a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold.

[0141] S161. When the first risk number or the second risk number is greater than a preset risk number, adjust the first variable capacitor and the second variable capacitor of the matcher.

[0142] Among them, when the first risk number or the second risk number is greater than the preset risk number, the first variable capacitor and the second variable capacitor of the matcher are adjusted, and the algorithm drives the motor to rotate to change the capacitance value of the first variable capacitor and the second variable capacitor in the matcher, thereby adjusting the amplitude and phase of the input end of the matcher.

[0143] S162: Determine the amplitude and phase of the input end of the adjusted matcher so that the first risk number or the second risk number is less than or equal to the preset risk number.

[0144] The amplitude and phase of the input end of the adjusted matcher are determined by the first sensor 02, so that the first risk number or the second risk number is less than or equal to the preset risk number.

[0145] S170: When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0146] Optionally, the matcher includes a first variable capacitor and a second variable capacitor; Figure 8 is an intermediate flow chart of another impedance matching method provided by an embodiment of the present invention, refer to Figure 8 , after collecting the amplitude and phase of the input end of the matcher at S120, it also includes: S121, when the difference between the amplitude and the preset amplitude is greater than or equal to the first difference, and the difference between the phase and the preset phase is greater than or equal to the second difference, adjusting the first variable capacitor and the second variable capacitor of the matcher; S122, determining the amplitude and phase of the input end of the matcher after adjustment, so that the difference between the adjusted amplitude and the preset amplitude is less than the first difference, and the difference between the adjusted phase and the preset phase is less than the second difference.

[0147] Specifically, an embodiment of the present invention provides a flow chart of an impedance matching method, including:

[0148] S110, determining a preset amplitude and a preset phase of an input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0149] S120, collecting the amplitude and phase of the input end of the matcher. Optionally, collecting the amplitude and phase of the input end of the matcher includes: collecting the amplitude and phase of the input end of the matcher through an amplitude phase sensor. The first sensor 02 is an amplitude phase sensor.

[0150] S121. When the difference between the amplitude and the preset amplitude is greater than or equal to the first difference, and the difference between the phase and the preset phase is greater than or equal to the second difference, adjust the first variable capacitor and the second variable capacitor of the matcher.

[0151] In which, when the difference between the amplitude and the preset amplitude is greater than or equal to the first difference, and the difference between the phase and the preset phase is greater than or equal to the second difference, the first variable capacitor and the second variable capacitor of the matcher are adjusted, and the algorithm drives the motor to rotate to change the capacitance value of the first variable capacitor and the second variable capacitor in the matcher, thereby adjusting the amplitude and phase of the input end of the matcher.

[0152] S122, determining the adjusted amplitude and phase of the input end of the matcher so that the difference between the adjusted amplitude and the preset amplitude is smaller than the first difference, and the difference between the adjusted phase and the preset phase is smaller than the second difference.

[0153] The first sensor 02 is used to determine the adjusted amplitude and phase of the input end of the matcher, so that the difference between the adjusted amplitude and the preset amplitude is smaller than the first difference, and the difference between the adjusted phase and the preset phase is smaller than the second difference.

[0154] S130. When the difference between the amplitude and the preset amplitude is smaller than the first difference, and the difference between the phase and the preset phase is smaller than the second difference, determine the average value of the reflected power of the power supply in the current time period.

[0155] S140: Determine whether the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

[0156] S150, obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period.

[0157] S160: Determine a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold.

[0158] S170: When the first risk number or the second risk number is less than or equal to the preset risk number, the amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber.

[0159] An embodiment of the present invention provides an impedance matching method. Fig. 9 is a flowchart of another impedance matching method provided by an embodiment of the present invention, referring to Fig. 9 , the impedance matching method specifically includes:

[0160] S1: First, determine whether the difference between the amplitude Mag and the preset amplitude Mag1 is less than the first difference △Mag, and the difference between the phase Phase and the preset phase Phase1 is less than the second difference △Phase; illustratively, determine whether Mag is close to Mag1, and whether Phase is close to Phase1, if the two are approximately equal; if the difference between the amplitude Mag and the preset amplitude Mag1 is greater than or equal to the first difference △Mag, and the difference between the phase Phase and the preset phase Phase1 is greater than or equal to the second difference △Phase, it is necessary to reset the amplitude Mag and the phase Phase so that the difference between the amplitude Mag and the preset amplitude Mag1 is less than the first difference △Mag, and the difference between the phase Phase and the preset phase Phase1 is less than the second difference △Phase.

[0161] S2: If the difference between the amplitude Mag and the preset amplitude Mag1 is less than the first difference △Mag, and the difference between the phase Phase and the preset phase Phase1 is less than the second difference △Phase, then it is determined that the average value Ref of the reflected power of the power supply is less than the critical value Refmin of poor reflected power, that is, Ref < Refmin; if Ref ≥ Refmin, then this point is determined as a poor matching point, and the first variable capacitor and the second variable capacitor of the matcher are adjusted, and the amplitude Mag is reset to Mag2 and the Phase is reset to Phase2 so that Ref < Refmin.

[0162] S3: If Ref < Refmin, count all the reflected powers [Ref1, Ref2... Reft] of the power supply reflected power in the current time period, and set any value in [Ref1, Ref2... Reft] > the critical value Refp1 of the reflected power risk, which is a risk matching point, and count the third risk times T3 of each reflected power greater than the critical value of the reflected power risk in the current time period.

[0163] S4: If the third risk times > the preset risk times, adjust the first variable capacitor and the second variable capacitor of the matcher, and reset the amplitude Mag to Mag3 and the Phase to Phase3 so that the third risk times ≤ the preset risk times.

[0164] S5: If the third risk times ≤ the preset risk times, and any value in all voltage values [V1, V2... Vt] > the voltage threshold Vp, or any value in all current values [I1, I2... It] > the current threshold Ip, then this matching position is considered a risk matching point, and count the first risk times of each voltage value greater than the voltage threshold, or the second risk times of each current value greater than the current threshold.

[0165] S6: If the first risk times or the second risk times ≤ the preset risk times, the current amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber. If the first risk times or the second risk times > the preset risk times, adjust the first variable capacitor and the second variable capacitor of the matcher, and reset the amplitude Mag to Mag4 and the Phase to Phase4 so that the first risk times or the second risk times ≤ the preset risk times. The current amplitude and phase make the output impedance of the power supply match the load impedance of the equipment chamber. Through the judgment of the three conditions, it is determined that the target matching value is a fast, stable and efficient matching target value.

[0166] The embodiment of the present invention can compare and determine the process menus of different special gases through the host computer algorithm, and quickly set the input amplitude and phase target values ​​after matching, thereby achieving a fast, stable and efficient matching window, and can broaden the process application window of the machine and improve the stability of the machine process; and can meet customers' requirements for more process development and provide efficient and reliable impedance matching solutions for various processes.

[0167] An embodiment of the present invention provides a semiconductor device based on the above embodiment, and uses the impedance matching method described in any embodiment of the present invention to perform matching.

[0168] The semiconductor device provided by the embodiment of the present invention has the same beneficial effects as the impedance matching method described in any embodiment of the present invention.

[0169] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0170] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An impedance matching method, characterized in that: The impedance matching circuit comprises: a power supply, a matcher and a device chamber; the device chamber comprises a coil and a load impedance, the power supply is connected to the input end of the matcher, and the output end of the matcher is connected to the coil of the device chamber; The impedance matching method comprises: Determining a preset amplitude and a preset phase of an input end of the matcher; the preset amplitude and the preset phase make the output impedance of the power supply match the load impedance of the device chamber; Collecting the amplitude and phase of the input end of the matcher; When the difference between the amplitude and the preset amplitude is less than a first difference, and the difference between the phase and the preset phase is less than a second difference, determining the average value of the reflected power of the power supply in the current time period; wherein the first difference is the absolute value of the error range between the amplitude and the preset amplitude, and the second difference is the absolute value of the error range between the phase and the preset phase; Determining that the average value of the reflected power of the power supply is less than a critical value of a poor reflected power; Acquire all voltage values ​​or all current values ​​at the output end of the matcher in a current time period; Determine a first risk number of times each voltage value is greater than a voltage threshold, or a second risk number of times each current value is greater than a current threshold; When the first risk number or the second risk number is less than or equal to a preset risk number, the amplitude and the phase make the output impedance of the power supply match the load impedance of the equipment chamber.

2. The impedance matching method according to claim 1, characterized in that: After determining that the average value of the reflected power of the power source is less than the reflected power bad critical value, the method further includes: Acquire all reflected powers of the power supply in the current time period; Determine a third risk number of times that each of the reflected powers is greater than a reflected power risk threshold; It is determined that the third risk number is less than or equal to a preset risk number.

3. The impedance matching method according to claim 1, characterized in that: The matcher includes a first variable capacitor and a second variable capacitor; after determining that the average value of the reflected power of the power supply is less than the reflected power bad critical value, it also includes: Acquire all reflected powers of the power supply in the current time period; Determine a third risk number of times that each of the reflected powers is greater than a reflected power risk threshold; When the third risk number is greater than the preset risk number, adjusting the first variable capacitor and the second variable capacitor of the matcher; The adjusted amplitude and phase of the input end of the matcher are determined so that the third risk number is less than or equal to a preset risk number.

4. The impedance matching method according to claim 1, characterized in that: Determining an average value of the reflected power of the power source in a current time period, comprising: Acquire all reflected powers of the power supply in the current time period; Calculation is performed based on all acquired reflected powers to obtain an average value of the reflected power of the power supply in the current time period.

5. The impedance matching method according to claim 1, characterized in that: The matcher includes a first variable capacitor and a second variable capacitor; when the difference between the amplitude and the preset amplitude is less than the first difference, and the difference between the phase and the preset phase is less than the second difference, after determining the average value of the reflected power of the power supply in the current time period, the matcher further includes: When the average value of the reflected power of the power source is greater than or equal to the critical value of the reflected power failure, adjusting the first variable capacitor and the second variable capacitor of the matching device; The adjusted amplitude and phase of the input end of the matcher are determined so that the average value of the reflected power of the power supply is less than a critical value of the reflected power failure.

6. The impedance matching method according to claim 1, characterized in that: Obtaining all voltage values ​​or all current values ​​at the output end of the matcher in the current time period, including: Acquire all voltage values ​​of the output terminal of the matcher in the current time period through a voltage sensor; or, All current values ​​at the output end of the matcher in the current time period are acquired through the current sensor.

7. The impedance matching method according to claim 1, characterized in that: The matcher includes a first variable capacitor and a second variable capacitor; After determining a first risk number of times that each voltage value is greater than a voltage threshold, or a second risk number of times that each current value is greater than a current threshold, the method further includes: When the first risk number or the second risk number is greater than a preset risk number, adjusting the first variable capacitor and the second variable capacitor of the matcher; The adjusted amplitude and phase of the input end of the matcher are determined so that the first risk number or the second risk number is less than or equal to a preset risk number.

8. The impedance matching method according to claim 1, characterized in that: The matcher includes a first variable capacitor and a second variable capacitor; After collecting the amplitude and phase of the input end of the matcher, the method further includes: When the difference between the amplitude and the preset amplitude is greater than or equal to the first difference, and the difference between the phase and the preset phase is greater than or equal to the second difference, adjusting the first variable capacitor and the second variable capacitor of the matcher; The adjusted amplitude and phase of the input end of the matcher are determined so that the difference between the adjusted amplitude and the preset amplitude is smaller than the first difference, and the difference between the adjusted phase and the preset phase is smaller than the second difference.

9. The impedance matching method according to claim 1, characterized in that: Acquiring the amplitude and phase of the input end of the matcher, including: The amplitude and phase of the input end of the matcher are collected by an amplitude and phase sensor.

10. A semiconductor device, characterized in that: The impedance matching is performed using the impedance matching method described in any one of claims 1 to 9.

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