Device and method for adjusting phase delay of bias generator in dual-cavity system

Abstract

The invention relates to an apparatus and a method for adjusting phase delay between bias generators in a dual-cavity system, the dual-cavity system comprising: a first cavity device comprising: a first cavity comprising a first chuck and a first bias generator connected to the first chuck; and a second cavity arrangement comprising: a second cavity comprising a second chuck and a second bias generator connected to the second chuck, where the apparatus is configured to adjust a current phase delay of the first bias generator and the second bias generator to communicate radio frequency signals in the first cavity and the second cavity. According to the scheme, the phase delay degree between the bias generators can be effectively changed, and the optimal region of the phase delay degree of the bias generators in a double-cavity system is standardized, so that the problems that plasmas cannot be completely dissociated and radio frequency crosstalk occurs are effectively solved, and the etching rate of a wafer is kept uniform.

Description

Technical Field

[0001] The present invention relates to semiconductor manufacturing technology, and in particular to a device and method for adjusting the phase delay of a bias generator in a dual-cavity system, the dual-cavity system, and a plasma chamber. Background Art

[0002] The COP (cell open process) of a dry etch producer (a device name) requires the removal of oxide films (Oxide films) thicker than 14k (μm) to provide uniform performance downstream. However, due to the shared pump system in the dual-chamber design of this workstation, wafers processed by the dual chucks in the dual chambers are subject to mirror-symmetrical non-uniformity caused by RF crosstalk, and significant plasma chamber variation occurs throughout the entire process.

[0003] Typically, semiconductor equipment workstations do not control the default phase delay of the random bias generator in the chuck within the plasma chamber. However, due to the randomness of the current phase in the dual chambers, the bias voltage applied to the two chambers in the dual chamber system may be insufficient, resulting in incomplete dissociation of the plasma in the two chambers, causing radio frequency crosstalk. This directly leads to poor uniformity in the etching rate (or speed) of the wafers clamped by the two chucks, resulting in a reduced yield in the wafer processing process.

[0004] Therefore, the prior art requires a solution for eliminating radio frequency interference in a dual-cavity system, and the dual-cavity system is capable of effectively adjusting the current phase delay between the middle chucks.

[0005] The foregoing is only intended to help understand the background of the embodiments of the present invention, and is not intended to mean that the embodiments of the present invention fall within the scope of the relevant prior art known to those skilled in the art. Summary of the Invention

[0006] The present invention relates to an apparatus and method for adjusting the phase delay between bias generators in a dual-chamber system, a dual-chamber system, and a plasma chamber. By arranging bias generators in the dual chambers and tuning the phase delay of the bias generator currents, the present invention can improve radio frequency crosstalk in plasma chambers of models such as the AMAT Producer model.

[0007] A first aspect of the present invention provides a device for adjusting the phase delay between bias generators in a dual-cavity system, the dual-cavity system comprising: a first cavity device comprising: a first cavity comprising a first chuck and a first bias generator connected to the first chuck; a second cavity device comprising: a second cavity comprising a second chuck and a second bias generator connected to the second chuck, wherein the device is configured to: adjust the current phase delay between the first bias generator and the second bias generator to transmit a radio frequency signal in the first cavity and the second cavity.

[0008] A second aspect of the present invention provides a method for adjusting the phase delay of a bias generator in a dual-cavity system. The dual-cavity system includes: a first cavity device, including: a first cavity including a first chuck and a first bias generator connected to the first chuck; a second cavity device, including: a second cavity including a second chuck and a second bias generator connected to the second chuck. The method includes: adjusting the current phase delay of the first bias generator and the second bias generator to transmit a radio frequency signal in the first cavity and the second cavity.

[0009] A third aspect of the present invention provides a dual-cavity system, which includes the above-mentioned device for adjusting the phase delay of the bias generator in the dual-cavity system, or uses the above-mentioned method for adjusting the phase delay of the bias generator in the dual-cavity system.

[0010] A fourth aspect of the present invention provides a plasma chamber, comprising the dual-chamber system described above.

[0011] According to the scheme of adjusting the phase delay of the bias generator of the cavity device in the dual-cavity system of the present invention, the degree of phase delay in the bias generator in the dual-cavity system of the bias generator can be effectively changed. In addition, the present invention designs a fixed DOE (Design of Experiment) to standardize the optimal area of ​​the phase delay of the bias generator of the cavity device in the dual-cavity system of this model, thereby effectively avoiding the problems of incomplete dissociation of plasma and radio frequency crosstalk, and making the etching rate of the chip more uniform.

[0012] The advantages of the embodiments of the present invention are not limited to the above advantages. Through the following description, those skilled in the art can clearly understand other advantages not described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 FIG. 4 shows a schematic diagram of a dual-cavity system according to an embodiment of the present invention.

[0014] Figure 2 FIG2 shows a working principle diagram of a dual-cavity system according to an embodiment of the present invention when the phase delay between the chucks is 180 degrees.

[0015] Figure 3 FIG2 shows a working principle diagram of a dual-cavity system according to an embodiment of the present invention when the phase delay between the chucks is 45 degrees.

[0016] Figure 4 A diagram showing a relationship between a DC bias voltage and a current phase delay of a first bias generator in a first cavity device and a second bias generator in a second cavity device according to an embodiment of the present invention is shown.

[0017] Figure 5 A graph showing the relationship between wafer etch rates at the first and second chucks and the current phase delays of the first bias generator in the first chamber device and the second bias generator in the second chamber device when they are out of phase is shown according to an embodiment of the present invention.

[0018] Figure 6 A relationship diagram is shown between wafer etching rates at the first and second chucks and current phase delays of a first bias generator in a first chamber device and a second bias generator in a second chamber device when they are in the same direction according to an embodiment of the present invention.

[0019] Figure 7 A relationship diagram of wafer etching rate, etching radius, and current phase delay of a first bias generator in a first cavity device and a second bias generator in a second cavity device at a first chuck and a second chuck according to an embodiment of the present invention is shown.

[0020] Figure 8 A diagram illustrating a tuning region of current phase delays of a first bias generator in a first cavity device and a second bias generator in a second cavity device according to an embodiment of the present invention is shown.

[0021] Figure 9 A diagram showing the relationship between the DC bias voltage, relative time, and the current phase delay region of a first bias generator in a first cavity device and a second bias generator in a second cavity device according to an embodiment of the present invention is shown.

[0022] Figure 10 A relationship diagram of wafer etching rate, etching radius, and current phase delay region of a first bias generator in a first chamber device and a second bias generator in a second chamber device at a first chuck and a second chuck according to an exemplary embodiment of the present invention is shown.

[0023] Figure 11 A relationship diagram showing the left and right etching rate difference of a wafer, the current phase delay region of a first bias generator in a first chamber device and a second bias generator in a second chamber device, and the DC bias voltage according to an embodiment of the present invention is shown.

[0024] The figures are not drawn to scale. Wherever possible, the same reference numbers will be used throughout the drawings and accompanying written description to refer to the same or like parts. DETAILED DESCRIPTION

[0025] Although the following detailed description contains many specific details for purposes of illustration, those skilled in the art will appreciate that many variations and modifications to the following details may be made and are considered to be included herein.

[0026] Therefore, the following examples are set forth without any loss of generality of any of the claims and without limiting any of the claims. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0027] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a layer" includes a plurality of such layers.

[0028] It will be understood that when a component is referred to as being “connected to” or “coupled to” another component, it can be directly connected to or coupled to the other component or intervening components may exist. Conversely, when a component is referred to as being “directly connected to” or “directly coupled to” another component, there are no intervening components.

[0029] As used herein, singular forms are intended to include plural forms as well, unless the context clearly indicates otherwise.

[0030] It should be further understood that the terms "including" or "having" when used in this specification specify the existence of the stated features, numbers, steps, operations, components, elements, or a combination thereof, but they do not exclude the existence or addition of one or more other features, numbers, steps, operations, components, elements, or a combination thereof.

[0031] Hereinafter, embodiments disclosed in this specification are described with reference to the accompanying drawings, in which the same reference numerals are assigned to refer to the same or similar components and redundant descriptions thereof are omitted.

[0032] The plasma chamber in this model includes a dual-chamber system. In this dual-chamber system, the phase delay of the current flowing through the two chambers is a key factor in RF crosstalk. Due to the different degrees of current phase delay, the voltage in the two chambers fluctuates. When the voltage is low, the low-voltage recipe setting will enhance plasma ion bombardment, which will exacerbate the micro-trench problem. In addition, low voltage will reduce the etch rate of oxides or oxide films, resulting in higher costs in wafer processing. The high-source recipe setting will increase chemical etching, thereby reducing the selectivity of etching oxide and nitride films.

[0033] Furthermore, new recipes require qualification and control through EOL (end of line) data, which consumes additional time and human resources. Furthermore, while new recipe adjustments cannot account for chamber-to-chamber variations, the phase delay of the bias generator in the cavity device can be adjusted at the chamber level.

[0034] Thus, the present invention provides a solution for adjusting the phase delay between bias generators in a dual cavity system.

[0035] Figure 1 FIG. 4 shows a schematic diagram of a dual-cavity system according to an embodiment of the present invention.

[0036] like Figure 1 As shown, the dual-cavity system of the present invention includes: a first cavity device, including: a first cavity including a first chuck and a first bias generator connected to the first chuck; a second cavity device, including: a second cavity including a second chuck and a second bias generator connected to the second chuck. The first bias generator is connected to the second bias generator via a cable. The dual-cavity system also includes a device for adjusting the phase delay between the bias generators in the dual-cavity system (i.e. Figure 1 The first and second cavities comprise a dual-cavity system of the present invention, which is located in a plasma chamber.

[0037] According to one or more embodiments of the present invention, the first bias generator sends an initial radio frequency signal to the second bias generator through a cable.

[0038] According to one or more embodiments of the present invention, the regulating device of the present invention may be a physical controller provided in the dual-chamber system, or provided in the dual-chamber system or model in the form of software, hardware or firmware.

[0039] Figure 2FIG2 shows a working principle diagram of a dual-cavity system according to an embodiment of the present invention when the phase delay between the bias generators is 180 degrees.

[0040] like Figure 2 As shown, CEX is a cable connecting the first bias generator of the first cavity device and the second bias generator of the second cavity device to maintain communication. The phase delay between the first cavity device and the second cavity device is the change in the phase difference between the first bias generator and the second bias generator. The first bias generator will output an initial radio frequency (RF) signal to the second bias generator through the CEX cable, and the first bias generator and the second bias generator will maintain a certain phase delay to transmit the RF signal in the two cavities. The first chuck and the second chuck can be electrostatic chucks ESC (or electrostatic suction cups) for clamping the wafer. The gas is delivered into the dual cavity of the plasma chamber by the turbocharger through the airflow control invention.

[0041] According to one or more embodiments of the present invention, the dual-chamber "pumping effect" problem in semiconductor equipment models is mainly driven by the dual-chamber system design of the model. In the semiconductor equipment model, the pump system is shared, and the two cavities are not completely isolated, which allows lateral electromagnetic fields to interact and plasma crosstalk is likely to occur.

[0042] like Figure 2 As shown, when the phase of the current applied from the input CEX IN of the CEX cable to the RF output of the first electrostatic chuck remains out of phase (i.e., 180 degrees), this may cause the phase delay from CEX IN of the CEX cable (connected to the first bias generator) to the cable CEX OUT (connected to the second bias generator) to be 180 degrees (out of phase), which will generate out-of-phase RF signals between the two cavities of the plasma chamber, and cannot provide uniform plasma distribution between the two cavities, which will result in a low DC bias voltage (<1600V) in the two cavities, resulting in plasma instability and failure to dissociate, thereby causing RF crosstalk and resulting in uneven etching rate between the two chucks.

[0043] Figure 3 FIG2 shows a working principle diagram of a dual-cavity system according to an embodiment of the present invention when the phase delay between the chucks is 45 degrees.

[0044] like Figure 3 As shown, the phase delay from CEX IN to RF output is corrected (maintained at 45 degrees), that is, after the phase delay is adjusted to be in phase (45 degrees), the phase delay from CEX IN to CEX OUT is corrected from Figure 2The phase delay of 180 degrees is changed to the new corrected phase delay of 45 degrees, resulting in uniform distribution of plasma in the plasma chamber, and no problem of non-dissociation occurs. At this time, the plasma generated by the dual-chamber system is not easily interfered with, thereby eliminating the RF crosstalk problem. The DC bias voltage in the dual-chamber system returns to the single-chamber processing performance (>1600V), and the etch rate between the dual chucks is also kept uniform.

[0045] According to one or more embodiments of the present invention, the current phase delay between the first bias generator and the second bias generator is related to the difference between the etching rate at the first chuck and the etching rate at the second chuck, and the current phase delay between the first bias generator and the second bias generator is related to the DC bias voltage in the plasma chamber in which the dual-chamber system is located.

[0046] Figure 4 A diagram showing a relationship between a DC bias voltage and a current phase delay of a first bias generator in a first cavity device and a second bias generator in a second cavity device according to an embodiment of the present invention is shown.

[0047] from Figure 4 It can be seen that when the current phase delay between the first bias generator and the second bias generator is 180 degrees (out of phase), the DC bias voltage generated in the dual-cavity system is less than 1600 V (rated operating voltage), and when the current phase delay between the first bias generator and the second bias generator is 45 degrees (in phase) and zero degrees, the DC bias voltage generated in the cavity of the dual-cavity system is greater than 1600 V (rated operating voltage), so that the plasma can be evenly distributed and the etching rate can also be kept uniform.

[0048] Figure 5 A graph showing the relationship between wafer etch rates at the first and second chucks and the current phase delays of the first bias generator in the first chamber device and the second bias generator in the second chamber device when they are out of phase is shown according to an embodiment of the present invention. Figure 6 A relationship diagram is shown between wafer etching rates at the first and second chucks and current phase delays of a first bias generator in a first chamber device and a second bias generator in a second chamber device when they are in the same direction according to an embodiment of the present invention.

[0049] like Figure 5 and Figure 6 As shown in the top view and the top view in FIG, when the current phase delay of the first bias generator and the second bias generator is out of phase (180 degrees), the etching rates at the first chuck and the second chuck are obviously uneven. When the current phase delay of the first bias generator and the second bias generator is in phase (45 degrees), the etching rates at the first chuck and the second chuck are uniform. Figure 5 and Figure 6In the formula, mean represents the average value of 49 measurement points, 3-sigma represents the value of three times the standard deviation of the 49 points on both sides, and range represents the range of the difference between the maximum and minimum values ​​of the 49 points on both sides.

[0050] Figure 7 A relationship diagram of wafer etching rate, etching radius, and current phase delay of a first bias generator in a first cavity device and a second bias generator in a second cavity device at a first chuck and a second chuck according to an embodiment of the present invention is shown.

[0051] like Figure 7 As shown in FIG, when the current phase delay between the first bias generator and the second bias generator is maintained at 180 degrees, the DC bias voltage of the plasma chamber is low (<1600V rated voltage), which means that the plasma is unstable and crosstalk occurs between the two chambers. The etch rate (ER) of the wafer will be uneven, and the etching rate L on the left side of the wafer - the etching rate R on the right side of the wafer will be relatively large (reaching When the current phase delay between the first bias generator and the second bias generator is changed to 45 degrees, the DC bias voltage of the plasma chamber is higher than 1600V, which means that the plasma is completely dissociated in each chuck, and the etch rate (ER) of the wafer will be uniform. At this time, |Etch rate L on the left side of the wafer - Etch rate R on the right side of the wafer| (i.e., |LR|) is Close to zero, indicating that the etching rate of the wafer is uniform.

[0052] According to one or more embodiments of the present invention, tuning the current phase delay of the first bias generator and the second bias generator to 45 degrees fixes the plasma crosstalk problem in the dual-cavity system.

[0053] According to one or more embodiments of the present invention, the current phase delay of the first bias generator and the second bias generator can be adjusted according to the region, and a tuning knob can be set to tune the phase delay of the first bias generator and the second bias generator. According to one or more embodiments of the present invention, the adjustment result of the current phase delay of the first bias generator and the second bias generator can be displayed in a visual manner.

[0054] Figure 8 A diagram illustrating a tuning region of current phase delays of a first bias generator in a first cavity device and a second bias generator in a second cavity device according to an embodiment of the present invention is shown.

[0055] like Figure 8As shown, the regions in which the current phase delay of the first bias generator and the second bias generator can be tuned are: -45 degrees (or 315 degrees) to 90 degrees, 90 degrees to 180 degrees and 225 degrees to 315 degrees (-45 degrees), and 180 degrees to 225 degrees.

[0056] The current phase delay region of the first bias generator and the second bias generator that can be tuned is defined as follows:

[0057] Safe Area( Figure 8 Green area in the middle): 315 degrees to 90 degrees;

[0058] Tuning Area( Figure 8 The yellow area in the middle): 90 degrees to 180 degrees and 225 degrees to 315 degrees;

[0059] The poor area is ( Figure 8 The red area in the middle): 180 degrees to 225 degrees;

[0060] According to one or more embodiments of the present invention, the current phase delay between the first bias generator and the second bias generator can be adjusted to a safe region or tuning region. When tuned to the safe phase delay region, the dual-chamber system achieves optimal performance, i.e., plasma uniformity, uniform etch rate, and no RF crosstalk. The poor region is a tuning region that is not recommended or advised, as RF crosstalk may occur in this region and tuning to this region is therefore not recommended or advised.

[0061] Figure 9 A diagram showing the relationship between the DC bias voltage, relative time, and the current phase delay region of a first bias generator in a first cavity device and a second bias generator in a second cavity device according to an embodiment of the present invention is shown. Figure 10 A relationship diagram of wafer etching rate, etching radius, and current phase delay region of a first bias generator in a first chamber device and a second bias generator in a second chamber device at a first chuck and a second chuck according to an exemplary embodiment of the present invention is shown. Figure 11 A relationship diagram showing the left and right etching rate difference of a wafer, the current phase delay region of a first bias generator in a first chamber device and a second bias generator in a second chamber device, and the DC bias voltage according to an embodiment of the present invention is shown.

[0062] like Figures 9 to 11 As shown, the best phase area is -45 degrees (or 315 degrees) to 90 degrees, then tends to medium performance 90 degrees to 180 degrees and 225 degrees to 315 degrees (-45 degrees), and the poor performance area is 180 degrees to 225 degrees.

[0063] According to one or more embodiments of the present invention, the present invention also provides a method for adjusting the phase delay of a bias generator in a dual-cavity system. The dual-cavity system includes: a first cavity device, including: a first cavity including a first chuck and a first bias generator connected to the first chuck; a second cavity device, including: a second cavity including a second chuck and a second bias generator connected to the second chuck. The method includes: adjusting the current phase delay of the first bias generator and the second bias generator to transmit a radio frequency signal in the first cavity and the second cavity.

[0064] According to one or more embodiments of the present invention, the present invention also provides a dual-chamber system. Figure 1 As shown, the dual-cavity system includes the above-mentioned adjustment device, or uses the above-mentioned method for adjusting the phase delay of the bias generator in the dual-cavity system.

[0065] According to one or more embodiments of the present invention, the present invention further provides a plasma chamber, which includes the above-mentioned dual-chamber system.

[0066] The present invention employs a method for adjusting the phase delay of the bias generators in the first and second chambers of a dual-chamber system. This method can address the RF crosstalk problem generated during operation and mitigate the mirror-symmetry of uneven plasma variations between the plasma chambers. Furthermore, after overcoming the RF crosstalk, the present solution can expand the downstream CMP (chemical mechanoplaning) process window. Furthermore, the present invention proposes a tunable range for the phase delay region, defining the optimal adjustable region for the phase delay of the bias generators in the dual-chamber system during operation. This improves etch rate uniformity, limiting end-of-line (EOL) yield loss to less than 0.1%, and post-marking yield loss to less than 0.1%.

[0067] According to one or more embodiments of the present invention, the logic in the regulating device of the present invention can be implemented using a control circuit (control logic, a main control system or a control module), which may include one or more processors and may also include a non-transitory computer-readable medium internally. Specifically, the main control system or the control module may include a microcontroller MCU. The processor used to implement the processing of the logic in the system of the present invention may be, for example, but not limited to, one or more single-core or multi-core processors. The (one or more) processors may include any combination of general-purpose processors and special-purpose processors (for example, graphics processors, application processors, etc.). The processor may be coupled thereto and / or may include a memory / storage device, and may be configured to execute instructions stored in the memory / storage device to implement various applications and / or operating systems running on the controller in the present invention.

[0068] The following are further examples of the present invention:

[0069] Example 1. A device for adjusting the phase delay between bias generators in a dual-cavity system, the dual-cavity system comprising: a first cavity device, comprising: a first cavity including a first chuck and a first bias generator connected to the first chuck; a second cavity device, comprising: a second cavity including a second chuck and a second bias generator connected to the second chuck, wherein the device is configured to: adjust the current phase delay between the first bias generator and the second bias generator to transmit a radio frequency signal in the first cavity and the second cavity.

[0070] Example 2. The device of Example 1, wherein the device is further configured to: cause the first bias generator to send an initial RF signal to the second bias generator through a cable.

[0071] Example 3. The apparatus of Example 1, wherein the apparatus is further configured to adjust the current phase delays of the first bias generator and the second bias generator to be in phase.

[0072] Example 4. The apparatus of example 1, wherein the in-phase is: delaying the phase of the current of the first bias generator and the second bias generator by 45 degrees.

[0073] Example 5. The device according to Example 1, wherein the device is further configured to: when the current phase delays of the first bias generator and the second bias generator are adjusted to be out of phase, the plasma in the dual-cavity system will be respectively non-uniform, and radio frequency crosstalk will be generated.

[0074] Example 6. The apparatus of Example 1, wherein the adjustment region of the phase delay is:

[0075] Safety area: 315 degrees to 90 degrees;

[0076] Tuning area: 90 degrees to 180 degrees and 225 degrees to 315 degrees;

[0077] The poor area is: 180 degrees to 225 degrees;

[0078] The device is further configured to adjust the current phase delay of the first bias generator and the second bias generator to a safe area or a tuning area.

[0079] Example 7. The apparatus of Example 1, wherein the apparatus further comprises an external tuning knob, and wherein the current phase delay between the first bias generator and the second bias generator is adjusted by adjusting the rotation angle of the tuning knob; or wherein the external tuning knob may be located in a dual-chamber system, in a plasma chamber, or in a workstation.

[0080] Example 8. The apparatus of Example 1, wherein a current phase delay between the first bias generator and the second bias generator is related to a difference in left and right etch rates of the wafer.

[0081] Example 9. The device according to Example 8, wherein: when the phase delay is 180 degrees, the absolute value of the difference is the largest, indicating that the plasma between the first cavity and the second cavity is unstable and RF crosstalk occurs; when the phase delay is 45 degrees, the absolute value of the difference is the smallest, indicating that the plasma between the first cavity and the second cavity is stable and no RF crosstalk occurs.

[0082] Example 10. The apparatus of Example 11, wherein a current phase delay between the first bias generator and the second bias generator is related to a DC bias voltage within a plasma chamber in which the dual-chamber system is located.

[0083] Example 11. According to the device described in Example 10, when the phase delay is 180 degrees, the DC bias voltage in the plasma chamber is low, indicating that the plasma between the first cavity and the second cavity is unstable and RF crosstalk occurs; when the phase delay is 45 degrees, the DC bias voltage in the plasma chamber is high, indicating that the plasma between the first cavity and the second cavity is completely dissociated and no RF crosstalk occurs.

[0084] Example 12. The device according to Example 1, wherein the current phase delay between the first bias generator and the second bias generator can be adjusted by a tuning knob, and the adjustment result can be displayed in a visual manner.

[0085] Example 13. A method for adjusting the phase delay of a bias generator in a dual-cavity system, the dual-cavity system comprising: a first cavity device comprising: a first cavity comprising a first chuck and a first bias generator connected to the first chuck; a second cavity device comprising: a second cavity comprising a second chuck and a second bias generator connected to the second chuck, the method comprising: adjusting the current phase delay of the first bias generator and the second bias generator to transmit a radio frequency signal in the first cavity and the second cavity.

[0086] Example 14. The method of Example 13, wherein the current phase delays of the first bias generator and the second bias generator are adjusted to be in phase.

[0087] Example 15. The method of Example 14, wherein the same phase is: delaying the current phase of the first bias generator and the second bias generator by 45 degrees.

[0088] Example 16. The method of Example 15, wherein when the current phase delays of the first bias generator and the second bias generator are adjusted to be out of phase, the plasma in the dual-cavity system will be respectively non-uniform, resulting in radio frequency crosstalk.

[0089] Example 17. The method according to Example 13, wherein the adjustment range of the phase delay is:

[0090] Safety area: 315 degrees to 90 degrees;

[0091] Tuning area: 90 degrees to 180 degrees and 225 degrees to 315 degrees;

[0092] The poor area is 180 degrees to 225 degrees;

[0093] The method includes: adjusting the current phase delay of the first bias generator and the second bias generator to a safe area or a tuning area.

[0094] Example 18. The method according to Example 13, wherein the current phase delay between the first bias generator and the second bias generator is adjusted by adjusting the rotation angle of the tuning knob, and the adjustment result can be displayed in a visual manner.

[0095] Example 19. The method of Example 13, wherein a current phase delay between the first bias generator and the second bias generator is related to a difference in etching rates between left and right sides of the wafer.

[0096] Example 20. The method according to Example 19, wherein: when the phase delay is 180 degrees, the absolute value of the difference is the largest, indicating that the plasma between the first cavity and the second cavity is unstable and RF crosstalk occurs; when the phase delay is 45 degrees, the absolute value of the difference is the smallest, indicating that the plasma between the first cavity and the second cavity is stable and no RF crosstalk occurs.

[0097] Example 21. The method of Example 13, wherein a current phase delay between the first bias generator and the second bias generator is related to a DC bias voltage within a plasma chamber in which the dual-chamber system is located.

[0098] Example 22. A method according to Example 21, wherein: when the phase delay is 180 degrees, the DC bias voltage in the plasma chamber is low, indicating that the plasma between the first cavity and the second cavity is unstable and RF crosstalk occurs; when the phase delay is 45 degrees, the DC bias voltage in the plasma chamber is high, indicating that the plasma between the first cavity and the second cavity is completely dissociated and no RF crosstalk occurs.

[0099] Example 23. A dual-cavity system, comprising the dual-cavity system according to any one of Examples 1-12, or using the method for adjusting phase delay in a dual-cavity system according to any one of Examples 13-22.

[0100] Example 24. A plasma chamber comprising the dual chamber system of Example 23.

[0101] The accompanying drawings and detailed description of the present invention referred to above as examples of the present invention are used to explain the present invention, but do not limit the meaning or scope of the present invention described in the claims. Therefore, those skilled in the art can easily realize modifications from the above description. In addition, those skilled in the art can delete some of the components described herein without degrading performance, or can add other components to improve performance. In addition, those skilled in the art can change the order of the steps of the method described herein according to the environment of the process or equipment. Therefore, the scope of the present invention should not be determined by the embodiments described above, but by the claims and their equivalents.

[0102] While the invention has been described in connection with what are presently considered to be capable embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but on the contrary is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A device for adjusting the phase delay between bias generators in a dual-cavity system, The dual-chamber system comprises: A first cavity device comprising: a first cavity including a first chuck and a first bias generator connected to the first chuck; The second cavity device comprises: a second cavity including a second chuck and a second bias generator connected to the second chuck, The first chuck and the second chuck are used to clamp the wafer, and the first bias generator is connected to the second bias generator via a cable. The device is configured to adjust the current phase delay between the first bias generator and the second bias generator to transmit radio frequency signals in the first cavity and the second cavity.

2. The device according to claim 1, wherein The device is further configured to enable the first bias generator to send an initial radio frequency signal to the second bias generator through a cable.

3. The device according to claim 1, wherein The device is further configured to adjust the current phase delays of the first bias generator and the second bias generator to be in phase. 4 . The apparatus according to claim 3 , wherein the in-phase operation is: delaying the current phases of the first bias generator and the second bias generator by 45 degrees.

5. The apparatus according to claim 1, wherein The adjustment range of the phase delay is: Safety area: 315 degrees to 90 degrees; Tuning area: 90 degrees to 180 degrees and 225 degrees to 315 degrees; The poor area is: 180 degrees to 225 degrees; The device is further configured to adjust the current phase delay of the first bias generator and the second bias generator to a safe area or a tuning area.

6. The apparatus according to claim 1, wherein The device includes an external tuning knob, and the current phase delay between the first bias generator and the second bias generator is adjusted by adjusting the rotation angle of the tuning knob.

7. The apparatus according to claim 1, wherein The current phase delay between the first bias generator and the second bias generator is related to the difference in etching rates between the left and right sides of the wafer.

8. The apparatus according to claim 7, wherein When the phase delay is 180 degrees, the absolute value of the difference is the largest, indicating that the plasma between the first cavity and the second cavity is unstable and radio frequency crosstalk occurs; When the phase delay is 45 degrees, the absolute value of the difference is the smallest, indicating that the plasma between the first cavity and the second cavity is stable and no radio frequency crosstalk occurs.

9. The apparatus according to claim 1, wherein The current phase delay between the first bias generator and the second bias generator is related to the DC bias voltage in the plasma chamber where the dual-chamber system is located.

10. The apparatus according to claim 9, wherein When the phase delay is 180 degrees, the DC bias voltage in the plasma chamber is low, indicating that the plasma between the first cavity and the second cavity is unstable and radio frequency crosstalk occurs; When the phase delay is 45 degrees, the DC bias voltage in the plasma chamber is high, indicating that the plasma between the first cavity and the second cavity is completely dissociated and no radio frequency crosstalk occurs.

11. A method for adjusting the phase delay of a bias generator in a dual-cavity system, The dual-chamber system comprises: A first cavity device comprising: a first cavity including a first chuck and a first bias generator connected to the first chuck; The second cavity device comprises: a second cavity including a second chuck and a second bias generator connected to the second chuck, The first chuck and the second chuck are used to clamp the wafer, and the first bias generator is connected to the second bias generator via a cable. The method comprises: The current phase delay of the first bias generator and the second bias generator is adjusted to transmit radio frequency signals in the first cavity and the second cavity.

12. The method according to claim 11, wherein The first bias generator sends an initial radio frequency signal to the second bias generator through a cable.

13. The method according to claim 11, wherein The current phase delays of the first bias generator and the second bias generator are adjusted to be in phase.

14. The method according to claim 13, wherein the same phase is: delaying the current phases of the first bias generator and the second bias generator by 45 degrees.

15. The method according to claim 11, wherein The adjustment range of the phase delay is: Safety area: 315 degrees to 90 degrees; Tuning area: 90 degrees to 180 degrees and 225 degrees to 315 degrees; The poor area is 180 degrees to 225 degrees; The method comprises: The current phase delay between the first bias generator and the second bias generator is adjusted to a safe region or a tuning region.

16. The method according to claim 11, wherein The current phase delay between the first bias generator and the second bias generator is adjusted by adjusting the rotation angle of the tuning knob.

17. The method according to claim 11, wherein The current phase delay between the first bias generator and the second bias generator is related to the difference in etching rates between the left and right sides of the wafer.

18. The method according to claim 17, wherein: When the phase delay is 180 degrees, the absolute value of the difference is the largest, indicating that the plasma between the first cavity and the second cavity is unstable and radio frequency crosstalk occurs; When the phase delay is 45 degrees, the absolute value of the difference is the smallest, indicating that the plasma between the first cavity and the second cavity is stable and no radio frequency crosstalk occurs.

19. The method according to claim 11, wherein The current phase delay between the first bias generator and the second bias generator is related to the DC bias voltage in the plasma chamber where the dual-chamber system is located.

20. The method of claim 19, wherein: When the phase delay is 180 degrees, the DC bias voltage in the plasma chamber is low, indicating that the plasma between the first cavity and the second cavity is unstable and radio frequency crosstalk occurs; When the phase delay is 45 degrees, the DC bias voltage in the plasma chamber is high, indicating that the plasma between the first cavity and the second cavity is completely dissociated and no radio frequency crosstalk occurs.

21. A dual-cavity system, comprising the device for adjusting the phase delay of a bias generator in a dual-cavity system according to any one of claims 1-10, or using the method for adjusting the phase delay of a bias generator in a dual-cavity system according to any one of claims 11-20.

22. A plasma chamber comprising the dual chamber system according to claim 21.

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