Multi-cavity plasma processing device and method for reducing emission spectrum interference between cavities

Abstract

The invention discloses a multi-cavity plasma processing device and a method for reducing emission spectrum interference between cavities. The device comprises a plurality of processing cavities, each processing cavity comprises a base, a gas injection device and a spectrum detection device, the base is arranged in the processing cavity and used for bearing wafers, the gas injection device is used for introducing reaction gas, the spectrum detection device is used for judging process end points in the processing cavities, and the processing cavities are correspondingly communicated with a plurality of second pipelines; the pressure detection device is communicated with the plurality of second pipelines through a first pipeline so as to detect the pressure in the plurality of processing cavities, and each second pipeline is provided with a valve; and the controller is used for receiving the process end point signal of the spectrum detection device and controlling the valve corresponding to the chamber where the spectrum detection device is located to be switched off according to the process end point signal. According to the invention, the air pressure crosstalk among multiple cavities can be improved, and the offset of the emission spectrum intensity is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor equipment, and in particular to a multi-cavity plasma processing device and a method for reducing emission spectrum interference between chambers. Background Art

[0002] Plasma processing is a common technology in the field of integrated circuits. This process step is carried out in the processing chamber of a plasma processing device. During the processing, process gas is introduced into the processing chamber, and then radio frequency power is applied to the process gas introduced into the processing chamber through upper and lower electrodes to generate plasma. The plasma etches the material layer on the surface of the wafer, and then the wafer is processed.

[0003] In order to improve the efficiency of the process, multiple processing chambers can be set on a plasma processing device, and each processing chamber processes wafers in parallel, thereby greatly improving production efficiency. As the precision requirements of the processing technology continue to increase, higher requirements are also placed on the structural design and parameter indicators of multi-cavity plasma processing devices. Summary of the invention

[0004] The object of the present invention is to provide a multi-cavity plasma processing device and a method for reducing emission spectrum interference between chambers, which can improve the gas pressure crosstalk between multiple cavities and reduce the deviation of emission spectrum intensity.

[0005] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0006] A multi-cavity plasma processing device, comprising:

[0007] A plurality of processing chambers, each of the processing chambers comprising a base arranged in the chamber for carrying a wafer, a gas injection device for introducing a reaction gas, and a spectrum detection device for determining a process endpoint in the processing chamber, and the plurality of processing chambers are correspondingly connected to a plurality of second pipelines;

[0008] a pressure detection device, which is connected to the plurality of second pipelines through the first pipeline to detect the pressure in the plurality of processing chambers, and each second pipeline is provided with a valve;

[0009] The controller is used to receive a process endpoint signal of the spectrum detection device, and control the valve corresponding to the chamber where the spectrum detection device is located to disconnect according to the process endpoint signal.

[0010] Preferably, it also includes a Tesla valve, which is arranged in the first pipeline.

[0011] Preferably, it further comprises a plurality of Tesla valves, wherein the plurality of Tesla valves are respectively arranged in the plurality of the second pipelines.

[0012] Preferably, the low damping flow directions of the plurality of Tesla valves are the same.

[0013] Preferably, each Tesla valve is located between the valve and the first pipeline.

[0014] Preferably, it also includes a Tesla valve arranged in the first pipeline, and its low damping flow direction is the same as that of the Tesla valves in each of the second pipelines.

[0015] Preferably, the low damping flow direction of the Tesla valve is from the pressure detection device to the processing chamber.

[0016] Preferably, it also includes an exhaust unit communicated with each of the processing chambers and electrically connected to the controller, for exhausting process waste gas in each of the processing chambers out of the chamber and maintaining the gas pressure in each of the processing chambers stable.

[0017] A method for reducing emission spectrum interference between chambers, applied to any of the above-mentioned multi-cavity plasma processing devices, comprises the steps of:

[0018] Placing a plurality of wafers on bases of a plurality of processing chambers respectively and performing process treatments;

[0019] The pressure detection device detects the air pressure in each of the processing chambers through the first pipeline and the second pipeline;

[0020] When the etching endpoint detection device of any of the processing chambers detects the process endpoint, the valve corresponding to the processing chamber is closed.

[0021] Preferably, it also includes:

[0022] When the etching endpoint detection device of any of the processing chambers detects a process endpoint, extinguishing the plasma of the processing chamber;

[0023] Wherein, extinguishing the plasma and closing the valve are performed simultaneously.

[0024] Preferably, the multi-chamber plasma processing device includes an exhaust unit, and the controller adjusts the exhaust power of the exhaust unit according to the pressure detection value of the pressure detection device, and further includes:

[0025] When the plasma in any processing chamber is extinguished, if the pressure in the processing chamber increases, the actual pumping power of the exhaust unit is less than the pumping power adjusted according to the pressure detection value; if the pressure in the processing chamber decreases, the actual pumping power of the exhaust unit is greater than the pumping power adjusted according to the pressure detection value.

[0026] Preferably, the actual pumping power is halved compared to the pumping power adjusted according to the pressure detection value; or, the actual pumping power is doubled compared to the pumping power adjusted according to the pressure detection value.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] 1. By setting a switch valve on each second pipeline and controlling its closing in association with the process endpoint signal, it is possible to reduce the pressure fluctuation caused by extinguishing the plasma from interfering with other processing chambers and pressure detection devices;

[0029] 2. By installing a Tesla valve on the first pipeline, the remaining air pressure fluctuation can be further reduced;

[0030] 3. By setting a Tesla valve with the same damping flow direction on each second pipeline, it can achieve a faster and better effect of smoothing air pressure fluctuations;

[0031] 4. By setting the high damping flow direction of the Tesla valve toward the pressure detection device, the pressure detection device can maintain the pressure detection value stable to the maximum extent;

[0032] 5. By arranging the Tesla valves on each second pipeline between the switch valve and the first pipeline, and with the high damping flow direction facing the pressure detection device, a more prominent effect of smoothing air pressure fluctuations can be achieved;

[0033] 6. By arranging Tesla valves with the same damping flow direction on the first pipeline and each second pipeline, a two-stage filter can be formed, which has the best effect of smoothing air pressure fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for describing the embodiments are briefly introduced below. 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.

[0035] Figure 1 It is an emission spectrum intensity curve diagram of a dual-cavity plasma processing device in the prior art;

[0036] Figure 2 A relationship diagram of a pressure detection value curve, an emission spectrum intensity curve, and an exhaust unit valve opening curve of a dual-chamber plasma processing device in the prior art;

[0037] Figure 3 is a schematic diagram of one embodiment of a multi-cavity plasma processing device of the present invention;

[0038] Figure 4 is an emission spectrum intensity curve diagram of one embodiment of the present invention;

[0039] Figure 5A sequential comparison diagram of emission spectrum intensity curves of one embodiment of the present invention;

[0040] Figure 6 A relationship diagram of a pressure detection value curve, an emission spectrum intensity curve, and an exhaust unit valve opening curve of a dual-chamber plasma processing device according to one embodiment of the present invention;

[0041] Figure 7 is a schematic diagram of one embodiment of a multi-cavity plasma processing device of the present invention;

[0042] Figure 8a Schematic diagram of low damping flow direction of Tesla valve;

[0043] Figure 8b Schematic diagram of the high damping flow direction of the Tesla valve;

[0044] Fig. 9 A comparison diagram of the pressure detection value curves of the Tesla valve of the present invention;

[0045] Fig.10 is a schematic diagram of one embodiment of a multi-cavity plasma processing device of the present invention;

[0046] Fig.11 is a schematic diagram of one embodiment of a multi-cavity plasma processing device of the present invention;

[0047] Fig.12 FIG. 1 is a schematic diagram of one embodiment of a multi-cavity plasma processing device of the present invention. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described below in conjunction with the accompanying drawings. The described embodiments should not be regarded as limiting the present invention. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0049] In the following description, reference is made to “some embodiments”, “one or more embodiments”, which describe a subset of all possible embodiments, but it can be understood that “some embodiments”, “one or more embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0050] In the following description, the terms "first\second\third" are only used to distinguish similar objects and do not represent a specific ordering of the objects. It can be understood that "first\second\third" can be interchanged with a specific order or sequence where permitted, so that the embodiments of the present invention described here can be implemented in an order other than that shown or described.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein are only for the purpose of describing the embodiments of the present invention and are not intended to limit the present invention.

[0052] In order to ensure the synchronous operation of the processing processes in different processing chambers, the multi-chamber plasma processing device needs to set the exhaust areas of multiple processing chambers to be fluid-connected and fluid-connected with a common exhaust unit, through which the by-products generated by the reaction process in each processing chamber are discharged out of the chamber. At the same time, the exhaust unit is also used to maintain the stability of the air pressure in each processing chamber. Usually, the air pressure of each processing chamber is detected by a pressure detection device shared by each processing chamber, and the pressure detection value is fed back to the controller electrically connected thereto. The controller adjusts the exhaust power of the exhaust unit in real time according to the received pressure detection value to keep the air pressure in each processing chamber as stable as possible. Among them, the present invention does not specifically limit the implementation method of adjusting the exhaust power of the exhaust unit. In some embodiments, the exhaust power of the exhaust unit is adjusted by adjusting the opening of the exhaust valve connecting the exhaust unit and the processing chamber. The speed of the exhaust unit fan remains unchanged. The larger the opening of the exhaust valve, the greater the exhaust power, and the smaller the opening, the smaller the exhaust power.

[0053] Since the process of each processing chamber often cannot reach the process endpoint at the same time, it is necessary to monitor the process endpoint of each chamber separately through the spectrum detection device of each processing chamber. During the process, each spectrum detection device continuously monitors the emission spectrum intensity in its corresponding processing chamber. When it detects that the emission spectrum intensity in a processing chamber has changed by a certain amplitude, it is judged that the processing chamber has reached the process endpoint. The spectrum detection device sends a process endpoint signal to the controller electrically connected to it; after receiving the process endpoint signal, the controller extinguishes the plasma in the processing chamber and stops the process of the processing chamber.

[0054] However, when the plasma in one of the processing chambers is extinguished, it will interfere with the emission spectrum intensity of other connected processing chambers, causing them to change significantly, thereby affecting the accuracy of the process endpoint monitoring and affecting the process processing of the chamber. Figure 1The emission spectrum intensity curve of a dual-chamber plasma processing device of the prior art is shown, in which the horizontal axis is time (unit: seconds) and the vertical axis is the relative spectrum intensity relative to a certain reference value. The dual-chamber plasma processing device includes processing chambers A1 and A2 that are connected to each other, and the two curves correspond to the relative spectrum intensity of a certain wavelength of processing chambers A1 and A2 respectively. It can be seen from the figure that processing chamber A2 reaches the process end point at time t, extinguishes the plasma in its chamber, and its relative spectrum intensity curve ends; and when processing chamber A2 extinguishes the plasma, the relative spectrum intensity of processing chamber A1 rises sharply from the original 7249 to 7569, with a change range of +4.4%, indicating that after processing chamber A2 extinguishes the plasma, it causes a large interference to the emission spectrum intensity of processing chamber A1.

[0055] Further, the reason for the interference with the intensity of the emission spectrum of the processing chamber A1 is the change in the air pressure in the chamber. When the plasma in the processing chamber A2 is extinguished, it will cause a change in air pressure, resulting in an airflow impact on the pressure detection device, making the pressure detection value of the pressure detection device inaccurate. Since the controller adjusts the exhaust power of the exhaust unit according to the pressure detection value, the inaccurate pressure detection value will cause the incorrect adjustment of the exhaust power of the exhaust unit, which will lead to changes in the air pressure in the processing chamber A1. Moreover, due to the connection and closed design between the chambers, this airflow impact not only includes a transient impact, but also includes a reciprocating oscillation impact between the interconnected chambers and the pressure detection device, causing the pressure detection value of the pressure detection device to be continuously inaccurate, aggravating and prolonging the air pressure change in the processing chamber A1, and causing continuous interference with the emission spectrum intensity of the processing chamber A1. Due to the interconnected design between the chambers of the multi-chamber plasma processing device, this mutual interference cannot be completely eliminated and can only be reduced as much as possible through measures.

[0056] Attached Figure 2 Shown is the attached Figure 1The relationship diagram of the pressure detection value curve (Y1) of the dual-chamber plasma processing device, the emission spectrum intensity curve (Y2) of a certain wavelength in the processing chamber A1, and the exhaust valve opening curve (Y3) of the exhaust unit, the horizontal axis of the figure is time (unit: second), the vertical axis of Y1 is the gas pressure (unit: millitorr), the vertical axis of Y2 is the relative spectrum intensity relative to a certain reference value, and the vertical axis of Y3 is the relative opening relative to a certain reference value. The time t corresponds to the extinguishing of the plasma in the processing chamber A2. It can be seen from the figure that before the time t, both processing chambers have not reached the process endpoint, and the curves Y1, Y2, and Y3 remain basically stable. Starting from time t, curve Y1 shows an obvious spike waveform, indicating that the pressure detection device is impacted by the airflow caused by the extinguishing plasma in processing chamber A2; and curve Y3 also produces a corresponding spike waveform, that is, the controller adjusts the exhaust power of the exhaust unit in real time according to the feedback of the pressure detection device; and curve Y2 is affected by the air pressure. Starting from the peak waveform of curve Y1, the relative spectral intensity shifts from about 6800 to about 7000 and continues to maintain this offset, indicating that the offset of curve Y1 cannot be corrected by adjusting the exhaust power of the exhaust unit alone, and the offset will be maintained for a long time.

[0057] Based on the above technical problems, the present invention provides a multi-cavity plasma processing device and a method for reducing emission spectrum interference between chambers. To simplify the description, this embodiment takes a dual-cavity plasma processing device as an example. However, it can be understood that it can be expanded and applied to a multi-cavity structure with more than two cavities based on the same principle. Figures 3 to 12 Provide detailed explanation.

[0058] Attached Figure 3 A first embodiment of a multi-cavity plasma processing device of the present invention is shown, which comprises:

[0059] The processing chamber A and the processing chamber B are respectively surrounded by the outer walls of their respective processing chambers. Each processing chamber is provided with a base 10 for carrying wafers, and a gas injection device 13 located above the base 10. The gas injection device 13 is connected to a gas supply device 14 outside the chamber, and is used to introduce the reaction gas of the gas supply device 14 into the chamber. The processing area is between the gas injection device 13 and the base 10. Usually, the gas injection device 13 serves as an upper electrode, and the base 10 serves as a lower electrode. At least one RF power supply 12 applies RF energy to at least one of the upper electrode and the lower electrode through an impedance matching network 11, and generates a RF electric field between the upper electrode and the lower electrode, ignites the reaction gas in the processing area and dissociates it into plasma. The plasma reaching the upper surface of the wafer can perform etching and other treatments on the wafer. Each processing chamber also includes a spectral detection device 8 arranged in the chamber for monitoring the process endpoint of each processing chamber. During the process, each spectral detection device 8 continuously monitors the emission spectrum intensity in its processing chamber. When a wafer in a processing chamber completes a certain process step and reaches the process endpoint, the emission spectrum intensity in the chamber will undergo a significant change. After the spectral detection device 8 detects it, the controller determines that the processing chamber has reached the process endpoint and sends a process endpoint signal.

[0060] The pressure detection device 2 shared by the processing chamber A and the processing chamber B is arranged outside the two chambers, and is connected to the fluids of the two chambers through the pressure detection pipeline, and is used to detect the air pressure in the two chambers and output the pressure detection value. The pressure detection pipeline includes a first pipeline 3 connected to the pressure detection device 2, and two second pipelines 4 connected to the first pipeline 3 and arranged in parallel, and the two second pipelines 4 are respectively connected to the processing chamber A and the processing chamber B.

[0061] The exhaust unit 7 shared by the processing chamber A and the processing chamber B is arranged below the two chambers and is fluidically connected to the exhaust areas of the two chambers (located below the base 10) for exhausting the reaction byproducts in the two chambers and controlling and maintaining the pressure in the two chambers stable.

[0062] The controller 9 is arranged outside the two chambers and is electrically connected to the spectrum detection devices 8, pressure detection devices 2 and exhaust units 7 of the two chambers respectively. It is used to receive the process endpoint signal of each spectrum detection device 8, and extinguish the plasma in the processing chamber when receiving the process endpoint signal, so as to control the process processing progress of each processing chamber; and it is used to receive the pressure detection value of the pressure detection device 2, dynamically adjust the exhaust power of the exhaust unit 7 according to the pressure detection value, and maintain the pressure in the two chambers stable.

[0063] A switch valve 5 is provided on each second pipeline 4. Each switch valve 5 is electrically connected to the controller 9, and can be controlled by the controller 9 to open or close the valve body, so that the fluid passage of the second pipeline 4 where it is located is opened or closed. The controller 9 associates the closing of each switch valve 5 with the process endpoint signal emitted by the spectrum detection device 8 in the same cavity. When the controller 9 receives the process endpoint signal of the spectrum detection device 8 of a certain processing cavity, the controller 9 controls the switch valve 5 corresponding to the processing cavity to close, thereby blocking the fluid passage of the second pipeline 4 connected to the processing cavity, and reducing the pressure fluctuation caused by the extinguishing of the plasma in the processing cavity to disturb the pressure detection device 2.

[0064] Attached Figure 4 The emission spectrum intensity curve of a certain wavelength in the processing chamber B of the first embodiment is shown. The horizontal axis in the figure is time (unit: second), and the vertical axis is the relative spectrum intensity relative to a certain reference value. The horizontal axis is divided into stages I, II, III, IV, and V in sequence. Among them, stage I is that both the processing chamber A and the processing chamber B have not reached the process endpoint. At this time, the relative spectrum intensity of the processing chamber B is stable at 7250. Stage II is that the processing chamber A reaches the process endpoint and extinguishes the plasma. In this stage, the relative spectrum intensity of the processing chamber B is disturbed and rises sharply to about 7550. Stage III is that the switch valve 5 does not act, and only the controller 9 adjusts the exhaust power of the exhaust unit 7 according to the feedback of the pressure detection device. In this stage, the relative spectrum intensity of the processing chamber B is maintained at 7550, which is +4.1% compared with the offset amplitude of stage I. It can be seen that only adjusting the exhaust power of the exhaust unit 7 cannot correct the emission spectrum intensity offset of the processing chamber B, and the offset will be maintained for a long time. In stage IV, the switch valve 5 on the second pipeline 4 of the processing chamber A is closed, and the relative spectral intensity of the processing chamber B decreases accordingly, and is maintained at about 7330 in the subsequent stage V. Compared with stage I, the deviation amplitude is only +1.1%. It can be seen that closing the corresponding valve 5 has a better effect of isolating interference.

[0065] Preferably, in some embodiments, the controller 9 controls the extinguishing of the plasma in the processing chamber and the closing of the switch valve 5 corresponding to the processing chamber to be performed synchronously, thereby being able to block the fluid passage of the second pipeline 4 connected to the processing chamber at the first time, and minimizing the time and intensity of the gas pressure crosstalk to the pressure detection device 2 as much as possible. Figure 5The following is a sequential comparison of the emission spectrum intensity curves of a certain wavelength under different conditions for the processing chambers A and B of the multi-chamber plasma processing device of the first embodiment. The horizontal coordinates are all time (unit: seconds), and are divided into stages I, II, and III in sequence, and the vertical coordinates are all relative spectrum intensities relative to a certain reference value. Among them, stage I is when both the processing chamber A and the processing chamber B have not reached the process endpoint; stage II is when the processing chamber A reaches the process endpoint and the plasma is extinguished; stage III is the subsequent state of stage II. In the figure, the second column from the left shows the sequential change curves of the emission spectrum intensity of a certain wavelength of the processing chambers A and B when the switch valve 5 is not closed throughout the whole process. It can be seen that the emission spectrum intensity offset amplitude of the processing chamber B in this case is +4.3%. The fourth column from the left shows the sequential change curves of the emission spectrum intensity of a certain wavelength of the processing chambers A and B when the processing chamber A reaches the process endpoint, the plasma in it is extinguished, and the switch valve 5 corresponding to the chamber is closed at the same time. It can be seen that in this case, the deviation of the emission spectrum intensity of the processing chamber B in stage II and stage III is significantly smaller than that in the case where the switch valve 5 is not closed, and the deviation amplitude is only +0.8%, which has a good interference isolation effect.

[0066] Attached Figure 6 The relationship diagram of the pressure detection value change curve (Y1) output by the pressure detection device 2 of the multi-cavity plasma processing device of the first embodiment, the emission spectrum intensity change curve (Y2) of a certain wavelength in the processing chamber B, and the exhaust valve opening curve (Y3) of the exhaust unit 7 is shown. The horizontal axis in the figure is time (unit: second), the vertical axis of the curve Y1 is the gas pressure (unit: millitorr), the vertical axis of the curve Y2 is the relative spectrum intensity relative to a certain reference value, and the vertical axis of the curve Y3 is the relative opening relative to a certain reference value. The t1 stage corresponds to the plasma in the processing chamber A extinguishing the chamber and closing the corresponding switch valve 5 at the same time. It can be seen that the curve Y2 has a small jitter in the t1 and t2 stages, during which the relative spectrum intensity jitters slightly from 7530 and rises to 7593, with an increase of 0.84%; then it drops and stabilizes at 7533, with a decrease of 0.78%. It can be seen that by closing the corresponding switch valve 5 when extinguishing the plasma, the emission spectrum intensity interference between chambers can be greatly reduced. However, in more demanding processes, such as gate etch, this disturbance still cannot meet the process requirements, and the jitter of the curve Y2 at stages t1 and t2 needs to be further smoothed.

[0067] Further analysis of the reasons for the jitter of curve Y2 at stages t1 and t2 shows that although the first embodiment described above blocks the pressure detection pipeline between processing chamber A and processing chamber B and pressure detection device 2 by closing the switch valve 5 corresponding to processing chamber A, the gas pressure shock caused by the extinguishing of plasma in processing chamber A is prevented from flowing into pressure detection device 2 through the pressure detection pipeline. However, on the one hand, the gas pressure shock will still enter the pressure detection device 2 through the exhaust area of ​​the interconnected processing chambers A and B. Although the exhaust unit 7 will release most of the gas pressure shock, it will still cause a small jitter of curve Y2; on the other hand, a certain gas pressure shock will also be generated when the switch valve 5 is closed, and enter the pressure detection device 2 through the pressure detection pipeline. The above two aspects of gas pressure shock will also oscillate back and forth between the cavity and the pressure detection device 2, causing the jitter of curve Y2.

[0068] Therefore, preferably, the present invention provides a second embodiment:

[0069] As attached Figure 7 As shown in FIG. 1 , based on the first embodiment, a Tesla valve 6 is provided on the first pipeline 3. The Tesla valve is a passive fluid control valve, and its structure is composed of straight channels and curved channels, so that it has the following characteristics: Figure 8a The low damping flow direction shown and the Figure 8b As shown in the high damping flow direction, when the fluid flows along the low damping flow direction, the resistance is very small and the flow rate is large, while when it flows along the high damping flow direction, it will produce obvious resistance and the flow rate is very small, so that the bidirectional flow rate and flow rate have obvious differences. Therefore, by setting the Tesla valve 6 on the first pipeline 3, its high damping flow direction can be used to alleviate the impact of sudden changes in air pressure on the pressure detection device 2, so that the air pressure curve Y1 becomes gentle and the reciprocating shock is reduced; and through its low damping flow direction, it can perform normal intracavity air pressure detection. Specifically, the attached Figure 7 In the figure, the switch valve 5a is arranged on the second pipeline 4a connected to the processing chamber A, and the switch valve 5b is arranged on the second pipeline 4b connected to the processing chamber B; when the processing chamber A extinguishes the plasma and closes its corresponding switch valve 5a, when the airflow passes through the first pipeline 3, the high damping flow direction of the Tesla valve 6 will hinder and mitigate the impact force of the airflow, thereby reducing the reciprocating oscillation impact between the cavity and the pressure detection device 2.

[0070] Attached Fig. 9 Shown is the attached Figure 6 The comparison between the pressure curve Y1 in FIG. 1 and the pressure curve Y1' after the Tesla valve 6 is installed shows that a better smoothing effect is achieved by installing the Tesla valve 6. The damping flow direction of the Tesla valve 6 can be set to any direction, because when the airflow moves back and forth on the first pipeline 3, it will flow through the high damping flow direction of the Tesla valve 6, thereby reducing the back and forth shock of the airflow.

[0071] Among them, preferably, the low-damping flow direction of the Tesla valve 6 is the direction from the pressure detection device 2 to the processing chamber, that is, the high-damping flow direction is the direction from the processing chamber to the pressure detection device 2, which can hinder the initial impact of the airflow on the pressure detection device 2, so that the pressure detection device 2 can maintain the pressure detection value stable to the maximum extent, and avoid the exhaust unit 7 from being affected by the initial impact and erroneous operation.

[0072] Furthermore, the present invention also provides a third embodiment:

[0073] On the basis of the first embodiment, the number of Tesla valves that matches the number of the second pipelines 4 is added, and each Tesla valve is arranged on each second pipeline 4 in a one-to-one correspondence, and the damping flow direction of each Tesla valve is consistent, that is, the high (low) damping flow direction of each Tesla valve is toward the pressure detection device 2, or toward the processing chamber. Fig.10 As shown, in some embodiments, the Tesla valve 6a is arranged on the second pipeline 4a connected to the processing chamber A, which is located between the switch valve 5a and the processing chamber; the Tesla valve 6b is arranged on the second pipeline 4b connected to the processing chamber B, which is located between the switch valve 5a and the processing chamber; and the damping flow directions of the Tesla valves 6a and 6b are consistent. When the processing chamber A extinguishes the plasma and closes its corresponding switch valve 5a, when the airflow passes through each second pipeline, the high damping flow direction of each Tesla valve is hindered to mitigate its impact force, thereby reducing the reciprocating shock impact on the pressure detection device 2. Compared with the second embodiment, due to the larger number of Tesla valves, it can have a faster and better airflow reduction effect. Further, more preferably, the high damping flow direction of the Tesla valves 6a and 6b is from the processing chamber to the pressure detection device 2, and the high damping flow direction of the Tesla valve 6b can be used to hinder the first impact of the airflow through the processing chamber B-pressure detection pipeline on the pressure detection device 2, so that the pressure detection device 2 reduces the jitter of the pressure detection value, and reduces the erroneous action of the exhaust unit 7 affected by the initial impact.

[0074] Preferably, as attached Fig.11 As shown in FIG. 1 , in some embodiments, the Tesla valve 6a is disposed between the switch valve 5a and the first pipeline 3; the Tesla valve 6b is disposed between the switch valve 5b and the first pipeline 3. Since the Tesla valve 6a is located between the switch valve 5a and the pressure detection device 2, this embodiment is different from the attached Fig.10In the embodiment, after the switch valve 5a is closed, the pressure detection pipeline between the switch valve 5a and the pressure detection device 2 has a Tesla valve 6a that can reduce the air pressure shock, so that the shock air pressure of this section of the pipeline can be reduced faster and more directly, and the pressure detection device 2 is subjected to the shock for a shorter time. Further, more preferably, in some embodiments, the high-damping flow direction of the Tesla valves 6a and 6b is from the processing chamber to the pressure detection device 2, which can hinder the first impact of the two airflows through the second pipeline 4a-first pipeline 3 and through the second pipeline 4b-first pipeline 3 on the pressure detection device 2, so that the pressure detection device 2 can maintain the stability of the pressure detection value to the maximum extent, and avoid the exhaust unit 7 from being affected by the initial impact and erroneous operation.

[0075] Furthermore, the present invention also provides a fourth embodiment:

[0076] As attached Fig.12 As shown, the second embodiment is combined with the third embodiment, that is, a Tesla valve 6 is provided in the first pipeline, a Tesla valve 6a is provided in the second pipeline 4a, and a Tesla valve 6b is provided in the second pipeline 4b, and the damping flow direction of each Tesla valve is consistent, so that the pressure detection device 2 can perform air pressure detection through the high (low) damping flow direction of each Tesla valve. Compared with the third embodiment, this embodiment has a two-stage filtering structure between the pressure detection device 2 and each processing chamber, which has a more prominent airflow reduction effect and can further smooth the jitter of the air pressure curve Y1.

[0077] Preferably, in some embodiments, the Tesla valve 6a is located between the switch valve 5a and the first pipeline 3, and the Tesla valve 6b is located between the switch valve 5b and the first pipeline 3. Since the Tesla valve 6a is located between the switch valve 5a and the pressure detection device 2, after the switch valve 5a is closed, the pressure detection pipeline between the switch valve 5a and the pressure detection device 2 has a two-stage filtering structure of the Tesla valve 6a and the Tesla valve 6. Compared with the embodiment in which the Tesla valves 6a and 6b are arranged between the switch valve 5a and the processing chamber, this embodiment can reduce the impact gas pressure of the pipeline more quickly and directly, and the pressure detection device 2 is impacted for a shorter time.

[0078] More preferably, the high-damping flow direction of each Tesla valve is from the processing chamber to the pressure detection device 2, which can hinder the initial impact of the two airflows through the second pipeline 4a and the first pipeline 3 and through the second pipeline 4b and the first pipeline 3 on the pressure detection device 2, so that the pressure detection device 2 can maintain the stability of the pressure detection value to the maximum extent, and avoid the exhaust unit 7 from being affected by the initial impact and erroneous operation.

[0079] In addition, the present invention further provides a method for reducing emission spectrum interference between chambers, which is applied to a multi-cavity plasma processing device of any one of the above embodiments, comprising the steps of:

[0080] A plurality of wafers are placed on the bases 10 of a plurality of processing chambers respectively and are processed.

[0081] The pressure detection device 2 detects the gas pressure in each processing chamber through the first pipeline 3 and the second pipeline 4.

[0082] When the etching endpoint detection device of any processing chamber detects the process endpoint, the switch valve 5 corresponding to the processing chamber is closed, and the plasma of the processing chamber is extinguished; preferably, the plasma is extinguished and the switch valve 5 is closed at the same time, so that the fluid passage of the second pipeline 4 connected to the processing chamber can be blocked at the first time, thereby minimizing the time and intensity of the gas pressure crosstalk to the pressure detection device 2 as much as possible.

[0083] The controller 9 adjusts the exhaust valve opening of the exhaust unit 7 according to the pressure detection value of the pressure detection device 2 to control its exhaust power. When the plasma in any processing chamber is extinguished, the pressure of the chamber will change, and the change of the chamber pressure may increase or decrease according to the specific process: for example, in the reaction of etching Al (the reaction chemical formula is 2Al+3Cl2 · →2AlCl3), the volume of the reaction gas in the chamber is significantly reduced, and the pressure in the chamber is reduced; i O2 reaction (the reaction formula is S i O2+CF4→S i F4+CO2), the volume of the reaction gas in the chamber increases significantly, and the pressure in the chamber increases. Preferably, when the plasma is extinguished in any processing chamber, if the pressure in the processing chamber increases, the actual exhaust valve opening of the exhaust unit 7 is smaller than the exhaust valve opening adjusted according to the pressure detection value, because the pressure detection value of the pressure detection device 2 is higher than the actual pressure value in the chamber at this time, so the actual exhaust valve opening should be made smaller to correct the pressure measurement deviation; further, in this case, preferably, the actual exhaust valve opening is halved compared to the exhaust valve opening adjusted according to the pressure detection value, that is, if the exhaust valve opening should be 2% according to the pressure detection value, then the actual exhaust valve opening is 1%. Alternatively, after the plasma is extinguished in any processing chamber, if the pressure in the processing chamber decreases, the actual exhaust valve opening of the exhaust unit 7 is greater than the exhaust valve opening adjusted according to the pressure detection value. Because the pressure detection value of the pressure detection device 2 will be lower than the actual pressure value in the chamber at this time, the actual exhaust valve opening should be made larger to correct the pressure measurement deviation; further, in this case, preferably, the actual exhaust valve opening is doubled compared to the exhaust valve opening adjusted according to the pressure detection value, that is, if the exhaust valve opening should be 1% according to the pressure detection value, then the actual exhaust valve opening is 2%.

[0084] When a Tesla valve is provided on the first pipeline 3 , the airflow is reduced by the high damping flow direction of the Tesla valve when passing through the first pipeline 3 .

[0085] When a Tesla valve is provided on each second pipeline 4 , the airflow is reduced by the high-damping flow direction of the Tesla valve when passing through the second pipeline 4 .

[0086] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement and improvement made within the spirit and scope of the present invention are included in the protection scope of the present invention.

Claims

1. A multi-chamber plasma processing device, characterized in that: It includes: A plurality of processing chambers, each of the processing chambers comprising a base arranged in the chamber for carrying a wafer, a gas injection device for introducing a reaction gas, and a spectrum detection device for determining a process endpoint in the processing chamber, and the plurality of processing chambers are correspondingly connected to a plurality of second pipelines; a pressure detection device, which is connected to the plurality of second pipelines through the first pipeline to detect the pressure in the plurality of processing chambers, and each second pipeline is provided with a valve; The controller is used to receive a process endpoint signal of the spectrum detection device, and control the valve corresponding to the chamber where the spectrum detection device is located to disconnect according to the process endpoint signal.

2. The multi-chamber plasma processing device according to claim 1, characterized in that: It also includes a Tesla valve, which is arranged in the first pipeline.

3. The multi-chamber plasma processing device according to claim 1, characterized in that: It also includes a plurality of Tesla valves, which are respectively arranged in a plurality of the second pipelines.

4. The multi-chamber plasma processing device according to claim 3, characterized in that: The low damping flow directions of the multiple Tesla valves are the same.

5. The multi-chamber plasma processing device according to claim 4, characterized in that: Each Tesla valve is located between the valve and the first pipeline.

6. The multi-chamber plasma processing device according to claim 4 or 5, characterized in that: It also includes a Tesla valve arranged in the first pipeline, and its low damping flow direction is the same as that of the Tesla valves in each of the second pipelines.

7. The multi-chamber plasma processing device according to any one of claims 2 to 6, characterized in that: The low damping flow direction of the Tesla valve is from the pressure detection device to the processing chamber.

8. The multi-chamber plasma processing device according to any one of claims 1 to 7, characterized in that: It also includes an exhaust unit that is communicated with each of the processing chambers and electrically connected to the controller, and is used to discharge the process waste gas in each of the processing chambers out of the chamber and maintain the gas pressure in each of the processing chambers stable.

9. A method for reducing emission spectrum interference between chambers, applied to a multi-cavity plasma processing device as claimed in any one of claims 1 to 7, characterized in that: Includes steps: Placing a plurality of wafers on bases of a plurality of processing chambers respectively and performing process treatments; The pressure detection device detects the air pressure in each of the processing chambers through the first pipeline and the second pipeline; When the etching endpoint detection device of any of the processing chambers detects the process endpoint, the valve corresponding to the processing chamber is closed.

10. The method for reducing emission spectrum interference between chambers according to claim 9, characterized in that: Also includes: When the etching endpoint detection device of any of the processing chambers detects a process endpoint, extinguishing the plasma of the processing chamber; Wherein, extinguishing the plasma and closing the valve are performed simultaneously.

11. The method for reducing emission spectrum interference between chambers according to any one of claims 9 to 10, wherein: The multi-chamber plasma processing device includes an exhaust unit, and the controller adjusts the exhaust power of the exhaust unit according to the pressure detection value of the pressure detection device, characterized in that it also includes: When the plasma in any processing chamber is extinguished, if the pressure in the processing chamber increases, the actual pumping power of the exhaust unit is less than the pumping power adjusted according to the pressure detection value; if the pressure in the processing chamber decreases, the actual pumping power of the exhaust unit is greater than the pumping power adjusted according to the pressure detection value.

12. The method for reducing emission spectrum interference between chambers according to claim 11, characterized in that: The actual pumping power is halved compared to the pumping power adjusted according to the pressure detection value; or, the actual pumping power is doubled compared to the pumping power adjusted according to the pressure detection value.

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