TW202119530A - Method applied to a plasma processing system and plasma processing system - Google Patents

Abstract

A method applied to a plasma processing system for process. The plasma processing system includes a first chamber with a first bottom electrode and a second chamber with a second bottom electrode. The RF source generates a first and a second bias voltage at the first and second bottom electrodes, respectively. The method includes: when the first and second workpieces are processed simultaneously and respectively in the first and second chambers, the first plasma feature of the plasma in the first chamber is detected by a first detection device, and the second plasma feature of the plasma in the second chamber is detected by a second detection device; the first plasma feature and the second plasma feature are adjusted according to the first bias voltage and/or a second bias voltage such that the relative deviation between the first and second plasma feature is less than the predetermined value.

Description

Method for processing using plasma processing system and plasma processing system

The present invention relates to a method and relates to the technical field of semiconductor processing. In detail, it is a method for processing a plasma processing system and a plasma processing system.

Traditional plasma processing systems have multiple chambers to process multiple work pieces (such as wafers) at the same time. However, in the absence of a precise sensing mechanism, it is difficult to maintain the same process conditions between the various chambers, resulting in poor consistency of the process results of the work pieces (such as wafers). In addition, when only a single chamber of the multiple chambers has work pieces (such as wafers) to be processed, the difference in gas expansion and power distribution between the chamber with work pieces (such as wafers) and other chambers Due to differences and other reasons, the process results of a work piece (such as a wafer) manufactured by a single chamber processed separately and the process results of a work piece (such as a wafer) manufactured by multiple chambers processed at the same time are inconsistent.

The invention discloses a method for processing a plasma processing system and a plasma processing system. For example, when multiple chambers are processed at the same time, the consistency of the processing results of a work piece (such as a wafer) can still be maintained.

According to an embodiment of the present invention, a method for processing using a plasma processing system is disclosed. The plasma system includes a first chamber and a second chamber. A first lower electrode is disposed in the first chamber. A second lower electrode is arranged in the second chamber, and a radio frequency source supplies power to the first lower electrode and the second lower electrode through a matching circuit and a power divider, so that the first lower electrode generates a first bias. The setting voltage and the second bottom electrode generate a second bias voltage. The method includes: when the first chamber is processing a first work piece and the second chamber is processing a second work piece at the same time, detecting plasma in the first chamber by a first detection device A first plasma characteristic of the plasma, and a second plasma characteristic of the plasma in the second chamber is detected by a second detection device; and the adjustment of the plasma characteristic according to the first plasma characteristic and the second plasma characteristic The first bias voltage and/or the second bias voltage are used to make the relative deviation of the first plasma characteristic and the second plasma characteristic smaller than a preset value.

According to an embodiment of the present invention, a plasma processing system is disclosed. The plasma processing system includes a first chamber, a second chamber, a first detection device, a second detection device, and a control device. A first lower electrode is arranged in the first chamber and a second lower electrode is arranged in the second chamber; a radio frequency source supplies power to the first lower electrode and the second lower electrode through a matching circuit and a power divider, respectively , So that the first bottom electrode generates a first bias voltage and the second bottom electrode generates a second bias voltage. The first detection device is used for detecting a first plasma characteristic of the plasma in the first chamber, wherein the first plasma characteristic is related to the first bias voltage. The second detection device is used for detecting a second plasma characteristic of the plasma in the second chamber, wherein the second plasma characteristic is related to the second bias voltage. The control device is used for processing a first work piece in the first chamber and simultaneously processing a second work piece in the second chamber, according to the first plasma characteristic and the second plasma characteristic The first bias voltage and/or the second bias voltage are adjusted so that the relative deviation between the first plasma characteristic and the second plasma characteristic is smaller than a preset value.

Through the method and plasma processing system disclosed in the present invention, it is possible to maintain the consistency of the process results of the work piece (such as wafer) when the work piece (such as wafer) is processed in multiple chambers at the same time.

The following disclosure provides many different embodiments or examples of different components for implementing the disclosure. Specific examples of components and configurations are described below to simplify the disclosure. Of course, these are only examples and are not intended to be limiting. For example, in the following description, a first member formed on or on a second member may include an embodiment in which the first member and the second member are formed in direct contact, and may also include additional members therein An embodiment that can be formed between the first member and the second member so that the first member and the second member may not directly contact. In addition, the present disclosure may repeat reference numbers and/or letters in each example. This repetition is for the purpose of simplification and clarity and does not in itself indicate the relationship between the various embodiments and/or configurations discussed.

In addition, for ease of description, spatially relative terms such as "below", "below", "below", "above", "upper" and the like can be used herein to describe one element or component and another(s) The relationship between components or components is illustrated in the figure. Spatial relative terms are intended to cover different orientations of devices in use or operation other than those depicted in the figures. The device can be oriented in other ways (rotated by 90 degrees or in other orientations) and therefore the spatial relative descriptors used in this article can also be interpreted.

Although the numerical ranges and parameters stated in the broad scope of this disclosure are approximate values, the numerical values stated in the specific examples should be reported as accurately as possible. However, any value inherently contains certain errors inevitably due to the standard deviation seen in the respective test measurement. Furthermore, as used herein, the term "about" generally means within 10%, 5%, 1%, or 0.5% of a given value or range. Alternatively, the term "approximately" means within one acceptable standard error of the mean when considered by a general technician of the technology. Except in the operation/working example, or unless explicitly specified in other ways, such as the total numerical range of the quantity of materials disclosed in this article, the duration of time, temperature, operating conditions, the ratio of quantities and the like, Quantities, values and percentages should be understood as modified by the term "about" in all examples. Correspondingly, unless otherwise indicated, the numerical parameters stated in the scope of this disclosure and the accompanying invention application are approximate values that can be changed as needed. At the very least, each numerical parameter should be explained at least in view of the number of significant digits reported and by applying ordinary rounding techniques. Ranges can be expressed herein as from one endpoint to the other or between two endpoints. All ranges disclosed herein include endpoints, unless otherwise specified.

Traditional plasma processing systems have multiple chambers (such as two chambers) to process multiple wafers at the same time. However, due to factors such as chamber assembly differences, component design differences, and component service life differences, in the absence of precise sensing mechanisms, it is difficult to maintain the same process conditions between the chambers, resulting in consistent wafer process results Poor. In addition, in actual situations, each batch of wafers usually has an odd number of wafers (such as 25). Therefore, when the plasma processing system has two chambers, a single wafer will be processed separately. Processing. When only a single chamber of the multiple chambers has wafers to be processed, the difference in gas expansion and power distribution between the chamber with wafers and other chambers makes the single-chamber processed The process result of the wafer is inconsistent with the process result of the wafer manufactured by the simultaneous processing of multiple chambers. Therefore, the present invention discloses a plasma processing system and a processing method applied to the plasma processing system to avoid the above-mentioned problem of poor consistency.

FIG. 1 is a schematic diagram of a plasma processing system 1 according to an embodiment of the present invention. The plasma processing system 1 includes chambers 11 and 21, a bottom electrode 12 placed in the chamber 11, a bottom electrode 22 placed in the chamber 21, detection devices 13 and 23, a control device 30, a power distributor 40, and a radio frequency Source 51, matching circuit 52 and storage device 60. When there are working parts (such as wafers) in the chambers 11 and 21 at the same time, the plasma processing system 1 uses plasma to process the working parts (such as wafers) in the chambers 11 and 21 at the same time; when the chamber 11 and 21 When only one of them (such as chamber 11) has a work piece (such as wafer) and the other (such as chamber 21) does not have a work piece (such as wafer), the plasma processing system 1 uses plasma to treat the chamber 11 Inside the work piece (such as wafer) for processing. In some embodiments, the plasma processing system 1 is an etching device for etching a work piece (such as a wafer). In some embodiments, the plasma processing system 1 is a thin film deposition device for performing thin film deposition on a work piece (such as a wafer). For example, the plasma processing system 1 may be a physical vapor deposition device. The present invention does not limit the type of plasma processing system 1.

The bottom electrodes 12 and 22 are used to carry work pieces (such as wafers). In detail, when a work piece (such as a wafer) is introduced into the chambers 11 and 21, the work piece (such as a wafer) is placed on the lower electrodes 12 and 22, so that the plasma processing system 1 treats the work piece through plasma. (Such as wafers) for processing. The detection device 13 includes a first end 131, a second end 132, and a third end 133. The first end 131 is coupled to the chamber 11, the second end 132 is coupled to the control device 30, and the third end 133 is coupled to the storage.装置60。 Device 60. The detection device 13 is used to detect the first plasma characteristic of the plasma in the chamber 11. In this embodiment, the detection device 13 is an optical emission spectroscopy (OES) for detecting the first plasma characteristic of the plasma in the chamber 11. In this embodiment, the first plasma characteristic is the characteristic peak intensity of the plasma in the chamber 11. The detection device 23 includes a first end 231 and a second end 232. The first end 231 is coupled to the chamber 21, and the second end 232 is coupled to the control device 30. The detection device 23 is used to detect the second plasma characteristic of the plasma in the chamber 21. In this embodiment, the detection device 23 is an optical emission spectrometer for detecting the second plasma characteristic of the plasma in the chamber 21. In this embodiment, the second plasma characteristic is the characteristic peak intensity of the plasma in the chamber 21.

The radio frequency source 51 is used to transmit radio frequency power through the matching circuit 52. The matching circuit 52 is used to match the impedance behind the radio frequency source 51 so that the radio frequency power output by the radio frequency source 51 has the maximum coupling efficiency. The power divider 40 includes a first terminal 401, a second terminal 402, a third terminal 403, and a fourth terminal 404. The first terminal 401 is coupled to the control device 30, and the second terminal 402 is coupled to the lower electrode 12 and the third terminal. The terminal 403 is coupled to the lower electrode 22, and the fourth terminal 404 is coupled to the matching circuit 52. The power distributor 40 is used to distribute the radio frequency power generated by the radio frequency source 51 to the lower electrode 12 and the lower electrode 22 so that the lower electrode 12 has a first bias voltage and the lower electrode 22 has a second bias voltage. The first bias voltage is related to the first plasma characteristic of the plasma in the chamber 11, and the second bias voltage is related to the second plasma characteristic of the plasma in the chamber 21. For example, the first bias voltage on the bottom electrode 12 has a positive correlation with the characteristic peak intensity of the plasma in the chamber 11. In other words, the greater the voltage of the first bias voltage, the characteristic peak of the plasma in the chamber 11 The stronger the intensity. However, this is not a limitation of the present invention, and the present invention does not limit the relationship between the bias voltage and the plasma characteristics to be a positive correlation.

It should be noted that, in the above-mentioned embodiment, the plasma processing system 1 has two chambers (ie, chambers 11 and 21) to process work pieces (such as wafers) at the same time. However, this is not a limitation of the present invention. In other embodiments, the plasma processing system 1 may have multiple chambers to process work pieces (such as wafers) at the same time, which still belongs to the scope of the present invention.

Referring to FIG. 2, FIG. 2 is a schematic diagram of a power divider 40 according to an embodiment of the present invention. The power divider 40 includes capacitors C1 and C2. One end of the capacitor C1 is coupled to the bottom electrode 12 through the second terminal 402, and the other end of the capacitor C1 is coupled to the matching circuit 52 through the fourth terminal 404. One end of the capacitor C2 is coupled to the bottom electrode 22 through the third terminal 403, and the other end of the capacitor C2 is coupled to the matching circuit 52 through the fourth terminal 404. After receiving the RF power from the RF source 51 and the matching circuit 52, the power divider 40 distributes the RF power to the lower electrodes 12 and 22 coupled to the capacitors C1 and C2 through the impedance formed by the capacitors C1 and C2 to generate a bias voltage. The control device 30 transmits a control signal through the first terminal 401 of the power divider 40, thereby adjusting the states of the capacitors C1 and C2, thereby adjusting the first bias voltage and/or the second bias voltage. The control device 30 adjusts the states of the capacitors C1 and C2 through the control signal, and then adjusts the first bias voltage and/or the second bias voltage. The detailed description will be described in subsequent paragraphs.

It should be noted that the power divider 40 may include a stepping motor (not shown), and the stepping motor is used to adjust the capacitors C1 and C2 according to the control signal transmitted by the control device 30.

1 again, one end of the storage device 60 is coupled to the third end 133 of the detection device 13, and the other end of the storage device 60 is coupled to the control device 30. The control device 30 includes a first end 301, a second end 302, a third end 303, a fourth end 304, and a fifth end 305, wherein the first end 301 is coupled to the chamber 11, and the second end 302 is coupled to the chamber 21. The third end 303 is coupled to the first end 401 of the power divider 40, the fourth end 304 is coupled to the second end 132 of the detection device 13, and the fifth end 305 is coupled to the second end 232 of the detection device 23 .

When the control device 30 determines that the chambers 11 and 12 have working parts (such as wafers) at the same time, the control device 30 transmits the first control signal CTRL1 to the power divider 40 to make the power divider 40 operate in the first mode; and, control The device 30 controls and starts the radio frequency source 51 so that the radio frequency source 51 transmits radio frequency power to the power divider 40 through the matching circuit 52. It should be noted that the present invention does not limit the control device 30 to control the activation of the radio frequency source 51. In other embodiments, after the control device 30 transmits the first control signal CTRL1 to the power divider 40 so that the power divider 40 operates in the first mode, the radio frequency source 51 may be manually activated, so that the radio frequency source 51 passes through the matching circuit 52 The radio frequency power is transmitted to the power divider 40.

In this embodiment, the control device 30 can detect whether the chambers 11 and 12 have working parts (such as wafers) through sensors. For example, an infrared sensor can be used to detect whether there is a work piece (such as a wafer) on the bottom electrodes 12 and 22. For another example, a pressure sensor can be used to detect whether a work piece (such as a wafer) is placed on the lower electrodes 12 and 22, and then it can be determined whether the chamber 11 and 12 has a work piece (such as a wafer). For another example, the control device 30 can determine whether the robot arm of the plasma processing system 1 transfers work pieces (such as wafers) into the chambers 11 and 12, thereby determining whether the chambers 11 and 12 have work pieces ( Such as wafers). The present invention does not limit the judgment mechanism of the control device 30.

In detail, when the control device 30 controls the power divider 40 to operate in the first mode, at least one of the capacitor C1 and the capacitor C2 is adjusted to a state in which the capacitance value can be adjusted. For example, as shown in FIG. 3A, when the control device 30 controls the power divider 40 to operate in the first mode, the capacitor C1 and the capacitor C2 are adjusted to a state where the capacitance value can be adjusted. Under such a setting, the radio frequency source 51 is activated (for example, activated by the control device 30 autonomously or manually) to start processing the work pieces (such as wafers) in the chambers 11 and 21. Next, the radio frequency source 51 transmits radio frequency power to the power divider 40 through the matching circuit 52, and the power divider 40 distributes the power to the lower electrodes 12 and 22 through the impedance formed by the capacitor C1 and the capacitor C2, thereby on the lower electrode 12 A first bias voltage is generated, and a second bias voltage is generated on the bottom electrode 22. The detection device 13 detects the first plasma characteristic of the plasma in the chamber 11, and the detection device 23 detects the second plasma characteristic of the plasma in the chamber 21.

Next, the control device 30 receives the detected first plasma feature and the second plasma feature from the detection device 13 and the detection device 23, and outputs the second control signal CTRL2 to the power according to the first plasma feature and the second plasma feature. The divider 40 enables the power divider 40 to adjust the capacitance values of the capacitor C1 and the capacitor C2 at the same time according to the second control signal CTRL2, so as to change the impedance ratio of the capacitor C1 and the capacitor C2. As the impedance ratio of the capacitor C1 and the capacitor C2 changes, the power distributed to the lower electrode 12 and the lower electrode 22 changes accordingly, which in turn causes the first bias voltage and the second bias voltage to change. Moreover, due to the change of the first bias voltage and the second bias voltage, the first plasma characteristic related to the first bias voltage and the second plasma characteristic related to the second bias voltage will also change accordingly.

In detail, after receiving the first plasma characteristic and the second plasma characteristic, the control device 30 determines whether the relative deviation value of the first plasma characteristic and the second plasma characteristic is less than a preset value to generate the second control signal CTRL2. In this embodiment, the first plasma characteristic is the characteristic peak intensity D ₁ (λ) of the plasma in the chamber 11, and the second plasma characteristic is the characteristic peak intensity D ₂ (λ) of the plasma in the chamber 21. The control device 30 judges whether the characteristic peak intensity of the plasma in the chambers 11 and 21 satisfies the following formula: [D ₁ (λ)- D ₂ (λ)]/[D ₁ (λ)+ D ₂ (λ)]< 1%

If the relative deviation of the characteristic peak intensity D ₁ (λ) and the characteristic peak intensity D ₂ (λ) is greater than 1%, it means that there is a difference in the process conditions between the chambers 11 and 21. Therefore, the power divider 40 is controlled according to the second control The signal CTRL2 adjusts the capacitance value of the capacitor C1 until _{the relative deviation between the characteristic peak intensity D 1} (λ) and the characteristic peak intensity D ₂ (λ) is less than 1%.

Since the total radio frequency power generated by the radio frequency source 51 is a fixed value, the equivalent impedance ratio between the capacitor C1 and the capacitor C2 will determine the power distributed to the lower electrodes 12 and 22. In an embodiment, when the characteristic peak intensity D ₁ (λ) is less than the characteristic peak intensity D ₂ (λ), and _{the relative deviation between the characteristic peak intensity D 1} (λ) and the characteristic peak intensity D ₂ (λ) is greater than 1% At this time, the power divider 40 increases the capacitance value of the capacitor C1 according to the second control signal CTRL2, so that the equivalent impedance of the capacitor C1 is reduced. When the total radio frequency power generated by the radio frequency source 51 is a fixed value and the capacitor C2 is not adjusted, the equivalent impedance of the capacitor C1 decreases, so that the power allocated to the lower electrode 12 will increase accordingly and the power allocated to the lower electrode 22 will increase accordingly. The power is correspondingly reduced, so that the characteristic peak intensity D ₁ (λ) increases and the characteristic peak intensity D ₂ (λ) decreases. The power divider 40 will continue to cyclically operate until _{the relative deviation between the characteristic peak intensity D 1} (λ) and the characteristic peak intensity D ₂ (λ) is less than 1%.

Those with ordinary knowledge in the art should be able to easily understand that as long as the equivalent impedance ratio between the capacitor C1 and the capacitor C2 can be adjusted, the capacitance value of the capacitor C1 is not limited to reduce the characteristic peak intensity D ₁ (λ) and the characteristic peak intensity The difference of D ₂ (λ). Take another example, when the characteristic peak intensity D ₁ (λ) is less than the characteristic peak intensity D ₂ (λ), and _{the relative deviation between the characteristic peak intensity D 1} (λ) and the characteristic peak intensity D ₂ (λ) is greater than 1. When %, the power divider 40 reduces the capacitance value of the capacitor C2 according to the second control signal CTRL2, so that the equivalent impedance of the capacitor C2 increases. When the total radio frequency power generated by the radio frequency source 51 is a constant value and the capacitor C1 is not adjusted, the increase in the equivalent impedance of the capacitor C2 will cause the power allocated to the lower electrode 12 to increase accordingly and the power allocated to the lower electrode 22 will increase accordingly. The power is correspondingly reduced, so that the characteristic peak intensity D ₁ (λ) is increased and the characteristic peak intensity D ₂ (λ) is reduced, and the power divider 40 will continue to operate cyclically until the characteristic peak intensity D ₁ (λ) and the characteristic peak intensity The relative deviation of D ₂ (λ) is less than 1%.

Take another example, when the characteristic peak intensity D ₁ (λ) is less than the characteristic peak intensity D ₂ (λ), and _{the relative deviation between the characteristic peak intensity D 1} (λ) and the characteristic peak intensity D ₂ (λ) is greater than 1. When %, the power divider 40 simultaneously increases the capacitance value of the capacitor C1 and decreases the capacitance value of the capacitor C2 according to the second control signal CTRL2, so that the equivalent impedance of the capacitor C1 decreases and the equivalent impedance of the capacitor C2 increases. In the case that the total radio frequency power generated by the radio frequency source 51 is a fixed value, the reduction of the equivalent impedance of the capacitor C1 and the increase of the equivalent impedance of the capacitor C2 will cause the power allocated to the lower electrode 12 to increase accordingly and to be allocated to the lower electrode 12. The power of the electrode 22 is correspondingly reduced, so that the characteristic peak intensity D ₁ (λ) is increased and the characteristic peak intensity D ₂ (λ) is reduced, and the power divider 40 will continue to cyclically operate until the characteristic peak intensity D ₁ (λ) is equal to The relative deviation of the characteristic peak intensity D ₂ (λ) is less than 1%. Since the capacitances C1 and C2 are adjusted at the same time _{, the difference between the characteristic peak intensity D 1} (λ) and the characteristic peak intensity D ₂ (λ) will decrease more quickly.

In the above embodiments, the characteristic peak intensity D ₁ (λ) is smaller than the characteristic peak intensity D ₂ (λ) as an example. Those with ordinary knowledge in the art should be able to easily understand after reading the above embodiments, the characteristic peak intensity D ₁ (λ) is greater than the characteristic peak intensity D ₂ (λ) and _{the relative deviation between the characteristic peak intensity D 1} (λ) and the characteristic peak intensity D ₂ (λ) is greater than 1%. The operation of the power divider 40 is described in detail here Omit to save space.

It should be noted that in the process of adjusting the capacitance values of the capacitor C1 and the capacitor C2, the control device 30 also transmits a signal to the storage device 60 to control the value of the first plasma characteristic of the plasma in the storage device 60 in the storage chamber 11 .

In the embodiment of FIG. 3A, when the control device 30 controls the power divider 40 to operate in the first mode, the capacitor C1 and the capacitor C2 are adjusted to a state where the capacitance value can be adjusted. However, this is not a limitation of the present invention. As shown in FIG. 3B, when the control device 30 controls the power divider 40 to operate in the first mode, the capacitor C1 is adjusted to a state where the capacitance value can be adjusted, and the capacitor C2 is adjusted to a state where the capacitance value is fixed and cannot be adjusted, thereby It is avoided that when the capacitance value of the capacitor C1 is adjusted, the capacitance value of the capacitor C2 is floating so that the power divider 40 spends more time adjusting the first plasma characteristic and the second plasma characteristic.

When the control device 30 controls the power divider 40 to operate in the first mode, the present invention does not limit the capacitance value of the capacitor C2 when it is fixed. Under such a setting, the radio frequency source 51 is activated (for example, activated by the control device 30 autonomously or manually) to start processing the work pieces (such as wafers) in the chambers 11 and 22. Next, the radio frequency source 51 transmits radio frequency power to the power divider 40 through the matching circuit 52, and the power divider 40 distributes the power to the lower electrodes 12 and 22 through the impedance formed by the capacitor C1 and the capacitor C2, thereby on the lower electrode 12 A first bias voltage is generated, and a second bias voltage is generated on the bottom electrode 22. The detection device 13 detects the first plasma characteristic of the plasma in the chamber 11, and the detection device 23 detects the second plasma characteristic of the plasma in the chamber 21.

Next, the control device 30 receives the detected first plasma feature and the second plasma feature from the detection device 13 and the detection device 23, and outputs the second control signal CTRL2 to the power according to the first plasma feature and the second plasma feature. The divider 40 enables the power divider 40 to adjust the capacitance value of the capacitor C1 according to the second control signal CTRL2. In detail, when the capacitance value of the capacitor C1 is adjusted, since the impedance ratio of the capacitor C1 and the capacitor C2 is changed, the power distributed to the lower electrode 12 and the lower electrode 22 changes accordingly, so that the first bias voltage and the second bias voltage are changed accordingly. Set the voltage to change. Moreover, due to the change of the first bias voltage and the second bias voltage, the first plasma characteristic related to the first bias voltage and the second plasma characteristic related to the second bias voltage also change accordingly.

The operation of the embodiment shown in FIG. 3B is only different. Among the capacitors C1 and C2, only the capacitor C1 is adjusted to a state where the capacitance value is adjustable. Those skilled in the art should be able to easily read the embodiment of FIG. 3A after reading the embodiment of FIG. 3A. It is understood that as long as the power distributed to the lower electrodes 12 and 22 can be changed by adjusting the impedance ratio of the capacitor C1 and the capacitor C2, the same goal can be achieved. The remaining operations of the embodiment shown in FIG. 3B are omitted here to save space.

The plasma processing system 1 proposed by the present invention uses an optical emission spectrometer to sense the first plasma characteristics and the second plasma characteristics of the plasma in the chambers 11 and 21, and is based on the plasma characteristics in the chambers 11 and 21. The first plasma characteristic and the second plasma characteristic are used to adjust the impedance ratio of the capacitor C1 and the capacitor C2 in the power divider 40, thereby adjusting the process conditions in the chambers 11 and 21 to be close to the same, so as to improve the simultaneous in the cavity The consistency of the process results of the work pieces (such as wafers) processed in the chambers 11 and 21.

As mentioned above, in actual situations, each batch of wafers usually has an odd number of wafers, so in the end, a single wafer is processed separately. When the control device 30 determines that only one of the chambers 11 and 12 has a work piece (such as a wafer), for example, only the chamber 11 has a work piece (such as a wafer), and the chamber 21 is not working In the case of a wafer (such as a wafer), the control device 30 transmits the first control signal CTRL1 to the power divider 40 so that the power divider 40 operates in the second mode. In addition, the control device 30 controls and activates the radio frequency source 51 so that the radio frequency source 51 transmits radio frequency power to the power divider 40 through the matching circuit 52. It should be noted that the present invention does not limit the activation of the radio frequency source 51 to be controlled by the control device 30. In other embodiments, after the control device 30 transmits the first control signal CTRL1 to the power divider 40 so that the power divider 40 operates in the second mode, the radio frequency source 51 can be manually activated, so that the radio frequency source 51 passes through the matching circuit. 52 transmits radio frequency power to the power divider 40.

In this embodiment, the control device 30 can detect whether the chambers 11 and 12 have working parts (such as wafers) through sensors. For example, an infrared sensor can be used to detect whether there is a work piece (such as a wafer) on the bottom electrodes 12 and 22. For another example, a pressure sensor can be used to detect whether a work piece (such as a wafer) is placed on the lower electrodes 12 and 22, and then it can be determined whether the chamber 11 and 12 has a work piece (such as a wafer). For another example, the control device 30 can determine whether the robot arm of the plasma processing system 1 transfers work pieces (such as wafers) into the chambers 11 and 12, thereby determining whether the chambers 11 and 12 have work pieces ( Such as wafers). The present invention does not limit the judgment mechanism of the control device 30.

In detail, when the control device 30 controls the power divider 40 to operate in the second mode, the capacitor C1 is adjusted to a state where the capacitance value can be adjusted, and the capacitor C2 is adjusted to a state where the capacitance value is the minimum value, and the minimum value makes the matching The electrical path between the circuit 52 and the lower electrode 22 is regarded as an open circuit, as shown in FIG. 4A. When the capacitor C2 is adjusted to the state where the capacitance value is the minimum value, the power distributed to the lower electrode 22 via the power divider 40 will be fixed or even close to zero. Under such a setting, the radio frequency source 51 is activated (for example, activated by the control device 30 autonomously or manually) to start processing the work pieces (such as wafers) in the chambers 11 and 21. Next, the radio frequency source 51 transmits radio frequency power to the power divider 40 through the matching circuit 52, and the power divider 40 distributes the power to the lower electrodes 12 and 22 through the impedance formed by the capacitor C1 and the capacitor C2, thereby on the lower electrode 12 A first bias voltage is generated, and a second bias voltage is generated on the bottom electrode 22. The detection device 13 detects the first plasma characteristic of the plasma in the chamber 11.

Then, the control device 30 receives the previously stored first plasma characteristic value from the storage device 60, and obtains the average value of the first plasma characteristic according to the stored first plasma characteristic value. The control device 30 generates a third control signal CTRL3 according to the average value of the first plasma characteristics, and transmits the third control signal CTRL3 to the power divider 40. The power divider 40 adjusts the capacitance value of the capacitor C1 according to the third control signal CTRL3, so that the first bias voltage is changed. And, as the first bias voltage changes, the first plasma characteristics related to the first bias voltage also change accordingly.

The real-time adjustment of the capacitance value of the capacitor C1 by the average value of the first plasma characteristic will make the first plasma characteristic of the plasma in the chamber 11 more consistent with the previously stored average value of the first plasma characteristic. In turn, when only a single chamber (such as chamber 11) is used to process workpieces (such as wafers), the process result obtained is consistent with multiple chambers (such as chambers 11 and 21) at the same time. The consistency of the process results of the processing of work pieces (such as wafers) is similar.

In the embodiment of FIG. 4A, the capacitor C2 is adjusted to the state where the capacitance value is the minimum, so that the power distributed to the lower electrode 22 through the power divider 40 will be fixed or even close to zero, thereby increasing the adjustment cavity. The stability of the first plasma characteristic of the plasma in the chamber 11. However, this is not a limitation of the present invention. In other embodiments, other technical means may be used to improve the stability of the first plasma characteristic of the plasma in the adjustment chamber 11.

Referring to FIG. 4B, in the embodiment of FIG. 4B, the electrical path between the matching circuit 52 and the lower electrode 22 has a switch SW. When the control device 30 determines that only one of the chambers 11 and 12 has a work piece (such as a wafer), for example, only the chamber 11 has a work piece (such as a wafer), and the chamber 21 does not have a work piece (Such as a wafer), the control device 30 transmits the first control signal CTRL1 to the power divider 40 so that the power divider 40 operates in the second mode. When the control device 30 controls the power divider 40 to operate in the second mode, the capacitor C1 is adjusted to a state where the capacitance value can be adjusted, and the switch SW is disabled, so that an electrical path between the matching circuit 52 and the lower electrode 22 is formed The circuit breaks, so that the power distributed to the lower electrode 22 via the power distributor 40 approaches zero, and the stability of the first plasma characteristic of the plasma in the adjustment chamber 11 is improved.

It should be noted that in the embodiment of FIG. 4B, the switch SW is located between the terminal 403 and the lower electrode 22. However, this is not a limitation of the present invention. Those skilled in the art should easily understand that the switch SW can be located at any position on the electrical path between the matching circuit 52 and the lower electrode 22.

FIG. 5A is a flowchart of the first part of the method 5 applied to the plasma processing system 1 according to an embodiment of the present invention. Provided that substantially the same result can be obtained, the present invention is not limited to completely follow the steps of the process shown in FIG. 5A. The process steps of the first part are roughly summarized as follows. Step 501: The process starts. Step 502: Determine whether the first chamber has a first work piece and the second chamber has a second work piece, if yes, go to step 503; otherwise, continue with the flowchart of FIG. 5C. Step 503: Perform processing. Step 504: Use the first detection device to detect the first plasma characteristic of the plasma in the first chamber. Step 505: Use the second detection device to detect the second plasma characteristic of the plasma in the second chamber. Step 506: Adjust the first bias voltage and/or the second bias voltage according to the first plasma characteristic and the second plasma characteristic, so that the relative deviation between the first plasma characteristic and the second plasma characteristic is smaller than a preset value value.

FIG. 5B is a detailed flowchart of step 506 in FIG. 5A according to an embodiment of the present invention. Provided that substantially the same results can be obtained, the present invention does not limit the execution to completely follow the process steps shown in FIG. 5B. The detailed process steps of step 506 are roughly summarized as follows. Step 5061: Store the first plasma feature. Step 5062: Set at least one of the first capacitor and the second capacitor to a state where the capacitance value can be adjusted. Step 5063: Adjust the first capacitor and/or the second capacitor to adjust the first bias voltage and/or the second bias voltage. Step 5064: Determine whether the relative deviation value of the first plasma characteristic and the second plasma characteristic is less than the preset value, if yes, go to step 5065; otherwise, go to step 5063. Step 5065: the process ends.

FIG. 5C is a flowchart of the second part of the method 5 applied to the plasma processing system 1 according to an embodiment of the present invention. As long as the same result can be obtained roughly, the present invention is not limited to completely follow the process steps shown in FIG. 5C. The process steps of the second part are roughly summarized as follows. Step 507: Determine whether the first chamber has the first work piece and the second chamber does not have the second work piece, if yes, go to step 508; otherwise, go to step 510. Step 508: Obtain an average value of the first plasma characteristic according to the stored value of the first plasma characteristic. Step 509: Adjust the first bias voltage with the above average value as the target, so that the first plasma characteristic during the processing of the first work piece by only the first chamber is maintained at the above average value. Step 510: The process ends.

FIG. 5D is a detailed flowchart of step 509 in FIG. 5C according to an embodiment of the present invention. Provided that substantially the same result can be obtained, the present invention is not limited to completely follow the process steps shown in FIG. 5D. The detailed process steps of step 509 are roughly summarized as follows. Step 5091: Set the first capacitor to a state where the capacitance value can be adjusted, and set the second capacitor to a minimum capacitance value. Step 5092: Adjust the first capacitor to adjust the first bias voltage. Step 5093: Determine whether the first plasma characteristic is the above average value, if yes, go to step 5094; otherwise, go to step 5092. Step 5094: The process ends.

Those with ordinary knowledge in the art should be able to easily understand the detailed operation of method 5 after reading the embodiments in FIGS. 1 to 4B. The detailed description is omitted here to save space. In the embodiment of FIG. 1, the storage device 60 can also be used to store a program code. After the program code is read from the storage device 60 and executed, the control device 30 executes the process steps of the method 5.

FIG. 6 is a schematic diagram of a plasma processing system 1'according to an embodiment of the present invention. The plasma processing system 1'includes chambers 11' and 21', a bottom electrode 12' placed in the chamber 11', a bottom electrode 22' placed in the chamber 21', a power distributor 40', and a radio frequency The source 51', the matching circuit 52', the storage device 60', the judgment module 61, the detection module 62, and the control module 63, in which the chambers 11' and 21', the lower electrodes 12' and 22', the power distributor 40', and the radio frequency The source 51 ′, the matching circuit 52 ′, and the storage device 60 ′ are the same as the corresponding components in FIG. 1, and the detailed connection relationship and functions are omitted here to save space.

The judging module 61 is used for judging whether there are working parts (such as wafers) in the chamber 11 ′ and the chamber 21 ′ at the same time. The detection module 62 is used to detect the first plasma feature of the plasma in the chamber 11' and the second plasma feature of the plasma in the detection chamber 21', wherein the first plasma feature is above the lower electrode 12' The second plasma characteristic is related to the second bias voltage above the lower electrode 22'. The control module 63 is configured to adjust the first bias voltage and/or the second bias voltage according to the first plasma characteristic and the second plasma characteristic, so that the relative deviation between the first plasma characteristic and the second plasma characteristic is less than default value. Those skilled in the art should be able to easily understand after reading the above-mentioned embodiments that the judgment module 61 and the detection module 62 are used to execute the process steps of the method 5 shown in FIG. 5, and the detailed description is omitted here to save space.

It should be noted that the present invention does not limit the implementation of the judgment module 61, the detection module 62, and the control module 63. In detail, the judgment module 61, the detection module 62, and the control module 63 can be implemented by software, hardware, or firmware. For example, the detection module 62 can be implemented by hardware, such as the above-mentioned optical emission spectrometer, or software, such as a programming language.

The foregoing content summarizes the features of several embodiments, so that those familiar with the art can better understand the aspect of the disclosure. Those familiar with the technology should understand that they can easily use the present disclosure as a basis for designing or modifying other processes and structures for implementing the same purpose and/or achieving the same advantages of the embodiments described herein. Those familiar with this technology should also understand that these equivalent structures do not depart from the spirit and scope of this disclosure, and they can make various changes, substitutions and alterations in this article without departing from the spirit and scope of this disclosure.

1,1’: Plasma processing system 11,11’,21,21’: Chamber 12,12’,22,22’: Lower electrode 13,23: detection device 30: control device 40,40’: Power divider 51,51’: RF source 52, 52’: matching circuit 60,60’: storage device 131: The first end of the detection device 13 132: The second end of the detection device 13 133: The third end of the detection device 13 231: The first end of the detection device 23 232: The second end of the detection device 23 301: The first end of the control device 30 302: The second end of the control device 30 303: The third end of the control device 30 304: The fourth end of the control device 30 305: The fifth end of the control device 30 401: The first end of the power divider 40 402: The second end of the power divider 40 403: The third end of the power divider 40 404: The fourth end of the power divider 40 C1, C2: Capacitance 5: method 501-506, 5061-5065, 507-510, 5091-5094: steps 61: Judgment module 62: detection module 63: control module

When read in conjunction with the accompanying drawings, the aspect of the present disclosure is best understood from the following detailed description. It should be noted that according to standard practice in the industry, the various components are not drawn to scale. In fact, the size of various components can be increased or decreased arbitrarily for the sake of clarity of the discussion. FIG. 1 is a schematic diagram of a plasma processing system according to an embodiment of the present invention. Fig. 2 is a schematic diagram of a power divider according to an embodiment of the present invention. FIG. 3A is a schematic diagram of the power divider operating in the first mode according to an embodiment of the present invention. FIG. 3B is a schematic diagram of the power divider operating in the first mode according to another embodiment of the present invention. 4A is a schematic diagram of a power divider operating in a second mode according to an embodiment of the invention. 4B is a schematic diagram of the power divider operating in the second mode according to another embodiment of the present invention. FIG. 5A is a first partial flowchart of a method applied to a plasma processing system according to an embodiment of the present invention. FIG. 5B is a detailed flowchart of step 506 in FIG. 5A according to an embodiment of the present invention. FIG. 5C is a second partial flowchart of a method applied to a plasma processing system according to an embodiment of the present invention. FIG. 5D is a detailed flowchart of step 509 in FIG. 5C according to an embodiment of the present invention. FIG. 6 is a schematic diagram of a plasma processing system according to another embodiment of the present invention.

1: Plasma processing system

11, 21: Chamber

12, 22: Lower electrode

13,23: detection device

30: control device

40: power divider

51: RF source

52: matching circuit

60: storage device

131: The first end of the detection device 13

132: The second end of the detection device 13

133: The third end of the detection device 13

231: The first end of the detection device 23

232: The second end of the detection device 23

301: The first end of the control device 30

302: The second end of the control device 30

303: The third end of the control device 30

304: The fourth end of the control device 30

305: The fifth end of the control device 30

401: The first end of the power divider 40

402: The second end of the power divider 40

403: The third end of the power divider 40

404: The fourth end of the power divider 40

Claims (15)

A method for processing using a plasma processing system. The plasma system includes a first chamber and a second chamber. A first lower electrode is provided in the first chamber, and a second lower electrode is provided in the second chamber. Electrode, a radio frequency source supplies power to the first lower electrode and the second lower electrode through a matching circuit and a power divider, so that the first lower electrode generates a first bias voltage and the second lower electrode generates a The second bias voltage, wherein the method includes: When the first chamber is processing a first work piece and the second chamber is processing a second work piece at the same time, a first detection device is used to detect a first part of the plasma in the first chamber. Plasma characteristics, detecting a second plasma characteristic of the plasma in the second chamber by a second detection device; Adjust the first bias voltage and/or the second bias voltage according to the first plasma characteristic and the second plasma characteristic to make a relative deviation between the first plasma characteristic and the second plasma characteristic The value is less than a preset value; The first plasma characteristic is the characteristic peak intensity of the first plasma, and the second plasma characteristic is the characteristic peak intensity of the second plasma. The method according to claim 1, wherein in the process of processing the first work piece in the first chamber and simultaneously processing the second work piece in the second chamber, the first plasma characteristic is stored Numerical value. The method according to claim 2, wherein when only the first chamber is processing the first work piece, the average value of the first plasma characteristic is obtained according to the stored value of the first plasma characteristic, The first bias voltage is adjusted with the average value as the target, so that the first plasma characteristic during the processing of the first work piece by the first chamber is maintained at the average value. The method of claim 3, wherein the power divider includes a first capacitor, one end of the first capacitor is coupled to the first bottom electrode, and the other end of the first capacitor is coupled to the matching circuit; When the first chamber is processing the first work piece and the second chamber is processing the second work piece at the same time, the first capacitor is set to an adjustable state; by adjusting the first capacitor, To adjust the first bias voltage. The method according to claim 4, wherein the power divider further includes a second capacitor, one end of the second capacitor is coupled to the second bottom electrode, and the other end of the second capacitor is coupled to the matching circuit; When the first chamber is processing the first work piece and the second chamber is processing the second work piece at the same time, the power divider is in a first mode, the first capacitor and the second capacitor Both are set to a state where the capacitance value can be adjusted; by adjusting the first capacitance and/or the second capacitance, the first bias voltage and/or the second bias voltage are adjusted. The method according to claim 5, wherein when only the first chamber is processing the first work piece, the power divider is in a second mode, and the first capacitor is set to a state where the capacitance value can be adjusted, The second capacitor is set to a minimum capacitance value, where the minimum value makes an electrical path between the matching circuit and the second lower electrode regarded as an open circuit; by adjusting the first capacitor, the first capacitor is The bias voltage is adjusted. The method according to any one of claims 1 to 6, wherein the first detection device and the second detection device are an Optical Emission Spectroscopy (OES). The method according to any one of claims 1 to 6, further comprising: Determine whether the first chamber has the first work piece and whether the second chamber has the second work piece; When the first chamber has the first work piece and the second chamber has the second work piece, the first chamber processes the first work piece and the second chamber processes the second work piece Parts are processed at the same time; and When the first cavity has the first work piece and the second cavity does not have the second work piece, only the first cavity processes the first work piece. A plasma processing system, including: A first chamber and a second chamber; a first lower electrode is arranged in the first chamber and a second lower electrode is arranged in the second chamber; A radio frequency source supplies power to the first lower electrode and the second lower electrode through a matching circuit and a power divider, so that the first lower electrode generates a first bias voltage and the second lower electrode generates a second Two bias voltage; A first detection device for detecting a first plasma characteristic of the plasma in the first chamber, the first plasma characteristic being related to the first bias voltage; A second detection device for detecting a second plasma characteristic of the plasma in the second chamber, the second plasma characteristic being related to the second bias voltage; and A control device for processing a first work piece in the first chamber and processing a second work piece in the second chamber at the same time, according to the characteristics of the first plasma and the second plasma Feature adjusting the first bias voltage and/or the second bias voltage so that a relative deviation value between the first plasma feature and the second plasma feature is smaller than a preset value; The first plasma characteristic is a characteristic peak intensity of the first plasma, and the second plasma characteristic is a characteristic peak intensity of the second plasma. The plasma processing system according to claim 9, further comprising: A storage device is used for storing a value of the first plasma characteristic when the first chamber is processing the first work piece and the second chamber is processing the second work piece at the same time. The plasma processing system according to claim 10, wherein the control device is further used for processing the first workpiece according to the first plasma characteristic stored in the storage device when only the first chamber is processing the first work piece. The numerical value obtains an average value of the first plasma characteristic, and the first bias voltage is adjusted with the average value as a target. The plasma processing system according to claim 11, wherein the power divider includes a first capacitor, one end of the first capacitor is coupled to the first bottom electrode, and the other end of the first capacitor is coupled to the matching Circuit When the first chamber is processing the first work piece and the second chamber is processing the second work piece at the same time, the first capacitor is in an adjustable state; the control device adjusts the second work piece. A capacitor to adjust the first bias voltage. The plasma processing system according to claim 12, wherein the power divider further includes a second capacitor, one end of the second capacitor is coupled to the second bottom electrode, and the other end of the second capacitor is coupled to the second bottom electrode. Matching circuit When the first chamber is processing the first work piece and the second chamber is processing the second work piece at the same time, the power divider is in a first mode, the first capacitor and the second capacitor Both are in a state where the capacitance value can be adjusted; the control device adjusts the first bias voltage and/or the second bias voltage by adjusting the first capacitance and/or the second capacitance. The plasma processing system according to claim 13, wherein when only the first chamber is processing the first work piece, the power divider is in a second mode, and the first capacitor has an adjustable capacitance value State, the capacitance value of the second capacitor is a minimum value, where the minimum value makes an electrical path between the matching circuit and the second lower electrode regarded as a disconnection; the control device adjusts the first capacitor to correct The first bias voltage is adjusted. The plasma processing system according to any one of claims 9 to 14, wherein the first detection device and the second detection device are an optical emission spectroscopy (OES).

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