Device for multi-level pulse and substrate processing device including the same

Abstract

The present invention provides a multi-level pulse apparatus and a substrate processing apparatus including the same, which minimize power reflection when generating plasma using a radio frequency signal having multiple pulse levels. The apparatus includes: a radio frequency signal generator that generates a radio frequency signal having a first pulse level and a second pulse level that are different from each other; and a matching network that receives the radio frequency signal and provides a corresponding output signal to a load. The radio frequency signal generator generates the radio frequency signal such that a first target impedance for the first pulse level and a second target impedance for the second pulse level are different from each other.

Description

Technical Field

[0001] The present invention relates to a device for multi-level pulses and a substrate processing device comprising the same. Background Art

[0002] When manufacturing semiconductor devices or display devices, various processes utilizing plasma (e.g., etching, ashing, ion implantation, cleaning, etc.) may be used. Substrate processing devices utilizing plasma can be divided into capacitively coupled plasma (CCP) and inductively coupled plasma (ICP) types based on how the plasma is generated. In a CCP-type device, two electrodes are arranged facing each other in a chamber, and an electric field is formed in the chamber by applying a radio frequency (RF) signal to one or both of the two electrodes, thereby generating plasma. On the other hand, in an ICP-type device, one or more coils are provided in the chamber, and an electromagnetic field is induced in the chamber by applying an RF signal to the coils, thereby generating plasma. Summary of the Invention

[0003] Furthermore, plasma generation can use an RF signal with multiple pulse levels. For example, in the case of an RF signal with two pulse levels, power reflection can be minimized for one pulse level by matching the target impedance of the RF signal and the load impedance. However, for the other pulse level, matching the target impedance and the load impedance is difficult, making it difficult to minimize power reflection. This is because the time required to adjust the operating parameters (e.g., capacitance) of components (e.g., capacitors) in the matching circuit is longer than the duration of each RF signal pulse level.

[0004] The technical problem to be solved by the present invention is to provide an apparatus for multi-level pulses and a substrate processing apparatus including the same, which minimize power reflection when generating plasma using radio frequency signals having multiple pulse levels.

[0005] Another technical problem to be solved by the present invention is to provide a method for minimizing power reflection when generating plasma using a radio frequency signal having multiple pulse levels.

[0006] The technical problems of the present invention are not limited to the above technical problems, and those skilled in the art will clearly understand other technical problems not mentioned through the following description.

[0007] One aspect of the apparatus for multi-level pulses of the present invention for solving the above-mentioned technical problems includes: a radio frequency (RF) signal generator that generates an RF signal including a first pulse level and a second pulse level that are different from each other; and a matching network that receives the RF signal and provides a corresponding output signal to a load, wherein the RF signal generator generates the RF signal in such a manner that a first target impedance of the first pulse level and a second target impedance of the second pulse level are different from each other.

[0008] One aspect of the substrate processing apparatus of the present invention for solving the above-mentioned technical problems includes: a chamber including a processing space for processing a substrate; a support module located in the processing space and for supporting the substrate; a gas supply unit for supplying gas to the processing space; and a plasma generating unit for exciting the gas in the processing space into a plasma state, wherein the plasma generating unit includes: a radio frequency signal generator for generating an RF signal including a first pulse level and a second pulse level different from each other; and a matching network for receiving the RF signal and providing a corresponding output signal to a load, wherein the RF signal generator generates the radio frequency signal in such a manner that a first target impedance of the first pulse level and a second target impedance of the second pulse level are different from each other.

[0009] One aspect of the method for multi-level pulses of the present invention for solving the above-mentioned technical problems includes: receiving an RF signal of a first pulse level having a first frequency and a first target impedance; measuring a first load impedance of a load corresponding to the first pulse level; adjusting operating parameters of a tunable component to match the first target impedance and the first load impedance to minimize reflected power; receiving an RF signal of a second pulse level different from the first pulse level; measuring a second load impedance of the load corresponding to the second pulse level; and adjusting the second target impedance of the RF signal of the second pulse level to minimize reflected power.

[0010] Details of other embodiments are included in the detailed description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a block diagram of an apparatus for multi-level pulse according to an embodiment of the present invention.

[0012] Figure 2 Is used to illustrate the Figure 1 A view of an RF signal generated by an RF signal generator.

[0013] Figure 3 Is used to illustrate Figure 1 Circuit diagram of the matching circuit and nonlinear load.

[0014] Figure 4 is an exemplary diagram for explaining the relationship between the power level, frequency, and target impedance of an RF signal.

[0015] Figure 5 Show Figure 1 Example tuning range of the matching circuit for multiple pulse levels.

[0016] Figure 6 This is a Smith chart used to illustrate frequency tuning and target impedance tuning.

[0017] Figure 7 is a flow chart for illustrating a method for multi-level pulse according to an embodiment of the present invention.

[0018] Figure 8 is a block diagram for illustrating an apparatus for multi-level pulse according to another embodiment of the present invention.

[0019] Figure 9 is a block diagram for illustrating an apparatus for multi-level pulse according to yet another embodiment of the present invention.

[0020] Figure 10 is an exemplary cross-sectional view for explaining a substrate processing apparatus according to some embodiments of the present invention. DETAILED DESCRIPTION

[0021] Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Advantages and features of the present invention and methods for achieving these advantages and features will be described in detail with reference to the accompanying drawings. Figure 1 The present invention will become clear from the detailed description of the embodiments below. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in a variety of different forms. These embodiments are provided only to complete the disclosure of the present invention and to fully inform those skilled in the art of the present invention of the scope of the invention. The present invention is limited only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components.

[0022] When an element or layer is referred to as being “on” or “over” another element or layer, it not only includes being directly over the other element or layer but also includes other layers or other elements intervening. In contrast, when an element is referred to as being “directly on” or “over” another element, it means that there are no other elements or layers intervening.

[0023] Although the terms "first," "second," etc., are used to describe various elements, constituents, and / or parts, these elements, constituents, and / or parts are clearly not limited by these terms. These terms are only used to distinguish one element, constituent, and / or part from another element, constituent, and / or part. Therefore, the first element, first constituent, or first part mentioned below may also be the second element, second constituent, or second part within the technical concept of the present invention.

[0024] The terms used in this specification are intended to illustrate the embodiments and are not intended to limit the present invention. In this specification, unless otherwise specified in a sentence, the singular also includes the plural. The use of "comprises" and / or "comprising" in this specification does not exclude the presence or addition of one or more other constituent elements, steps, operations, and / or elements in addition to the mentioned constituent elements, steps, operations, and / or elements.

[0025] Figure 1 is a block diagram of an apparatus for multi-level pulse according to an embodiment of the present invention. Figure 2 Is used to illustrate the Figure 1 A view of an RF signal generated by an RF signal generator. Figure 3 Is used to illustrate Figure 1 Circuit diagram of the matching circuit and nonlinear load.

[0026] First, refer to Figure 1 , a device 1 for multi-level pulse according to an embodiment of the present invention includes an RF signal generator 10, a matching network 20, a nonlinear load 30, and the like.

[0027] The RF signal generator 10 generates an RF signal including a plurality of pulse levels. Figure 2 (a) The RF signal may include a first pulse level PL1 and a second pulse level PL2 that are different from each other. For example, the first pulse level PL1 may be greater than the second pulse level PL2. Alternatively, referring to Figure 2 (b) The RF signal may include a plurality of pulse levels PL11, PL12, PL13, and PL14 that are different from each other. As shown in the figure, the plurality of pulse levels PL11, PL12, PL13, and PL14 may decrease in sequence. Alternatively, referring to Figure 2 (c) The RF signal may include a plurality of pulse levels PL21, PL22, PL23 that are different from each other. As shown in the figure, the plurality of pulse levels PL21, PL22, PL23 may increase in sequence. Figure 2As shown, the RF signal may include more than five pulse levels, or may not increase / decrease in sequence. The following description will focus on the case where the RF signal includes two different first pulse levels PL1 and second pulse levels PL2 (see Figure 2 (a)).

[0028] Such an RF signal generator 10 may include a processor 12 , a power generator 14 , an impedance modulator 16 , a frequency modulator 18 , and a sensor 19 .

[0029] The power generator 14 generates power of an RF signal so that the RF signal has pulse levels PL1 and PL2 different from each other.

[0030] The impedance modulator 16 adjusts the target impedance of the RF signal. The impedance modulator 16 can adjust the target impedance differently depending on the pulse levels PL1 and PL2 of the RF signal. For example, when the RF signal includes a first pulse level PL1 and a second pulse level PL2, the impedance modulator 16 adjusts a first target impedance corresponding to the first pulse level PL1 and a second target impedance corresponding to the second pulse level PL2 to be different from each other. The first target impedance may be a preset value, and the second target impedance may be a value adjusted based on a second load impedance of a load corresponding to the second pulse level PL2.

[0031] The frequency modulator 18 adjusts the frequency of the RF signal. The frequency modulator 18 can adjust the frequency differently depending on the pulse levels PL1 and PL2 of the RF signal. For example, when the RF signal includes a first pulse level PL1 and a second pulse level PL2, the frequency modulator 18 adjusts a first frequency corresponding to the first pulse level PL1 and a second frequency corresponding to the second pulse level PL2 to be different from each other. Here, the second frequency can be adjusted based on a second load impedance of a load corresponding to the second pulse level PL2.

[0032] In summary, the RF signal at the first pulse level PL1 has a first frequency and corresponds to a first target impedance, where the first target impedance may be a pre-set value. Conversely, the second frequency or corresponding second target impedance of the RF signal at the second pulse level PL2 may be adjusted based on the second impedance of the load to minimize reflected power. In other words, the RF signal generator 10, which generates RF signals at multiple pulse levels PL1 and PL2, may adjust the characteristics of the RF signal (particularly the target impedance) to minimize reflected power. This will be discussed later. Figures 4 to 6 This will be explained in detail.

[0033] The sensor 19 measures the reflected power. When the impedances are matched, the reflected power is small, and when the impedances are mismatched, the reflected power is large.

[0034] The processor 12 controls the power generator 14 , the frequency modulator 18 , the impedance modulator 16 , the sensor 19 , and the like.

[0035] In addition, the matching network 20 performs an impedance matching operation, and such matching network 20 includes a matching circuit 22 , a controller 24 , a first sensor 28 , a second sensor 29 , and the like.

[0036] The matching circuit 22 includes a plurality of tunable components (eg, variable capacitors 22a, 22b (see Figure 3 )). The matching circuit 22 receives the RF signal provided from the RF signal generator 10 and provides the output signal to the nonlinear load 30. Figure 3 In FIG, an example of the matching circuit 22 includes a node N1 receiving an RF signal, a variable capacitor 22a arranged between the node N1 and the ground voltage, and a variable capacitor 22b arranged between the node N1 and the nonlinear load 30. Figure 3 In the embodiment, the matching circuit 22 is exemplarily described as including only two variable capacitors 22a and 22b, but the present invention is not limited thereto. For example, the matching circuit 22 may include three or more variable capacitors, or may further include an inductor.

[0037] The first sensor 28 measures the impedance of the non-linear load 30 associated with the RF signal generated by the RF signal generator 10. The load impedance Z L The plural representation of Z can be L =R L +jX L (R L represents the load resistance, X L Represents the load reactance, J 2 =-1). Through the first sensor 28, the load resistance R L and load reactance X L .

[0038] The second sensor 29 may measure characteristics (eg, target impedance) of the RF signal generated by the RF signal generator 10. Additionally, the second sensor 29 may also measure other characteristics of the RF signal (eg, at least one of power magnitude and frequency).

[0039] The controller 24 is based on the sensed value of the first sensor 28 (ie, the load impedance (load resistance R L and load reactance X L) and the sensed value of the second sensor 29 (i.e., power level, frequency, target impedance, etc.) to control the operating parameters (i.e., C1, C2) of the components (i.e., variable capacitors 22a, 22b). More specifically, the controller 24 may adjust the operating parameters C1, C2 of the components 22a, 22b for the first pulse level PL1 to achieve impedance matching, and may not adjust the operating parameters C1, C2 of the components 22a, 22b for the second pulse level PL2.

[0040] In summary, when an RF signal of a first pulse level PL1 having a first frequency and a first target impedance is provided to matching network 20, first sensor 28 measures the first load impedance, and second sensor 29 measures the first target impedance, power level, frequency, etc. of the RF signal. Based on these measurement data, controller 24 adjusts operating parameters C1 and C2 of tunable components 22a and 22b to minimize reflected power.

[0041] In contrast, when an RF signal at a second pulse level PL2, different from the first pulse level PL1, is input to the matching network 20, the controller 24 does not adjust the operating parameters C1 and C2 of the components 22a and 22b. In other words, the operating parameters C1 and C2 adjusted when the RF signal at the first pulse level PL1 was supplied are maintained. To minimize reflected power, the RF signal generator 10 adjusts the second target impedance of the RF signal at the second pulse level PL2. Additionally, the RF signal generator 10 adjusts the second frequency of the RF signal at the second pulse level PL2. Various methods can be used to adjust the second target impedance and / or second frequency. For example, when the controller 24 determines the second target impedance and / or second frequency that minimizes reflected power based on the sensed values ​​of the first sensor 28 and the second sensor 29, the controller 24 may provide the second target impedance and / or second frequency to the RF signal generator 10, causing the RF signal generator 10 to no longer adjust the second target impedance and / or second frequency. Alternatively, the controller 24 may provide the sensing values ​​of the first sensor 28 and the second sensor 29 to the processor 12, and the processor 12 calculates a second target impedance and / or a second frequency that can minimize the reflected power, and adjusts the second target impedance and / or the second frequency of the RF signal according to the calculation results.

[0042] Below, refer to Figure 4 The characteristics of the RF signal generated in the above-described manner will be described. Figure 4 is an exemplary diagram for explaining the relationship between the power level, frequency, and target impedance of an RF signal.

[0043] Reference Figure 4The RF signal includes a first pulse level PL1 and a second pulse level PL2 that are different from each other. During time t1-t2 and t3-t4, the RF signal may be at the first pulse level PL1, and during time 0-t1, t2-t3, and t4-t5, the RF signal may be at the second pulse level PL2 that is lower than the first pulse level PL1.

[0044] Here, during time t1-t2 and t3-t4, the frequency of the RF signal may be a first frequency Freq1, and during time 0-t1, t2-t3, and t4-t5, the frequency of the RF signal may be a second frequency Freq2 smaller than the first frequency Freq1.

[0045] In addition, during time t1-t2 and t3-t4, the target impedance of the RF signal may be a first target impedance Imp1, and during time 0-t1, t2-t3, and t4-t5, the target impedance of the RF signal may be a second target impedance Imp2 smaller than the first target impedance Imp1.

[0046] As described above, when the RF signal is at the first pulse level PL1, the first target impedance Imp1 of the RF signal is a preset (or fixed) value and is not adjusted in real time to match the load impedance. Reflected power is minimized by adjusting the operating parameters C1 and C2 of the components 22a and 22b of the matching circuit 22. The first frequency Freq1 of the RF signal can also be adjusted.

[0047] Conversely, when the RF signal is at the second pulse level PL2, the second frequency Freq2 and the second target impedance Imp2 of the RF signal may be adjusted in real time to match the load impedance. Minimization of reflected power is not achieved by adjusting the operating parameters C1 and C2 of the components 22a and 22b of the matching circuit 22.

[0048] the following, Figure 5 and Figure 6 FIG. 1 is a diagram for explaining the effect of the apparatus for multi-level pulse according to an embodiment of the present invention. Figure 5 Show Figure 1 Example tuning range of the matching circuit for multiple pulse levels. Figure 6 This is a Smith chart used to illustrate frequency tuning and target impedance tuning.

[0049] First, in Figure 5710, when the RF signal is at the first pulse level PL1, power reflection can be minimized by adjusting operating parameters C1 and C2 of components 22a and 22b of matching circuit 22 and / or adjusting the frequency of the RF signal. It can be seen that at frequency f1, power reflection is equal to 0.

[0050] In contrast, referring to reference numeral 721, when the RF signal is at the second pulse level PL2, it is difficult to minimize power reflection even by adjusting the operating parameters C1 and C2 of the components 22a and 22b of the matching circuit 22 or adjusting the frequency of the RF signal. It can be seen that power reflection is not zero even at the frequency f21.

[0051] Here, refer to Figure 6 To explain specifically, it is assumed that the area indicated by the small square is the load impedance Impi when the RF signal is at the second pulse level PL2.

[0052] Even if the frequency of the RF signal is adjusted (i.e., frequency tuning), the real part of the impedance (i.e., the load resistance R L ) is also the same, and only the imaginary part of the impedance (i.e., the load reactance X L )change.

[0053] When the RF signal is at the second pulse level PL2, impedance changes based on frequency tuning of the RF signal can only be achieved along the trajectory FT. Even if the RF signal frequency is adjusted, the impedance only moves along the trajectory FT and does not reach the load impedance Impi. Therefore, even if frequency tuning is performed, matching consistency cannot be improved.

[0054] On the contrary, refer to Figure 5 Referring to reference numeral 720, when the RF signal is at the second pulse level PL2, if the target impedance corresponding to the RF signal is adjusted and the frequency is selectively adjusted, the power reflection can be minimized. As shown in the figure, it can be seen that at frequency f2, the power reflection is equal to 0.

[0055] Refer again Figure 6 When the RF signal is at the second pulse level PL2, if the target impedance corresponding to the RF signal is adjusted, the impedance change tuned according to the RF signal frequency can be achieved on the trajectory IT (i.e., from FT to IT). Therefore, when the RF signal frequency is adjusted, the impedance can be moved on the trajectory IT to reach the load impedance Impi. This improves matching consistency.

[0056] Figure 7 is a flow chart for illustrating a method for multi-level pulse according to an embodiment of the present invention. Figures 1 to 6 The features described are mainly described based on the different features.

[0057] Reference Figure 1 and Figure 7 , the matching network 20 receives an RF signal ( S610 ).

[0058] The second sensor 29 of the matching network 20 measures the characteristics of the RF signal. As a result of the measurement, it is determined whether the RF signal is at the second pulse level PL2 (S620).

[0059] If it is not the second pulse level PL2 (ie, if it is the first pulse level PL1), the first sensor 28 measures the load impedance Z L (S630).

[0060] The operating parameters (i.e., C1, C2) of the tunable components (i.e., variable capacitors 22a, 22b) for minimizing the reflected power are determined and adjusted (S640). Specifically, the controller 24 determines and adjusts the operating parameters (i.e., C1, C2) of the tunable components (i.e., variable capacitors 22a, 22b) for minimizing the reflected power based on the sensed value of the first sensor 28 (i.e., the load impedance (load resistance R L and load reactance X L )) and the sensing values ​​of the second sensor 29 (ie, power size, frequency and target impedance, etc.) are used to determine and adjust the operating parameters (ie, C1, C2) of the components (ie, variable capacitors 22a, 22b).

[0061] On the contrary, if it is the second pulse level PL2, the first sensor 28 measures the load impedance Z L (S650).

[0062] A target impedance and / or frequency for minimizing reflected power is determined and adjusted (S660). Specifically, the RF signal generator 10 may adjust the second target impedance and / or second frequency of the RF signal at the second pulse level PL2. Various methods can be used to adjust the second target impedance and / or second frequency. For example, when the controller 24 determines the second target impedance and / or second frequency that minimizes reflected power based on the sensed values ​​of the first sensor 28 and the second sensor 29, the controller 24 may provide the second target impedance and / or second frequency to the RF signal generator 10, causing the RF signal generator 10 to no longer adjust the second target impedance and / or second frequency. Alternatively, the controller 24 may provide the sensed values ​​of the first sensor 28 and the second sensor 29 to the processor 12, which then calculates the second target impedance and / or second frequency that minimizes reflected power and adjusts the target impedance and / or frequency of the RF signal based on the calculated value.

[0063] Assuming that the first pulse level PL1 and the second pulse level PL22 are alternately input to the matching network 20 , the operation is as follows.

[0064] Matching network 20 receives an RF signal of a first pulse level PL1 having a first frequency and a first target impedance. Next, a first load impedance of the load corresponding to first pulse level PL1 is measured, and operating parameters of the tunable component are adjusted to match the first target impedance and the first load impedance to minimize reflected power.

[0065] Next, an RF signal of a second pulse level PL2 different from the first pulse level PL1 is received, a second load impedance corresponding to the second pulse level PL2 is measured, and a second target impedance and / or a second frequency of the RF signal of the second pulse level PL2 are adjusted to minimize reflected power.

[0066] Figure 8 FIG. 1 is a block diagram illustrating an apparatus for multi-level pulse according to another embodiment of the present invention. Figures 1 to 7 The features described are mainly described based on the different features.

[0067] Reference Figure 8 In the apparatus 2 for multi-level pulse according to another embodiment of the present invention, the RF signal generator 10 may include a processor 12, a power generator 14, an impedance modulator 16, and a sensor 19. That is, the RF signal generator 10 may not include a frequency modulator (refer to Figure 1 18). Therefore, the RF signal generator 10 generates an RF signal including a first pulse level and a second pulse level different from each other. When performing impedance matching for the first pulse level, the operating parameters (e.g., C1, C2) of the matching circuit 22 may be used, and when performing impedance matching for the second pulse level, target impedance tuning may be used without using the matching circuit 22.

[0068] Figure 9 1 is a block diagram for illustrating a device for multi-level pulse according to another embodiment of the present invention. Figures 1 to 8 The features described are mainly described based on the different features.

[0069] Reference Figure 9 In the apparatus 3 for multi-level pulses according to yet another embodiment of the present invention, the RF signal generator 10 may provide data 19a related to the RF signal in addition to providing the RF signal to the matching network 20. The provision of the data 19a may be performed in real time. The data 19a may include the power level or frequency of the RF signal.

[0070] In the device 1 for multi-level pulse according to an embodiment of the present invention, the second sensor of the matching network 20 (refer to Figure 1 29) measures the characteristics of the RF signal (eg, power level, frequency, etc.), and the controller (referring to Figure 1 24 ) reflects the sensed value measured by the second sensor 29 to control the operating parameters (ie, C1 , C2 ) of the component (ie, the variable capacitors 22 a , 22 b ).

[0071] On the contrary, Figure 9 As shown, when the data 19a related to the RF signal is directly transferred to the matching network 20, the sensing time of the second sensor 29 is not required, and the sensing error caused by the second sensor 29 does not occur. Figure 1 24) can adjust operating parameters (ie, C1, C2) faster and more accurately based on the received data 19a.

[0072] Figure 10 is an exemplary cross-sectional view for explaining a substrate processing apparatus according to some embodiments of the present invention. Figure 10 A substrate processing apparatus that generates plasma using an ICP method is exemplarily shown, but the invention is not limited thereto.

[0073] Reference Figure 10 According to some embodiments of the present invention, a substrate processing apparatus 10' processes a substrate W using plasma. For example, the substrate processing apparatus 10' may perform an etching process on the substrate W. The substrate processing apparatus 10' may include a process chamber 100, a support unit 200, a gas supply unit 300, a plasma generating unit 400, and a baffle unit 500.

[0074] The process chamber 100 provides a space for performing a substrate treating process and includes a housing 110 , a sealing cover 120 , and a liner 130 .

[0075] The housing 110 has a space inside thereof with an open upper surface. The interior space of the housing 110 is provided as a processing space for performing a substrate processing process. The housing 110 is made of a metal material. The housing 110 can be made of an aluminum material. The housing 110 can be grounded. An exhaust hole 102 is formed on the bottom surface of the housing 110. The exhaust hole 102 is connected to an exhaust line 151. Reaction byproducts generated during the process and gases remaining in the interior space of the housing can be discharged to the outside through the exhaust line 151. Through the exhaust process, the interior of the housing 110 is depressurized to a predetermined pressure.

[0076] The sealing cover 120 covers the opened upper surface of the housing 110. The sealing cover 120 is provided in the shape of a plate and seals the inner space of the housing 110. The sealing cover 120 may include a dielectric substance.

[0077] The gasket 130 is disposed inside the housing 110. It is formed inside the space with open top and bottom surfaces. The gasket 130 can be cylindrical in shape. The gasket 130 can have a radius corresponding to the inner side of the housing 110. The gasket 130 is disposed along the inner surface of the housing 110. A support ring 131 is formed at the upper end of the gasket 130. The support ring 131 is a ring-shaped plate that protrudes outward along the circumference of the gasket 130. The support ring 131 is placed at the upper end of the housing 110 and supports the gasket 130. The gasket 130 can be made of the same material as the housing 110. That is, the gasket 130 can be made of aluminum. The gasket 130 protects the inner surface of the housing 110. During the process of energizing the process gas, arc discharge may occur inside the chamber 100. Arc discharge can damage surrounding equipment. The gasket 130 protects the inner surface of the housing 110, thereby preventing damage to the inner surface of the housing 110 from arc discharge. Furthermore, it prevents impurities generated during the substrate processing process from being deposited on the inner wall of the housing 110. Compared to the housing 110, the gasket 130 is inexpensive and easy to replace. Therefore, if the gasket 130 is damaged by arc discharge, the operator can replace it with a new one.

[0078] The substrate support unit 200 is located inside the housing 110. The substrate support unit 200 supports the substrate W. The substrate support unit 200 may include an electrostatic chuck 210 that attracts the substrate W using electrostatic force. Alternatively, the substrate support unit 200 may support the substrate W using various methods, such as mechanical clamping. The support unit 200 including the electrostatic chuck 210 will be described below.

[0079] The substrate supporting unit 200 includes an electrostatic chuck 210, an insulating plate 250, and a lower cover 270. The substrate supporting unit 200 may be spaced upward from a bottom surface of the housing 110 inside the process chamber 100.

[0080] The electrostatic chuck 210 includes a dielectric plate 220 , a lower electrode 223 , a heater 225 , a support plate 230 , and a focus ring 240 .

[0081] A dielectric plate 220 is located at the upper end of the electrostatic chuck 210. The dielectric plate 220 is a disc-shaped dielectric substance. A substrate W is placed on the upper surface of the dielectric plate 220. The upper surface of the dielectric plate 220 has a radius smaller than that of the substrate W. Therefore, the edge region of the substrate W is located outside the dielectric plate 220. A first supply flow path 221 is formed in the dielectric plate 220. The first supply flow paths 221 are provided from the upper surface to the bottom surface of the dielectric plate 220. The plurality of first supply flow paths 221 are spaced apart from each other and provide passages for supplying a heat transfer medium to the bottom surface of the substrate W.

[0082] A lower electrode 223 and a heater 225 are embedded within the dielectric plate 220. The lower electrode 223 is located above the heater 225. The lower electrode 223 is electrically connected to a first lower power source 223a. The first lower power source 223a comprises a DC power source. A switch 223b is provided between the lower electrode 223 and the first lower power source 223a. The lower electrode 223 can be electrically connected to the first lower power source 223a by turning the switch 223b on and off. When the switch 223b is turned on, a DC current is applied to the lower electrode 223. Due to the current applied to the lower electrode 223, an electrostatic force acts between the lower electrode 223 and the substrate W, and the substrate W is attracted to the dielectric plate 220 by the electrostatic force.

[0083] The heater 225 is electrically connected to the second lower power source 225a. The heater 225 generates heat by resisting the current applied from the second lower power source 225a. The generated heat is transferred to the substrate W through the dielectric plate 220. The heat generated in the heater 225 maintains the substrate W at a predetermined temperature. The heater 225 includes a spiral coil.

[0084] Support plate 230 is positioned below dielectric plate 220. The bottom surface of dielectric plate 220 and the top surface of support plate 230 may be bonded together using an adhesive. Support plate 230 may be made of aluminum. The top surface of support plate 230 may be stepped so that the center region of the top surface of support plate 230 is higher than the edge regions. The center region of the top surface of support plate 230 has an area corresponding to the bottom surface of dielectric plate 220 and is bonded to the bottom surface of dielectric plate 220. Support plate 230 includes a first circulation flow path 231, a second circulation flow path 232, and a second supply flow path 233.

[0085] The support plate 230 may include a metal plate. The support plate 230 may be connected to the high-frequency power supply 620 via a high-frequency transmission line 610. Power may be applied from the high-frequency power supply 620 to the support plate 230 so that the plasma generated in the processing space is smoothly supplied to the substrate W. That is, the support plate 230 may function as an electrode. Figure 10 In the embodiment, the substrate processing apparatus 10' is configured as an ICP type, but the present invention is not limited thereto. The substrate processing apparatus 10' according to one embodiment of the present invention may be configured as a CCP type. When the substrate processing apparatus 10' is configured as a CCP type, the high-frequency transmission line 610 may be connected to the lower electrode for generating plasma so that power is applied from the high-frequency power supply 620 to the lower electrode.

[0086] The first circulation flow path 231 is provided as a channel for the circulation of the heat transfer medium. The first circulation flow path 231 may be formed in a spiral shape within the support plate 230. Alternatively, the first circulation flow path 231 may be arranged so that annular flow paths having different radii have the same center. The first circulation flow paths 231 may be connected to each other. The first circulation flow paths 231 are formed at the same height.

[0087] The second circulation flow path 232 is provided as a channel for circulating a cooling fluid. The second circulation flow path 232 may be formed in a spiral shape within the support plate 230. Furthermore, the second circulation flow paths 232 may be arranged so that annular flow paths having different radii have the same center. Each second circulation flow path 232 may be interconnected. The second circulation flow paths 232 may have a larger cross-sectional area than the first circulation flow path 231. The second circulation flow paths 232 may be formed at the same height. The second circulation flow paths 232 may be located below the first circulation flow path 231.

[0088] Second supply channels 233 extend upward from first circulation channels 231 and are provided on the upper surface of support plate 230. Second supply channels 233 are provided in a number corresponding to the number of first supply channels 221 and connect first supply channels 221 and first circulation channels 231.

[0089] The first circulation flow path 231 is connected to the heat transfer medium storage unit 231a via a heat transfer medium supply line 231b. The heat transfer medium storage unit 231a stores a heat transfer medium. The heat transfer medium includes an inert gas. Depending on the embodiment, the heat transfer medium may include helium (He) gas. Helium gas is supplied to the first circulation flow path 231 via the heat transfer medium supply line 231b and then sequentially passes through the second supply flow path 233 and the first supply flow path 221 to the bottom surface of the substrate W. The helium gas serves as a medium for transferring heat transferred from the plasma to the substrate W to the electrostatic chuck 210.

[0090] The second circulation flow path 232 is connected to the cooling fluid storage unit 232a via a cooling fluid supply line 232c. The cooling fluid storage unit 232a stores cooling fluid. A cooler 232b may be provided in the cooling fluid storage unit 232a. The cooler 232b cools the cooling fluid to a predetermined temperature. Alternatively, the cooler 232b may be provided on the cooling fluid supply line 232c. The cooling fluid supplied to the second circulation flow path 232 via the cooling fluid supply line 232c circulates along the second circulation flow path 232, thereby cooling the support plate 230. While the support plate 230 itself is cooled, it also cools the dielectric plate 220 and the substrate W, thereby maintaining the substrate W at a predetermined temperature.

[0091] The focus ring 240 is disposed at the edge of the electrostatic chuck 210. The focus ring 240 has a ring shape and is disposed along the circumference of the dielectric plate 220. The upper surface of the focus ring 240 may be stepped so that the outer portion 240a of the upper surface of the focus ring 240 is higher than the inner portion 240b. The inner portion 240b of the upper surface of the focus ring 240 is located at the same height as the upper surface of the dielectric plate 220. The inner portion 240b of the upper surface of the focus ring 240 supports the edge of the substrate W located outside the dielectric plate 220. The outer portion 240a of the focus ring 240 is disposed so as to surround the edge of the substrate W. The focus ring 240 concentrates plasma in the area facing the substrate W in the process chamber 100.

[0092] The insulating plate 250 is located below the support plate 230. The insulating plate 250 has a cross-sectional area corresponding to that of the support plate 230. The insulating plate 250 is located between the support plate 230 and the lower cover 270. The insulating plate 250 is made of an insulating material and electrically insulates the support plate 230 from the lower cover 270.

[0093] The lower cover 270 is located at the lower end of the substrate support unit 200. The lower cover 270 is spaced upward from the bottom surface of the housing 110. A space is formed within the lower cover 270, the upper surface of which is open. The upper surface of the lower cover 270 is covered by the insulating plate 250. Therefore, the outer radius of the cross-section of the lower cover 270 can be the same as the outer radius of the insulating plate 250. A lift pin module (not shown) and the like for moving the transported substrate W from an external transport component to the electrostatic chuck 210 can be located within the interior space of the lower cover 270.

[0094] The lower cover 270 includes a connecting member 273. The connecting member 273 connects the outer surface of the lower cover 270 to the inner wall of the housing 110. A plurality of connecting members 273 may be arranged at regular intervals on the outer surface of the lower cover 270. The connecting member 273 supports the substrate support unit 200 within the process chamber 100. Furthermore, the connecting member 273 is connected to the inner wall of the housing 110, electrically grounding the lower cover 270. A first power supply line 223c connected to the first lower power source 223a, a second power supply line 225c connected to the second lower power source 225a, a heat transfer medium supply line 231b connected to the heat transfer medium storage unit 231a, and a cooling fluid supply line 232c connected to the cooling fluid storage unit 232a extend through the interior space of the connecting member 273 to the inner side of the lower cover 270.

[0095] The gas supply unit 300 supplies process gas to the interior of the process chamber 100. The gas supply unit 300 includes a gas supply nozzle 310, a gas supply line 320, and a gas storage unit 330. The gas supply nozzle 310 is disposed in the central portion of the sealing cover 120. An injection port is formed on the bottom surface of the gas supply nozzle 310. The injection port is located at the lower portion of the sealing cover 120 and supplies process gas to the processing space inside the process chamber 100. The gas supply line 320 connects the gas supply nozzle 310 and the gas storage unit 330. The gas supply line 320 supplies the process gas stored in the gas storage unit 330 to the gas supply nozzle 310. A valve 321 is provided on the gas supply line 320. The valve 321 opens or closes the gas supply line 320 and adjusts the flow rate of the process gas supplied through the gas supply line 320.

[0096] The plasma generating unit 400 excites the process gas in the process chamber 100 into a plasma state. According to one embodiment of the present invention, the plasma generating unit 400 may be configured as an ICP type.

[0097] The plasma generating unit 400 may include a high frequency power supply device 420, a first antenna 411, a second antenna 413, and a power distributor 430. The high frequency power supply device 420 provides a high frequency signal (ie, an RF signal). Figures 1 to 9 An RF signal generator 10 and a matching network 20 are illustrated.

[0098] The first antenna 411 and the second antenna 413 are connected in series with the high-frequency power supply 420. The first antenna 411 and the second antenna 413 can each be configured as a coil wound into multiple turns. The first antenna 411 and the second antenna 413 are electrically connected to the high-frequency power supply 420 to receive RF power. The power distributor 430 distributes the power supplied from the high-frequency power supply 420 to the first antenna 411 and the second antenna 413.

[0099] The first antenna 411 and the second antenna 413 may be arranged at a position opposite to the substrate W. For example, the first antenna 411 and the second antenna 413 may be arranged at the upper portion of the process chamber 100. The first antenna 411 and the second antenna 413 may be arranged in a ring shape. In this case, the radius of the first antenna 411 may be smaller than the radius of the second antenna 413. In addition, the first antenna 411 may be located on the upper inner side of the process chamber 100, and the second antenna 413 may be located on the upper outer side of the process chamber 100.

[0100] According to an embodiment, the first antenna 411 and the second antenna 413 may also be disposed on the side of the process chamber 100. According to an embodiment, either the first antenna 411 or the second antenna 413 may be disposed on the upper portion of the process chamber 100, and the other may be disposed on the side of the process chamber 100. As long as multiple antennas generate plasma in the process chamber 100, the positions of the coils are not limited.

[0101] The first antenna 411 and the second antenna 413 may induce a time-varying electromagnetic field in the chamber by receiving RF power from the high frequency power supply 420 , and thereby, the process gas supplied to the process chamber 100 may be excited into plasma.

[0102] The baffle unit 500 is located between the inner sidewall of the housing 110 and the substrate support unit 200. The baffle unit 500 includes a baffle having a through-hole formed therein. The baffle is annular in shape. Process gas supplied into the housing 110 passes through the through-holes of the baffle and is exhausted through the exhaust hole 102. The flow of the process gas can be controlled by the shape of the baffle and the through-hole.

[0103] While the embodiments of the present invention have been described above with reference to the accompanying drawings, it should be understood by those skilled in the art that the present invention can be implemented in other specific forms without changing its technical concept or essential features. Therefore, it should be understood that the embodiments described above are illustrative in all respects and are not restrictive.

Claims

1. A device for multi-level pulses, comprising: a radio frequency signal generator for generating a radio frequency signal including a first pulse level and a second pulse level different from each other; as well as A matching network receives the radio frequency signal and provides a corresponding output signal to the load. wherein the RF signal generator generates the RF signal in such a manner that a first target impedance of the first pulse level and a second target impedance of the second pulse level are different from each other; The matching network includes a tunable component, the matching network adjusts the operating parameters of the component for the first pulse level to achieve impedance matching, does not adjust the operating parameters of the component for the second pulse level, and adjusts the second target impedance of the RF signal generator for the second pulse level.

2. The device for multi-level pulse according to claim 1, wherein The first target impedance is a preset value, and The second target impedance is adjusted according to a second load impedance of the load corresponding to the second pulse level.

3. The device for multi-level pulse according to claim 1, wherein The radio frequency signal generator generates the radio frequency signal in such a manner that a first frequency of the first pulse level and a second frequency of the second pulse level are different from each other.

4. The device for multi-level pulse according to claim 3, wherein: The second frequency is adjusted according to a second load impedance of the load corresponding to the second pulse level.

5. The device for multi-level pulse according to claim 1, wherein The RF signal generator transmits the power level or frequency of the RF signal to the matching network in real time.

6. The device for multi-level pulse according to claim 1, wherein The radio frequency signal generator comprises: a power generator for generating power of the radio frequency signal; A frequency modulator, configured to adjust the frequency of the radio frequency signal; an impedance modulator, adjusting a second target impedance of the radio frequency signal; and A processor controls the power generator, the frequency modulator, and the impedance modulator.

7. The device for multi-level pulse according to claim 1, wherein The matching network includes: matching circuits, including tunable components; a first sensor, sensing the impedance of the load; a second sensor for sensing at least one of a first target impedance and a second target impedance of the radio frequency signal; and A controller controls an operating parameter of the component based on the sensed values ​​of the first sensor and the second sensor.

8. The device for multi-level pulse according to claim 7, wherein The second sensor also measures at least one of power magnitude and frequency of the radio frequency signal.

9. A substrate processing device comprising: a chamber including a processing space for processing a substrate; a supporting module, located in the processing space and configured to support the substrate; a gas supply unit for supplying gas to the processing space; as well as The plasma generating unit excites the gas in the processing space into a plasma state, Wherein, the plasma generating unit comprises: a radio frequency signal generator, generating a radio frequency signal; and A matching network receives the radio frequency signal and provides a corresponding output signal to the load. wherein the RF signal generator generates the RF signal in such a manner that a first target impedance of a first pulse level of the RF signal and a second target impedance of a second pulse level of the RF signal are different from each other; The matching network includes a tunable component, the matching network adjusts the operating parameters of the component for the first pulse level to achieve impedance matching, does not adjust the operating parameters of the component for the second pulse level, and adjusts the second target impedance of the RF signal generator for the second pulse level.

10. The substrate processing apparatus according to claim 9, wherein: The radio frequency signal generator generates the radio frequency signal in such a manner that a first frequency of the first pulse level and a second frequency of the second pulse level are different from each other.

11. The substrate processing apparatus according to claim 10, wherein: The second target impedance and the second frequency are adjusted according to a second load impedance of the load corresponding to the second pulse level.

12. The substrate processing apparatus according to claim 9, wherein: The radio frequency signal generator comprises: a power generator for generating power of the radio frequency signal; A frequency modulator, configured to adjust the frequency of the radio frequency signal; an impedance modulator, adjusting a second target impedance of the radio frequency signal; and A processor controls the power generator, the frequency modulator, and the impedance modulator.

13. The substrate processing apparatus according to claim 9, wherein: The matching network includes: matching circuits, including tunable components; a first sensor, sensing the impedance of the load; a second sensor for sensing at least one of a first target impedance and a second target impedance of the radio frequency signal; and A controller controls an operating parameter of the component based on the sensed values ​​of the first sensor and the second sensor.

14. A method for multi-level pulses, comprising the steps of: receiving a radio frequency signal of a first pulse level having a first frequency and a first target impedance; measuring a first load impedance of a load corresponding to the first pulse level; adjusting an operating parameter of a tunable component to match the first target impedance and the first load impedance to minimize reflected power; receiving a radio frequency signal having a second pulse level different from the first pulse level; measuring a second load impedance of the load corresponding to the second pulse level; as well as The operating parameters of the component are adjusted for the first pulse level to achieve impedance matching, and for the second pulse level, no adjustment is performed on the operating parameters of the component, and a second target impedance of the radio frequency signal of the second pulse level is adjusted to minimize reflected power.

15. The method for multi-level pulse according to claim 14, further comprising the steps of: The frequency of the radio frequency signal of the second pulse level is adjusted to minimize reflected power.

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