Plasma generator and use method thereof
By designing the shower head unit and the DC pulse generation module in the plasma generator, the problem of insufficient plasma uniformity is solved, and the pattern formation of fine patterns and high aspect ratios is achieved, which improves the uniformity of etching and deposition.
Patent Information
- Application Number
- CN202411161281.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-09-04
- Filing Date
- 2024-08-22
- Publication Date
- 2025-03-04
AI Technical Summary
During semiconductor manufacturing, the plasma is insufficient uniformity, resulting in uneven etching and deposition, affecting pattern fineness and depth-to-face ratio.
A plasma generator is designed, including a vacuum chamber, a source electrode, a bias electrode and a showerhead unit, and the supply of reaction gas is adjusted through the showerhead unit, and the ion energy is precisely controlled by a DC pulse generation module.
The uniformity of the plasma is improved, fine patterns and high aspect ratio patterns can be formed, and uniformity of etching and deposition is improved.
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Figure CN119562427A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a plasma generator and a method for using the same, wherein the plasma generator is intended to improve the uniformity of plasma during semiconductor manufacturing and to form fine patterns and patterns with a high aspect ratio by precisely controlling ion energy. Background Art
[0002] Plasma generators are used in the deposition and etching processes of semiconductor manufacturing equipment, liquid crystal display equipment, and solar manufacturing equipment. Therefore, it is particularly important to improve the uniformity of etching and deposition. In recent years, as the size of substrates continues to increase, the size of antennas used to generate plasma has also increased. Therefore, it is increasingly important to improve the uniformity of plasma. The source electrode (plate antenna) of the plasma generator adopts a floating design, so there is a lack of fixed boundary conditions, which leads to a decrease in the uniformity of the electric field between the center and the edge of the source electrode, thereby reducing the RF power transmitted to the edge of the source electrode. The problem with this electromagnetic field inhomogeneity is that it will induce a standing wave effect, which will affect the uniformity of the plasma at the edge of the plate antenna. In order to improve these problems, the applicant proposed a plasma generator in the registered patent gazette No. 10-1813497 (announcement date: January 2, 2018), which can improve the uniformity of plasma and can easily control the distribution of plasma.
[0003] Figure 1 (a) and (b) in the figure respectively show a front view and a plan view of a plasma generator in the related art.
[0004] Reference Figure 1 The plasma generator in the related art includes a flat plate electrode, which is composed of a source electrode unit 10 and a bias electrode unit 20 arranged in a vacuum chamber. The source electrode unit 10 is connected to the radio frequency power supply unit 40 through an impedance matching unit 30, and the bias electrode unit 20 is connected to the bias radio frequency power supply unit 50 through a bias impedance matching unit 40.
[0005] The radio frequency power supply unit 40 is connected via the first power supply contact point p1 of the source electrode unit 10 , and the first power supply contact point p1 is located at the geometric center of the source electrode unit 10 and at the position of the electromagnetic impedance center.
[0006] The bias RF power supply unit 50 is connected via the second power supply contact point p2 of the bias electrode unit 20 , and the second power supply contact point p2 is located on the bias electrode unit 20 .
[0007] The source electrode unit 10 is a circular plate-shaped electrode with multiple contact points (cp1-cp8) arranged on its edge, which are connected to a common contact point cc through respective connection lines, and the common contact point cc is connected to the impedance controller 60. The multiple contact points (cp1-cp8) are arranged in a rotationally symmetrical manner around the geometric center of the source electrode unit 110. The advantage of this plasma generator is that the uniformity of the plasma can be effectively improved by simply adjusting the impedance controller 60.
[0008] The present disclosure is devoted to developing a plasma generator for generating such plasma, and improving the uniformity of the plasma by continuously studying and improving the plasma generator for generating such plasma.
[0009] [Prior technical literature] [Patent Literature] (Patent Document 1) Registered Patent Gazette No. 10-1813497 (publication date: 2018.01.02). Summary of the invention
[0010] The present disclosure is directed to providing a plasma generator capable of improving the uniformity of plasma used in a semiconductor manufacturing process.
[0011] The present disclosure also aims to provide a plasma generator and a method of using the same, which can form fine patterns and patterns with high aspect ratios by precisely controlling ion energy.
[0012] In order to achieve the above object, a plasma generator according to one embodiment of the present disclosure includes: a vacuum chamber; a source electrode arranged in the vacuum chamber; a bias electrode, arranged in the vacuum chamber and corresponding to the source electrode, for placing a substrate; a shower head unit, arranged below the source electrode, for supplying a reaction gas to a plasma region above the substrate; a radio frequency power supply unit, for applying radio frequency power to the source electrode; and a bias power supply unit, connected to the bias electrode, for applying a bias power supply, wherein the shower head unit is used to adjust the reaction gas supplied to the central region and the edge region of the substrate.
[0013] Preferably, the shower head unit comprises: a first shower head unit, a source electrode is provided on the top of which as a protective cover, and a first gas supply unit and a first exhaust hole are also provided in the first shower head unit. The first gas supply unit is used to supply the input first gas to the edge area of the substrate, and the first gas diffused in the first gas supply unit is discharged through the first exhaust hole; and a second shower head unit, which is located below the first shower head unit, and the second shower head unit is also provided with a second gas supply unit and a second exhaust hole. The second gas supply unit is used to supply the input second gas to the central area of the substrate, and the second gas diffused in the second gas supply unit is discharged through the second exhaust hole.
[0014] More preferably, the second shower head unit is provided with a partition which divides the internal space into a central area and an edge area, the second shower head unit also includes a third gas supply unit, a third exhaust hole is formed on the third gas supply unit, for discharging the first gas input and diffused through the first exhaust hole, the second gas supply unit is used to discharge gas to the central area of the substrate, and the third gas supply unit is used to discharge gas to the edge area of the substrate.
[0015] More preferably, the source electrode includes: a first gas supply port for inputting a first gas; a second gas supply port for inputting a second gas; and a first baffle for diffusing the first gas input through the first gas supply port to the first gas supply unit.
[0016] More preferably, the first gas supply port also serves as a contact point for applying radio frequency power, and the first baffle is arranged at a central position of the source electrode.
[0017] Preferably, the first showerhead unit further comprises a second baffle for diffusing the second gas provided through the second gas supply port and supplied to the internal flow path to the second gas supply unit, and more preferably, the second baffle is disposed at a central position of the first showerhead unit.
[0018] Preferably, the bias power supply unit is a DC pulse generating module capable of generating DC bias pulses. More preferably, the DC pulse generating module includes: a pulse generator for generating AC pulses; a first rectifying unit for performing half-wave rectification on the pulses generated by the pulse generator to generate positive (+) DC pulses; and a second rectifying unit for performing half-wave rectification on the pulses generated by the pulse generator to generate negative (-) DC pulses.
[0019] Preferably, it further comprises a bias matcher and a radio frequency (RF) bias, wherein the bias matcher is used to adjust the impedance connected in parallel with the DC pulse module.
[0020] The substrate etching method using the plasma generator disclosed in the present invention for etching comprises the following steps: a first step S10, inputting gas; a second step S20, adjusting the pressure in the vacuum chamber; a third step S30, starting the RF power supply unit to apply RF power; a fourth step S40, using the DC pulse generating module to apply a negative (-) DC pulse to the bias power supply unit; and a fifth step S50, using the DC pulse generating module to apply a positive (+) DC pulse to the bias power supply unit.
[0021] According to the plasma generator disclosed herein, the showerhead unit can supply reaction gas to the plasma region above the substrate and can adjust the supply amount of reaction gas supplied to the central region and the edge region of the substrate, thereby having the effect of improving plasma uniformity.
[0022] Furthermore, the plasma generator of the present disclosure generates a DC bias pulse through a bias power supply unit of a DC pulse generating module, which enables precise control of ion energy, thereby effectively forming fine patterns and patterns with a high aspect ratio. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 (a) and (b) in the figure respectively show a front view and a plan view of a plasma generator in the related art.
[0024] Figure 2 is a schematic structural diagram of a plasma generator according to an embodiment of the present disclosure.
[0025] Figure 3 (a) and (b) are planar structural diagrams of a first shower head unit and a second shower head unit in a plasma generator according to an embodiment of the present disclosure, respectively.
[0026] Figure 4 4 is a plan view of the structure of a source electrode in a plasma generator according to an embodiment of the present disclosure.
[0027] Figure 5 (a), (b), (c), and (d) are graphs for illustrating flow rate control of gas supplied to the central region and the edge region in the plasma generator according to an embodiment of the present disclosure.
[0028] Figure 6 is a schematic structural diagram of a plasma generator according to another embodiment of the present disclosure.
[0029] Figure 7 It is a structural schematic diagram of a DC pulse generating module of a plasma generator according to another embodiment of the present disclosure.
[0030] Figure 8 The present invention is a flow chart of a process of etching a substrate using a plasma generator according to another embodiment of the present invention.
[0031] Fig. 9 and Fig.10 They are schematic diagrams of an etching process performed by a plasma generator according to another embodiment of the present disclosure.
[0032] Fig.11 is a schematic structural diagram of a plasma generator according to another embodiment of the present disclosure.
[0033] Description of Reference Numerals 100, 300, 400: plasma generator; 110: vacuum chamber; 120: source electrode; 121: first gas supply port; 122: second gas supply port; 123: first baffle; 130, 310, 410: bias electrodes; 140: radio frequency power supply unit; 141: impedance matching unit; 150: impedance controller; 160: bias RF power supply unit; 161: bias impedance matching unit; 200: shower head unit; 210: first shower head unit; 210a: first gas supply unit; 211: first exhaust hole; 220: second shower head unit; 220a: second gas supply unit; 220b: third gas supply unit; 221: second exhaust hole; 222: the third exhaust hole; 223: the second baffle. DETAILED DESCRIPTION
[0034] The description of certain structures or functions proposed in the embodiments of the present disclosure is only used to illustrate the embodiments according to the concepts of the present disclosure, and the embodiments according to the concepts of the present disclosure can be implemented in various forms. In addition, it should not be interpreted as being limited to the embodiments described in this specification, but should be understood to include all modifications, equivalents or substitutions within the scope of the ideas and technologies of the present disclosure.
[0035] On the other hand, in the present disclosure, terms such as "first" and / or "second" may be used to describe various components, but the components are not limited to the terms. The terms are only for the purpose of distinguishing one component from other components. For example, within the scope of the claims that do not depart from the concept of the present disclosure, a first component may be named a second component, and similarly, a second component may also be named a first component.
[0036] When a component is mentioned to be "connected" or "coupled" to another component, it may be directly connected or coupled to the other component, but other components may also exist in between. On the contrary, when a component is mentioned to be "directly connected to" or "directly in contact with" another component, it should be understood that there are no other components in between. Other expressions used to describe the relationship between components, namely, "between" and "just between" or "adjacent to" and "directly adjacent to" should also be interpreted in the same way.
[0037] The terms used in this specification are only used to illustrate specific embodiments, rather than to limit the intention of the present disclosure. Unless the context clearly indicates otherwise, singular expressions in the text should be understood to include plural expressions. The terms "including" or "having" used in this article are intended to indicate the presence of a certain feature, number, step, operation, component, part or combination thereof, and should not be understood to exclude the possibility of the presence or increase of one or more other features, numbers, steps, operations, components, parts or combinations thereof.
[0038] Specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.
[0039] Figure 2 is a schematic structural diagram of a plasma generator according to an embodiment of the present disclosure, Figure 3 (a) and (b) are planar structural diagrams of a first shower head unit and a second shower head unit in a plasma generator according to an embodiment of the present disclosure, respectively. Figure 4 4 is a plan view of the structure of a source electrode in a plasma generator according to an embodiment of the present disclosure.
[0040] Reference Figures 2 to 4 The plasma generator 100 of the present embodiment includes a vacuum chamber 110, a source electrode 120 disposed in the vacuum chamber 110, a bias electrode 130, and a shower head unit 200. The bias electrode 130 is disposed in the vacuum chamber 110 and corresponds to the source electrode 120, and is used to place the substrate 1. The shower head unit 200 is disposed below the source electrode 120, and is used to supply a reaction gas to the plasma region P above the substrate 1.
[0041] In the present disclosure, the shower head unit 200 is capable of adjusting the reactive gas supplied to the central area and the edge area of the substrate 1. Specifically, the shower head unit 200 includes a first shower head unit 210 and a second shower head unit 220. The first shower head unit 210 is used to input and diffuse the first gas, and the second shower head unit 220 is used to input and diffuse the second gas.
[0042] The first shower head unit 210 is provided with a source electrode 120 as a protective cover at the top. The first shower head unit is also provided with a first gas supply unit 210a for inputting and diffusing the first gas. A first exhaust hole 211 for discharging the first gas is formed below the first shower head unit.
[0043] The second shower head unit 220 is located below the first shower head unit 210. The second shower head unit is further provided with a second gas supply unit 220a for inputting and diffusing the second gas, and the second shower head unit is formed with a second exhaust hole 221 for discharging the second gas below it. Preferably, the second shower head unit 220 is provided with a third gas supply unit 220b, which is connected to the first exhaust hole 211 to input and diffuse the first gas, and at the same time, a third exhaust hole 222 for discharging the first gas is formed below the second shower head unit.
[0044] Specifically, the first shower head 210 is a cylindrical body with a predetermined depth, and a first gas supply unit 210a is formed inside the first shower head 210. The first shower head 210 is configured to have a predetermined horizontal height difference. The first shower head 210 is inserted and assembled in the second shower head unit 220. The interior of the second shower head unit 220 is separated by a partition 230 to form a second gas supply unit 220a and a third gas supply unit 220b.
[0045] A plurality of first exhaust holes 211 are formed on the first shower head unit 210 , and the first exhaust holes 211 supply the first gas from the outside of the partition plate 230 to the edge region of the substrate 1 .
[0046] A plurality of second exhaust holes 221 are formed on the second shower head unit 220, and these second exhaust holes 221 supply the second gas from the inner side of the partition 230 to the central area CZ of the substrate 1. In addition, a plurality of third exhaust holes 222 are formed, and these exhaust holes 222 directly supply the first gas from the outer side of the partition 230 to the edge area EZ of the substrate.
[0047] The first showerhead unit 210 is provided with a source electrode 120 as a protective cover at the top, and a first gas supply port 121 for inputting a first gas and a second gas supply port 122 for inputting a second gas are provided at the upper end of the protective cover. Each gas supply port 121, 122 is provided with a supply regulating valve V1, V2 for regulating the flow rate of the first gas and the flow rate of the second gas.
[0048] Preferably, the first gas supply port 121 is located at the geometric center of the source electrode 120 and serves as a power contact point connected to the RF power unit 140. The RF power unit 140 may be connected to the first gas supply port 121 through an impedance matching unit 141.
[0049] The source electrode 120 is provided with a first baffle 123 thereunder for discharging the first gas to the first gas supply unit 210a. Similarly, the first shower head unit 210 is also provided with a second baffle 223 thereunder for discharging the second gas to the second gas supply unit 220b. The source electrode 120 and the first shower head unit 210 can be connected to each gas supply port 121, 122 and the baffles 123, 223 to form an internal flow path for gas flow inside the body thereof. The first baffle 123 and the second baffle 223 are respectively disposed at the center of the source electrode 120 and the first shower head unit 210.
[0050] The bias electrode 130 is disposed in the vacuum chamber 110 and corresponds to the source electrode 120 , and is used to place the substrate 1 . A bias impedance matching unit 161 is disposed on the bias electrode 130 , and the bias impedance matching unit 161 is connected to the bias RF power supply unit 160 .
[0051] Specifically, Figure 4 As shown, the source electrode 120 is a circular plate-shaped electrode, and a plurality of contact points are arranged on its edge, and these contact points are connected to a common contact point cc through respective connecting lines, and the common contact point cc is connected to the impedance controller 150. Preferably, the plurality of contact points arranged along the edge of the source electrode 120 surround the geometric center of the source electrode 120 and are arranged in a rotationally symmetrical manner (360° / n; n is the number of contact points). In this embodiment, eight contact points are arranged along the edge of the source electrode 110 at an angle of 45°.
[0052] As described above, by providing an edge impedance adjustment device in a rotationally symmetrical manner on the source electrode 110, the edge impedance can be adjusted, and thus the plasma uniformity between the center and the edge can be adjusted, which is described in detail in the applicant's registration gazette described in the previous background technology.
[0053] The plasma generator of the present invention configured in this manner can divide the gas into a central area and an edge area, and adjust the amount of reaction gas supplied to each area, thereby improving the uniformity of etching and deposition. In addition, the gas concentration in the central area or the edge area can be adjusted in the pre-processing and post-processing stages according to specific needs.
[0054] Figure 5 (a), (b), (c), and (d) are graphs for illustrating flow rate control of gas supplied to the central region and the edge region in the plasma generator according to an embodiment of the present disclosure.
[0055] Reference Figure 5In (a) and (b), the first supply regulating valve V1 is used to regulate the first gas supplied to the edge area, and the second supply regulating valve V2 is used to regulate the second gas supplied to the central area. The gas density in the central area or the edge area can be adjusted by disconnecting the first supply regulating valve V1 and opening the second supply regulating valve V2, or opening the first supply regulating valve V1 and disconnecting the second supply regulating valve V2.
[0056] like Figure 5 As shown in (c) and (d) in FIG. 1 , by appropriately adjusting the flow rate ratio V2 / V1 of the first supply regulating valve V1 and the second supply regulating valve V2 , the etching or deposition rate can be uniformly adjusted.
[0057] In addition, the present disclosure also provides a plasma generator and a method for using the same, which can form fine patterns and patterns with a high aspect ratio by precisely controlling ion energy. Specific embodiments will be described below.
[0058] Reactive ion etching (RIE) etches the substrate by accelerating ions in a plasma environment. The force on the ions is proportional to the bias voltage on the electrostatic chuck (ESC). The self-bias voltage V applied to the electrode in RF plasma B It is expressed as (Equation 1).
[0059] (Equation 1)
[0060] In the above equation, P RF is the RF power and P is the pressure in the chamber.
[0061] To increase the self-bias voltage V B , usually requires increasing the RF power applied to the electrodes. RF To increase the self-bias voltage V B This approach consumes a lot of energy and is accompanied by high costs. In addition, when using high RF power (P RF ), a large amount of heat is generated in the chamber, which may cause damage to the substrate and become a factor in reducing the semiconductor yield.
[0062] In the case of RF self-bias, only negative bias is generated. Although its function is to accelerate the movement of positive ions to the substrate, it is the charging phenomenon of positive ions on the substrate surface or between fine patterns that becomes the factor causing the ion trajectory to bend. This is very unfavorable for the formation of fine patterns.
[0063] Figure 6is a schematic structural diagram of a plasma generator according to another embodiment of the present disclosure, Figure 7 2 is a schematic structural diagram of a DC pulse generating module of a plasma generator according to another embodiment of the present disclosure. In addition, in the following description, the same configuration is used for the same structure as the previous embodiment, and the showerhead unit disposed on the source electrode is omitted.
[0064] Reference Figure 6 According to the present embodiment, the plasma generator 300 includes a vacuum chamber 110, a source electrode 120 disposed in the vacuum chamber 110, a bias electrode 130, a radio frequency power supply unit 140, and a bias power supply unit. The bias electrode 130 is disposed in the vacuum chamber 110 and corresponds to the source electrode 120, and is used to place the substrate 1. The radio frequency power supply unit 140 is used to supply radio frequency power to the source electrode 120. The bias power supply unit is connected to the bias electrode 130 and is used to apply bias power, which is the same as the previous embodiment. Preferably, in the present disclosure, the bias power supply unit is a DC pulse generating module 310 capable of generating a DC bias pulse. This DC pulse generating module 310 generates a DC bias in the form of a pulse, wherein the DC pulse can be a positive (+) or negative (-) pulse.
[0065] Reference Figure 7 The DC pulse generating module 310 includes the following components: a pulse generator 311, a first rectifying unit 312a, and a second rectifying unit 312b. The pulse generator 311 is used to generate AC pulses; the first rectifying unit 312a is used to perform half-wave rectification on the pulses generated by the pulse generator 311, thereby generating positive (+) DC pulses; the second rectifying unit 312b is used to perform half-wave rectification on the pulses generated by the pulse generator 111, thereby generating negative (-) DC pulses. A radio frequency filter 313 may be added to the output ends of the first rectifying unit 312a and the second rectifying unit 312b.
[0066] Figure 8 is a flow chart of a substrate etching process performed by a plasma generator according to another embodiment of the present disclosure. Fig. 9 and Fig.10 They are schematic diagrams of an etching process performed by a plasma generator according to another embodiment of the present disclosure.
[0067] Reference Figure 8The substrate etching method includes the following steps: a first step S10, inputting gas; a second step S20, adjusting the pressure in the vacuum chamber; a third step S30, applying RF power; a fourth step S40, using a DC pulse generating module to apply a negative (-) DC pulse to a bias power unit; and a fifth step S50, using a DC pulse generating module to apply a positive (+) DC pulse to the bias power unit; and a sixth step S60, performing substrate etching.
[0068] like Fig. 9 As shown in (a) of FIG. 1 , in the fourth step S40 , a negative (-) DC pulse (several ms) is applied to the bias power supply unit to accelerate the movement of the target ions (+) toward the substrate 1 . Fig. 9 In part (b), the upper side shows the DC pulse generated by the DC pulse generating module, while the lower side shows the DC pulse signal applied to the bias power supply unit. It is worth noting that the pulse waveform applied to the bias power supply unit presents a very short pulse waveform due to the saturation of the plasma. In addition, Fig. 9 As shown in (c) in FIG. 1 , when positive (+) ions accelerated to pattern 2 on substrate 1 accumulate in pattern 2, the trajectories of the ions are distorted, thereby forming a daisy shape in the pattern.
[0069] Next, in the fifth step S50, a positive (+) DC pulse is applied to the bias power supply to discharge positive ions (such as Fig.10 (a)). Fig.10 In part (b), the upper and lower sides respectively show the DC pulses generated by the DC pulse generation module and the DC pulses applied to the bias power supply unit. This process can obtain patterns with a high aspect ratio (h / d) (such as Fig.10 (as shown in (c)).
[0070] Fig.11 2 is a schematic structural diagram of a plasma generator according to another embodiment of the present disclosure. In the following description, repeated descriptions of the same configuration parts as in the previous embodiment will be omitted.
[0071] Reference Fig.11 In the plasma generator 400 of this embodiment, a DC pulse generating module 410 for generating DC pulses is configured as a bias power supply unit connected to an electrostatic chuck for applying a bias power supply. This is the same as the previous embodiment. It is worth noting that a bias matcher 420 and a radio frequency (RF) bias 430 may also be added. The bias matcher 420 is used to adjust the impedance connected in parallel with the DC pulse generating module 410.
[0072] The present disclosure is not limited to the aforementioned embodiments and drawings, and it is obvious to those skilled in the art that various substitutions, deformations, and changes may be made to the present disclosure without departing from the technical concept of the present disclosure.
Claims
1. A plasma generator, characterized in that: include: Vacuum chamber; a source electrode disposed in the vacuum chamber; A bias electrode, disposed in the vacuum chamber and corresponding to the source electrode, for placing a substrate; a showerhead unit, disposed below the source electrode and configured to supply a reactive gas to a plasma region above the substrate; A radio frequency power supply unit, used for applying radio frequency power to the source electrode; as well as, A bias power supply unit, connected to the bias electrode, for applying a bias power supply; The shower head unit is used to adjust the reaction gas supplied to the central area and the edge area of the substrate.
2. The plasma generator according to claim 1, characterized in that: The shower head unit comprises: A first shower head unit, with a source electrode disposed on the top as a protective cover, and a first gas supply unit and a first exhaust hole are also disposed in the first shower head unit, wherein the first gas supply unit is used to supply the input first gas to the edge area of the substrate, and the first gas diffused in the first gas supply unit is discharged through the first exhaust hole; The second shower head unit is located below the first shower head unit. The second shower head unit is also provided with a second gas supply unit and a second exhaust hole. The second gas supply unit is used to supply the input second gas to the central area of the substrate. The second gas diffused in the second gas supply unit is discharged through the second exhaust hole.
3. The plasma generator according to claim 2, characterized in that: The second shower head unit is provided with a partition that divides the internal space into a central area and an edge area. The second shower head unit also includes a third gas supply unit. The third gas supply unit is formed with a third exhaust hole for discharging the first gas input and diffused through the first exhaust hole. The second gas supply unit is used to discharge gas to the central area of the substrate, and the third gas supply unit is used to discharge gas to the edge area of the substrate.
4. The plasma generator according to claim 2, characterized in that: The source electrode comprises: A first gas supply port, used for inputting a first gas; A second gas supply port is used to input a second gas; and The first baffle is used to diffuse the first gas input through the first gas supply port to the first gas supply unit.
5. The plasma generator according to claim 4, characterized in that The first gas supply port also serves as a contact point for applying radio frequency power.
6. The plasma generator according to claim 5, characterized in that The first baffle is disposed at the center of the source electrode.
7. The plasma generator according to claim 4, characterized in that The first shower head unit also includes: A second baffle for diffusing the second gas provided through the second gas supply port and supplied to the internal flow path to the second gas supply unit.
8. The plasma generator according to claim 7, characterized in that The second baffle is disposed at a center position of the first shower head unit.
9. The plasma generator according to claim 1, characterized in that: The bias power supply unit is a DC pulse generating module, which can generate a DC bias pulse.
10. The plasma generator according to claim 9, characterized in that The DC pulse generating module comprises: A pulse generator for generating AC pulses; a first rectifying unit, configured to perform half-wave rectification on the pulses generated by the pulse generator to generate positive DC pulses; and The second rectifying unit is used for performing half-wave rectification on the pulses generated by the pulse generator to generate negative DC pulses.
11. The plasma generator according to claim 9, characterized in that It also includes a bias matcher and a radio frequency (RF) bias, wherein the bias matcher is used to adjust the impedance connected in parallel with the DC pulse module.
12. A substrate etching method, characterized in that: Etching using the plasma generator of claim 9 comprises the following steps: The first step (S10) is to input gas; The second step (S20) is to adjust the pressure in the vacuum chamber; The third step (S30) is to start the radio frequency power supply unit to apply radio frequency power; The fourth step (S40) is to apply a negative DC pulse to the bias power supply unit by using the DC pulse generating module; and The fifth step (S50) is to use the DC pulse generating module to apply a positive DC pulse to the bias power supply unit.