Plasma equipment

Abstract

This disclosure provides a plasma device, belonging to the field of semiconductor device technology. The plasma device includes: a dielectric cylinder; a first cover plate, covering the upper part of the dielectric cylinder and forming a plasma generation space together with the dielectric cylinder; the first cover plate is provided with a first acceleration module; the first acceleration module includes: a first electrode, a first insulating layer, and a first electrode feeder, wherein the first insulating layer covers the first electrode, and the first electrode feeder is used to feed energy into the first electrode to form a first electric field, the first electric field being used to adjust the vertical velocity of ions in the plasma flowing from the plasma space to the workpiece processing space along the axial direction of the plasma device, thereby adjusting the vertical velocity of free radicals in the plasma; a coil, disposed outside the dielectric cylinder; a housing, located below the dielectric cylinder; and a second cover plate, connected to the lower part of the dielectric cylinder and covering the upper part of the housing, forming a workpiece processing space together with the housing.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor equipment technology, and more particularly to a plasma device. Background Technology

[0002] Plasma equipment based on remote plasma technology is a crucial process tool in semiconductor chip manufacturing. Remote plasma technology generates plasma at a distance from the wafer. As the plasma passes through a grid, the grid eliminates most of the ions in the plasma, reducing ion bombardment of the wafer. The neutralized free radicals in the plasma continue to move and reach the wafer surface to undergo chemical reactions, completing the wafer surface treatment. Currently, improving the efficiency of wafer surface treatment remains a key research topic. Summary of the Invention

[0003] This disclosure provides a plasma device.

[0004] As one aspect of this disclosure, an embodiment provides a plasma device, comprising: a dielectric cylinder; a first cover plate, covering the upper part of the dielectric cylinder and forming a plasma generation space together with the dielectric cylinder; the first cover plate is provided with a first acceleration module; wherein the first acceleration module includes: a first electrode, a first insulating layer, and a first electrode feeder, wherein the first insulating layer covers the first electrode, and the first electrode feeder is used to feed energy into the first electrode to form a first electric field, the first electric field being used to adjust the vertical velocity of ions in the plasma flowing from the plasma space to the workpiece processing space along the axial direction of the plasma device, thereby adjusting the vertical velocity of free radicals in the plasma; a coil, disposed on the outside of the dielectric cylinder, for exciting process gas in the plasma generation space into plasma; a housing, located below the dielectric cylinder; a second cover plate, connected to the lower part of the dielectric cylinder and covering the upper part of the housing, forming a workpiece processing space together with the housing; and a grid, located between the plasma generation space and the workpiece processing space.

[0005] In some embodiments, the first acceleration module is laid on the upper or lower surface of the first cover plate.

[0006] In some embodiments, the orthographic projection of the first acceleration module onto the upper surface of the first cover plate covers the orthographic projection of the workpiece onto the upper surface of the first cover plate.

[0007] In some embodiments, the orthographic projection of the first acceleration module onto the upper surface of the first cover plate covers the upper surface of the first cover plate.

[0008] In some embodiments, the first electrode feeder is located on the side of the first acceleration module.

[0009] In some embodiments, the first acceleration module has multiple components.

[0010] In some embodiments, at least two of the first acceleration modules are arranged in a fan shape, and at least two of the first acceleration modules are arranged circumferentially along the first cover plate.

[0011] In some embodiments, at least two of the first acceleration modules are arranged in a ring shape, and a plurality of the first acceleration modules arranged in a ring shape are concentrically arranged.

[0012] In some embodiments, at least one second acceleration module is provided in the second cover plate; wherein the second acceleration module includes: a second electrode, a second insulating layer, and a second electrode feeder, wherein the second insulating layer covers the second electrode, and the second electrode feeder is used to feed energy into the second electrode to form a second electric field, the second electric field being used to adjust the horizontal velocity of ions in the plasma flowing from the plasma space to the workpiece processing space, thereby adjusting the horizontal velocity of free radicals in the plasma; the second acceleration module is located above the grid.

[0013] In some embodiments, the second acceleration module has multiple modules, and the multiple second acceleration modules are spaced apart and evenly distributed along a preset circumference.

[0014] In some embodiments, the diameter of the preset circumference is larger than the diameter of the space in the workpiece processing space.

[0015] In some embodiments, the plasma device further includes: a first voltage control module electrically connected to the first electrode feeder of the first acceleration module to control the intensity of the first electric field formed by the first electrode of the first acceleration module.

[0016] In some embodiments, the plasma device further includes: a second voltage control module electrically connected to the second electrode feeders of the plurality of second acceleration modules, respectively, to control the intensity of the second electric field formed by the second electrodes of the plurality of second acceleration modules.

[0017] This embodiment of the invention applies a voltage to the first electrode of the first acceleration module to form a first electric field. The first electric field enables ions in the plasma to have a downward acceleration, thereby increasing the downward vertical velocity of the ions. By utilizing the impact of ions on free radicals, the downward vertical velocity of the free radicals is increased, allowing the free radicals to reach the workpiece surface more quickly to carry out chemical reactions, thereby effectively shortening the process time and improving the processing efficiency of the workpiece surface.

[0018] The above overview is for illustrative purposes only and is not intended to be limiting in any way. Further aspects, embodiments, and features of this disclosure will become readily apparent from the accompanying drawings and the following detailed description, in addition to the illustrative aspects, embodiments, and features described above. Attached Figure Description

[0019] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this disclosure and should not be construed as limiting the scope of this disclosure.

[0020] Figure 1 A schematic diagram of the structure of a plasma device according to an embodiment of the present disclosure is shown; Figure 2 A schematic diagram of the structure of the first cover plate according to an embodiment of the present disclosure is shown; Figure 3 A schematic diagram of the structure of the second cover plate according to an embodiment of the present disclosure is shown. Figure 1 ; Figure 4 A schematic diagram of the structure of a second acceleration module according to an embodiment of the present disclosure is shown; Figure 5 A schematic diagram of the structure of the second cover plate according to an embodiment of the present disclosure is shown. Figure 2 .

[0021] Explanation of reference numerals in the attached drawings: 10-First cover plate; 11-Process gas channel; 12-First acceleration module; 121-First electrode; 122-First insulating layer; 123-First electrode feeder; 20-Dielectric cylinder; 21-Plasma generation space; 30-Coil; 40-Second cover plate; 41-Second acceleration module; 411-Second electrode; 412-Second insulating layer; 413-Second electrode feeder; 50-Box; 51-Workpiece processing space; 61-First sealing ring; 62-Second sealing ring; 63-Third sealing ring; 70-Grid; 80-Workpiece. Detailed Implementation

[0022] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this disclosure. Therefore, the drawings and description are to be considered exemplary in nature and not restrictive.

[0023] In related technologies, the path of free radicals in plasma from the plasma generation space vertically downward to the wafer surface in the workpiece processing space is relatively long, resulting in a long process time and low wafer surface processing efficiency.

[0024] This embodiment provides a plasma device. By configuring a first acceleration module in a first cover plate, a voltage is applied to the first electrode of the first acceleration module to form a first electric field. The first electric field enables ions in the plasma to have a downward acceleration, thereby increasing the downward vertical velocity of the ions. By utilizing the impact of ions on free radicals, the downward vertical velocity of the free radicals is increased, allowing the free radicals to reach the workpiece surface more quickly to carry out chemical reactions, thereby effectively shortening the process time and improving the processing efficiency of the workpiece surface.

[0025] The structure, function, and implementation process of the plasma device in this embodiment will be illustrated below with reference to the accompanying drawings.

[0026] Please refer to Figures 1 to 2 The plasma device provided in this embodiment includes: a dielectric cylinder 20; a first cover plate 10, which covers the upper part of the dielectric cylinder 20 and together with the dielectric cylinder 20 forms a plasma generation space 21; the first cover plate 10 is provided with a first acceleration module 12; a coil 30, which is disposed on the outside of the dielectric cylinder 20 and is used to excite the process gas in the plasma generation space 21 into plasma; a housing 50, which is located below the dielectric cylinder 20; a second cover plate 40, which is connected to the lower part of the dielectric cylinder 20 and covers the upper part of the housing 50, together with the housing 50 forming a workpiece processing space 51; and a grid 70, which is located on the upper part of the workpiece processing space 51. The workpiece 80 may include a wafer.

[0027] The first acceleration module 12 includes a first electrode 121, a first insulating layer 122, and a first electrode feeder 123. The first insulating layer 122 covers the first electrode 121, and the first electrode feeder 123 is used to feed energy into the first electrode 121 to form a first electric field. The first electric field is used to adjust the vertical velocity of ions in the plasma flowing from the plasma space to the workpiece processing space 51 along the axial direction of the plasma device, thereby adjusting the vertical velocity of free radicals in the plasma.

[0028] The dielectric tube 20 is typically cylindrical. The axis of the dielectric tube 20 is parallel to the axis of the plasma device. The dielectric tube 20 can be made of quartz; therefore, it can also be called a quartz tube.

[0029] The upper end of the dielectric cylinder 20 is sealed and covered by a first cover plate 10, together forming a relatively enclosed plasma generation space 21. A first sealing ring 61 is abutted between the first cover plate 10 and the dielectric cylinder 20. Exemplarily, the first cover plate 10 includes a first plate body, the lower surface of which is provided with a downwardly extending extension ring. The extension ring is located near the outer edge of the first plate body, and its inner sidewall gradually slopes outwards in a downward direction. When the first plate body covers the upper end of the dielectric cylinder 20, the extension ring is located on the outer side of the dielectric cylinder 20, and the first sealing ring 61 abuts between the inner sidewall of the extension ring and the outer sidewall of the dielectric cylinder 20.

[0030] The first cover plate 10 is provided with a first acceleration module 12, which is specifically disposed on the first plate body. The first acceleration module 12 may be disposed on the upper surface of the first plate body, or on the lower surface of the first plate body, or embedded in the first plate body.

[0031] The first acceleration module 12 includes a first electrode 121, a first insulating layer 122, and a first electrode feeder 123. The first electrode 121 can be a metal component, such as one made of conductive materials like aluminum or stainless steel. The first electrode 121 can be flat. The first electrode 121 can be arranged parallel to the first plate. The first insulating layer 122 can be made of insulating material and tightly covers the outer periphery of the first electrode 121, completely isolating the first electrode 121 from the surrounding first cover plate 10. The first electrode feeder 123 can be a metal conductor connected to the first electrode 121. The first electrode feeder 123 is connected to an external power source to feed electrical energy into the first electrode 121.

[0032] When a certain voltage (such as radio frequency voltage or DC voltage) is applied to the first electrode 121 through the first electrode feeder 123, a first electric field is formed on the side of the first electrode 121 facing the plasma generation space 21. The first electric field force accelerates the ions in the plasma, significantly increasing the vertical velocity component of the ions (i.e., the velocity perpendicular to the wafer surface, simply referred to as vertical velocity), thereby increasing the vertical velocity of the free radicals colliding with the ions.

[0033] The first cover plate 10 is provided with a process gas channel 11, which is used to transport external process gas to the plasma generation space 21. The portion of the first acceleration module 12 corresponding to the process gas channel 11 is provided with clearance holes.

[0034] A coil 30 is arranged around the outside of the dielectric cylinder 20. This coil 30 is connected to a radio frequency power supply. When process gas is introduced into the plasma generation space 21, radio frequency current is passed through the coil 30, generating an alternating electromagnetic field, thereby exciting the process gas to form a plasma containing a large number of ions, free radicals, and other particles. The specific composition of the process gas can be set according to actual needs; this embodiment does not impose any limitations.

[0035] The upper port of the housing 50 is connected and sealed to the lower part of the dielectric cylinder 20 via a second cover plate 40. The second cover plate 40 and the housing 50 together form a workpiece processing space 51. A support structure for carrying the wafer is disposed within the workpiece processing space 51. For example, the lower part of the dielectric cylinder 20 is inserted into the central hole of the second cover plate 40, and a second sealing ring 62 is abutting between the outer wall of the dielectric cylinder 20 and the wall of the central hole of the second cover plate 40. The second cover plate 40 covers the upper end of the housing 50, and a third sealing ring 63 is abutting between the lower surface of the second cover plate 40 and the upper surface of the housing 50.

[0036] Below the second cover plate 40, a grid 70 is provided. The grid 70 is densely covered with through holes to equalize the plasma flow and block most of the ions.

[0037] The plasma device provided in this embodiment, by configuring a first acceleration module 12 in the first cover plate 10, applies a voltage to the first electrode 121 of the first acceleration module 12 to form a first electric field. The first electric field enables ions in the plasma to have a downward acceleration, thereby increasing the downward vertical velocity of the ions. Utilizing the impact of ions on free radicals, the downward vertical velocity of the free radicals is increased, allowing the free radicals to reach the workpiece surface more quickly for chemical reactions, increasing the reaction rate, and thus effectively shortening the process time and improving the processing efficiency of the workpiece surface. In addition, the downward vertical velocity of the ions can be controlled by controlling the magnitude of the downward acceleration. By utilizing the impact of ions on free radicals, the vertical velocity of the free radicals can be controlled and adjusted, flexibly adjusting the concentration of free radicals on the wafer surface.

[0038] In some embodiments, the second acceleration module 41 is laid on the upper or lower surface of the first cover plate 10. In some examples, the first acceleration module 12 is mounted as a single unit on the upper surface of the first cover plate 10 (first plate body). Specifically, the first electrode 121 (typically a metal plate or metal mesh) is mechanically fixed to the upper surface of the first cover plate 10 via a first insulating layer 122 around its periphery. The first insulating layer 122 can be a structure made of ceramic, quartz, or other insulating materials. The first electrode feed member 123 extends from the side or top of the first acceleration module 12.

[0039] In this example, the first acceleration module 12 is located outside the plasma generation space 21, physically isolated from the process gas and plasma. This protects the first acceleration module 12 from direct plasma bombardment and chemical corrosion by reactive gases, significantly improving its reliability and lifespan. Furthermore, the first cover plate 10 does not need to be opened during maintenance or replacement of the first acceleration module 12, making maintenance convenient.

[0040] In some examples, the first acceleration module 12 is mounted on the lower surface of the first cover plate 10 (first plate), i.e., on the side facing the plasma generation space 21. In this case, the first insulating layer 122 needs to directly face the plasma, and its material and thickness need to be able to withstand plasma erosion and high thermal load.

[0041] In this example, the first acceleration module 12 is located inside the plasma generation space 21 and is directly immersed in the plasma environment. The first electrode 121 is closer to the plasma, and the electric field it forms is stronger and more direct, which may result in higher acceleration efficiency for ions and a faster response.

[0042] In other examples, the first acceleration module 12 can also be embedded inside the first cover plate 10. That is, the first electrode 121 is completely covered and sealed inside the cover plate from both the top and bottom by a first insulating material (such as quartz or alumina ceramic). This combines the advantages of protection with direct electric field.

[0043] In some embodiments, the orthographic projection of the first acceleration module 12 onto the upper surface of the first cover plate 10 covers the orthographic projection of the workpiece 80 onto the upper surface of the first cover plate 10. The orthographic projection of the first acceleration module 12 onto the upper surface of the first cover plate 10 is concentric with the orthographic projection of the workpiece 80 onto the upper surface of the first cover plate 10. The orthographic projection of the first acceleration module 12 onto the upper surface of the first cover plate 10 is greater than or equal to the orthographic projection of the workpiece 80 onto the upper surface of the first cover plate 10.

[0044] When the orthographic projection of the first acceleration module 12 onto the upper surface of the first cover plate 10 is equal to the orthographic projection of the workpiece 80 onto the upper surface of the first cover plate 10, the first electrode 121 is precisely aligned with the workpiece 80 below in the horizontal plane. This ensures that the accelerating electric field generated by the first acceleration module 12 is concentrated on the area directly above the workpiece 80, avoiding unnecessary dissipation around the edge of the workpiece 80. Thus, under the same input power, efficient acceleration of ions and free radicals in the target area can be achieved.

[0045] For example, the orthographic projection of the first acceleration module 12 onto the upper surface of the first cover plate 10 covers the upper surface of the first cover plate 10. In this way, the first electrode 121 extends to almost the entire usable area of ​​the plasma generation space 21 in the horizontal direction, so that the ions generated on the entire cross-section of the plasma generation space 21 can obtain downward acceleration, which can provide downward acceleration for more free radicals, thereby increasing the vertical velocity of more free radicals.

[0046] When the orthographic projection of the first acceleration module 12 onto the upper surface of the first cover plate 10 is greater than the orthographic projection of the workpiece 80 onto the upper surface of the first cover plate 10, it ensures that the accelerating electric field generated by the first acceleration module 12 acts on more ions and can also accelerate more free radicals.

[0047] In some embodiments, the first electrode feeder 123 is located on the side of the first acceleration module 12. This avoids placing high-voltage lines directly above the plasma device, keeping the space above the first cover plate 10 flat and facilitating the installation of other components or maintenance operations. Moreover, for the circular first electrode 121, feeding from the side, compared to feeding from the top center, reduces potential interference with the electric field distribution in the central region of the first electrode 121, contributing to the formation of a first electric field with better axisymmetry, which is beneficial for the rotational symmetry of workpiece processing.

[0048] In some embodiments, there are multiple first acceleration modules 12. Each first acceleration module is an independently controllable unit. Multiple first acceleration modules 12 can be spliced ​​together to cover the target area (such as the entire surface of the first cover plate 10 or the wafer projection area), with small insulating gaps between them to prevent arc discharge.

[0049] This configuration, by controlling the intensity of the electric field of the first acceleration module 12 separately, helps ensure the uniformity of the workpiece surface treatment. For example, by applying different voltages to the two first acceleration modules 12, local acceleration electric fields with independently adjustable intensity can be formed above the two horizontal regions corresponding to the plasma generation space 21, which facilitates the fine control of the vertical velocity of free radicals.

[0050] In some examples, at least two first acceleration modules 12 are arranged in a fan shape, and at least two first acceleration modules 12 are arranged circumferentially along the first cover plate 10. When the process non-uniformity is angle-dependent, the voltage of the first acceleration module 12 at the corresponding position can be independently adjusted. For example, the electric field of the first acceleration module 12 corresponding to the region with high free radical concentration can be reduced, thereby reducing the ion driving effect in that region and balancing the free radical concentration.

[0051] For example, multiple identical sector structures can be seamlessly joined to form a complete circular or annular area. The apex angle (central angle) of a sector can be determined based on the number of partitions. For example, with 6 partitions, each sector has a apex angle of 60 degrees, and with 4 partitions, each sector has a apex angle of 90 degrees.

[0052] For example, each complete sector region may have multiple first acceleration modules 12. In this case, the multiple first acceleration modules 12 in each sector region are arranged radially along the first cover plate 10. That is, the multiple first acceleration modules 12 are radially distributed with the central axis of the plasma device as the center.

[0053] In some examples, at least two of the first acceleration modules 12 are arranged in a ring shape, and multiple ring-shaped first acceleration modules 12 are arranged concentrically from the center to the periphery.

[0054] Each annular first acceleration module 12 covers a specific radial region. Taking a configuration with 3 rings as an example, the inner ring module, middle ring module, and outer ring module are arranged from the inside out. The inner ring module corresponds to the central region of the workpiece 80, the middle ring module corresponds to the middle region of the workpiece 80, and the outer ring module corresponds to the edge region of the workpiece 80.

[0055] The most common non-uniformity mode in plasma processing is radial non-uniformity from the center to the edge (such as edge effects causing fast or slow edge velocities). By independently controlling the electric field strength of different ring modules, the flux of ions and free radicals flowing to different radii of the workpiece can be directly adjusted. For example, if the edge etching is too fast, the voltage of the outer ring module can be reduced to weaken the acceleration effect of the plasma on the edge region.

[0056] The width of the ring module does not have to be uniform. For example, a narrower ring can be used in radial locations where the process changes drastically (usually near the edge) to achieve finer control.

[0057] In some application scenarios, the first acceleration module 12 can also adopt a combination of annular and sector modules. For example, an annular module can be used in the area closer to the central axis of the plasma device; multiple sector modules can be arranged circumferentially in the area closer to the edge of the workpiece 80. The sector modules here do not have to be complete sector shapes; they can be set according to actual needs.

[0058] In some embodiments, to enhance the flexibility and intelligence of process control, the plasma device further includes a first voltage control module electrically connected to the first electrode feeder 123 to control the intensity of the first electric field formed by the first electrode 121.

[0059] When there are multiple first acceleration modules 12, the first voltage module is electrically connected to the first electrode feed member 123 of the multiple first acceleration modules 12 respectively, so as to control the intensity of the first electric field formed by the first electrode 121 of the multiple first acceleration modules 12 respectively.

[0060] The first voltage control module is electrically connected to the first electrode feed 123 of each first acceleration module 12 via independent lines. In this way, the first voltage control module can independently control the voltage signal (including voltage amplitude, frequency, phase or on / off) applied to the first electrode 121 of each first acceleration module 12, thereby separately and precisely regulating the intensity of the first electric field generated by each first acceleration module 12, and realizing the adjustment of the free radical concentration at a set position on the wafer surface.

[0061] In some application scenarios, the housing 50 can be equipped with a detection structure for detecting the concentration of free radicals or a detection structure for detecting the surface treatment effect of wafers. The detection results of the detection structure are used to provide a reliable reference for the first voltage control module to control the first acceleration module 12.

[0062] In this embodiment, the strength of the first electric field in a certain area can be flexibly and specifically enhanced or weakened. For example, if real-time monitoring reveals that the etching rate on the right side of the wafer is too slow, the voltage of the first acceleration module 12 located on the right side can be increased separately to increase the vertical velocity of ions in that area, thereby allowing more free radicals to reach the right side of the wafer surface more quickly, achieving dynamic compensation.

[0063] In other embodiments, each first acceleration module 12 may be configured with an independent first voltage control module.

[0064] Please refer to Figures 3 to 5 In some embodiments, at least one second acceleration module 41 is provided in the second cover plate 40; wherein the second acceleration module 41 includes: a second electrode 411, a second insulating layer 412 and a second electrode feeder 413, wherein the second insulating layer 412 covers the second electrode 411, and the second electrode feeder 413 is used to feed energy into the second electrode 411 to form a second electric field, the second electric field is used to adjust the horizontal velocity of ions in the plasma from the plasma space to the workpiece processing space 51, thereby adjusting the horizontal velocity of free radicals in the plasma; the second acceleration module 41 is located above the grid 70.

[0065] At least one second acceleration module 41 is provided in the second cover plate 40; wherein the second acceleration module 41 includes: a second electrode 411, a second insulating layer 412 and a second electrode feeder 413, wherein the second insulating layer 412 covers the second electrode 411, and the second electrode feeder 413 is used to feed energy into the second electrode 411 to form a second electric field, and the second electric field is used to adjust the horizontal velocity of ions in the plasma from the plasma space to the workpiece processing space 51, thereby adjusting the horizontal velocity of free radicals in the plasma.

[0066] At least one second acceleration module 41 is embedded within the second cover plate 40. The second acceleration module 41 includes a second electrode 411, a second insulating layer 412, and a second electrode feed member 413. The second electrode 411 can be a metal component, such as one made of conductive materials like aluminum or stainless steel. The second insulating layer 412 can be made of insulating material and tightly covers the outer periphery of the second electrode 411, completely isolating the second electrode 411 from the surrounding second cover plate 40. The second electrode feed member 413 can be a metal conductor connected to the second electrode 411. This second electrode feed member 413 is connected to an external power source to feed energy into the second electrode 411.

[0067] When a certain voltage (such as radio frequency voltage or DC voltage) is applied to the second electrode 411 through the second electrode feeder 413, a second electric field is formed on the side of the second electrode 411 facing the central axis of the plasma device. This second electric field is located in the path of the plasma flowing from the plasma generation space to the workpiece processing space 51. This second electric field mainly acts on the ions in the plasma that diffuses downward from the upper plasma generation space 21 and is about to enter the workpiece processing space 51. The second electric field force accelerates the ions, significantly increasing the horizontal velocity component of the ions (i.e., the velocity parallel to the wafer surface, simply referred to as horizontal velocity), thereby increasing the horizontal velocity of the free radicals colliding with the ions.

[0068] Below the second cover plate 40 and near the second acceleration module 41, a grid 70 is provided. The grid 70 is densely covered with through holes for equalizing plasma flow and blocking most ions.

[0069] In this embodiment, a second acceleration module 41 is provided in the second cover plate 40. The second electric field generated by the second acceleration module 41 horizontally accelerates the ions, giving them a greater horizontal velocity. During their downward movement, these accelerated ions collide with electrically neutral free radicals. Through momentum transfer, the free radicals are propelled by the ions, and their horizontal velocity is correspondingly increased. By adjusting the voltage (such as voltage amplitude, frequency, or waveform) applied to the second electrode 411 of the second acceleration module 41, the degree of ion acceleration can be precisely controlled, thereby flexibly adjusting the radial concentration distribution of free radicals on the wafer surface. Ultimately, the free radical flux (or concentration) received at various points on the wafer surface becomes more uniform, significantly improving the consistency of the wafer surface treatment effect and enhancing the uniformity of the wafer surface treatment.

[0070] In some embodiments, there are multiple second acceleration modules 41, and the multiple second acceleration modules 41 are spaced apart and evenly distributed along a preset circumference. For example, there may be 4, 6, 8, 10 or more second acceleration modules 41, and the specific number of second acceleration modules 41 can be set according to actual needs.

[0071] In this embodiment, by setting multiple uniformly distributed second acceleration modules 41, a uniform or independently adjustable second electric field ring can be formed in the circumferential direction of the wafer, ensuring that ions coming down from the plasma generation space 21 can be accelerated by the corresponding second acceleration module 41 regardless of their radial orientation, thereby effectively improving the uniformity of the wafer surface treatment.

[0072] In some embodiments, the diameter of the preset circumference is larger than the diameter of the space in the workpiece processing space 51. Thus, the annular region where the plurality of second acceleration modules 41 are distributed covers and extends beyond the edge of the wafer surface.

[0073] In this embodiment, the second acceleration module 41 is set on a circumference larger than the actual area of ​​the wafer. The second electric field generated by the second acceleration module 41 can accelerate the ions that exceed the edge of the wafer (that is, the ions corresponding to the periphery of the wafer). After these ions collide with free radicals, they can more effectively push the free radicals located directly above the wafer and corresponding to the periphery of the wafer further into the space above the wafer, thereby accurately compensating for the free radical concentration in the wafer edge region and significantly improving the uniformity of the wafer edge.

[0074] In some embodiments, to improve the flexibility and intelligence of process control, the plasma device further includes a second voltage control module, which is electrically connected to the second electrode feeders 413 of the plurality of second acceleration modules 41 respectively, so as to control the intensity of the second electric field formed by the second electrodes 411 of the plurality of second acceleration modules 41 respectively.

[0075] The second voltage control module is electrically connected to the second electrode feed 413 of each second acceleration module 41 via independent lines. In this way, the second voltage control module can independently control the voltage signal (including voltage amplitude, frequency, phase or on / off) applied to the second electrode 411 of each second acceleration module 41, thereby separately and precisely regulating the intensity of the second electric field generated by each second acceleration module 41, and realizing the adjustment of free radical concentration at a set position on the wafer surface.

[0076] In some application scenarios, the housing 50 can be equipped with a detection structure for detecting the concentration of free radicals or a detection structure for detecting the surface treatment effect of wafers. The detection results of the detection structure are used to provide a reliable reference for the second voltage control module to control the second acceleration module 41.

[0077] In this embodiment, the strength of the second electric field in a certain area can be flexibly and specifically enhanced or weakened. For example, if real-time monitoring detects that the etching rate on the right side of the wafer is too slow, the voltage of the second acceleration module 41 located on the right side can be increased separately to increase the horizontal velocity of ions in that area, thereby pushing more free radicals to the right side of the wafer surface and achieving dynamic compensation.

[0078] In other embodiments, each second acceleration module 41 may be configured with an independent second voltage control module.

[0079] In some embodiments, the plurality of second acceleration modules 41 are symmetrically distributed about the longitudinal center plane of the plasma device. The plurality of second acceleration modules 41 are symmetrically distributed about the transverse center plane of the plasma device.

[0080] In this configuration, the longitudinal, transverse, and vertical directions are all perpendicular to each other, with the vertical direction being the straight line. For example, see the diagram. Figure 4 As shown, Figure 4 The left and right directions are horizontal. Figure 4 The vertical direction is the vertical direction. Figure 4 The direction perpendicular to the paper is called the vertical direction.

[0081] In this embodiment, the second acceleration module 41 is symmetrically distributed to avoid the problem of etching or deposition on one side of the wafer being faster than the other.

[0082] In some embodiments, the second electrode 411 is plate-shaped and parallel to the axial direction of the plasma device. For example, the second electrode 411 is rectangular plate-shaped.

[0083] The shape and orientation of the second electrode 411 determine the distribution of the second electric field it generates. By using a plate-shaped second electrode 411 parallel to the axial direction, when a voltage is applied, the generated second electric field lines are mainly concentrated and strong on both sides of the plate surface of the second electrode 411 (i.e., in the horizontal direction). This configuration of the second electric field can more effectively apply a horizontal force to vertically falling ions, making the control of the horizontal velocity of ions more direct and significant, and consequently, the control of the horizontal velocity of free radicals also more direct and significant.

[0084] In some embodiments, the second electrode feeder 413 is connected to the upper part of the second electrode 411; the second electrode feeder 413 is electrically connected to the voltage control module via a wire; the second cover plate 40 is provided with a cable management groove, the groove opening of which is located on the upper surface of the second cover plate 40, and the wire is housed in the cable management groove.

[0085] The bottom end of the second electrode feed member 413 (e.g., a metal rod) is fixed to the upper part (e.g., the top center) of the second electrode 411, such as by welding or threading. The top end of the second electrode feed member 413 passes through the second insulating layer 412.

[0086] The second electrode feeder 413 is electrically connected to the voltage control module via wires. To simplify the wiring of the plasma equipment and prevent wire interference or accidental short circuits, recessed cable management grooves are machined on the upper surface of the second cover plate 40. These cable management grooves start from the exit position of each second electrode feeder 413, converge, and lead to an electrical connection area at the edge of the second cover plate 40. All connecting wires are housed in the corresponding cable management grooves and finally led out to the external voltage control module through the electrical connection area.

[0087] Optionally, an openable and closable protective cover can be installed at the opening of the cable tray to protect the wires inside. The protective cover can be opened and closed by sliding or rotating. Alternatively, the protective cover can be detachably connected to the second cover plate 40.

[0088] In some embodiments, the second cover plate 40 is provided with a mounting hole, the opening of which is located on the upper surface of the second cover plate 40, and the second acceleration module 41 is detachably mounted in the mounting hole.

[0089] The mounting hole is a blind hole. The shape and size of the mounting hole are adapted to the external contour of the second acceleration module 41. For example, if the second acceleration module 41 is rectangular, the mounting hole is a flat rectangular blind hole. The second acceleration module 41, as an independent prefabricated component, can be integrally and detachably inserted and fixed in the mounting hole. The detachable connection method can be a fastening connection, a damping connection, a snap-fit ​​engagement, or a top-pressing mechanism using pressure plate screws.

[0090] In this embodiment, the second acceleration module 41 is designed to be detachable. When the second acceleration module 41 is repaired or replaced, it is not necessary to remove the entire second cover plate 40 or perform a large-scale disassembly. The old second acceleration module 41 can be taken out, which greatly reduces the maintenance cost.

[0091] The plasma device provided in this embodiment, when the difference in free radical concentration on the workpiece surface is small, primarily uses the first acceleration module 12 to accelerate ions within the cross-section of the entire plasma generation space 21, thereby increasing the vertical velocity of free radicals reaching the entire workpiece surface and shortening the processing time. The second acceleration module 41 is used to adjust the free radical concentration in different areas of the workpiece surface to ensure the uniformity of the surface treatment effect. When the difference in free radical concentration on the workpiece surface is large, the first acceleration module 12 and the second acceleration module 41 can be used simultaneously to adjust the concentration, so as to achieve uniformity of free radical concentration on the workpiece surface as quickly as possible.

[0092] Other configurations of the plasma device in the above embodiments can be derived from various technical solutions now and in the future known to those skilled in the art, and will not be described in detail here.

[0093] In the description of this specification, it should be understood that the terms "center," "longitudinal," "transverse," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0094] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, "multiple" means two or more, unless otherwise explicitly specified.

[0095] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0096] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0097] The foregoing disclosure provides many different implementations or examples for carrying out different structures of this disclosure. To simplify the disclosure, specific examples of components and arrangements have been described above. Of course, these are merely examples and are not intended to limit the scope of this disclosure. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed.

[0098] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this disclosure, and these should all be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A plasma device, characterized in that, include: Medium cylinder; The first cover plate is installed on the upper part of the dielectric cylinder, and together with the dielectric cylinder, they form a plasma generation space; The first cover plate is provided with a first acceleration module; wherein, the first acceleration module includes: a first electrode, a first insulating layer and a first electrode feeder, wherein, the first insulating layer covers the first electrode, and the first electrode feeder is used to feed energy into the first electrode to form a first electric field, and the first electric field is used to adjust the vertical velocity of ions in the plasma from the plasma space to the workpiece processing space along the axis of the plasma device, thereby adjusting the vertical velocity of free radicals in the plasma; A coil, disposed on the outside of the dielectric cylinder, is used to excite the process gas in the plasma generation space into plasma; The housing is located below the medium cylinder; The second cover plate is connected to the lower part of the medium cylinder and covers the upper part of the box body, together with the box body forming a workpiece processing space; The grid is located between the plasma generation space and the workpiece processing space.

2. The plasma device according to claim 1, characterized in that, The first acceleration module is laid on the upper or lower surface of the first cover plate.

3. The plasma device according to claim 2, characterized in that, The orthographic projection of the first acceleration module on the upper surface of the first cover plate covers the orthographic projection of the workpiece on the upper surface of the first cover plate.

4. The plasma device according to claim 2, characterized in that, The orthographic projection of the first acceleration module onto the upper surface of the first cover plate covers the upper surface of the first cover plate.

5. The plasma device according to claim 1, characterized in that, The first electrode feeder is located on the side of the first acceleration module.

6. The plasma device according to claim 1, characterized in that, The first acceleration module has multiple components, at least two of which are arranged in a fan shape, and at least two of the first acceleration modules are arranged circumferentially along the first cover plate.

7. The plasma device according to claim 1, characterized in that, The first acceleration module has multiple components, at least two of which are arranged in a circular shape, and the multiple circular first acceleration modules are arranged concentrically.

8. The plasma device according to claim 1, characterized in that, The second cover plate is provided with at least one second acceleration module; wherein the second acceleration module includes: a second electrode, a second insulating layer and a second electrode feeder, wherein the second insulating layer covers the second electrode, and the second electrode feeder is used to feed energy into the second electrode to form a second electric field, the second electric field is used to adjust the horizontal velocity of ions in the plasma from the plasma space to the workpiece processing space, thereby adjusting the horizontal velocity of free radicals in the plasma; The second acceleration module is located above the grille.

9. The plasma device according to claim 8, characterized in that, The second acceleration module has multiple modules, and the multiple second acceleration modules are spaced apart and evenly distributed along a preset circumference; the diameter of the preset circumference is larger than the diameter of the space in the workpiece processing space.

10. The plasma device according to claim 9, characterized in that, Also includes: A first voltage control module is electrically connected to the first electrode feeder of the first acceleration module to control the intensity of the first electric field formed by the first electrode of the first acceleration module. The second voltage control module is electrically connected to the second electrode feeders of the multiple second acceleration modules to control the intensity of the second electric field formed by the second electrodes of the multiple second acceleration modules.

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