Plasma cleaning device

Abstract

The utility model provides a plasma cleaning device, and belongs to the technical field of semiconductor production equipment, the plasma cleaning device comprises a cavity, and a chamber is arranged in the cavity; the cover plate covers the upper end of the cavity; the remote plasma source is connected to the central position of the protruding part; the gas blocking part is arranged in the conical cavity; the first gas homogenizing plate is arranged below the gas blocking part; the second gas uniformizing plate is arranged below the first gas uniformizing plate; and a substrate table. The cover plate and the gas blocking part can uniformly disperse plasma gas fed by a remote plasma source into the cavity, then the plasma gas is further homogenized through the first gas homogenizing plate to ensure the gas uniformity of a substrate area, and meanwhile, the vacuum mechanism is generally connected to the bottom of the cavity, so that the gas is downwards pumped through the second gas homogenizing plate during gas pumping, and the gas uniformity of the substrate area is ensured. The gas uniformity in the chamber can be effectively ensured, so that the etching uniformity and the etching rate are improved.

Description

Technical Field

[0001] The present application belongs to the technical field of semiconductor production equipment, and specifically relates to a plasma cleaning device used in semiconductor production. Background Art

[0002] Semiconductors can be cleaned using ICP (Inductively Coupled Plasma). ICP technology utilizes a high-frequency electromagnetic field to generate plasma. Radio frequency electrodes ionize a working gas (such as argon, oxygen, or fluorine) to form a high-energy ion beam. This ion beam is focused by a collimating lens and precisely irradiated onto the semiconductor surface. Through collision and reaction, impurities and unwanted materials are removed. ICP technology is highly efficient and precise, enabling nanometer-scale etching.

[0003] In the related prior art, the ICP etching uniformity is insufficient, which affects the stability and performance of semiconductor processes and processing. Utility Model Content

[0004] The present application aims to solve at least one of the above-mentioned technical problems existing in the prior art. To this end, the present application provides a plasma cleaning device that can solve the problem of insufficient etching uniformity.

[0005] A plasma cleaning device according to an embodiment of the present application includes:

[0006] a cavity, wherein a chamber is provided inside the cavity;

[0007] a cover plate, the cover plate covering the upper end of the chamber, the cover plate being provided with an upwardly protruding portion, and a conical chamber being formed below the protruding portion;

[0008] a remote plasma source connected to a center position of the protrusion and in communication with the chamber;

[0009] An air blocking portion is provided in the conical chamber, wherein a conical head is provided at one end of the air blocking portion close to the remote plasma source, and a distance is provided between the conical head and the cover plate;

[0010] A first air equalizing plate, the first air equalizing plate being arranged below the air blocking portion, the first air equalizing plate being provided with a plurality of first air equalizing holes, the spacing between the first air equalizing holes decreasing from the center to the surrounding direction;

[0011] A second air equalizing plate, the second air equalizing plate being arranged below the first air equalizing plate, the second air equalizing plate being provided with a plurality of second air equalizing holes, and the center of the second air equalizing plate being provided with an opening;

[0012] The substrate stage is liftably arranged below the second air-distributing plate, and the substrate stage can support the substrate to move upward to the opening position.

[0013] According to the plasma cleaning device of the embodiment of the present application, there are at least the following beneficial effects: the plasma cleaning device of this embodiment, the arrangement of the cover plate and the air baffle can disperse the plasma gas sent into the chamber by the remote plasma source, and then further equalize the gas through the first gas equalizing plate to ensure the gas uniformity in the substrate area. At the same time, the vacuum mechanism is generally connected to the bottom of the cavity, so when pumping gas, the gas is pumped downward through the second gas equalizing plate, which can effectively ensure the gas uniformity in the chamber, thereby improving the etching uniformity and etching rate.

[0014] According to some embodiments of the present application, the inner side wall of the cover plate and / or the outer surface of the conical head are polished.

[0015] According to some embodiments of the present application, the air blocking portion is further provided with a support seat, which is connected between the conical head and the first air equalizing plate. The conical head protrudes outward relative to the support seat, thereby forming a shielding space between the support seat, and the conical head is provided with a third air equalizing hole. The upper end of the third air equalizing hole is located on the side wall of the conical head facing the cover plate, and the lower end is located on the side wall of the shielding space.

[0016] According to some embodiments of the present application, the channel of the third air equalizing hole is inclined relative to the vertical direction, and the distance between the upper end of the third air equalizing hole and the center of the support seat is greater than the distance between the lower end of the third air equalizing hole and the center of the support seat.

[0017] According to some embodiments of the present application, the horizontal projection of the protrusion completely covers the substrate mounting position on the substrate stage.

[0018] According to some embodiments of the present application, the second air equalizing holes are evenly distributed on the second air equalizing plate.

[0019] According to some embodiments of the present application, the second air equalizing plate is provided with a pressure plate, which extends into the opening. When the substrate table supports the substrate and moves upward to the opening, the pressure plate presses against the edges of the substrate and maintains a seal.

[0020] According to some embodiments of the present application, a plurality of vacuum ports are provided at the bottom of the cavity, the plurality of vacuum ports are evenly distributed at the bottom of the chamber, and each of the vacuum ports is provided with a pressure-regulating butterfly valve.

[0021] According to some embodiments of the present application, a plurality of ejector pins are vertically arranged in the chamber, and a clearance hole is provided in the substrate mounting position of the substrate stage. When the substrate stage moves downward, the ejector pins can pass through the clearance hole to lift the substrate.

[0022] According to some embodiments of the present application, the plasma cleaning device further includes:

[0023] a first magnetic coil, wherein the first magnetic coil is disposed at an upper end of the cover plate, and a projection of the first magnetic coil on a horizontal plane surrounds a substrate mounting position on the substrate stage;

[0024] a second magnetic coil, the second magnetic coil being arranged at the bottom of the cavity, the second magnetic coil being aligned with the first magnetic coil in vertical alignment;

[0025] The first magnetic coil and the second magnetic coil form a top-down magnetic field inside the coil.

[0026] Additional aspects and advantages of the present application will be given in part in the following description, and some additional aspects and advantages will become obvious from the following description, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present application is further described below with reference to the accompanying drawings and embodiments, wherein:

[0028] Figure 1 This is a schematic diagram of the overall structure of the present application;

[0029] Figure 2 A structural diagram of the air baffle portion;

[0030] Figure 3 Schematic diagram of the structure of the first air equalizing plate;

[0031] Figure 4 Schematic diagram of the structure of the second air equalizing plate;

[0032] Figure 5 A structural diagram of a cover plate;

[0033] Figure 6 A schematic diagram of the arrangement of a vacuum mechanism;

[0034] Figure 7 A schematic diagram of the structure for lowering the substrate stage. DETAILED DESCRIPTION

[0035] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0036] In the description of this application, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this application.

[0037] In the description of this application, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0038] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0039] In the description of this application, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0040] Reference Figure 1 The embodiment of the present application provides a plasma cleaning device, including a chamber 100, a cover plate 200, a remote plasma source 300, an air baffle 400, a first gas equalizing plate 500, a second gas equalizing plate 600 and a substrate stage 700. Specifically:

[0041] The cavity 100 is provided with a chamber 101 inside;

[0042] The cover plate 200 covers the upper end of the chamber 101 and forms the upper side wall of the chamber 101. The cover plate 200 is provided with an upwardly protruding portion 201, and a conical chamber 2011 is formed below the protruding portion 201.

[0043] The remote plasma source 300 is connected to the center of the protrusion 201 and communicates with the chamber 101 for delivering plasma gas into the chamber 101;

[0044] The air blocking portion 400 is disposed in the conical chamber 2011 . A conical head 401 is disposed at one end of the air blocking portion 400 close to the remote plasma source 300 . A distance is provided between the conical head 401 and the cover plate 200 .

[0045] The first air equalizing plate 500 is disposed below the air blocking portion 400 . The first air equalizing plate 500 is provided with a plurality of first air equalizing holes 501 . The spacing between the first air equalizing holes 501 decreases from the center to the periphery.

[0046] The second air equalizing plate 600 is disposed below the first air equalizing plate 500. A plurality of second air equalizing holes 602 are disposed on the second air equalizing plate 600, and an opening is disposed at the center of the second air equalizing plate 600.

[0047] The substrate stage 700 is disposed below the second air-distributing plate 600 in a liftable manner. The substrate stage 700 can support the substrate and move it upward to the opening position.

[0048] It can be understood that the chamber 101, the air blocking portion 400, the first air balancing plate 500, the second air balancing plate 600 and the substrate stage 700 are coaxially distributed. Figure 1 and Figure 5 A conical chamber 2011 is formed below the protruding portion 201 , that is, the upwardly protruding sidewall of the protruding portion 201 is an inclined surface, thereby forming the conical chamber 2011 .

[0049] The remote plasma source 300 is RPS, which is a device for generating plasma. It is usually used for surface treatment, material modification, thin film deposition and other processes in a vacuum environment. RPS generates plasma by using an electric field or a magnetic field by delivering gas into the device, and then transmits the plasma to the surface area that needs to be treated. Unlike traditional plasma sources, RPS usually does not directly contact the surface to be treated, but generates plasma at a certain distance and transmits the plasma to the target surface, so it is called "remote plasma source 300". The main advantage of the remote plasma source 300 is that it can achieve uniform treatment of the surface, and for some sensitive surfaces or materials, since it is far away from the plasma, the thermal and chemical damage to the surface is reduced. In addition, the remote plasma source 300 can be integrated into a vacuum processing system, making the surface treatment and material modification processes more flexible and efficient.

[0050] There is a distance between the conical head 401 of the air blocking portion 400 and the cover plate 200. Since the cover plate 200 forms a conical chamber 2011 through the protrusion 201 and the two are coaxially distributed, a uniform air flow channel is formed that guides the air from top to bottom to both sides.

[0051] Reference Figure 1 and Figure 3 Since the distance from the edge area of ​​the first gas equalizing plate 500 to the remote plasma source 300 is greater than the distance from the center area to the remote plasma source 300, the first gas equalizing holes 501 on the first gas equalizing plate 500 decrease in the direction from the center to the surrounding areas, so that the number of first gas equalizing holes 501 closer to the edge area is greater, which is beneficial to ensure the gas uniformity in the space below the first gas equalizing plate 500.

[0052] Therefore, the plasma cleaning device of this embodiment, the setting of the cover plate 200 and the gas blocking part 400 can disperse the plasma gas sent into the remote plasma source 300 into the chamber 101, and then further equalize the gas through the first gas equalizing plate 500 to ensure the gas uniformity in the substrate area.

[0053] At the same time, the vacuum mechanism is generally connected to the bottom of the cavity 100, so when pumping gas, the gas is pumped downward through the second gas uniformity plate 600, which can effectively ensure the uniformity of the gas in the chamber 101, thereby improving the etching uniformity and etching rate.

[0054] In some embodiments of the present application, the inner side wall of the cover plate 200 and / or the outer surface of the conical head 401 are polished. The polishing process can improve the surface smoothness, which is beneficial to improving the survival rate of plasma-active free radicals.

[0055] Reference Figure 1 and Figure 2 In some embodiments of the present application, the air blocking portion 400 is further provided with a support seat 402, and the support seat 402 is connected between the conical head 401 and the first air equalizing plate 500. The conical head 401 protrudes outward relative to the support seat 402, thereby forming a shielding space between the support seat 402, and the conical head 401 is provided with a third air equalizing hole 4011. The upper end of the third air equalizing hole 4011 is located on the side wall of the conical head 401 facing the cover plate 200, and the lower end is located on the side wall of the shielding space.

[0056] It is understood that the circumferential dimensions of the conical head 401 are larger than those of the support base 402, and a shielding space is formed below the conical head 401. The provision of the third gas equalization holes 4011 allows plasma gas to be delivered into the shielding space, preventing the conical head 401 from protruding significantly from the support base 402, which would hinder the efficient delivery of plasma gas. Plasma gas can enter the shielding space through the third gas equalization holes 4011 and be delivered downward along with the plasma gas within the conical chamber 2011, achieving a better gas equalization effect.

[0057] Moreover, since the conical head 401 is supported on the first gas equalizing plate 500 by the support seat 402, the circumferential size of the support seat 402 needs to be minimized on the basis of meeting the support requirements to avoid blocking the first gas equalizing hole 501. By setting the third gas equalizing hole 4011, this embodiment can effectively avoid the situation where the blocking space is too large and affects the delivery of plasma gas.

[0058] During the setting, the taper of the conical head 401 and the inclination angle of the protrusion 201 can be kept consistent, or other angle settings can be adopted.

[0059] Reference Figure 2 In some embodiments of the present application, the third gas equalizing holes 4011 are arranged at an angle relative to the vertical direction, and the distance between the upper end of the third gas equalizing holes 4011 and the center of the support base 402 is greater than the distance between the lower end of the third gas equalizing holes 4011 and the center of the support base 402. With the structural arrangement of this embodiment, the plasma gas flows toward the support base 402 through the third gas equalizing holes 4011 and can be transported downward along the outer surface of the support base 402.

[0060] Reference Figure 1 In some embodiments of the present application, the horizontal projection of the protrusion 201 completely covers the substrate mounting position on the substrate stage 700. This ensures 100% coverage of the substrate by the plasma gas, enabling large-area cleaning and improving cleaning efficiency. Specifically, the distance between the horizontal projection of the protrusion 201 and the edge of the substrate mounting position can be controlled to be 50 mm to 100 mm, thereby achieving a balance between overall size and coverage.

[0061] In some embodiments of the present application, the second gas equalizing holes 602 are evenly distributed on the second gas equalizing plate 600. During normal operation, the substrate is moved to the opening of the second gas equalizing plate 600 via the substrate stage 700. Therefore, the second gas equalizing plate 600 is mainly used for exhausting gas. The arrangement of evenly distributed second gas equalizing holes 602 can ensure uniform exhaust around the substrate and maintain the stability of the vacuum level in the chamber 101.

[0062] Reference Figure 1 and Figure 4In some embodiments of the present application, the second air equalizing plate 600 is provided with a pressure plate 601, which extends into the opening. When the substrate stage 700 supports the substrate and moves upward to the opening, the pressure plate 601 is pressed against the edges of the substrate and maintains a seal. It should be noted that the pressure plate 601 needs to be offset from the second air equalizing hole 602 to avoid blocking the second air equalizing hole 602. It is understandable that the pressure plate 601 can also be fixedly connected to the cavity 100.

[0063] Reference Figure 1 and Figure 6 In some embodiments of the present application, multiple vacuum ports are provided at the bottom of the chamber 100, evenly distributed at the bottom of the chamber 101, and each vacuum port is provided with a pressure-regulating butterfly valve 800. The pressure-regulating butterfly valve 800 can be used to adjust the suction of the vacuum port to maintain the process pressure required for the cleaning process, thereby ensuring the etching rate.

[0064] In most cases, the cavity 100 is a cubic structure, and the chamber 101 inside is a rectangular cavity. Therefore, the vacuum ports can be set at the four corners of the chamber 101.

[0065] Reference Figure 1 and Figure 7 In some embodiments of the present application, multiple ejector pins 702 are vertically disposed within the chamber 101, and a clearance hole 701 is provided within the substrate mounting position of the substrate stage 700. When the substrate stage 700 moves downward, the ejector pins 702 can pass through the clearance hole 701 to lift the substrate. This structural design allows the ejector pins 702 to automatically separate the substrate from the substrate stage 700, resulting in a simple structural design.

[0066] Reference Figure 1 In some embodiments of the present application, the plasma cleaning device further comprises:

[0067] A first magnetic coil 900 is disposed at the upper end of the cover plate 200 , and a projection of the first magnetic coil 900 on a horizontal plane surrounds the substrate mounting position on the substrate stage 700 ;

[0068] The second magnetic coil 1000 is disposed at the bottom of the cavity 100 and is aligned with the first magnetic coil 900 in a vertical direction.

[0069] The first magnetic coil 900 and the second magnetic coil 1000 form a top-down magnetic field inside the coils.

[0070] Because an electric field is applied to the substrate stage 700 during the process, this embodiment utilizes the first magnetic coil 900 and the second magnetic coil 1000. The combined action of the electric and magnetic fields allows charged ions to spiral along the magnetic field lines toward the substrate stage 700, thereby improving cleaning efficiency. It will be appreciated that the distance between the first magnetic coil 900 and the second magnetic coil 1000 can be varied to adjust the generated magnetic field lines, thereby adjusting the ion confinement effect.

[0071] The embodiments of the present application have been described in detail above with reference to the accompanying drawings. However, the present application is not limited to the above embodiments. Various modifications can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of the present application. In addition, the embodiments of the present application and the features of the embodiments can be combined with each other unless there is a conflict.

Claims

1. A plasma cleaning device, characterized in that: include: a cavity, wherein a chamber is provided inside the cavity; a cover plate, the cover plate covering the upper end of the chamber, the cover plate being provided with an upwardly protruding portion, and a conical chamber being formed below the protruding portion; a remote plasma source connected to a center position of the protrusion and in communication with the chamber; An air blocking portion is provided in the conical chamber, wherein a conical head is provided at one end of the air blocking portion close to the remote plasma source, and a distance is provided between the conical head and the cover plate; A first air equalizing plate, the first air equalizing plate being arranged below the air blocking portion, the first air equalizing plate being provided with a plurality of first air equalizing holes, the spacing between the first air equalizing holes decreasing from the center to the surrounding direction; A second air equalizing plate, the second air equalizing plate being arranged below the first air equalizing plate, the second air equalizing plate being provided with a plurality of second air equalizing holes, and the center of the second air equalizing plate being provided with an opening; The substrate stage is liftably arranged below the second air-distributing plate, and the substrate stage can support the substrate to move upward to the opening position.

2. The plasma cleaning device according to claim 1, characterized in that: The inner side wall of the cover plate and / or the outer surface of the conical head are polished.

3. The plasma cleaning device according to claim 1, characterized in that: The air-blocking portion is also provided with a support seat, which is connected between the conical head and the first air equalizing plate. The conical head protrudes outward relative to the support seat, thereby forming a shielding space between the support seat, and the conical head is provided with a third air equalizing hole. The upper end of the third air equalizing hole is located on the side wall of the conical head facing the cover plate, and the lower end is located on the side wall of the shielding space.

4. The plasma cleaning device according to claim 3, characterized in that: The channel of the third air equalizing hole is inclined relative to the vertical direction, and the distance between the upper end of the third air equalizing hole and the center of the support seat is greater than the distance between the lower end of the third air equalizing hole and the center of the support seat.

5. The plasma cleaning device according to claim 1, characterized in that: The horizontal projection of the protrusion completely covers the substrate mounting position on the substrate stage.

6. The plasma cleaning device according to claim 1, characterized in that: The second air equalizing holes are evenly distributed on the second air equalizing plate.

7. The plasma cleaning device according to claim 1, characterized in that: The second air equalizing plate is provided with a pressure plate, which extends into the opening. When the substrate table supports the substrate and moves upward to the opening, the pressure plate presses against the edges of the substrate and maintains a seal.

8. The plasma cleaning device according to claim 1, characterized in that: A plurality of vacuum ports are arranged at the bottom of the cavity, the plurality of vacuum ports are evenly distributed at the bottom of the cavity, and each of the vacuum ports is provided with a pressure regulating butterfly valve.

9. The plasma cleaning device according to claim 1, characterized in that: A plurality of ejector pins are vertically arranged in the chamber, and a clearance hole is provided in the substrate mounting position of the substrate stage. When the substrate stage moves downward, the ejector pins can pass through the clearance hole to lift the substrate.

10. The plasma cleaning device according to claim 1, wherein: The plasma cleaning device also includes: a first magnetic coil, wherein the first magnetic coil is disposed at an upper end of the cover plate, and a projection of the first magnetic coil on a horizontal plane surrounds a substrate mounting position on the substrate stage; a second magnetic coil, the second magnetic coil being arranged at the bottom of the cavity, the second magnetic coil being aligned with the first magnetic coil in vertical alignment; The first magnetic coil and the second magnetic coil form a top-down magnetic field inside the coil.

Images