A suction electrode for a high-current ion implanter

Abstract

The present invention relates to the technical field of semiconductor process equipment, and discloses a suction electrode for a large beam current ion implanter, which includes a ground electrode metal plate, a suppressor electrode metal plate, and an insulator disposed between the ground electrode metal plate and the suppressor electrode metal plate. A ground electrode shielding cylinder is provided on the ground electrode metal plate, and a suppressor electrode shielding cylinder is provided on the suppressor electrode metal plate. Both the ground electrode shielding cylinder and the suppressor electrode shielding cylinder are sleeved outside the insulator; one end of the ground electrode shielding cylinder has a first end plate for closing the ground electrode shielding cylinder; one end of the suppressor electrode shielding cylinder has a second end plate for closing the suppressor electrode shielding cylinder; the insulator is located between the first end plate and the second end plate. In the present invention, double-layer coating of the insulator is achieved, which not only effectively eliminates the possibility of conductive contaminants from the external space of the shielding cylinder attaching to the surface of the insulator, but also eliminates the adverse effects of conductive contaminants generated by the shielding cylinder itself on the insulator.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor process equipment, and particularly relates to a suction electrode for a high-current ion implanter. Background Art

[0002] The existing suction electrode structure of a high-current ion implanter mainly includes a ground electrode metal plate and a suppressor electrode metal plate. Usually, a high voltage of several thousand volts is applied between the ground electrode metal plate and the suppressor electrode metal plate to ensure that the secondary electrons generated when the ion beam bombards graphite when passing through the suction electrode slit can be incorporated into the ion beam and move together, making the ion beam electrically neutral and non-divergent. To isolate the high voltage, a cylindrical ceramic insulator is usually installed between the ground electrode metal plate and the suppressor electrode metal plate.

[0003] However, a lot of contaminated process substances are generated incidentally when the ion beam passes through the suction electrode. These contaminated process substances have conductive properties and are easily attached to the surface of the insulator, causing the insulation function of the insulator to fail. It is necessary to regularly remove the suction electrode from the equipment and replace it with a brand-new insulator. This process is not only time-consuming and laborious, reducing the production efficiency of the implanter, but also has a negative impact on the stability of the process.

[0004] Chinese invention patent with the publication number CN107808813A discloses an "insulation device for an extraction electrode", which includes the insulator by welding a metal shielding cylinder on the ground electrode metal plate, and at the same time, the structure of the insulator is modified to increase the insulation path length. Although this method extends the service life of the insulator to a certain extent, there are still defects. The shielding cylinder is made of metal, and conductive contaminants will still be generated during the process and attached to the surface of the insulator. In addition, the structure of the insulator is not optimized enough. Although the length of the insulation path has increased, the tortuosity of the insulation path is not high enough, which affects the service life of the suction electrode. Summary of the Invention

[0005] To solve the technical problems in the background art, the present invention proposes a suction electrode for a high-current ion implanter.

[0006] The suction electrode for a high-current ion implanter proposed by the present invention includes a ground electrode metal plate, a suppressor electrode metal plate, and an insulator disposed between the ground electrode metal plate and the suppressor electrode metal plate. Different from the prior art, a ground electrode shielding cylinder is provided on the ground electrode metal plate, a suppressor electrode shielding cylinder is provided on the suppressor electrode metal plate, and both the ground electrode shielding cylinder and the suppressor electrode shielding cylinder are sleeved outside the insulator;

[0007] One end of the ground electrode shielding cylinder has a first end plate for closing the ground electrode shielding cylinder. Specifically, the first end plate is fixed on the side of the ground electrode metal plate opposite to the suppressor electrode metal plate;

[0008] One end of the suppressor shield cylinder has a second end plate that closes the suppressor shield cylinder. Specifically, the second end plate is fixed on the side of the suppressor metal plate opposite to the ground electrode metal plate.

[0009] The insulator is located between the first end plate and the second end plate.

[0010] In some embodiments, specifically, the ground electrode shield cylinder has a portion sleeved outside the suppressor shield cylinder, and a first gap is formed between the inner side wall of the ground electrode shield cylinder and the outer side wall of the suppressor shield cylinder.

[0011] As a further optimized solution of the present invention, a first distance greater than zero is formed between the end of the suppressor shield cylinder far from the suppressor metal plate and the first end plate.

[0012] As a further optimized solution of the present invention, a second distance greater than zero is formed between the end of the ground electrode shield cylinder far from the ground electrode metal plate and the suppressor metal plate, and the first distance is not greater than the second distance.

[0013] As a further optimized solution of the present invention, a second gap is formed between the inner side surface of the suppressor shield cylinder and the outer side wall of the insulator, and the second gap is not less than the first gap.

[0014] In some embodiments, specifically, the suppressor shield cylinder has a portion sleeved outside the ground electrode shield cylinder, and the distance between the inner side wall of the suppressor shield cylinder and the outer side wall of the ground electrode shield cylinder is greater than zero.

[0015] As a further optimized solution of the present invention, the first end plate is installed on the ground electrode metal plate through a first fixing member, and the second end plate is installed on the suppressor metal plate through a second fixing member.

[0016] As a further optimized solution of the present invention, a first annular groove is formed on the outer side surface of the insulator.

[0017] As a further optimized solution of the present invention, the insulator has a first connecting portion, a middle connecting portion, and a second connecting portion. The middle connecting portion is located between the first connecting portion and the second connecting portion. The first connecting portion is connected to the ground electrode metal plate, and the second connecting portion is connected to the suppressor metal plate. The outer diameter of the middle connecting portion is greater than the outer diameters of the first connecting portion and the second connecting portion. A first stepped surface is formed between the middle connecting portion and the first connecting portion, and a second stepped surface is formed between the middle connecting portion and the second connecting portion. A second annular groove is formed on the first stepped surface and / or the second stepped surface.

[0018] As a further optimized solution of the present invention, a suppression electrode positioning groove matching the second end plate is formed on the suppression electrode metal plate, and / or:

[0019] A ground electrode positioning groove matching the first end plate is formed on the ground electrode metal plate.

[0020] In the present invention, the extraction electrode for a large beam current ion implanter realizes double-layer coating of the insulator by respectively installing shielding cylinders (including a ground electrode shielding cylinder and a suppression electrode shielding cylinder) on the ground electrode metal plate and the suppression electrode metal plate. This not only effectively eliminates the possibility of conductive contaminants from the external space of the shielding cylinder adhering to the surface of the insulator, but also eliminates the adverse effects of conductive contaminants generated by the shielding cylinder itself on the insulator.

[0021] Furthermore, the present invention also optimizes the structure of the insulator. Not only are second annular grooves provided on both side end faces, but also multiple first annular grooves are added on the side surface, effectively increasing the insulation path length and the tortuosity of the insulation path of the insulator, and greatly reducing the risk of path conduction of conductive contaminants to the insulator itself. The present invention significantly improves the service life of the extraction electrode, extends the maintenance period, saves a large amount of time, improves the production utilization rate of the large beam current ion implanter, and reduces the frequency of manual maintenance.

[0022] The additional aspects and advantages of the present invention will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a partial sectional view of the structure of the present invention;

[0024] Figure 2 is an exploded view of the structure of the present invention;

[0025] Figure 3 is a schematic diagram of the structure of the ground electrode metal plate of the present invention;

[0026] Figure 4 is a schematic diagram of the structure of the suppression electrode metal plate of the present invention;

[0027] Figure 5 is a schematic diagram of the structure of the ground electrode shielding cylinder of the present invention;

[0028] Figure 6 is a schematic diagram of the structure of the suppression electrode shielding cylinder of the present invention;

[0029] Figure 7 is a schematic diagram of the structure of the insulator of the present invention;

[0030] In the figure: 1. Earth electrode metal plate; 10. Earth electrode positioning groove; 2. Suppressor electrode metal plate; 20. Suppressor electrode positioning groove; 3. Insulator; 30. Middle connecting part; 31. First connecting part; 32. Second connecting part; 300. First annular groove; 301. Second annular groove; 4. Earth electrode shielding cylinder; 40. First end plate; 5. Suppressor electrode shielding cylinder; 50. Second end plate; 6. First fixing member; 7. Second fixing member. Specific embodiments

[0031] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, in which the same or similar symbols represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as limiting the present invention.

[0032] As Figures 1-7 shown, an extraction electrode for a large beam current ion implanter includes an earth electrode metal plate 1, a suppressor electrode metal plate 2, and an insulator 3 disposed between the earth electrode metal plate 1 and the suppressor electrode metal plate 2. The insulator 3 is made of ceramic material, and the earth electrode metal plate 1 and the suppressor electrode metal plate 2 are disc-shaped. An earth electrode shielding cylinder 4 is provided on the earth electrode metal plate 1, and a suppressor electrode shielding cylinder 5 is provided on the suppressor electrode metal plate 2. Both the earth electrode shielding cylinder 4 and the suppressor electrode shielding cylinder 5 are sleeved outside the insulator 3;

[0033] One end of the earth electrode shielding cylinder 4 has a first end plate 40 that closes the earth electrode shielding cylinder 4. Specifically, the first end plate 40 is fixed to the opposite side of the earth electrode metal plate 1 and the suppressor electrode metal plate 2 through a first fixing member 6;

[0034] One end of the suppressor electrode shielding cylinder 5 has a second end plate 50 that closes the suppressor electrode shielding cylinder 5. Specifically, the second end plate 50 is fixed to the opposite side of the suppressor electrode metal plate 2 and the earth electrode metal plate 1 through a second fixing member 7;

[0035] It should be noted here that the first fixing member 6 and the second fixing member 7 can be existing fixing members such as screws that can realize the connection of two components;

[0036] The insulator 3 is located between the first end plate 40 and the second end plate 50;

[0037] To achieve a better shielding effect, the ground electrode shielding cylinder 4 and the suppressor electrode shielding cylinder 5 are arranged in a nested structure. Specifically, in this embodiment, the ground electrode shielding cylinder 4 has a portion sleeved outside the suppressor electrode shielding cylinder 5, and a first gap is formed between the inner side wall of the ground electrode shielding cylinder 4 and the outer side wall of the suppressor electrode shielding cylinder 5. Of course, those skilled in the art can also set it as: the suppressor electrode shielding cylinder 5 has a portion sleeved outside the ground electrode shielding cylinder 4, and the distance between the inner side wall of the suppressor electrode shielding cylinder 5 and the outer side wall of the ground electrode shielding cylinder 4 is greater than zero (this situation is not shown in the figure);

[0038] During the installation process, first fix the ground electrode shielding cylinder 4 on the ground electrode metal plate 1 through the first fixing member 6, then fix the suppressor electrode shielding cylinder 5 on the suppressor electrode metal plate 2 through the second fixing member 7, then fix one end of the insulator 3 on the ground electrode metal plate 1 or the suppressor electrode metal plate 2 by screws, and then fix the other end of the insulator 3 on the suppressor electrode metal plate 2 or the ground electrode metal plate 1 by screws. It should be noted that the screw penetrates through the ground electrode metal plate 1 and the first end plate 40 and is threadedly connected to the insulator 3, and the screw penetrates through the suppressor electrode metal plate 2 and the second end plate 50 and is connected to the insulator 3; while installing the insulator 3, the fixation between the suppressor electrode metal plate 2 and the ground electrode metal plate 1 is achieved, and high-voltage electrical isolation is realized through the insulator 3 between the ground electrode metal plate 1 and the suppressor electrode metal plate 2;

[0039] By installing shielding cylinders (including the ground electrode shielding cylinder 4 and the suppressor electrode shielding cylinder 5) on the ground electrode metal plate 1 and the suppressor electrode metal plate 2 respectively, double-layer coating of the insulator 3 is achieved, which not only effectively eliminates the possibility of conductive contaminants from the external space of the shielding cylinder attaching to the surface of the insulator 3, but also eliminates the adverse effects of conductive contaminants generated by the shielding cylinder itself on the insulator 3.

[0040] Preferably, there are at least three groups of the insulator 3, the suppressor electrode shielding cylinder 5 and the ground electrode shielding cylinder 4 between the ground electrode metal plate 1 and the suppressor electrode metal plate 2. One group of the ground electrode shielding cylinder 4, one group of the suppressor electrode shielding cylinder 5 and one group of the insulator 3 correspond to each other, and a gap is formed between any two adjacent groups of the insulator 3, thereby ensuring the stability of the connection between the ground electrode metal plate 1 and the suppressor electrode metal plate 2.

[0041] Preferably, a first distance greater than zero is formed between the end of the suppressor electrode shielding cylinder 5 far from the suppressor electrode metal plate 2 and the first end plate 40.

[0042] Preferably, a second distance greater than zero is formed between the end of the ground electrode shielding cylinder 4 far from the ground electrode metal plate 1 and the suppressor electrode metal plate 2, and the first distance is not greater than the second distance.

[0043] Preferably, a second gap is formed between the inner side surface of the suppressor electrode shielding cylinder 5 and the outer side wall of the insulator 3, and the second gap is not less than the first gap.

[0044] Preferably, a first annular groove 300 is formed on the outer side surface of the insulator 3. There are multiple groups of the first annular grooves 300, and a gap is formed between any two adjacent groups of the first annular grooves 300.

[0045] Furthermore, the insulator 3 has a first connecting portion 31, a middle connecting portion 30, and a second connecting portion 32. The middle connecting portion 30 is located between the first connecting portion 31 and the second connecting portion 32. The first connecting portion 31 is connected to the ground electrode metal plate 1. The first annular groove 300 is formed on the outer side of the middle connecting portion. The second connecting portion 32 is connected to the suppression electrode metal plate 2. The outer diameter of the middle connecting portion 30 is larger than the outer diameters of the first connecting portion 31 and the second connecting portion 32. A first stepped surface is formed between the middle connecting portion and the first connecting portion 31, and a second stepped surface is formed between the middle connecting portion and the second connecting portion 32. A second annular groove 301 is formed on the first stepped surface and the second stepped surface.

[0046] The insulation path length and the insulation path tortuosity of the insulator 3 are effectively increased, and the path conduction risk of conductive contaminants to the insulator 3 itself is greatly reduced. The service life of the suction electrode of the present invention is significantly increased, the maintenance period is extended, a large amount of time is saved, the production utilization rate of the large beam current ion implanter is increased, and the frequency of manual maintenance is reduced.

[0047] Preferably, in order to position the suppression electrode shielding cylinder 5, a suppression electrode positioning groove 20 matching the second end plate 50 is formed on the suppression electrode metal plate 2.

[0048] In order to position the ground electrode shielding cylinder 4, a ground electrode positioning groove 10 matching the first end plate 40 is formed on the ground electrode metal plate 1. During the installation process, the second end plate 50 of the suppression electrode shielding cylinder 5 is placed in the suppression electrode positioning groove 20, and the second end plate 50 is fixed to the suppression electrode metal plate 2 by screws (second fixing member 7). The first end plate 40 is placed in the ground electrode positioning groove 10 and the first end plate 40 is fixed to the ground electrode metal plate 1 by screws (second fixing member 7).

[0049] 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", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present invention.

[0050] In addition, 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 quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0051] In the present invention, unless otherwise clearly specified and defined, terms such as "mounted", "connected", "coupled", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or communicable with each other; it may be directly connected, or indirectly connected through an intermediate medium, and may be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher level height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower level height than the second feature.

[0053] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A suction electrode for a large beam current ion implanter, comprising a ground electrode metal plate (1) and a suppressor electrode metal plate (2) and an insulator (3) arranged between the ground electrode metal plate (1) and the suppressor electrode metal plate (2), characterized in that: The ground electrode metal plate (1) is provided with a ground electrode shielding tube (4), the suppressing electrode metal plate (2) is provided with a suppressing electrode shielding tube (5), and the ground electrode shielding tube (4) and the suppressing electrode shielding tube (5) are both sleeved outside the insulator (3); One end of the ground electrode shielding cylinder (4) has a first end plate (40) for closing the ground electrode shielding cylinder (4); One end of the suppressor shielding tube (5) has a second end plate (50) for closing the suppressor shielding tube (5); The insulator (3) is located between the first end plate (40) and the second end plate (50).

2. The suction electrode for a large beam current ion implanter according to claim 1, characterized in that: The ground electrode shielding cylinder (4) has a portion which is sleeved on the outside of the suppressing electrode shielding cylinder (5), and a first gap is formed between the inner side wall of the ground electrode shielding cylinder (4) and the outer side wall of the suppressing electrode shielding cylinder (5).

3. The suction electrode for a large beam current ion implanter according to claim 2, characterized in that: A first distance greater than zero is formed between one end of the suppressor shielding cylinder (5) away from the suppressor metal plate (2) and the first end plate (40).

4. The suction electrode for a large beam current ion implanter according to claim 3, characterized in that: A second distance greater than zero is formed between one end of the ground electrode shielding cylinder (4) away from the ground electrode metal plate (1) and the suppression electrode metal plate (2), and the first distance is not greater than the second distance.

5. The suction electrode for a large beam current ion implanter according to claim 2, characterized in that: A second interval is formed between the inner side surface of the suppressor shielding cylinder (5) and the outer side wall of the insulator (3), and the second interval is not smaller than the first interval.

6. The suction electrode for a large beam current ion implanter according to claim 1, characterized in that: The suppressor shielding tube (5) has a portion which is sleeved on the outside of the grounding shielding tube (4), and the distance between the inner wall of the suppressor shielding tube (5) and the outer wall of the grounding shielding tube (4) is greater than zero.

7. The suction electrode for a large beam current ion implanter according to claim 1, characterized in that: The first end plate (40) is mounted on the ground electrode metal plate (1) via a first fixing member (6), and the second end plate (50) is mounted on the suppression electrode metal plate (2) via a second fixing member (7).

8. The suction electrode for a large beam current ion implanter according to claim 1, characterized in that: The outer side surface of the insulator (3) is provided with a first annular groove (300).

9. The suction electrode for a large beam current ion implanter according to claim 1, characterized in that: The insulator (3) comprises a first connection portion (31), a middle connection portion (30) and a second connection portion (32); the middle connection portion (30) is located between the first connection portion (31) and the second connection portion (32); the first connection portion (31) is connected to the ground electrode metal plate (1); the second connection portion (32) is connected to the suppression electrode metal plate (2); the outer diameter of the middle connection portion (30) is greater than the outer diameters of the first connection portion (31) and the second connection portion (32); a first stepped surface is formed between the middle connection portion and the first connection portion (31); a second stepped surface is formed between the middle connection portion and the second connection portion (32); and a second annular groove (301) is provided on the first stepped surface and / or the second stepped surface.

10. The suction electrode for a large beam current ion implanter according to claim 1, characterized in that: The suppressor metal plate (2) is provided with a suppressor positioning groove (20) matching the second end plate (50); and / or: The ground electrode metal plate (1) is provided with a ground electrode positioning groove (10) matching the first end plate (40).

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