Ion beam system with multiple ion sources integrated

Abstract

The invention discloses an ion beam system of a multi-ion source set, which belongs to the technical field of ion implantation and comprises at least two groups of mass analysis magnets, a leading-out system is correspondingly arranged on the upstream side of each group of mass analysis magnets, and an ion source is correspondingly arranged on the upstream side of each leading-out system; an expansion coil magnet is correspondingly arranged on the downstream side of each group of mass analysis magnets; a collimation coil magnet is arranged on the downstream side of the expansion coil magnet. The problem that an existing multi-ion-source beam collection mode needs to be further optimized is solved, the better beam collection effect is achieved, the system is more stable, ion beams with the higher effective height and the larger flow intensity can be formed easily, and the multi-ion-source beam collection device is particularly suitable for the large-area ion implantation technology.

Description

Technical Field

[0001] The present invention belongs to the technical field of ion implantation, and particularly relates to an ion beam system integrating multiple ion sources. Background Art

[0002] Ion implantation (or ion implantation) means shooting an ion beam at a solid material (generally called a target, a substrate or a wafer), and finally staying in the solid material. At present, large-area implantation is a development direction of ion implantation, which is particularly important for the manufacturing process of large-area OLED displays. Therefore, it is required that the ribbon-shaped ion beam generated by the ion beam system has a sufficiently high effective height and a sufficiently large ion current intensity (that is, the number of ions shooting at the target per unit time is sufficiently large). Related prior arts include, for example, the Chinese invention patent with the application publication number CN114300331A. The present invention aims to provide a technical solution with a different main technical concept, and further achieve a better multi-ion source beam current integration effect. Summary of the Invention

[0003] Based on the technical problems existing in the prior art, the present invention provides an ion beam system integrating multiple ion sources, which solves the problem that the existing multi-ion source beam current integration method still needs to be further optimized, realizes a better beam current integration effect, and the system is more stable.

[0004] According to the technical solution of the present invention, an ion beam system integrating multiple ion sources is provided, which includes at least two groups of mass analysis magnets. An extraction system is correspondingly arranged on the upstream side of each group of mass analysis magnets, and an ion source is correspondingly arranged on the upstream side of the extraction system; An expansion coil magnet is correspondingly arranged on the downstream side of each group of mass analysis magnets; A collimating coil magnet is arranged on the downstream side of the expansion coil magnet.

[0005] Further, there is one group of collimating coil magnets, and the collimating coil magnets are located at the beam current intersection. The ion beams formed by all ion sources intersect at the beam current intersection in the width direction of the ion beam cross-section.

[0006] Further, different groups of mass analysis magnets are independent of each other.

[0007] Preferably, there are two groups of mass analysis magnets, namely a first mass analysis magnet and a second mass analysis magnet; And the mass analysis magnets are arranged such that for the same ion beam, the deflection direction of the ion beam flowing through the first mass analysis magnet is opposite to the deflection direction of the ion beam flowing through the second mass analysis magnet.

[0008] Preferably, on the upstream side of at least one set of mass analysis magnets, there are at least two ion sources, and the ion sources are arranged at an angle to make the ion beams flowing through the same mass analysis magnet spaced apart in the cross-sectional length direction at the collimating coil magnet.

[0009] According to some embodiments, there are two sets of mass analysis magnets, namely the first mass analysis magnet and the second mass analysis magnet; on the upstream side of at least one set of mass analysis magnets, there are at least two ion sources, and the ion sources are arranged at an angle to make the ion beams flowing through the same mass analysis magnet spaced apart in the cross-sectional length direction at the collimating coil magnet; at the collimating coil magnet, the ion beam flowing through the first mass analysis magnet intersects and joins with the ion beam flowing through the second mass analysis magnet in the cross-sectional length direction to form a continuous strip-shaped cross-section.

[0010] Further, there are two ion sources on the upstream side of the first mass analysis magnet, namely the first ion source and the second ion source, and the output directions of the first ion source and the second ion source are close to each other on the output side and far from each other on the input side; there are two ion sources on the upstream side of the second mass analysis magnet, namely the third ion source and the fourth ion source, and the output directions of the third ion source and the fourth ion source are close to each other on the output side and far from each other on the input side; on the downstream side of the collimating coil magnet, the ion beam of the first ion source and the ion beam of the second ion source are spaced apart, and the ion beam of the third ion source and the ion beam of the fourth ion source are spaced apart; and, one of the ion beam of the third ion source and the ion beam of the fourth ion source is located between the ion beam of the first ion source and the ion beam of the second ion source, and the other is located outside the ion beam of the first ion source and the ion beam of the second ion source; so as to form a strip-shaped ion beam with a continuous cross-section formed by connecting four segments of ion beams.

[0011] Further, a set of expansion coil magnets on the downstream side of the first mass analysis magnet are the first expansion coil and the second expansion coil, and the first expansion coil and the second expansion coil are respectively located on both sides of the ion beam flowing through the first mass analysis magnet; a set of expansion coil magnets on the downstream side of the second mass analysis magnet are the third expansion coil and the fourth expansion coil, and the third expansion coil and the fourth expansion coil are respectively located on both sides of the ion beam flowing through the second mass analysis magnet; the collimating coil magnet is located at the beam intersection, and the ion beams formed by all ion sources intersect at the beam intersection in the cross-sectional width direction of the ion beam; the collimating coil magnet is the first collimating coil and the second collimating coil, and the first collimating coil and the second collimating coil are located on the outer sides of all the intersecting ion beams.

[0012] Preferably, the mass analysis magnets are an even number of sets and are arranged symmetrically by mirror image; the corresponding ion sources, extraction systems, expansion coil magnets, and collimating coil magnets are also arranged symmetrically by mirror image.

[0013] Preferably, the ion source, extraction system, mass analysis magnet, expansion coil magnet, and collimating coil magnet are all arranged on the vacuum chamber; and / or, a vacuum valve is arranged between the extraction system and the mass analysis magnet.

[0014] Compared with the prior art, the beneficial technical effects of the multi-ion source integrated ion beam system of the present invention are as follows:

[0015] 1. The multi-ion source integrated ion beam system of the present invention uses at least two sets of mass analysis magnets, with better beam current integration effect, more stable system, and is helpful for forming an ion beam with a higher effective height and larger beam current, which can play a key role in the development and application of large-area ion implantation processes; taking the design with two sets of mass analysis magnets as an example (hereinafter described as left and right for distinction), the left mass analysis magnet adjusts the deflection angle of the beam current extracted from the left ion source, and the same applies to the right ion source and mass analysis magnet. In this way, the deflection angles of the left / right ion beams can be independently and finely controlled by adjusting the mass analysis magnets respectively.

[0016] 2. In the multi-ion source integrated ion beam system of the present invention, the paths of the left / right beam currents can be independently fine-tuned, so that the left / right beam currents have better passing performance through the expansion coil and collimating coil, while the existing scheme of using one mass analysis magnet to control the deflection of multiple sets of beam currents cannot achieve independent adjustment; in addition, when the left / right beam currents converge at the focus of the collimating coil, the intersection angle of the left / right beam currents can be fine-tuned, and the beam current foci of the two angles of the left / right can be adjusted to the same position as much as possible, so that it is easier for the collimating coil to adjust the beam current uniformity.

[0017] 3. In the multi-ion source integrated ion beam system of the present invention, the independent mass analysis magnet can also adjust the slight deviations that may exist due to processing and installation of the ion source and extraction system, as well as accurately adjust the beam current route and other situations, so that the efficiency of the integrated beam current is also higher than the existing scheme using one mass analysis magnet.

[0018] 4. For the existing scheme with one set of mass analysis magnets, multiple side-by-side ion sources need to be installed on the vacuum chamber of the same mass analysis magnet. In order to obtain the required deflection angle, the left and right ion sources need a certain installation space and incident angle. The side-by-side ion sources must be designed with different incident angles and a certain installation distance needs to be pulled apart horizontally, so a relatively large installation distance is required. In the multi-ion source integrated ion beam system of the present invention, taking the preferred two sets of mass analysis magnets as an example, due to the symmetric design of the left deflection to the left and the right deflection to the right, the installation of the ion source no longer needs to consider the space interference and angle problems between the left and right, and the connection structure and chamber design can also be simpler. Therefore, compared with the prior art, the present invention can shorten the distance between the ion source and the mass analysis magnet, and the ion beam transmission efficiency is higher. Brief Description of the Drawings

[0019] Figure 1 FIG. 1 is a schematic three-dimensional structure diagram of an ion beam system provided according to the present invention.

[0020] Figure 2 FIG. 2 is a schematic diagram of the structural principle from a top-down perspective of the ion beam system provided according to the present invention.

[0021] Figure 3 FIG. 3 is a schematic diagram of the structural principle from a side perspective of the ion beam system provided according to the present invention.

[0022] Figure 4 FIG. 4 is a schematic three-dimensional diagram of the overall structure of the ion beam system provided according to the present invention.

[0023] Figure 5 FIG. 5 is a schematic cross-sectional diagram in the horizontal direction of the overall structure of the ion beam system provided according to the present invention.

[0024] Figure 6 FIG. 6 is a schematic longitudinal cross-sectional diagram of the ion source, extraction system, vacuum valve, and mass analysis magnet part provided according to the present invention.

[0025] Explanation of the reference numerals in the drawings:

[0026] 1. Ion source; 2. Extraction system; 3. Mass analysis magnet; 4. Expansion coil magnet; 5. Collimation coil magnet; 6. Vacuum valve; 7. Transition cavity; 8. Faraday cup. Detailed Embodiments

[0027] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts fall within the scope of protection of the present invention.

[0028] In addition, it should be noted that for ease of description, only parts related to the relevant invention are shown in the drawings. Without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0029] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules, or units, and are not used to limit the order of the functions performed by these devices, modules, or units or their interdependent relationships.

[0030] It should be noted that the modifiers "a" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that, unless clearly specified otherwise in the context, it should be understood as "one or more".

[0031] The present invention discloses an ion beam system with a multi-ion source assembly, belonging to the technical field of ion implantation in semiconductor device manufacturing. It includes at least two sets of mass analysis magnets; a extraction system is correspondingly arranged on the upstream side of each set of mass analysis magnets, and an ion source is correspondingly arranged on the upstream side of the extraction system; a expansion coil magnet is correspondingly arranged on the downstream side of each set of mass analysis magnets; a collimating coil magnet is arranged on the downstream side of the expansion coil magnet. The present invention aims to solve the problem that the existing multi-ion source beam combination method needs to be further optimized, proposes a technical solution with a different main technical concept, realizes a better beam combination effect, the system is more stable, and helps to form an ion beam with a higher effective height and a larger beam current, especially suitable for large-area ion implantation processes. Large-area ion implantation processes, for example, are involved in the manufacturing process of large-area OLED displays, and require the strip-shaped ion beam generated by the ion beam system to have a sufficiently high effective height and a sufficiently large ion beam current (that is, the number of ions hitting the target wafer per unit time is sufficient); and as the size of the substrate to be processed increases, the requirements for the effective height of the ion beam, the ion implantation dose, and the density distribution uniformity are more stringent, and the existing solutions cannot better meet the ion implantation requirements of current and future high-end processes.

[0032] Please refer to Figures 1 to 3 , an ion beam system with a multi-ion source assembly of the present invention is used to form an ion beam that meets the requirements of the desired ion species, ion concentration (or ion density), ion beam height, shape, etc. The most significant difference between the present invention and the existing ion beam system is that an ion beam system with a multi-ion source assembly includes at least two sets of mass analysis magnets 3. Furthermore, a extraction system 2 is correspondingly arranged on the upstream side of each set of mass analysis magnets 3, and an ion source 1 is correspondingly arranged on the upstream side of the extraction system 2; a set of expansion coil magnets 4 is correspondingly arranged on the downstream side of each set of mass analysis magnets 3; a collimating coil magnet 5 is arranged on the downstream side of the expansion coil magnets 4. Thus, a structure is formed in which the ion source 1, the extraction system 2, the mass analysis magnets 3, the expansion coil magnets 4, and the collimating coil magnet 5 are arranged in sequence along the ion beam traveling direction. The basic structure of this solution can also be understood as having at least two sets of ion sources 1, extraction systems 2, mass analysis magnets 3, and expansion coil magnets 4. The components within each set correspond to each other, and the components in different sets can be considered independent. Thus, at least two / two sets of ion beams are formed based on at least two sets of mass analysis magnets 3, and finally all the ion beams are collimated by the same set of collimating coil magnets 5.

[0033] The ion source 1 is used to form a plasma. The extraction system 2, such as an extraction electrode, is used to provide an extraction electric field, and then extract the ions generated by the ion source 1 to form an ion beam. The mass analysis magnet 3 (AMU) is used to form an analysis magnetic field, so that the ion beam deflects when passing through it, and impurities in the ion beam are screened out during the travel of the ion beam, and a relatively pure ion beam of the required ions is obtained. The expansion coil magnet 4 is used to expand and stretch the ion beam, increase the height of the ion beam, and form a divergent ribbon-shaped ion beam. The structure of this system is set so that the ion beams flowing through different mass analysis magnets 3 gradually approach each other along the travel direction, and will pass through the corresponding expansion coil magnet 4 during the travel for expansion and stretching, and finally pass through a group of collimating coil magnets 5, and when the ion beam travels to the collimating coil magnets 5, it reaches the required height. The collimating coil magnets 5 (uniformity coils) are used to collimate and deflect the ion beam, make the travel directions of the ions in the ion beam parallel to each other, and can increase the uniformity, and finally obtain the required parallel ribbon-shaped ion beam.

[0034] More specifically, the collimating coil magnets 5 are a group, and the collimating coil magnets 5 are located at the beam intersection; the beam intersection means that the ion beams formed by all the ion sources 1 intersect at the beam intersection in the width direction of the ion beam cross-section. For the convenience of description and understanding, the orientation in the figure is used for description in this article; it should be noted that in actual applications, this system can be arranged at various angles according to needs to obtain the ion beam with the required travel direction and cross-section length direction. Please refer to Figure 1 , Figure 2 , from the top / down perspective, each ion beam is relatively thin, which is the cross-section width of the ion beam. The cross-section width direction of the ion beam is the direction on both sides of the travel direction of the ribbon-shaped ion beam. For the finally output ion beam, it is generally the Figure 2 up and down direction in; the ion beams flowing through different mass analysis magnets 3 gradually approach each other as they travel and coincide or nearly coincide at the collimating coil magnets 5 ( Figure 2 is a schematic diagram, and in order to show the ion beam path, it is not drawn as coinciding).

[0035] The present invention realizes the aggregation of two or more ion sources by setting two groups (or more groups) of mass analysis magnets 3. Compared with the prior art that controls the deflection of multiple ion beams through a magnetic lens, it can make the ion beam situation more ideal, such as the path is more precisely controllable, and thus the finally obtained aggregated ion beam also has better quality. Preferably, different groups of mass analysis magnets 3 are independent of each other for more precise adjustment; being independent means that the parameters of different groups of mass analysis magnets 3 are respectively controllable. For example, the mass analysis magnet is generally an electromagnet formed by a coil, and the analysis magnetic field formed can be adjusted by adjusting the current, and then the deflection of the ion beam, the screening of impurities, etc. can be adjusted.

[0036] In a preferred specific embodiment, there are two sets of mass analysis magnets 3, namely a first mass analysis magnet and a second mass analysis magnet respectively; and the mass analysis magnets 3 are arranged such that for the same ion beam, the deflection direction of the ion beam flowing through the first mass analysis magnet is opposite to that of the ion beam flowing through the second mass analysis magnet. The opposite deflection directions mean that the directions are opposite and point away from each other. For example Figure 2 as shown, the upper ion beam is generally deflected upward and the lower ion beam is generally deflected downward. This solution is more convenient for the spatial layout of each component, and this reasonable spatial layout is beneficial to the efficiency and stability of the system. More specifically, the method and principle for achieving opposite deflection directions are that the analysis magnetic fields formed by the two sets of mass analysis magnets 3 are generally in opposite directions, and the Lorentz forces received by the same moving charged particles in opposite magnetic fields are in opposite directions.

[0037] In some more preferred specific embodiments, please refer to Figure 1 , Figure 3 , for at least two sets of mass analysis magnets 3, on the upstream side of at least one set of mass analysis magnets 3, there are at least two ion sources 1 (forming a set of ion sources corresponding to this mass analysis magnet 3), and the ion sources 1 are arranged at an angle so that at the collimation coil magnet 5, the ion beams flowing through the same mass analysis magnet are spaced apart (not coincident, not overlapping) in the cross-sectional length direction; furthermore, the ion beams flowing through different mass analysis magnets form an overall ion beam with the required height (i.e., cross-sectional length) through splicing and / or coincidence and / or overlap.

[0038] More specifically, please refer to Figure 3 , which is a schematic diagram. The dotted line only shows the approximate center line of the ion beam path and does not draw the height of the ion beam. The actual ion beam will expand in the height direction, so as to finally form the required strip cross-section; the ion beams formed by a set of ion sources can be regarded as independent of each other, that is, the ion beam paths of each ion source are independent of each other, and the ion beam paths can be selected to cross; this cross-sectional structure form with the output sides of the ion sources close to each other is also beneficial to the spatial layout. As a supplementary explanation, the ion source and the extraction system can adopt the prior art. The typical structure includes that the output side of each ion source 1 has a cover plate, and the cover plate has a through, strip-shaped extraction slit. The extraction system 2 is located outside the extraction slit. The extraction system 2 and the ion beam 1 are generally set in a complete set corresponding to each other, and are set so that the extracted ion beam is basically consistent with the length direction of the ion source and basically perpendicular to the cover plate plane where the extraction slit is located. Therefore, in the layout of multiple ion sources in this solution, the length directions of the extraction slits are generally longitudinal, and the cover plate planes form a certain angle (not zero degree, not parallel). Such a longitudinal arrangement realizes the above-mentioned ion beam path and other effects.

[0039] In a further preferred embodiment, there are two sets of mass analysis magnets 3, namely a first mass analysis magnet and a second mass analysis magnet; on the upstream side of at least one set of the mass analysis magnets 3, there are at least two ion sources 1, and the ion sources 1 are arranged at an angle to make the ion beams flowing through the same mass analysis magnet spaced apart in the cross-sectional length direction at the collimating coil magnet 5; the ion beam flowing through the first mass analysis magnet intersects and connects with the ion beam flowing through the second mass analysis magnet in the cross-sectional length direction at the collimating coil magnet 5 to form a continuous strip-shaped cross-section.

[0040] The following will be further described in conjunction with Figures 1 to 6 the specific structure shown. Among them, two ion sources 1 (for the convenience of description, called the first group of ion sources) are provided on the upstream side of the first mass analysis magnet, namely a first ion source and a second ion source, and the output directions of the first ion source and the second ion source are close to each other on the output side and far from each other on the input side; similarly, two ion sources 1 (for the convenience of description, called the second group of ion sources) are provided on the upstream side of the second mass analysis magnet, namely a third ion source and a fourth ion source, and the output directions of the third ion source and the fourth ion source are close to each other on the output side and far from each other on the input side. An extraction system 2 is respectively arranged on the output side of each ion source 1. On the downstream side of the collimating coil magnet 5, the ion beam of the first ion source and the ion beam of the second ion source are spaced apart, and the ion beam of the third ion source and the ion beam of the fourth ion source are spaced apart; and, one of the ion beam of the third ion source and the ion beam of the fourth ion source is located between the ion beam of the first ion source and the ion beam of the second ion source, and the other is located outside the ion beam of the first ion source and the ion beam of the second ion source; so as to form a strip-shaped ion beam with a continuous strip-shaped cross-section formed by the connection of four ion beams.

[0041] Among the first group of ion sources and the second group of ion sources, the traveling modes of the two ion beams of one of them are as Figure 3 shown, and the two ion beams of the other are similar but at different angles from Figure 3 it, so that a total of four ion beams are spliced to form an overall ion beam with the required length; assuming that a substrate to be injected is placed on the downstream side of the collimating coil magnet 5, that is, the output side of the required ion beam finally obtained, or the ion beam is collected by the Faraday cup 8 behind, then four beam spots corresponding to the four ion beams will appear on the substrate or the Faraday cup 8, and the beam spot is the cross-section of the ion beam. The beam spot is strip-shaped (strip-shaped or strip-like means a shape with a length significantly greater than the width, specifically for example an oval or a rectangle or a shape between the two), and the strip-shaped beam spots are connected in the length direction to form a basically uniform overall strip-shaped cross-section of the ion beam. The height of this overall cross-section is the required ion beam height H, and the ion beam height H is set to 1.5 m to 2.2 m according to the required process, for example.

[0042] A set of expansion coil magnets 4 on the downstream side of the first mass analysis magnet are the first expansion coil and the second expansion coil. The first expansion coil and the second expansion coil are respectively located on both sides of the ion beam flowing through the first mass analysis magnet. In other words, the ion beam flowing through the first mass analysis magnet is located between the first expansion coil and the second expansion coil. Similarly, a set of expansion coil magnets 4 on the downstream side of the second mass analysis magnet are the third expansion coil and the fourth expansion coil. The third expansion coil and the fourth expansion coil are respectively located on both sides of the ion beam flowing through the second mass analysis magnet. In other words, the ion beam flowing through the second mass analysis magnet is located between the third expansion coil and the fourth expansion coil.

[0043] The collimating coil magnet 5 is located at the beam intersection. The ion beams formed by all ion sources 1 intersect at the beam intersection in the direction of the ion beam cross-sectional width. In the embodiment, in the direction of the ion beam cross-sectional length, the ion beams are spliced in a staggered manner. The collimating coil magnet 5 is the first collimating coil and the second collimating coil. The first collimating coil and the second collimating coil are located on the outer sides of all the intersecting ion beams. In other words, the ion beam flowing through the first mass analysis magnet and the ion beam flowing through the second mass analysis magnet are both located between the first collimating coil and the second collimating coil.

[0044] More specifically, please refer to Figure 4 、 Figure 5 As shown in FIGS. [], the ion source 1, the extraction system 2, the mass analysis magnet 3, the expansion coil magnet 4, and the collimating coil magnet 5 are all arranged on the vacuum chamber. A space for the ion beam to be transmitted and travel is formed in the vacuum chamber, and this space has the vacuum degree required by the process. Among them, for the convenience of production, maintenance, etc., the vacuum chamber is composed of multiple sealed sections, and the shape of the chamber is adapted to the corresponding components such as the ion source 1, the extraction system 2, the mass analysis magnet 3, the expansion coil magnet 4, and the collimating coil magnet 5, so as to facilitate the transmission of the ion beam and the installation of each component. In the embodiment, a transition chamber 7 is also arranged between the chambers corresponding to the expansion coil magnet 4 and the collimating coil magnet 5 to match the length of the ion beam path. On the downstream side of the collimating coil magnet 5, that is, the output side of the whole ion beam system, a Faraday cup 8 is also provided to receive the ion beam. During actual process application, the substrate for ion implantation will enter between the output side of the whole ion beam system and the Faraday cup 8, so as to achieve scanning implantation.

[0045] Please refer to Figure 6, the ion source 1, extraction system 2, and mass analysis magnet 3 are arranged in a relatively compact manner. Specifically, the ion source 1 and the extraction system 2 (extraction electrode in the embodiment) are arranged in the same cavity and are hermetically connected to the middle of the mass analysis magnet 3. Preferably, a vacuum valve 6 (such as a vacuum isolation valve structure) is arranged between the extraction system 2 and the mass analysis magnet 3. The vacuum valve 6 can control the on-off between the extraction system 2 and the mass analysis magnet 3, facilitating the installation and maintenance of the front-end ion source 1 and extraction system 2, etc.

[0046] Preferably, the mass analysis magnet 3 is an even-numbered group and is arranged in mirror symmetry. For example, in the illustrated embodiment, there are two symmetrically arranged groups; correspondingly, the ion source 1, extraction system 2, expansion coil magnet 4, and collimation coil magnet 5 are also arranged in mirror symmetry. This symmetry design is beneficial to the spatial layout of the system.

[0047] It can be envisioned that the present invention is not limited to the specific illustrated embodiments. In some other embodiments, the number of ion sources in a group is one, three, or more, and / or the number of mass analysis magnets is three or more, and / or other methods are used to splice and / or coincide and / or overlap each ion beam for collection, etc. Based on the concept of the present invention, through similar or other easily conceivable designs of the ion beam path, it is possible to achieve the formation of the required ion beam by aggregating multiple ion sources.

[0048] Compared with the prior art, the beneficial technical effects of the present invention are as follows.

[0049] Due to the adoption of a multi-group ion source system, during the actual design and installation process (due to reasons such as space, mechanical structure, and the need for the final beam to converge to the same focus), the magnetic field angles at which the beam extracted from each group of ion sources enters the mass analysis magnet are different. In the prior art patent solutions as described in the background art, multiple ion sources share a group of mass analysis magnets for deflection. With a single analysis magnetic field, the beams incident at multiple angles pass through an overall deflection magnetic field, and the deflection angle is determined by the current of the magnetic coil forming the magnetic field. As a result, on the one hand, it is impossible to independently adjust the deflection angle of a beam at a certain angle, and on the other hand, due to different incident angles and positions, the deflection angles of multiple groups of beams are slightly different due to the influence of the local magnetic field.

[0050] In a typical technical solution of the present invention, a design of two sets of mass analysis magnets is adopted (hereinafter described as left and right for distinction), and the effect of beam collection is better, and the system is more stable. Specifically, the left mass analysis magnet adjusts the deflection angles of the beams extracted from the two ion sources on the left (the incident deflection angles of the beams extracted from these two ion sources in the left and right directions when entering the analysis magnetic field are the same); the ion source and the mass analysis magnet on the right are the same. In this way, the deflection angles of the left / right ion beams can be independently and finely controlled by adjusting the position and / or current of the mass analysis magnet respectively (preferably adjusting the current). The advantages of such independent adjustment include:

[0051] 1. The paths of the left / right beams can be independently fine-tuned, so that the passing performance of the left / right beams through the expansion coil and the collimation coil is better; independent adjustment cannot be achieved when one mass analysis magnet controls multiple sets of beam deflections.

[0052] 2. When the left / right beams converge at the focus of the collimation coil, the intersection angles of the left / right beams can be fine-tuned, and the beam foci of the left / right two angles can be adjusted to the same position as much as possible, so that it is easier for the collimation coil to achieve the adjustment of beam uniformity.

[0053] 3. The independent mass analysis magnet can also adjust the slight deviations that may exist in the ion source and the extraction system due to processing and installation, and can accurately adjust the beam path and other situations, so that the efficiency of the integrated beam is also higher than the existing solution using one mass analysis magnet.

[0054] In addition, for the existing solution of one set of mass analysis magnets, multiple ion sources arranged side by side need to be installed on the vacuum cavity of the same mass analysis magnet. In order to obtain the same deflection angle, the left and right ion sources need a certain installation space and incident angle, and the ion sources arranged side by side must be designed with different incident angles, and a certain installation distance also needs to be pulled apart horizontally, so a relatively large installation distance is required. In the present invention, taking the preferred two sets of mass analysis magnets as an example, due to the symmetric design of the left deflection to the left and the right deflection to the right, the installation of the ion source no longer needs to consider the space interference and angle problems between the left and right, and the connection structure and cavity design can also be simpler. Therefore, compared with the prior art, the distance between the ion source and the mass analysis magnet can be shortened, and the ion beam transmission efficiency is higher.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; for example, design and adjust the quantity, parameters, positions, etc. of each component according to the required ion beam shape, etc.; these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An ion beam system with multiple ion sources, characterized in that: It comprises at least two groups of mass analysis magnets (3); an extraction system (2) is correspondingly arranged on the upstream side of each group of mass analysis magnets (3); an ion source (1) is correspondingly arranged on the upstream side of the extraction system (2); an expansion coil magnet (4) is correspondingly arranged on the downstream side of each group of mass analysis magnets (3); and a collimation coil magnet (5) is arranged on the downstream side of the expansion coil magnet (4).

2. The ion beam system with multiple ion sources according to claim 1, characterized in that: The collimating coil magnets (5) form a group and are located at the beam intersection. The ion beams formed by all ion sources (1) intersect at the beam intersection in the direction of the ion beam cross section width.

3. The ion beam system with multiple ion sources according to claim 1, characterized in that: Different groups of mass analysis magnets (3) are independent of each other.

4. The ion beam system with multiple ion sources according to claim 1, characterized in that: The mass analysis magnets (3) are divided into two groups, namely a first mass analysis magnet and a second mass analysis magnet; and the mass analysis magnets (3) are arranged so that, for the same type of ion beam, the deflection direction of the ion beam flowing through the first mass analysis magnet is opposite to the deflection direction of the ion beam flowing through the second mass analysis magnet.

5. The ion beam system with multiple ion sources according to claim 1, characterized in that: On the upstream side of at least one group of mass analysis magnets (3), there are at least two ion sources (1), and the ion sources (1) are arranged at an angle so that at the collimating coil magnet (5), the ion beams flowing through the same mass analysis magnet are spaced apart in the cross-sectional length direction.

6. The ion beam system with multiple ion sources according to any one of claims 1 to 3, characterized in that: The mass analysis magnets (3) are in two groups, namely, a first mass analysis magnet and a second mass analysis magnet; at least two ion sources (1) are provided on the upstream side of at least one group of the mass analysis magnets (3), and the ion sources (1) are arranged at an angle so that at the collimating coil magnet (5), ion beams flowing through the same mass analysis magnet are spaced apart in the length direction of the cross section; at the collimating coil magnet (5), the ion beams flowing through the first mass analysis magnet and the ion beams flowing through the second mass analysis magnet are staggered and connected in the length direction of the cross section to form a continuous strip cross section.

7. The ion beam system with multiple ion sources according to claim 6, characterized in that: Two ion sources (1) are provided on the upstream side of the first mass analysis magnet, namely, a first ion source and a second ion source, and the output directions of the first ion source and the second ion source are close to each other on the output side and far away from each other on the input side; Two ion sources (1) are provided on the upstream side of the second mass analysis magnet, namely, a third ion source and a fourth ion source, and the output directions of the third ion source and the fourth ion source are close to each other on the output side and far away from each other on the input side; On the downstream side of the collimating coil magnet (5), the ion beam of the No. 1 ion source is spaced from the ion beam of the No. 2 ion source, and the ion beam of the No. 3 ion source is spaced from the ion beam of the No. 4 ion source; and one of the ion beams of the No. 3 ion source and the No. 4 ion source is located between the ion beam of the No. 1 ion source and the ion beam of the No. 2 ion source, and the other one of the ion beams of the No. 1 ion source and the No. 2 ion source is located outside the ion beam of the No. 1 ion source and the ion beam of the No. 2 ion source; This forms a ribbon-shaped ion beam whose cross section is a continuous strip formed by connecting four segments of ion beams.

8. The ion beam system with multiple ion sources according to any one of claims 1, 3, 4 and 5, characterized in that: A group of expansion coil magnets (4) on the downstream side of the first mass analysis magnet includes a first expansion coil and a second expansion coil, wherein the first expansion coil and the second expansion coil are respectively located on both sides of the ion beam flowing through the first mass analysis magnet; A group of expansion coil magnets (4) on the downstream side of the second mass analysis magnet are expansion coil No. 3 and expansion coil No. 4, and the expansion coil No. 3 and expansion coil No. 4 are respectively located on both sides of the ion beam flowing through the second mass analysis magnet; The collimation coil magnet (5) is located at the beam intersection, and the ion beams formed by all ion sources (1) intersect at the beam intersection in the direction of the ion beam cross-section width; the collimation coil magnet (5) includes a first collimation coil and a second collimation coil, and the first collimation coil and the second collimation coil are located on both sides of the outside of all the intersecting ion beams.

9. The ion beam system with multiple ion sources according to any one of claims 1 to 5, characterized in that: The mass analysis magnets (3) are arranged in an even array and are mirror-symmetrically arranged; the corresponding ion source (1), extraction system (2), expansion coil magnet (4), and collimation coil magnet (5) are also mirror-symmetrically arranged.

10. The ion beam system with multiple ion sources according to any one of claims 1 to 5, characterized in that: The ion source (1), the extraction system (2), the mass analysis magnet (3), the expansion coil magnet (4), and the collimation coil magnet (5) are all arranged on the vacuum chamber; and / or a vacuum valve (6) is arranged between the extraction system (2) and the mass analysis magnet (3).

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