CN221747154U - High-resolution electromagnet analyzer - Google Patents

Abstract

A high resolution electromagnet analyzer includes an arcuate yoke structure surrounding a path of travel of a ribbon ion beam, a resolving slot having a slit is disposed outwardly of an outlet end of the high resolution electromagnet analyzer for transporting the ribbon ion beam through the slit of the resolving slot to separate desired ions from contaminant ions of different momentum. The utility model enables ions to continuously go forward to the target through the high-resolution electromagnet analyzer, and can better meet the requirements of the current high-quality advanced semiconductor technology.

Description

A high-resolution electromagnet analyzer

Technical Field

The utility model belongs to the technical field of semiconductor ion implantation technology, and in particular relates to a high-resolution electromagnet analyzer.

Background Art

With the development of the semiconductor industry, the requirements for ion implantation processes have become more precise. The existing ion implantation system structure, such as the U.S. utility model patent with application publication number US5350926A (Figure 2 of this patent specification), is complex in structure and high in cost, and can only produce a ribbon ion beam with a size of 300 mm. In the system for generating ion beams, the electromagnet analyzer is one of the key components, which is required to provide good field uniformity, high resolution, light weight and other characteristics; the existing technical solutions cannot better meet the requirements of current high-quality advanced semiconductor processes.

Utility Model Content

Based on the technical problems existing in the prior art, the utility model provides a high-resolution electromagnet analyzer, which provides tight control of the edge field to provide good field uniformity through multi-faceted optimization and improvement of the system structure and method, and achieves the effects of a more compact and lightweight electromagnet structure.

According to the technical solution of the utility model, the utility model provides a high-resolution electromagnet analyzer, the high-resolution electromagnet analyzer includes a bow-shaped yoke structure surrounding the travel path of a ribbon ion beam, the bow-shaped yoke structure includes a bow-shaped wall structure, the two ends of the bow-shaped yoke structure are respectively an entrance opening end and an exit opening end of the ribbon ion beam, and the bow-shaped wall structure of the bow-shaped yoke structure encloses an internal space region used as a space channel for the ribbon ion beam; the high-resolution electromagnet analyzer also includes two annular coils that are approximately mirror-symmetrical, the two annular coils are arranged in parallel to form an aligned array, each annular coil includes a plurality of discrete coils, the two ends of the annular coil are end bending segments, and the bending directions of the two end bending segments of the same annular coil are the same; a group of a plurality of conductive segments connected in series in sequence is formed in the annular coil; the bending directions of the two end bending segments of one of the annular coils in the aligned array are opposite to the bending directions of the two end bending segments of the other annular coil;

A resolution slot with a slit is arranged outside one end of the outlet of the high-resolution electromagnetic analyzer, which is used to transmit the ribbon ion beam through the slit of the resolution slot and separate the desired ions from the pollutant ions with different momentum.

Preferably, the two annular coils in the high-resolution electromagnet analyzer are positioned within the internal space region along the inner surface of the bow-shaped magnetic yoke structure, so that the end bending sections at both ends of the annular coils extend from the two open ends of the bow-shaped magnetic yoke structure and are adjacent to the open ends respectively, and the gap space between the two annular coils serves as a limiting boundary for the travel path of the ribbon ion beam.

Furthermore, each toroidal coil includes four conductive segments connected in series, namely:

First conductive segment: a curved segment substantially parallel to the arc segment of the path of travel of the ribbon ion beam;

The second conductive segment is a curved segment that is bent by 90° relative to the first conductive segment in a direction away from the plane where the central axis of the traveling path of the ribbon ion beam is located;

The third conductive segment is a curved segment that arches across the travel path of the ion beam;

The fourth conductive segment is a bent segment bent by 90° relative to the third conductive segment in a direction close to the plane where the central axis of the traveling path of the ribbon ion beam is located.

Furthermore, each toroidal coil further comprises four conductive segments connected in series, namely:

The fifth conductive segment is a curved segment substantially parallel to the arc segment of the traveling path of the ribbon ion beam and opposite to the first conductive segment and in a direction opposite to the first conductive segment;

The sixth conductive segment is a curved segment that is bent by 90° relative to the fifth conductive segment in a direction away from the plane where the central axis of the traveling path of the ribbon ion beam is located;

The seventh conductive segment is a curved segment that arches across the travel path of the ion beam;

The eighth conductive segment is a bent segment that is bent 90° relative to the third conductive segment in the direction of the plane close to the central axis of the traveling path of the ribbon ion beam and is connected to the first conductive segment to form a ring.

Furthermore, the fifth conductive segment is behind the fourth conductive segment and connected to the fourth conductive segment.

Preferably, the average spacing of the magnetic poles of the high resolution electromagnet analyser increases along the direction of travel of the ribbon ion beam, thereby increasing the radius of the ion beam trajectory along the path of the ion beam.

Preferably, the cross-section of the arcuate yoke structure is substantially rectangular, and the cross-sectional shape can be used to limit the change of the magnetic field, thereby changing the focusing characteristics, thereby increasing the aspect ratio of the linear focus of the ribbon ion beam and/or increasing the beam flux of the ribbon ion beam passing through the slit of the resolving slot.

Preferably, the currents of the two annular coils can be adjusted to different values, thereby changing the parallelism of the ribbon ion beam with the slit of the resolving grid.

More preferably, the current difference between the two toroidal coils is no more than 20%.

Compared with the prior art, the beneficial technical effects of the utility model are as follows:

1. The high-resolution electromagnet analyzer scheme of the utility model provides a frame-shaped electromagnet having an aligned array of mirror-symmetrical paired coils, which can bend a high-aspect-ratio ribbon ion beam at an angle of not less than about 50 degrees and not more than about 100 degrees, and can perform mass analysis through a resolution slot slit at the (almost) focus of the ribbon ion beam.

2. The long transverse axis of the ion beam can exceed 50% of the bending radius to align with the generated magnetic field; the array of paired coils and their corresponding magnetic materials provide tight control of the fringe field to provide good field uniformity and can produce a more compact and lightweight structure than other electromagnet types commonly used in the ion implantation industry.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a high-resolution electromagnetic analyzer according to an embodiment of the present utility model.

FIG. 2 is a schematic diagram of the structure of an existing ion implantation system.

FIG3 is a schematic cross-sectional view of a high-resolution electromagnetic analyzer according to an embodiment of the present invention.

FIG. 4 is a schematic structural diagram of a ring coil of a high-resolution electromagnetic analyzer according to an embodiment of the present utility model.

FIG. 5 is a schematic diagram of a magnetic field of an existing electromagnet analyzer.

FIG. 6 is a schematic diagram of a magnetic field of a high-resolution electromagnet analyzer according to an embodiment of the present invention.

7 to 9 are schematic diagrams of three cross sections of a high-resolution electromagnetic analyzer along the traveling direction of an ion beam according to an embodiment of the present invention.

FIG. 10 is a partial structural perspective diagram of an ion implantation system according to an embodiment of the present invention.

FIG. 11 is a schematic diagram of a top view of the structure shown in FIG. 10 .

Description of reference numerals in the accompanying drawings:

1. High-resolution electromagnet analyzer; 101. Bow-shaped magnetic yoke structure; 102. Ion beam channel; 103. Ring coil; 104. End bend section; 105. Partition wall; 106a. First conductive section; 106b. Second conductive section; 106c. Third conductive section; 106d. Fourth conductive section; 106e. Fifth conductive section; 106f. Sixth conductive section; 106g. Seventh conductive section; 106h. Eighth conductive section; 107. Resolution slot; 2. Ion source; 3. Quadrupole linear lens; 4. Multipole lens; 501. Ion beam current density diagnostic device; 502. Injection mechanism; 503. Faraday cup; 504. Controller; B. Ribbon ion beam; W. Workpiece.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be clearly and completely described below in conjunction with the drawings in the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

It should also be noted that, for ease of description, only the parts related to the relevant utility model are shown in the drawings. In the absence of conflict, the embodiments and features in the embodiments of the utility model can be combined with each other.

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 or interdependence of the functions performed by these devices, modules or units.

It should be noted that the modifications of "one" and "plurality" mentioned in the present invention are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise clearly indicated in the context, it should be understood as "one or more".

The utility model provides a high-resolution electromagnet analyzer, which belongs to the field of semiconductor ion implantation process technology, wherein the high-resolution electromagnet analyzer includes a bow-shaped yoke structure surrounding the path of travel of a ribbon ion beam, the path of travel of the ribbon ion beam has a predetermined curve shape, the predetermined curve shape includes a circular arc segment with a radius range of 0.25 meters to 4 meters and a fixed curvature angle ranging from 50 degrees to 100 degrees; it also includes two annular coils that are approximately mirror-symmetrical (i.e., mirror-symmetrical or nearly mirror-symmetrical), the two annular coils are arranged in parallel to form an aligned array, and the two annular coils are positioned in an internal space region along the inner surface of the bow-shaped yoke structure, so that the end bending sections at both ends of the annular coils extend from the two open ends of the bow-shaped yoke structure respectively and are adjacent to the open ends. This solution can better meet the requirements of current high-quality advanced semiconductor processes by optimizing and improving the system structure and method in many aspects.

First, please refer to Figure 2. The ion implanter of the prior art uses two different magnets to produce the required ribbon ion beam. The first magnet performs mass analysis on the ion beam, and the second magnet makes the ions in the beam more parallel. Its resolution usually exceeds 80M/ΔMFWHM. This structural form is the conventional configuration of the traditional ribbon beam implantation system. However, its disadvantage is that its structure is complicated and expensive, and it can only produce a ribbon ion beam with a size of 300mm. In addition, the existing magnets used for mass analysis also have defects and shortcomings such as resolution deviation, system deviation, and limited ability to prevent beam diffusion. On the other hand, one of the main difficulties in bending the ribbon ion beam by a single magnet is that it is very likely to produce serious second-order aberrations, which will lead to distortion of the ion beam shape, which will reduce the mass resolution that can be obtained from the electromagnet analyzer, and is not conducive to the effective aspect ratio of the ion beam, and is not conducive to the efficiency and effect of scanning implantation.

Please refer to Figures 1, 3 and 4, a high-resolution electromagnet analyzer according to one embodiment of the utility model is used to separate unwanted ion species during the process of a ribbon ion beam passing through the high-resolution electromagnet analyzer. The path of the ribbon ion beam B has a predetermined curve shape, which includes a circular arc segment with a radius range of 0.25 meters to 4 meters and a fixed curvature angle ranging from 50 degrees to 100 degrees. More specifically, the two ends of the circular arc segment are straight line segments, and the angle between the two straight line segments is the curvature angle. The cross section of the ribbon ion beam B is generally rectangular or elliptical, etc., and for ease of description, the path of the center point of the cross section is called the central axis; the central axis has the above-mentioned predetermined curve shape. Under the action of the magnetic field, the ribbon ion beam B, in addition to bending, also has changes such as divergence or convergence on both sides of the central axis. The shape of the entire spatial range covered by the ribbon ion beam B during its travel is called the path of the ribbon ion beam B.

The high-resolution electromagnetic analyzer 1 includes a bow-shaped yoke structure 101 surrounding the travel path of the ribbon ion beam B. The bow-shaped yoke structure 101 is at least partially composed of ferromagnetic material. The bow-shaped yoke structure 101 includes a bow-shaped wall structure with a generally rectangular frame-shaped cross-section and a fixed size. The two ends of the bow-shaped yoke structure 101 are open ends used as the entrance and exit of the ribbon ion beam respectively. The bow-shaped wall structure of the bow-shaped yoke structure 101 encloses an internal space region of a determinable volume used as a space channel for the ribbon ion beam.

It also includes two (a pair of) annular coils 103 that are approximately mirror-symmetrical, and the two annular coils 103 are arranged in parallel to form an aligned array; more specifically, the annular coils 103 are symmetrically arranged on both sides of the plane where the central axis of the path of travel of the ribbon ion beam is located (i.e., they are arranged symmetrically from top to bottom as shown in Figures 1, 3, and 4). The two ends of the annular coil 103 are end bends 104, and the two end bends 104 of the same annular coil 103 have the same bending direction, and a group of multiple conductive segments connected in series in sequence are formed in the annular coil 103; the ribbon ion beam B travels in the internal space area of the bow-shaped magnetic yoke structure 101, and each conductive segment has a fixed pre-selected sequential position and a corresponding angular orientation relative to the path of travel of the ribbon ion beam B. Each of the toroidal coils 103 in the aligned array includes a plurality of discrete coils, which are elongated complete rings at least partially composed of conductive material; in other words, each toroidal coil 103 is composed of a plurality of discrete coils, which have end bends and other structures accordingly, so that the toroidal coil 103 becomes a multi-layer, multi-turn coil to meet the required ampere-turns. The bending direction of the two end bends 104 of one of the toroidal coils 103 in the aligned array is opposite to the bending direction of the two end bends 104 of the other toroidal coil 103. The closed-loop cavity volume in each toroidal coil 103 provides a central open space channel, which extends from one end bend 104 to the other end bend 104 in the linear dimension of the aligned array. The two toroidal coils 103 are positioned in the internal space region along the inner surfaces of the two opposing arcuate wall structures of the arcuate yoke structure 101, so that the end bends 104 at both ends of a pair of aligned toroidal coils 103 extend from the two open ends of the arcuate yoke structure 101 and are adjacent to the open ends. When the continuous ribbon ion beam B travels in the gap space existing between the two annular coils 103 located in the inner space region of the arcuate yoke structure 101, the gap space between the two annular coils 103 serves as a limiting boundary of the travel path of the continuous ribbon ion beam B. Further, the inner space region of the arcuate yoke structure 101 is bounded by the annular coils 103 at both ends in the direction of its longer dimension, and is bounded by the wall surfaces of the two arcuate wall structures of the arcuate yoke structure 101 in the direction of its shorter dimension.

In a preferred embodiment, two partition walls 105 are further provided inside the bow-shaped magnetic yoke structure 101. The two partition walls 105 and two opposite non-arc-shaped walls (the upper and lower walls in FIG. 1 and FIG. 3) of the bow-shaped magnetic yoke structure 101 are sealed and separated to form an ion beam channel 102. The ion beam channel 102 is adapted to the travel path of the ribbon ion beam B. The partition wall 105 is made of non-magnetic materials such as aluminum or non-metal. The annular coil 103 is located between the two opposite quasi-arc-shaped walls (the two side walls in FIG. 1 and FIG. 3) of the bow-shaped magnetic yoke structure 101 and the partition wall 105. This ensures that the ribbon ion beam B travels in a high vacuum environment, while the annular coil 103 and the circuit equipment connected thereto can be isolated from the high vacuum environment.

More specifically, it also includes a power supply device for providing an adjustable current to each annular coil 103 in the aligned array, the current circulates in the same direction for each annular coil 103, thereby generating a desired magnetic field, which has good field uniformity and well-contained fringe fields, and is capable of bending a high-aspect ratio ribbon ion beam B at an angle of at least 50 degrees, and can focus the ribbon ion beam B so that desired ion components pass through the resolution slot 107, while undesired ion components are not transmitted, thereby achieving mass analysis, and such an aligned array can achieve a lighter device structure compared to existing magnets.

Further, as shown in FIG4 , each annular coil 103 includes eight conductive segments connected in series, namely:

The first conductive segment 106 a is a curved segment substantially parallel to the arc segment of the traveling path of the ribbon ion beam;

The second conductive segment 106 b is a curved segment that is bent by 90° relative to the first conductive segment in a direction away from the plane where the central axis of the traveling path of the ribbon ion beam is located;

The third conductive segment 106c is a curved segment that arches across the travel path of the ion beam, and the middle part of the segment is preferably straight;

The fourth conductive segment 106d is a curved segment that is bent by 90° relative to the third conductive segment in a direction close to the plane where the central axis of the traveling path of the ribbon ion beam is located, and is substantially parallel to the second conductive segment;

The fifth conductive segment 106e is a curved segment substantially parallel to the arc segment of the traveling path of the ribbon ion beam and opposite to the first conductive segment (substantially parallel and equidistant) and in a direction opposite to the first conductive segment;

The sixth conductive segment 106f is a bent segment that is bent by 90° relative to the fifth conductive segment in a direction away from the plane where the central axis of the traveling path of the ribbon ion beam is located;

The seventh conductive segment 106g is a curved segment that arches across the travel path of the ion beam, and the middle part of the segment is preferably straight;

The eighth conductive segment 106h is a curved segment that is bent 90° relative to the third conductive segment in the direction of the plane where the central axis of the traveling path of the ribbon ion beam is located, is basically parallel to the sixth conductive segment, and has its end connected to the starting point of the first conductive segment to form a ring.

The direction of the current in each toroidal coil 103 is to circulate in the eight conductive segments in this order, thereby forming the required magnetic field. The current flowing in the two end curved segments 104 of each coil configuration extends out from the midplane of the arcuate yoke structure 101, controlling the magnetic potential distribution, thereby producing a smooth and rapid decline in the fringe field, and limiting the magnetic field to the area occupied by the ion beam. The total number of ampere-turns required for the toroidal coil 103 (and all its discrete coils) is determined by the magnetic gap, the radius of the ion deflection path, and the mass and energy of the ions. The magnetic field generated inside the closed space area (rectangular cross section) can be highly uniform until the limiting boundary imposed by the arcuate yoke structure 101 and the two toroidal coils 103. In addition, the boundary provided by a pair of toroidal coils allows a uniform field tangential to the boundary to exist in the desired direction, thereby using the entire bounded area inside the arcuate yoke structure 101 for the magnetic field. The arcuate yoke structure 101 and the toroidal coil 103 together substantially prevent the generation of an outer edge field, and the limited edge field coming out of the open end of the arcuate yoke structure 101 is attenuated and limited. At the boundary of the arcuate yoke structure 101, the magnetic field is perpendicular to the surface, so the direction of the magnetic field is determined when the steel structure of the arcuate yoke structure 101 defines a rectangular gap space and a channel at the top and bottom ends. For the boundary conditions at the edge of the coil conductor, the Maxwell curl equation can be locally simplified to The equation is obtained, and the effective solution is the constant field _By in the conductor boundary region, and By in the _conductor linearly decreases to zero as a function of x (here the ion beam is defined to travel in the z direction, the magnetic field direction is in the y direction, and the x direction is orthogonal to both the y and z directions). The present solution has a dipole field inside the bow-shaped yoke structure 101, while the extended external magnetic field does not behave as a dipole relative to the accompanying fringe field. In addition, the present solution structure can significantly reduce the amount of steel required on the side of the yoke structure, which is achieved by eliminating the fringe field in the area outside the ion beam entry and exit paths, thereby making the structure lighter and using less material. As shown in Figures 5 and 6, compared with the existing structure, the magnetic field outside the bow-shaped yoke structure 101 can be basically ignored in the present solution, achieving effective elimination of the fringe field.

The power supply device is capable of generating a substantially uniform magnetic field in the inner space region (ion beam channel 102) of the arcuate yoke structure 101, and effectively bending the ribbon ion beam B when the ribbon ion beam passes through the inner space region. More specifically, the high-resolution electromagnet analyzer is capable of effectively deflecting desired ions in the ribbon ion beam by a preselected curvature angle ranging from 50 degrees to 100 degrees, and focusing the deflected ribbon ion beam to form a line focus having an aspect ratio of at least 10.

Please refer to Figures 10 and 11. A resolution slot 107 with a slit is provided outside one end of the outlet of the high-resolution electromagnetic analyzer 1. The ribbon ion beam B is transmitted through the slit of the resolution slot 107, thereby separating the desired ions from the pollutant ions with different momentum. More specifically, the high-resolution electromagnetic analyzer 1 separates the unwanted ion species from the divergent ribbon ion beam by bending the ribbon ion beam at an angle greater than 50 degrees. More specifically, at the line focus, the ion beam can pass through the slit, which can block the unwanted fine beam in the normal mode of the mass analysis system; if the width of the ion beam focus is smaller than the width of the slit, the resolution is the ratio of the mass dispersion to the slit width; the achievable resolution is determined by the mass of the focus.

Referring to Figures 7 to 9, in a preferred embodiment, the average spacing of the magnetic poles of the high-resolution electromagnet analyzer 1 (i.e., the spacing between the middle portions of the two opposite non-arc-shaped walls of the arcuate yoke structure 101, i.e., the lengthwise dimension of the ion beam channel 102) increases along the traveling direction of the ribbon ion beam B, thereby increasing the radius of the ion beam track along the path of the ion beam. Furthermore, the shape of the magnetic poles (in other words, the shape of the ion beam channel 102) is similar to the shape of the ribbon ion beam B, and the cross-section of the ribbon ion beam B changes along its expected traveling path.

In some embodiments, the cross section of the arcuate yoke structure 101 is generally rectangular, and the cross-sectional shape can be used to limit the change of the magnetic field. In other words, the magnetic field can be adjusted by shaping the cross section, thereby changing the focusing characteristics, thereby increasing the aspect ratio of the linear focus of the ribbon ion beam B. In some other embodiments, the cross section of the arcuate yoke structure 101 is generally rectangular, and the cross-sectional shape can be used to limit the change of the magnetic field, thereby changing the focusing characteristics, thereby increasing the beam flow of the ribbon ion beam B passing through the slit of the resolution slot 107. For example, in order to maintain good focusing quality, it is necessary to control the aberration, and thus it may be necessary to slightly reshape the field distribution. The magnetic field can be made uneven by making the cross-sectional shape of the arcuate yoke structure 101 deviate from a simple rectangular shape (such as adjusting the pole pieces or the open ends at the top and bottom of the arcuate yoke structure 101), and the placement of the coil is modified to adjust the current distribution, so that a more ideal control of aberrations can be achieved.

In a preferred embodiment, the currents of the two annular coils 103 can be adjusted to different values, thereby changing the parallelism between the ribbon ion beam B and the slit of the resolution slot. More specifically, the current difference value of the two annular coils 103 is no more than 20%, and the current difference value is the ratio of the current difference of the two annular coils 103 to the smaller value of the current of the two annular coils 103.

Referring to FIG. 10 and FIG. 11 , based on the high-resolution electromagnet analyzer 1 of the utility model, the utility model provides an ion implantation system for implanting a workpiece with a ribbon ion beam, which, according to some embodiments, includes:

An ion source 2 having a slot-shaped opening (or slot) for generating a ribbon ion beam diverging in both horizontal and vertical directions; an extraction electrode is provided at the output end of the slot-shaped opening (slot); preferably, for example, the required ion beam height on the injection plane is 800 mm, and in order to reduce the required height of the high-resolution electromagnet analyzer 1, the ion beam is generated by a relatively small ion source, about 100 mm high, and the ion beam diverges and expands horizontally and vertically on the path through the magnet;

a high-resolution electromagnetic analyzer 1 for separating unwanted ion species from a traveling ribbon ion beam, which focuses the ribbon ion beam B in its narrow dimension, forming a line focus;

A resolution slot 107 having a slit, through which the focused ribbon ion beam B is transmitted, and the slit blocks unwanted contaminants;

A quadrupole linear lens 3 (or a multipole lens) capable of generating a quadrupole field of the required intensity, which focuses the ribbon ion beam B by a small amount on its longer dimension, thereby making the ion beam trajectory approximately parallel (i.e., making the shape of the path of the ribbon ion beam B approximately parallel to a ribbon along its travel direction, and all ion motion directions approximately parallel); and,

The implantation mechanism 502 , such as a scanning robot, enables the workpiece W to pass through the ribbon ion beam B along the narrow dimension direction of the ribbon ion beam B at a set speed, thereby effectively implanting a required dose of ions into the workpiece W.

Furthermore, the travel path of the ribbon ion beam B has a predetermined curve shape, which includes an arc segment with a radius ranging from 0.25 meters to 4 meters and a fixed curvature angle ranging from 50 degrees to 100 degrees; the high-resolution electromagnet analyzer includes a bow-shaped magnetic yoke structure 101 surrounding the travel path of the ribbon ion beam, the bow-shaped magnetic yoke structure 101 includes a bow-shaped wall structure, and both ends of the bow-shaped magnetic yoke structure 101 are open ends used as an entrance and an exit of the ribbon ion beam, respectively, and the bow-shaped wall structure of the bow-shaped magnetic yoke structure 101 encloses an internal space region used as a space channel for the ribbon ion beam.

Preferably, it also includes a multipole lens 4 (optionally, for example, a quadrupole lens) whose magnetic field gradient can be adjusted to control the uniformity of the ribbon ion beam, and the multipole lens 4 is located between the quadrupole linear lens 3 and the resolution slot 107. Preferably, it also includes an ion beam current density diagnostic device 501, which is used to determine the beam current density, angle and beam position of the ribbon ion beam B injected into the workpiece. The ion beam current density diagnostic device 501 can be optionally set at the same position as the workpiece W when the workpiece W is injected. The ion beam current density diagnostic device 501 is connected to a driving structure, which cooperates with the injection mechanism 502 to switch the part receiving the ribbon ion beam B to the workpiece W or the ion beam current density diagnostic device 501.

Furthermore, the ion implantation device is provided with a Faraday cup 503 on the side of the implantation mechanism 502 opposite to the resolution slot 107. The ion beam current density diagnostic device 501, the quadrupole linear lens 3, the multipole lens 4, etc. are connected to a controller 504 to adjust and control the magnetic field and the working process. It should be noted that some vacuum chamber structures are omitted in Figures 10 and 11, and the ion beam transmission and implantation processes are all carried out in a vacuum environment. The implantation mechanism 502 is located in a vacuum process chamber, and the vacuum process chamber is also connected to a vacuum transfer chamber, in which a transfer robot is provided, and the vacuum transfer chamber is also connected to two loading and locking modules.

In one mode of operation, the ion beam is a ribbon beam whose main (length) dimension exceeds the size of the workpiece W (e.g., a wafer). Therefore, the quadrupole linear lens 3 and the multipole lens 4 expand the ion beam until it reaches a size greater than the workpiece W. The current in the coil of the multipole lens 4 is controlled based on the diagnostic result of the ion beam current density diagnostic device 501 to control the current density in the ion beam profile. In particular, the current is used to collimate the ion beam so that when the ion beam is directed onto the workpiece W, the ions in the ion beam are substantially parallel. The workpiece W is translated through the ion beam along a single path once or multiple times to achieve the desired uniform dose of ions implanted into the workpiece W surface.

In the dispersion direction, the magnets in the system of this scheme focus the ion beam to the middle waist, so that a very high aspect ratio of more than 40 can be obtained in the plane downstream of the ion beam magnet, and a high resolution of 60 or more can be achieved.

In summary, the utility model provides a frame-shaped electromagnet with an aligned array of mirror-symmetrical paired coils, which can bend a high aspect ratio ribbon ion beam at an angle of not less than about 50 degrees and not more than about 100 degrees, and can be mass analyzed by a resolution slot at the (almost) focus of the ribbon ion beam. The long transverse axis of the ion beam can exceed 50% of the bending radius and align with the generated magnetic field. The array of paired coils and its corresponding magnetic material provide tight control of the fringe field to provide good field uniformity, and can produce a structure that is more compact and lightweight than other electromagnet types conventionally used in the ion implantation industry. In the system of the utility model, the ribbon beam is refocused with low aberration to obtain high resolution, which is of great value in ion implanters. After expansion and analysis, the system size is further reduced by using a small ion source and a quadrupole magnetic lens to collimate the ion beam. There is no basic restriction on the aspect ratio of the ion beam that can be analyzed. The ion implantation system based on this electromagnet as the core module includes a small ion source, an ion beam extraction electrode that gradually expands almost parallel to the direction of the electromagnet magnetic field, and the ion beam continues to expand in this magnet so that the long axis of the ion beam reaches the target length. The ion beam expansion angle is less than 10 degrees. The expanded ion beam is collimated by the quadrupole magnetic lens magnet, and the collimated ion beam continues to move toward the target through the resolution slot at an almost focused position. This solution can better meet the requirements of current high-quality advanced semiconductor processes through multi-faceted optimization and improvement of system structure and methods.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims (9)

1. A high resolution electromagnet analyzer comprising an arcuate yoke structure surrounding a path of travel of a ribbon ion beam, the arcuate yoke structure comprising an arcuate wall structure, the arcuate yoke structure having an entrance open end and an exit open end for the ribbon ion beam at each end, the arcuate wall structure of the arcuate yoke structure enclosing an interior space region for a space passage for the ribbon ion beam;

The high-resolution electromagnet analyzer also comprises two annular coils which are approximately mirror symmetry, wherein the two annular coils are arranged in parallel to form an aligned array, each annular coil comprises a plurality of discrete coils, two ends of each annular coil are end bending sections, and the bending directions of the two end bending sections of the same annular coil are the same; a group of a plurality of conductive sections which are serially connected in sequence are formed in the annular coil; the bending direction of the two end bending sections of one annular coil in the aligned array is opposite to the bending direction of the two end bending sections of the other annular coil;

A resolving slot with a slit is arranged outside one end of the outlet of the high-resolution electromagnet analyzer, and is used for transmitting the ribbon ion beam through the slit of the resolving slot and separating the needed ions from contaminant ions with different motion.

2. The high resolution electromagnet analyzer of claim 1, wherein the two toroidal coils are positioned within the interior space region along the interior surface of the arcuate yoke structure such that end bend sections at both ends of the toroidal coils extend from and adjacent to the two open ends of the arcuate yoke structure, respectively, and a gap space between the two toroidal coils serves as a limiting boundary for the path of travel of the ribbon ion beam.

3. The high resolution electromagnet analyzer of claim 2, wherein each annular coil comprises four conductive segments serially connected in sequence, respectively:

A first conductive segment: a curved section substantially parallel to the circular arc section of the travel path of the ribbon ion beam;

A second conductive segment: a curved section curved by 90 ° with respect to the first conductive section in a direction away from a plane in which a central axis of a traveling path of the ribbon ion beam is located;

Third conductive segment: a curved segment that arches across the path of travel of the ion beam;

Fourth conductive segment: the curved section is curved by 90 ° with respect to the third conductive section in a direction approaching a plane in which a central axis of a traveling path of the ribbon ion beam is located.

4. A high resolution electromagnet analyzer according to claim 3 wherein each toroidal coil further comprises four conductive segments serially connected in series, respectively:

Fifth conductive segment: a curved section substantially parallel to the circular arc section of the travel path of the ribbon ion beam and opposite to the first conductive section, the curved section having an opposite orientation to the first conductive section;

Sixth conductive segment: a curved section curved by 90 ° with respect to the fifth conductive section in a direction away from a plane in which a central axis of a traveling path of the ribbon ion beam is located;

seventh conductive segment: a curved segment that arches across the path of travel of the ion beam;

Eighth conductive segment: a curved section curved by 90 ° with respect to the third conductive section in a direction approaching a plane in which a central axis of a traveling path of the ribbon-shaped ion beam is located, and is connected to the first conductive section to form a ring shape.

5. The high resolution electromagnet analyzer of claim 4, wherein the fifth conductive segment follows and is connected to the fourth conductive segment.

6. The high resolution electromagnet analyzer of claim 1 wherein the average spacing of the poles of the high resolution electromagnet analyzer increases in the direction of travel of the ribbon ion beam such that the radius of the ion beam trajectory increases along the path of the ion beam.

7. The high resolution electromagnet analyzer of claim 1, wherein the arcuate yoke structure is generally rectangular in cross-section and the cross-sectional shape is operable to define a change in magnetic field to change the focusing characteristics, thereby increasing the aspect ratio of the line focus of the ribbon ion beam and/or increasing the beam flux of the ribbon ion beam through the slit of the resolving slot.

8. The high resolution electromagnet analyzer of claim 1, wherein the currents of the two toroidal coils can be adjusted to different values, thereby changing the parallelism of the ribbon beam with the slit of the resolving slot.

9. The high resolution electromagnet analyzer of claim 7, wherein the difference in current between the two toroidal coils is no greater than 20%.