JP4305489B2 - Ion implanter - Google Patents

Description

  The present invention relates to an ion implantation apparatus in which a ribbon-like ion beam is subjected to momentum analysis (for example, mass spectrometry) through an analysis electromagnet and then incident on a substrate to perform ion implantation on the substrate.

  In order to perform ion implantation with a high throughput on a large substrate, an ion beam in a ribbon shape (this may be referred to as a sheet shape or a belt shape, the same applies hereinafter) may be used.

  An example of an ion implantation apparatus in which a ribbon-like ion beam is subjected to momentum analysis (for example, mass spectrometry; the same applies hereinafter) through an analysis electromagnet and then incident on the substrate to perform ion implantation on the substrate is described in Patent Document 1, for example. Has been.

  An example of an analysis electromagnet intended for momentum analysis of a ribbon-like ion beam is described in Patent Document 2, for example.

  A conventional analysis electromagnet described in Patent Document 2 will be described with reference to FIG. In this figure, the yoke 36 is indicated by a two-dot chain line for easy understanding of the shapes of the coils 12 and 18. Assuming that the traveling direction of the ion beam 2 is the Z direction and the two directions substantially orthogonal to each other in the plane substantially orthogonal to the Z direction are the X direction and the Y direction, the analyzing electromagnet 40 has the Y direction. A long, vertically long ribbon-like ion beam 2 enters from the entrance 24 and exits from the exit 26.

  The analysis electromagnet 40 has a configuration in which two upper and lower coils 12 and 18 as described in FIG. 1 of Patent Document 2 and a yoke 36 corresponding to the yoke described in FIG. 21 of the same document are combined. is doing.

  The coil 12 is a saddle-shaped coil (referred to as a banana-shaped coil in Patent Document 2), and a pair of main body portions facing each other across the path (beam path) of the ion beam 2 (Patent Document 2). Is called a coil main part) 14 and a pair of crossover parts that are connected by jumping up diagonally between the ends of the main body part 14 in the direction along the Z direction so as to avoid the beam path (see FIG. (Referred to as an end flip-up portion in Patent Document 2) 16. The reason why the crossing portion 16 is slanted up at the entrance 24 and the exit 26 is to secure a beam passage region so that the ion beam 2 does not hit it.

  The coil 18 is also a bowl-shaped coil having the same structure as that of the coil 12 (however, the coil 12 is substantially plane-symmetrical with the coil 12), and a set of main body portions 20 and a set of crossover portions. 22.

  Each of the coils 12 and 18 is a multi-turn coil in which a conductor (covered conductor) whose periphery is covered with an insulating material is wound many times, and the planar shape of the coil is a fan shape. It is manufactured by a method in which bending portions are formed in the vicinity of both end portions to form the transition portions 16 and 22. As the conductor, a hollow conductor (hollow conductor) in which a coolant (for example, cooling water) flows is usually used. In this specification, “insulation” means electrical insulation.

  A yoke 36 collectively surrounds the outer sides of the main body portions 14 and 20 of the coils 12 and 18.

JP 2005-327713 A (paragraph 0010, FIGS. 1 to 4) JP 2004-152557 A (paragraphs 0006, 0022, FIG. 1, FIG. 21)

  The analysis electromagnet 40 has the following problems.

(1) at the inlet 24 and outlet 26, a large projection distances L ₁ in the directions of beam incidence and emission of the connecting portions 16, 22 from the yoke 36. This is mainly due to the following reason.

(A) In order to deflect the ribbon-shaped ion beam 2 that is long in the Y direction as uniformly as possible, the main body portions 14 and 20 of the coils 12 and 18 are elongated vertically by increasing the dimension a in the Y direction. However, since the coils 12 and 18 are formed by bending the fan-shaped coils as described above to form the crossing portions 16 and 22, respectively. the dimension a is substantially directly reflected to the distance L ₁ overhang. Therefore, the overhang distance L ₁ increases as the dimension a increases.

(B) Since the coils 12 and 18 are formed by bending the fan-shaped coil as described above to form the crossing portions 16 and 22, the main body portions 14 and 20 are restricted due to bending limitations. It is unavoidable that relatively large bent portions 30 and 32 are formed near the boundary between the crossover portions 16 and 22, and the end portions of the yoke 36 and the crossover portions are equivalent to the presence of the bent portions 30 and 32. distance L ₂ is increased between the end of 16 and 22, this distance L ₂ is for inclusion in the projection distance L _1, increases the projection distance L _1. As the dimension a is increased, the curvature radii of the bent portions 30 and 32 have to be increased due to restrictions on the bending process, and the distance L _{2 and the} overhang distance L ₁ become larger.

That is, the overhang distance L ₁ can be expressed by the following equation.

[Equation 1]
L ₁ = a + L ₂

(C) Since the crossing portions 16 and 22 are slanted up, this also causes the overhang distance L ₁ to be increased.

As described above, when the overhanging distance L _{1 of the connecting} portions 16 and 22 from the yoke 36 is large, the analysis electromagnet 40 is increased in size, and the area required for the installation of the analysis electromagnet 40 is increased. It becomes large and the area required for its installation also increases. The weight of the analysis electromagnet 40 is also increased. In addition, the magnetic field generated by the crossing portions 16 and 22 outside the yoke 36 (sometimes called a fringe field) also increases the possibility of disturbing the form (shape and posture; the same applies hereinafter) of the ion beam 2.

  (2) Power consumption in the coils 12 and 18 is large. This is mainly due to the following reason.

(A) Although the crossover portions 16 and 22 do not generate a magnetic field for deflecting the ion beam 2, the overhang distance L ₁ of the crossover portions 16 and 22 is large as described above. The length becomes longer and the wasteful power consumption in the crossing portions 16 and 22 is large, which increases the power consumption in the coils 12 and 18.

    (B) Since the coils 12 and 18 are multi-turn coils of a coated conductor as described above, it is difficult to take a large proportion of the conductor area (that is, the space factor of the conductor) in the cross section of the coils 12 and 18. As a result, power loss increases and power consumption increases. When the covered conductor is a hollow conductor, the space factor of the conductor is smaller and the power loss is larger, so that the power consumption is larger.

  When the power consumption in the coils 12 and 18 is large as described above, the power consumption of the analysis electromagnet 40 is large, and consequently the power consumption of the ion implantation apparatus is also large.

  Therefore, the main object of the present invention is to reduce the overhang distance of the coil transition portion, thereby enabling downsizing and low power consumption of the analysis electromagnet, and consequently enabling downsizing and low power consumption of the ion implantation apparatus. It is said.

One of the ion implantation apparatuses according to the present invention is
(A) If the traveling direction of the ion beam is the Z direction, and two directions substantially orthogonal to each other in a plane substantially orthogonal to the Z direction are the X direction and the Y direction, the direction of the Y direction is larger than the dimension of the X direction. An ion implantation apparatus that transports a ribbon-shaped ion beam having a large size and irradiates it with a substrate to perform ion implantation,
An ion source for generating the ribbon-like ion beam having a dimension in the Y direction larger than a dimension in the Y direction of the substrate;
Analyzing the momentum by bending the ion beam from the ion source in the X direction; and an analyzing electromagnet for forming a focal point of the ion beam having a desired momentum on the downstream side;
An analysis slit that is provided near the focal point of the ion beam from the analysis electromagnet, and performs momentum analysis of the ion beam in cooperation with the analysis electromagnet;
Correction that is provided between at least one of the ion source and the analysis electromagnet and between the analysis electromagnet and the analysis slit, and adjusts the position of the focal point of the ion beam to the position of the analysis slit by an electrostatic field. A focus correction lens that performs
An accelerator / decelerator that bends the ion beam that has passed through the analysis slit in the X direction by an electrostatic field and accelerates or decelerates the ion beam by the electrostatic field;
A substrate driving device that moves the substrate in a direction intersecting the main surface of the ion beam at an implantation position where the ion beam that has passed through the accelerator is incident on the substrate ;
An inlet electrode provided between the analysis electromagnet and the accelerometer, which bends the ion beam in the Y direction by an electrostatic field and is arranged with a gap in the ion beam traveling direction; A trajectory control lens having an electrode and an exit electrode ,
(B) The analysis electromagnet
A pair of main body portions that are opposed to each other in the X direction across the beam path that is the path of the ion beam and that cover approximately half or more of one side of the Y direction of the ion beam, and along the Z direction of both main body portions A saddle-shaped coil having a pair of crossing portions that are connected between end portions in the direction so as to avoid the beam path, and bends the ion beam in the X direction in cooperation with the second coil. A first coil for generating a magnetic field;
A pair of main body portions that are opposed to each other in the X direction across the beam path and cover approximately half or more of the other side of the ion beam in the Y direction, and between the end portions in the direction along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that are connected to each other while avoiding the beam path, and is disposed so as to overlap with the first coil in the Y direction, and cooperates with the first coil. A second coil that acts to generate a magnetic field that bends the ion beam in the X direction;
A yoke that collectively surrounds the outside of the main body of the first coil and the second coil,
(C) The upper yoke constituting the yoke is made removable.
( D ) and the first coil and the second coil of the analyzing electromagnet are each wound a plurality of times by laminating an insulating sheet and a conductor sheet each having a principal surface along the Y direction on the outer peripheral surface of the laminated insulator. laminating Te, more fan-shaped cylindrical stacked coil forming a laminated insulator on the outer peripheral surface thereof has a structure in which a cutout portion while leaving the body portion and connecting portions,
(E) A pair of the entrance electrode, the intermediate electrode, and the exit electrode of the trajectory control lens, which are arranged opposite to each other in the X direction across a gap through which the ion beam passes and are electrically connected to each other. Electrode
(F) The intermediate electrode of the trajectory control lens has convex surfaces curved in the Y direction on the upstream and downstream surfaces in the ion beam traveling direction,
(G) The entrance electrode and the exit electrode of the trajectory control lens each have a concave surface along the convex surface on a surface facing the convex surface of the intermediate electrode,
(H) The entrance electrode and the exit electrode of the trajectory control lens are kept at the same potential, and the intermediate electrode has a potential different from that of the entrance electrode and the exit electrode. It is characterized in that it is kept at a potential that makes the orbital state in the direction desired .

  In the analysis electromagnet constituting the ion implantation apparatus, the coil has a configuration in which the cutout portion is provided in the fan-shaped cylindrical laminated coil as described above, leaving the main body portion and the crossover portion. Is in a state extending substantially in parallel with the Y direction from the end of the main body. Therefore, even when the dimension of the main body part in the Y direction is increased, the dimension of the transition part in the Y direction of the beam does not increase because the dimension of the transition part in the Y direction is increased correspondingly. With such a structure, it is possible to reduce the overhang distance in the beam entering / exiting direction from the yoke of the connecting portion of the coil.

  In addition, since the overhang distance of the transition part of the coil can be reduced, the length of the transition part can also be shortened, so that useless power consumption in the transition part can be reduced. In addition, the coil has a structure in which conductor sheets are laminated with an insulating sheet interposed therebetween, so that the space factor of the conductor is higher than that of a multi-turn coil in which the coated conductor is wound many times, and the power loss is much less. Few. Therefore, power consumption can be reduced.

  As a result, it is possible to reduce the size and power consumption of the analysis electromagnet, and thus to reduce the size and power consumption of the ion implantation apparatus.

The intermediate electrode of the trajectory control lens has concave surfaces curved in the Y direction on the upstream and downstream surfaces in the ion beam traveling direction, and the entrance electrode and the exit electrode of the trajectory control lens are The surface facing the concave surface of the intermediate electrode has a convex surface along the concave surface, respectively, and the entrance electrode and the exit electrode of the trajectory control lens are kept at the same potential, and the intermediate electrode is the entrance electrode and A configuration may be adopted in which the potential is different from that of the exit electrode and is maintained at a potential that makes the trajectory state of the ion beam derived from the trajectory control lens in the Y direction desired.

The analysis electromagnet
A pair of main body portions that are opposed to each other in the X direction across the beam path that is the path of the ion beam and that cover approximately half or more of one side of the Y direction of the ion beam, and along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that connect the end portions in the direction avoiding the beam path, and in cooperation with the second inner coil, the ion beam is moved in the X direction. A first inner coil that generates a main magnetic field to be bent;
A pair of main body portions that are opposed to each other in the X direction across the beam path and cover approximately half or more of the other side of the ion beam in the Y direction, and between the end portions in the direction along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that are connected to each other while avoiding the beam path, and is arranged so as to overlap with the first inner coil in the Y direction. In cooperation with the second inner coil for generating a main magnetic field that bends the ion beam in the X direction;
A pair of main body portions outside the first inner coil and facing each other in the X direction across the beam path and the ends of the two main body portions in the direction along the Z direction are connected to each other while avoiding the beam path. One or more first outer coils for generating a sub-magnetic field for assisting or correcting the main magnetic field, wherein the coil is a saddle-shaped coil having a pair of crossing portions
A pair of main body portions outside the second inner coil and facing each other in the X direction across the beam path, and the ends of the two main body portions in the direction along the Z direction are connected to each other while avoiding the beam path. A saddle-shaped coil having a pair of crossing portions that are arranged to overlap the first outer coil in the Y direction and generate a sub-magnetic field for assisting or correcting the main magnetic field One or more second outer coils;
A yoke that collectively surrounds the outside of the main body of the first inner coil, the second inner coil, the first outer coil, and the second outer coil;
In addition, the first inner coil and the first outer coil are laminated on the outer peripheral surface of the laminated insulator by winding a plurality of layers in which an insulating sheet and a conductor sheet whose main surfaces are along the Y direction are overlapped with each other. A laminated insulator is formed on the outer circumferential surface of the laminated insulating sheet and a conductor sheet whose main surface is along the Y direction. The laminated sheet is wound by multiple turns and further laminated on the outer circumferential surface. The fan-shaped cylindrical laminated coil has a configuration in which a cutout portion is provided leaving the main body portion and the transition portion,
The second inner coil and the second outer coil are laminated on the outer peripheral surface of the laminated insulator by winding a plurality of layers of an insulating sheet and a conductor sheet whose main surface is along the Y direction. A fan in which a laminated insulator is formed, and on the outer peripheral surface thereof, an insulating sheet and a conductor sheet whose main surfaces are aligned in the Y direction are wound and laminated several times, and further, a laminated insulator is formed on the outer peripheral surface. A configuration in which a cutout portion is provided in the cylindrical tube-shaped laminated coil while leaving the main body portion and the transition portion may be used.

According to the first to fourth aspects of the present invention, each coil of the analysis electromagnet has a configuration in which a cutout portion is provided in the fan-shaped cylindrical laminated coil as described above, leaving the main body portion and the transition portion. Therefore, the crossover portion is in a state of extending substantially parallel to the Y direction from the end portion of the main body portion. Therefore, even when the dimension of the main body part in the Y direction is increased, the dimension of the transition part in the Y direction of the beam does not increase because the dimension of the transition part in the Y direction is increased correspondingly. The good Una structure of this, the connecting portions of the coils, it is possible to reduce the projection distance of directions of beam incidence and emission from the yoke.

  Therefore, the analysis electromagnet can be reduced in size, and the area necessary for installing the analysis electromagnet can be reduced. It is also possible to reduce the weight of the analysis electromagnet. In addition, the possibility that the magnetic field generated by the crossing portion of the coil disturbs the form of the ion beam is reduced.

  Moreover, since the overhang distance of the transition part of each coil can be reduced, the length of the transition part can also be shortened, so that useless power consumption in the transition part can be reduced. In addition, each coil has a structure in which conductor sheets are laminated with an insulating sheet interposed therebetween, so that the space factor of the conductor is higher than that of a multi-turn coil in which a plurality of coated conductors are wound, and the power loss is much less. Few. Therefore, power consumption can be reduced.

  As a result, it is possible to reduce the size of the ion implantation apparatus as the analysis electromagnet becomes smaller, and it is possible to reduce the area necessary for installing the ion implantation apparatus. It is also possible to reduce the weight of the ion implantation apparatus. In addition, the power consumption of the ion implantation apparatus can be reduced along with the reduction of the power consumption of the analysis electromagnet.

  Furthermore, according to invention of Claims 1-4, there exists the following effect.

  Since the ion source for generating a ribbon-like ion beam whose dimension in the Y direction is larger than the dimension in the Y direction of the substrate is provided, the substrate is larger than that in the case of using the divergence or widening of the ion beam in the Y direction. However, ion implantation can be performed at a high processing speed (throughput). This effect becomes more prominent when the substrate to be processed and thus the size of the ion beam in the Y direction are large.

  A focus correction lens that corrects the focus position of the ion beam from the analysis electromagnet to the position of the analysis slit by an electrostatic field is provided, so that the focus of the ion beam shifts from the position of the analysis slit due to the influence of space charge. Can be prevented. As a result, it is possible to compensate for the influence of space charge and to improve both the transport efficiency and resolution of the ion beam.

In the accelerator / decelerator, not only the acceleration / deceleration of the ion beam but also the ion beam can be deflected in the X direction, so that the ion beam having a desired energy can be selected and derived, and energy contamination can be suppressed. it can. In addition, since these functions can be realized with a single accelerator / decelerator, the ion beam transport path can be shortened compared with the case where an energy analyzer is provided separately, thereby improving the ion beam transport efficiency. Can be improved.
Since the trajectory control lens functions as a unipotential lens, the trajectory state in the Y direction of the ion beam can be made desired without changing the energy of the ion beam.
Moreover, since the intermediate electrode constituting the trajectory control lens has a surface curved in the Y direction as described above, and the entrance electrode and the exit electrode have surfaces along the surface, in the gaps between the electrodes, The uniformity of the electric field distribution in the Y direction becomes very good. As a result, even when the dimension in the Y direction is large, the orbital state of the ion beam in the Y direction can be made desirable with good uniformity.

According to invention of Claim 1, 2, there exists the following further effect. That is, since the analysis electromagnet includes the first coil and the second coil as described above, it becomes easy to deal with an ion beam having a large dimension in the Y direction.

According to invention of Claim 3, 4, there exists the following further effect. That is, since the analysis electromagnet includes the first outer coil and the second outer coil as described above in addition to the first inner coil and the second inner coil, it can cope with an ion beam having a large dimension in the Y direction. It becomes easy, and a magnetic field with high uniformity of magnetic flux density distribution in the Y direction can be generated in the beam path of the ion beam. As a result, the disturbance of the ion beam form at the time of extraction can be further reduced. This effect becomes more prominent when the size of the target ion beam in the Y direction is large.

  According to invention of Claim 5, there exists the following further effect. That is, by providing the magnetic poles as described above, the magnetic field is easily concentrated in the gap between the two magnetic poles, so that it is easy to generate a magnetic field having a high magnetic flux density in the beam path.

  According to invention of Claim 6, there exists the following further effect. That is, since the focus correction lens functions as a unipotential lens (in other words, an Einzel lens, the same applies hereinafter), the focus position of the ion beam can be corrected without changing the energy of the ion beam.

  According to the seventh aspect of the present invention, the following further effect is obtained. That is, in the accelerometer, the ion beam can be deflected by the portion of the second electrode configured to be divided into two electrode bodies, thereby providing the effect of energy separation. In addition, the presence of the third electrode can efficiently derive an ion beam having a specific energy, and other ions and neutral particles can be efficiently blocked by the third electrode. Energy contamination can be suppressed more effectively. In particular, it has been empirically known that neutral particles are likely to be generated by charge conversion during deceleration of ions between the first electrode and the second electrode in the deceleration mode, but many neutral particles are generated. However, since this travels straight and collides with the third electrode and is prevented, neutral particles can be effectively removed in the accelerometer.

  Further, the ion beam can be accelerated in two stages, and the ion beam can be deflected before acceleration in the latter stage of the ion beam, so that the deflection becomes easy. Furthermore, since the electrons generated by the collision of undesired ions can be bent at the second electrode to prevent the electrons from reaching the first electrode, the energy of X-rays generated by the collision of the electrons can be reduced. Can be lowered.

(1) About Ion Implantation Device FIG. 1 is a schematic plan view showing an embodiment of an ion implantation device according to the present invention. In this specification and the drawings, the traveling direction of the ion beam 50 is always the Z direction, and the two directions substantially orthogonal to each other in the plane substantially orthogonal to the Z direction are the X direction and the Y direction. For example, the X direction and the Z direction are horizontal directions, and the Y direction is a vertical direction. Note that the Y direction is a constant direction, but the X direction is not an absolute direction and changes depending on the position on the path of the ion beam 50 (see, for example, FIGS. 1 and 4). Further, in this specification, the case where ions constituting the ion beam 50 are positive ions is described as an example.

  This ion implantation apparatus is an apparatus that performs ion implantation by irradiating a substrate 60 with a ribbon-like ion beam 50, an ion source 100 that generates a ribbon-like ion beam 50, and an ion beam 50 from the ion source 100. Of the ion beam 50 having a desired momentum (focal point in the X direction; the same applies hereinafter) 56 and the analysis electromagnet 200 passing through the analysis electromagnet 200. And a substrate driving device 500 that moves the substrate 60 in a direction intersecting the main surface 52 (see FIGS. 2 and 3) of the ion beam 50 (see arrow C) at an implantation position where the ion beam 50 is incident on the substrate 60. ing.

  The path of the ion beam 50 from the ion source 100 to the substrate 60 is in a vacuum container (not shown) and is maintained in a vacuum atmosphere.

  In this specification, the “main surface” means not the end surface of a ribbon-shaped or sheet-shaped material (for example, ion beam 50, insulating sheets 266, 267, conductor sheets 268, 269, etc. described later), but the larger surface. is doing. “Downstream side” or “upstream side” means the downstream side or the upstream side when viewed in the traveling direction Z of the ion beam 50. In addition, the ion beam 50 generated from the ion source 100 and the ion beam 50 derived from the analysis electromagnet 200 are different in content, that is, the former is before momentum analysis and the latter is after momentum analysis. Since this difference is self-evident, in this specification, both are represented by the ion beam 50 without distinguishing the signs of the two.

The ion beam 50 generated from the ion source 100 and transported to the substrate 60 has, for example, a ribbon shape in which the dimension W _{Y in the} Y direction is larger than the dimension W _X in the X direction, as shown in FIG. That is, W _Y > W _X. Even if the ion beam 50 has a ribbon shape, it does not mean that the dimension W _{X in the} X direction is as thin as paper or cloth. For example, the dimension W _{X in} the X direction of the ion beam 50 is about 30 mm to 80 mm, and the dimension W _{Y in the} Y direction is about 300 mm to 500 mm, although it depends on the dimension of the substrate 60. The larger surface of the ion beam 50, that is, the surface along the YZ plane is the main surface 52.

As in the example shown in FIG. 3, the ion source 100 generates a ribbon-like ion beam 50 in which the dimension W _{Y in} the Y direction is larger than the dimension T _{Y in} the Y direction of the substrate 60. For example, if the dimension T _Y is 300 mm to 400 mm, the dimension W _Y is about 400 mm to 500 mm.

  The substrate 60 is, for example, a semiconductor substrate, a glass substrate, or another substrate. The planar shape may be a circle or a rectangle.

  In the vicinity of the focal point 56 of the ion beam 50 from the analysis electromagnet 200, a slit 70 for performing momentum analysis of the ion beam 50 in cooperation with the analysis electromagnet 200 is provided. As shown in FIG. 27, the analysis slit 70 has a slit 72 extending substantially parallel to the Y direction. The reason why the analysis slit 70 is provided near the focal point 56 of the ion beam 50 is to improve both the transport efficiency of the ion beam 50 and the resolution of the momentum analysis.

  This ion implantation apparatus further includes focus correction lenses 600 and 610 for correcting the position of the focal point 56 of the ion beam 50, orbit control lenses 700a and 700b for controlling the orbital state of the ion beam 50 in the Y direction, and deflection of the ion beam 50. And an acceleration / deceleration device 400 that performs acceleration / deceleration. These will be described in detail later.

(2) Analysis Electromagnet 200 In the following, the overall configuration of the analysis electromagnet 200, the details of the structure of each coil, the manufacturing method of each coil, the features of the analysis electromagnet 200, the control method, and other examples will be described in order.

(2-1) Overall Configuration of Analysis Electromagnet 200 An example of the analysis electromagnet 200 is shown in FIGS. 6 shows the vacuum vessel 236 removed. The analysis electromagnet 200 receives the ribbon-like ion beam 50, generates a magnetic field along the Y direction in the beam path 202 which is a path of the ion beam 50, and bends the ion beam 50 in the X direction to analyze momentum. Is to do. The magnetic field is schematically represented by magnetic lines 204 in FIG. That is, when the ion beam 50 is incident on the analysis electromagnet 200, the ion beam 50 is deflected to the right by receiving the Lorentz force F _X directed to the right as viewed in the traveling direction Z by the magnetic field while traveling, and thereby the momentum. Analysis is performed. A center trajectory 54 of the ion beam 50 is indicated by a one-dot chain line in FIG. Let the radius of curvature be R. An angle (deflection angle) for deflecting the ion beam 50 by the analysis electromagnet 200 is defined as α.

  The radius of curvature R is, for example, 300 mm to 1500 mm. The deflection angle α is, for example, 60 degrees to 90 degrees. FIG. 4 illustrates a case where the deflection angle α is 90 degrees.

  The analysis electromagnet 200 also includes a first inner coil 206, a second inner coil 212, one or more (three in this embodiment) first outer coils 218, and one or more (this implementation), also referring to FIG. The embodiment includes three second outer coils 224, a yoke 230, and a set of magnetic poles 232. The beam path 202 is surrounded by a vacuum container 236 made of a non-magnetic material and is maintained in a vacuum atmosphere. This vacuum vessel 236 is also called an analysis tube.

  Since the first inner coil 206 and the second inner coil 212 are extracted and shown in FIG. 8, it is easier to understand by referring to them.

  Each coil 206, 212, 218, 224, in this example, is substantially plane symmetric in the Y direction with respect to a symmetry plane 234 (see FIG. 5, etc.) that passes through the center in the Y direction of the beam path 202 and is parallel to the XZ plane. It has the shape of The same applies to a coil 320 (see FIGS. 22 and 24), a first coil 326, and a second coil 328 (see FIG. 25), which will be described later. Such plane symmetry makes it easy to generate a magnetic field having good symmetry in the Y direction in the beam path 202. This contributes to minimizing the disturbance of the shape of the ion beam 50 when it is emitted from the analysis electromagnet 200.

  In the following, when it is necessary to distinguish the plurality of first outer coils 218 and the plurality of second outer coils 224 from each other, as shown in FIGS. 5, 9, 13, etc. Are the first outer coils 218a, 218b, and 218c in order from the upper side in the Y direction, and the second outer coil 224 is plane-symmetric with the first outer coil 218 as described above. The second outer coils 224a, 224b, and 224c are used.

  In the drawings, the underline is attached to the reference numerals indicating the coils 206 and the like, which means that the entire coils and the like are shown.

  The first inner coils 206 are opposed to each other in the X direction across the beam path 202 with reference mainly to FIGS. 8 and 12 and one side in the Y direction of the ion beam 50 (upper side in this embodiment). A pair of main body portions 208 that cover approximately half or more (in other words, substantially more than half) of the two, and end portions in the direction along the Z direction of the two main body portions 208 (in other words, the inlet 238 side of the analyzing electromagnet 200) And an end portion on the outlet 240 side (the same applies to other coils), and a saddle type coil having a pair of connecting portions 210 that are connected to each other while avoiding the beam path 202. In cooperation with the second inner coil 212, a main magnetic field for bending the ion beam 50 in the X direction is generated. The main magnetic field refers to such a magnetic field that bends the ion beam 50 with a predetermined radius of curvature R mainly by the magnetic field.

  The reason why it is called a saddle type is that when the first inner coil 206 is viewed as a whole, it has a shape similar to a saddle. The same applies to the other coils 212, 218, 224 and coils 326, 328 described later.

  The crossing portion 210 is provided away from the beam path 202 on the upper side in the Y direction in order to prevent the ion beam 50 from hitting and to reduce the influence of the magnetic field generated there on the ion beam 50. For the same purpose, other coil transition portions are also provided apart from the beam path 202 on the upper side or the lower side in the Y direction.

  Referring mainly to FIG. 8, the second inner coils 212 are opposed to each other in the X direction across the beam path 202, and are substantially on the other side in the Y direction of the ion beam 50 (the lower side in this embodiment). A pair of main body portions 214 that cover more than half (in other words, substantially more than half) and the end portions in the direction along the Z direction of both main body portions 214 are connected to each other while avoiding the beam path 202. A saddle-shaped coil having a pair of crossing portions 216, which is disposed so as to overlap with the first inner coil 206 in the Y direction, and cooperates with the first inner coil 206 to cooperate with the ion beam 50. Generates a main magnetic field that bends in the X direction. That is, the second inner coil 212 generates a magnetic force line 204 in the same direction as the first inner coil 206.

  The second inner coil 212 has the same size and structure as the first inner coil 206. The number of windings of the conductor (specifically, the conductor sheet 268; see FIG. 10 and the like) is usually the same as that of the first inner coil 206. However, as described above, the first inner coil 206 is symmetrical with respect to the symmetry plane 234. The crossover part 216 is provided on the opposite side (that is, the lower side) of the crossing part 210 in the Y direction across the beam path 202.

  A slight gap (for example, about 20 mm) 242 is provided between the first inner coil 206 and the second inner coil 212 as shown by a line in FIG. There can be provided a total of two cooling plates 312 (see FIG. 19) to be described later, one on the first inner coil 206 side and one on the second inner coil 212 side.

  Each of the first outer coils 218 mainly includes a pair of body portions 220 that are outside the first inner coil 206 and are opposed to each other in the X direction with the beam path 202 interposed therebetween, with reference mainly to FIG. A saddle-shaped coil having a pair of connecting portions 222 that connect the end portions in the direction along the Z direction of both the main body portions 220 while avoiding the beam path 202, the main magnetic field A secondary magnetic field is generated to assist or correct the above. The first outer coils 218 are arranged so as to overlap in the Y direction.

  More specifically, the main body portion 220 of each first outer coil 218 and the lateral portion of the crossover portion 222 (portion corresponding to the lateral portion 284 shown in FIG. 12) are arranged so as to overlap each other in the Y direction. Although it may be difficult to say that the vertical portion of the crossover portion 222 (the portion corresponding to the vertical portion 282 shown in FIG. 12) is arranged as described above when viewed strictly, It can be said that the first outer coils 218 are arranged so as to overlap each other in the Y direction. The same applies to each second outer coil 224.

  Each first outer coil 218 has substantially the same structure as the first inner coil 206. However, the dimension in the Y direction is smaller than that of the first inner coil 206. Also, the number of windings of the conductor is usually smaller than that of the first inner coil 206. Each first outer coil 218 has the same number of turns of the conductor (specifically, the conductor sheet 269; see FIG. 10 and the like). The dimensions of the first outer coils 218 in the Y direction are different in this embodiment, but may be the same. The same applies to each second outer coil 224.

  For example, the dimensions in the Y direction of the main body portion and the transition portion of each coil are about 230 mm for the first inner coil 206 and the second inner coil 212, about 50 mm for the first outer coil 218 a and the second outer coil 224 a, It is about 60 mm for the first outer coil 218b and the second outer coil 224b, and is about 100 mm for the first outer coil 260c and the second outer coil 224c.

  In FIG. 7, between the first outer coils 218, between the second outer coils 224, and between the lowermost first outer coil 218 (218 c) and the uppermost second outer coil 224 (224 c), Although indicated by lines, slight gaps 244, 246, and 248 are provided (see also FIG. 9). The cooling plate 312 (refer FIG. 19) mentioned later can be provided there. For example, the size of the gaps 244 and 246 is about 10 mm, and the size of the gap 248 is about 20 mm to match the gap 242. The gaps 244, 246 are provided along the entire circumference along the outer coils 218, 224.

  Each first outer coil 218 may generate a magnetic field in the same direction as the first inner coil 206 and the second inner coil 212, or may generate a magnetic field in the opposite direction, and control the direction of the magnetic field by controlling the direction of the magnetic field. It may be reversed. The same applies to each second outer coil 224. A part of the lines of magnetic force (magnetic field) generated in the main body 220 of each first outer coil 218 spreads toward the beam path 202 (in other words, leaks out), and thus affects the main magnetic field. Accordingly, each first outer coil 218 can generate a sub-magnetic field that assists or corrects the main magnetic field. In that case, each first outer coil 218 has an effect of assisting or correcting the main magnetic field mainly in the region near the inner side. The same applies to each second outer coil 224.

  Each of the second outer coils 224 mainly includes a pair of main body portions 226 that are outside the second inner coil 212 and face each other in the X direction with the beam path 202 interposed therebetween, mainly referring to FIG. A saddle type coil having a pair of crossing portions 228 connecting the end portions in the direction along the Z direction of both the main body portions 226 avoiding the beam path 202, the main magnetic field A secondary magnetic field is generated to assist or correct the above. Each second outer coil 224 is arranged so as to overlap in the Y direction. In addition, it is arranged so as to overlap with the first outer coil 218 in the Y direction.

  Each second outer coil 224 has substantially the same structure as the second inner coil 212. However, the dimension in the Y direction is smaller than that of the second inner coil 212. Also, the number of windings of the conductor is usually smaller than that of the second inner coil 212. The number of turns of the conductor (specifically, the conductor sheet) of each second outer coil 224 and the dimension in the Y direction are as described above.

  As an example of the number of turns of each conductor, the number of turns of the conductors of the first inner coil 206 and the second inner coil 212 is about 110, respectively, and the conductors of the first outer coil 218 and the second outer coil 224 are respectively. Each winding is about 85 times.

  The main body portions 208, 214, 220, and 226 of each coil are portions that are almost entirely located within the yoke 230 and generate a target magnetic field (main magnetic field or sub magnetic field) in the beam path 202. It can also be said. The same applies to a main body 322 of a coil 320 described later.

  The crossing portions 210, 216, 222, and 228 of each coil are electrically connected between ends in a direction along the Z direction of a pair of main body portions, and cooperate with the main body portion to form a loop-shaped conductive member. It can also be said that it is a part that forms a path. The same applies to transition portions 324 and 325 of a coil 320 described later.

  5 is a longitudinal sectional view taken along the line AA in FIG. 4, and FIG. 5 shows the main body portions 208, 214, 220, and 226 of the coils 206, 212, 218, and 224. . 24 to 26 described later also show the main body of each coil.

  The yoke 230 is made of a ferromagnetic material and collectively surrounds the outside of the main body portions 208, 214, 220, and 226 of the coils 206, 212, 218, and 224. Such a yoke 230 also has an effect of reducing the leakage magnetic field to the outside. The plane shape of the yoke 230 has a so-called fan shape as shown in FIG. The yoke 230 has a square frame shape (cross section along the XY plane). Such a yoke 230 may be called a window frame type yoke.

  In this embodiment, the upper yoke 231 constituting the yoke 230 is detachable. How to use the upper yoke 231 will be described later.

Each of the pair of magnetic poles 232 is made of a ferromagnetic material, and protrudes inward from the yoke 230 so as to face each other in the Y direction with the beam path 202 interposed therebetween. For example, it protrudes about 15 mm. The planar shape of each magnetic pole 232 has an arc shape along the central orbit 54 of the ion beam 50 shown in FIG. This is sometimes called a fan shape. The gap length G between the magnetic poles 232 is somewhat larger (for example, about 100 mm to 150 mm) than the dimension W _{Y in} the Y direction of the ion beam 50. Although such a magnetic pole 232 is not essential, if it is provided, the magnetic field lines 204 tend to concentrate in the gap between the magnetic poles 232, so that it is easy to generate a magnetic field having a high magnetic flux density in the beam path 202. become.

The gap length G between the magnetic poles 232 has, for example, a size that is 1/2 or more of the curvature radius R. As a specific example, when the curvature radius R is 800 mm, the gap length G is, for example, 500 mm. The gap length G usually has a size equal to or larger than the width W _G of each magnetic pole 232. That is, _G ≧ W G. With such a dimensional relationship, the magnetic pole 232 and the yoke 230 need not be unnecessarily enlarged.

  5 to 7, it seems that there are gaps between the first inner coil 206 and the first outer coil 218 and between the second inner coil 212 and the second outer coil 224. However, in this embodiment, the laminated insulator 262 shown in FIGS. 9 and 10 is interposed between them.

(2-2) Structure and the like of each coil Next, the structure and the like of each coil will be described in detail. FIG. 9 is a schematic diagram showing an enlarged cross section of the first inner coil and the first outer coil along line DD in FIG. FIG. 10 is an exploded cross-sectional view of the first inner coil and the uppermost first outer coil shown in FIG.

  The first inner coil 206 and the first outer coil 218 have an insulating sheet 266 whose main surface 266a extends along the Y direction and a conductor sheet 268 whose main surface 268a extends along the Y direction on the outer peripheral surface of the first laminated insulator 261. The superposed one (set 264) is wound and laminated several times (stacked in the direction of arrow 270 crossing the Y direction, the same applies hereinafter), and a second laminated insulator 262 is formed on the outer peripheral surface thereof. An insulating sheet 267 whose main surface 267a extends along the Y direction and a conductor sheet 269 whose main surface 269a extends along the Y direction are stacked one on top of the other (set 265), and the third stack is formed on the outside. Notch portions 272 to 275 (FIG. 7) are formed on the fan-shaped cylindrical laminated coil 290 (see FIG. 14) on which the insulator 263 is formed, leaving the main body portions 208 and 220 and the transition portions 210 and 222. Has a structure in which the irradiation).

  In order to facilitate understanding of the notches 272 to 275, the notches 272 to 275 of the first inner coil 206 are shown in FIG. The first outer coil 218 is also provided with notches 272 to 275 similar to this.

  The yoke 230 fits into the two notches 272 and 273 located in the inner and outer directions of the radius of curvature R. That is, it has a shape that matches the shape of the yoke 230. The same applies to notches 276 to 279 of the coil 320 described later. The two notches 274 and 275 on the traveling direction Z side of the ion beam 50 form the upper half of the inlet 238 and the outlet 240, respectively.

  The second laminated insulator 262 may be viewed as constituting the first inner coil 206 (shown as such in FIG. 10), and viewed as constituting the first outer coil 218. Alternatively, it may be seen that both the coils 206 and 218 are shared.

  As shown in FIG. 15, the laminated coil 290 shown in FIG. 14 includes an inner coil 292 and an outer coil 294 having the same cross-sectional structure as FIG. Also in this case, the second laminated insulator 262 may be regarded as constituting the inner coil 292 (shown as such in FIG. 15), and may be regarded as constituting the outer coil 294. Alternatively, it may be seen that both the coils 292 and 294 are shared.

  When the portions 272a to 275a of the laminated coil 290 corresponding to the notches 272 to 275 are removed by cutting or the like to form the notches 272 to 275, the inner coil 292 becomes the first inner side. The outer coil 294 becomes the first outer coil 218.

  Further, in this embodiment, in order to divide the first outer coil 218 into three (in three stages), the outer coil 294 of the laminated coil 290 is provided with the gap 244 by cutting or the like.

  The laminated insulators 261, 262, and 263 of the laminated coil 290 are formed by, for example, winding a prepreg sheet a plurality of times and laminating. A prepreg sheet 300 in FIG. 16 is the prepreg sheet. The prepreg sheet is a sheet obtained by impregnating a support having insulation properties and heat resistance with a resin having insulation properties and treating it in a semi-cured state.

  The support is made of, for example, glass fiber or carbon fiber. The resin is made of, for example, an epoxy resin or a polyimide resin. The laminated insulators 261 to 263 formed using such a prepreg sheet can also be referred to as fiber reinforced plastic (FRP). The thickness of the laminated insulators 261 to 263 may be selected according to the strength required as a structural material.

  The insulating sheets 266 and 267 are, for example, sheets made of Nomex (registered trademark), Lumirror (registered trademark) or Kapton (registered trademark), or other insulating sheets, respectively. The thickness of the insulating sheets 266 and 267 may be selected according to the required withstand voltage. For example, it is about 75 μm, but it may be thinner.

  The conductor sheets 268 and 269 are each made of, for example, a copper sheet or an aluminum sheet. These thicknesses may be selected according to the current value to be passed. For example, the thickness in the case of a copper sheet is about 0.4 mm, and the thickness in the case of an aluminum sheet is about 0.5 mm. What is necessary is just to select the width | variety of the direction corresponded to these Y directions according to the dimension of the Y direction of the coil required. For example, it is 230 mm (the width before processing described later is, for example, about 234 mm). The widths of the laminated insulators 261 to 263 and the insulating sheets 266 and 267 may be matched with this.

  Contrary to FIG. 10, the insulating sheet 266 and the conductor sheet 268 are overlapped with each other by arranging the conductor sheet 268 on the inner side of the first inner coil 206 (left side in FIG. 10, that is, the laminated insulator 261 side). The insulating sheet 266 may be placed on the outer side. If necessary, the insulating sheets 266 may be stacked on both sides of the conductor sheet 268. The same applies to the insulating sheet 267 and the conductor sheet 269 of the first outer coil 218.

When viewed in plan, the conductor sheet 268 of the first inner coil 206 has a structure in which it is wound in a fan shape a plurality of times as shown in FIG. 11, and terminals 340 are connected to both ends thereof. However, the number of windings is not limited to that shown in the figure. By passing a current I _M through the conductor sheet 268, the magnetic lines of force 204 that form the main magnetic field can be generated. FIG. 12 also shows the same current I _M and magnetic field lines 204.

  The conductor sheet 269 of the first outer coil 218 has the same structure as that shown in FIG.

  The second inner coil 212 and the second outer coil 224 also have the same structure as the first inner coil 206 and the first outer coil 218. However, as described above, the first inner coil 206 and the first outer coil 218 have a plane-symmetric shape with respect to the plane of symmetry 234.

  In addition, a member for reinforcing the coil or the like may be further provided on the outer peripheral portion of the outer laminated insulator 263 (in the case of the coil shown in FIG. 23, the laminated insulator 262) as necessary.

  An example of the structure of the transition part of each coil will be described in more detail with reference to FIG. 12 by taking the first inner coil 206 as an example.

  Each bridging portion 210 of the first inner coil 206 is connected to the end portion of the main body portion 208 in the direction along the Z direction at substantially right angles, and extends in two vertical portions 282 substantially parallel to the Y direction. And a lateral portion 284 connected to both longitudinal portions 282 substantially at right angles and extending substantially parallel to the XZ plane. That is, the vertical portions 282 are connected by the horizontal portion 284. Accordingly, the first inner coil 206 has a horizontal conductive path 286 substantially perpendicular to the Y direction and a vertical conductive path 288 substantially parallel to the Y direction. That is, except for the corners, most of the conductive paths of the first inner coil 206 are configured by combining both conductive paths 286 and 288. The current densities in the conductive paths 286 and 288 are substantially the same everywhere.

  The crossover portions 216, 222, and 228 of the other coils 212, 218, and 224 also have the same structure as that of the crossover portion 210. Accordingly, each of the other coils 212, 218, and 224 also has a horizontal conductive path that is substantially orthogonal to the Y direction and a vertical conductive path that is substantially parallel to the Y direction. That is, except for the corners, most of the conductive paths of these coils are configured by combining a horizontal conductive path and a vertical conductive path. The current densities in the horizontal conductive path and the vertical conductive path are substantially the same everywhere. The same applies to a coil 320 described later.

  It is preferable that the crossing portion of each coil has the above-described structure, and by doing so, it is possible to more reliably reduce the overhang distance of the crossing portion from the analysis electromagnet 200 in the beam entering / exiting direction. This overhang distance will be described in detail later.

An example of the power supply configuration for each coil is shown in FIG. In this example, a DC main power source 250 is connected to each of the first inner coil 206 and the second inner coil 212, and the first inner coil 206 and the second inner coil 212 are substantially connected to each other from the main power source 250. The current I _M having the same magnitude can be supplied to the two. Note that the two main power sources 250 do not necessarily need to be separate, and may be a main power source that combines them.

Further, in this example, a DC sub-power source 252 is connected to each first outer coil 218 (218a to 218c) and each second outer coil 224 (224a to 224c), and each first power source 252 is connected to each first power source 252. can the outer coil 218 and the second outer coil 224 flow the current I _S, moreover it can be controlled independently of the current I _S flowing through the respective first outer coil 218 and the second outer coil 224. Incidentally, the plurality of sub-power supply 252 is not necessarily required to be separately disposed, they are combined into one, each independently current I _S flowing through the respective first outer coil 218 and the second outer coil 224 It is also possible to use one sub-power supply that can be controlled.

(2-3) Method for Manufacturing Each Coil Next, an example of the method for manufacturing each coil will be described by taking the first inner coil 206 and the first outer coil 218 as examples.

  First, the sector-shaped cylindrical laminated coil 290 shown in FIG. 14 is manufactured. This is done as follows.

  First, as shown in FIG. 16, a mold 296 having an arcuate portion 297 projecting outward opposite to the arcuate portion 291 of the laminated coil 290 shown in FIG. As described above, the prepreg sheet 300 as described above is wound a plurality of times. Thereby, the laminated insulator 261 shown in FIGS. 15 and 17 is formed.

  Next, as shown in FIG. 17, the mold 296 is rotated in the same manner as described above so that the insulating sheet 266 and the conductor sheet 268 are overlapped with each other, and are wound around the outer peripheral surface of the laminated insulator 261 by multiple turns. To do. Thus, a laminated body of the insulating sheet 266 and the conductor sheet 268 shown in FIG. 15 is formed.

  Next, similarly to the case of FIG. 16, the prepreg sheet 300 is wound around the outer peripheral surface of the laminated body of the insulating sheet 266 and the conductor sheet 268 a plurality of times. Thereby, the laminated insulator 262 shown in FIG. 15 is formed.

  Next, as in the case of FIG. 17, the insulating sheet 267 and the conductor sheet 269 are overlapped with each other and wound around the outer peripheral surface of the laminated insulator 262 a plurality of times. Thereby, a laminated body of the insulating sheet 267 and the conductor sheet 269 shown in FIG. 15 is formed.

  Next, similarly to the case of FIG. 16, the prepreg sheet 300 is wound around the outer peripheral surface of the laminate of the insulating sheet 267 and the conductor sheet 269 a plurality of times. Thereby, the laminated insulator 263 shown in FIG. 15 is formed.

  When the mold 296 is removed after the above process, as shown in FIG. 18, the laminated coil 290a is formed of the inner coil 292 and the outer coil 294, but the arc-shaped portion 291a projects outwardly opposite to the arc-shaped portion 291. can get.

  In addition, the conductor sheet 268 can be connected to the terminal 340 (see FIG. 11) using the lead plate by sandwiching the lead plate between the winding start portion and the winding end portion of the conductor sheet 268, respectively. . The same applies to the conductor sheet 269.

  Further, before winding as described above, abrasive grains (shots) such as metal particles are sprayed on the main surfaces 268a, 269a on both the front and back sides of the conductor sheets 268, 269 (that is, shot blasting is performed) to It is preferable to keep it rough. By doing so, the surface area can be increased and the adhesion with the insulating sheets 266, 267 and the like can be improved. Although the shot blast treatment is effective even when applied to at least one main surface of the conductor sheets 268 and 269, it is preferable to apply the shot blast treatment to both main surfaces. The same applies to the insulating sheets 266 and 267.

  Similarly, it is preferable that the main surfaces 266a and 267a on both sides of the insulating sheets 266 and 267 are also subjected to shot blasting to roughen the surface. By doing so, it is possible to increase the surface area and further improve the adhesion with the conductor sheets 268, 269 and the like.

  Next, after winding a heat-shrink tape (not shown) around the outer periphery of the laminated coil 290a, the arc-shaped portion 291a is pressed (pressed) as shown by an arrow 302 as shown in FIG. The molded product to be formed is heated and cured. As a result, a laminated coil 290b that is the basis of the laminated coil 290 shown in FIG. 11 is obtained. By winding the heat shrinkable tape, the strength of the structure is improved. Instead of the heat shrinkable tape, a prepreg tape having the same configuration as that of the prepreg sheet described above may be wound.

  Next, after the laminated coil 290b is vacuum impregnated with resin, it is cured by heating under pressure. In short, this is to perform resin molding. Thereby, the laminated coil 290 shown in FIG. 14 is obtained. By performing this resin molding, the adhesion strength between the layers of the laminated coil 290 can be increased to increase the strength of the coil, and the electrical insulation performance can be improved.

  Next, after cutting the both ends of the laminated coil 290 in the axial direction (in other words, the height direction) to make a flat surface, the portions 272a to 275a corresponding to the notches are cut, The notches 272 to 275 are formed.

  When the outer coil 294 is a plurality of the first outer coils 218, the outer coil 294 is grooved in a portion corresponding to the gap 244 to form the gap 244.

  Next, the laminated coil 290c subjected to cutting and grooving as described above is immersed in an etching solution for etching the material of the conductive sheets 268 and 269 (as described above, copper or aluminum) to perform an etching process. Thereby, burrs and the like of the conductor sheets 268 and 269 generated on the processed surface during the cutting and grooving are removed to prevent a short circuit (layer short) between the conductor sheets 268 and 269, and the insulating sheet 266, The end surfaces of the conductor sheets 268 and 269 are recessed more roundly than the end surfaces of the H.267, and the creeping distance of the interlayer insulation of the conductor sheets 268 and 269 can be increased to improve the insulation performance.

  Then, a heat shrink tape is wound around the entire laminated coil 290d subjected to the etching process as described above, and is cured by heating. As a result, a fan-shaped cylindrical laminated coil in which the first inner coil 206 and the first outer coil 218 shown in FIGS. 4 to 10 and the like are integrated can be obtained. By winding the heat shrinkable tape, the strength of the structure is improved. However, when the coil has a forced cooling structure as described below, the cooling plate 312 may be attached as follows before winding the heat shrink tape. Instead of the heat shrinkable tape, a prepreg tape having the same configuration as that of the prepreg sheet described above may be wound.

  That is, as shown in FIG. 19, the cooling plate 312 having the refrigerant passage 314 is placed on the upper and lower end surfaces 306 to 307 and the gaps 244 of the first inner coil 206 and the first outer coil 218 with the insulator 316 interposed therebetween. Install with pressure contact. The cooling plate 312 is preferably provided not only on the upper and lower end surfaces in the Y direction of the main body portions 208 and 220 of the coils 206 and 218 but also on the upper and lower end surfaces in the Y direction of the transition portions 210 and 222. That is, it is preferable to provide in as wide a region as possible. For example, cooling water flows through each refrigerant passage 314. In this example, the insulator 316 is wound around the cooling plate 312, but it is not always necessary to wind it.

  With the cooling plate 312, the coils 206 and 218 can be forcibly cooled from their end faces. Such a cooling structure is sometimes called an end cooling system.

  In the above case, a thermal diffusion compound (for example, silicone grease) having good thermal conductivity is interposed between the cooling plate 312 and the insulator 316 and between the insulator 316 and the end surfaces of the coils 206 and 218 ( For example, it is preferably applied). By doing so, it is possible to eliminate the air layer as much as possible, and to further improve the heat conduction performance and thus the cooling performance.

  Further, each of the gaps 244 is formed in a wedge shape that narrows toward the inside of the coil 218 (left side in FIG. 19), and the cooling plate 312 attached to the gap 244 is also formed in a similar wedge shape, and the cooling plate 312 is press-fitted. Also good. By doing so, the gap between the end face of the coil 218 and the cooling plate 312 can be reduced to improve the adhesion, so that the cooling performance can be further improved.

  When the cooling plate 312 is provided as described above, the heat-shrinkable tape or prepreg tape may be wound around the entire coil in the state shown in FIG. Thereby, the cooling plate 312 can be fixed and adhered.

  And finally, you may mold the whole coil including the 1st inner side coil 206 and the 1st outer side coil 218 with resin, also when the cooling plate 312 is not provided, as needed. By doing so, the moisture resistance performance, insulation performance, mechanical strength, etc. of the coil can be further improved. In that case, it is preferable to mix 5-30 weight% filler (filler) with the said resin. If it does so, the crack-proof performance etc. of resin can be improved.

  Similarly to the above, the second inner coil 212 and the second outer coil 224 can be manufactured as a combination of the coils 212 and 224. Also, the coil 320 shown in FIGS. 22 to 24, the first coil 326 and the second coil 328 shown in FIG. 25, the inner coil 330, the first outer coil 218, and the second outer coil 224 shown in FIG. It can be manufactured in the same manner as described above. The inner and outer coils can be manufactured integrally.

  The assembly of the analysis electromagnet 200 shown in FIGS. 4 and 5 using the coils 206, 218, 212, and 224 may be performed by the following procedure, for example. That is, with the upper yoke 231 of the yoke 230 removed, the yoke 230 is first integrated with the second inner coil 212 and the second outer coil 224, and then the vacuum vessel 236 is inserted from above. Then, the integrated first inner coil 206 and first outer coil 218 are inserted from above, and finally the upper yoke 231 is attached.

(2-4) Features of Analyzing Electromagnet 200 In the analyzing electromagnet 200, the first inner coil 206 and the first outer coil 218 are provided with the main body portions 208, 220 and the fan-shaped cylindrical laminated coil 290 as described above. Since the cutout portions 272 to 275 are provided with the crossover portions 210 and 222 being left, the crossover portions 210 and 222 extend substantially in parallel to the Y direction from the end portions of the main body portions 208 and 220. It is in the state. Therefore, even when the dimensions of the main body portions 208 and 220 in the Y direction are increased, the dimensions of the crossover portions 210 and 222 in the Y direction need only be increased correspondingly, so that the crossover portions 210 and 222 in the beam incident / exit direction are sufficient. The overhang distance of does not increase.

The above will be described with reference to FIG. 8 by taking the first inner coil 206 as an example. When the dimension a in the Y direction of the main body 208 is increased, the dimension c in the Y direction of the transition section 210 is correspondingly increased. Can be increased. Specifically, the dimensions a and c are substantially equal to each other. Therefore, even when the dimension a is increased, the overhanging distance L ₃ (see FIG. 4) of the transition portion 210 in the incident / exit direction of the ion beam 50 does not increase. The overhang distance L ₃ is determined by the distance L ₅ between the end face of the yoke 230 and the end face of the transition part 210 and the thickness b of the transition part 210. That is, the overhang distance L ₃ can be expressed by the following equation. Incidentally, as can be seen from the above description of the structure of the first inner coil 206, the thickness of the main body 208 is also b.

[Equation 2]
L ₃ = b + L ₅

The above formula 2 does not include the dimension a in the Y direction, unlike the above formula 1 that represents the overhang distance L ₁ of the conventional analysis electromagnet 40. This is a feature that is greatly different from the conventional analysis electromagnet 40.

Moreover, the distance L ₅ can also be made smaller than the distance L ₂ of the conventional analysis electromagnet 40. This is because the crossover part 210 is not formed by bending the crossover part 16 obliquely by bending as in the conventional coil 12, but as described above, the cutout part 272 is formed in the fan-shaped cylindrical laminated coil 290. This is because the crossing portion 210 extends substantially parallel to the Y direction. In addition, it is because the corner portion 254 at the boundary between the main body portion 208 and the crossover portion 210 can be brought into a state close to a right angle with little roundness by cutting or the like.

For the above reasons, the overhanging distance L ₃ of the transition portion 210 from the yoke 230 in the beam incident / exit direction can be reduced.

  The same applies to the second inner coil 212 and the second outer coil 224.

For example, when the dimension a in the Y direction is the same 250 mm, the protruding distance L ₁ is about 300 mm in the conventional analysis electromagnet 40, whereas the protruding distance L ₃ is only about 110 mm in the analysis electromagnet 200.

For the same reason as described above, even when the inner coils 206 and 212 and the outer coils 218 and 224 are doubled as in the analysis electromagnet 200, the outer coil 218 enters the beam entering / exiting direction from the yoke 230. The overhanging distance L ₄ can be reduced. In the conventional analysis electromagnet 40, if the coils are arranged in an inner / outer double manner, the overhang distance of the transition portion becomes very large.

  For the above reason, the analysis electromagnet 200 can be reduced in size, and the area required for the installation of the analysis electromagnet 200 can be reduced. The analysis electromagnet 200 can be reduced in weight. Further, the possibility that the magnetic field generated by the transition portions of the coils 206, 218, 212, and 224 disturbs the form of the ion beam 50 is reduced.

  In addition, since the overhang distance of the transition part of each coil 206, 218, 212, 224 can be reduced, the length of the transition part can also be shortened, so that wasteful power consumption in the transition part can be reduced. Can do.

  In addition, as described above, each coil 206, 218, 212, 224 has a structure in which the conductor sheets 268, 269 are laminated with the insulating sheets 266, 267 sandwiched therebetween, so that a multi-turn in which the coated conductor is wound many times. Compared with the coil, the space factor of the conductor is higher and the power loss is less. Therefore, power consumption can be reduced.

  For example, when the dimension a in the Y direction of each coil is 250 mm, the space factor of the conductor of the multi-turn coil of the conventional coated conductor is about 60 to 70% even when it is not hollow (not a hollow conductor). In the case of a conductor, the space factor of the conductors of the coils 206, 218, 212, and 224 can be about 84 to 85%.

  As a result, according to the analysis electromagnet 200, a magnetic field having a required strength can be generated with less power consumption than the conventional analysis electromagnet 40. It is also possible to generate a magnetic field stronger than that of the conventional analysis electromagnet 40 with the same power consumption. In the latter case, the radius of curvature R of the ion beam deflection can be reduced, and the analysis electromagnet 200 can be further downsized.

  For example, when the dimension a in the Y direction of each coil is 250 mm and a magnetic field of 0.2 Tesla is generated by the two coils 206 and 212 as in the conventional analysis electromagnet 40 (the coils 218 and 224 are not used) The power consumption of the conventional analysis electromagnet 40 is about 67 kW, whereas the power consumption of the analysis electromagnet 200 is about 24 kW.

  Since the ion implantation apparatus shown in FIG. 1 includes the analysis electromagnet 200 having the above-described features, it is possible to reduce the size of the entire ion implantation apparatus as the analysis electromagnet 200 is miniaturized. The area required for installation can be reduced. It is also possible to reduce the weight of the ion implantation apparatus. Moreover, the power consumption of the whole ion implantation apparatus can be reduced with the power consumption of the analysis electromagnet 200 being reduced.

Furthermore, since the analysis electromagnet 200 includes the first inner coil 206 and the second inner coil 212 as described above, the ion beam 50 has a larger dimension W _{Y in the} Y direction compared to the case of a single upper and lower coil. It becomes easy to respond.

  In addition, the first outer coil 218 and the second outer coil 224 can generate a sub magnetic field for correcting the main magnetic field. By this sub-magnetic field, the main magnetic field can be corrected to improve the uniformity of the magnetic flux density distribution in the Y direction. Since the sub magnetic field generated by each of the outer coils 218 and 224 may be weaker than the main magnetic field, control is easy.

By the main magnetic field and the sub magnetic field as described above, a magnetic field with high uniformity of magnetic flux density distribution in the Y direction can be generated in the beam path 202. As a result, the disorder (bending, inclination, etc., the same applies hereinafter) of the shape of the ion beam 50 when emitted from the analysis electromagnet 200 can be kept small. This effect becomes more remarkable when the dimension W _{Y in} the Y direction of the target ion beam 50 is large.

  Even if there is one each of the first outer coil 218 and the second outer coil 224, the main magnetic field can be corrected. However, as in this example, a plurality of first outer coils 218 and a plurality of second outer coils 224 are provided. It is preferable to provide the coil 224. In that case, the magnetic flux density distribution in the Y direction of the magnetic field generated in the beam path 202 can be more finely corrected by these outer coils 218 and 224, so that a more uniform magnetic field can be generated in the Y direction. it can. As a result, the disturbance of the form of the ion beam 50 at the time of extraction can be further reduced.

(2-5) Control method of analysis electromagnet 200 An example of the control method of the analysis electromagnet 200 will be described. The form of the ion beam 50 emitted from the analysis electromagnet 200 approaches the form of the ion beam 50 at the time of incidence. What is necessary is just to control the electric current sent through each 1st outer side coil 218 and each 2nd outer side coil 224. FIG.

  More specifically, in the ion beam 50 emitted from the analysis electromagnet 200, the inside of the radius of curvature R is greater than a predetermined center axis (center axis 318 shown in FIGS. 20 and 21) substantially parallel to the Y direction. The first outer coil 218 and the second outer coil 224 corresponding to the portion that is bent too much, and the first outer coil 218 and the second outer coil 218 corresponding to the portion where the inner bending is insufficient. At least one of increasing the current flowing through the outer coil 224 is performed to bring the shape of the ion beam 50 emitted from the analysis electromagnet 200 closer to that parallel to the central axis. As a result, the form of the ion beam 50 emitted from the analysis electromagnet 200 can be made straight without inclination and close to the form upon incidence.

  Examples of the form of the ion beam 50 emitted from the analysis electromagnet 200 are shown in FIGS. 20 and 21, respectively. In both figures, a predetermined central axis substantially parallel to the X direction is 318, the symmetry plane is 234, the central trajectory of the ion beam 50 is 54, and the radius of curvature is R.

  In the case of the form shown in FIG. 20, since the form of the ion beam 50 is not disturbed when viewed in the traveling direction Z of the ion beam 50, the ion beam 50 is passed through the first outer coils 218a to 218c and the second outer coils 224a to 224c. It is only necessary to maintain the current value.

  In the case of the form shown in FIG. 21, since the ion beam 50 is distorted (bent) in a circular arc shape that is close to a letter shape when viewed in the traveling direction Z, that is, the ion beam 50 is bent too much inside the radius of curvature R toward the upper side in the Y direction. Since the lower part is bent inwardly, the current flowing through the first outer coil 218a is greatly reduced, the current flowing through the first outer coil 218b is slightly reduced, and the first outer coil 218c and the second outer coil 224c are reduced. The current flowing through the second outer coil 224b is slightly reduced, and the current flowing through the second outer coil 224a is greatly reduced. As a result, while maintaining the position of the central trajectory 54 of the ion beam 50 emitted from the analysis electromagnet 200, the form thereof can be brought close to that of the central axis 318. That is, it can be brought close to the form shown in FIG.

  Even when the form of the ion beam 50 emitted from the analysis electromagnet 200 is disturbed by a pattern other than that shown in FIG. 21, it can be corrected by the same concept as described above to approximate the form shown in FIG.

  The main problem when the form of the ion beam 50 emitted from the analysis electromagnet 200 is disturbed is as follows. According to the control method, the occurrence of such a problem can be prevented.

  The analysis slit 70 shown in FIGS. 1 and 27 is usually provided on the downstream side of the analysis electromagnet 200. Since the slit 72 of the analysis slit 70 is a straight line, when the shape of the ion beam 50 is disturbed, a portion cut by the analysis slit 70 is generated, and the amount of the ion beam 50 of a desired ion species passing through the analysis slit 70 is reduced. . Since a cut portion is generated, the uniformity of the ion beam 50 is also deteriorated. If the width of the slit 72 in the X direction is increased in order to avoid cutting, the resolution decreases.

  In addition to the above problems in the analysis slit 70, when ion implantation is performed on the substrate 60 using the ion beam 50 having a disordered shape, there arises a problem that the uniformity of implantation is deteriorated.

(2-6) Another Example of Analysis Electromagnet 200 Next, another example of the analysis electromagnet 200 will be described. Portions that are the same as or correspond to those in the previous example shown in FIGS. 4 to 7 are denoted by the same reference numerals, and redundant description is omitted. Hereinafter, differences from the example will be mainly described.

  The analysis electromagnet 200 shown in FIG. 24 also refers to FIG. 22 as a coil, a pair of body portions 322 facing each other in the X direction across the beam path 202 and the direction along the Z direction of both body portions 322. Are provided with two sets of crossing portions 324 and 325 that connect the ends of the ion beam 50 avoiding the beam path 202, and a coil 320 that generates a magnetic field that bends the ion beam 50 in the X direction. In FIG. 22, the upper two transition portions 324 are one set of transition portions, and the lower two transition portions 325 are another set of transition portions.

  As shown in FIG. 23, the coil 320 has the same cross-sectional structure as the first inner coil 206 (see FIG. 10) and the inner coil 292 of the laminated coil 290 (see FIG. 15). That is, the coil 320 has a configuration in which notched portions 276 to 281 are provided in the fan-shaped cylindrical laminated coil having the same structure as the inner coil 292 except for the main body portion 322 and the transition portions 324 and 325. Yes. The coil 320 can also be made by the same manufacturing method as described above.

  The coil 320 is such that the first inner coil 206 and the second inner coil 212 (see FIG. 8) are integrated vertically into one coil.

  The notches 276 and 277 have the same shape as the notches 272 and 273. The notches 278 and 279 have a plane symmetrical shape with respect to the notches 276 and 277 and a plane of symmetry (see FIG. 24). More specifically, the notches 280 and 281 are through holes, and form the inlet 238 and the outlet 240, respectively. The ion beam 50 can pass through here. More specifically, the ion beam 50 can pass through the vacuum vessel 236.

  In order to pass the vacuum vessel 236 through the coil 320, for example, the vacuum vessel 236 may be inserted in the Z direction through the notches 280 and 281. In that case, if the vacuum vessel 236 has a flange or the like, it may be removed once. The same method may be used when assembling the analysis electromagnet 200.

  Each transition part 324 has the same structure as the transition part 210 of the first inner coil 206. Each crossover part 325 has a plane-symmetric shape with respect to each crossover part 324 and the symmetry plane 234.

The dimension a _{1 in} the Y direction of the main body 322 is substantially equal to the sum of the dimension c _{1 in} the Y direction of the transition part 324 and the dimension c _{1 in} the Y direction of the transition part 325 (ie, 2c ₁ ). Yes.

  The analysis electromagnet 200 of this example also has a structure in which the coil 320 is integrated with the first inner coil 206 and the second inner coil 212. Therefore, for the same reason as described above, the transition portion 324 of the coil 320 is used. Thus, it is possible to reduce the protruding distance of the 325 from the yoke 230 to reduce the size of the analyzing electromagnet 200 and to reduce power consumption.

  The analysis electromagnet 200 shown in FIG. 25 includes a first coil 326 and a second coil 328 that generate a magnetic field that cooperates with each other to bend the ion beam 50 in the X direction. Both the coils 326 and 328 have the same structure as the first inner coil 206 and the second inner coil 212 (see FIG. 8), respectively. Accordingly, the first coil 326 and the second coil 328 can also be produced by the same manufacturing method as described above.

  In the analysis electromagnet 200 of this example, the first coil 326 and the second coil 328 have the same structure as the first inner coil 206 and the second inner coil 212. Therefore, for the same reason as described above, The projecting distance from the yoke 230 at the transition portion can be reduced to enable the analysis electromagnet 200 to be miniaturized, and the power consumption can be reduced.

Further, since the first coil 326 and the second coil 328 as described above are provided, it is easy to deal with the ion beam 50 having a large dimension W _{Y in the} Y direction.

  The analysis electromagnet 200 shown in FIG. 26 has a structure similar to that of the coil 320 as the coil, an inner coil 330 that generates a main magnetic field that bends the ion beam 50 in the X direction, and an outer coil that is outside the inner coil 330. The first outer coil 218 and the second outer coil 224 as described above for generating a sub magnetic field for assisting or correcting the magnetic field are provided. That is, an inner coil 330 is provided instead of the first inner coil 206 and the second inner coil 212 shown in FIG. Accordingly, the inner coil 330, the first outer coil 218, and the second outer coil 224 can also be manufactured by the same manufacturing method as described above.

  A specific matter when manufacturing these coils will be described. Using the laminated coil 290 (see FIG. 14) having a required axial dimension (height), the inner coil 292 and the outer coil 294 are used. 22 is provided with a notch similar to the notches 276 to 281 in FIG. 22 by cutting or the like, and the outer coil 294 is provided with a gap similar to the gap 248 shown in FIG. 7 by cutting or the like. 218 and the second outer coil 224 may be formed. Dividing the first outer coil 218 and the second outer coil 224 into a plurality of parts is the same as in the case of FIG.

  The number of the first outer coils 218 is two in the example shown in FIG. 26, but is not limited thereto, and may be one or more. The same applies to the second outer coil 224.

  The analysis electromagnet 200 of this example also includes the inner coil 330, the first outer coil 218, and the second outer coil 224 as described above, and therefore, for the same reason as described above, the extension portion of the coil transition portion from the yoke 230 is projected. It is possible to reduce the distance to enable the analysis electromagnet 200 to be miniaturized and to reduce the power consumption.

Further, since the first outer coil 218 and the second outer coil 224 as described above are provided in addition to the inner coil 330, the magnetic flux density distribution in the Y direction is highly uniform in the beam path 202 of the ion beam 50. A magnetic field can be generated. As a result, it is possible to suppress the disturbance of the shape of the ion beam 50 during extraction. This effect becomes more remarkable when the dimension W _{Y in} the Y direction of the target ion beam 50 is large.

  Further, since the plurality of first outer coils 218 and the plurality of second outer coils 224 are provided, the magnetic flux generated in the beam path 202 by the outer coils 218 and 224 by the outer coils 218 and 224 in the Y direction as described above. Since the density distribution can be corrected more finely, a magnetic field with higher uniformity can be generated in the Y direction. As a result, the disturbance of the form of the ion beam 50 at the time of extraction can be further reduced.

  Also when the ion implantation apparatus shown in FIG. 1 includes the analysis electromagnet 200 of each of the above examples, the ion implantation apparatus as a whole can be downsized as the analysis electromagnet 200 is downsized. As a result, the ion implantation apparatus can be installed. The required area can be reduced. It is also possible to reduce the weight of the ion implantation apparatus. Moreover, the power consumption of the whole ion implantation apparatus can be reduced with the power consumption of the analysis electromagnet 200 being reduced.

(3) Focus Correction Lenses 600 and 610 Referring to FIG. 1, the ion beam 50 has a property of spreading due to the space charge that it has, so that the influence of the space charge is negligible. There is a large difference between the position of the focal point 56 and the position of the focal point 56 of the high-current ion beam 50 that cannot be ignored due to the difference in how the ion beam spreads. Specifically, in the case of the large current ion beam 50, the focal point 56 moves to the downstream side compared to the case of the small current ion beam 50. This is because the spread of the ion beam 50 due to space charge is large.

  Therefore, for example, even if the analysis slit 70 is provided at the focal position at the time of the small current ion beam, the focal point 56 is shifted from the position of the analysis slit 70 to the downstream side at the time of the large current ion beam. A decrease in efficiency and a decrease in resolution occur.

  In order to solve such a problem, the position of the focal point 56 of the ion beam 50 is set by an electrostatic field between at least one of the ion source 100 and the analysis electromagnet 200 and between the analysis electromagnet 200 and the analysis slit 70. It is preferable to provide focus correction lenses 600 and 610 for performing correction to match the position of the analysis slit 70. The bifocal correction lenses 600 and 610 belong to the category of electric field lenses (in other words, electrostatic lenses; the same applies hereinafter).

  When the focus correction lens is provided and the magnitude of the beam current of the ion beam 50 generated from the ion source 100 is variable, the analysis slit 70 is, for example, when the beam current is relatively small (for example, It may be provided near the position of the focal point 56 (at the minimum value of the variable range).

  The focus correction lenses 600 and 610 will be described in detail with reference to FIGS. FIG. 28 and FIG. 1 show a first focus correction lens 600 provided between the ion source 100 and the analysis electromagnet 200 and a first focus correction lens 600 provided between the analysis electromagnet 200 and the analysis slit 70. This is an example in which two focus correction lenses 610 are provided. However, only one of the bifocal correction lenses 600 and 610 may be provided, or both may be provided and only one of them may be used.

  When only one of the bifocal correction lenses 600 and 610 is provided or when only one of them is used, the focal point correction lens 600 and 610 corrects the position of the focal point 56 of the ion beam 50 to the position of the analysis slit 70. I do. When both the focus correction lenses 600 and 610 are provided and the bifocal correction lenses 600 and 610 are used, the two cooperate to correct the position of the focal point 56 of the ion beam 50 to the position of the analysis slit 70. Do.

  Examples of this correction are shown in FIGS. In these drawings, the trajectory of the ion beam 50 before correction is indicated by a two-dot chain line, and the trajectory after correction is indicated by a solid line.

  FIG. 30 shows that when the correction is not performed, the ion beam 50 spreads in the X direction as indicated by a two-dot chain line due to the influence of space charge, and the focal point 56 is shifted downstream from the analysis slit 70. In this example, the ion beam 50 is squeezed in the X direction by the focus correction lens 600 on the upstream side, and the position of the focus 56 is returned to the upstream side to perform the correction to match the position of the analysis slit 70.

  FIG. 31 shows that the ion beam 50 spreads in the X direction as indicated by a two-dot chain line due to the influence of space charge, and the focal point 56 shifts downstream from the analysis slit 70 unless correction is performed. In this example, the ion beam 50 is narrowed in the X direction by the focus correction lens 610 on the downstream side, and the position of the focus 56 is returned to the upstream side so as to be adjusted to the position of the analysis slit 70.

  FIG. 32 shows that when the correction is not performed, the ion beam 50 spreads in the X direction as indicated by a two-dot chain line due to the influence of space charge, and the focal point 56 is shifted downstream from the analysis slit 70. The ion beam 50 is squeezed to some extent in the X direction by the upper and downstream focus correction lenses 600 and 610, and the both focus correction lenses 600 and 610 cooperate to return the position of the focus 56 to the upstream side, thereby analyzing the slit 70. This is an example in which a correction to match the position is performed.

  As described above, the focus correction lenses 600 and 610 can correct the position of the focal point 56 of the ion beam 50 to the position of the analysis slit 70. Therefore, it is possible to prevent the focal point 56 of the ion beam 50 from being shifted from the position of the analysis slit 70 due to the influence of the space charge. As a result, it is possible to compensate for the influence of space charge and to improve both the transport efficiency and resolution of the ion beam 50.

  Comparing the example of FIG. 30 with the example of FIG. 31, in the example of FIG. 30, the ion beam 50 is narrowed by the focus correction lens 600 before the ion beam 50 spreads and hits the wall surface in the analysis electromagnet 200. Therefore, there is an advantage that the transport efficiency of the ion beam 50 can be easily improved. Accordingly, when one of the focus correction lenses 600 and 610 is used (provided), the focus correction lens 600 is preferable. However, it should be noted that if the ion beam 50 is too narrowed by the focus correction lens 600, the current density of the ion beam 50 is increased, the space charge effect is increased, and the ion beam 50 may be easily spread.

  In response to this, the ion beam 50 may be divided and focused by the bifocal correction lenses 600 and 610 as in the example of FIG. That is, the ion beam 50 is narrowed to some extent by the upstream focus correction lens 600 (specifically, the ion beam 50 is narrowed to such an extent that the ion beam 50 can pass through the analysis electromagnet 200 efficiently), and the ion beam by the downstream focus correction lens 610. 50 may be finally squeezed to adjust the focal point 56 to the position of the analysis slit 70. When the bifocal correction lenses 600 and 610 are provided and used in this manner, the focal position of the ion beam 50 can be corrected more easily and reliably, and the transport efficiency of the ion beam 50 can be further increased. The effect of compensating for the influence and improving both the transport efficiency and resolution of the ion beam 50 becomes more remarkable.

  A specific example of the configuration of the focus correction lenses 600 and 610 will be described.

  As shown in FIG. 28, the focus correction lens 600 includes an entrance electrode 602, an intermediate electrode 604, and an exit electrode 606 arranged with a gap therebetween in the traveling direction Z of the ion beam 50. These electrodes 72, 74, and 76 are arranged opposite to each other in the X direction with a gap through which the ion beam 50 passes, as in the example shown in FIG. 29, and the main surface 52 of the ion beam 50. A pair of electrodes 602a, 602b, 604a, 604b, 606a, and 606b substantially parallel to each other. Each electrode 602a, 602b, 604a, 604b, 606a, 606b is disposed substantially perpendicular to the traveling direction Z of the ion beam 50. The electrodes 602a and 602b, the electrodes 604a and 604b, and the electrodes 606a and 606b are electrically connected by conductors, respectively. That is, it is electrically conductive.

  Referring to FIG. 28, entrance electrode 602 and exit electrode 606 (specifically, electrodes 602a, 602b, 606a, and 606b constituting them) are kept at the same potential. In this example, it is kept at the ground potential. By doing so, it is possible to prevent the electric field from protruding from the focus correction lens 600 to the upstream side and the downstream side in the traveling direction Z of the ion beam 50, so that the ion beam 50 and the like are adversely affected by the protruding electric field. Can be prevented.

Intermediate electrode 604 (the electrode 604a and 604b in particular constituting it) is it (in the example shown in FIG. 28 negative) negative or positive is connected to a DC power source 608 for applying a DC voltage V ₁ of the. Due to the DC voltage V ₁ , the potential of the intermediate electrode 604 (potential with respect to the ground potential in this example) is different from the potential of the entrance electrode 602 and the exit electrode 606, and the focal point 56 of the ion beam 50 is focused on the analysis slit 70. Keep the potential to match the position. The same applies to a DC voltage V ₂ described later.

  In the focus correction lens 600, the entrance electrode 602 and the exit electrode 606 are kept at the same potential, and the intermediate electrode 604 is kept at a different potential from the entrance electrode 602 and the exit electrode 606. The ion beam 50 is narrowed down. Therefore, the ion beam 50 can be narrowed in the X direction without changing the energy of the ion beam 50.

The polarity of the DC power supply 608 may be reversed, and a positive DC voltage V ₁ may be applied to the intermediate electrode 604 of the focus correction lens 600. Also in this case, the focus correction lens 600 functions as a unipotential lens, and the ion beam 50 can be narrowed in the X direction without changing its energy. However, when a positive DC voltage V ₁ is applied, electrons in the drift space without an electric field are drawn into the intermediate electrode 604, the amount of electrons in the drift space is reduced, and the divergence due to the space charge effect of the ion beam 50 is strong. against it made of, since the negative DC voltages V ₁ such that it is possible to prevent, it is preferable to apply a negative direct-current voltage V ₁ as in the example shown in FIG. 28. The same applies to a DC voltage V ₂ described later.

As the absolute value (magnitude) of the DC voltage V ₁ applied from the DC power source 608 to the intermediate electrode 604 is increased, the ion beam 50 can be more focused. Further, the degree to which the ion beam 50 is narrowed depends on the energy of the ion beam 50 when passing through the focus correction lens 600. As the energy of the ion beam 50 increases, the deflection effect of the DC voltage V ₁ on the ion beam 50 decreases. Therefore, in order to focus the ion beam 50 strongly, the absolute value of the DC voltage V ₁ may be increased.

The focus correction lens 610 also includes an entrance electrode 602 (a pair of electrodes 602a and 602b), an intermediate electrode 604 (a pair of electrodes 604a and 604b), and an exit electrode 606 (a pair of electrodes) of the focus correction lens 600 with reference to FIG. 606a, 606b) has an inlet electrode 612 (a pair of electrodes 612a, 612b), an intermediate electrode 614 (a pair of electrodes 614a, 614b), and an outlet electrode 616 (a pair of electrodes 616a, 616b). . The intermediate electrode 614 is connected to a DC power supply 618 similar to the DC power supply 608, that is, a DC power supply 618 that applies a negative or positive (negative in the example shown in FIG. 28) DC voltage V ₂ to the intermediate electrode 614. ing. Since the configuration and operation of the focus correction lens 610 and the DC power source 618 are the same as those of the focus correction lens 600 and the DC power source 608, the description thereof is omitted here as a reference to the above description.

  When the focus correction lenses 600 and 610 have a unipotential lens configuration as described above, the focus correction lenses 600 and 610 exclusively function to narrow the ion beam 50, but when the beam current is relatively small as described above. By providing the analysis slit 70 near the focal point 56, the focus correction lens 600 indicates that the focal point 56 moves downstream of the analysis slit 70 due to the influence of space charge when the beam current is relatively large. , 610 can be well prevented. As a result, it is possible to prevent the focal point 56 of the ion beam 50 from deviating from the position of the analysis slit 70 in response to a case where the beam current of the ion beam 50 is changed to a large or small value.

The result of performing a simulation for correcting the focal position of the ion beam 50 using the focus correction lens 600 on the upstream side of the analysis electromagnet 200 will be described. An ion beam 50 containing As ⁺ , energy of 13.5 keV, and beam current of 30 mA was incident from the ion source 100 to the analysis electromagnet 200, and mass separation of As ⁺ was performed under the following conditions.

(A) When the space charge neutralization rate of the ion beam 50 is set to 100% In this case, there is no influence of the space charge on the ion beam 50. This is therefore the same as in the case of a small current ion beam. At this time, the focal point 56 of the ion beam 50 was formed at a position approximately 640 mm away from the outlet portion of the analysis electromagnet 200. In this simulation, the analysis slit 70 is not provided, but in the actual apparatus, the analysis slit 70 is provided at the position of 640 mm. An example of the beam current distribution in the X direction of the ion beam 50 at that position is shown in FIG. The vertical axis in this figure is the integrated value of the Y direction current per 1 mm in the X direction. That is, since the ion beam 50 has a ribbon shape long in the Y direction, the current value is obtained by integrating the current in the Y direction for every 1 mm in the X direction. Simply put, this figure corresponds to the current density distribution in the X direction. The same applies to the vertical axes in FIGS.

  In this case, the full width at half maximum of the beam current is about 22 mm, and the resolution m / Δm of mass analysis by the analysis electromagnet 200 is about 27.3.

(B) When the neutralization rate of the space charge of the ion beam 50 is set to 95% and the focus correction lens 600 is not operated. In this case, the ion beam 50 spreads due to the influence of the space charge. Therefore, this is the same as in the case of the high current ion beam. At this time, the focal point 56 of the ion beam 50 was formed at a position about 1,300 mm away from the outlet of the analysis electromagnet 200 on the downstream side. An example of the beam current distribution in the X direction of the ion beam 50 at the position of 640 mm in this case is shown in FIG.

  In this case, the full width at half maximum of the beam current is about 95 mm, and the resolution m / Δm of mass analysis by the analysis electromagnet 200 is about 7.1.

(C) In the case where the neutralization rate of the space charge of the ion beam 50 is set to 95% and the focal position correction is performed by the focal correction lens 600. In this case, the position is about 640 mm away from the outlet of the analysis electromagnet 200 on the downstream side. The DC voltage V ₁ applied to the intermediate electrode 604 of the focus correction lens 600 was adjusted so that the focal point 56 of the ion beam 50 was formed. The DC voltage V _{1 at} this time was −10 kV. An example of the beam current distribution in the X direction of the ion beam 50 at a position of 640 mm in this case is shown in FIG.

  In this case, the full width at half maximum of the beam current is about 42 mm, and the resolution m / Δm of mass analysis by the analysis electromagnet 200 is about 16. Compared with the case of (B) above, the resolution is improved more than twice.

Next, control of the DC voltages V ₁ and V ₂ applied to the focus correction lenses 600 and 610 will be described.

For example, as in the example shown in FIG. 28, moving the first beam current measurement device 620 of the movable measuring the beam current I _F receives the ion beam 50 which has passed through the analysis slit 70, as shown by the arrow H And inserted into the path of the ion beam 50 on the downstream side of the analysis slit 70. The beam current measuring device 620 is, for example, a Faraday cup. The beam current measuring device 620 preferably has a width K _X where the ion beam 50 that has passed through the analysis slit 70 is incident in the X direction. Regarding the Y direction, when the ion beam 50 is in the form of a ribbon, the number of beam current measuring devices 620 may be one if only one point in the Y direction can be measured. If it is desired to measure multiple points in the Y direction, the beam current measuring device 620 may be a multiple point beam current measuring device in which a plurality of measuring devices (for example, Faraday cups) are arranged in the Y direction, or one beam current measurement. A structure in which the container 620 is moved in the Y direction may be used.

Then, the beam current I _F to be measured by the beam current measuring device 620 so that the maximum, to adjust the DC voltage V _1, V ₂ to be output from the DC power source 608, 618. That is, when the focus correction lens 600 is used, the DC voltage V ₁ is adjusted. When the focus correction lens 610 is used, the DC voltage V ₂ is adjusted. When the bifocal correction lenses 600 and 610 are used, the DC voltages V ₁ and V ₂ are adjusted. More specifically, since the DC voltages V ₁ and V ₂ may be negative or positive as described above, the absolute values | V ₁ | and | V ₂ | are adjusted. Then, the DC voltages V ₁ and V _{2 at} which the beam current _IF is maximized may be maintained.

Figure 36, the absolute value DC voltage V ₁ | showing an example of a change in the beam current I _F when adjusting | V _1. Such a curve is obtained because the amount of the ion beam 50 passing through the analysis slit 70 is maximized when the position of the focal point 56 of the ion beam 50 is aligned with the analysis slit 70. In the case of this example, it is only necessary to maintain the voltage V _{1a at} which the maximum beam current _IF is obtained. A similar curve can be obtained when the absolute value | V ₂ | of the DC voltage V ₂ is adjusted.

Figure 37 shows an example of a change in the beam current I _F of the case of adjusting the absolute value of the DC voltage V ₁ and V _2. In this example, a plurality of absolute value V _1b of the direct-current voltage _{V 1, V 1c, V 1d} ( however, these three in the present invention is not limited) as parameters, the absolute value of the DC voltage V ₂ | V ₂ | a It is changing. This makes it possible to determine the DC voltage V ₁ and V ₂ to maximize the beam current I _F. In this example, the voltages V _1d and V _{2a at} which the maximum beam current I _F can be obtained may be maintained. Contrary to the case of FIG. 37, the absolute value of the DC voltage V ₁ may be changed using a plurality of absolute values of the DC voltage V ₂ as parameters.

According to the adjustment method described above, the measurement beam current _IF is maximized when the position of the focal point 56 of the ion beam 50 is aligned with the analysis slit 70. Therefore, the focal position of the ion beam 50 is analyzed by the focus correction lenses 600 and 610. It is possible to easily perform correction to match.

As the beam current I _F to be measured by the beam current measuring device 620 is maximized, the control contents similar to the above adjusting method, the DC voltage V _1, V ₂ (more specifically the output from the DC power source 608, 618 May include a first focus control device 622 (see FIG. 28) for controlling their absolute values | V ₁ |, | V ₂ |). Thus, correction for adjusting the focal position of the ion beam 50 to the analysis slit 70 can be performed while saving labor.

As in the example shown in FIG. 38, by using the second beam current measuring device 624 that measures the beam current I _S flowing through the analysis slit 70, the beam current I _S to be measured by the beam current measuring device 624 is minimized As described above, the DC voltages V ₁ and V ₂ (more specifically, absolute values | V ₁ | and | V ₂ | thereof) output from the DC power supplies 608 and 618 may be adjusted. In this case, the analysis slit 70 is electrically insulated from a structure such as a vacuum vessel and grounded via the beam current measuring device 624. Examples of proper use or combination of the DC voltages V ₁ and V ₂ are the same as described above.

FIG. 39 shows an example of a change in the beam current I _S when adjusting the absolute value | V ₁ | of the DC voltage V ₁ . Such a curve is obtained because the amount of the ion beam 50 that strikes the analysis slit 70 is minimized when the position of the focal point 56 of the ion beam 50 is aligned with the analysis slit 70. In the case of this example, the voltage V _{1e at} which the minimum beam current I _S can be obtained may be maintained. A similar curve can be obtained when the absolute value | V ₂ | of the DC voltage V ₂ is adjusted.

When one of the DC voltages V ₁ and V ₂ is used as a parameter and the other is changed, a curve obtained by inverting the curve of FIG. 37 in a valley shape is obtained.

According to the above adjustment method, the measurement beam current I _S is minimized when the position of the focal point 56 of the ion beam 50 is aligned with the analysis slit 70, so that the focal position of the ion beam 50 is analyzed by the focus correction lenses 600 and 610. It is possible to easily perform correction to match.

The DC voltages V ₁ and V ₂ output from the DC power supplies 608 and 618 (more specifically, in accordance with the same control contents as in the above adjustment method so that the beam current I _S measured by the beam current measuring device 624 is minimized. May include a second focus control device 626 (see FIG. 38) for controlling their absolute values | V ₁ |, | V ₂ |). Thus, correction for adjusting the focal position of the ion beam 50 to the analysis slit 70 can be performed while saving labor.

(4) Accelerator / Decelerator 400 The accelerator / decelerator 400 shown in FIG. 1 deflects the ion beam 50 that has passed through the analysis slit 70 in the X direction by an electrostatic field, and accelerates or accelerates the ion beam 50 by the electrostatic field. Decelerates. The accelerator / decelerator 400 is preferably provided on the downstream side as much as possible in order to exhibit the effect of suppressing energy contamination, which will be described later, more effectively. In the example shown in FIG. 1, the analysis slit 70 is provided between the injection position, in other words, between the analysis slit 70 and the substrate driving device 500.

  When such an accelerator / decelerator 400 is provided, not only the acceleration / deceleration of the ion beam 50 but also the ion beam 50 can be deflected in the X direction. Can be selected and derived, and energy contamination (mixing of undesired energy ions) can be suppressed. In addition, since these actions can be realized by one accelerator / decelerator 400, the transport path of the ion beam 50 can be shortened as compared with a case where a separate energy separator is provided, and thereby the ion beam 50 Transport efficiency can be improved. In particular, when the ion beam 50 has a low energy and a large current, the ion beam 50 is likely to diverge due to the space charge effect during transportation, so that the effect of shortening the transport distance becomes significant.

  A more specific example of the accelerator / decelerator 400 is shown in FIG. The acceleration / decelerator 400 includes first to third electrodes 402 arranged in the order of the first electrode 402, the second electrode 404, and the third electrode 406 from the upstream side in the traveling direction of the ion beam 50. 404 and 406. In this example, the electrodes 402 and 406 respectively have openings 412 and 416 that extend long in the Y direction and allow the ion beam 50 to pass therethrough. In this example, the electrode 402 is a single electrode, but it may be composed of two electrodes having the same potential sandwiching the path of the ion beam 50 in the X direction. The same applies to the electrode 406. The electrode 404 extends long in the Y direction and has a gap 414 through which the ion beam 50 passes.

  A potential V1 is applied to the first electrode 21 with reference to the ground potential. This potential V1 is normally a positive (positive in acceleration mode) or negative (deceleration mode) high potential.

  When a potential is applied to each electrode 402, 404, 406 or each electrode body 404a, 404b described later, if the potential is other than 0V, voltage applying means (for example, a DC power source or a DC The potentials are applied from voltage dividing resistors that divide the voltage from the power supply (not shown, the same applies hereinafter). When the potential is 0V, the electrode is grounded.

  The second electrode 404 is usually set to an intermediate potential between the first electrode 402 and the third electrode 406. The second electrode 404 is one electrode in a known electrostatic acceleration tube, but in this example, the second electrode 404 is divided into two electrode bodies 404a and 404b facing each other across the path of the ion beam 50 in the X direction. It is configured. Moreover, different potentials V2a and V2b (V2a ≠ V2b) are respectively applied to the electrode bodies 404a and 404b, thereby deflecting the ion beam 50 in the X direction. More specifically, a potential V2b lower than the potential V2a of the counterpart electrode body 404a is applied to the electrode body 404b in the direction in which the ion beam 50 is deflected. That is, V2b <V2a. The means for applying such a potential is as described above.

  The gap 414 through which the ion beam 50 passes is provided between the two electrode bodies 404 a and 404 b constituting the electrode 404. The gap 414 is preferably bent in the deflection direction of the ion beam 50 as in this example. More specifically, it is preferable to bend along the trajectory of an ion 418 having a specific energy after deflection, specifically having a desired energy. By doing so, the ion beam 50 composed of the ions 418 having the desired energy can be efficiently derived.

  The third electrode 406 is usually supplied with a potential V3 of 0V. That is, it is grounded.

  As in this example, the electrode 406 on the downstream side of the second electrode 404 is arranged along the trajectory of ions 418 having a specific energy, specifically, a desired energy after being deflected by the electrode 404. Is preferred. By doing so, ions 418 having desired energy can be efficiently derived, and ions 420, 422 and neutral particles 424 having other energies can be efficiently blocked by the electrode 406. Therefore, energy contamination can be suppressed more effectively.

The degree to which the difference between the potentials V2a and V2b applied to the electrode bodies 404a and 404b constituting the second electrode 404 is set depends on the ion 418 having the desired (target) energy. 400 center trajectory of, specifically set to pass through the second electrode 404 after the electrode 404, 406 (more specifically Waso these gaps 414 and openings 416) centered path having a deflecting function It ’s fine.

  Examples of potentials applied to the electrodes and electrode bodies are summarized in Table 1. Examples 1 and 2 are for the acceleration mode in which the ion beam 50 is accelerated by the accelerator / decelerator 400, and Example 3 is for the deceleration mode in which the ion beam 50 is decelerated. In the case of Example 1, an acceleration energy of 30 keV can be realized, and in the case of Example 2, an acceleration energy of 130 keV can be realized. In the case of Example 3, deceleration energy of 8 keV can be realized. In any case, the potential V2b of one electrode body 404b constituting the second electrode 404 is set lower than the potential V2a of the counterpart electrode body 404a.

  According to the acceleration / deceleration device 400, the ion beam 50 can be deflected at the portion of the second electrode 404 that is divided into two electrode bodies 404a and 404b and to which different potentials V2a and V2b are applied. Since the deflection amount at this time depends on the energy of the ion beam 50 at the time of deflection, the ions 418 having the desired energy and the ions 420 and 422 having the other energy can be separated. The ion 420 is an ion having a lower energy than the desired energy, and the amount of deflection is larger than that of the ion 418. The ions 422 are ions having higher energy than desired energy, and the amount of deflection is smaller than that of the ions 418. Since the neutral particles 424 travel straight without being deflected, they can also be separated. That is, since the acceleration / decelerator 400 has an energy separation function, the ion beam 50 composed of ions 418 having a desired energy can be selected and derived, and energy contamination can be suppressed. In this example, ions 420 and 422 and neutral particles 424 other than the ion 418 having the desired energy are blocked and removed by colliding with the electrode 406 on the downstream side of the second electrode 404.

  In addition, the accelerator / decelerator 400 also has an original function of accelerating or decelerating the ion beam 50 as well as the energy separation action as described above, and these actions can be realized in one accelerator / decelerator 400. It is not necessary to provide a separate energy separator. Therefore, compared with the case where an energy separator is provided separately, the transport distance of the ion beam 50 can be shortened, and thereby the transport efficiency of the ion beam 50 can be improved.

  Further, the ion beam 50 can be accelerated in two stages between the electrodes 402 and 404 and between the electrodes 404 and 406. Example 2 in Table 1 shows an example. Since the ion beam 50 can be deflected by the electrode 404 before acceleration in the subsequent stage (that is, when the energy is low), the ion beam 50 can be easily deflected as compared with the case where the ion beam 50 is deflected after acceleration. become. More specifically, since the difference between the potentials V2a and V2b applied to the two electrode bodies 404a and 404b constituting the electrode 404 is small, there is an advantage that electrical insulation around the electrode 404 is facilitated.

  In addition, ions other than ions 418 having desired energy and neutral particles can be blocked and removed by the electrode 406 on the downstream side of the electrode 404, so that energy contamination can be more effectively suppressed. In particular, in the deceleration mode (see Example 3 in Table 1), it is empirically known that neutral particles 424 are likely to be generated by charge conversion during deceleration of the ion beam 50 between the electrodes 402 and 404. Even if many particles 424 are generated, they travel straight and collide with the electrode 406 to be blocked, so that the neutral particles 424 can be effectively removed in the accelerator / decelerator 400.

  Normally, in the acceleration mode, electrons are emitted and accelerated to the high potential side from the location where ions of energy other than the desired energy collide with the electrode, and the energy of the accelerated electron is changed from the portion of the electrode where such accelerated electrons collide. Corresponding high energy X-rays are generated. Since the known electrostatic accelerator tube does not have a deflection function, the accelerated electrons can reach the high potential electrode (electrode corresponding to the electrode 402) without being bent, and the potential of the high potential electrode is reached. It is accelerated by corresponding large energy and collides with a high potential electrode, and X-rays with large energy are generated therefrom.

  On the other hand, if the second electrode 404 is divided into two electrode bodies 404a and 404b as in the acceleration / decelerator 400 and a different potential is given to them to have a deflection function, Electrons generated from a location where ions of desired energy collide are bent at the electrode 404 and cannot reach the high-potential electrode 402. Specifically, the electrons are bent toward the high potential side electrode body 404a of the two electrode bodies 404a and 404b constituting the electrode 404 and collide with the electrode body 404a. The acceleration energy of the electrons at this time is energy corresponding to the potential of the electrode body 404 a and is smaller than that in the case of colliding with the high-potential electrode 402. For example, in the case of Example 1 in Table 1, the energy of collision electrons is almost 0 eV, and almost no X-rays are generated. In the case of Example 2, it is about 100 keV, which is smaller than about 130 keV when colliding with the electrode 402. Therefore, in any case, the energy of X-rays generated therefrom can be made lower than that of a known electrostatic accelerator tube.

  Note that another electrode may be further provided on the upstream side of the electrode 402 or the downstream side of the electrode 406 as necessary. For example, a high-potential electrode for accelerating or decelerating the ion beam 50 may be provided on the upstream side of the electrode 402. A negative potential electrode for suppressing backflow electrons from the downstream side may be provided on the downstream side of the electrode 406.

(5) Trajectory Control Lenses 700a and 700b In an ion implantation apparatus that performs ion implantation by irradiating the substrate 60 with the ribbon-like ion beam 50 as described above, the trajectory state in the Y direction, which is the longitudinal direction of the ion beam ( For example, parallel, divergent or focused states are important. For example, the parallelism of the ion beam 50 in the Y direction is important in order to perform ion implantation with good uniformity over a wide region (for example, substantially the entire surface) of the substrate 60.

  In order to respond to this, the following trajectory control lens 700a or 700b may be provided between the analyzing electromagnet 200 and the accelerometer 400. Both trajectory control lenses 700a and 700b belong to the category of electric field lenses.

  In the example illustrated in FIG. 1, a trajectory control lens 700 a that bends the ion beam 50 passing therethrough in the Y direction by an electrostatic field is provided between the analysis slit 70 and the acceleration / decelerator 400. However, the trajectory control lens 700a may be provided between the analysis electromagnet 200 and the analysis slit 70 (for example, between the focus correction lens 610 and the analysis slit 70 when the focus correction lens 610 is provided). The same applies to the trajectory control lens 700b described later.

The trajectory control lens 700a also includes an entrance electrode 702, an intermediate electrode 704, and an exit electrode 706 arranged in series with gaps 708 and 710 in the traveling direction Z of the ion beam 50 with reference to FIG. . The length in the Y direction of these electrodes 702, 704, and 706 is slightly larger than the dimension W _{Y in} the Y direction of the ion beam 50 to be passed, and is, for example, about 400 mm to 500 mm. The distance between the gaps 708 and 710 in the YZ plane is, for example, about 40 mm to 50 mm. However, it is not restricted to these dimensions.

The entrance electrode 702 includes a pair of electrodes 702a and 702b that are arranged to face each other in the X direction with a gap 712 through which the ion beam 50 passes. The intermediate electrode 704 has a pair of electrodes 704 a and 704 b that are arranged to face each other in the X direction with a gap 714 through which the ion beam 50 passes. The exit electrode 706 has a pair of electrodes 706a and 706b that are arranged to face each other in the X direction with a gap 716 through which the ion beam 50 passes. The dimension in the X direction of each gap 712, 714, 716 may be determined according to the dimension W _X in the X direction of the ion beam 50 to be passed, and is, for example, about 50 mm to 100 mm. However, it is not limited to this dimension.

  The electrodes 702a and 702b are electrically connected to each other and at the same potential by a conductive means such as a conductive wire (not shown). The same applies to the electrodes 704a and 704b. The same applies to the electrodes 706a and 706b.

  The intermediate electrode 704 has convex surfaces 720 and 722 that are curved in an arc shape in the Y direction on the upstream and downstream surfaces in the traveling direction Z of the ion beam 50, respectively. Both convex surfaces 720 and 722 are not curved in the X direction in this example. The entrance electrode 702 and the exit electrode 706 are concave surfaces 718 and 724 along the convex surfaces 720 and 722 (more specifically, at equal intervals) on the surfaces facing the convex surfaces 720 and 722 of the intermediate electrode 704, respectively. Respectively. Accordingly, the gaps 708 and 710 are also curved in an arc shape in the Y direction, but are not curved in the X direction.

  The entrance electrode 702 and the exit electrode 706 are electrically connected to each other by conducting means such as a conducting wire 730, and are kept at the same potential. Both electrodes 702, 706 are kept at ground potential in this example. By doing so, it is possible to prevent the electric field from protruding from the trajectory control lens 700a to the upstream side and the downstream side in the traveling direction Z of the ion beam 50, so that the ion beam 50 and the like are adversely affected by the protruding electric field. Can be prevented.

  The intermediate electrode 704 has a potential different from that of the entrance electrode 702 and the exit electrode 706, and is maintained at a potential that makes the trajectory state of the ion beam 50 derived from the trajectory control lens 700a desired in the Y direction. An example of this orbital state will be described later with reference to FIGS. Between the entrance electrode 702 and the exit electrode 706 and the intermediate electrode 704, a voltage variable DC power source 732 that maintains the intermediate electrode 704 at the above-described potential is connected. In the example shown in FIG. 41, the direction of the DC power source 732 is the negative electrode on the intermediate electrode 704 side, but it may be reversed.

  In this trajectory control lens 700a, the entrance electrode 702 and the exit electrode 706 are kept at the same potential, and the intermediate electrode 704 is kept at a different potential from the entrance electrode 702 and the exit electrode 706. To do. Therefore, by providing such a trajectory control lens 700a, the trajectory state in the Y direction of the ion beam 50 can be made desired without changing the energy of the ion beam 50. An example of this will be described below.

  FIG. 42 shows that when the intermediate electrode 704 is kept at a lower potential than the entrance electrode 702 and the exit electrode 706, more specifically, the entrance electrode 702 and the exit electrode 706 are kept at 0V, and the intermediate electrode 704 is set to −15,000V. An example of the distribution of equipotential lines 728 in the vicinity of the gaps 708 and 710 between the electrodes on the YZ plane at the center in the X direction of the trajectory control lens 700a when X is applied (that is, the coordinate of X = 0). It is shown. An equipotential line 728 curved in a convex lens shape is formed.

  When ions constituting the ion beam 50 are incident on the trajectory control lens 700a having the distribution of the equipotential lines 728 as described above, a focusing effect is generated in the Y direction. Thus, for example, the diverging incident ion beam 50 can be derived as a parallel beam. The parallel incident ion beam 50 can be derived as a focused beam. If the negative potential of the intermediate electrode 704 is further increased, the diverging incident ion beam 50 can be derived as a focused beam. Further, if the polarity of the intermediate electrode 704 is reversed from the above to be a positive potential, the ion beam 50 can be diverged in the Y direction.

  In the same manner as described above, a voltage of 0 V is applied to the entrance electrode 702 and the exit electrode 706, and a voltage of -15,000 V is applied to the intermediate electrode 704, and an ion beam 50 composed of energy 15 keV and monovalent arsenic (As) ions (atomic weight 75 AMU) An example in the case of entering the trajectory control lens 700a is shown in FIGS. Although not illustrated, equipotential lines similar to those shown in FIG. 42 are formed in the vicinity of the gaps 708 and 710 in FIGS. 43 to 45 and 47 are on the YZ plane at the coordinate of X = 0 as in FIG.

  FIG. 43 shows an example in which the incident ion beam 50 diverging in the Y direction is derived as a parallel beam. In this example, the divergence angle of the incident ion beam 50 is ± 1 ° to ± 9 ° (the central portion in the Y direction is ± 1 °, and is increased by 1 ° as it deviates vertically from there). In this specification, as shown in FIG. 43, the parallel beam is an ion beam having trajectories (traveling directions) of ion beams 50 respectively derived from different positions in the Y direction and substantially parallel to each other. Say that. In this example, it is also parallel to the Z direction, which is the traveling direction of the entire ion beam 50.

  FIG. 44 shows an example in which the incident ion beam 50 that is parallel in the Y direction (that is, the divergence angle is 0 degree, the same applies hereinafter) is derived as a focused beam. Since the ion beam 50 has a property of diverging due to the space charge effect, the ion beam 50 having a low energy and a large beam current is particularly strong, so that the ion beam focused from the trajectory control lens 700a as in this example is used. By taking out 50 and balancing (cancelling) the divergence caused by the space charge effect between the trajectory control lens 700a and the substrate 60, the ion beam 50 incident on the substrate 60 can be made into a substantially parallel beam. .

FIG. 45 shows an incident ion consisting of 15 keV energy and monovalent arsenic ions in the same manner as described above when a voltage of 0 V is applied to the inlet electrode 702 and the outlet electrode 706 and +10,000 V is applied to the intermediate electrode 704, as described above. An example in which the beam 50 is derived as a divergent beam is shown. A beam focusing means is provided on the downstream side of the trajectory control lens 700a, and the ion beam 50 can be collimated by combining the divergence by the former and the focusing by the latter. By doing so, the dimension W _Y in the Y direction of the ion beam 50 can be further increased.

  By providing the trajectory control lens 700a as described above, the trajectory state in the Y direction of the ion beam 50 can be made desired without changing the energy of the ion beam 50. For example, the ion beam 50 can be converted into a parallel beam to derive the ion beam 50 with high parallelism. Therefore, it is suitable when, for example, it is not desired to change the energy of the ion beam 50 when making the beam parallel.

  By converting the ion beam 50 derived from the trajectory control lens 700a into a parallel beam, for example, ion implantation with good uniformity can be performed over a wide region (for example, substantially the entire surface) of the substrate 60. Further, it is possible to prevent a shadow portion where the ion beam 50 is not incident on the fine structure portion on the surface of the substrate 60.

  Moreover, the intermediate electrode 704 constituting the trajectory control lens 700a has the convex surfaces 720 and 722 curved in the Y direction as described above, and the inlet electrode 702 and the outlet electrode 706 have concave surfaces 718 and 724 along the convex surfaces 718 and 724, respectively. Therefore, the uniformity of the electric field distribution in the gaps 708 and 710 between the electrodes in the Y direction becomes very good (see FIG. 42). As a result, even when the dimension in the Y direction is large, the orbital state of the ion beam 50 in the Y direction can be made desirable with good uniformity. Therefore, it is particularly suitable when the ribbon-like ion beam 50 is used. If the surfaces 718 and 724 of the inlet electrode 702 and the outlet electrode 706 are flat or the surfaces 720 and 722 of the intermediate electrode 704 are flat, the gaps 708 and 710 are spaced at intervals of the plurality of equipotential lines 728. Since wide and narrow non-uniformity occurs in the Y direction, the uniformity of the electric field distribution in the gaps 708 and 710 in the Y direction is reduced.

  FIG. 46 is a perspective view showing another example of the trajectory control lens together with the power source. Such a trajectory control lens 700b may be provided instead of the trajectory control lens 700a. Note that the same or corresponding parts as those of the trajectory control lens 700a shown in FIG. 41 and the like are denoted by the same reference numerals, and the difference from the trajectory control lens 700a will be mainly described below.

  The intermediate electrode 704 constituting the trajectory control lens 700b has concave surfaces 721 and 723 that are curved in an arc shape in the Y direction on the upstream and downstream surfaces in the traveling direction Z of the ion beam 50, respectively. In this example, the biconcave surfaces 721 and 723 are not curved in the X direction. The entrance electrode 702 and the exit electrode 706 are convex surfaces 719 and 725 along the concave surfaces 721 and 723 (more specifically, at equal intervals) along the surfaces corresponding to the concave surfaces 721 and 723 of the intermediate electrode 704, respectively. Respectively. Accordingly, the gaps 708 and 710 are also curved in an arc shape in the Y direction, but are not curved in the X direction.

  The intermediate electrode 704 has a potential different from that of the entrance electrode 702 and the exit electrode 706, and is maintained at a potential that makes the trajectory state in the Y direction of the ion beam 50 derived from the trajectory control lens 700b desired. An example of this orbital state will be described later with reference to FIG. Between the entrance electrode 702 and the exit electrode 706 and the intermediate electrode 704, a voltage variable DC power source 732 that maintains the intermediate electrode 704 at the above-described potential is connected. The direction of the DC power source 732 is the positive electrode on the intermediate electrode 704 side in the example shown in FIG. 46, but it may be reversed.

  In the vicinity of the gaps 708 and 710 of the trajectory control lens 700b, equipotential lines curved in a concave lens shape opposite to the example shown in FIG. 42 are formed.

  In this trajectory control lens 700b, the entrance electrode 702 and the exit electrode 706 are kept at the same potential, and the intermediate electrode 704 is kept at a different potential from the entrance electrode 702 and the exit electrode 706. To do. Therefore, by providing such a trajectory control lens 700b, the trajectory state in the Y direction of the ion beam 50 can be made desired without changing the energy of the ion beam 50.

  That is, when ions enter the trajectory control lens 700b, a focusing effect is generated in the Y direction. Thus, for example, as shown in FIG. 47, the diverging incident ion beam 50 can be derived as a parallel beam. 47 shows that when the intermediate electrode 704 is kept at a higher potential than the entrance electrode 702 and the exit electrode 706, more specifically, the entrance electrode 702 and the exit electrode 706 are kept at 0V, and the intermediate electrode 704 has a voltage of + 15,000V. It is an example when is applied. The incident ion beam 50 is composed of energy 15 keV and monovalent arsenic ions, and the divergence angle is ± 1 ° to ± 9 °.

  In addition, the trajectory control lens 700b can also derive the parallel incident ion beam 50 as a focused beam. If the positive potential of the intermediate electrode 704 is further increased, the diverging incident ion beam 50 can be derived as a focused beam. In addition, if the polarity of the intermediate electrode 704 is reversed to a negative potential, the ion beam 50 can be diverged in the Y direction.

  Since the other functions and effects of the trajectory control lens 700b are the same as those of the trajectory control lens 700a described above, redundant description is omitted here.

(6) About the homogenizing lens 750 Instead of the trajectory control lenses 700a and 700b, a homogenizing lens 750 as shown in FIGS. 48 and 49 may be provided. The homogenizing lens 750 belongs to the category of an electric field lens.

  The homogenizing lens 750 is provided between the analysis electromagnet 200 and the accelerator / decelerator 400. More specifically, it may be provided between the analysis slit 70 and the accelerometer 400, or between the analysis electromagnet 200 and the analysis slit 70 (when the focus correction lens 610 is provided, for example, focus correction). It may be provided between the lens 610 and the analysis slit 70.

  The homogenizing lens 750 includes a plurality of pairs (electrode pairs) of electrodes 752 that are arranged opposite to each other in the X direction with a gap through which the ion beam 50 passes and are electrically connected to each other in the Y direction. The beam current density distribution in the Y direction of the ion beam 50 at the implantation position is made uniform by bending a plurality of orbits in the Y direction of the ion beam 50 in the Y direction by an electrostatic field.

  More specifically, the homogenizing lens 750 is a pair of electrodes 752 (electrode pairs) facing each other across the ion beam 50 in the X direction, and a plurality of (for example, 10) arranged in multiple stages in the Y direction. A pair of electrodes. Each electrode 752 has a semi-cylindrical shape or a semi-cylindrical shape in the vicinity of the opposite ends in the illustrated example. As shown in FIG. 49, the two electrodes 752 that form a pair opposite to each other are electrically connected in parallel and are electrically connected. In FIG. 49, it may seem that the line for parallel connection crosses the ion beam 50, but this is because the illustration is simplified, and the above line does not actually cross the ion beam 50. .

  As an example of a uniform lens power source that applies independent DC voltages to each other between the electrode pairs at each stage and a reference potential portion (for example, a ground potential portion), in this example, each pair of electrode pairs is independent. A variable voltage uniformizing lens power source 754 is provided. That is, as many equalization lens power supplies 754 as the number of electrode pairs are provided. However, instead of doing so, the DC voltage applied to each electrode pair can be controlled independently of each other by using a single uniform lens power supply by, for example, combining a plurality of power supplies together. May be.

  The DC voltage applied to the electrode pairs in each stage is preferably a negative voltage rather than a positive voltage. When a negative voltage is used, it is possible to prevent electrons in the plasma existing around the ion beam 50 from being drawn into the electrode 752. When the electrons are drawn, the divergence of the ion beam 50 due to the space charge effect increases, but this can be prevented.

By adjusting the DC voltage applied to the electrode pair at each stage, an electric field E _Y is generated in the Y direction in the path of the ion beam 50 (the electric field E _{Y in} FIG. 49 shows an example thereof). Depending on the strength of _Y , ions constituting the ion beam 50 can be bent in the Y direction.

  Therefore, the uniform lens 750 bends orbits at a plurality of locations in the Y direction of the ion beam 50 in the Y direction by an electrostatic field, and uniformizes the beam current density distribution in the Y direction of the ion beam 50 at the implantation position. be able to. As a result, the uniformity of ion implantation with respect to the substrate 60 can be further improved. This effect becomes more prominent when the substrate 60 and thus the dimension of the ion beam 50 in the Y direction are large.

  A beam measuring device 80 and a uniformization control device 90 for measuring the beam current density distribution in the Y direction of the ion beam 50 at the implantation position are provided (see FIG. 1), and the following control is performed using them. You may make it do.

In this example, the beam measuring device 80 is a multi-point beam measuring device in which a large number of measuring devices (for example, Faraday cups) for measuring the beam current of the ion beam 50 are arranged in parallel in the Y direction. It is also possible to use a structure that moves the lens in the Y direction by a moving mechanism. Measurement information D ₁ representing the beam current density distribution is output from the beam measuring instrument 80 and supplied to the homogenization controller 90. The measurement information D ₁ is composed of a plurality of n ₁ pieces of measurement information (n ₁ is the same as the number of Faraday cups).

Based on the measurement information D ₁ from the beam measuring device 80, the homogenization control device 90 gives a plurality of n ₂ (n ₂ is the same as the number of electrode pairs) control signals S ₂ to each homogenization lens power source 754. Thus, the uniformity of the beam current density distribution is controlled by controlling each of the homogenizing lens power supplies 754. More specifically, when there is a low current density region where the beam current density is lower than the others, the homogenization control device 90 applies an electric field from the next to the region in the homogenization lens 750 corresponding to the low current density region. The voltage applied to the electrode pair corresponding to the low current density region is decreased so that E _Y is directed, and vice versa (ie, the voltage is increased to decrease the electric field E _Y , or vice versa). The beam current density distribution in the Y direction of the ion beam 50 at the implantation position is made uniform.

  As shown in FIG. 48, shielding plates 756 and 758 may be provided on the upstream side and the downstream side of the electrode 752 constituting the homogenizing lens 700. Each of the shielding plates 756 and 758 has a length that covers the entire electrode 752 arranged in the plurality of stages in the Y direction, and is electrically grounded. If the shielding plates 756 and 758 are provided, it is possible to prevent the electric field from leaking from the electrode 752 to the upstream side and the downstream side of the homogenizing lens 750. As a result, it is possible to prevent the ion beam 50 from being undesirably bent due to an undesired electric field acting on the ion beam 50 in the vicinity of the upstream side and the downstream side of the homogenizing lens 750.

(7) About the deflection electromagnet 800 Instead of the trajectory control lenses 700a and 700b and the uniformizing lens 750, a deflection electromagnet 800 as shown in the example shown in FIGS. 50 and 53 may be provided. It can be said that the deflection electromagnet 800 is a kind of magnetic lens.

  The deflection electromagnet 800 is provided between the analysis electromagnet 200 and the implantation position (that is, the position where the ion beam 50 is incident on the substrate 60). For example, it is provided between the analysis electromagnet 200 and the accelerator / decelerator 400. More specifically, it may be provided between the analysis slit 70 and the accelerometer 400, or between the analysis electromagnet 200 and the analysis slit 70 (when the focus correction lens 610 is provided, for example, focus correction). It may be provided between the lens 610 and the analysis slit 70.

  FIG. 50 is a front view showing an example of a deflection electromagnet together with a power source. FIG. 51 is a side view taken along line MM in FIG. 50, and shows an example in which a divergent beam is converted into a parallel beam.

The deflecting electromagnet 800 receives the ribbon-like ion beam 50 and generates magnetic fields B ₁ and B ₂ along the X direction in a beam path 802 that is a path of the ion beam 50. The deflecting electromagnet 800 is opposed to each other in the X direction with the beam path 802 interposed therebetween, and is almost half or more (in other words, substantially half or more) of one side of the ion beam 50 in the Y direction (upper side in this embodiment). ) And a first magnetic pole pair 810 having a pair of magnetic poles 812 that are opposed to each other in the X direction across the beam path 802 and on the other side in the Y direction of the ion beam 50 (the lower side in this embodiment). A second magnetic pole pair 820 having a pair of magnetic poles 822 covering approximately half or more (in other words, substantially more than half), a gap 816 between the first magnetic pole pair 810, and a gap 826 between the second magnetic pole pair 820; Coils 834 to 837 that generate magnetic fields B ₁ and B ₂ opposite to each other are provided.

The length (gap length; hereinafter the same) G ₁ of the gap 816 between the first magnetic pole pair 810 in the X direction is substantially constant in the Y direction. The gap length G ₂ between the second magnetic pole pair 820 is also substantially constant in the Y direction. Further, it is preferable that the gap lengths G ₁ and G ₂ have substantially the same length as each other, and in this example, they are so.

In this example, coils 834 and 835 are wound around a pair of magnetic poles 812 constituting the first magnetic pole pair 810, respectively. Both coils 834 and 835 is connected to a DC power source 840 are serially connected to each other, this being energized by a DC power source 840, for example in the X direction to generate a magnetic field B ₁ of the right as shown in Figure 50.

Coils 836 and 837 are wound around a pair of magnetic poles 822 constituting the second magnetic pole pair 820, respectively. Both coils 836 and 837 are connected in series to each other and connected to a DC power supply 842. By this DC power supply 842, an excitation current in the direction opposite to that of the coils 834 and 835 is caused to flow, for example, as shown in FIG. The magnetic field B ₂ facing leftward in the X direction is generated.

However, the winding method and number of coils, the DC power source for the coils, etc. are not limited to this example. For example, all the coils 834 to 837 may be connected in series and excited by one DC power source. Further, a coil may be wound only on one of the left and right magnetic poles 812 and the left and right magnetic poles 822. A coil may be wound around both or one of the yokes 830 and 832 described later. In any case, magnetic fields B ₁ and B ₂ opposite to each other are generated. The same applies to the examples shown in FIGS.

In this deflection electromagnet 800, as shown in FIG. 51, the lengths L ₆ and L ₇ in the ion beam traveling direction Z of the magnetic poles 812 and 822 constituting the first magnetic pole pair 810 and the second magnetic pole pair 820, respectively, In the Y direction, the distance increases from the center (804) of the beam path 802 to the outside (up and down). Accordingly, the side surface shape of each of the magnetic poles 812 and 822 has a shape close to a triangle or a wedge shape whose outer side in the Y direction is wide. Each magnetic pole 812 and each magnetic pole 822 preferably has a substantially plane-symmetric shape in the Y direction with respect to a symmetry plane 806 passing through the center 804 in the Y direction of the beam path 802 and parallel to the XZ plane. Then it is like that.

  When this deflection electromagnet 800 is exclusively used for collimating the diverging ion beam 50, the entrance surfaces 813 and 823 of the magnetic poles 812 and 822 are set in the ion beam traveling direction Z as shown in the example shown in FIG. It is preferable to have a swollen arc shape and to make the exit surfaces 814 and 824 linear. By doing so, the incident angle and the exit angle of the ion beam 50 with respect to the entrance surfaces 813 and 823 and the exit surfaces 814 and 824 can be made close to a right angle at any position in the Y direction. .

  In this example, the coils 834 to 837 are wound along the magnetic poles 812 and 822 and deformed from the rectangular shape, but are not necessarily wound along the same. The shape may be close to a rectangle. This is because the shapes of the magnetic poles 812 and 822 are important.

Since this deflection electromagnet 800 generates magnetic fields B ₁ and B ₂ opposite to each other in the gap 816 between the first magnetic pole pair 810 and the gap 826 between the second magnetic pole pair 820, the gaps 816 and 826 are generated. As shown in FIG. 51, Lorentz forces F ₁ and F ₂ received by the ion beam 50 passing through each of the ion beams 50 are inward. Therefore, the ion beam 50 is narrowed.

In addition, the lengths L ₆ and L ₇ in the ion beam traveling direction Z of the magnetic poles 812 and 822 constituting the first magnetic pole pair 810 and the second magnetic pole pair 820 are separated from the center 804 of the beam path 802 in the Y direction. Therefore, the ion beam 50 is more strongly bent as it passes between the magnetic poles 812 and 822 longer (longer distance) as it is further away from the center 804 of the beam path 802 in the Y direction. Thereby, the orbital state of the ion beam 50 in the Y direction can be controlled.

  For example, when focusing on the Y direction, the ion beam 50 has a property of diverging in the Y direction due to the space charge effect. However, the divergence angle is generally the center of the Y direction as shown in FIG. It is small in the vicinity of 804 and large as it goes away from the center 804. This is because the divergence is greater at the edge.

On the other hand, by changing the lengths L ₆ and L ₇ of the magnetic poles 812 and 822 in the ion beam traveling direction Z as described above, the ion beam 50 is made stronger toward the outer side from the center 804. Since it can be bent, the divergence of the ion beam 50 can be well compensated (cancelled) and collimated. That is, the ion beam 50 that diverges in the Y direction can be derived as a substantially parallel beam.

How much the lengths L ₆ and L ₇ of the magnetic poles 812 and 822 in the ion beam traveling direction Z are changed may be determined according to the degree of divergence of the incident ion beam 50 or the like. That is, when the ion beam 50 having a large divergence is handled, the changes in the lengths L ₆ and L ₇ may be increased. When the ion beam 50 having a small divergence is handled, the changes in the lengths L ₆ and L ₇ are reduced. good.

  The ion beam 50 that is substantially parallel in the Y direction can be incident on the deflection electromagnet 800 to derive the ion beam 50 that is focused in the Y direction. Since the ion beam 50 has the property of diverging due to the space charge effect, the ion beam 50 having a particularly low energy and a large beam current has a strong property. For example, the focused ion beam 50 is taken out from the deflection electromagnet 800. The ion beam 50 incident on the substrate 60 can be made into a substantially parallel beam by balancing (cancelling) the divergence due to the space charge effect between the deflection electromagnet 800 and the substrate 60.

52. By connecting the DC power supplies 840 and 842 in the reverse direction, the currents flowing in the coils 834 to 837 are reversed from those in the above example, and the magnetic fields B ₁ and B ₁ as shown in FIG. The direction of ₂ may be reversed from the case of the example of FIGS. However, the directions of the magnetic fields B ₁ and B ₂ are still opposite to each other.

In the case of the example of FIG. 52, Lorentz forces F ₁ and F ₂ received by the ion beam 50 passing through the gaps 816 and 826 are outward. Accordingly, the ion beam 50 is expanded. Also in this example, the ion beam 50 is more strongly bent by passing between the magnetic poles 812 and 822 longer (longer distance) as it is further away from the center 804 of the beam path 802 in the Y direction. Thereby, the orbital state of the ion beam 50 in the Y direction can be controlled.

  For example, focusing on the Y direction, when the ion beam 50 is focused (squeezed) in the Y direction by passing through another device, for example, the focusing angle is generally shown in FIG. 52, for example. Thus, it is small in the vicinity of the center 804 in the Y direction, and increases as it moves away from the center 804. This is because the focus is larger at the end.

On the other hand, by changing the lengths L ₆ and L ₇ of the magnetic poles 812 and 822 in the ion beam traveling direction Z as described above, the ion beam 50 is made stronger toward the outer side from the center 804. Since it can be bent, the above focusing of the ion beam 50 can be well compensated (cancelled) and collimated. That is, the ion beam 50 focused in the Y direction can be derived as a substantially parallel beam.

How much the lengths L ₆ and L ₇ of the magnetic poles 812 and 822 in the ion beam traveling direction Z are changed may be determined according to the degree of focusing of the incident ion beam 50 or the like. That is, when the ion beam 50 with a large focus is handled, the lengths L ₆ and L ₇ may be increased. When the ion beam 50 with a small focus is handled, the lengths L ₆ and L ₇ are decreased. good.

The ion beam 50 that diverges in the Y direction can be derived by making the ion beam 50 substantially parallel in the Y direction incident on the deflection electromagnet 800. For example, a beam concentrator can be provided on the downstream side of the deflection electromagnet 800, and the ion beam 50 can be collimated by combining divergence by the former and focusing by the latter. By doing so, the dimension W _Y in the Y direction of the ion beam 50 can be further increased.

  The deflection electromagnet 800 has a feature that in any of the above examples, an undesired lens action is less likely to appear in the X direction compared to the case where an electrostatic field is used.

  The deflection electromagnet 800 further includes a back surface in the X direction of one of the magnetic poles 812 (left side in FIG. 50, the same applies hereinafter) constituting the first magnetic pole pair 810 (that is, the surface opposite to the gap 816, the same applies hereinafter). A first yoke 830 that is magnetically connected to the back surface in the X direction of one magnetic pole 822 that is on the same side in the X direction as the magnetic pole 812 and constitutes the second magnetic pole pair 820, and a second magnetic pole pair 820 The other magnetic pole 812 in the X direction in the X direction and the other magnetic pole 812 in the X direction in the X direction and the other magnetic pole 812 in the X direction in the X direction. And a second yoke 832 magnetically connecting the back surface.

As a result, the first magnetic pole pair 810, the second magnetic pole pair 820, the first yoke 830, and the second yoke 832 form a loop-like magnetic circuit, and the magnetic flux forms a loop (see magnetic fields B _{1 to} B ₄ ). The magnetic field B ₁ and B ₂ can be efficiently generated in the gap 816 between the first magnetic pole pair 810 and the gap 826 between the second magnetic pole pair 820 that can reduce the leakage magnetic field to the outside. be able to.

  FIG. 53 is a front view showing another example of the deflection electromagnet together with the power source. FIG. 54 is a side view taken along line NN in FIG. 53, and shows an example in which a divergent beam is converted into a parallel beam. Portions that are the same as or correspond to those in the examples shown in FIGS. 50 to 52 are denoted by the same reference numerals, and differences from the examples will be mainly described below.

In this deflection electromagnet 800, as shown in FIG. 54, the lengths L ₆ and L ₇ in the ion beam traveling direction Z of the magnetic poles 812 and 822 constituting the first magnetic pole pair 810 and the second magnetic pole pair 820 are respectively set. , Substantially constant in the Y direction. In addition, it is preferable that the lengths L ₆ and L ₇ are substantially the same as each other, and this is the case in this example.

Instead, as shown in FIG. 53, the gap length G ₁ between the first magnetic pole pair 810 and the gap length G ₂ between the second magnetic pole pair 820 are respectively outside the center 804 of the beam path 802 in the Y direction ( Smaller as you move away (up and down). The gap 816 between the first magnetic pole pair 810 and the gap 826 between the second magnetic pole pair 820 are substantially in the Y direction with respect to a symmetry plane 806 passing through the center 804 in the Y direction of the beam path 802 and parallel to the XZ plane. It is preferable to use a plane-symmetrical shape, and in this example, this is the case.

If the gap lengths G ₁ and G ₂ are changed in the Y direction as described above, the magnetic flux density is small near the center 804 of the beam path 802, and the magnetic flux density increases as the distance from the center 804 increases. The ion beam 50 is bent more strongly in the Y direction as it is away from the center 804 of the beam path 802. As a result, the orbital state of the ion beam 50 in the Y direction can be controlled as in the previous example.

  For example, as in the example shown in FIG. 54, the diverging incident ion beam 50 can be derived as a substantially parallel beam. FIG. 54 corresponds to FIG. The ion beam 50 that is substantially parallel in the Y direction can be incident on the deflection electromagnet 800 to derive the ion beam 50 that is focused in the Y direction. The purpose and effect of doing so are as described above.

The currents flowing through the coils 834 to 837 may be reversed in the direction of the above example, and the directions of the magnetic fields B ₁ and B ₂ may be reversed as in the example of FIG. 54 as in the example shown in FIG. . However, the magnetic fields B ₁ and B ₂ are still opposite to each other. FIG. 55 corresponds to FIG.

  In the case of the example of FIG. 55, the incident ion beam 50 focused in the Y direction can be derived as a substantially parallel beam. The ion beam 50 that diverges in the Y direction can be derived by making the ion beam 50 substantially parallel in the Y direction incident on the deflection electromagnet 800. The purpose and effect of doing so are as described above.

How much the gap lengths G ₁ and G ₂ are changed in the Y direction may be determined according to the degree of divergence (or focusing) of the incident ion beam. That is, when the ion beam 50 having a large divergence (or focusing) is handled, the change in the gap lengths G ₁ and G ₂ may be increased, and when the ion beam 50 having a small divergence (or focusing) is handled, the gap length G ₁ , it may be smaller change in G _2.

  By providing the above-described deflecting electromagnet 800 in the ion implantation apparatus shown in FIG. 1, the parallelism in the Y direction of the ion beam 50 when entering the substrate 60 can be increased by the above-described action. As a result, ion implantation with good uniformity can be performed on the substrate 60.

  When the trajectory is changed by accelerating / decelerating the ion beam as in an electric field lens, particles (for example, neutral particles) having energy different from the energy of the incident ion beam by the amount of the accelerated / decelerated energy are generated. The deflection electromagnet 800 bends the trajectory of the ion beam by a magnetic field, and accelerates or decelerates the ion beam like an electric field lens. As a result, the trajectory is not changed, and energy contamination is not generated. Therefore, the deflection electromagnet 800 may be provided between the accelerator / decelerator 400 and the injection position. You may arrange | position close to the board | substrate 60. FIG. That is, according to the deflection electromagnet 800, energy contamination is not generated, so that the parallelism of the ion beam 50 can be increased near the substrate 60. Therefore, the parallelism of the ion beam 50 when entering the substrate 60 can be more reliably increased.

1 is a schematic plan view showing an embodiment of an ion implantation apparatus according to the present invention. It is a schematic perspective view which shows an example of a ribbon-shaped ion beam partially. It is a figure which shows the example of the relationship of the dimension in the Y direction of an ion beam and a board | substrate. It is a top view which shows an example of the analysis electromagnet shown in FIG. FIG. 5 is a cross-sectional view taken along line AA in FIG. 4. It is a perspective view which shows the analysis electromagnet shown in FIG. 4 except a vacuum vessel. It is a perspective view which shows the coil of the analysis electromagnet shown in FIG. FIG. 8 is a perspective view showing a first inner coil and a second inner coil shown in FIG. 7. It is the schematic which expands and shows the cross section of a 1st inner side coil and a 1st outer side coil along line DD in FIG. It is sectional drawing which decomposes | disassembles and shows the 1st inner side coil and uppermost 1st outer side coil which were shown in FIG. It is a schematic plan view which shows a mode that the conductor sheet shown in FIG. 10 is wound. It is a perspective view which shows the 1st inner side coil shown in FIG. It is a figure which shows an example of the power supply structure for the coils of the analysis electromagnet shown in FIG. It is a perspective view which shows an example of the laminated coils used as the origin of the 1st inner side coil, the 1st outer side coil, etc. which were shown in FIG. It is a figure which decomposes | disassembles and shows the cross section of an inner side coil and an outer side coil along line FF in FIG. It is a top view which shows an example of a mode that a prepreg sheet is wound using a type | mold. It is a top view which shows an example of a mode that an insulating sheet and a conductor sheet are wound using a type | mold. It is a top view which shows an example of the laminated coil after winding using the type | mold. It is sectional drawing which shows an example which attached the cooling plate to the 1st inner side coil and the 1st outer side coil. It is a figure which shows the example of the ion beam which has a normal form immediately after radiate | emitting from an analysis electromagnet. It is a figure which shows an example of the ion beam which has a distorted form immediately after radiate | emitting from an analysis electromagnet. It is a perspective view which shows the other example of the coil of an analysis electromagnet. It is a figure which decomposes | disassembles and shows the cross section of a coil along line JJ in FIG. It is sectional drawing which shows the other example of an analysis electromagnet, and is equivalent to FIG. It is sectional drawing which shows the other example of an analysis electromagnet, and is equivalent to FIG. It is sectional drawing which shows the other example of an analysis electromagnet, and is equivalent to FIG. It is a front view which shows an example of the analysis slit shown in FIG. It is a figure which shows an example around the focus correction lens shown in FIG. It is a perspective view which shows an example of a focus correction lens. It is a figure which shows the example which correct | amended the focus position of the ion beam with the focus correction lens provided in the upstream of the analysis electromagnet. It is a figure which shows the example which correct | amended the focus position of the ion beam with the focus correction lens provided in the downstream of the analysis electromagnet. It is a figure which shows the example which correct | amended the focus position of the ion beam with the focus correction lens provided in the upstream and downstream of the analysis electromagnet. It is the schematic which shows an example of beam current distribution in the position of 640 mm from the analysis electromagnet exit in case the space charge of an ion beam is completely neutralized. It is the schematic which shows an example of beam current distribution in the position of 640 mm from the analysis electromagnet exit when the space charge of an ion beam is not completely neutralized. An example of beam current distribution at a position of 640 mm from the outlet of the analyzing electromagnet when the ion beam focal position is corrected by the upstream focus correction lens when the space charge of the ion beam is not completely neutralized. FIG. It is the schematic which shows an example of the relationship between the direct current voltage applied to the intermediate electrode of a focus correction lens, and the beam current measured with a 1st beam current measuring device. It is the schematic which shows the other example of the relationship between the direct current voltage applied to the intermediate electrode of a focus correction lens, and the beam current measured with a 1st beam current measuring device. It is a figure which shows partially an example around the 2nd beam current measuring device which measures the beam current which flows into an analysis slit. It is the schematic which shows an example of the relationship between the direct current voltage applied to the intermediate electrode of a focus correction lens, and the beam current measured with a 2nd beam current measuring device. It is a cross-sectional view which shows an example of the accelerator / decelerator shown in FIG. It is a perspective view which expands and shows the track control lens shown in FIG. 1 with a power supply. It is a figure which shows an example of distribution of the equipotential line between the electrodes of the track control lens shown in FIG. FIG. 42 is a diagram illustrating an example in which an incident ion beam that diverges in the Y direction is derived as a parallel beam in the trajectory control lens illustrated in FIG. 41. FIG. 42 is a diagram showing an example in which an incident ion beam parallel in the Y direction is derived as a focused beam in the trajectory control lens shown in FIG. 41. FIG. 42 is a diagram showing an example in which an incident ion beam parallel in the Y direction is derived as a divergent beam in the trajectory control lens shown in FIG. 41. It is a perspective view which shows the other example of a track control lens with a power supply. FIG. 47 is a diagram illustrating an example in which an incident ion beam diverging in the Y direction is derived as a parallel beam in the trajectory control lens illustrated in FIG. 46. It is a top view which shows an example of a uniform lens. FIG. 49 is a diagram showing an example of a power supply when the uniformizing lens shown in FIG. 48 is viewed in the ion beam traveling direction. It is a front view which shows an example of a deflection | deviation electromagnet with a power supply. It is a side view in alignment with line MM of FIG. 50, and shows the example in the case of making a divergent beam into a parallel beam. It is a side view in alignment with line MM of FIG. 50, and shows the example in the case of making a focused beam into a parallel beam. It is a front view which shows the other example of a deflection electromagnet with a power supply. FIG. 54 is a side view taken along line NN in FIG. 53 and shows an example in which a diverging beam is converted into a parallel beam. It is a side view in alignment with line NN of FIG. 53, and shows the example in the case of making a focused beam into a parallel beam. It is a perspective view which shows an example of the conventional analysis electromagnet, and in order to make the shape of a coil easy to understand, the yoke is shown with the dashed-two dotted line.

Explanation of symbols

50 Ion beam 56 Focus 60 Substrate 70 Analysis slit 100 Ion source 200 Analysis electromagnet 206 First inner coil 208 Main body part 210 Transition part 212 Second inner coil 214 Main body part 216 Transition part 218 First outer coil 220 Main body part 222 Transition part 224 Second outer coil 226 Main body portion 228 Crossing portion 230 Yoke 232 Magnetic pole 261 to 263 Laminated insulator 266, 267 Insulating sheet 268, 269 Conductor sheet 272-281 Notch portion 282 Vertical portion 284 Horizontal portion 290 Laminated coil 320 Coil 326 First Coil 328 Second coil 330 Inner coil 500 Substrate driving device 600 Focus correction lens 602 Entrance electrode 604 Intermediate electrode 606 Exit electrode 610 Focus correction lens 612 Entrance electrode 614 Intermediate electrode 616 Exit electrode 70 a, 700b orbit control lens 702 entrance electrode 704 intermediate electrode 706 exit electrode 750 uniform lens 752 electrode 800 bending magnet 810 first pole pair 812 pole 816 gap 820 second pole pair 822 pole 826 Gap 834-837 coil

Claims (7)

(A) If the traveling direction of the ion beam is the Z direction, and two directions substantially orthogonal to each other in a plane substantially orthogonal to the Z direction are the X direction and the Y direction, the direction of the Y direction is larger than the dimension of the X direction. An ion implantation apparatus that transports a ribbon-shaped ion beam having a large size and irradiates it with a substrate to perform ion implantation,
An ion source for generating the ribbon-like ion beam having a dimension in the Y direction larger than a dimension in the Y direction of the substrate;
Analyzing the momentum by bending the ion beam from the ion source in the X direction; and an analyzing electromagnet for forming a focal point of the ion beam having a desired momentum on the downstream side;
An analysis slit that is provided near the focal point of the ion beam from the analysis electromagnet, and performs momentum analysis of the ion beam in cooperation with the analysis electromagnet;
Correction that is provided between at least one of the ion source and the analysis electromagnet and between the analysis electromagnet and the analysis slit, and adjusts the position of the focal point of the ion beam to the position of the analysis slit by an electrostatic field. A focus correction lens that performs
An accelerator / decelerator that bends the ion beam that has passed through the analysis slit in the X direction by an electrostatic field and accelerates or decelerates the ion beam by the electrostatic field;
A substrate driving device that moves the substrate in a direction intersecting the main surface of the ion beam at an implantation position where the ion beam that has passed through the accelerator is incident on the substrate ;
An inlet electrode provided between the analysis electromagnet and the accelerometer, which bends the ion beam in the Y direction by an electrostatic field and is arranged with a gap in the ion beam traveling direction; A trajectory control lens having an electrode and an exit electrode ,
(B) The analysis electromagnet
A pair of main body portions that are opposed to each other in the X direction across the beam path that is the path of the ion beam and that cover approximately half or more of one side of the Y direction of the ion beam, and along the Z direction of both main body portions A saddle-shaped coil having a pair of crossing portions that are connected between end portions in the direction so as to avoid the beam path, and bends the ion beam in the X direction in cooperation with the second coil. A first coil for generating a magnetic field;
A pair of main body portions that are opposed to each other in the X direction across the beam path and cover approximately half or more of the other side of the ion beam in the Y direction, and between the end portions in the direction along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that are connected to each other while avoiding the beam path, and is disposed so as to overlap with the first coil in the Y direction, and cooperates with the first coil. A second coil that acts to generate a magnetic field that bends the ion beam in the X direction;
A yoke that collectively surrounds the outside of the main body of the first coil and the second coil,
(C) The upper yoke constituting the yoke is made removable.
( D ) and the first coil and the second coil of the analyzing electromagnet are each wound a plurality of times by laminating an insulating sheet and a conductor sheet each having a principal surface along the Y direction on the outer peripheral surface of the laminated insulator. laminating Te, more fan-shaped cylindrical stacked coil forming a laminated insulator on the outer peripheral surface thereof has a structure in which a cutout portion while leaving the body portion and connecting portions,
(E) A pair of the entrance electrode, the intermediate electrode, and the exit electrode of the trajectory control lens, which are arranged opposite to each other in the X direction across a gap through which the ion beam passes and are electrically connected to each other. Electrode
(F) The intermediate electrode of the trajectory control lens has convex surfaces curved in the Y direction on the upstream and downstream surfaces in the ion beam traveling direction,
(G) The entrance electrode and the exit electrode of the trajectory control lens each have a concave surface along the convex surface on a surface facing the convex surface of the intermediate electrode,
(H) The entrance electrode and the exit electrode of the trajectory control lens are kept at the same potential, and the intermediate electrode has a potential different from that of the entrance electrode and the exit electrode. An ion implantation apparatus characterized by being maintained at a potential that makes a desired orbital state in a direction . (A) If the traveling direction of the ion beam is the Z direction, and two directions substantially orthogonal to each other in a plane substantially orthogonal to the Z direction are the X direction and the Y direction, An ion implantation apparatus that transports a ribbon-shaped ion beam having a large size and irradiates it with a substrate to perform ion implantation,
An ion source for generating the ribbon-like ion beam having a dimension in the Y direction larger than a dimension in the Y direction of the substrate;
Analyzing the momentum by bending the ion beam from the ion source in the X direction; and an analyzing electromagnet for forming a focal point of the ion beam having a desired momentum on the downstream side;
An analysis slit that is provided near the focal point of the ion beam from the analysis electromagnet, and performs momentum analysis of the ion beam in cooperation with the analysis electromagnet;
Correction that is provided between at least one of the ion source and the analysis electromagnet and between the analysis electromagnet and the analysis slit, and adjusts the position of the focal point of the ion beam to the position of the analysis slit by an electrostatic field. A focus correction lens that performs
An accelerator / decelerator that bends the ion beam that has passed through the analysis slit in the X direction by an electrostatic field and accelerates or decelerates the ion beam by the electrostatic field;
A substrate driving device that moves the substrate in a direction intersecting the main surface of the ion beam at an implantation position where the ion beam that has passed through the accelerator is incident on the substrate ;
An inlet electrode provided between the analysis electromagnet and the accelerometer, which bends the ion beam in the Y direction by an electrostatic field and is arranged with a gap in the ion beam traveling direction; A trajectory control lens having an electrode and an exit electrode ,
(B) The analysis electromagnet
A pair of main body portions that are opposed to each other in the X direction across the beam path that is the path of the ion beam and that cover approximately half or more of one side of the Y direction of the ion beam, and along the Z direction of both main body portions A saddle-shaped coil having a pair of crossing portions that are connected between end portions in the direction so as to avoid the beam path, and bends the ion beam in the X direction in cooperation with the second coil. A first coil for generating a magnetic field;
A pair of main body portions that are opposed to each other in the X direction across the beam path and cover approximately half or more of the other side of the ion beam in the Y direction, and between the end portions in the direction along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that are connected to each other while avoiding the beam path, and is disposed so as to overlap with the first coil in the Y direction, and cooperates with the first coil. A second coil that acts to generate a magnetic field that bends the ion beam in the X direction;
A yoke that collectively surrounds the outside of the main body of the first coil and the second coil,
(C) The upper yoke constituting the yoke is made removable.
( D ) and the first coil and the second coil of the analyzing electromagnet are each wound a plurality of times by laminating an insulating sheet and a conductor sheet each having a principal surface along the Y direction on the outer peripheral surface of the laminated insulator. laminating Te, more fan-shaped cylindrical stacked coil forming a laminated insulator on the outer peripheral surface thereof has a structure in which a cutout portion while leaving the body portion and connecting portions,
(E) A pair of the entrance electrode, the intermediate electrode, and the exit electrode of the trajectory control lens, which are arranged opposite to each other in the X direction across a gap through which the ion beam passes and are electrically connected to each other. Electrode
(F) The intermediate electrode of the trajectory control lens has concave surfaces curved in the Y direction on the upstream and downstream surfaces in the ion beam traveling direction,
(G) Each of the entrance electrode and the exit electrode of the trajectory control lens has a convex surface along the concave surface on the surface facing the concave surface of the intermediate electrode,
(H) The entrance electrode and the exit electrode of the trajectory control lens are kept at the same potential, and the intermediate electrode has a potential different from that of the entrance electrode and the exit electrode. An ion implantation apparatus characterized by being maintained at a potential that makes a desired orbital state in a direction . (A) If the traveling direction of the ion beam is the Z direction, and two directions substantially orthogonal to each other in a plane substantially orthogonal to the Z direction are the X direction and the Y direction, An ion implantation apparatus that transports a ribbon-shaped ion beam having a large size and irradiates it with a substrate to perform ion implantation,
An ion source for generating the ribbon-like ion beam having a dimension in the Y direction larger than a dimension in the Y direction of the substrate;
Analyzing the momentum by bending the ion beam from the ion source in the X direction; and an analyzing electromagnet for forming a focal point of the ion beam having a desired momentum on the downstream side;
An analysis slit that is provided near the focal point of the ion beam from the analysis electromagnet, and performs momentum analysis of the ion beam in cooperation with the analysis electromagnet;
Correction that is provided between at least one of the ion source and the analysis electromagnet and between the analysis electromagnet and the analysis slit, and adjusts the position of the focal point of the ion beam to the position of the analysis slit by an electrostatic field. A focus correction lens that performs
An accelerator / decelerator that bends the ion beam that has passed through the analysis slit in the X direction by an electrostatic field and accelerates or decelerates the ion beam by the electrostatic field;
A substrate driving device that moves the substrate in a direction intersecting the main surface of the ion beam at an implantation position where the ion beam that has passed through the accelerator is incident on the substrate ;
An inlet electrode provided between the analysis electromagnet and the accelerometer, which bends the ion beam in the Y direction by an electrostatic field and is arranged with a gap in the ion beam traveling direction; A trajectory control lens having an electrode and an exit electrode ,
(B) The analysis electromagnet
A pair of main body portions that are opposed to each other in the X direction across the beam path that is the path of the ion beam and that cover approximately half or more of one side of the Y direction of the ion beam, and along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that connect the end portions in the direction avoiding the beam path, and in cooperation with the second inner coil, the ion beam is moved in the X direction. A first inner coil that generates a main magnetic field to be bent;
A pair of main body portions that are opposed to each other in the X direction across the beam path and cover approximately half or more of the other side of the ion beam in the Y direction, and between the end portions in the direction along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that are connected to each other while avoiding the beam path, and is arranged so as to overlap with the first inner coil in the Y direction. In cooperation with the second inner coil for generating a main magnetic field that bends the ion beam in the X direction;
A pair of main body portions outside the first inner coil and facing each other in the X direction across the beam path and the ends of the two main body portions in the direction along the Z direction are connected to each other while avoiding the beam path. One or more first outer coils for generating a sub-magnetic field for assisting or correcting the main magnetic field, wherein the coil is a saddle-shaped coil having a pair of crossing portions
A pair of main body portions outside the second inner coil and facing each other in the X direction across the beam path, and the ends of the two main body portions in the direction along the Z direction are connected to each other while avoiding the beam path. A saddle-shaped coil having a pair of crossing portions that are arranged to overlap the first outer coil in the Y direction and generate a sub-magnetic field for assisting or correcting the main magnetic field One or more second outer coils;
A yoke that collectively surrounds the outside of the main body of the first inner coil, the second inner coil, the first outer coil, and the second outer coil;
(C) The upper yoke constituting the yoke is made removable.
( D ) And the first inner coil and the first outer coil of the analyzing electromagnet are wound multiple times on the outer peripheral surface of the laminated insulator with the main surface superposed on the insulating sheet and the conductor sheet along the Y direction. A laminated insulator is formed on the outer peripheral surface thereof, and the outer peripheral surface is laminated by winding a plurality of layers of an insulating sheet and a conductor sheet whose main surface is along the Y direction. In the fan-shaped cylindrical laminated coil in which the laminated insulator is formed, the cutout part is provided leaving the main body part and the transition part,
( E ) The second inner coil and the second outer coil of the analysis electromagnet are obtained by winding a plurality of turns on an outer peripheral surface of a laminated insulator, with an insulating sheet and a conductor sheet superposed on each other along the Y direction. Laminate and form a laminated insulator on the outer peripheral surface, and laminate the outer peripheral surface by winding a plurality of layers of an insulating sheet and a conductor sheet whose main surface is along the Y direction. the fan-shaped cylindrical stacked coil forming a laminated insulation, has a structure in which a cutout portion while leaving the body portion and connecting portions,
(F) A pair of the entrance electrode, the intermediate electrode, and the exit electrode of the trajectory control lens, which are arranged opposite to each other in the X direction across a gap through which the ion beam passes and are electrically connected to each other. Electrode
(G) The intermediate electrode of the trajectory control lens has convex surfaces curved in the Y direction on the upstream and downstream surfaces in the ion beam traveling direction,
(H) The entrance electrode and the exit electrode of the trajectory control lens each have a concave surface along the convex surface on a surface facing the convex surface of the intermediate electrode,
(I) In addition, the entrance electrode and the exit electrode of the trajectory control lens are kept at the same potential, and the intermediate electrode has a potential different from that of the entrance electrode and the exit electrode, and Y of the ion beam derived from the trajectory control lens An ion implantation apparatus characterized by being maintained at a potential that makes a desired orbital state in a direction . (A) If the traveling direction of the ion beam is the Z direction, and two directions substantially orthogonal to each other in a plane substantially orthogonal to the Z direction are the X direction and the Y direction, An ion implantation apparatus that transports a ribbon-shaped ion beam having a large size and irradiates it with a substrate to perform ion implantation,
An ion source for generating the ribbon-like ion beam having a dimension in the Y direction larger than a dimension in the Y direction of the substrate;
Analyzing the momentum by bending the ion beam from the ion source in the X direction; and an analyzing electromagnet for forming a focal point of the ion beam having a desired momentum on the downstream side;
An analysis slit that is provided near the focal point of the ion beam from the analysis electromagnet, and performs momentum analysis of the ion beam in cooperation with the analysis electromagnet;
Correction that is provided between at least one of the ion source and the analysis electromagnet and between the analysis electromagnet and the analysis slit, and adjusts the position of the focal point of the ion beam to the position of the analysis slit by an electrostatic field. A focus correction lens that performs
An accelerator / decelerator that bends the ion beam that has passed through the analysis slit in the X direction by an electrostatic field and accelerates or decelerates the ion beam by the electrostatic field;
A substrate driving device that moves the substrate in a direction intersecting the main surface of the ion beam at an implantation position where the ion beam that has passed through the accelerator is incident on the substrate ;
An inlet electrode provided between the analysis electromagnet and the accelerometer, which bends the ion beam in the Y direction by an electrostatic field and is arranged with a gap in the ion beam traveling direction; A trajectory control lens having an electrode and an exit electrode ,
(B) The analysis electromagnet
A pair of main body portions that are opposed to each other in the X direction across the beam path that is the path of the ion beam and that cover approximately half or more of one side of the Y direction of the ion beam, and along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that connect the end portions in the direction avoiding the beam path, and in cooperation with the second inner coil, the ion beam is moved in the X direction. A first inner coil that generates a main magnetic field to be bent;
A pair of main body portions that are opposed to each other in the X direction across the beam path and cover approximately half or more of the other side of the ion beam in the Y direction, and between the end portions in the direction along the Z direction of both main body portions A saddle-shaped coil having a pair of connecting portions that are connected to each other while avoiding the beam path, and is arranged so as to overlap with the first inner coil in the Y direction. In cooperation with the second inner coil for generating a main magnetic field that bends the ion beam in the X direction;
A pair of main body portions outside the first inner coil and facing each other in the X direction across the beam path and the ends of the two main body portions in the direction along the Z direction are connected to each other while avoiding the beam path. One or more first outer coils for generating a sub-magnetic field for assisting or correcting the main magnetic field, wherein the coil is a saddle-shaped coil having a pair of crossing portions
A pair of main body portions outside the second inner coil and facing each other in the X direction across the beam path, and the ends of the two main body portions in the direction along the Z direction are connected to each other while avoiding the beam path. A saddle-shaped coil having a pair of crossing portions that are arranged to overlap the first outer coil in the Y direction and generate a sub-magnetic field for assisting or correcting the main magnetic field One or more second outer coils;
A yoke that collectively surrounds the outside of the main body of the first inner coil, the second inner coil, the first outer coil, and the second outer coil;
(C) The upper yoke constituting the yoke is made removable.
( D ) And the first inner coil and the first outer coil of the analyzing electromagnet are wound multiple times on the outer peripheral surface of the laminated insulator with the main surface superposed on the insulating sheet and the conductor sheet along the Y direction. A laminated insulator is formed on the outer peripheral surface thereof, and the outer peripheral surface is laminated by winding a plurality of layers of an insulating sheet and a conductor sheet whose main surface is along the Y direction. In the fan-shaped cylindrical laminated coil in which the laminated insulator is formed, the cutout part is provided leaving the main body part and the transition part,
( E ) The second inner coil and the second outer coil of the analysis electromagnet are obtained by winding a plurality of turns on an outer peripheral surface of a laminated insulator, with an insulating sheet and a conductor sheet superposed on each other along the Y direction. Laminate and form a laminated insulator on the outer peripheral surface, and laminate the outer peripheral surface by winding a plurality of layers of an insulating sheet and a conductor sheet whose main surface is along the Y direction. the fan-shaped cylindrical stacked coil forming a laminated insulation, has a structure in which a cutout portion while leaving the body portion and connecting portions,
(F) A pair of the entrance electrode, the intermediate electrode, and the exit electrode of the trajectory control lens, which are arranged opposite to each other in the X direction across a gap through which the ion beam passes and are electrically connected to each other. Electrode
(G) The intermediate electrode of the trajectory control lens has concave surfaces curved in the Y direction on the upstream and downstream surfaces in the ion beam traveling direction,
(H) The entrance electrode and the exit electrode of the trajectory control lens each have a convex surface along the concave surface on a surface facing the concave surface of the intermediate electrode,
(I) In addition, the entrance electrode and the exit electrode of the trajectory control lens are kept at the same potential, and the intermediate electrode has a potential different from that of the entrance electrode and the exit electrode, and Y of the ion beam derived from the trajectory control lens An ion implantation apparatus characterized by being maintained at a potential that makes a desired orbital state in a direction .   5. The ion implantation according to claim 1, wherein the analysis electromagnet further includes a pair of magnetic poles protruding inward from the yoke so as to face each other in the Y direction across the beam path. apparatus. The focus correction lens has an entrance electrode, an intermediate electrode, and an exit electrode arranged with a gap in the ion beam traveling direction,
The entrance electrode, the intermediate electrode, and the exit electrode of the focus correction lens are each a pair of electrodes that are disposed opposite to each other in the X direction with a gap through which the ion beam passes and are electrically connected to each other. Have
In addition, the entrance electrode and the exit electrode of the focus correction lens are kept at the same potential, and the intermediate electrode is at a different potential from the entrance electrode and the exit electrode, and the focus position of the ion beam is adjusted to the position of the analysis slit. The ion implantation apparatus according to claim 1, wherein the ion implantation apparatus is maintained at a potential.   The accelerator / decelerator has first to third electrodes arranged in the order of the first electrode, the second electrode, and the third electrode from the upstream side in the traveling direction of the ion beam, The ion beam is accelerated or decelerated in two stages between the first electrode and the second electrode and between the second electrode and the third electrode, and the second electrode is , Divided into two electrode bodies that are opposed to each other in the X direction across the path of the ion beam and are applied with different electric potentials to deflect the ion beam in the X direction, and a third electrode, The ion implantation apparatus according to claim 1, wherein the ion implantation apparatus is arranged along a trajectory of an ion beam having a specific energy after the deflection.

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