JP5648942B2 - Magnet for ion beam irradiation apparatus provided with protective member covering a plurality of magnetic field concentrating members - Google Patents

Description

  The present invention relates to a configuration for confining electrons in a magnet that is used in an ion beam irradiation apparatus and deflects, scans, converges, or diverges the ion beam.

  In recent years, improvement in productivity of ion beam irradiation apparatuses has been demanded. As one of the means, attention has been paid to a technique for improving the transport efficiency of a low-energy ion beam having a positive charge. More specifically, there is a technique for suppressing the spread due to the space charge effect of the ion beam passing through the magnet by confining electrons inside the magnet used in the ion beam irradiation apparatus.

  An example of this technique is disclosed in Patent Document 1. Patent Document 1 discloses an analysis magnet including a plurality of magnetic field concentrating members on opposing surfaces of magnetic pole members arranged to face each other.

  The plurality of magnetic field concentrating members include a collar portion and a groove, and generate a magnetic mirror effect inside the analysis magnet. As a result, when an electron moving in the direction of the magnetic field generated between the magnetic pole members approaches one magnetic pole member, it is affected by the concentrated magnetic field formed by the magnetic field concentration member, and the other magnetic pole member Reflected to the side. Thereafter, the reflected electrons again move toward the other magnetic pole member along the direction of the magnetic field generated between the magnetic pole members. And when approaching the other magnetic pole member, it is reflected toward the opposite direction again by the concentrated magnetic field of the magnetic field concentration member. In this way, electrons are confined inside the magnet by combining the movement of electrons between the magnetic pole members and the reflection of electrons by the magnetic field concentration member.

JP-T-2008-521208 (paragraphs 0020-0022, FIGS. 2 to 6)

  However, even if the technology described in Patent Document 1 is used to successfully confine electrons inside the magnet, it cannot be said that the productivity of the ion beam irradiation apparatus alone can be improved.

  Usually, the gap between the magnetic pole members through which the ion beam passes is designed to be slightly larger than the size of the ion beam in consideration of the size of the ion beam passing therethrough. This is to generate a sufficiently uniform magnetic field over the entire area of the ion beam.

  The ion beam has the property of diverging due to the space charge effect. Therefore, even if the divergence of the ion beam is suppressed by electrons inside the magnet, it is difficult to completely suppress the divergence, and it is considered that the divergence slightly occurs. The ion beam appears to travel straight as a whole, but locally includes beam components in various directions. For this reason, it is conceivable that the ion beam passing through the gap between the magnetic pole members collides with the magnetic field concentration member provided on the magnetic pole.

  When the ion beam collides with the magnetic field concentration member and the magnetic field concentration member is sputtered, the shape of the magnetic field concentration member is deformed. As a result, a sufficient concentrated magnetic field cannot be generated. As a result, the effect of confining electrons is hindered. In such a case, in order to maintain the electron confinement effect, the deformed magnetic field concentrating member must be replaced with a new one. Since the ion beam irradiation apparatus is stopped during the exchange, the productivity of the ion beam irradiation apparatus is lowered.

  Furthermore, the magnetic field concentration member sputtered by the ion beam is scattered as particles. If metal is used for the magnetic field concentration member, part of the scattered magnetic field concentration member is mixed in the substrate irradiated with the ion beam, causing metal contamination that can be fatal for semiconductor device manufacturing. End up. If it becomes so, the defect rate of a semiconductor manufacturing element will rise and the productivity of an ion beam irradiation apparatus will fall.

  Accordingly, the present invention has been made to solve the above problems all at once, and is mainly intended to achieve confinement of electrons inside the magnet without impairing the productivity of the ion beam irradiation apparatus. It is to be an issue.

That is, the magnet according to the present invention is a magnet used in an ion beam irradiation apparatus, and a pair of magnetic poles arranged opposite each other so as to sandwich the ion beam inside the magnet, and the pair of magnetic poles facing each other. A plurality of magnetic field concentrating members that are provided on a surface and generate an electron confinement action between the magnetic poles, a protective member that covers at least the surfaces of the plurality of magnetic field concentrating members facing each other across the ion beam, and one end A holding member fixed to the magnetic pole, and the protection member is restricted from moving toward the ion beam in a direction perpendicular to the surface of the magnetic pole by the other end of the holding member. In this state, the magnetic poles are individually assembled to the magnetic poles constituting the pair of magnetic poles by sliding on the magnetic poles or the magnetic field concentrating members.

In such a case, since the magnetic field concentrating member is not directly sputtered by the ion beam, deformation of the magnetic field concentrating member due to sputtering can be prevented. In addition, since the magnetic field concentrating member is not deformed, the electron confinement function can be prevented from being lowered. As a result, the electron confinement function can be prevented from being lowered, so that it is not necessary to stop the apparatus by replacing the magnetic field concentrating member. Furthermore, even when a metal is used as the magnetic field concentrating member, the magnetic field concentrating member is not sputtered, so there is no concern about metal contamination. Therefore, it is possible to achieve the confinement of electrons inside the magnet without hindering the productivity of the ion beam irradiation apparatus. Furthermore, according to the configuration described above, since the protective member can be assembled to the magnetic pole by sliding the protective member using the holding member, the time required for the position adjustment operation of the protective member performed during the assembly can be shortened. .

  Moreover, the said protection member may be comprised from the some member.

  Usually, the planar shape of the magnetic pole is complicatedly curved along the trajectory of the designed ion beam passing between the magnetic poles. Therefore, when the protective member is slid and assembled with respect to the magnetic pole, depending on the shape of the magnetic pole and the protective member, it may not be possible to assemble the single protective member so as to cover the entire surface of the magnetic pole surface. is expected. In such a case, the protective member is matched to the shape of the magnetic pole, and is divided into a plurality of sizes that are easy to slide, and the divided protective members are individually slid and assembled to the magnetic pole. With such a configuration, assembly and removal operations are facilitated.

  You may comprise so that the said whole protection member may be accommodated in the space between the said magnetic pole or the said magnetic field concentration member, and the said other end part of the said holding member in the direction perpendicular | vertical to the surface of the said magnetic pole.

  On the other hand, the surface of the protective member facing the ion beam has a recess, and has a holding member whose one end is locked to the magnetic pole and the other end is in contact with the recess. A configuration may be adopted.

  In addition, in order to stably operate the ion beam irradiation apparatus for a long time, a protrusion is formed on the protective member, and when the surface of the magnetic pole facing the ion beam is used as a reference, the height of the protrusion is high. Is set so as to be gradually lowered along the design traveling direction of the ion beam passing between the magnetic poles, and the protrusion is positioned between the ion beam and the magnetic field concentration member. It is desirable.

  According to such a configuration, even when the ion beam irradiation apparatus is operated for a long time, the protective member located above the magnetic field concentration member is not easily consumed by sputtering. Therefore, the electron confinement effect inside the magnet can be maintained for a long time.

  According to the present invention configured as described above, it is possible to achieve the confinement of electrons inside the magnet without hindering the productivity of the ion beam irradiation apparatus.

It is a perspective view showing the magnet which concerns on one Example of this invention. The mode on the XY plane of the protection member concerning one example of the present invention is expressed. The mode on the XY plane of the protection member concerning another example of the present invention is expressed. The situation on the ZX plane of FIGS. 2 and 3 is shown. The mode on the XY plane of the protection member concerning other examples of the present invention is expressed. The aspect on the XY plane of the protection member which concerns on the further Example of this invention is represented. It is a principal part enlarged view of FIG. It is the schematic which shows that the magnetic pole plane is covered with the some protection member. It is the schematic showing the mode on the XY plane of FIG. FIG. 10 is a perspective view of FIG. 9. It is a perspective view showing a mode that the protection member was removed from FIG. It is another Example about a holding structure. A line segment AA shown in FIG. 12 represents a cross section of the structure when sheared along the Y direction. It is another Example about a holding structure.

  FIG. 1 is a perspective view showing an entire magnet according to an embodiment of the present invention. The X direction, Y direction, and Z direction shown in the figure are orthogonal to each other, and the design traveling direction of the ion beam incident on the magnet is the X direction.

  Based on FIG. 1, the structure of the whole magnet based on one Example of this invention is demonstrated. In FIG. 1, an ion beam 8 traveling along the X direction enters the magnet 1. The magnet 1 is provided with a pair of magnetic poles 2 so as to sandwich the ion beam 8 in the Y direction. For example, the magnetic pole 2 is attached to the magnet 1 using a bolt or the like.

  On the opposing surfaces of the pair of magnetic poles 2, that is, the surface of the magnetic pole 2 on the side facing the ion beam 8 passing between the pair of magnetic poles 2, electrons are transferred between the pair of magnetic poles 2 by a mirror magnetic field as in the conventional technique. A plurality of magnetic field concentrating members 3 for confinement are provided. The magnetic field concentrating member 3 is also attached to the magnetic pole 2 with a bolt or the like. In FIG. 1, in order to simplify the drawing, a plurality of magnetic field concentration members 3 are drawn as a single member. Further, in FIG. 1, the plurality of magnetic field concentrating members 3 are disposed only on a part of the surface of the magnetic pole 2 facing the ion beam, but may be disposed on the entire surface of the magnetic pole 2 facing the ion beam.

  Further, when the ion beam 8 passes between the pair of magnetic poles 2, the protection member 4 is provided so as to cover all the surfaces of the plurality of magnetic field concentration members 3 provided on the side facing the ion beam 8.

  By providing this protective member 4, it is possible to achieve the confinement of electrons inside the magnet without hindering the productivity of the ion beam irradiation apparatus.

  As the material of the protective member 4, carbon that is difficult to be sputtered by the ion beam 8 can be considered. Further, when the ion beam irradiation object is a silicon wafer, silicon may be used.

  In the magnet 1 of FIG. 1, the protection member 4 is assembled by sliding with respect to the magnetic pole 2. And in one Example in this invention, the groove | channel 5 is provided in the both sides | surfaces of the protection member 4 located in the Z direction of FIG.

  On both side surfaces of the magnetic pole 2 positioned in the Z direction, there are provided holding members 6 whose one end is fixed to the magnetic pole 2 by a stopper 7 such as a bolt. The other end of the holding member 6 is configured to be assembled to the magnetic pole 2 by sliding the protection member 4 in a state of being inserted into the groove 5 provided in the protection member 4. In the case of FIG. 1, the assembling is performed by sliding the protective member 4 in the direction opposite to the traveling direction of the ion beam.

  In addition, the groove | channel 5 provided in the side surface of the Z direction of the protection member 4 may be what kind of shape, as long as the protection member 4 can be assembled | attached by a slide. Further, in the example of FIG. 1, the groove 5 is provided only in part along the length direction on both side surfaces of the protection member 4, but the groove may be formed over the entire length in the length direction. .

  FIG. 2 illustrates a state on the XY plane of a protective member according to an embodiment of the present invention. In FIG. 2, the holding member 6 is omitted for easy understanding of the relationship between the magnetic pole 2, the magnetic field concentration member 3, and the protection member 4. Moreover, the magnetic pole drawn here is the magnetic pole 2 located in the Y direction lower side among a pair of magnetic poles arranged oppositely in the magnet shown in FIG. In the two magnetic poles 2 arranged opposite to each other, the same configuration may be used for the magnetic field concentrating member 3, the protective member 4, and the holding member 6 that holds the protective member 4 provided in each magnetic pole. In order to avoid redundant description, in the embodiment of the present invention, only one magnetic pole and each member provided thereon are described.

  The plurality of magnetic field concentrating members 3 are composed of a plurality of permanent magnets as shown in FIG. This is merely an example, and any other type that generates a concentrated magnetic field in addition to a permanent magnet may be used. Further, the plurality of magnetic field concentrating members 3 may be partially disposed on the magnetic pole surface as shown in FIG. 2, or when it is desired to more reliably confine electrons in the magnet, It may be placed across.

  The pair of magnetic poles 2 have a pair of polarities in order to generate a magnetic field between the magnetic poles in one direction. In FIG. 2, N poles are arranged as an example. And the polarity of the permanent magnet which comprises the some magnetic field concentration member 3 is arrange | positioned so that a magnetic pole side may be a south pole and the other side may be a north pole. If the polarity of the magnetic pole 2 is the S pole, the direction of the polarity of the permanent magnets constituting the plurality of magnetic field concentrating members 3 is opposite to that described above.

  The protective member 4 is provided so as to cover the upper surfaces (Y direction side) of the plurality of magnetic field concentration members 3 arranged on the magnetic pole surface. Grooves into which one end of the holding member shown in FIG. 1 is inserted are formed on two side surfaces intersecting the Z direction of the protection member 4. In this example, the protective member 4 covers only the upper surface of the magnetic field concentrating member 3, but the protective member 4 may also cover gaps between the plurality of magnetic field concentrating members 3 partially disposed on the surface of the magnetic pole 2. In the configuration shown in FIG. 2, the protection member 4 and the plurality of magnetic field concentration members 3 are configured as separate members, and an assembly operation and a removal operation are performed separately.

  As another example of the plurality of magnetic field concentrating members 3, it is conceivable to alternately arrange a material having a high magnetic permeability and a material having a low magnetic permeability. In this case, it is conceivable that a material having a high magnetic permeability is disposed at a location where the permanent magnets in FIG. 2 are disposed, and a material having a low magnetic permeability is disposed at a gap between the permanent magnets. Note that the positional relationship between the material having a high magnetic permeability and the material having a low magnetic permeability may be opposite to that described above.

  In order to reduce the interval at which the plurality of magnetic field concentrating members are arranged and to make the local concentrated magnetic field denser, carbon nanotubes having a magnetic material may be arranged on the magnetic pole surface. For example, it is conceivable that the carbon nanotubes are cut into circles and erected on the magnetic pole surface, and a magnetic material such as a permanent magnet is disposed in the carbon nanotubes.

  FIG. 3 shows a state on the XY plane of a protective member according to another embodiment of the present invention. Here, the plurality of magnetic field concentration members 3 and the protection member 4 are handled as an integral member. For example, the plurality of magnetic field concentrating members 3 are embedded in the protection member 4. This is different from the configuration of FIG. By doing in this way, the assembly | attachment and removal of each member with respect to the magnetic pole 2 become easy.

  FIG. 4 shows a state on the ZX plane of FIGS. 2 and 3. 2 and 3, the protective member 4 covers the entire surface of the magnetic pole 2, so that when viewed on the protective member 4 from the direction opposite to the Y direction in FIG. 4, the magnetic pole 2 is hidden by the protective member 4. can not see. However, since the protection member 4 only needs to cover the plurality of magnetic field concentration members 3, it does not have to be configured to cover the entire surface of the magnetic pole 2 in this way. This is just an example.

  In FIG. 4, their outlines are drawn with broken lines so that the positional relationship between the grooves 5 and the plurality of magnetic field concentrating members 3 can be easily understood. When actually viewed from above the protection member 4, these members cannot be seen unless the protection member 4 is made of a transparent material.

  At first glance in FIGS. 2 and 3, it seems that the groove 5 and the plurality of magnetic field concentrating members 3 must be separated from the top surface of the magnetic pole 2 in the Y direction, but this is not the case. As can be understood from FIG. 4, the position of the groove 5 and the magnetic field concentrating member 3 are different in the Z direction. Therefore, the groove 5 and the plurality of magnetic field concentrating members 3 may be arranged at the same height in the Y direction from the surface of the magnetic pole 2.

  FIG. 5 shows a state on the XY plane of a protective member according to another embodiment of the present invention. Although the upper surface in the Y direction of the protection member 4 shown in FIGS. 1 to 4 has a planar shape parallel to the ZX plane, it may not be such a planar shape.

  When the ion beam 8 draws a rectilinear trajectory, ideally all components constituting the ion beam draw a rectilinear trajectory. However, in reality, the ion beam 8 diverges due to the space charge effect. Therefore, the ion beam includes a straight traveling component and a diverging component. In FIG. 5, the component of the ion beam that travels straight is defined as component A, and the component of the diverging ion beam is defined as component B.

  In this case, the protection member 4 may be sputtered by the component B of the ion beam 8. When the protection member 4 protecting the plurality of magnetic field concentration members 3 is sputtered, the plurality of magnetic field concentration members 3 may be exposed from the protection member 4.

  When the plurality of magnetic field concentration members 3 are exposed, the plurality of magnetic field concentration members 3 are sputtered by the ion beam 8. As a result, there is a possibility of causing the problem of metal contamination when the member is deformed or performance is deteriorated due to the deformation, and when the plurality of magnetic field concentrating members are made of metal. When such a problem occurs, it becomes difficult to operate the ion beam irradiation apparatus stably for a long time.

  In order to improve such a point, it is conceivable to provide a plurality of protrusions 9 as shown in FIG. 5 on the protective member. The protruding portion 9 indicates a portion protruding in the Y direction from the surface of the protective member 4 located on the ZX plane, and is continuously formed like a ridge along the X direction. The height of each protrusion 9 from the surface of the magnetic pole 2 is set so as to gradually decrease along the X direction, which is the designed traveling direction of the ion beam 8. For example, the height from the magnetic pole surface of the protrusion 9 on the upstream side in the X direction is L1, and the height from the magnetic pole surface of the protrusion 9 on the downstream side in the X direction is L2. In this case, it is sufficient to set L1 to be larger than L2 and to decrease based on an arbitrary linear function from L1 to L2 along the X direction. In addition, a plurality of magnetic field concentrating members 3 are disposed below the protrusions 9. In other words, the protrusion is located between the ion beam and the magnetic field concentrating member.

  In this way, the component B of the ion beam, which is a divergent component, collides with the protrusion 9 provided on the protection member 4. This makes it difficult for the upper surface in the Y direction of the protrusion 9 on which the plurality of magnetic field concentrating members 3 are arranged to be scraped. Therefore, even when the ion beam irradiation apparatus is operated for a long time, the possibility that the plurality of magnetic field concentrating members 3 are sputtered by the ion beam 8 can be reduced.

  In addition, when such a configuration is used, the component B, which is a divergent component of the ion beam 8, can be removed from the ion beam 8 at a certain rate. Referring to the component B of the ion beam indicated by the alternate long and short dash line in FIG. 5, it collides with the highest portion of the protrusion 9 and is reflected. The component B of the reflected ion beam collides with another part of the protective member 4 and is reflected again. Eventually, the component B of the ion beam 8 travels in a direction approximately opposite to the component A of the ion beam. As a result, the ion beam 8 having only the ion beam component A can be irradiated toward a target surface such as a wafer or a glass substrate, which is an object to be irradiated, so that the defect rate related to the manufacture of semiconductor elements is improved. .

  FIG. 6 shows another embodiment of the configuration of the protrusion 9 shown in FIG. In FIG. 5, the highest portion of the protruding portion 9 is provided so as to stand vertically from the surface of the protective member 4, but the height of the protruding portion 9 extends along the X direction, which is the design traveling direction of the ion beam 8. If the height is set so as to gradually decrease, the same effect as the configuration shown in FIG. 5 can be obtained even with the configuration shown in FIG.

  5 and 6, the height of the protrusion 9 from the magnetic pole surface is set to decrease according to an arbitrary linear function along the traveling direction of the ion beam. However, the present invention is not limited to this. For example, you may set using arbitrary quadratic functions.

  FIG. 7 is an enlarged view of a main part related to the protrusion 9 in FIG. As can be seen in FIG. 7, it is conceivable to provide carbon nanotubes 10 that are finely cut on the surface of the protrusions 9 located on the upstream side in the X direction. In this case, since it is difficult to attach the carbon nanotubes 10 to the protrusions 9 one by one, a plurality of carbon nanotubes 10 are provided on a plate-shaped member made of carbon or the like in advance, and the protrusions are formed as one unit. 9 is attached.

  When such a carbon nanotube 10 is provided, when the component B of the ion beam shown in FIG. 5 collides with the carbon nanotube 10, the carbon nanotube 10 is cut into the inside of the carbon nanotube 10 that is cut or between the plurality of carbon nanotubes 10. In addition, it can be expected to confine the component B of the ion beam. This reduces the possibility that the component B of the ion beam is reflected from the protrusion 9 of the protection member 4.

  Even if it is reflected, since the component B of the ion beam collides with the carbon nanotube 10, the speed of the beam component B after being reflected is considerably decelerated compared with the case without the carbon nanotube 10. become. Therefore, it is possible to reduce the possibility that the component B of the ion beam reflected by the protrusion 9 reaches a target such as a wafer or a glass substrate that is an irradiation object.

  In addition, although the structure which attaches the carbon nanotube 10 to the protrusion part 9 was demonstrated taking the case of FIG. 5 as an example, even if it is the structure of the protrusion part 9 of FIG. 6, the carbon nanotube 10 as shown in FIG. I can do it.

  In the case of the protrusion 9 in FIG. 6, the carbon nanotube 10 is attached at a location where the component B of the ion beam collides in FIG. 6, that is, an ion beam that is not parallel to the X direction, which is the traveling direction of the designed ion beam. It may be provided in a place where the divergent component of the struck. Of course, since the state of the ion beam 8 changes variously, the carbon nanotubes 10 may be provided on the entire surface of the protrusion 9.

  Although the shape of the magnetic pole 2 shown in FIG. 1 is approximately rectangular, it may have a complicated curved shape as shown by a one-dot chain line in FIG.

  In such a case, since the shape of the magnetic pole 2 is complicated, it is expected that it is difficult to assemble the single protective member 4 that covers the entire surface of the magnetic pole 2 by sliding. That is, in the case of the shape of the magnetic pole 2 as shown in FIG. 8, when the single protective member 4 is slid, the protective member 4 may be caught while being slid.

  In order to solve this problem, the shape of the single protective member 4 is a rectangular shape that covers the entire surface of the magnetic pole 2, and then the side surface of the magnetic pole 2 in the Z direction so that the shape of the protective member 2 can be maintained. It is conceivable that the holding member 6 protrudes outward from the magnetic pole 2. However, in this case, both the holding member 6 and the protection member 4 must be large members, which leads to an increase in the size of the apparatus.

  Therefore, it is conceivable to divide the large protective member 4 covering the entire surface of the magnetic pole 2 into a plurality of parts in order to cope with such a complicated magnetic pole shape. In FIG. 8, the protective member 4 divided into two parts is used.

  FIG. 9 is a schematic diagram showing a state on the XY plane of FIG. Grooves 5 are individually provided on the side surfaces in the Z direction of the two protection members 4. The holding member 6 is also provided individually so as to correspond to the two protective members 4. In this case, the protective member 4 positioned on the upstream side (left side) in the X direction is assembled to the magnetic pole 2 by sliding along the X direction. On the other hand, the protective member 4 positioned on the downstream side (right side) in the X direction is assembled to the magnetic pole 2 by sliding along the direction opposite to the X direction. In order to understand the configuration described here, FIG. 10 which is a perspective view of FIG. 9 may be referred to.

  FIG. 11 is a perspective view drawn for easy understanding of the configuration of the holding member 6. This figure shows the state when the protective member 4 is removed from the previous FIG. As can be seen from FIG. 11, the shape of the holding member 6 is approximately along the shape of the magnetic pole, and the relationship between the holding members provided so as to face each other across the magnetic pole 2 is The relationship is substantially parallel along the vertical direction.

  By using the protective member 4 divided into a plurality in this way, even when the magnetic pole shape becomes complicated, it is difficult to assemble to the magnetic pole generated by using one protective member, and the size of the apparatus is increased. Can be eliminated.

  FIG. 12 shows another embodiment of the holding structure for the protection member 4. In the embodiments described so far, the configuration in which the groove 5 is provided in the protective member 4 has been described, but here, the protective member 4 is entirely slid in the space between the holding member 6 and the magnetic pole 2 by sliding the protective member 4. Is configured to fit. Therefore, it is not necessary to form the groove 5 in the protective member 4, so that the labor for manufacturing the groove 5 can be omitted.

  FIG. 13 shows a cross section when the structure is sheared along the Y direction along line AA shown in FIG. Also from this figure, it can be understood that the protection member 4 is fitted into the space created by the magnetic pole 2 and the holding member 6 by sliding.

  In the example shown in FIGS. 12 and 13, a part of the holding member 6 is exposed on the upper surface of the protection member 4. For this reason, the exposed holding member 6 is sputtered by the ion beam 8, and particles scattered from the ion beam 8 may be mixed into an irradiated object such as a wafer or a glass substrate. Therefore, it is conceivable that the holding member 6 is made of the same material as that of the protective member 4 such as carbon and the object to be irradiated, so that the amount of sputtering is reduced and the influence of mixing is reduced. In addition to devising the material, the sputtering of the retaining member 6 can be reduced to some extent by devising the retaining structure.

  This specific holding structure is shown in FIG. A recess 11 is provided at the end of the protective member 4, and the end of the holding member 6 is positioned in the recess 11. With such a configuration, the holding member 6 is positioned at a position far from the upper surface of the protective member 4 by the amount of the depression, so that the holding member 6 is hardly sputtered by the ion beam 8.

  Further, the area of the end portion of the holding member 6 exposed on the upper surface side of the protective member 4 may be reduced. In the example of FIG. 14, the end portion of the holding member 6 exposed along the X direction is not continuous. Furthermore, the protective member 4 may be configured to be held by using three small holding members 6 so as to be located on the upstream side in the X direction in FIG. 14, or the protective member 4 located on the downstream side in the X direction. It is also possible to adopt a configuration in which three portions are extended in a trifurcated manner so as to extend from one holding member 6 to the recess 11 of the protective member 4 as in the holding member 6 that holds the lens. In the example of FIG. 14 as well, the protection member 4 is assembled to the magnetic pole 2 by sliding as shown in FIG.

  8 to 14, the plurality of magnetic field concentrating members 3 are not necessary when describing the assembly of the protective member 4 to the magnetic pole 2, and are not shown. As a precaution, when a plurality of magnetic field concentrating members 3 are present on the magnetic pole 2 separately from the protective member 4, the protective member 4 is attached to the magnetic pole 2 by sliding. 4 is assembled such that the bottom surface of 4 slides on each of the plurality of magnetic field concentrating members 3. When the plurality of magnetic field concentration members 3 are integrally formed with the protection member 4, the protection member 4 is assembled such that the bottom surface of the protection member 4 slides on the magnetic pole 2.

  The embodiments of the magnet and the magnetic pole, magnetic field concentrating member, protective member and the like provided therein have been described above, but various improvements and modifications may be made without departing from the scope of the present invention. Of course. The magnet 1 according to the present invention may be a permanent magnet or an electromagnet. Further, the ion beam irradiation apparatus according to the present invention is an apparatus such as an ion implantation apparatus or an ion beam alignment apparatus, as long as it irradiates a substrate such as a silicon wafer with a positively charged ion beam. It may be.

1. Magnet 2. 3. Magnetic pole 3. Magnetic field concentration member Protective member
5. Groove 6. Holding member
7). Stopper 8. Ion beam 9. Projection 10. Carbon nanotubes11. Dent

Claims (5)

A magnet used in an ion beam irradiation apparatus,
A pair of magnetic poles arranged opposite each other so as to sandwich the ion beam inside the magnet;
A plurality of magnetic field concentrating members provided on opposing surfaces of the pair of magnetic poles to generate an electron confinement action between the magnetic poles;
A protective member that covers at least the surfaces facing each other across the ion beam in the plurality of magnetic field concentrating members, and a holding member having one end fixed to the magnetic pole,
The protection member slides on the magnetic pole or on the magnetic field concentration member in a state where movement to the ion beam side in a direction perpendicular to the surface of the magnetic pole is restricted by the other end of the holding member. The magnet is individually assembled to each of the magnetic poles constituting the pair of magnetic poles. The magnet according to claim 1, wherein the protection member includes a plurality of members .   When the design traveling direction of the ion beam passing between the magnetic poles is the X direction, the direction in which the pair of magnetic poles face each other is the Y direction, and the direction perpendicular to the X direction and the Y direction is the Z direction 3. A groove is provided on two side surfaces of the protective member intersecting the Z direction, and the other end of the holding member is inserted into the groove. Magnet. Together with the recess in the ion beam and the surface facing the protective member is formed, according to claim 1 or 2 wherein the magnet the other end of the holding member is characterized by being disposed in recess the .   A protrusion is formed on the protective member, and when the surface of the magnetic pole facing the ion beam is used as a reference, the height of the protrusion is a design traveling direction of the ion beam passing between the magnetic poles. The projection is located between the ion beam and the magnetic field concentrating member. magnet.