Ion implantation device and object irradiated by ion beam

Abstract

The present invention relates to an ion implantation device and an ion beam irradiated object, and is used to cope with nuclear reactions that may occur due to the use of an ion beam having relatively high energy. The ion implantation device (100) of the present invention comprises: an ion source configured to generate an ion beam containing ions of a first non-radioactive nuclide; a beam line configured to support an ion beam irradiated object (70) formed of a solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide; and a control device (50) configured to calculate at least one of an estimated amount of radiation generated by a nuclear reaction between the first non-radioactive nuclide and the second non-radioactive nuclide and an estimated amount of radioactive nuclide generated.

Description

[0001] This application is a divisional application of the application with application number 201810529805.3, application date May 29, 2018, and invention name “Ion implantation device and ion implantation method”. Technical Field

[0002] This application claims priority based on Japanese Patent Application No. 2017-107477 filed on May 31, 2017. The entire contents of that application are incorporated herein by reference.

[0003] The invention relates to an ion implantation device and an ion implantation method. Background Art

[0004] Conventionally, there is known an ion converter including: a member disposed on a path of an ion beam and capable of transmitting the ion beam; and a polarity conversion material coated on a surface of the member and converting the polarity of the ion beam by collision with the ion beam.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2000-156172

[0006] In the semiconductor manufacturing process, the process of implanting ions into the semiconductor wafer is generally carried out for the purpose of changing the conductivity, changing the crystal structure of the semiconductor wafer, etc. The device used in this process is usually called an ion implantation device. The ion implantation energy is determined according to the desired implantation depth of the ions into the wafer surface. A low-energy ion beam is used for implantation into a shallow area, and a high-energy ion beam is used for implantation into a deep area.

[0007] Recently, in order to implant deeper areas, the demand for so-called ultra-high energy ion implantation, which uses an ion beam with higher energy than the previous high energy ion implantation, is increasing. Ions accelerated to ultra-high energy may collide with components existing in the beam line of the ion implantation device and cause nuclear reactions. Depending on the nuclear reaction that occurs, radiation such as neutron beams or gamma rays may be generated. Sometimes, radioactive substances may also be generated. Summary of the invention

[0008] One of the exemplary purposes of one embodiment of the present invention is to cope with nuclear reactions that may occur due to the use of an ion beam having relatively high energy.

[0009] According to one embodiment of the present invention, an ion implantation apparatus is provided, characterized in that it comprises: an ion source configured to generate an ion beam containing ions of a first non-radioactive nuclide; a beam line configured to support an ion beam irradiated body having a first irradiated region and a second irradiated region; and a control device configured to select the first irradiated region when the energy of the ion beam is in a first energy region, and to select the second irradiated region when the energy of the ion beam is in a second energy region higher than the first energy region, the beam line comprising a relative position adjustment mechanism configured to adjust the relative position between the ion beam irradiated body and the ion beam in such a manner that the ions of the first non-radioactive nuclide are incident on the selected irradiated region, the first irradiated region being formed of a first solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide, and the second irradiated region being formed of a second solid material containing the second non-radioactive nuclide at a lower concentration than the first solid material or not containing the second non-radioactive nuclide.

[0010] According to one embodiment of the present invention, there is an ion implantation device, characterized in that it comprises: a beam line configured to support an ion beam irradiated body, the ion beam irradiated body having a first irradiated area allocated for an ion beam accelerated to a first energy region and a second irradiated area allocated for an ion beam accelerated to a second energy region higher than the first energy region; and a control device configured to select the first irradiated area when the energy of the ion beam incident on the ion beam irradiated body is within the first energy region, and to select the second irradiated area when the energy of the ion beam incident on the ion beam irradiated body is within the second energy region, the beam line comprising a relative position adjustment mechanism, configured to adjust the relative position between the ion beam irradiated body and the ion beam in such a manner that the ion beam is incident on the selected irradiated area.

[0011] According to one embodiment of the present invention, there is an ion beam irradiated body, which is an ion beam irradiated body on the beam line of an ion implantation device, characterized in that it has a plurality of irradiated areas located at different positions, and the plurality of irradiated areas include a high-energy dedicated irradiated area that is allocated to be dedicated to a high-energy ion beam accelerated to an energy exceeding a specified energy threshold.

[0012] In addition, any combination of the above-mentioned constituent elements or any method, apparatus, system, computer program, data structure, recording medium, etc. in which constituent elements or forms of expression of the present invention are mutually replaced may also be practiced as additional modes of the present invention.

[0013] Effects of the Invention

[0014] According to the present invention, it is possible to cope with nuclear reactions that may occur due to the use of an ion beam having relatively high energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a plan view schematically showing an ion implantation apparatus according to one embodiment of the present invention.

[0016] Figure 2 It is a rough representation Figure 1 A diagram showing the arrangement of components of an ion implantation apparatus.

[0017] Figure 3 This is a diagram illustrating the nuclear reaction cross-sectional area for the BC reaction.

[0018] Figure 4 This is a diagram illustrating an energy decay curve of boron.

[0019] Figure 5 This is a block diagram showing a schematic configuration of a control device for an ion implantation apparatus according to an embodiment.

[0020] Figure 6 (a) to Figure 6 (c) is a schematic diagram illustrating an example of a switching structure of a plurality of irradiation regions provided in an object irradiated with an ion beam.

[0021] Figure 7 (a) to Figure 7 (d) is a schematic diagram illustrating an example of a switching structure of a plurality of irradiation regions provided in an object irradiated with an ion beam.

[0022] Figure 8 (a) and Figure 8 (b) is a schematic diagram showing an example of an irradiation region of an object irradiated with an ion beam.

[0023] Fig. 9 This is a flowchart illustrating a switching process of an irradiation region of an object to be irradiated with an ion beam according to an embodiment.

[0024] Fig.10 This is a flowchart illustrating a switching process of an irradiation region of an object to be irradiated with an ion beam according to an embodiment.

[0025] Fig.11 (a) to Fig.11 (c) is a schematic diagram showing another example of an object irradiated with an ion beam.

[0026] Fig.12 This is a flowchart illustrating another switching process of the irradiation area of ​​the object to be irradiated with an ion beam according to one embodiment.

[0027] In the figure: 10-ion source, 14-high energy multi-stage linear acceleration unit, 40-wafer, 44-wafer support part, 50-control device, 54-nuclear reaction rate calculation part, 56-radiation dose calculation part, 57-radioactive nuclide generation amount calculation part, 70-ion beam irradiated body, 72-driving mechanism, 74-irradiated area, 74a-first irradiated area, 74b-second irradiated area, 75-solid material, 75a-first solid material, 75b-second solid material, 76-parent material, 77-surface part, 82-aperture plate, 100-ion implantation device, IB-ion beam. DETAILED DESCRIPTION

[0028] Hereinafter, with reference to the accompanying drawings, the method for implementing the present invention will be described in detail. In the description and the accompanying drawings, the same or equivalent components, parts, and processes are marked with the same symbols, and repeated descriptions are appropriately omitted. The scales and shapes of the various parts shown in the drawings are appropriately set for the convenience of description, and are not interpreted in a limiting sense unless otherwise specified. The implementation modes are illustrative and do not limit the scope of the present invention in any way. All the features and combinations thereof described in the implementation modes are not necessarily the essence of the invention.

[0029] Figure 1 It is a plan view schematically showing an ion implantation apparatus 100 according to an embodiment of the present invention. Figure 2 It is a rough representation Figure 1 FIG. 1 is a diagram showing the configuration of the components of the ion implantation device 100 shown in FIG. The ion implantation device 100 is suitable for a so-called high-energy ion implantation device. The high-energy ion implantation device is an ion accelerator having a high-frequency linear acceleration method and a beam line for high-energy ion transmission. The high-energy ion implantation device accelerates the ions generated in the ion source 10 to high energy, transmits the ion beam IB obtained thereby to a processed object (e.g., a substrate or a wafer 40) along the beam line, and implants ions into the processed object.

[0030] like Figure 1 and / or Figure 2 As shown, the ion implantation device 100 comprises: an ion beam generating unit 12, which generates ions and performs mass separation; a high-energy multi-stage linear acceleration unit 14, which accelerates the ions supplied from the ion beam generating unit 12 according to acceleration parameters; a beam deflection unit 16, which bends the trajectory of the ion beam IB into a U shape; a beam transmission line unit 18, which transmits the ion beam IB to the wafer 40; and a substrate processing supply unit 20, which uniformly implants the transmitted ion beam IB into the semiconductor wafer.

[0031] like Figure 2As shown, the ion beam generating unit 12 has an ion source 10, an extraction electrode 11 and a mass spectrometer 22. In the ion beam generating unit 12, the beam is accelerated while being extracted from the ion source 10 through the extraction electrode 11, and the extracted and accelerated beam is subjected to mass spectrometry analysis by the mass spectrometer 22. The mass spectrometer 22 has a mass spectrometer magnet 22a and a mass spectrometer slit 22b. The mass spectrometer slit 22b is arranged in the entrance part of the high energy multi-stage linear acceleration unit 14 which is the next component of the mass spectrometer 22. In addition, the mass spectrometer slit 22b can be arranged close to the rear side of the mass spectrometer magnet 22a (that is, close to the front side of the high energy multi-stage linear acceleration unit 14).

[0032] At the frontmost part of the linear acceleration part housing of the high-energy multi-stage linear acceleration unit 14, there is arranged a first beam measuring instrument 80a for measuring the total beam current of the ion beam. The first beam measuring instrument 80a is configured to be able to enter and exit from the upper and lower directions relative to the beam line through a driving mechanism. The first beam measuring instrument 80a is, for example, a Faraday cup. This Faraday cup is also called an injector Faraday cup. The injector Faraday cup is a rectangular bucket-shaped shape that is long in the horizontal direction, and is configured with the opening facing the upstream side of the beam line. The first beam measuring instrument 80a is used to measure the total beam current of the ion beam IB when adjusting the ion source 10 and / or the mass spectrometry magnet 22a. In addition, the first beam measuring instrument 80a can also be used to completely block the ion beam IB that reaches the downstream of the beam line on the beam line as needed.

[0033] Mass spectrometry is performed by the mass spectrometer 22, and as a result, only the ion species required for injection are selected, and the ion beam IB of the selected ion species is guided to the next high-energy multi-stage linear acceleration unit 14. The high-energy multi-stage linear acceleration unit 14 includes a first linear accelerator 15a used in conventional high-energy ion injection. The first linear accelerator 15a includes one or more (for example, multiple) high-frequency resonators 14a. The high-energy multi-stage linear acceleration unit 14 may include a second linear accelerator 15b in addition to the first linear accelerator 15a. The second linear accelerator 15b is used together with the first linear accelerator 15a for ultra-high energy ion injection and other ion injections. The second linear accelerator 15b includes one or more (for example, multiple) high-frequency resonators 14a. The direction of the ion beam IB accelerated by the high-energy multi-stage linear acceleration unit 14 changes by the beam deflection unit 16.

[0034] The first linear accelerator 15a includes a plurality of high-frequency resonators 14a and a plurality of convergent-divergent lenses 64. The high-frequency resonator 14a includes a cylindrical electrode. The convergent-divergent lens 64 is, for example, an electric field lens (for example, an electrostatic quadrupole electrode (Q lens)). The convergent-divergent lens 64 may be a magnetic field lens (for example, a quadrupole electromagnet). The cylindrical electrode of the high-frequency resonator 14a and the convergent-divergent lens 64 (for example, a Q lens) are alternately arranged in a row, and the ion beam IB passes through the center of them. The second linear accelerator 15b is also the same as the first linear accelerator 15a, and includes a plurality of high-frequency resonators 14a and a plurality of convergent-divergent lenses 64.

[0035] The convergence-divergence lens 64 is provided to control the convergence and divergence of the ion beam IB during or after acceleration and to effectively transmit the ion beam IB. The convergence-divergence lens 64 is arranged in the required number inside or before and after the high-frequency linear accelerator. The transverse convergence lens 64a and the longitudinal convergence lens 64b are arranged alternately. That is, the transverse convergence lens 64a is arranged in front of (or behind) the cylindrical electrode of the high-frequency resonator 14a, and the longitudinal convergence lens 64b is arranged behind (or in front of) the cylindrical electrode of the high-frequency resonator 14a. In addition, an additional longitudinal convergence lens 64b is arranged behind the transverse convergence lens 64a at the terminal of the second linear accelerator 15b. The convergence and divergence of the ion beam IB passing through the high-energy multi-stage linear acceleration unit 14 are adjusted, thereby incident on the ion beam IB with the two-dimensional beam distribution most suitable for the beam deflection unit 16 of the rear section.

[0036] In a high-frequency linear accelerator, as the acceleration parameters of the high frequency (RF), the amplitude V [kV] and the frequency f [Hz] of the voltage applied to the cylindrical electrode of each high-frequency resonator 14a are considered. When performing multi-stage high-frequency acceleration, the phase φ [deg] between the high-frequency resonators 14a is also added to the acceleration parameters. These amplitude V, frequency f and phase φ are parameters of the high frequency (RF). A fixed value can be used for the frequency f. In addition, the operating parameters (also called convergence-divergence parameters) of the convergence-divergence lens 64 are also considered. The convergence-divergence parameter is, for example, the Q lens voltage.

[0037] The high energy ion beam IB leaving the high energy multi-stage linear acceleration unit 14 has a certain range of energy distribution. Therefore, in order to irradiate the wafer 40 with the desired implantation accuracy after scanning and parallelizing the high energy ion beam IB, it is preferred to perform high-precision energy analysis, center trajectory correction, and beam convergence and divergence adjustment in advance.

[0038] The beam deflection unit 16 performs energy analysis, center trajectory correction, and energy dispersion control of the high energy ion beam. The beam deflection unit 16 has at least two high-precision deflection electromagnets, at least one energy width limiting slit and energy analysis slit, and at least one lateral convergence device. The multiple deflection electromagnets are configured to perform energy analysis of the high energy ion beam, precise correction of the ion implantation angle, and suppression of energy dispersion.

[0039] The beam deflection unit 16 includes an energy analysis magnet 24, an energy width limiting slit 27, a transverse convergence quadrupole lens 26, an energy analysis slit 28, and a steering magnet 30 in order from the upstream. The energy analysis magnet 24 is arranged downstream of the high energy multi-stage linear acceleration unit 14. The transverse convergence quadrupole lens 26 suppresses energy dispersion. The steering magnet 30 provides steering (orbit correction). The ion beam IB is redirected by the beam deflection unit 16 and directed toward the wafer 40.

[0040] A second beam measuring device 80b for measuring the beam current is provided downstream of the steering magnet 30. The second beam measuring device 80b is arranged at the frontmost part in the scanner housing, that is, close to the front part of the beam shaper 32. The second beam measuring device 80b is configured to be able to enter and exit from the upper and lower directions relative to the beam line through a driving mechanism. The second beam measuring device 80b is, for example, a Faraday cup. This Faraday cup is also called a resolver Faraday cup. The resolver Faraday cup is a rectangular bucket-shaped shape that is long in the horizontal direction, and is configured with the opening facing the upstream side of the beam line. The second beam measuring device 80b is used to measure the total beam current of the ion beam IB when adjusting the high-energy multi-stage linear acceleration unit 14 and / or the beam deflection unit 16. In addition, the second beam measuring device 80b is used to completely block the ion beam IB that reaches the downstream of the beam line on the beam line as needed.

[0041] The energy analyzing magnet 24 is one of the multiple deflection electromagnets of the beam deflecting unit 16 on the most upstream side. The energy analyzing magnet 24 is sometimes referred to as an energy filtering magnet (EFM). The turning magnet 30 is one of the multiple deflection electromagnets of the beam deflecting unit 16 on the most downstream side.

[0042] The ions passing through the deflection electromagnet of the beam deflection unit 16 are acted upon by centrifugal force and Lorentz force, and these forces are balanced to describe an arc-shaped trajectory. If the balance is expressed by a formula, it becomes mv=qBr. m is the mass of the ion, v is the velocity, q is the ion charge, B is the magnetic flux density of the deflection electromagnet, and r is the radius of curvature of the trajectory. Only ions whose radius of curvature r of the trajectory is consistent with the radius of curvature of the magnetic pole center of the deflection electromagnet can pass through the deflection electromagnet. In other words, when the valence of the ions is the same, only ions with a specific momentum mv can pass through the deflection electromagnet to which a certain magnetic field B is applied. In fact, the energy analysis magnet 24 is a device for analyzing the momentum of ions. Similarly, the steering magnet 30 and the mass spectrometry analysis magnet 22a are also momentum filters.

[0043] The beam deflection unit 16 can deflect the ion beam IB by 180° by using a plurality of magnets. Thus, a high-energy ion implantation device with a U-shaped beam line can be realized by a simple structure. The energy analysis magnet 24 and the steering magnet 30 are respectively configured to have a deflection angle of 90 degrees, and as a result, the total deflection angle is configured to be 180 degrees. In addition, the deflection amount performed by one magnet is not limited to 90°, and can also be the following combination.

[0044] (1) 1 magnet with a deflection of 90° + 2 magnets with a deflection of 45°

[0045] (2) Three magnets with a deflection of 60°

[0046] (3) 4 magnets with a deflection of 45°

[0047] (4) 6 magnets with a deflection of 30°

[0048] (5) 1 magnet with a deflection of 60° + 1 magnet with a deflection of 120°

[0049] (6) 1 magnet with a deflection of 30° + 1 magnet with a deflection of 150°

[0050] Since high magnetic field accuracy is required in the energy analysis magnet 24, a high-precision magnetic field measuring device 86 for precise magnetic field measurement is installed. The magnetic field measuring device 86 is a measuring device that appropriately combines an NMR (nuclear magnetic resonance) probe, also called an MRP (magnetic resonance probe), and a Hall probe. The MRP is used for calibration of the Hall probe, and the Hall probe is used for feedback control of magnetic field constancy. In addition, the energy analysis magnet 24 is manufactured with strict accuracy in such a way that the non-uniformity of the magnetic field is less than 0.01%. The magnetic field measuring device 86 is also provided in the steering magnet 30. In addition, the magnetic field measuring device 86 of the steering magnet 30 may only be installed with a Hall probe. In addition, the energy analysis magnet 24 and the steering magnet 30 are respectively connected with a current setting accuracy and current stability of 1×10-4 Power supplies and their control equipment within .

[0051] The beam transmission line unit 18 transmits the ion beam IB leaving the beam deflection unit 16, and has a beam shaper 32 composed of a convergent-divergent lens group, a beam scanner 34, a beam parallelizer 36, and an electrostatic final energy filter 38. The final energy filter 38 includes a final energy separation slit. The length of the beam transmission line unit 18 is designed in combination with the total length of the ion beam generation unit 12 and the high-energy multi-stage linear acceleration unit 14. The beam transmission line unit 18 is connected to the high-energy multi-stage linear acceleration unit 14 through the beam deflection unit 16, forming a U-shaped layout as a whole.

[0052] A substrate processing supply unit 20 is provided at the terminal on the downstream side of the beam transmission line unit 18. The substrate processing supply unit 20 has a vacuum processing chamber 21 for irradiating the ion beam IB to the wafer 40 during the implantation process. The vacuum processing chamber 21 contains: a beam monitor for measuring the beam current, position, implantation angle, convergence and divergence angle, ion distribution in the up, down, left and right directions, etc. of the ion beam IB; an antistatic device for preventing the wafer 40 from being charged by the ion beam IB; a wafer conveying mechanism for moving the wafer 40 in and out and setting it at a suitable position and angle; an ESC (Electrostatic Chuck) for holding the wafer 40 during ion implantation; and a wafer scanning mechanism for moving the wafer 40 in a direction perpendicular to the beam scanning direction at a speed corresponding to the change in the beam current during the implantation.

[0053] In the substrate processing supply unit 20, the third beam measuring device 80c is arranged behind the ion implantation position. The third beam measuring device 80c is, for example, a fixed horizontally long Faraday cup for measuring the total beam current of the ion beam IB. The horizontally long Faraday cup is also called an adjustment Faraday cup. The third beam measuring device 80c has a beam current measurement function capable of measuring the entire scanning range of the ion beam IB in the wafer area. The third beam measuring device 80c is configured to measure the final set beam at the most downstream of the beam line.

[0054] like Figure 1 As shown, in the substrate processing supply unit 20, a wafer conveying device 90 is provided adjacent to the vacuum processing chamber 21. The wafer conveying device 90 includes an intermediate conveying chamber, a load lock chamber, and an atmospheric conveying unit. The wafer conveying device 90 is configured to convey the processed objects such as wafers stored on the loading and unloading platform 92 to the vacuum processing chamber 21. The wafer is moved from the loading and unloading platform 92 to the vacuum processing chamber 21 via the atmospheric conveying unit, the load lock chamber, and the intermediate conveying chamber. On the other hand, the wafer that has been subjected to ion implantation is moved out to the loading and unloading platform 92 via the intermediate conveying chamber, the load lock chamber, and the atmospheric conveying unit.

[0055] In this way, the beamline of the ion implantation device 100 is configured as a horizontal U-shaped return beamline having two opposing long straight portions. The upstream long straight portion is composed of a plurality of units that accelerate the ion beam IB generated in the ion source 10. The downstream long straight portion is composed of a plurality of units that adjust the ion beam IB that is redirected relative to the upstream long straight portion to be implanted into the wafer 40. The two long straight portions are configured to be approximately the same length. Between the two long straight portions, a working space R1 of sufficient area is provided for maintenance operations.

[0056] The high energy ion implantation apparatus in which the units are arranged in a U shape can reduce the installation area and ensure good operability. In addition, in the high energy ion implantation apparatus, each unit or apparatus is configured as a module structure, so that it can be assembled and removed in conjunction with the beamline reference position.

[0057] Furthermore, since the high-energy multi-stage linear acceleration unit 14 and the beam transmission line unit 18 are arranged in a folded manner, the total length of the high-energy ion implantation device can be suppressed. In the previous device, these were arranged in a roughly straight line. Furthermore, the radius of curvature of the multiple deflection electromagnets constituting the beam deflection unit 16 is optimized to minimize the width of the device. Through these, the installation area of ​​the device is minimized, and in the working space R1 sandwiched between the high-energy multi-stage linear acceleration unit 14 and the beam transmission line unit 18, operations for each device of the high-energy multi-stage linear acceleration unit 14 and the beam transmission line unit 18 can be performed. Furthermore, since the ion source 10, which has a relatively short maintenance interval, is arranged adjacent to the substrate processing supply unit 20, which requires the supply / removal of the substrate, the operator only needs to move a small amount.

[0058] However, the ion implantation apparatus 100 may also be configured to be capable of ultra-high energy ion implantation. Here, ultra-high energy refers to, for example, an energy region of at least 4 MeV or at least 5 MeV. Ultra-high energy ion implantation allows desired impurity ions to be implanted into the wafer surface at a higher energy than typical high energy ion implantations, thereby enabling the desired impurities to be implanted into deeper regions (for example, a depth of more than 5 μm) on the wafer surface. Ultra-high energy ion implantation is used, for example, to form P-type regions and / or N-type regions in the manufacture of the latest semiconductor devices such as image sensors.

[0059] The ion source 10 is configured to generate an ion beam IB containing ions of a first non-radioactive nuclide. The high-energy multi-stage linear acceleration unit 14 is capable of accelerating the ion beam IB generated by the ion source 10 to an ultra-high energy of at least 5 MeV. The ion implantation device 100 may be provided with other linear acceleration mechanisms capable of accelerating the ion beam IB to ultra-high energy. However, the accelerator of the ion implantation device 100 is not limited to the linear acceleration mechanism. The ion implantation device 100 may be provided with any other accelerator capable of accelerating the ion beam IB to ultra-high energy, such as a tandem acceleration mechanism. The present invention is not limited to a specific ion acceleration method.

[0060] In addition, the ion implantation apparatus 100 is provided with a beam line configured to support an ion beam irradiated object. The ion beam irradiated object is formed of a solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide. The beam line is connected to the downstream of the high-energy multi-stage linear acceleration unit 14 or other accelerators, and can transmit the ion beam IB accelerated to ultra-high energy by the accelerator. The ion beam irradiated object is arranged on the beam line at a position where it can be irradiated with the ultra-high energy ion beam IB.

[0061] The beamline includes a plurality of beamline components. The beamline includes, as beamline components, an energy analysis magnet 24, a transverse convergence quadrupole lens 26, an energy width limiting slit 27, an energy analysis slit 28, a steering magnet 30, a beam shaper 32, a beam scanner 34, a beam parallelizer 36, a final energy filter 38, and a vacuum processing chamber 21. In addition, the beamline includes, as beamline components, beam current measuring instruments such as a second beam measuring instrument 80b and a third beam measuring instrument 80c.

[0062] The ion beam irradiated object may be at least a part of these beamline components. For example, the ion beam irradiated object may be configured as at least a part of a beam deflection device, an aperture plate, a beam shutter, a beam damper, a wafer support, or a wafer. The ion beam irradiated object may also be configured as at least a part of a beam current measuring device provided in the beamline.

[0063] The irradiated region of the ion beam IB in the irradiated body of the ion beam may be the inner wall of the region in which the beam deflection magnetic field for deflecting the beam is applied in the energy analysis magnet 24 or the steering magnet 30. The irradiated region may be an aperture plate for cutting out the desired component of the beam, for example, it may be a region including apertures in the energy width limiting slit 27 or the energy analysis slit 28. The irradiated region may be a beam shutter or a beam damper for shielding the beam. As described above, the beam current measuring device may be used as a beam shutter or a beam damper. The irradiated region may be a beam deflection electrode for generating a beam deflection electric field for deflecting the beam, for example, it may be a beam deflection electrode of the beam shaper 32, the beam scanner 34, the beam parallelizer 36 or the final energy filter 38.

[0064] The irradiated area may be the beam detection surface of a Faraday cup for ion current detection used to adjust the beam, for example, the beam detection surface of the second beam measuring device 80b, the third beam measuring device 80c or other beam current measuring devices. The irradiated area may be a wafer support 44 such as a plate provided on the surface of the wafer driving mechanism 42 and arranged around the wafer 40. The irradiated area may also be the wafer 40 or a dummy wafer.

[0065] The inventors have found that in ultra-high energy ion implantation, a nuclear reaction may occur between ions of a first non-radioactive nuclide incident on an object to be irradiated by an ion beam and a second non-radioactive nuclide contained in the object to be irradiated by an ion beam. As a result of the nuclear reaction, radiation such as neutron beams or gamma rays may be generated. Radioactive nuclide may also be generated. Even if the ion species used and the material of the object to be irradiated by an ion beam are non-radioactive nuclide, radiation problems may still occur. In typical ion implantations in the past, high energies to the extent that nuclear reactions become a problem in actual use were not used. Therefore, in previous ion implantation devices, the necessity of dealing with such nuclear reactions was not recognized.

[0066] For example, the first non-radioactive nuclide is boron 11 B. The second non-radioactive nuclide is carbon 12 When the ion beam IB is incident on the ion beam irradiated object at C, the following nuclear reaction may occur. Hereinafter, this nuclear reaction may be referred to as BC reaction.

[0067] 11 B+ 12 C→ 22 Na+n+kγ

[0068] Here, n represents a neutron beam, γ represents a gamma ray, and k is an integer. The higher the injection energy and the greater the ion beam current, the higher the nuclear reaction rate (i.e., the number of nuclear reactions per unit time) of the radiation produced as a result of the nuclear reaction, and it is possible that the rate will become more significant. Sodium, a product of the BC reaction,22 Na is a radioactive nuclide. 22 Na gradually disintegrates into neon with a half-life of 2.6 years 22 When the ion beam IB contains other ion species such as deuterium, carbon, and nitrogen with relatively small atomic numbers, or when the ion beam irradiated object is formed of a solid material containing an element with relatively small atomic numbers, it is also possible that radiation is generated due to nuclear reactions caused by the irradiation of the ion beam IB to the ion beam irradiated object.

[0069] Figure 3 This is a diagram illustrating the nuclear reaction cross-sectional area for the BC reaction. Figure 3 The vertical axis represents 11 B and 12 The cross-sectional area of ​​the nuclear reaction between C, the horizontal axis represents 11 The incident energy of B. Regarding the probability of a nuclear reaction, the larger the value of the nuclear reaction cross section, the easier it is for a nuclear reaction to occur. Figure 3 The results shown in the figure are theoretical calculation results. Figure 3 As shown, 11 When the incident energy of B is ultra-high energy of 5 MeV or more, the nuclear reaction cross-sectional area becomes relatively large, so it can be said that the BC reaction is likely to become a problem in practical use. 11 When the incident energy of B is ultra-high energy of 4MeV to 5MeV, the nuclear reaction cross-sectional area also becomes a relatively large value, so the BC reaction may become a problem in practical use. For example, if the beam current is large, the BC reaction may also occur significantly when the incident energy is 5MeV or less.

[0070] Figure 4 Boron is an example 11 The energy decay curve of B is shown in the figure. The material of the irradiated area is graphite, and an ultra-high energy of 7.5 MeV is incident on its surface. 11 Energy attenuation curve for B ions. The beam detection surface of the beam current measuring device such as the second beam measuring device 80b and the third beam measuring device 80c used in the ion implantation apparatus 100 is usually formed of graphite. In addition, the irradiated area of ​​other ion beam irradiated objects such as aperture plates, beam shutters, and beam dampers are also often formed of graphite. Figure 4 The vertical axis represents energy, and the horizontal axis represents the distance (depth) from the surface.

[0071] As shown in the figure, 11 The energy of B ions decreases with increasing depth. 11 The energy of the B ions decreases approximately linearly with increasing depth from the graphite surface. 11 As the incident energy of B ions increases, the energy decay curve moves upward. 11As the incident energy of the B ions decreases, the energy decay curve shifts downward, but the tendency that the energy decreases approximately linearly with increasing depth from the surface remains the same.

[0072] As in this example, when the incident energy is 7.5 MeV 11 B ions have an energy of 5 MeV or more up to a depth of 2.5 μm. Figure 3 hour, 11 When the energy of B ions is 5 MeV or more, the cross-sectional area of ​​nuclear reaction is relatively large. Therefore, the carbon atoms present in the region up to a depth of 2.5 μm 12 C is easy to be incident 11 B ions react with BC. A large amount of carbon is obviously present on the graphite surface. It is possible that a neutron beam is emitted with a significant amount from the region up to a depth of 2.5 μm in the graphite. On the other hand, in the region deeper than 4 μm, 11 The energy of B ions is attenuated to 3.5 MeV or less. Therefore, even if carbon exists in a region deeper than 4 μm, as long as the incident energy is 7.5 MeV or less, 11 B ions, the possibility of BC reaction is sufficiently small that it can be ignored in practical use.

[0073] In the operation of ion implantation equipment, it is desirable to fully suppress the generation of radiation and radioactive nuclides for safety. Furthermore, assuming that there is a certain degree of radiation generation and radioactive nuclides generation, it is desirable to manage the radiation dose and the generation of radioactive nuclides for safety. For example, when the implantation energy is high and the ion beam current is also large, it is expected that radiation will be generated at a relatively high dose or a relatively large amount of radioactive nuclides will be generated according to the ion beam irradiation conditions. In this case, it is necessary to monitor the radiation dose and manage the generation of radioactive nuclides according to the ion beam irradiation conditions.

[0074] From this point of view, the present inventors have studied several countermeasures for nuclear reactions that may occur due to ultra-high energy ion implantation on the beam line of the ion implantation apparatus 100. Such countermeasures will be described below using the BC reaction as an example.

[0075] The first countermeasure includes estimating the amount of radiation generated and / or the amount of radionuclide generated. The estimated radiation amount and the amount of radionuclide generated can be used for radiation dose management. The ion implantation device 100 can be configured to calculate at least one of the estimated radiation amount and the estimated amount of radionuclide generated due to the BC reaction between the carbon present in the irradiated area and the boron irradiated thereto. Appropriate warnings can also be displayed or output based on the estimated radiation amount and / or the estimated amount of radionuclide generated. Since the warning can prompt the operator to take necessary actions, the safety in the operation of the ion implantation device 100 can be improved.

[0076] Furthermore, an interlock for the radiation dose (e.g., neutron beam dose) may be set. It is foreseeable that when the radiation dose exceeds the set value, the ion implantation device 100 may prohibit the irradiation of the ion beam IB or stop the irradiation during the irradiation period. Similarly, an interlock for the accumulation of radioactive nuclides in the irradiated area may be set. In this way, the excessive generation of radiation is suppressed, which can improve the safety of the operation of the ion implantation device 100.

[0077] The second countermeasure is to change the material of the ion beam irradiated body. At least the irradiated area in the ion beam irradiated body is formed by a solid material containing an element with an atomic number (or atomic weight) larger than the material typically used in the past. In this way, the irradiated area is formed by a material containing an element with a larger atomic number, so it is not easy to cause a nuclear reaction in the irradiated area. In addition, even if it is a material containing an element with a smaller atomic number, it can be used as long as the probability of a nuclear reaction is reduced.

[0078] For example, for the irradiated area that was previously formed of graphite, the material is changed from graphite to a solid mixture or solid compound of at least one element with an atomic number greater than carbon and carbon, or a solid material containing at least one element with an atomic number greater than carbon but not containing carbon. In other words, the irradiated area can be formed of a material with a lower carbon concentration than graphite or a carbon-free material. In this way, an irradiated area with a reduced atomic number density or concentration of carbon can be formed. Therefore, even if the boron ion beam is incident on the irradiated area, the BC reaction is not likely to occur.

[0079] The third countermeasure includes switching of the irradiated area. A plurality of irradiated areas may be provided in a switchable manner on a certain ion beam irradiated body. The ion implantation apparatus 100 may be configured to select an irradiated area with a relatively small estimated amount of generated radiation from the plurality of switchable irradiated areas. The ion implantation apparatus 100 may also be configured to select an irradiated area with a relatively small estimated amount of generated radioactive nuclides from the plurality of switchable irradiated areas. If the ion beam IB is incident on the irradiated area selected in this way, excessive generation of radiation and / or excessive accumulation of radioactive nuclides are suppressed.

[0080] As a fourth countermeasure, the ion beam irradiated body has a plurality of irradiated regions located at different positions, and the plurality of irradiated regions may include a high-energy irradiated region dedicated to a high-energy ion beam accelerated to an energy exceeding a specified energy threshold. In addition, the plurality of irradiated regions may also include a low-energy irradiated region dedicated to a low-energy ion beam accelerated to an energy below a specified energy threshold. The ion implantation apparatus 100 may be configured to select an appropriate irradiated region from the plurality of irradiated regions according to the energy of the ion beam IB.

[0081] It can be as follows, that is, the dedicated low-energy irradiated region is formed of a first solid material, and the dedicated high-energy irradiated region is formed of a second solid material different from the first solid material. The first solid material contains a second non-radioactive nuclide, and the second solid material contains the second non-radioactive nuclide at a lower concentration than the first solid material or does not contain the second non-radioactive nuclide. Preferably, the second solid material contains an element with an atomic number greater than that of the second non-radioactive nuclide. In this way, the dedicated high-energy irradiated region is formed of a material containing an element with a larger atomic number, so that nuclear reactions in the dedicated high-energy irradiated region are not likely to occur. Regarding the dedicated low-energy irradiated region, nuclear reactions are not a problem in the first place, so it can be formed of any material.

[0082] As reference Figure 4 As explained above, the high-energy ion beam IB has high energy in the shallower region of the irradiated area, but loses energy as it moves toward the deeper region. As a result, the energy of the incident ion beam IB becomes lower at the deeper position, such as from Figure 3 It can be seen that a nuclear reaction is unlikely to occur.

[0083] Therefore, at least with respect to the high-energy dedicated irradiated area, different materials may be used in the shallower area and the deeper area of ​​the irradiated area. The ion beam irradiated body may include a base material and an irradiated area supported by the base material. The irradiated area may be a coating layer covering the base material. Alternatively, the base material may be formed of a first solid material and the irradiated area may be formed of a second solid material. Even so, a nuclear reaction in the high-energy dedicated irradiated area is not likely to occur.

[0084] These countermeasures can be implemented individually or in combination.

[0085] Figure 5 1 is a block diagram showing a schematic structure of a control device 50 of an ion implantation apparatus 100 according to an embodiment. The case where the ion beam irradiated object 70 is the second beam measuring device 80b is described as an example. This embodiment can also be applied to the case where the ion beam irradiated object 70 is the third beam measuring device 80c or other beam current measuring devices or other ion beam irradiated objects.

[0086] Each block shown in the block diagram of this specification can be realized by a component or circuit or mechanical device headed by a CPU or memory of a computer as a hardware structure, and can be realized by a computer program etc. as a software structure, but the functional blocks realized by their cooperation are described here. Therefore, those skilled in the art should understand that these functional blocks can be realized in various forms by a combination of hardware and software.

[0087] The control device 50 is configured to calculate the boron ions (for example, 11B ions) and carbon atoms (for example, 12 C) is an estimated dose of neutron beams generated by the BC reaction. Furthermore, the control device 50 is configured to calculate the radioactive nuclide generated by the BC reaction, that is, sodium 22 Estimated generation amount of Na.

[0088] The control device 50 includes a beam condition reading unit 51 , a nuclear reaction rate calculation unit 54 , a radiation dose calculation unit 56 , a radionuclide production amount calculation unit 57 , a warning display unit 58 , a beam irradiation control unit 59 , an irradiated region selection unit 60 , and a storage unit 62 .

[0089] Furthermore, the control device 50 includes an input unit 66 and an output unit 68. The input unit 66 is configured to receive input from an operator or other devices. The input unit 66 includes, for example, an input mechanism such as a mouse or a keyboard for receiving input from an operator and / or a communication mechanism for communicating with other devices. The output unit 68 is configured to output data related to the control of the ion implantation device 100, and includes an output mechanism such as a display or a printer. The control device 50 can receive data input from the input unit 66 and / or output data to the output unit 68.

[0090] The beam current measurement signal indicating the actual measured beam current measured by the second beam measuring device 80b is input to the control device 50. The control device 50 is configured to control the relative position adjustment mechanism, specifically, for example, the drive mechanism 72, the relative position adjustment mechanism is configured to adjust the relative position between the ion beam irradiated body 70 and the ion beam IB in such a way that ions are incident on the selected irradiated area, and the drive mechanism is configured to move the ion beam irradiated body 70 relative to the ion beam IB.

[0091] The beam condition reading unit 51 reads the ion beam irradiation conditions. The ion beam irradiation conditions include, for example, the material of the irradiated area, the area of ​​the irradiated area, the energy of the ion beam IB, the irradiation amount per unit time, the irradiation time, and the implantation angle. The ion beam irradiation conditions are input by the operator from the input unit 66 or read from the storage unit 62.

[0092] The nuclear reaction rate calculation unit 54 calculates the estimated nuclear reaction rate of the BC nuclear reaction in the ion beam irradiated body 70. The nuclear reaction rate indicates the number of nuclear reactions that occur per unit time. The nuclear reaction rate calculation unit 54 can calculate the estimated nuclear reaction rate based on the energy of the ion beam IB, the irradiation amount per unit time, and the carbon atoms (e.g., 12The estimated nuclear reaction rate is calculated by the atomic number density of the BC reaction. The nuclear reaction rate calculation unit 54 can calculate the estimated nuclear reaction rate by a known calculation method for calculating the nuclear reaction rate of the BC reaction. The nuclear reaction rate calculation unit 54 stores the calculated estimated nuclear reaction rate in the storage unit 62.

[0093] The energy of the ion beam IB used in the calculation can be assigned as an energy attenuation curve determined by the incident energy to the surface of the irradiated area and the material of the irradiated area. Alternatively, in order to reduce the calculation load, the injection depth of the ion beam IB can be assumed to be fixed (for example, 10 μm) according to the injection range, and the energy of the ion beam IB can be assumed to be a constant value in the depth direction (for example, a value equal to the incident energy to the surface of the irradiated area). Therefore, since the energy of the deeper area is assumed to be higher than the actual value, the estimated radiation dose and the estimated generation amount of radioactive nuclides are calculated to be larger than the actual amount. Therefore, it is believed that the actual amount of radiation generated and the generation amount of radioactive nuclides are less than the inferred amount. It is equivalent to setting a larger safety factor for the inference, so it is safer.

[0094] The irradiation amount per unit time used in the calculation may be an estimated value calculated based on the ion beam irradiation conditions or may be an actual measured beam current measured by the second beam measuring device 80 b of the ion beam irradiated object 70 to improve the estimation accuracy.

[0095] The radiation dose calculation unit 56 calculates the estimated radiation dose of the neutron beam based on the estimated nuclear reaction rate calculated by the nuclear reaction rate calculation unit 54. The radiation dose calculation unit 56 can calculate the estimated radiation dose of the neutron beam by a known calculation method for calculating the amount of the neutron beam generated by the BC reaction. The radiation dose calculation unit 56 can calculate the estimated radiation dose at a desired position outside the beam line or outside the ion implantation device 100 based on the calculated estimated radiation dose of the neutron beam, the position information of the ion beam irradiated body 70 in the beam line, and the configuration information of the radiation shielding material possessed by the beam line. In this way, the estimated radiation dose at any time point can be managed. The radiation dose calculation unit 56 stores the calculated estimated radiation dose of the neutron beam in the storage unit 62. The calculated estimated radiation dose of the neutron beam can also be output to the output unit 68.

[0096] The radioactive nuclide generation amount calculation unit 57 calculates the sodium 22 The radionuclide generation amount calculation unit 57 can calculate the sodium generated by the BC reaction by a known calculation method. 22 The radionuclide generation amount calculation unit 57 calculates the estimated generation amount of Na. 22 The estimated production amount of Na is stored in the storage unit 62. 22The estimated generation amount of Na may also be output to the output unit 68 .

[0097] The radionuclide generation amount calculation unit 57 can calculate the cumulative estimated generation amount of radionuclide accumulated in the ion beam irradiated body 70 by integrating the estimated generation amount of radionuclide calculated according to each ion beam irradiation condition. According to a certain ion beam irradiation condition, each time the ion beam irradiates a certain irradiated area of ​​the ion beam irradiated body 70, radionuclide may be generated and accumulated. The total amount of radionuclide accumulated in the irradiated area as a result of repeated ion beam irradiation under various ion beam irradiation conditions is given by the accumulation of the generation amount of radionuclide according to each ion beam irradiation condition. However, the accumulation amount of radionuclide decreases over time due to the disintegration of radionuclide. Therefore, when the radionuclide generation amount calculation unit 57 integrates the estimated generation amount of radionuclide calculated according to each ion beam irradiation condition, it can reflect the reduction in radionuclide due to disintegration.

[0098] The warning display unit 58 can determine whether the estimated dose of the neutron beam calculated by the radiation dose calculation unit 56 exceeds the prescribed upper limit dose. In addition, the warning display unit 58 can determine whether the estimated generation amount of radioactive nuclides (for example, the cumulative estimated generation amount) calculated by the radioactive nuclides generation amount calculation unit 57 exceeds the prescribed upper limit value. The warning display unit 58 displays a warning when the estimated dose of the neutron beam exceeds the prescribed upper limit dose and / or when the estimated generation amount of radioactive nuclides exceeds the prescribed upper limit value. The warning can be output to the output unit 68. The warning can be a warning to urge the replacement of the ion beam irradiated body 70. The warning display unit 58 does not display a warning when the estimated dose of the neutron beam does not exceed the prescribed upper limit dose. The warning display unit 58 does not display a warning when the estimated generation amount of radioactive nuclides does not exceed the prescribed upper limit value. The prescribed upper limit dose and the prescribed upper limit value can be appropriately set, for example, based on experience or experimental insights.

[0099] The beam irradiation control unit 59 can determine whether the estimated dose of the neutron beam calculated by the radiation dose calculation unit 56 exceeds the prescribed upper limit dose. In addition, the beam irradiation control unit 59 can determine whether the estimated generation amount of radioactive nuclides calculated by the radioactive nuclides generation amount calculation unit 57 (for example, the cumulative estimated generation amount) exceeds the prescribed upper limit value. The beam irradiation control unit 59 can prohibit the ion beam IB from irradiating the ion beam irradiated body 70 when the estimated dose of the neutron beam exceeds the prescribed upper limit dose and / or when the estimated generation amount of radioactive nuclides exceeds the prescribed upper limit value. When the ion beam IB is not currently generated, the beam irradiation control unit 59 can not allow subsequent ion beam irradiation. During the ion beam irradiation, the beam irradiation control unit 59 can terminate the ion beam irradiation. When the estimated dose of the neutron beam does not exceed the prescribed upper limit dose, the beam irradiation control unit 59 can allow or continue the ion beam irradiation. When the estimated generation amount of radioactive nuclides does not exceed the prescribed upper limit value, the beam irradiation control unit 59 can allow or continue the ion beam irradiation. The upper limit dose and upper limit value for determining prohibition of irradiation may be the same as or different from the upper limit dose and upper limit value for warning.

[0100] Regarding the ion beam irradiated body 70 having only a single irradiated area, when the estimated radiation dose of the neutron beam exceeds the specified upper limit radiation dose and / or the estimated generation amount of radioactive nuclides exceeds the specified upper limit value, the ion beam irradiated body 70 can be replaced with a new one at an appropriate opportunity such as the next maintenance operation.

[0101] The ion beam irradiated body 70 may have a plurality of irradiated regions located at different positions. The irradiated region selection unit 60 may select any irradiated region from the plurality of irradiated regions of the ion beam irradiated body 70 in such a manner that the estimated radiation dose of the neutron beam calculated by the radiation dose calculation unit 56 is lower than a prescribed upper limit radiation dose. The irradiated region selection unit 60 may select any irradiated region from the plurality of irradiated regions of the ion beam irradiated body 70 in such a manner that the estimated generation amount of radioactive nuclides calculated by the radioactive nuclides generation amount calculation unit 57 is lower than a prescribed upper limit value. The irradiated region selection unit 60 may control the drive mechanism 72 to move the ion beam irradiated body 70 relative to the ion beam IB in such a manner that ions are incident on the selected irradiated region.

[0102] The irradiated region selection unit 60 may reselect a different irradiated region each time the ion beam irradiation conditions are changed. The irradiated region selection unit 60 may reselect a different irradiated region when the estimated dose of the neutron beam for the selected irradiated region exceeds a prescribed upper limit dose and / or when the estimated generation amount of radioactive nuclides exceeds a prescribed upper limit value.

[0103] The ion implantation apparatus 100 may include, as an example of a relative position adjustment mechanism, an ion beam deflection mechanism configured to deflect the ion beam IB so that the ion beam IB is irradiated onto a selected irradiation target region.

[0104] Figure 6 (a) to Figure 6 (c) is a schematic diagram illustrating an example of a switching structure of a plurality of irradiation regions 74 provided in the ion beam irradiated object 70. Figure 6 (a) shows the second beam measuring device 80b. Figure 6 (b) and Figure 6 The aperture plate 82 is shown in (c).

[0105] like Figure 6 As shown in (a), the second beam measuring device 80b has four irradiated areas 74 arranged in two rows and two columns on one side of the plate-like member. Each irradiated area 74 is a Faraday cup. The driving mechanism 72 can move the second beam measuring device 80b along the vertical and horizontal axes on the plane where the irradiated areas 74 are arranged, and can move the second beam measuring device 80b in a manner that the ion beam IB (not shown) is incident on any irradiated area 74. The ion beam IB is incident on the second beam measuring device 80b in a direction perpendicular to the paper surface.

[0106] In addition, the irradiated area 74 and the Faraday cup do not necessarily have to correspond one to one. A plurality of irradiated areas 74 may be provided in one Faraday cup. That is, a certain area in the beam detection surface of the Faraday cup may be used as one irradiated area 74, and other areas that do not overlap with this area may be used as other irradiated areas 74. Alternatively, a plurality of Faraday cups may be provided in one irradiated area 74.

[0107] like Figure 6 As shown in (b), the aperture plate 82 has two slits 83 extending in parallel, and each slit 83 is provided with an irradiated area 74. The irradiated area 74 and the slits 83 may correspond one to one or may not correspond one to one. Figure 6 As shown in (c), a plurality of irradiated regions 74 may be arranged so as not to overlap each other along one slit 83. For example, the upper portion of the slit 83 may be used as one irradiated region 74, and the lower portion of the slit 83 may be used as another irradiated region 74 so as not to overlap with the upper portion of the slit 83.

[0108] The configuration of the plurality of irradiated regions 74 and the moving direction of the ion beam irradiated body 70 can be various. Figure 7 (a) to Figure 7 (d).

[0109] Can be as Figure 7As shown in (a), the ion beam irradiated body 70 has a planar shape, and a plurality of irradiated regions 74 are arranged on the plane. The driving mechanism 72 moves the ion beam irradiated body 70 in a direction parallel to the plane, thereby switching the irradiated regions 74. The plurality of irradiated regions 74 may also be arranged in a row, and the driving mechanism 72 may move the ion beam irradiated body 70 along the arrangement direction of the irradiated regions 74. Figure 7 As shown in (b), a plurality of irradiated regions 74 are arranged on the front and back surfaces of the plane, and the driving mechanism 72 reverses the ion beam irradiated body 70 to switch the irradiated regions 74.

[0110] You can also Figure 7 As shown in (c), the ion beam irradiated body 70 has a prism shape (for example, a triangular prism shape or a quadrangular prism shape), and a plurality of irradiated regions 74 are arranged on the side of the prism. The driving mechanism 72 rotates the ion beam irradiated body 70 around the central axis of the prism or an axis parallel thereto, thereby switching the irradiated regions 74. One irradiated region 74 may be arranged on each side of the prism, or a plurality of irradiated regions 74 may be arranged on each side of the prism. When a plurality of irradiated regions 74 are arranged on one side, the driving mechanism 72 may move the ion beam irradiated body 70 parallel to the side, thereby switching the irradiated regions 74.

[0111] You can also Figure 7 As shown in (d), the ion beam irradiated body 70 has a cylindrical shape, and a plurality of irradiated regions 74 are arranged at different angular positions on the side of the cylinder. The driving mechanism 72 rotates the ion beam irradiated body 70 around the central axis of the cylinder or an axis parallel thereto, thereby switching the irradiated regions 74. One irradiated region 74 may be arranged at each different angular position of the cylinder, or a plurality of irradiated regions 74 may be arranged at the same angular position of the cylinder. The driving mechanism 72 may move the ion beam irradiated body 70 in the direction of the central axis, thereby switching the irradiated regions 74.

[0112] Figure 8 (a) and Figure 8 (b) is a schematic diagram showing an example of an irradiated area 74 of an ion beam irradiated object 70. Figure 8 As shown in (a), the irradiated area 74 is formed by a solid material 75. The solid material 75 contains carbon and at least one element with an atomic number greater than carbon. Alternatively, the solid material 75 is composed only of elements with an atomic number greater than carbon (in this case, the solid material 75 does not contain carbon). Elements with an atomic number greater than carbon are, for example, aluminum (Al), silicon (Si), molybdenum (Mo), tantalum (Ta), and tungsten (W). The solid material 75 can be a solid mixture or a solid compound of carbon and at least one element with an atomic number greater than carbon. For example, the solid material 75 can be a mixture of carbon (for example, graphite) and aluminum. The solid material 75 can also be SiC or Si x Cy (x, y represent composition ratios.) Thus, an irradiated region 74 can be formed in which the atomic density or concentration of carbon is lower than that of a typical graphite irradiated region. Therefore, even if the boron ion beam IB is incident on the irradiated region 74, a BC reaction is unlikely to occur.

[0113] like Figure 8 As shown in (b), the ion beam irradiated body 70 includes a base material 76 and a surface portion 77 supported by the base material 76. The surface portion 77 is formed on the base material 76. The surface portion 77 may be a coating layer covering the base material 76. The surface portion 77 may be formed on the surface of the base material 76 by an appropriate film forming method such as vapor deposition. The exposed surface of the surface portion 77 is used as the irradiated area 74.

[0114] The base material 76 is formed of graphite or other suitable solid materials. The base material 76 can be formed only of graphite. The surface portion 77 is formed of the above-mentioned solid material 75. That is, the surface portion 77 is formed of a solid material containing carbon and at least one element with an atomic number greater than carbon, or a solid material consisting only of elements with an atomic number greater than carbon. In this way, the ion beam IB incident on the irradiated area 74 enters the deep part of the base material 76 after the energy is attenuated in the surface portion 77. The surface portion 77 has a lower atomic number density or concentration of carbon than the typical graphite irradiated area in the past. Therefore, even if the boron ion beam IB is incident on the irradiated area 74, the BC reaction is not likely to occur.

[0115] Fig. 9 1 is a flowchart illustrating a switching process of the irradiated area 74 of the ion beam irradiated body 70 involved in one embodiment. The process is executed by the control device 50. When the process is started, first, the ion beam irradiation conditions are read into the beam condition reading unit 51 of the control device 50 (S10). The read ion beam irradiation conditions are, for example, the ion beam irradiation conditions used in the next irradiation. Alternatively, for example, for the calculation of the radiation dose, any other ion beam irradiation conditions can be read into the control device 50.

[0116] The irradiated region 74 is selected ( S12 ). The irradiated region selection unit 60 may directly select the irradiated region 74 selected in the previous process. Alternatively, the irradiated region selection unit 60 may reselect another irradiated region 74 .

[0117] The estimated radiation dose is calculated (S14). Figure 5 As described above, the control device 50 calculates the estimated dose of radiation generated from the selected irradiation area 74 based on the read ion beam irradiation conditions and the material of the selected irradiation area 74 .

[0118] The irradiated area selection unit 60 determines whether the calculated estimated radiation dose exceeds the prescribed upper limit dose (S16). When the calculated estimated radiation dose exceeds the prescribed upper limit dose (No in S16), it is determined whether there are other irradiated areas 74 that can be selected (S17). When there are other irradiated areas 74 that can be selected (Yes in S17), the irradiated area selection unit 60 selects the other irradiated areas 74 (S12). Here, the irradiated area selection unit 60 selects the irradiated area 74 for which the estimated radiation dose is not determined to exceed the prescribed upper limit dose. The irradiated area 74 for which the estimated radiation dose is determined to exceed the prescribed upper limit dose in the past processing is not selected. For the selected irradiated area 74, the estimated radiation dose is calculated (S14), and it is confirmed again whether the calculated estimated radiation dose exceeds the prescribed upper limit dose (S16).

[0119] When there is no other selectable irradiation region 74 (No in S17 ), the irradiation region selection unit 60 displays a warning ( S19 ) and prohibits irradiation of the ion beam to the ion beam irradiated object 70 ( S21 ).

[0120] When the calculated estimated dose of radiation does not exceed the prescribed upper limit dose (Yes in S16), the ion beam IB is irradiated on the selected irradiation area 74 (S18). The relative position between the ion beam irradiated body 70 and the ion beam IB is adjusted in such a way that the ions are incident on the selected irradiation area 74, and at this position, the ion beam irradiated body 70 is supported on the beam line. The ion beam IB is generated by the ion source 10 and accelerated by the high-energy multi-stage linear acceleration unit 14. The ion beam IB is transmitted through the beam line after the high-energy multi-stage linear acceleration unit 14 and irradiated on the ion beam irradiated body 70. In this way, the present process ends.

[0121] Fig.10 1 is a flowchart illustrating another switching process of the irradiation region 74 of the ion beam irradiated body 70 according to one embodiment. The process is executed by the control device 50. When the process starts, first, the ion beam irradiation conditions are read into the beam condition reading unit 51 of the control device 50 (S10). Next, the irradiation region 74 is selected (S12).

[0122] Calculate the estimated generation amount of radioactive nuclides (S20). Figure 5 As described above, the control device 50 calculates the estimated generation amount of radioactive nuclides in the selected irradiation area 74 based on the read ion beam irradiation conditions and the material of the selected irradiation area 74 .

[0123] The irradiated area selection unit 60 determines whether the calculated estimated generation amount of radioactive nuclides exceeds the prescribed upper limit value (S22). When the calculated estimated generation amount of radioactive nuclides exceeds the prescribed upper limit value (No in S22), it is determined whether there are other irradiated areas 74 that can be selected (S17). When there are other irradiated areas 74 that can be selected (Yes in S17), the irradiated area selection unit 60 selects the other irradiated areas 74 (S12). Here, the irradiated area selection unit 60 selects the irradiated area 74 that is not determined to have an estimated generation amount of radioactive nuclides exceeding the prescribed upper limit value. The irradiated area 74 that was determined to have an estimated generation amount of radioactive nuclides exceeding the prescribed upper limit value in the past processing is not selected. For the selected irradiated area 74, the estimated generation amount of radioactive nuclides is calculated (S20), and it is confirmed whether the calculated estimated generation amount of radioactive nuclides exceeds the prescribed upper limit value (S22).

[0124] When there is no other selectable irradiation region 74 (No in S17 ), the irradiation region selection unit 60 displays a warning ( S19 ) and prohibits irradiation of the ion beam to the ion beam irradiated object 70 ( S21 ).

[0125] When the calculated estimated generation amount of radioactive nuclides does not exceed the prescribed upper limit value (Yes in S22), the ion beam IB is irradiated on the selected irradiation area 74 (S24). The relative position between the ion beam irradiated body 70 and the ion beam IB is adjusted in such a way that the ions are incident on the selected irradiation area 74, and the ion beam irradiated body 70 is supported on the beam line at this position. The ion beam IB is generated by the ion source 10 and accelerated by the high-energy multi-stage linear acceleration unit 14. The ion beam IB is transmitted through the beam line after the high-energy multi-stage linear acceleration unit 14 and irradiated on the ion beam irradiated body 70.

[0126] After the ion beam IB is irradiated to the ion beam irradiated object 70, the estimated generation amount of the radionuclide in the selected irradiated area 74 is updated (S26). The radionuclide generation amount calculation unit 57 integrates the estimated generation amount of the radionuclide based on the irradiation of the ion beam IB this time with the existing estimated generation amount. The estimated generation amount of the radionuclide updated in this way is stored in the storage unit 62, and this process ends.

[0127] Fig.11 (a) to Fig.11 (c) is a schematic diagram illustrating another example of the ion beam irradiated object 70. Fig.11As shown in (a), the ion beam irradiated body 70 includes a first irradiated area 74a and a second irradiated area 74b arranged along a driving direction based on a driving mechanism 72. Therefore, the ion beam irradiated body 70 can select an irradiated area irradiated by the ion beam IB from the first irradiated area 74a and the second irradiated area 74b by the driving of the driving mechanism 72. The ion beam irradiated body 70 can be a second beam measuring device 80b or other beam current measuring devices. The first irradiated area 74a and the second irradiated area 74b can be Faraday cups, respectively. The ion beam irradiated body 70 can also be other ion beam irradiated bodies.

[0128] Ion beams IB accelerated to different energies are incident on the first irradiation region 74a and the second irradiation region 74b. The first irradiation region 74a is allocated for ion beams accelerated to the first energy range, and the second irradiation region 74b is allocated for ion beams accelerated to the second energy range.

[0129] The second energy region is an energy region higher than the first energy region. The second energy region is, for example, located in an ultra-high energy region of 4 MeV or more or 5 MeV or more. In other words, the value of the lower limit energy of the second energy region is selected from the ultra-high energy region of 4 MeV or more or 5 MeV or more. The first energy region is, for example, located in an energy region of less than 4 MeV or less than 5 MeV. The value of the upper limit energy of the first energy region is selected from an energy region of less than 4 MeV or less than 5 MeV. The first energy region and the second energy region can be appropriately set, for example, based on experience or experimental insights.

[0130] If necessary, the ion beam irradiated body 70 may be provided with a third irradiated region allocated for the ion beam accelerated to a third energy range higher than the second energy range.

[0131] in addition, Fig.11 In the example shown in (a), the ion beam irradiated body 70 has one first irradiated area 74a and one second irradiated area 74b, but the ion beam irradiated body 70 may also have multiple first irradiated areas 74a and multiple second irradiated areas 74b. Ion beams of different energies may be allocated to the multiple first irradiated areas 74a (or the second irradiated areas 74b), respectively. Alternatively, the multiple first irradiated areas 74a (or the second irradiated areas 74b) may also be allocated to the multiple first irradiated areas 74a (or the second irradiated areas 74b). Figure 6 (a) to Figure 6 The region shown in (c) is the same and switches regardless of energy.

[0132] Can be as Figure 7As shown in (b), the ion beam irradiated body 70 has a planar shape, the first irradiated region 74a is arranged on the surface of the ion beam irradiated body 70, and the second irradiated region 74b is arranged on the back of the ion beam irradiated body 70. The first irradiated region 74a and the second irradiated region 74b can be switched as follows, that is, by reversing the ion beam irradiated body 70 by the driving mechanism 72.

[0133] You can also Figure 7 As shown in (c), the ion beam irradiated body 70 has a prism shape, the first irradiated area 74a is arranged on one side of the prism, and the second irradiated area 74b is arranged on the other side of the prism. The first irradiated area 74a and the second irradiated area 74b can be switched by rotating the ion beam irradiated body 70 around the central axis of the prism or an axis parallel thereto by the driving mechanism 72. Figure 7 As shown in (d), the ion beam irradiated body 70 has a cylindrical shape, the first irradiated area 74a is arranged at a certain angle position on the side of the cylinder, and the second irradiated area 74b is arranged at another angle position on the side of the cylinder. The first irradiated area 74a and the second irradiated area 74b can be switched as follows, that is, by rotating the ion beam irradiated body 70 around the central axis of the cylinder or an axis parallel thereto by the driving mechanism 72.

[0134] You can also Fig.11 As shown in (b), a first ion beam irradiated body 70a having a first irradiated area 74a and a second ion beam irradiated body 70b having a second irradiated area 74b are provided. The first ion beam irradiated body 70a and the second ion beam irradiated body 70b can be switched by respectively setting the first ion beam irradiated body 70a and the second ion beam irradiated body 70b to be movable. The first ion beam irradiated body 70a can be driven by the first driving mechanism 72a, and the second ion beam irradiated body 70b can be driven by the second driving mechanism 72b.

[0135] You can also Fig.11 As shown in (c), one of the first ion beam irradiated body 70a and the second ion beam irradiated body 70b is fixed, and the other is movable by a driving mechanism 72. The first ion beam irradiated body 70a (or the second ion beam irradiated body 70b) is fixed, and the second ion beam irradiated body 70b (or the first ion beam irradiated body 70a) is able to advance and retreat relative to the path of the ion beam IB at a position adjacent to the first irradiated area 74a (or the second irradiated area 74b).

[0136] The multiple irradiated regions 74 of the ion beam irradiated body 70 can be allocated according to the ion types. For example, the ion beam irradiated body 70 can have an irradiated region for boron and an irradiated region for other ion types. The irradiated region for boron can be provided with the above-mentioned first irradiated region 74a and second irradiated region 74b. Alternatively, it can also be as follows, that is, the first irradiated region 74a is allocated to the low-energy ion beam of boron and the ion beam of other ion types, and the second irradiated region 74b is allocated to the high-energy ion beam of boron.

[0137] The first irradiated region 74a is formed of a first solid material 75a. The first solid material 75a may be graphite, and the first irradiated region 74a may be formed of only graphite. The first solid material 75a may also be other appropriate solid materials.

[0138] The second irradiated area 74b is formed by a second solid material 75b. The second solid material 75b contains carbon and at least one element with an atomic number greater than carbon. Alternatively, the second solid material 75b is composed only of elements with an atomic number greater than carbon (in this case, the second solid material 75b does not contain carbon). Elements with an atomic number greater than carbon are, for example, aluminum (Al), silicon (Si), molybdenum (Mo), tantalum (Ta), and tungsten (W). The second solid material 75b may also be a solid mixture or solid compound of carbon and at least one element with an atomic number greater than carbon. For example, the second solid material 75b may be a mixture of carbon (e.g., graphite) and aluminum. The second solid material 75b may also be SiC or Si x C y (x, y represent composition ratios.) Thus, a second irradiated region 74b can be formed in which the atomic number density or concentration of carbon is reduced compared to a typical graphite irradiated region. Therefore, even if the boron ion beam IB is incident on the second irradiated region 74b, a BC reaction is unlikely to occur.

[0139] The second irradiated area 74b can be Figure 8 The irradiated region 74 shown in (b) is similar and includes a base material and a surface layer portion supported by the base material. The base material may be formed of a first solid material 75a, and the surface layer portion may be formed of a second solid material 75b.

[0140] Fig.12 1 is a flowchart illustrating another switching process of the irradiation area 74 of the ion beam irradiated body 70 according to one embodiment. This process is executed by the control device 50. When the process starts, first, the ion beam irradiation conditions are read into the beam condition reading unit 51 of the control device 50 (S11).

[0141] Next, the ion beam irradiation conditions are determined. The irradiated area selection unit 60 determines whether the energy of the ion beam incident on the ion beam irradiated body 70 is located in the first energy region or the second energy region (S30). When the energy of the ion beam incident on the ion beam irradiated body 70 is located in the first energy region, the irradiated area selection unit 60 selects the first irradiated area 74a (S32). When the energy of the ion beam incident on the ion beam irradiated body 70 is located in the second energy region, the irradiated area selection unit 60 selects the second irradiated area 74b (S34). Thereafter, the ion beam IB irradiates the selected irradiated area 74 (S36). In this way, the present process ends.

[0142] In addition, the irradiated region selection unit 60 can determine whether the ion beam incident on the ion beam irradiated body 70 is an ion beam containing boron. When the energy of the boron ion beam is in the first energy range, the irradiated region selection unit 60 can select the first irradiated region 74a. When the energy of the boron ion beam is in the second energy range, the irradiated region selection unit 60 can select the second irradiated region 74b. When it is an ion beam that does not contain boron, the irradiated region selection unit 60 can select the first irradiated region 74a.

[0143] By distinguishing the irradiated areas according to energy, the occurrence of BC nuclear reactions is suppressed. As a result, during ultra-high energy ion implantation, the amount of radiation generated from the ion beam irradiated body 70 is reduced or virtually eliminated. The amount of radioactive nuclides generated is also reduced or virtually eliminated. Therefore, the control device 50 may not calculate the estimated amount of radiation and the estimated amount of radioactive nuclides generated for the first irradiated area 74a and the second irradiated area 74b. Alternatively, in order to ensure that the amount of radiation generated and the estimated amount of radioactive nuclides generated are sufficiently low, the control device 50 may only calculate the estimated amount of radiation and the estimated amount of radioactive nuclides generated for the second irradiated area 74b.

[0144] The present invention has been described above based on the embodiments. The present invention is not limited to the above embodiments, and it should be understood by those skilled in the art that various design changes and modifications can be made, and such modifications are also within the scope of the present invention.

[0145] So far, only the following has been mentioned about the BC reaction: 11 B is injected, but similar nuclear reactions occur in the stable isotope of boron. 10 It may also occur during the injection of B. 10 B and 12 The nuclear reaction of C is represented by the following formula.

[0146] 10 B+ 12 C→ 21 Na+n+kγ

[0147] 10 In the injection of B, it can also be applied 11 The injection of B is done with the same technique.

[0148] The embodiments of the present invention can also be expressed as follows.

[0149] 1. An ion implantation device, characterized in that it comprises:

[0150] an ion source configured to generate an ion beam containing ions of a first non-radioactive nuclide;

[0151] a beam line configured to support an ion beam irradiated object formed of a solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide; and

[0152] The control device is configured to calculate at least one of an estimated amount of radiation generated by a nuclear reaction between the first non-radioactive nuclide and the second non-radioactive nuclide and an estimated amount of radioactive nuclide generated.

[0153] 2. The ion implantation apparatus according to embodiment 1, characterized in that:

[0154] The first non-radioactive nuclide is 11 B or 10 B, the second non-radioactive nuclide is 12 C, the radiation is a neutron beam, and the radioactive nuclide is 22 Na or 21 Nah.

[0155] 3. The ion implantation apparatus according to embodiment 1 or 2, characterized in that:

[0156] An accelerator is further provided, which can accelerate the ion beam generated by the ion source to an ultra-high energy of at least 4 MeV.

[0157] 4. The ion implantation apparatus according to any one of embodiments 1 to 3, characterized in that:

[0158] The control device comprises:

[0159] a nuclear reaction rate calculation unit that calculates and estimates the nuclear reaction rate based on ion beam irradiation conditions including the energy of the ion beam and the irradiation amount per unit time and the atomic number density of the second non-radioactive nuclide in the irradiated area of ​​the ion beam irradiated body; and

[0160] The radiation dose calculation unit calculates an estimated radiation dose based on the estimated nuclear reaction rate.

[0161] 5. The ion implantation apparatus according to embodiment 4, characterized in that:

[0162] The control device includes a radionuclide generation amount calculation unit that calculates an estimated generation amount of the radionuclide based on the estimated nuclear reaction rate.

[0163] 6. The ion implantation apparatus according to any one of embodiments 1 to 5, characterized in that:

[0164] The control device is configured to display a warning and / or prohibit ion beam irradiation to the ion beam irradiated object when the estimated radiation dose exceeds a predetermined upper limit dose and / or when the estimated generation amount of the radioactive nuclides exceeds a predetermined upper limit value.

[0165] 7. The ion implantation apparatus according to any one of embodiments 1 to 6, characterized in that:

[0166] The ion beam irradiated body includes a base material and an irradiated region supported by the base material, wherein the irradiated region is formed of a solid material containing an element having an atomic number greater than that of the second non-radioactive nuclide.

[0167] 8. The ion implantation apparatus according to any one of embodiments 1 to 7, characterized in that:

[0168] The ion beam irradiated object has a plurality of irradiated areas located at different positions from each other.

[0169] The control device is configured to select any one of the plurality of irradiated areas so that the estimated radiation dose is lower than a predetermined upper limit dose.

[0170] The beam line includes a relative position adjustment mechanism configured to adjust a relative position between the ion beam irradiated object and the ion beam so that the ions of the first non-radioactive nuclide are incident on the selected irradiation region.

[0171] 9. The ion implantation apparatus according to any one of embodiments 1 to 8, characterized in that:

[0172] The ion beam irradiated object has a plurality of irradiated areas located at different positions from each other.

[0173] The control device is configured to select any one of the irradiated areas from the plurality of irradiated areas so that the estimated generation amount of the radioactive nuclides is less than a predetermined upper limit value.

[0174] The beam line includes a relative position adjustment mechanism configured to adjust a relative position between the ion beam irradiated object and the ion beam so that the ions of the first non-radioactive nuclide are incident on the selected irradiation region.

[0175] 10. The ion implantation apparatus according to any one of embodiments 1 to 7, characterized in that:

[0176] The ion beam irradiated body comprises: a first irradiated region formed of a first solid material containing the second non-radioactive nuclide; and a second irradiated region formed of a second solid material containing the second non-radioactive nuclide at a lower concentration than the first solid material or containing no second non-radioactive nuclide,

[0177] The control device is configured as follows: when the energy of the ion beam is in a first energy range, the first irradiated area is selected; when the energy of the ion beam is in a second energy range higher than the first energy range, the second irradiated area is selected;

[0178] The beam line includes a relative position adjustment mechanism configured to adjust a relative position between the ion beam irradiated object and the ion beam so that the ions of the first non-radioactive nuclide are incident on the selected irradiation region.

[0179] 11. The ion implantation apparatus according to embodiment 10, characterized in that:

[0180] The second solid material includes an element having an atomic number greater than that of the second non-radioactive nuclide.

[0181] 12. The ion implantation apparatus according to embodiment 10 or 11, characterized in that:

[0182] The second energy region is located in an ultra-high energy region of 4 MeV or more.

[0183] 13. The ion implantation apparatus according to any one of embodiments 1 to 12, characterized in that:

[0184] The ion beam irradiated object is constituted as a beam current measuring device provided in the beam line.

[0185] The control device calculates at least one of an estimated dose of the radiation and an estimated generation amount of the radionuclide based on the actual measured beam current measured by the beam current measuring device.

[0186] 14. The ion implantation apparatus according to any one of embodiments 1 to 13, characterized in that:

[0187] The ion beam irradiated object is configured as a beam deflector, an aperture plate, a beam shutter, a beam damper, a wafer support, or at least a part of a wafer.

[0188] 15. An ion implantation apparatus comprising:

[0189] an ion source configured to generate an ion beam containing ions of a first non-radioactive nuclide;

[0190] a beam line configured to support an ion beam irradiated object having a first irradiated region and a second irradiated region; and

[0191] The control device is configured as follows: when the energy of the ion beam is in a first energy range, the first irradiated area is selected; when the energy of the ion beam is in a second energy range higher than the first energy range, the second irradiated area is selected;

[0192] The beam line includes a relative position adjustment mechanism configured to adjust the relative position between the ion beam irradiated object and the ion beam in such a manner that the ions of the first non-radioactive nuclide are incident on the selected irradiated area.

[0193] The first irradiated area is formed of a first solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide,

[0194] The second irradiated region is formed of a second solid material that contains the second non-radioactive nuclide at a lower concentration than the first solid material or does not contain the second non-radioactive nuclide.

[0195] 16. An ion implantation method comprising:

[0196] The step of generating an ion beam comprising ions of a first non-radioactive nuclide;

[0197] a step of supporting an ion beam irradiated body formed of a solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide; and

[0198] A step of calculating at least one of an estimated amount of radiation generated by a nuclear reaction between the first non-radioactive nuclide and the second non-radioactive nuclide and an estimated amount of radioactive nuclide generated.

Claims

1. An ion implantation device, characterized in that: have: an ion source configured to generate an ion beam containing ions of a first non-radioactive nuclide; a beam line configured to support an ion beam irradiated object having a first irradiated region and a second irradiated region; and a control device configured to select the first irradiated area when the energy of the ion beam is in a first energy range, and to select the second irradiated area when the energy of the ion beam is in a second energy range higher than the first energy range, The beam line includes a relative position adjustment mechanism configured to adjust the relative position between the ion beam irradiated object and the ion beam in such a manner that the ions of the first non-radioactive nuclide are incident on the selected irradiated area. The first irradiated area is formed of a first solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide, The second irradiated region is formed of a second solid material that contains the second non-radioactive nuclide at a lower concentration than the first solid material or does not contain the second non-radioactive nuclide.

2. The ion implantation device according to claim 1, characterized in that: The first non-radioactive nuclide is 11 B or 10 B, the second non-radioactive nuclide is 12 C.

3. The ion implantation device according to claim 1 or 2, characterized in that: An accelerator is further provided, which is capable of accelerating the ion beam generated by the ion source to an ultra-high energy of at least 4 MeV.

4. The ion implantation device according to claim 1 or 2, characterized in that: The second irradiated region includes a base material and a surface layer portion supported by the base material, and the surface layer portion is formed of the second solid material.

5. The ion implantation device according to claim 1 or 2, characterized in that: The second solid material includes an element having an atomic number greater than that of the second non-radioactive nuclide.

6. An ion implantation device, characterized in that: have: A beam line configured to support an ion beam irradiated body having a first irradiated area allocated for an ion beam accelerated to a first energy range and a second irradiated area allocated for an ion beam accelerated to a second energy range higher than the first energy range; and a control device configured to select the first irradiated area when the energy of the ion beam incident on the ion beam irradiated body is in the first energy range, and to select the second irradiated area when the energy of the ion beam is in the second energy range, The beam line includes a relative position adjustment mechanism configured to adjust a relative position between the ion beam irradiated object and the ion beam so that the ion beam is incident on the selected irradiation region.

7. The ion implantation device according to claim 6, characterized in that: The second energy region is located in an ultra-high energy region of 4 MeV or more.

8. The ion implantation device according to any one of claims 1, 2, 6 and 7, characterized in that: The ion beam irradiated object is configured as a beam deflection device, an aperture plate, a beam shutter, a beam damper, a wafer support, or at least a part of a wafer, or is configured as at least a part of a beam current measuring device provided in the beamline.

9. An ion beam irradiated object, which is an ion beam irradiated object on a beam line of an ion implantation device, characterized in that: A plurality of irradiated areas are provided at different positions. The plurality of irradiated regions include a high-energy dedicated irradiated region that is allocated exclusively for a high-energy ion beam accelerated to an energy exceeding a predetermined energy threshold, The plurality of irradiation areas include a low-energy dedicated irradiation area that is allocated exclusively for a low-energy ion beam accelerated to an energy below a predetermined energy threshold. The ion implantation apparatus is configured to irradiate the ion beam irradiated object with an ion beam containing ions of a first non-radioactive nuclide. The low-energy dedicated irradiated area is formed of a first solid material containing a second non-radioactive nuclide different from the first non-radioactive nuclide, The high-energy dedicated irradiated region is formed of a second solid material that contains the second non-radioactive nuclide at a lower concentration than the first solid material or does not contain the second non-radioactive nuclide.

10. The object to be irradiated with an ion beam according to claim 9, characterized in that: The high-energy dedicated irradiated region includes a base material and a surface layer portion supported by the base material, and the surface layer portion is formed of the second solid material.

11. The object to be irradiated with an ion beam according to claim 9 or 10, characterized in that: The second solid material includes an element having an atomic number greater than that of the second non-radioactive nuclide.

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