Radiation source generating device

Abstract

To provide a radiation light source generator with excellent performance capable of achieving a high output function by applying a plurality of linear accelerators and reducing power consumption.SOLUTION: A synchrotron radiation source generating apparatus for emitting synchrotron radiation by accelerating an electron beam, comprising: an electron gun for emitting an electron beam; acceleration means arranged in parallel for continuously accelerating the electron beam emitted from the electron gun; a storage ring for storing the electron beam accelerated through the acceleration means; and an undulator for emitting synchrotron radiation from the electron beam stored in the storage ring.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a radiation source generator, and more particularly to a radiation source generator having excellent performance, which employs a plurality of linear accelerators to achieve high output capability and yet can reduce power consumption. [Background technology]

[0002] Extreme ultraviolet lithography (EUVL) is considered to be the most viable and cost-effective next-generation lithography for the sub-22nmHP (sub-7nm technology node) for high-volume manufacturing of semiconductor devices. EUVL is based on reflective optical components for both the projection optics and the mask.

[0003] The big step from state-of-the-art 193 nm (ArF (argon-fluorine)) optical lithography to 13.5 nm EUV lithography was triggered by the availability of optical elements for the EUV wavelength range. Compared to the 193 nm range, where refractive optics are used to manipulate the photon beam, only reflective optics can be used for the EUV range. Mo-Si coatings with 70% reflectivity and 2% BW at 13.5 nm wavelength are the technology of choice for both mirrors and masks. Such multilayers add another layer of complexity to the process. There are stringent requirements for the flatness of the optics and masks.

[0004] An EUV mask consists of a substrate, a multi-layer coating on the substrate, and an absorbing structure (e.g., TaN) patterned on the multi-layer, all of which may have some defects that need to be detected and characterized in order to repair the isolated defects or to discard the mask before it can be used in a scanner.

[0005] Therefore, EUV mask inspection tools become a critical element, especially for detecting phase errors caused by distortions located deep inside the multilayer mirror. Mask inspection is required on the blank multilayer, and through a pellicle on the patterned and final masks.

[0006] Although other metrology methods such as UV microscopy, AFM, SEM, etc. are used for this purpose, actinic mask inspection, i.e. metrology with EUV light, has proven to be an essential method, as only EUV light penetrates deeply into resonant multilayer structures.

[0007] The state-of-the-art SEMATECH Actinic Inspection Tool (SHARP) is a high-resolution EUV Fresnel zone plate microscope dedicated to photomask research.

[0008] Therefore, one of the main challenges for EUV metrology in the industry is to find a high brightness and high stability EUV source. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Korean Patent Registration No. 10-2038510 [Patent Document 2] U.S. Patent No. 8,941,336 Summary of the Invention [Problem to be solved by the invention]

[0010] In order to solve the above problems, an object of the present invention is to provide a synchrotron radiation source generator that can emit high-power synchrotron radiation while minimizing power consumption by designing a combination of an accelerator that accelerates the electron beam and a magnetic unit that controls the direction of the electron beam.

[0011] Another object of the present invention is to provide a radiation source generating apparatus having the structure according to the present invention, which can be installed and operated in a relatively small space by minimizing spatial restrictions.

[0012] In particular, the present invention provides a radiation source generating apparatus for generating EUV light for use in semiconductor manufacturing processes.

[0013] It is yet another object of the present invention to provide a radiation source generating apparatus that can be used to enhance or replace existing EUV radiation source apparatus. [Means for solving the problem]

[0014] In order to achieve the above objects, the present invention provides a radiation source generating apparatus that accelerates an electron beam and emits radiation, comprising: an electron gun that emits the electron beam; acceleration means arranged in parallel to continuously accelerate the electron beam emitted from the electron gun; a storage ring that stores the electron beam accelerated by the acceleration means; and an undulator that emits radiation from the electron beam stored in the storage ring.

[0015] Furthermore, when the electron beam emitted from the electron gun passes through a plurality of acceleration means, the acceleration means accelerates the electron beam by passing the electron beam through each of the acceleration means only once.

[0016] Furthermore, the acceleration means includes a plurality of linear accelerators arranged in a vertical direction in a plan view.

[0017] Furthermore, the acceleration means further comprises a magnetic section for redirecting and transmitting the electron beam from one linear accelerator to the next.

[0018] Furthermore, the acceleration means has each of the linear accelerators and the magnetic section connected in a one-way manner, so that the electron beam emitted from the electron gun is supplied to the storage ring.

[0019] Furthermore, the linear accelerator includes a 1-1 linear accelerator to which the electron beam emitted from the electron gun is first transmitted and accelerated, a 1-2 linear accelerator arranged opposite the 1-1 linear accelerator and to which the electron beam is transmitted, a 2-1 linear accelerator arranged side by side with the 1-1 linear accelerator and to which the electron beam is transmitted from the 1-2 linear accelerator, a 2-2 linear accelerator arranged side by side with the 1-2 linear accelerator and to which the electron beam is transmitted from the 2-1 linear accelerator, a 3-1 linear accelerator arranged side by side with the 2-1 linear accelerator and to which the electron beam is transmitted from the 2-2 linear accelerator, and a 3-2 linear accelerator arranged side by side with the 2-2 linear accelerator and to which the electron beam is transmitted from the 3-1 linear accelerator.

[0020] Furthermore, the magnetic unit includes a first magnetic unit that transmits the electron beam from the electron gun to one side of the first linear accelerator, a second magnetic unit that transmits the electron beam emitted from the other side of the first linear accelerator to the other side of the first linear accelerator, a second magnetic unit that transmits the electron beam emitted from the one side of the first linear accelerator to one side of the second linear accelerator, and a third magnetic unit that transmits the electron beam emitted from the other side of the second linear accelerator to the other side of the second linear accelerator. a 2-1-2 magnetic section that transmits the electron beam extracted from one side of the 2-2 linear accelerator to the other side of the 3-1 linear accelerator; a 2-2-2 magnetic section that transmits the electron beam extracted from one side of the 2-2 linear accelerator to one side of the 3-1 linear accelerator; a 2-1-3 magnetic section that transmits the electron beam extracted from the other side of the 3-1 linear accelerator to the other side of the 3-2 linear accelerator; and a third magnetic section that transmits the electron beam extracted from one side of the 3-2 linear accelerator to the storage ring.

[0021] Furthermore, the magnetic unit includes a first magnetic unit that transmits the electron beam emitted from the electron gun to the linear accelerator with the highest priority, a plurality of second magnetic units that transmit the electron beam from one linear accelerator to the next, and a third magnetic unit that emits the electron beam from the final linear accelerator to the storage ring.

[0022] Furthermore, the magnetic section is composed of a combination of a dipole magnet and a quadrupole magnet to transmit the electron beam that has passed through one of the linear accelerators to the next linear accelerator.

[0023] Furthermore, the two-pole magnet and the four-pole magnet provide a magnetic field to the permanent magnet.

[0024] Furthermore, the acceleration means is configured to be located inside the storage ring.

[0025] Furthermore, the magnetic section is composed of a quadrupole magnet, a quadrupole magnet, a dipole magnet, a quadrupole magnet, a dipole magnet, a quadrupole magnet, and a quadrupole magnet, in that order, to transmit the electron beam from one linear accelerator to the next.

[0026] Furthermore, the acceleration means has a plurality of linear accelerators arranged in a stacked structure in a plan view.

[0027] Furthermore, the two-pole magnet is configured with a control coil so that the minute strength of the magnetic field can be controlled by supplying a current thereto.

[0028] Furthermore, the control coil controls the magnetic field strength at around 5% of the magnetic field strength.

[0029] Furthermore, the two-pole magnet and the four-pole magnet are configured so that the minute strength of the magnetic field can be adjusted by controlling the drive motor.

[0030] In addition to these, the undulator emits EUV light. [Effects of the Invention]

[0031] The present invention configured and operated as described above has an advantage that a stable high-power radiation source can be generated by preferentially using only a plurality of linear accelerators.

[0032] In addition, the present invention has the advantage that a synchrotron radiation source can be realized with minimal power consumption by using only permanent magnets for the magnetic section that controls the direction of the electron beam while applying multiple linear accelerators and by not using a booster ring, which is a conventional technology that uses electromagnets.

[0033] Furthermore, the radiation light source device according to the present invention is designed to minimize the installation space in order to overcome the drawbacks of radiation light source devices based on existing accelerators, which have been considered problematic due to space limitations. [Brief explanation of the drawings]

[0034] [Figure 1] 1 is a diagram showing the overall configuration of a radiation source generating apparatus according to the present invention; [Figure 2] FIG. 2 is a detailed configuration diagram of an acceleration means in the radiation source generating device according to the present invention. [Figure 3] FIG. 2 is a detailed configuration diagram of a linear accelerator in the radiation source generating device according to the present invention. [Figure 4] FIG. 2 is a configuration diagram of a magnetic section in the radiation source generating device according to the present invention. [Figure 5] FIG. 2 is a detailed configuration diagram of a magnetic section in the radiation source generating device according to the present invention. [Figure 6] FIG. 2 is a diagram showing the configuration of a storage ring in a radiation source generating apparatus according to the present invention. [Figure 7] FIG. 10 is a configuration diagram showing another embodiment of the magnetic section according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0035] The radiation source generating apparatus according to the present invention will be described in detail below with reference to the accompanying drawings.

[0036] The radiation source generator according to the present invention accelerates an electron beam to emit synchrotron radiation, and comprises an electron gun that emits the electron beam, acceleration means arranged in parallel to continuously accelerate the electron beam emitted from the electron gun, a storage ring that stores the electron beam accelerated by the acceleration means, and an undulator that emits synchrotron radiation from the electron beam stored in the storage ring.

[0037] The main technical feature of the radiation source generator according to the present invention is that it uses multiple linear accelerators to accelerate electron beams, and uses a magnetic unit based on permanent magnets to connect the multiple linear accelerators to each other, thereby eliminating the power consumption caused by the use of electromagnets used in existing radiation source generators, and the magnetic unit can be composed of only permanent magnets.

[0038] FIG. 1 is a diagram showing the overall configuration of a radiation source generating apparatus according to the present invention.

[0039] The radiation source generator 10 according to the present invention comprises an electron gun 100 that emits an electron beam, an acceleration means 200 that accelerates the electron beam emitted from the electron gun 100 to generate an electron beam having a desired energy, a storage ring 300 that stores the electron beam accelerated by the acceleration means 200, and an undulator 400 that emits radiation from the electron beam stored in the storage ring.

[0040] Preferably, the radiation source generating device 10 according to the present invention corresponds to a radiation source device that generates EUV light, and the EUV light generated here is preferably applied to semiconductor processes.

[0041] FIG. 2 is a detailed structural diagram of the acceleration means of the radiation source generating apparatus according to the present invention.

[0042] The acceleration means 200 according to the present invention is broadly composed of a plurality of linear accelerators 210 and a plurality of magnetic units 220 for connecting and transmitting electron beams accelerated in the plurality of linear accelerators 210 to each other.

[0043] In other words, the electron beam first emitted from the electron gun 100 passes through one linear accelerator and is then transmitted to the next linear accelerator via one of the magnetic units 220. The electron beam that has passed through the linear accelerator again is transmitted via a magnetic unit to be transmitted to the next linear accelerator.

[0044] In the present invention, a structure is provided in which a plurality of linear accelerators are arranged in a parallel configuration, and an electron beam is transmitted on both sides of the parallel linear accelerators via a plurality of magnetic units 220. Such a structure can efficiently accelerate an electron beam via a plurality of linear accelerators within a limited space.

[0045] FIG. 3 is a detailed configuration diagram of the linear accelerator of the radiation source generating apparatus according to the present invention.

[0046] FIG. 3 shows in detail a linear accelerator with a parallel structure corresponding to the main technical subject of the present invention.

[0047] According to one embodiment of the present invention, the linear accelerator 210 has a structure in which, in plan view, three linear accelerators are arranged in parallel on the lower side and three linear accelerators are arranged in parallel on the upper side.

[0048] Specifically, the electron beam emitted from the electron gun is first transmitted to and accelerated by a first linear accelerator 211; a first linear accelerator 212 disposed opposite the first linear accelerator 211 and receiving the electron beam; a second linear accelerator 213 disposed outside the first linear accelerator 211 and receiving the electron beam from the first linear accelerator 212; The accelerator is composed of a second linear accelerator 214 arranged side by side and receiving an electron beam from the second linear accelerator 213, a third linear accelerator 215 arranged side by side on the outside of the second linear accelerator 213 and receiving an electron beam from the second linear accelerator 213, and a third linear accelerator 216 arranged side by side on the outside of the second linear accelerator 214 and receiving an electron beam from the third linear accelerator 215.

[0049] At both ends of the linear accelerators 210 arranged in parallel, the electron beam accelerated by the coupling of the magnetic sections is transmitted to the next linear accelerator, and the electron beam emitted from the electron gun passes through the multiple acceleration means consisting of the linear accelerator and magnetic sections only once, is accelerated, and then stored in the storage ring.

[0050] In other words, the acceleration means 200 supplies the electron beam emitted from the electron gun to the storage ring by connecting the linear accelerator 210 and the magnetic unit 220 in a one-way configuration.

[0051] FIG. 4 is a configuration diagram of a magnetic section in a radiation source generating apparatus according to the present invention.

[0052] As described above, the magnetic section 220 connects the linear accelerators to each other and transmits the electron beam.

[0053] First, there is a first magnetic section 221 that transmits the electron beam from the electron gun 100 to one side of the first linear accelerator, a second magnetic section 222 that transmits the electron beam emitted from the other side of the first linear accelerator to the other side of the first linear accelerator, a second magnetic section 223 that transmits the electron beam emitted from the one side of the first linear accelerator to one side of the second linear accelerator, and a third magnetic section 224 that transmits the electron beam emitted from the other side of the second linear accelerator to the second linear accelerator. a second-1-2 magnetic section 224 for transmitting the electron beam extracted from one side of the second-2 linear accelerator to the other side of the third-1 linear accelerator; a second-2-2 magnetic section 225 for transmitting the electron beam extracted from one side of the second-2 linear accelerator to one side of the third-1 linear accelerator; a second-1-3 magnetic section 226 for transmitting the electron beam extracted from the other side of the third-1 linear accelerator to the other side of the third-2 linear accelerator; and a third magnetic section 227 for transmitting the electron beam extracted from one side of the third-2 linear accelerator to the storage ring.

[0054] FIG. 5 is a detailed configuration diagram of a magnetic section in a radiation source generating apparatus according to the present invention.

[0055] In the present invention, a quadrupole magnet 230 and a dipole magnet 231 are combined to form one magnetic section 220. Each of the magnetic sections 222, 224, and 226 according to the present invention is formed by combining a quadrupole magnet and a dipole magnet. Specifically, the magnetic section is formed by combining a quadrupole magnet, a dipole magnet, a quadrupole magnet, a dipole magnet, a quadrupole magnet, a quadrupole magnet, and a quadrupole magnet in this order to form an achromatic bend.

[0056] In the present invention, depending on the purpose, the magnetic field is constructed only from permanent magnets without using an electromagnet-type magnetic part or a booster ring, thereby minimizing power consumption in the entire radiation source generating device.

[0057] Two dipole magnets 231 for each magnetic section serve to deflect the electron beam trajectory by 90° each, and the central quadrupole magnet 230 is configured to correct the horizontal dispersion (η) that can occur due to the difference in angle at which electrons with different kinetic energies in the electron beam are deflected by the dipole magnets.

[0058]

number

[0059] △x: horizontal beam spread, △E: beam energy spread, η: dispersion (correlation coefficient between beam energy and beam spread)

[0060] The four outer quadrupole magnets are magnets for adjusting the horizontal beta function of the electron beam. The beta function describes the beam size, and the horizontal beta function

[0061]

number

[0062] 6 is a diagram showing the configuration of a storage ring in a synchrotron radiation source according to the present invention. The storage ring 300 used in the present invention is located at the outermost periphery of the entire synchrotron radiation source system. The electron beam accelerated by the accelerator passes through a storage ring accelerating tube 410 and a storage ring injection kicker 420 located in the storage ring and is then stored in the storage ring.

[0063] FIG. 7 is a configuration diagram showing another embodiment of the magnetic section according to the present invention.

[0064] The magnetic section configured in the present invention is configured to control the direction of the accelerated electron beam by applying a permanent magnet, and may also be provided with a control coil for finely controlling the trajectory of the electron beam in order to design the entire radiation source device, or for finely controlling the magnetic field so as to accurately control the phenomenon in which electrons with different kinetic energies in the electron beam are deflected by a bipole magnet.

[0065] In this case, the two-pole magnet 231 configured in the magnetic section is provided with a control coil 250 so that it can supply current to control the minute strength of the magnetic field, and the control coil 250 controls the magnetic field strength to around 5% of the magnetic field strength.

[0066] In addition, in the present invention, a separate driving motor 260 is applied to the two-pole magnet and the four-pole magnet to move a part of the yoke of the permanent magnet, thereby enabling fine control of the magnetic field strength.

[0067] The present invention configured in this manner has the advantage that a stable high-power radiation source can be generated by preferentially using only a plurality of linear accelerators.

[0068] In addition, the present invention has the advantage that a synchrotron radiation source can be realized with minimal power consumption by using only permanent magnets for the magnetic section that controls the direction of the electron beam while applying multiple linear accelerators and by not using a booster ring, which is a conventional technology that uses electromagnets.

[0069] Furthermore, the radiation light source device according to the present invention is designed to minimize the installation space in order to overcome the drawbacks of radiation light source devices based on existing accelerators, which have been considered problematic due to space limitations.

[0070] While the present invention has been described and illustrated in connection with preferred embodiments for the purpose of illustrating the principles of the present invention, it is not intended that the present invention be limited to the exact construction and operation so shown and described. Rather, it will be apparent to those skilled in the art that numerous changes and modifications can be made to the present invention without departing from the spirit and scope of the appended claims. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention. [Explanation of symbols]

[0071] 10: Synchrotron radiation source generator 100:Electron gun 200: Acceleration means 210: Linear accelerator 220: Magnetic section 260: Drive motor 300: Storage Ring 400: Undulator

Claims

1. In a radiation source generating apparatus that accelerates an electron beam and emits radiation, an electron gun that emits an electron beam; Acceleration means arranged in parallel for continuously accelerating the electron beam emitted from the electron gun; a storage ring for storing the electron beam accelerated by the acceleration means; an undulator that emits synchrotron radiation from the electron beam stored in the storage ring; A radiation source generating device comprising:

2. The acceleration means 2. The radiation source generating apparatus according to claim 1, wherein when the electron beam emitted from said electron gun passes through a plurality of accelerating means, the electron beam is accelerated by passing through each of said accelerating means only once.

3. The acceleration means 3. The radiation source generating apparatus according to claim 2, further comprising a plurality of linear accelerators arranged in a vertical direction in a plan view to accelerate the electron beam.

4. The acceleration means 4. The radiation source generator of claim 3, further comprising a magnetic section for redirecting and transmitting the electron beam from one linear accelerator to the next.

5. The acceleration means 5. The radiation source generating apparatus according to claim 4, wherein each of the linear accelerators and the magnetic section is connected in a one-way manner so that the electron beam emitted from the electron gun is supplied to the storage ring.

6. The linear accelerator comprises: a first linear accelerator (1-1) to which the electron beam emitted from the electron gun is first transmitted and accelerated, and a second linear accelerator (1-2) disposed opposite the first linear accelerator and to which the electron beam is transmitted; a second-first linear accelerator arranged side by side with the first-first linear accelerator and receiving an electron beam from the first-second linear accelerator; a second-second linear accelerator arranged side by side with the first-second linear accelerator and receiving an electron beam from the second-first linear accelerator; a third-1 linear accelerator arranged side by side with the second-1 linear accelerator and receiving an electron beam from the second-2 linear accelerator; and a third-2 linear accelerator arranged side by side with the second-2 linear accelerator and receiving an electron beam from the third-1 linear accelerator; 6. The radiation source generating apparatus of claim 5, comprising:

7. The magnetic portion is 7. The radiation source generator according to claim 6, further comprising: a first magnetic section that transmits the electron beam emitted from the electron gun to a linear accelerator with the highest priority; a plurality of second magnetic sections that transmit the electron beam from one linear accelerator to the next; and a third magnetic section that emits the electron beam from a final linear accelerator to a storage ring.

8. The magnetic portion is a first magnetic section for transmitting the electron beam from the electron gun to one side of the first linear accelerator; a second-first-first magnetic unit that transmits the electron beam emitted from the other side of the first-first linear accelerator to the other side of the first-second linear accelerator; a second-2-1 magnetic unit that transmits the electron beam emitted from one side of the first-2 linear accelerator to one side of the second-1 linear accelerator; a second-1-2 magnetic unit that transmits the electron beam emitted from the other side of the second-1 linear accelerator to the other side of the second-2 linear accelerator; a second-2-2 magnetic unit that transmits the electron beam emitted from one side of the second-2 linear accelerator to one side of the third-1 linear accelerator; a second-first-third magnetic unit that transmits the electron beam emitted from the other side of the third-first linear accelerator to the other side of the third-second linear accelerator; a third magnetic section for transmitting the electron beam emitted from one side of the third-2 linear accelerator to the storage ring; 8. The radiation source generating apparatus according to claim 7, comprising:

9. The magnetic portion is 9. The radiation source generating apparatus according to claim 8, which is configured by a combination of a dipole magnet and a quadrupole magnet to transmit the electron beam that has passed through one of said linear accelerators to the next linear accelerator.

10. The two-pole magnet and the four-pole magnet are 10. A source generator as claimed in claim 9, wherein the magnetic field is provided to a permanent magnet.

11. The acceleration means 4. A radiation source generating apparatus according to claim 1, configured to be located inside the storage ring.

12. The magnetic portion is 8. The radiation source generating apparatus according to claim 7, comprising an achromatic bend in which a quadrupole magnet, a quadrupole magnet, a dipole magnet, a quadrupole magnet, a dipole magnet, a quadrupole magnet, and a quadrupole magnet are combined in this order to transmit an electron beam from one linear accelerator to the next.

13. The acceleration means 4. The radiation source generator according to claim 3, wherein a plurality of linear accelerators are arranged in a stacked structure in a plan view.

14. The two-pole magnet and the four-pole magnet are 13. A radiation source generating apparatus according to claim 10 or 12, wherein the control coil is configured to supply a current thereto to control the minute strength of the magnetic field.

15. The control coil 15. The radiation source generating apparatus according to claim 14, wherein the magnetic field strength is controlled to be around 5% of the magnetic field strength.

16. The two-pole magnet and the four-pole magnet are 13. The radiation source generating device according to claim 10, wherein the minute intensity of the magnetic field can be adjusted by controlling a drive motor.

17. The undulator is 2. The radiation source generating device according to claim 1, which emits extreme ultraviolet (EUV) light.

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