JPH0365640B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electron wave ring that accumulates energy by accelerating charge electrons in orbit.

FIG. 1 is a schematic diagram showing the configuration of an example of a conventional electronic wave ring, with 1a to 1h having an orbital radius of 2 m,
Bending electromagnet with a deflection angle of 45°, 2 is a septum electromagnet for incidence, 3 is a Kitzker coil, 4 is a high frequency cavity, 5
is a quadrupole electromagnet (hereinafter referred to as
6 is a quadrupole electromagnet with horizontal focusing force (hereinafter referred to as Qf), 7 is the above-mentioned Qd6 as Qf5
This is a set of three triplets placed on both sides of the train. Note that 11 represents an electron orbit, and 12 represents an electron.
The operation will be described below with reference to the drawings.

The electron beam incident on the entrance septum electromagnet 2 passes through an entrance of only 8 mm x 10 mm square and is incident parallel to the stable electron orbit 11 at a position 40 mm outward from the stable orbit. The incident electrons 12 collide with the partition plate between the input septum electromagnet 2 and dissipate while making several rounds around the electron orbit 11, so an extreme pulse current synchronized with the electron beam is passed through the Kitzker coil 3 located half a turn downstream. Correct the electron trajectory 11.
Then, the electrons 12 are further accelerated and accumulated by the high frequency cavity 4 located 1/4 turn downstream, and the electron energy increases.

Next, the synchrotron radiation generated from the wave ring in Figure 1
The special SR product will be explained with reference to Figure 2.

In this figure, 11 is an electron orbit, and 12 is an electron accelerated in the electron orbit 11.

Synchrotron radiation SR is a diverging light source that has sharp directivity only in the direction perpendicular to the plane of the electron orbit 11 and is diffused in the tangential direction of the circular electron orbit 11.Since the irradiation angle is narrow, it cannot be used in wide-angle applications such as ring graphing technology. There was a problem in using it as a high-intensity light source with an illumination angle. Another disadvantage is that the electron beam cannot be stably moved vertically or horizontally at a constant speed with respect to a stable orbit.

The present invention has been made in consideration of the above points, and provides an electron wave ring that can stably move a charged particle beam at a constant speed in the horizontal and vertical directions and can generate high-intensity synchrotron radiation. The purpose is to

Hereinafter, this invention will be explained with reference to the drawings.

FIG. 3 is a schematic diagram showing the configuration of an electronic wave ring which is an embodiment of the present invention, and shows 1a to 1g, 2
7 and 11 and 12 are the same as in FIG.

In this figure, 21 is an undulator that converts parallel-transferred or deflected electrons into light, 22a is a vertical deflection electromagnet provided in the triplet 7, and 22
b is a horizontal deflection electromagnet also provided in the triplet 7. Hereinafter, the orbital deflection of the electron beam will be described in the order of vertical deflection and horizontal deflection.

First, in order to perform vertical deflection, Qd6-
A vertical deflection electromagnet 22a is provided between Qf5. The magnetic field of this vertical deflection electromagnet 22a (about several tens of Gauss)
As shown in Figure 4, the electron beam trajectory incident on Qf6 on the downstream side is amplified and deflected upward or downward by the vertical divergence force of Qf6, and is further deflected at a deflection angle of 45°. The light enters the electrode stone 1d (Fig. 3). The bending electromagnet 1d has an inclined incidence angle θ ₁ (11, 7°) as shown in Fig. 5a, and has a longitudinal focusing force as shown in Fig. 5b, so that it Alternatively, the incident electron beam deflected downward is corrected downward and upward, respectively, and passes through the bending electromagnet 1d, and the incident angle θ ₂ (11, 7 ) to correct the trajectory. Further, as shown in Fig. 6, the electron beam passing through the bending electromagnet 1d passes almost horizontally at a distance of dz cm vertically from the stable orbit, and passes through the bending electromagnets 1e to 1h on the downstream side while receiving the same longitudinal focusing force. pass. At that time, the electron beam incident on the downstream triplet 7 intersects the stable orbit at Qd5 of that triplet 7, and the upwardly deflected electron beam will be downwardly deflected, and the downwardly deflected electron beam will be upwardly deflected, as shown in Figure 6. As shown, a vertical wave motion is performed with the third bending electromagnets 1a and 1f, which are approximately centered on the vertical bending electromagnet 22a, serving as nodes. This vertically undulating electron beam enters an angierator 21 and emits light.

Next, stable movement of the electron beam in the horizontal direction will be explained. In order to perform horizontal deflection, the installation position of the horizontal deflection electromagnet 22b is the installation position of the vertical deflection electromagnet 22a or the downstream triplet 7.
between Qd5 and Qf6 on the downstream side of

Circumstances regarding the horizontal bending electromagnet 22b (more than 100 Gauss)
As shown in Figure 7, the trajectory of the electron beam incident on Qf6 on the downstream side is deflected to the left (inward) or right (outward), and is further deflected in the opposite direction by the horizontal focusing force of Qf6. The orbit is corrected in the direction, and the beam is horizontally incident on the bending magnet 1d at a distance of dxcm from the stable orbit to the left and right. However, the deviation of dxcm due to the inclined incidence angle θ ₁ (11, 7°) of the bending magnet 1d is the orbit radius in the magnetic field. The orbit of the electron beam stably moves outward or inward parallel to the stable orbit without significantly affecting R. Then, the electron beam is further horizontally focused by Qf6 located downstream.

Next, parallel control of the electron beam will be explained with reference to the excitation current waveform diagram in FIG. 8.

In this figure, the horizontal axis is time t, and the _vertical axis is exciting current I ₀ . The vertical bending electromagnet 22a and the horizontal bending electromagnet _22b in FIG _. Apply.

The electron beam is rotated at a constant speed for t ₀ seconds with respect to the Z axis and the X axis,
Displace dzcm, dxcm, stop for t ₁ second, then move at constant speed again
Displaced at a constant speed to −dzcm and −dxcm for t ₀ seconds, respectively,
t Control the excitation current I ₀ so that it returns to the original position after stopping for ₁ second.

Next, the structure and operation of the undulator 21 that emits the incident electron beam will be described with reference to FIGS. 9a to 9c.

FIG. 9a is a schematic diagram of the undulator 21, in which numeral 31 is a small permanent magnet, and magnets of different polarities are arranged alternately above and below. 32 is an electron beam, and λ ₀ is a period length.

Synchrotron radiation emitted from the undulator 21
When compared to the synchrotron radiation SR from a conventional storage ring, VR is synchrotron radiation with high brightness and quasi-monochromaticity 10 ² to 10 ³ times higher. As shown in FIG. 9b, the directivity of the synchrotron radiation SR is only in the direction perpendicular to the electron orbital plane, and it is a diverging light source that diffuses in the tangential direction of the circular orbit in the orbital plane. However, as shown in FIG. 9c, the emitted light VR from the undulator 21 is a emitted light with linear directivity in which electrons are emitted in a meandering manner. The relative brightness ratio between the synchrotron radiation VR and the synchrotron radiation SR is 2N<[VR]/[SR]< ^4N2 . N in the above formula is the number of cycles of the undulator 21. Here, the minimum value of the relative brightness ratio is equal to the number of antinodes of the meandering electron orbit, and the maximum value is the value when the interference effect of synchrotron radiation occurs at the antinodes where the directions of the electron beams are aligned. equal. Further, in the case of the permanent magnet undulator 21 using SmCO ₅ etc. as the magnetic material, the period length λ ₀ is about 3 to 4 cm, and if the period N at this time is 10, the synchrotron radiation VR
400 times the brightness is obtained compared to the synchrotron radiation SR, and if the period number N is 16, the synchrotron radiation VR has a brightness 1000 times as compared to the synchrotron radiation SR, and passes through the undulator 21 in this way. The electrons become highly bright light. Note that the undulator 21 is installed at a straight portion excluding the electron incidence part and the high frequency cavity due to the structure of the electron wave ring.

As explained in detail above, the present invention provides a high-intensity light source with a wider irradiation angle than conventional synchrotron radiation by using individual horizontal and vertical deflection electromagnets and undulators installed on the orbit of an electron wave ring. Furthermore, since the electron beam trajectory can be stably moved at a constant speed in the vertical and horizontal directions, it can be used in lithography technology, etc., and its industrial significance is extremely large.

[Brief explanation of drawings]

Figure 1 is a schematic diagram showing the configuration of a conventional electronic wave ring, and Figure 2 is a synchrotron radiation SR from the electron wave ring.
3 is a schematic configuration diagram showing an embodiment of the present invention, FIG. 4 is a diagram explaining the relationship between the vertical deflection electromagnet and the electron beam, and FIG. 5a is a plan view of the deflection electromagnet. Fig. 5b is a side view of the bending electromagnet, Fig. 6 is a wave characteristic diagram of the electron beam, Fig. 7 is a diagram explaining the relationship between the horizontal deflection electromagnet and the electron beam, Fig. 8 is an excitation current waveform diagram, FIG. 9a is a schematic diagram of the undulator, FIG. 9b is a diagram for explaining the directivity of the synchrotron radiation SR, and FIG. 9c is a diagram for explaining the directivity of the synchrotron radiation VR. In the figure, 1a to 1h are bending electromagnets, 2 is a septum electromagnet for incidence, 3 is a kicker coil, 4 is a high frequency cavity, 5 and 6 are quadrupole electromagnets, 7 is a triplet, 11 is an electron orbit, 12 is an electron, 21 is an undulator, 22a is a vertical deflection electromagnet, 22b is a horizontal deflection electromagnet, 31 is a small permanent magnet, 32 is an electron beam, and λ ₀ is a period length.

Claims (1)

[Scope of Claims] 1 A predetermined number of bending electromagnets are arranged at predetermined locations on the electron orbit, and between the deflection electromagnets, a high-frequency cavity and a triplet that focuses incident electrons in the horizontal and vertical directions are arranged on the electron orbit. In the electron wave ring provided at a predetermined position on the triplet to accumulate the incident electrons, deflection means is provided at a predetermined position of the triplet to stably move the incident electrons horizontally and vertically in parallel with a stable electron trajectory. An electronic wave ring characterized in that it is provided separately from each other and further includes an undulator that converts electrons deflected by the deflection means or moved in horizontal and vertical directions parallel to the stable orbit into optical energy. 2. The electron wave ring according to claim 1, wherein the deflection means stably and uniformly moves the electrons horizontally and vertically in parallel with a stable electron trajectory. 3. The electron wave ring according to claim 1, wherein the deflection means is provided in a straight portion of the electron orbit where the undulator and triplet are not installed.