Emitter

Abstract

To provide an electron source with an excellent position stability of an electron source chip in use, and provide a manufacturing method of the same.SOLUTION: An emitter includes: an electron source chip; a first filament connected to a first position of a side surface of the electron source chip; a second filament that is connected to a second position of the side surface of the electron source chip; two upper part positive terminals to which two first side surfaces of the first filament are connected, respectively; two upper part negative terminals to which two second side surfaces of the second filament are connected, respectively; one lower part positive terminal that is electrically connected to the two upper part positive terminals; one lower part negative terminal that is electrically connected to the two upper part negative terminals; and an insulator that carriers the upper part positive terminal, the upper part negative terminal, the lower part positive terminal, and the lower part negative terminal. The first position and the second position are different from each other. The first side surfaces of the first filament are connected to the side surfaces of the upper part positive terminals respectively, and the second side surfaces of the second filament are connected to the side surfaces of the upper part negative terminals respectively.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an emitter. [Background technology]

[0002] Electron sources are used in a variety of devices, such as electron beam lithography devices, electron beam writing devices, multi-electron beam systems, scanning electron microscopes (SEMs), transmission electron microscopes (TEMs), electron beam microanalyzers, and microfocus X-ray devices.

[0003] For example, in Patent Document 1, a tungsten or molybdenum-made electron source having an electron emission surface with an exposed {100} crystal face at the tip is disclosed, which is intended to provide an electron source that operates stably for a long period of time. <100> a metal oxide layer covering the {100} crystal faces; and a diffusion source for diffusing a source material of the metal oxide layer; <100> An electron source is disclosed that includes a passage formed in an oriented single crystal rod, communicating from a diffusion source to the tip or near the tip, and providing a path for diffusion of source material from the diffusion source.

[0004] In the case of a structure in which an electron source tip is connected to a single filament, such as the emitter shown in Patent Document 1, the position of the electron source changes little by little when voltage is applied, and the change in the position of the electron source tip may result in a decrease in processing accuracy, etc.

[0005] Furthermore, Patent Document 2 discloses an electron gun having a multifilament heater composed of a first filament connected to two positive terminals and a second filament connected to two negative terminals, with the aim of providing an electron gun that is less susceptible to magnetic misalignment. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2011-065790 A [Patent Document 2] US2022-0076914A Summary of the Invention [Problem to be solved by the invention]

[0007] As in Patent Document 2, by using a multifilament heater structure, it is theoretically possible to suppress misalignment due to magnetism. However, if each filament is arranged on the upper surface of the terminal, the contact points between the filament and the terminal are small and fragile, making it difficult to suppress misalignment due to magnetism for a long period of time.

[0008] Also, Patent Document 2 shows an embodiment having four upper terminals, and it is presumed that the number of lower terminals in this embodiment is also four. However, some devices that utilize emitters correspond to two lower terminals, so a new structure with two lower terminals and four upper terminals is required.

[0009] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide an electron source having excellent positional stability of the electron source tip during use, and a manufacturing method thereof. [Means for solving the problem]

[0010] That is, the present invention is as follows. [1] An electron source chip; a first filament connected to a first position on a side of the electron source tip; a second filament connected to a second location on a side of the electron source tip; two upper positive terminals to which the two first side surfaces of the first filament are respectively connected; two upper negative terminals to which the two second side surfaces of the second filament are respectively connected; a lower positive terminal electrically connected to the two upper positive terminals; a lower negative terminal electrically connected to the two upper negative terminals; an insulator carrying the upper positive terminal, the upper negative terminal, the lower positive terminal, and the lower negative terminal; the first position and the second position are different positions; the first side of the first filament is connected to a side of the upper positive terminal, the second side of the second filament is connected to a side of the upper negative terminal, Emitter. [2] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, The two upper positive terminals and the two upper negative terminals are arranged such that a line segment connecting the centers of the two upper positive terminals intersects with a line segment connecting the centers of the two upper negative terminals. The emitter described in [1]. [3] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, The first filament and the second filament are arranged to cross each other. The emitter according to [1] or [2]. [4] In a plan view of the first surface, The angle θ1 between the projection lines of the first filament and the second filament is 80° or more and 90° or less. The emitter according to [3]. [5] In a plan view of the first surface, The angle θ1 between the projection lines of the first filament and the second filament is less than 80°. The emitter according to [3]. [6] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament is disposed such that a line segment connecting the side surfaces of the two upper positive terminals to which the first side surface of the first filament is connected intersects with a line segment connecting the centers of the two upper positive terminals. The emitter according to any one of [1] to [5]. [7] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the second filament is disposed such that a line segment connecting the side surfaces of the two upper negative terminals to which the second side surface of the second filament is connected intersects with a line segment connecting the centers of the two upper negative terminals. The emitter according to any one of [1] to [6]. [8] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament is disposed such that a line segment connecting the side surfaces of the two upper positive terminals to which the first side surface of the first filament is connected does not intersect with a line segment connecting the centers of the two upper positive terminals. The emitter according to any one of [1] to [5] and [7]. [9] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the second filament is disposed such that a line segment connecting the side surfaces of the two upper negative terminals to which the second side surface of the second filament is connected does not intersect with a line segment connecting the centers of the two upper negative terminals. The emitter according to any one of [1] to [6] and [8].

[10] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament and the second filament are arranged such that the side of the upper positive terminal to which the first side surface of the first filament is connected faces at least the side of the upper negative terminal to which the second side surface of the second filament is connected. The emitter according to any one of [1] to [9].

[11] In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament and the second filament are arranged such that the side of the upper positive terminal to which the first side surface of the first filament is connected does not face the side of the upper negative terminal to which the second side surface of the second filament is connected. The emitter according to any one of [1] to [9].

[12] the first filament is joined at a position closer to the tip of the electron source tip than the second filament; The emitter according to any one of [1] to

[11] .

[13] the second filament is joined at a position closer to the tip of the electron source tip than the first filament; The emitter according to any one of [1] to

[11] .

[14] The pair of upper positive terminals each have a positive terminal connection portion that electrically connects the pair of upper positive terminals, The pair of upper negative terminals have negative terminal connection portions that electrically connect the pair of upper negative terminals. The emitter according to any one of [1] to

[13] . Effect of the Invention

[0011] According to the present invention, it is possible to provide an emitter having excellent positional stability of the electron source tip during use. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a schematic perspective view of an emitter according to the present embodiment. [Diagram 2] FIG. 2 is a top view of the insulator as viewed from the electron source tip side on a first surface perpendicular to the front end direction of the electron source tip. [Figure 3A] FIG. 2 is a top view of the insulator as viewed from the electron source tip side on a first surface perpendicular to the front end direction of the electron source tip. [Figure 3B]FIG. 2 is a top view of the insulator as viewed from the electron source tip side on a first surface perpendicular to the front end direction of the electron source tip. [Figure 4] FIG. 2 is a top view of the insulator as viewed from the electron source tip side on a first surface perpendicular to the front end direction of the electron source tip. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings as necessary, but the present invention is not limited to this embodiment, and various modifications are possible without departing from the gist of the present invention. Note that the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0014] In this embodiment, the "X direction", "Y direction", "Z direction", and "XY plane direction" are specified as necessary. Here, the "Z direction" is a direction parallel to the direction in which the electron source is emitted from the tip of the electron source tip 10. The direction in which electrons are emitted from the tip of the electron source tip 10 is also called the "Z+ direction", and the direction opposite to the Z+ direction is also called the "Z- direction". In addition, unless otherwise specified, the "Z direction" is parallel to the extension direction of the upper terminal 20 and the lower terminal 30.

[0015] The "XY plane direction" is a plane direction that intersects with the Z direction. The XY plane direction may be parallel to the surface 40a from which the upper terminal 20 of the insulator 40 extends and the surface 40b from which the lower terminal 30 extends. Unless otherwise specified, the Z direction may be perpendicular to the XY plane direction. The "X direction" and the "Y direction" are directions that intersect with each other in the XY plane. The "X direction" refers to the direction connecting the centers of the upper positive terminals 20a, 20b, and the "Y direction" refers to the direction connecting the centers of the upper negative terminals 20c, 20d. The X direction and the Y direction do not have to be perpendicular to each other.

[0016] Terms that mean shapes and / or geometric conditions do not need to be bound by strict meanings and may be interpreted to include a range within which similar functions may be expected. For example, "parallel" and / or "orthogonal" fall under the above terms.

[0017] When a certain configuration is expressed as being "above," "below," "upper," "lower," "above," or "below" another configuration, this may include a configuration in which the certain configuration is in direct contact with the other configuration, and a configuration in which another configuration is included between the certain configuration and the other configuration. In other words, a configuration in which another configuration is included between the certain configuration and the other configuration may be expressed as a configuration indirectly in contact with the other configuration. Furthermore, the expressions "above," "upper side," or "above" can be exchanged for the expressions "below," "lower side," or "below." In other words, the up-down direction may be reversed. The same applies to the left and right.

[0018] When the same or similar symbols are used for the same parts and / or parts having similar functions, repeated description may be omitted. In addition, the dimensional ratios in the drawings may differ from the actual ratios. In addition, part of the configuration of the embodiment may be omitted from the drawings.

[0019] FIG. 1 shows an emitter 1 of this embodiment. As shown in FIG. 1, the emitter 1 of this embodiment includes an electron source chip 10, a first filament 50 connected to a first position 10a on a side of the electron source chip 10, a second filament 60 connected to a second position 10b on a side of the electron source chip 10, two upper positive terminals 20a, 20b to which the two first side surfaces 50a, 50b of the first filament 50 are respectively connected, two upper negative terminals 20c, 20d to which the two second side surfaces 60a, 60b of the second filament are respectively connected, one lower positive terminal 30a electrically connected to the two upper positive terminals 20a, 20b, one lower negative terminal 30b electrically connected to the two upper negative terminals 20c, 20d, and an insulator 40 supporting the upper positive terminals 20a, 20b, the upper negative terminals 20c, 20d, the lower positive terminal 30a, and the lower negative terminal 30b.

[0020] The upper positive terminals 20a, 20b and the upper negative terminals 20c, 20d are collectively referred to as "upper terminals 20." The lower positive terminal 30a and the lower negative terminal 30b are collectively referred to as "lower terminals 30." Each component of the emitter 1 of this embodiment will be described in more detail below.

[0021] The electron source tip 10 is made of a material that emits electrons when heated and an electric field is applied, and may have an electron emission surface at its tip that emits electrons. The electron emission material is not particularly limited, but examples thereof include tungsten, molybdenum, tantalum, rhenium, LaB 6 Lanthanum borides such as CeB 6 Cerium borides such as Ir 2 and iridium cerium such as Ce.

[0022] The electron source tip may also have a diffusion source 11. The diffusion source 11 is not particularly limited, but may be, for example, a composite oxide of barium oxide or scandium oxide.

[0023] The first filament 50 and the second filament 60 are connected to the electron source chip 10 as filaments for heating the electron source chip 10. More specifically, the first filament 50 and the second filament 60 may be connected to a heating power source via the upper terminal 20 and the lower terminal 30, and the electron source chip 10 may be heated by a current flowing from the heating power source. The current flowing through the first filament 50 and the second filament 60 may be set so that the electron source is, for example, about 1800K.

[0024] FIG. 1 shows an embodiment in which the first filament 50 is joined at a position closer to the tip of the electron source tip 10 than the second filament 60, but this is not limited thereto, and the second filament 60 may be joined at a position closer to the tip of the electron source tip 10 than the first filament 50.

[0025] The distance between a first position 10a on a side of the electron source chip 10 to which the first filament 50 is connected and a second position 10b on a side of the electron source chip 10 to which the second filament 60 is connected is preferably 10 to 500 μm, and may be 50 to 300 μm. Note that this distance refers to the gap distance between the first filament 50 and the second filament 60.

[0026] Furthermore, tungsten or graphite filaments, carbon heaters, etc. may be used as the first filament 50 and the second filament 60. Furthermore, the materials constituting the first filament 50 and the second filament 60 may be the same or different.

[0027] The first filament 50 has its first side surfaces 50a, 50b connected to the two upper positive terminals 20a, 20b, respectively, and an arbitrary portion between the first side surfaces 50a, 50b is connected to a first position 10a on the side surface of the electron source chip 10. The second filament 60 has its second side surfaces 60a, 60b connected to the two upper negative terminals 20c, 20d, respectively, and an arbitrary portion between the second side surfaces 60a, 60b is connected to a second position 10b on the side surface of the electron source chip 10.

[0028] 1, in the emitter 1 of this embodiment, two upper positive terminals 20a, 20b are electrically connected to one lower positive terminal 30a, and two upper negative terminals 20c, 20d are electrically connected to one lower negative terminal 30b. Thus, the emitter 1 has a structure in which two lower terminals 30 are converted into four upper terminals 20.

[0029] The manner in which the two upper positive terminals 20a, 20b and the single lower positive terminal 30a are connected is not particularly limited, and examples thereof include a manner in which the two upper positive terminals 20a, 20b are each connected to the lower positive terminal 30a; as shown in FIG. 1, a manner in which the single upper positive terminal 20b is connected to the lower positive terminal 30a, and the upper positive terminal 20a and the upper positive terminal 20b are linked together, and the like.

[0030] Here, the connection portion between the upper positive terminals 20a, 20b and the lower positive terminal 30a is referred to as the upper and lower positive terminal connecting portion 80a, and the connecting portion electrically connecting the pair of upper positive terminals 20a, 20b is referred to as the upper positive terminal connecting portion 81a.

[0031] The manner in which the two upper negative terminals 20c, 20d and the single lower negative terminal 30b are connected is not particularly limited, but examples include a manner in which the two upper negative terminals 20c, 20d are each connected to the lower negative terminal 30b; as shown in Figure 1, a manner in which the single upper negative terminal 20c is connected to the lower negative terminal 30b, and the upper negative terminal 20c and the upper negative terminal 20d are linked together; and the like.

[0032] Here, the connection portion between upper negative terminals 20c, 20d and lower negative terminal 30b is referred to as upper and lower negative terminal connection portion 80b, and the connection portion electrically connecting the pair of upper negative terminals 20c, 20d is referred to as upper negative terminal connection portion 81b.

[0033] In the example shown in FIG. 1, the upper positive terminal connecting portion 81a is located on the Z+ direction surface of the insulator 40, and the upper negative terminal connecting portion 81b is located inside the insulator 40, but this is not limited to this, and in addition to the upper positive terminal connecting portion 81a, the upper negative terminal connecting portion 81b may also be located on the Z+ direction surface of the insulator 40 so as to bypass the upper positive terminal connecting portion 81a and the upper positive terminals 20a, 20b.

[0034] With the above structure, during heating, electrons are supplied from the lower negative terminal 30b to the two upper negative terminals 20c, 20d, and then from the second side surfaces 60a, 60b of the second filament 60 toward the second position 10b on the side surface of the electron source chip 10. Then, electrons flow from the first position 10a on the side surface of the electron source chip 10 toward the first side surfaces 50a, 50b of the first filament 50, and then from the upper positive terminals 20a, 20b to the lower positive terminal 30a.

[0035] The emitter 1 of this embodiment has a structure in which a filament is stretched across two upper positive terminals 20a, 20b and two upper negative terminals 20c, 20d, and the two filaments support the electron source tip 10. Therefore, the electron source tip is held more stably than in a structure in which the electron source tip 10 is supported by one filament with a positive terminal and a negative terminal connected.

[0036] The electron gun comprises a magnetic lens that forms a magnetic field, and an emitter 1. This allows electrons to be emitted from the tip of the emitter 1 through the magnetic lens toward the target. At this time, the emitter 1 is placed within the magnetic field formed by the magnetic lens, and a magnetic force acts on the filament due to the magnetic field. This can cause the emitter 1 to shift in position, compromising the positional stability of the electron source tip.

[0037] In particular, since magnetic repulsion tends to act in the XY plane direction, when the first side surfaces 50a, 50b of the first filament 50 are in contact with the upper surfaces of the two upper positive terminals 20a, 20b and the contact area is small, or when the second side surfaces 60a, 60b of the second filament 60 are in contact with the upper surfaces of the two upper negative terminals 20c, 20d and the contact area is small, the positional stability of the electron source tip may be further impaired.

[0038] In contrast, in this embodiment, the first sides 50a, 50b of the first filament 50 are connected to the sides 20a', 20b' of the upper positive terminals 20a, 20b, respectively, and the second sides 60a, 60b of the second filament 60 are connected to the sides 20c', 20d' of the upper negative terminals 20c, 20d, respectively.

[0039] The method for connecting the side of the filament and the side of the terminal is not particularly limited, but spot welding, for example, can be used.

[0040] FIG. 2 shows a plan view of the insulator 40 viewed from the electron source chip 10 side in the Z-direction. In FIG. 2, the flow of current indicated by arrow C and the direction of force F generated at that time are shown. As shown in FIG. 2, the first side surfaces 50a, 50b of the first filament 50 are connected to the side surfaces 20a', 20b' of the upper positive terminals 20a, 20b, respectively, and the second side surfaces 60a, 60b of the second filament 60 are connected to the side surfaces 20c', 20d' of the upper negative terminals 20c, 20d, respectively. As a result, it can be seen that the magnetic forces in the XY plane direction that the filament receives are antagonistic in the magnetic field formed by the magnetic lens. As shown on the left and right of FIG. 2, this antagonistic relationship is also established when the current flows in the opposite direction.

[0041] In addition, by joining the ends of the filaments to the side surfaces in this manner, the contact areas between the first side surfaces 50a, 50b and the upper positive terminals 20a, 20b and the contact areas between the second side surfaces 60a, 60b and the upper negative terminals 20c, 20d are increased, which makes the connection between the first filament 50 and the upper positive terminals 20a, 20b and the connection between the second filament 60 and the upper negative terminals 20c, 20d stronger, and also makes it possible to suppress positional changes during long-term use.

[0042] Furthermore, by connecting the first side surfaces 50a, 50b to the side surfaces 20a', 20b' and connecting the second side surfaces 60a, 60b to the side surfaces 20c', 20d', even if the filaments are subjected to a magnetic force in the XY plane direction in the magnetic field formed by the magnetic lens, the upper terminal 20 can support the first filament 50 and the second filament 60 by opposing the force. For example, as shown on the right side of Fig. 2, in the upper positive terminal 20a, a force F due to the first filament 50 is applied to the side surface 20a', and the upper positive terminal 20a supports the first filament 50.

[0043] This improves the positional stability of the electron source tip, and as a result, improves the accuracy of the electron beam irradiation position when used in various devices such as electron beam lithography devices, electron beam drawing devices, multi-electron beam systems, scanning electron microscopes (SEMs), transmission electron microscopes (TEMs), electron beam microanalyzers, and microfocus X-ray devices.

[0044] The insulator 40 of the present embodiment is not particularly limited, but may be made of alumina, for example. The upper terminal 20 and the lower terminal 30 may be bonded to the insulator 40 by, for example, brazing, but is not particularly limited.

[0045] Hereinafter, the emitter 1 of this embodiment will be further described with reference to Fig. 3 to Fig. 4. Fig. 3 to Fig. 4 show top views of the insulator 40, viewed from the electron source tip 10 side, on a first surface perpendicular to the tip direction of the electron source tip 10. The first surface is synonymous with the "XY surface."

[0046] In a plan view of the first surface, the projection lines of the first filament 50 and the second filament 60 onto the first surface are preferably arranged to intersect. As shown in Fig. 3A, the angle θ1 between the projection lines of the first filament 50 and the second filament 60 may be 80° or more and 90° or less, 82° or more and 90° or less, or 84° or more and 90° or less. Also, as shown in Fig. 3B, the angle θ1 between the projection lines of the first filament 50 and the second filament 60 on the first surface may be preferably less than 80°, 10° or more and 75° or less, 20° or more and 70° or less, or 30° or more and 65° or less.

[0047] In this embodiment, the term "planar view" refers to viewing the first surface from a surface along the first surface. In the planar view of the first surface, the first filament 50 and the second filament 60 are projected onto the first surface.

[0048] As shown in FIG. 3A, in a plan view of the first surface, the two upper positive terminals 20a, 20b and the two upper negative terminals 20c, 20d may be arranged such that a line segment l1 connecting the centers of the two upper positive terminals 20a, 20b intersects with a line segment l2 connecting the centers of the two upper negative terminals 20c, 20d.

[0049] The angle θ2 between the line segments l1 and l2 is preferably 80° or more and 90° or less, or may be 82° or more and 90° or less, or 84° or more and 90° or less. Moreover, the angle θ2 is preferably less than 80°, or may be 10° or more and 75° or less, or 20° or more and 70° or less, or 30° or more and 65° or less.

[0050] 3A and 3B, in a plan view of the first surface, the first filament 50 may be disposed such that a line segment connecting the side surfaces 20a', 20b' of the two upper positive terminals 20a, 20b to which the first side surfaces 50a, 50b of the first filament 50 are connected intersects with a line segment l1 connecting the centers of the two upper positive terminals 20a, 20b. Note that the line segment connecting the side surfaces 20a', 20b' is equal to the length of the first filament 50.

[0051] 3A and 3B, in a plan view of the first surface, the second filament 60 may be disposed such that a line segment connecting the side surfaces 20c', 20d' of the two upper negative terminals 20c, 20d to which the second side surfaces 60a, 60b of the second filament 60 are connected intersects with a line segment l2 connecting the centers of the two upper negative terminals 20c, 20d. Note that the line segment connecting the side surfaces 20c', 20d' is equal to the second filament 60.

[0052] In a plan view of the first surface, the first filament 50 may be disposed such that a line segment connecting the side surfaces 20a', 20b' of the two upper positive terminals 20a, 20b to which the first side surfaces 50a, 50b of the first filament 50 are connected does not intersect with a line segment l1 connecting the centers of the two upper positive terminals. Note that the line segment connecting the side surfaces 20a', 20b' is equal to the first filament 50.

[0053] As shown in Fig. 4, in a plan view of the first surface, the second filament 60 may be disposed such that a line segment connecting the side surfaces 20c', 20d' of the two upper negative terminals 20c, 20d to which the second side surfaces 60a, 60b of the second filament 60 are connected does not intersect with a line segment l2 connecting the centers of the two upper negative terminals. Note that here, the line segment connecting the side surfaces 20c', 20d' is equal to the second filament 60. Note that the first filament 50 and the like are omitted in Fig. 4.

[0054] As shown in Fig. 3B, in a plan view of the first surface, the first filament 50 and the second filament 60 may be arranged such that at least the side surfaces 20a', 20b' of the upper positive terminals 20a, 20b to which the first side surfaces 50a, 50b of the first filament 50 are connected face to the side surfaces 20c', 20d' of the upper negative terminals 20c, 20d to which the second side surfaces 60a, 60b of the second filament 60 are connected. Here, "at least face to face" means that, for example, the side surfaces 20a' and 20c' face each other as shown in Fig. 3B, and it is not necessary that the side surfaces 20a' and 20d' face each other.

[0055] As shown in FIG. 3A, in a planar view of the first surface, the first filament 50 and the second filament 60 may be arranged so as not to face the side surfaces 20a', 20b' of the upper positive terminals 20a, 20b to which the first side surfaces 50a, 50b of the first filament 50 are connected, and the side surfaces 20c', 20d' of the upper negative terminals 20c, 20d to which the second side surfaces 60a, 60b of the second filament 60 are connected. [Industrial Applicability]

[0056] The present invention has industrial applicability as an emitter. [Explanation of symbols]

[0057] 1 Emitter, 10...electron source tip, 10a...first position, 10b...second position, 11...diffusion source, 20...upper terminal, 20a...upper positive terminal, 20a'...side, 20b...upper positive terminal, 20b'...side, 20c...upper negative terminal, 20c'...side, 20d...upper negative terminal, 20d'...side, 30...lower terminal, 30a...lower positive terminal, 30b...lower negative terminal, 40...insulator, 40a...surface, 40b...surface, 50...first filament, 50a...first side, 50b...first side, 60...second filament, 60a...second side, 60b...second side, 80a...upper and lower positive terminal connection portion, 80b...upper and lower negative terminal connection portion, 81a...upper positive terminal connection portion, 81b...upper negative terminal connection portion

Claims

1. An electron source chip; a first filament connected to a first location on a side of the electron source tip; a second filament connected to a second location on a side of the electron source tip; two upper positive terminals to which the two first side surfaces of the first filament are respectively connected; two upper negative terminals to which the two second side surfaces of the second filament are respectively connected; one lower positive terminal electrically connected to the two upper positive terminals; a lower negative terminal electrically connected to the two upper negative terminals; an insulator carrying the upper positive terminal, the upper negative terminal, the lower positive terminal, and the lower negative terminal; the first position and the second position are different positions, the first side of the first filament is connected to a side of the upper positive terminal, the second side of the second filament is connected to a side of the upper negative terminal, Emitter.

2. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the two upper positive terminals and the two upper negative terminals are arranged such that a line segment connecting the centers of the two upper positive terminals intersects with a line segment connecting the centers of the two upper negative terminals; The emitter of claim 1 .

3. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, The projection lines of the first filament and the second filament on the first surface are arranged to intersect. The emitter of claim 1 .

4. In a plan view of the first surface, The angle θ1 between the projection lines of the first filament and the second filament is 80° or more and 90° or less. The emitter of claim 3.

5. In a plan view of the first surface, The angle θ1 between the projection lines of the first filament and the second filament is less than 80°. The emitter of claim 3.

6. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament is disposed such that a line segment connecting the side surfaces of the two upper positive terminals to which the first side surface of the first filament is connected intersects with a line segment connecting the centers of the two upper positive terminals; The emitter of claim 1 .

7. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the second filament is disposed such that a line segment connecting the side surfaces of the two upper negative terminals to which the second side surface of the second filament is connected intersects with a line segment connecting the centers of the two upper negative terminals. The emitter of claim 1 .

8. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament is disposed such that a line segment connecting the side surfaces of the two upper positive terminals to which the first side surface of the first filament is connected does not intersect with a line segment connecting the centers of the two upper positive terminals. The emitter of claim 1 .

9. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the second filament is disposed such that a line segment connecting the side surfaces of the two upper negative terminals to which the second side surface of the second filament is connected does not intersect with a line segment connecting the centers of the two upper negative terminals. The emitter of claim 1 .

10. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament and the second filament are arranged such that the side surface of the upper positive terminal to which the first side surface of the first filament is connected faces at least the side surface of the upper negative terminal to which the second side surface of the second filament is connected. The emitter of claim 1 .

11. In a plan view of a first surface perpendicular to a front end direction of the electron source tip, the first filament and the second filament are arranged such that the side of the upper positive terminal to which the first side surface of the first filament is connected does not face the side of the upper negative terminal to which the second side surface of the second filament is connected. The emitter of claim 1 .

12. the first filament is joined at a position closer to the tip of the electron source tip than the second filament; The emitter of claim 1 .

13. the second filament is joined at a position closer to the tip of the electron source tip than the first filament; The emitter of claim 1 .

14. The pair of upper positive terminals each have a positive terminal connection portion that electrically connects the pair of upper positive terminals, The pair of upper negative terminals have negative terminal connection portions that electrically connect the pair of upper negative terminals. The emitter of claim 1 .

Images