Focused Ion Beam Equipment

Abstract

To provide a focused ion beam device capable of quickly and accurately adjusting a current value of an ion beam.SOLUTION: A focused ion beam device comprises: a condenser lens for processing an ion beam so that the ion beam has a parallel beam shape; an electrically-driven aperture between the condenser lens and an object lens, the electrically-driven aperture changing the passing area of the ion beam processed by the condenser lens to control its beam diameter; and a plurality of beam shield plate units each of which is composed of a pair of beam shield plates that face each other so as to hold the ion beam after passing through the condenser lens from both sides and are movable along a direction perpendicular to the ion beam's optical axis, the plurality of beam shield plate units surrounding the ion beam to set a passing ion beam diameter of the ion beam, the plurality of beam shield plate units being offset from each other along the ion beam's optical axis direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a focused ion beam device. [Background technology]

[0002] Conventional focused ion beam devices are configured to focus an ion beam on a sample surface using a two-stage electrostatic lens system consisting of a condenser lens and an objective lens. An ion beam is generated when a liquid metal, for example, gallium, is ionized by field emission. After being emitted from the tip of a liquid metal ion source, this ion beam is accelerated by an acceleration voltage (partially an ion overvoltage) and enters the condenser lens while spreading in a cone shape at a predetermined radiation angle. The trajectory of the ion beam that enters the condenser lens is changed by the electric field distribution inside the condenser lens, so that the spread of the beam is alleviated and the beam is processed into a radiation shape with a spread narrower than the above-mentioned predetermined radiation angle.

[0003] Known conventional focused ion beam devices include a technology in which apertures are arranged on the upstream and downstream sides of a condenser lens (see, for example, Patent Document 1). The aperture arranged on the downstream side of the condenser lens is capable of setting a plurality of holes with different diameter dimensions. This downstream aperture can adjust the aperture area through which the ion beam having the above-mentioned diverging radial shape passes. In this focused ion beam device, the ion beam that passes through the downstream aperture is focused by the objective lens and reaches the sample surface. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-64788 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned focused ion beam device, the ion beam that has passed through the condenser lens reaches the downstream aperture with the radial shape intact. In the radial ion beam, there is a bias in the amount of passing ions at a position perpendicular to the optical axis. Therefore, every time the diameter of the hole in the downstream aperture changes, the characteristics of the ion beam that has passed through this aperture change. Therefore, in the above-mentioned focused ion beam device, it is necessary to individually adjust the astigmatism correction voltage and the axial adjustment aligner voltage every time the aperture of the downstream aperture is switched to a different diameter. This causes a problem that it takes time to adjust the current value of the ion beam.

[0006] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a focused ion beam apparatus capable of adjusting the current value of an ion beam quickly and accurately. [Means for solving the problem]

[0007] In order to solve the above problems and achieve the object, an aspect of the present invention is a liquid metal ion source, a condenser lens that processes an ion beam generated from the liquid metal ion source, and an object lens that focuses the ion beam that has passed through the condenser lens and irradiates it on a sample surface. 、 The condenser lens processes the ion beam into a parallel beam shape, and an electric aperture is provided between the condenser lens and the object lens to change the passing area of ​​the ion beam processed by the condenser lens to control the beam diameter. a secondary charged particle detector for detecting intensity information of secondary charged particles generated from a position on the sample surface where the ion beam is irradiated, and a deposition gas supply pipe for supplying a deposition gas toward the sample surface, the motorized aperture includes a plurality of beam shielding plate units each including a pair of beam shielding plates that face each other so as to sandwich the ion beam that has passed through the condenser lens from both sides and that are movable along a direction perpendicular to the optical axis of the ion beam, the beam shielding plates constituting the plurality of beam shielding plate units surround the ion beam to set a passing area of ​​the ion beam, The motorized aperture is set so that the beam diameter of the ion beam changes between an ion beam passing area that provides a beam current value suitable for observing the sample surface and an ion beam passing area that provides a beam current value suitable for processing the sample surface. It is characterized by:

[0008] In the above aspect, it is preferable that an astigmatism correcting stigma having a plurality of pole lenses arranged to surround the ion beam is arranged downstream of the motorized aperture, and the motorized aperture has the same number of beam shielding plates as the pole lenses.

[0009] In the above aspect, it is preferable that the motorized aperture is composed of four beam shielding plate units, and the beam shielding plate units are arranged at positions rotated by an angle of 45 degrees from each other along the outer circumferential direction of the ion beam, centered on the optical axis of the ion beam, when projected from the optical axis direction of the ion beam.

[0010] In the above aspect, it is preferable that the beam shielding plate units move synchronously with each other so that the beam shielding plates are spaced the same distance from each other relative to the optical axis of the ion beam.

[0011] In the above aspect, it is preferable that the plurality of beam shielding plate units move in a synchronized manner.

[0012] In the above aspect, it is preferable that the motorized aperture continuously changes the passing area of ​​the ion beam.

[0013] In the above aspect, it is preferable that, when projected from the optical axis direction of the ion beam, the plurality of beam shielding plate units have an opening for passing the ion beam, which is a polygon whose periphery changes regularly along the electric field control direction by the astigmatism correcting stigma, with the optical axis of the ion beam as its center.

[0014] In the above aspect, it is preferable that, when projected in the optical axis direction of the ion beam, the plurality of beam blocking plates constituting the motorized aperture are arranged at positions corresponding sequentially to the pole lenses.

[0015] In the above aspect, it is preferable to include a selective aperture substrate in which a plurality of apertures having different aperture diameters are formed, for controlling the beam diameter of the ion beam. Effect of the Invention

[0016] According to the focused ion beam device of the present invention, the current value of the ion beam can be adjusted quickly and accurately. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram illustrating a configuration of a focused ion beam apparatus according to a first embodiment of the present invention. [Figure 2-1] FIG. 2-1 is an explanatory diagram showing a projection of an ion beam in the optical axis direction in a focused ion beam device according to a first embodiment of the present invention, and shows a state in which the ion beam passing area (opening) of the electric aperture is set wide. [Figure 2-2] FIG. 2-2 is an explanatory diagram showing a projection of an ion beam in the optical axis direction in the focused ion beam device according to the first embodiment of the present invention, and shows a state in which the ion beam passing area (opening) of the electric aperture is set narrow. [Diagram 3] FIG. 3 is an explanatory diagram showing the operation of the beam shielding plate unit in the focused ion beam apparatus according to the first embodiment of the present invention. [Figure 4] FIG. 4 is a plan view of a stigma for correcting astigmatism in the focused ion beam apparatus according to the first embodiment of the present invention. [Diagram 5] FIG. 5 is a diagram showing the relationship between the beam current and the beam diameter when an ion beam is generated using the focused ion beam device according to the present invention. [Figure 6] FIG. 6 is a schematic diagram illustrating a configuration of a focused ion beam apparatus according to a second embodiment of the present invention. [Figure 7] FIG. 7 is a plan view showing a selective aperture substrate in a focused ion beam apparatus according to the second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The following describes the details of a focused ion beam device according to an embodiment of the present invention with reference to the drawings. However, it should be noted that the drawings are schematic, and the number of each member, the size of each member, the dimensional ratio, the shape, etc., differ from the actual ones. In addition, there are parts in which the dimensional relationships, ratios, and shapes differ between the drawings.

[0019] The focused ion beam device according to the present embodiment can be used to repair samples such as photomasks, TFT substrates, etc. The focused ion beam device of the present invention can also be applied to a drawing device that performs direct drawing on a sample, a scanning electron microscope that enables observation of the surface state of a sample, etc.

[0020] [First embodiment] (Schematic configuration of focused ion beam device)

[0021] FIG. 1 shows a schematic configuration of a focused ion beam apparatus 1 according to a first embodiment. The focused ion beam apparatus 1 includes a focused ion beam column (hereinafter, referred to as a FIB column). The FIB column 2 includes a substrate support 15 on which a sample S is placed, and an XY stage for moving the substrate support 15 in the XY directions and an elevator for moving the substrate support 15 in the Z direction.

[0022] A vacuum pump (not shown) is connected to the FIB column 2, so that the inside of the FIB column 2 is kept at a predetermined low pressure. Inside the FIB column 2, a liquid metal ion source 3, a condenser lens 4, an electric aperture 5, a stigma 6 for astigmatism correction, a blanker 7, a blanking aperture 8, a deflector 9, an object lens 10, a secondary charged particle detector 11, and a deposition gas supply pipe 12 are arranged in this order.

[0023] The liquid metal ion source 3 includes a liquid metal, for example, gallium (Ga). In the liquid metal ion source 3, the liquid metal is ionized by field emission and emitted from the tip of the liquid metal ion source 3. The gallium ions (Ga + ) is accelerated by an acceleration voltage (part of which is an ion overvoltage) by the upstream-most extraction electrode in the condenser lens 4, becoming an ion beam IB having a predetermined emission angle.

[0024] The condenser lens 4 is an electrostatic lens, and is set so as to convert the incident ion beam IB into a parallel beam shaped ion beam IBP.

[0025] As shown in Fig. 1 and Fig. 2-1, the motorized aperture 5 includes four beam shielding plate units 51, 52, 53, and 54. These beam shielding plate units 51, 52, 53, and 54 are arranged at positions offset from one another along the optical axis direction of the ion beam IBP. Note that the directions A1, A2, A3, and A4 shown in Fig. 1 are drawn in the same direction in the drawing, but in reality, as shown in Fig. 2-1, they are set to be oriented in directions rotated by 45 degrees from one another around the optical axis IBa.

[0026] FIG. 3 shows a projection of the beam shielding plate unit 51 seen from the direction of the optical axis IBa of the ion beam IBP. As shown in FIG. 2-1 and FIG. 3, the beam shielding plate unit 51 is made up of a pair of beam shielding plates 5A and 5E. As shown in FIG. 2-1, the beam shielding plate unit 52 is made up of a pair of beam shielding plates 5B and 5F. The beam shielding plate unit 53 is made up of a pair of beam shielding plates 5C and 5G. The beam shielding plate unit 54 is made up of a pair of beam shielding plates 5D and 5H. Note that in FIG. 2-1 and FIG. 2-2, although there are overlapping portions in the projection, all the beam shielding plates 5A to 5H are drawn with solid lines for convenience of explanation.

[0027] The beam shielding plates 5A and 5E of the beam shielding plate unit 51 are arranged facing each other so as to sandwich the ion beam IBP, which has passed through the condenser lens 4 and become a parallel beam shape, from both sides (both sides in the direction A1 perpendicular to the optical axis IBa). These beam shielding plates 5A and 5E are set to move synchronously so as to approach and move away from each other along the direction A1. The beam shielding plates 5A and 5E are driven by an actuator (not shown) so as to move along the direction A1.

[0028] This beam shielding plate unit 51 can change the passing width of the ion beam IBP evenly from both sides by moving the beam shielding plates 5A and 5E closer to each other or farther away from each other. Also, by moving the beam shielding plates 5A and 5E farther away from each other, it is possible to move them back to a position where they do not interfere with the ion beam IBP.

[0029] The beam shielding plate units 52, 53, and 54 have the same configuration as the beam shielding plate unit 51. However, the beam shielding plate unit 52 is arranged such that the beam shielding plates 5B and 5F move along a direction A2 as shown in Fig. 2-1. The direction A2 is a direction obtained by rotating the beam shielding plates 5B and 5F clockwise by 45 degrees in the drawing with the optical axis IBa of the ion beam IBP as the center of rotation with respect to the above-mentioned direction A1.

[0030] 2-1, the beam shielding plate unit 53 is arranged so that the beam shielding plates 5C and 5G move along a direction A3. The direction A3 is a direction rotated by 45 degrees clockwise around the optical axis IBa of the ion beam IBP as a rotation center with respect to the direction A2.

[0031] 2-1, the beam shielding plate unit 54 is arranged so that the beam shielding plates 5D and 5H move along a direction A4. The direction A4 is a direction rotated by 45 degrees clockwise around the optical axis IBa of the ion beam IBP as a rotation center with respect to the direction A3.

[0032] The motorized aperture 5 having the above configuration can control the diameter of the aperture AP to be formed to change continuously by controlling the movement of the eight beam shielding plates 5A-5H constituting the four beam shielding plate units 51, 52, 53, 54. The aperture AP is a polygon whose periphery changes regularly along the electric field control direction by the astigmatism correcting stigma 6, centered on the optical axis IBa of the ion beam IBp. According to this embodiment, even if the aperture AP is not circular, the passing area of ​​the ion beam IBp can be adjusted continuously with high precision.

[0033] The ion beam IBp passes through the motorized aperture 5 and has its beam diameter adjusted to become an ion beam IBt. FIG. 2-1 shows an aperture AP1 in a state where the diameter of the aperture AP of the motorized aperture 5 is controlled to be large. In this embodiment, the case where the diameter of the aperture AP is larger than the diameter of the ion beam IBp is also included. FIG. 2-2 shows an aperture AP2 in a state where the diameter of the aperture AP of the motorized aperture 5 is controlled to be small. In this state, the ion beam IBp is processed by the motorized aperture 5 so that the beam diameter becomes small.

[0034] As shown in FIG. 4, in this embodiment, the stigma 6 for correcting astigmatism is composed of eight pole lenses (octupole lenses) 6A, 6B, 6C, 6D, 6E, 6F, 6G, and 6H, which are a combination of two sets of quadrupole lenses. The two sets of quadrupole lenses are arranged by rotating 45 degrees around the optical axis IBa of the ion beam IBt, and the pole lenses 6A to 6H are arranged at positions rotated 45 degrees from each other. By changing the magnitude and ratio of the current values ​​of the two sets of quadrupole lenses, the correction amount and correction direction of the ion beam IBt can be changed. The eight beam shielding plates 5A to 5H constituting the motorized aperture 5 described above are arranged at positions corresponding to the pole lenses 6A to 6H.

[0035] The blanker 7 has a function of deflecting the ion beam IBt by applying a blanking voltage thereto, and guiding the ion beam IBt to a light-shielding portion (a region where no opening is formed) of a blanking aperture 8 so that the ion beam IBt is not directed toward the sample S.

[0036] The deflector 9 can deflect the ion beam IBt that has passed through the motorized aperture 5 to scan it in the X and Y directions. The object lens 10 focuses the ion beam IBt so as to be focused on the upper surface of the sample S according to control.

[0037] As shown in FIG. 1, a secondary charged particle detector 11 and a deposition gas supply pipe 12 are provided at the bottom of the FIB column 2 .

[0038] The control unit 13 is connected to the liquid metal ion source 3, the condenser lens 4, the motorized aperture 5, the stigma for astigmatism correction 6, the blanker 7, the deflector 9, the secondary charged particle detector 11, and a deposition gas supply unit (not shown) that supplies deposition gas to the deposition gas supply pipe 12.

[0039] (Action, Operation and Effects) In the focused ion beam device 1 configured as above, an extraction voltage is applied to the liquid metal ion source 3 based on a control signal from the control unit 13, whereby an ion beam IB is emitted from the liquid metal ion source 3 in a predetermined radial shape.

[0040] Based on a control signal from the control unit 13, the condenser lens 4 processes the ion beam IB emitted from the liquid metal ion source 3 into a parallel beam shaped ion beam IBp.

[0041] In the motorized aperture 5, the beam shielding plate units 51, 52, 53, and 54 are operated based on a control signal from the control unit 13, and the diameter dimension of the aperture AP that determines the passing area of ​​the ion beam IBp is set. The motorized aperture 5 can control the desired beam current value and beam diameter that reach the upper surface of the sample S by setting the diameter dimension of the aperture AP.

[0042] Figures 2-1 and 2-2 show the state where the width of the opening AP of the motorized aperture 5 is changed. Figure 2-1 shows the state where it is set to opening AP1, which has a relatively wide passing area that can ensure a beam current value and beam diameter of strength suitable for processing the sample S. Figure 2-2 shows the state where it is set to opening AP2, which has a relatively narrow passing area that realizes a beam current value and beam diameter of strength suitable for detecting the portion of the sample S to be processed and observing the surface.

[0043] An ion beam IBt (see FIG. 1) that passes through an electric aperture 5 set to a relatively wide opening AP1 as shown in FIG. 2-1 is focused by an object lens 10 and set to be irradiated onto a planned processing location of a sample S. At this time, a deposition gas is supplied from a deposition gas supply pipe 12 toward the sample S, so that a deposition film can be formed on the upper surface of the sample S.

[0044] An ion beam IBt (see FIG. 1) having a small beam diameter that passes through an electric aperture 5 set to a relatively narrow opening AP2 as shown in FIG. 2-2 is set to be focused by an object lens 10 and irradiated onto a location of the sample S to be observed. At this time, a secondary charged particle detector 11 captures secondary charged particles (secondary electrons, secondary ions, etc.) generated from the position irradiated with the ion beam IBt. Based on the intensity information detected by this secondary charged particle detector 11, data can be acquired as an image while scanning the ion beam IBt. This makes it possible to confirm the surface shape of the sample S irradiated with the ion beam IBt. The scanning operation of the ion beam IBt is performed by the action of a deflector 9.

[0045] 5 shows the relationship between the current value of the ion beam IBt reaching the surface of the sample S and the beam diameter when the focused ion beam device 1 according to the present embodiment is used. Curves (1), (2), and (3) are examples in which the voltages applied to the parallel beam ion beam IBp are 15 kV, 10 kV, and 5 kV, respectively, and show the relationship that the beam diameter decreases as the beam current value decreases, and the beam diameter increases as the beam current value increases.

[0046] Position Co, indicated by a circle on curve (1), is the position where the beam current and beam diameter suitable for observing the surface of sample S can be obtained. Specifically, at position Co, the beam current is 1 pA and the beam diameter is 40 nm. Since the beam current at position Co is small, the sample S will not be damaged.

[0047] Moreover, position Cp indicated by a circle on curve (1) is a position where a beam current value and beam diameter suitable for processing the surface of sample S can be obtained. Specifically, at position Cp, a beam current value of 20 nA and a beam diameter of 2.5 μm can be realized. The movement between the above-mentioned conditions of position Co and position Cp can be changed continuously and quickly by controlling the opening of motorized aperture 5.

[0048] In particular, according to the focused ion beam device 1 of this embodiment, the ion beam IBP having a parallel beam shape is formed by the condenser lens 4, so that there is little bias in the beam intensity (transmitted ion density) in a direction perpendicular to the optical axis of the ion beam IBP. Furthermore, since the ion beam IBP having a parallel beam shape is formed by the condenser lens 4, even if the beam shielding plate units 51, 52, 53, and 54 are offset along the optical axis IBa, the beam is uniformly shielded near the outer periphery of the ion beam IBP, so that it is possible to avoid deterioration of the focusing performance of the ion beam IBt.

[0049] In the focused ion beam device 1 according to the present embodiment, the number of beam shielding plates 5A-5H constituting the motorized aperture 5 is the same as the number of pole lenses 6A-6H constituting the astigmatism correcting stigma 6, and the positions of the beam shielding plates 5A-5H and the pole lenses 6A-6H are matched. Therefore, even if the diameter dimension of the opening AP of the motorized aperture 5 is continuously changed, the beam current value can be adjusted without changing the correction action of the electric field from the astigmatism correcting stigma 6 that the ion beam IBt receives. Therefore, even if the diameter dimension of the opening AP of the motorized aperture 5 is changed, it is not necessary to adjust the astigmatism correction or the axial adjustment aligner correction each time. Therefore, according to the focused ion beam device 1 according to the present embodiment, the beam current value can be continuously and quickly adjusted.

[0050] As described above, in this embodiment, the electric aperture 5 can continuously adjust the beam current value, so that the astigmatism correction voltage, the aligner voltage, and the focus voltage (the voltage of the condenser lens 4 and the object lens 10) can be adjusted in a state where the beam current value is set low, for example, to 1 pA, as in the condition of the position Co shown in FIG. 5. At this time, since the beam current value is low, sputtering hardly occurs on the surface of the sample S, and the sample S can be accurately adjusted without being damaged. Even if the diameter of the opening AP is greatly changed by the electric aperture 5 in this state, only the beam current value can be increased without changing the focus condition. That is, according to this embodiment, it is possible to change to the condition of the position Cp shown in FIG. 5 (beam current value is 20 nA) and immediately process the sample S.

[0051] In the focused ion beam device 1 according to this embodiment, if the beam shielding plates 5A-5H of the motorized aperture 5 are configured to move in eight directions (A1, A2, A3, A4) in accordance with electrodes such as an aligner and a deflector 9 (not shown) in addition to the astigmatism correcting stigma 6 to limit the beam current value, it becomes possible to adjust the beam current value without being affected by the astigmatism correction.

[0052] In the focused ion beam device 1 according to the present embodiment, the condenser lens 4 converts the ion beam IB into a parallel beam shaped ion beam IBP, so that even if the beam shielding plate units 51, 52, 53, and 54 are offset in the optical axis IBa direction, the beam diameter of the ion beam IBP can be uniformly narrowed down from the outer periphery side.

[0053] Generally, when observing the surface of sample S, even if an attempt is made to narrow the beam diameter by controlling ion beam IBp with astigmatism correcting stigma 6, the adjustment takes time, which causes damage to sample S. In this embodiment, since it is only necessary to move motorized aperture 5 without changing the conditions of astigmatism correcting stigma 6, no adjustment is required and observation can be performed quickly without taking much time.

[0054] [Second embodiment] 6 shows a schematic configuration of a focused ion beam apparatus 1A according to a second embodiment of the present invention. The configuration of this focused ion beam apparatus 1A is substantially similar to the configuration of the focused ion beam apparatus 1 according to the above-mentioned first embodiment, and differs in that the focused ion beam apparatus 1A is configured to include a selective aperture substrate 14.

[0055] As shown in Fig. 6, the selective aperture substrate 14 is disposed downstream of the motorized aperture 5. As shown in Fig. 7, the selective aperture substrate 14 has openings 14A, 14B, 14C, and 14D with gradually differing aperture diameters arranged in a row along the longitudinal direction of a metal plate having beam shielding properties. In this embodiment, the selective aperture substrate 14 is set so that the row direction coincides with the direction A1.

[0056] In this embodiment, the beam diameter of the ion beam IBp can be adjusted using the selective aperture substrate 14 in addition to the motorized aperture 5. In this embodiment, the selective aperture substrate 14 is used in a beam mode in which the ion beam IB emitted from the liquid metal ion source 3 is focused near the selective aperture substrate 14 by the condenser lens 4. At this time, the diameter of the aperture AP is made large so that there is no influence of the motorized aperture 5. Then, the openings 14A, 14B, 14C, and 14D of the selective aperture substrate 14 are selected, and the selective aperture substrate 14 is moved by an actuator (not shown) to adjust the beam current value.

[0057] In Fig. 5, curve (4) is a continuous graph showing the beam current value and beam diameter when each of the openings 14A, 14B, 14C, and 14D is selected when the selective aperture substrate 14 is used with an applied voltage of 15 kV. In a beam mode in which the ion beam IB is focused near the selective aperture substrate 14, the selective aperture substrate 14 can be used to select a smaller beam diameter by reducing the beam current value for observation. For this reason, when observing the surface of the sample S, it is effective to use the selective aperture substrate 14 to obtain a small beam diameter with a small beam current value.

[0058] (Other embodiments) Although the embodiment of the present invention has been described above, the description and drawings forming a part of the disclosure of the embodiment should not be understood as limiting the present invention. From this disclosure, various alternative embodiments, examples and operating techniques will become apparent to those skilled in the art.

[0059] In each of the above-mentioned embodiments, the number of beam shielding plates 5A-5H constituting the motorized aperture 5 is set to be the same as the number of pole lenses 6A-6H of the astigmatism correcting stigma 6, but as described above, the number of beam shielding plates constituting the motorized aperture 5 may be configured to be the same as the number of electrodes of the aligner and the deflector 9 (not shown). It is preferable that the number of electrodes of the aligner and the number of pole lenses of the astigmatism correcting stigma 6 are the same. Also, in each of the above-mentioned embodiments, the number of beam shielding plates 5A-5H is eight, but this is not limited to this as long as they are configured in multiple pairs.

[0060] In each of the above embodiments, the deposition gas supply pipe 12 is provided at the bottom of the FIB column 2 to supply the deposition gas, but an etching gas may be supplied instead.

[0061] In each of the above embodiments, the ion beam current value can be increased to sputter and process the surface of the sample S. By utilizing this phenomenon, the focused ion beam device 1, 1A can also be used as a repair device for a photomask or the like.

[0062] In each of the above-described embodiments, in the beam shielding plate units 51, 52, 53, and 54, the pair of beam shielding plates constituting each unit are set to move synchronously with each other so as to be at the same distance from each other with respect to the optical axis IBa of the ion beam IBP. However, as long as the movement is completed when processing or observation is performed using the ion beam IBt, the beam shielding plates may be configured not to be synchronized with each other. [Explanation of symbols]

[0063] AP,AP1,AP2 opening IB Ion Beam IBa Ion beam optical axis IBp Parallel ion beam IBt Passed ion beam 1,1A Focused Ion Beam Equipment 2. Focused ion beam column (FIB column) 3. Liquid metal ion source 4 Condenser Lens 5 Motorized Aperture 5A~5H Beam shield plate 6 Stigma for astigmatism correction 6A~6H Polar Lens 7. Blanka 8 Blanking Aperture 9 Deflector 10 Object Lens 11 Secondary charged particle detector 12 Deposition gas supply pipe 13 Control section 14 Selective aperture board 14A,14B,14C,14D opening 15 Substrate support stand 51, 52, 53, 54 Beam shielding plate unit

Claims

1. a liquid metal ion source, a condenser lens for processing an ion beam generated from the liquid metal ion source, and an object lens for focusing the ion beam that has passed through the condenser lens and irradiating the ion beam on a sample surface; The condenser lens processes the ion beam into a parallel beam shape, A focused ion beam apparatus comprising: an electric aperture between the condenser lens and the object lens, the electric aperture controlling a beam diameter by changing a passing area of ​​the ion beam processed by the condenser lens, a secondary charged particle detector for detecting intensity information of secondary charged particles generated from a position on the sample surface where the ion beam is irradiated; a deposition gas supply pipe for supplying a deposition gas toward the sample surface; Equipped with The motorized aperture is a plurality of beam shielding plate units each including a pair of beam shielding plates that face each other so as to sandwich the ion beam that has passed through the condenser lens from both sides and that are movable along a direction perpendicular to the optical axis of the ion beam; the beam shielding plates constituting the plurality of beam shielding plate units surround the ion beam to set a passing area of ​​the ion beam; the motorized aperture is set so as to change a beam diameter of the ion beam between an ion beam passing area that results in a beam current value suitable for observing the sample surface and an ion beam passing area that results in a beam current value suitable for processing the sample surface.

2. an astigmatism correction stigma having a plurality of pole lenses arranged to surround the ion beam downstream of the motorized aperture; The motorized aperture includes the same number of beam blocking plates as the number of the pole lenses.

2. The focused ion beam device according to claim 1.

3. the motorized aperture is composed of four of the beam shielding plate units, the beam shielding plate units are disposed at positions rotated by an angle of 45 degrees from each other along a circumferential direction of the ion beam, with the optical axis of the ion beam as a center, when projected from the optical axis direction of the ion beam; 3. The focused ion beam device according to claim 1 or 2.

4. the beam shielding plate unit moves synchronously with the optical axis of the ion beam such that the beam shielding plates are spaced the same distance from each other. The focused ion beam device according to any one of claims 1 to 3.

5. The plurality of beam shielding plate units move synchronously. The focused ion beam device according to any one of claims 1 to 4.

6. The motorized aperture continuously changes the passing area of ​​the ion beam. The focused ion beam device according to claim 1 .

7. the plurality of beam shielding plate units each have an opening for passing the ion beam, the opening being a polygon whose periphery changes regularly along a direction of electric field control by the astigmatism correcting stigma, with the optical axis of the ion beam as a center, when projected from the optical axis direction of the ion beam; 3. The focused ion beam device according to claim 2.

8. In the projection from the optical axis direction of the ion beam, the plurality of beam shielding plates constituting the motorized aperture are arranged at positions corresponding to the pole lenses in sequence.

3. The focused ion beam device according to claim 2.

9. A selective aperture substrate is provided on which a plurality of apertures having different aperture diameters are formed, the selective aperture substrate controlling the beam diameter of the ion beam. The focused ion beam device according to any one of claims 1 to 8.

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