Charged particle beam device and method for replacing charged particle source unit

Abstract

To provide a charged particle beam device that allows easy replacement of a charged particle source.SOLUTION: A charged particle beam device according to the present invention includes an electron gun chamber 202, a filament unit 600 having a charged particle source, a support member 700 provided on a side wall of the electron gun chamber 202 and detachably supporting the filament unit 600 within the electron gun chamber 202, and a chamber door 204 provided on the side wall of the electron gun chamber 202 for accessing the inside of the electron gun chamber 202.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a charged particle beam device and a method for replacing a charged particle source unit. [Background technology]

[0002] Charged particle beam devices such as transmission electron microscopes, scanning electron microscopes, and focused ion beam devices emit charged particle beams from a charged particle source. Charged particle sources have a limited lifespan and must be replaced periodically. For example, Patent Document 1 discloses a method for replacing a filament that serves as the electron source of an electron microscope. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 52-98462 Summary of the Invention [Problem to be solved by the invention]

[0004] In such a charged particle beam device, it is desirable that the charged particle source can be easily replaced. [Means for solving the problem]

[0005] One aspect of the charged particle beam device according to the present invention is A chamber; a charged particle source unit having a charged particle source; a support member provided on a side wall of the chamber and configured to detachably support the charged particle source unit within the chamber; a chamber door provided on a side wall of the chamber for accessing the inside of the chamber; Includes.

[0006] In such a charged particle beam device, the charged particle source unit can be removed or installed through a chamber door provided on the side wall of the chamber, making it easy to replace the charged particle source unit.

[0007] One aspect of the method for replacing a charged particle source unit according to the present invention includes: A chamber; a charged particle source unit having a charged particle source; a support member provided on a side wall of the chamber and configured to detachably support the charged particle source unit within the chamber; a chamber door provided on a side wall of the chamber for accessing the inside of the chamber, the method comprising: opening the chamber door; removing a first charged particle source unit from the support member; introducing a second charged particle source unit into the chamber through the chamber door and attaching the second charged particle source unit to the support member; Includes:

[0008] In such a method for replacing a charged particle source unit, the first charged particle source unit is removed from a chamber door provided on a side wall of the chamber, and the second charged particle source unit is introduced. This allows for easy replacement of the charged particle source unit. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a transmission electron microscope. [Figure 2] FIG. [Figure 3] FIG. 1 is a front view schematically showing a transmission electron microscope. [Figure 4] FIG. 2 is a diagram schematically illustrating a state in which the housing door of the housing is open. [Figure 5] FIG. 2 is a perspective view schematically showing an electron gun chamber. [Figure 6]FIG. 2 is a perspective view schematically showing an electron gun chamber. [Figure 7] FIG. 2 is a perspective view schematically showing an electron gun chamber. [Figure 8] FIG. 2 is a perspective view schematically showing the bottom of the electron gun chamber. [Figure 9] FIG. 2 is a cross-sectional perspective view schematically showing a filament unit. [Figure 10] FIG. 2 is an exploded perspective view schematically showing a filament unit. [Figure 11] FIG. 10 is a perspective view schematically showing a state in which a filament unit is attached to an attachment portion of a support portion. [Figure 12] FIG. 10 is a perspective view schematically showing a state in which the filament unit is attached to the attachment portion of the support portion. [Figure 13] FIG. 10 is a perspective view schematically showing a state in which the filament unit is attached to the attachment portion of the support member. [Figure 14] 5A and 5B are diagrams illustrating a locking mechanism for fixing the filament unit to the support member. [Figure 15] 10 is a flowchart showing an example of a method for replacing a filament unit. [Figure 16] FIG. [Figure 17] FIG. [Figure 18] FIG. 10 is a perspective view schematically showing a step of removing the first filament unit. [Figure 19] FIG. 10 is a perspective view schematically showing a step of attaching a second filament unit. [Figure 20] 10 is a flowchart showing an example of a voltage boosting process performed by a control unit. [Figure 21] 10 is a flowchart showing an example of a start process of a control unit. [Figure 22] FIG. 2 is a diagram for explaining a power supply circuit for applying an acceleration voltage. [Figure 23] FIG. 10 is a diagram for explaining a power supply circuit when a discharge occurs. [Figure 24] 10 is a flowchart showing an example of an automatic voltage increase process in the start function of the control unit. [Figure 25]FIG. 4 is a diagram showing an example of an acceleration voltage step-up / step-down operation. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the embodiments described below do not unduly limit the content of the present invention as defined in the claims. Furthermore, not all of the configurations described below are necessarily essential components of the present invention.

[0011] In addition, the following describes a case where the charged particle beam device of the present invention is a transmission electron microscope that has a filament as a charged particle source and generates an electron beam from the filament, but the charged particle beam device of the present invention may also be a device in which the charged particle source generates a charged particle beam other than an electron beam (such as an ion beam).

[0012] 1. Transmission Electron Microscopy 1.1. Configuration of a transmission electron microscope First, a transmission electron microscope according to one embodiment of the present invention will be described with reference to the drawings. Figure 1 is a diagram showing an example of the configuration of a transmission electron microscope 2 according to one embodiment of the present invention.

[0013] As shown in FIG. 1, the transmission electron microscope 2 includes a housing 100, a main body 200, and a sample holder. The system includes a control unit 400, a vacuum pumping system 500, and a vacuum pumping system 500.

[0014] The housing 100 houses a main body 200, a control unit 400, and a vacuum pumping system 500. The housing 100 may house only the main body 200. The housing 100 is provided with a housing door 104 for accessing the electron gun chamber 202.

[0015] The main body 200 includes an electron source 210, an irradiation optical system 220 for irradiating the sample S with electrons emitted from the electron source 210, a holder support part 230 having an insertion port through which the sample holder 300 can be inserted and removed, an imaging optical system 240 for imaging the electrons that have passed through the sample S, an imaging device 250 for capturing a transmission electron microscope image (TEM image) formed by the electrons that have passed through the sample S, and a detector 260 for detecting the electrons that have passed through the sample S to obtain a scanning transmission electron microscope image (STEM image).

[0016] The electron source 210 is housed in the electron gun chamber 202. The electron source 210 is, for example, a tungsten filament, and constitutes an electron gun that emits an electron beam. The filament unit 600 is a unit that includes a filament and a Wehnelt. The electron source 210 can be replaced by replacing the filament unit. The filament unit 600 is detachably supported by a support member 700.

[0017] The irradiation optical system 220 and the imaging optical system 240 are housed in a lens barrel 206. The main body 200 is supported by a vibration isolation table 270. The inside of the electron gun chamber 202 and the lens barrel 206 are maintained in a vacuum state by a vacuum exhaust system 500. The electron gun chamber 202 is provided with a chamber door 204 for accessing the inside of the electron gun chamber 202.

[0018] In the main body 200, the irradiation optical system 220 focuses the electron beam emitted from the electron source 210 to form an electron probe and deflects the electron beam. This allows the electron probe to scan the sample S. In the transmission electron microscope 2, a STEM image can be acquired by detecting electrons that have transmitted through the sample S with a detector 260 while the electron probe is scanned across the sample S. In addition, in the transmission electron microscope 2, the irradiation optical system 220 irradiates the sample S with a parallel electron beam, the imaging optical system 240 forms a TEM image using the electrons that have transmitted through the sample S, and the imaging device 250 can capture the TEM image.

[0019] The configuration of the main body 200 is not particularly limited, and may include, for example, various detectors, various spectroscopes, various manipulators, etc. For example, the main body 200 may include an EDS detector for performing measurements using energy dispersive X-ray spectroscopy (EDS).

[0020] The sample S is supported in the microscope column 206 by a sample holder 300. The sample holder 300 is inserted into an insertion opening of the holder support part 230. The sample holder 300 can be inserted into and removed from the insertion opening of the holder support part 230. Therefore, the sample holder 300 can be attached to and detached from the holder support part 230.

[0021] The control unit 400 controls each part of the transmission electron microscope 2. The control unit 400 includes, for example, a processor such as a CPU (Central Processing Unit) and a storage device (memory) such as a RAM (Random Access Memory) and a ROM (Read Only Memory). The storage device stores programs and data for performing various controls. The functions of the control unit 400 can be realized by executing the programs with the processor. The control unit 400 may be realized, for example, by a general-purpose circuit such as a microcontroller or microprocessor that operates according to a program, or by an application specific integrated circuit (ASIC). Alternatively, the above-described circuit may be realized by a dedicated circuit such as a synchronous circuit.

[0022] The vacuum exhaust system 500 evacuates the electron gun chamber 202, the space inside the lens barrel 206, and the space in which the imaging device 250 and the detector 260 are disposed. The vacuum exhaust system 500 is controlled by the control unit 400. Note that the computer functioning as the control unit 400 and the vacuum exhaust system 500 may be located outside the housing 100.

[0023] 1.2. Housing FIG. 2 is a perspective view that schematically shows the housing 100. As shown in FIG. 2, the housing 100 has a rectangular parallelepiped shape. The housing 100 includes a plurality of metal plates. The metal plates are metal plates. The housing 100 covers the main body 200 with the plurality of metal plates. Therefore, the main body 200 cannot be seen from outside the housing 100. Note that the housing 100 may include a plurality of resin plates, and the main body 200 may be covered with the plurality of resin plates.

[0024] FIG. 3 is a front view schematically showing the transmission electron microscope 2. As shown in FIG.

[0025] As shown in Figures 2 and 3, a recess 110 is formed in the housing 100. The recess 110 is provided on a side surface 102 of the housing 100. The side surface 102 forms the front surface of the housing 100. An exchange port 120 is formed at the bottom of the recess 110. The exchange port 120 is an opening for the sample holder 300 to access the insertion port of the holder support part 230.

[0026] 4 is a diagram schematically illustrating a state in which the housing door 104 of the housing 100 is open. The housing door 104 is provided on a side surface 103 of the housing 100. By opening the housing door 104, it is possible to access a chamber door 204 provided in the electron gun chamber 202.

[0027] 1.3. Electron gun chamber 5 and 6 are perspective views schematically showing the electron gun chamber 202. Note that Fig. 5 illustrates a state in which the chamber door 204 is closed, and Fig. 6 illustrates a state in which the chamber door 204 is open.

[0028] 5 and 6, chamber door 204 is provided on the side wall of electron gun chamber 202. Replacement opening 202a penetrating the side wall is provided in the side wall of electron gun chamber 202, and replacement opening 202a can be airtightly closed by chamber door 204. O-ring 203 is attached to chamber door 204, and O-ring 203 can airtightly seal the gap between chamber door 204 and the side wall of electron gun chamber 202.

[0029] FIG. 7 is a perspective view schematically showing the electron gun chamber 202, the support member 700, and the filament unit 600. As shown in FIG.

[0030] As shown in FIG. 7, the transmission electron microscope 2 includes a filament unit 600 and a support member 700 that supports the filament unit 600.

[0031] The electron gun chamber 202 includes a cylindrical side wall, a flange that closes the top of the side wall, and a base that closes the bottom of the side wall and has a passage for the electron beam.

[0032] The filament unit 600 is supported in the electron gun chamber 202 by a support member 700. The support member 700 detachably supports the filament unit 600 in the electron gun chamber 202. The support member 700 is provided on the side wall of the electron gun chamber 202. The support member 700 is connected to the side wall of the electron gun chamber 202. The support member 700 is inserted into a through-hole 202 b provided in the side wall of the electron gun chamber 202 .

[0033] The support member 700 extends from the side wall of the electron gun chamber 202 toward the center of the electron gun chamber 202. The extension direction D of the support member 700 is perpendicular to the optical axis A of the electron source 210. The extension direction D of the support member 700 is the horizontal direction, and the optical axis A of the electron source 210 is the vertical direction. The electron source 210 is located, for example, on the central axis of the cylindrical electron gun chamber 202. The optical axis A of the electron source 210 is located, for example, on the central axis of the electron gun chamber 202.

[0034] When the extension direction D of the support member 700 is defined as a first direction, the chamber door 204 is located in the first direction of the support member 700. In other words, the chamber door 204 is located in the extension direction D of the support member 700 when viewed from the support member 700. The replacement port 202a in which the chamber door 204 is provided and the through-hole 202b into which the support member 700 is inserted are opposite each other.

[0035] The support member 700 includes a pipe 710, an insulator 720, a flange 722, and a mounting portion 730. The pipe 710 is inserted into the through-hole 202b. The pipe 710 and the side wall of the electron gun chamber 202 are joined by welding or the like.

[0036] The insulator 720 is housed in the pipe 710. A flange 722 is joined to the end of the pipe 710. The insulator 720 is fixed to the flange 722. The insulator 720 supports a high-voltage cable for supplying power to the electron source 210. The high-voltage cable is connected to a high-voltage power supply. The high-voltage power supply is a power supply that generates a negative high voltage to accelerate electrons emitted from the electron source 210. The insulator 720 insulates the high-voltage cable.

[0037] The insulator 720 extends from the side wall of the electron gun chamber 202 toward the center of the electron gun chamber 202. The insulator 720 is, for example, cylindrical, and the central axis of the insulator 720 is parallel to the extension direction D. An attachment portion 730 for attaching the filament unit 600 is provided at the tip of the insulator 720.

[0038] By attaching the filament unit 600 to the attachment portion 730, the electron source 210 is placed at the center of the electron gun chamber 202. In this way, the filament unit 600 is positioned by attaching it to the attachment portion 730. In other words, by attaching the filament unit 600 to the attachment portion 730, the optical axis A of the electron source 210 can be aligned with the optical axis of the irradiation optical system 220.

[0039] FIG. 8 is a perspective view schematically showing the bottom of the electron gun chamber 202. As shown in FIG.

[0040] A two-stage deflection alignment coil 208 is provided on a base portion located at the bottom of the electron gun chamber 202. The two-stage deflection alignment coil 208 is capable of two-dimensionally deflecting the electron beam. The two-stage deflection alignment coil 208 is used to correct deviation of the optical axis A of the electron source 210 from the optical axis of the irradiation optical system 220. As shown in FIG. 8 , the filament unit 600 is provided with a pin insertion hole 640 for fixing the filament unit 600 to a jig, which will be described later.

[0041] 1.4. Filament unit Fig. 9 is a cross-sectional perspective view schematically showing the filament unit 600. Fig. 10 is an exploded perspective view schematically showing the filament unit 600.

[0042] As shown in Figures 9 and 10, the filament unit 600 includes an electron source 210, a base 602, a socket 604a, a socket 604b, a connection terminal 606a, a connection terminal 606b, a Wehnelt 608, a fixing ring 610, and an anti-rotation member 620 (an example of an engagement portion).

[0043] The electron source 210 is, for example, a tungsten filament. When a current is passed through the tungsten filament, it is heated and can emit thermoelectrons. One end of the electron source 210 is connected to a connection pin, which is inserted into the socket 604a. Similarly, the other end of the electron source 210 is connected to a connection pin, which is inserted into the socket 604b.

[0044] A socket 604a, a socket 604b, a connection terminal 606a, and a connection terminal 606b are fixed to the base 602. The socket 604a and the connection terminal 606a are electrically connected. The socket 604b and the connection terminal 606b are electrically connected. Therefore, one end of the electron source 210 is electrically connected to the connection terminal 606a, and the other end of the electron source 210 is electrically connected to the connection terminal 606b.

[0045] A bias voltage is applied to the Wehnelt 608. The amount of electron current emitted from the electron source 210 can be controlled by the bias voltage applied to the Wehnelt 608. The Wehnelt 608 is fixed to the base 602 by a fixing ring 610. A plurality of exhaust holes are formed in the Wehnelt 608. This allows the periphery of the electron source 210 to be efficiently evacuated. The plurality of exhaust holes are provided symmetrically with respect to the optical axis A of the electron source 210.

[0046] The anti-rotation member 620 is fixed to the base 602. The anti-rotation member 620 has a protrusion 622 and a protrusion 624.

[0047] Fig. 11 is a perspective view schematically showing the state in which the filament unit 600 is attached to the attachment portion 730 of the support member 700. Fig. 12 is a perspective view schematically showing the state in which the filament unit 600 is attached to the attachment portion 730 of the support member 700.

[0048] The mounting portion 730 is provided with guide grooves 732 and 734 extending in the extension direction D of the support member 700. As shown in FIG. 11 , by fitting the protrusion 622 into the guide groove 732 and the protrusion 624 into the guide groove 734, the filament unit 600 can be moved linearly along the extension direction D without rotating. In this way, the guide grooves 732 and 734 function as guides for guiding the filament unit 600 to the center of the electron gun chamber 202, and the protrusions 622 and 624 function as engaging portions that engage with the guides. Therefore, the filament unit 600 can be moved linearly along the extension direction D of the support member 700, and the filament unit 600 can be positioned.

[0049] FIG. 13 is a perspective view schematically showing the filament unit 600 attached to the attachment portion 730 of the support member 700. As shown in FIG.

[0050] 13, the support member 700 has terminals 722a and 722b. The terminals 722a and 722b are electrically connected to a high-voltage power supply via a high-voltage cable. The terminals 722a and 722b are held by an insulator 720. The terminals 722a and 722b protrude from the tip of the insulator 720 in the extension direction D.

[0051] By attaching the filament unit 600 to the attachment portion 730, the terminal 722a The connection terminal 606a of the filament unit 600 is inserted into the terminal 722a, and the connection terminal 606b of the filament unit 600 is inserted into the terminal 722b. As a result, the connection terminal 606a is electrically connected to the terminal 722a, and the connection terminal 606a is electrically connected to the terminal 722b. For example, the terminals 722a and 722b are sockets, and the connection terminals 606a and 606b are electrode pins.

[0052] The connection terminal 606a is electrically connected to the terminal 722a, and the connection terminal 606a is electrically connected to the terminal 722b, so that the high voltage power supply and the electron source 210 can be electrically connected.

[0053] FIG. 14 is a diagram illustrating a locking mechanism 740 for fixing the filament unit 600 to the support member 700. As shown in FIG.

[0054] 14, the locking mechanism 740 includes a protruding portion 742 protruding from the tip of the insulator 720 and a clamping portion 630 that clamps the protruding portion 742. The clamping portion 630 is provided in the filament unit 600.

[0055] By pushing the filament unit 600 into the support member 700 from the direction opposite to the extension direction D of the support member 700, the protruding portion 742 is clamped by the clamping portion 630, and the filament unit 600 is fixed to the support member 700. Furthermore, by applying a force to the filament unit 600 in the extension direction D, the protruding portion 742 is released from the clamping portion 630. In this manner, the clamping portion 630 and the protruding portion 742 constitute a locking mechanism 740 for mechanically fixing the filament unit 600. Furthermore, the clamping portion 630 and the protruding portion 742 electrically connect the filament unit 600 and the support member 700. Note that the configuration of the locking mechanism 740 is not limited to the example shown in FIG. 14 .

[0056] In the above, the case where the filament unit 600 includes the electron source 210 and the Wehnelt 608 has been described, but the other configurations of the filament unit 600 are not particularly limited as long as it includes the electron source 210.

[0057] 2. How to replace the filament 2.1. How to replace the filament unit Fig. 15 is a flowchart showing an example of a method for replacing a filament unit. As shown in Fig. 15, the method for replacing a filament unit includes step S10 of opening the housing door 104 of the housing 100, step S20 of opening the chamber door 204, step S30 of removing a first filament unit (an example of a first charged particle source unit) from the support member 700, step S40 of introducing a second filament unit (an example of a second charged particle source unit) into the electron gun chamber 202 through the chamber door 204 and attaching the second filament unit to the support member 700, step S50 of closing the chamber door 204, and step S60 of closing the housing door 104 of the housing 100.

[0058] 2.2. Step S10 of opening the housing door First, as shown in Fig. 4, the housing door 104 of the housing 100 is opened, thereby making it possible to access the chamber door 204.

[0059] 2.3. Step S20 of opening the chamber door Next, as shown in Fig. 6, the chamber door 204 is opened. This allows access to the inside of the electron gun chamber 202. Here, the housing door 104 is provided on the side surface 103 of the housing 100. The chamber door 204 is also provided on the side wall of the electron gun chamber 202. Therefore, the filament unit 600 can be replaced without having to work at a height using a stepladder or the like.

[0060] For example, even in a transmission electron microscope with a height of about 1.8 m, by providing the chamber door 204 on the side wall of the electron gun chamber 202, the position of the chamber door 204 can be set to a height of about 1.6 m. This allows even an operator with a height of about 1.5 m to replace the filament unit 600 by using a step stool of about 0.2 m. Therefore, with the transmission electron microscope 2, working at height is not necessary, and the filament unit 600 can be replaced safely.

[0061] Before step S20 of opening the chamber door 204, the inside of the electron gun chamber 202 and the inside of the electron beam tube 206 are set to atmospheric pressure.

[0062] 2.4. Step S30 of Removing the First Filament Unit from the Support Member 16 and 17 are perspective views schematically showing the jig 800. Fig. 18 is a perspective view schematically showing step S30 of removing the first filament unit 600A. Here, the first filament unit 600A is a used filament unit 600.

[0063] As shown in FIG. 18, a jig 800 is used in the step S30 of removing the first filament unit 600A.

[0064] As shown in FIGS. 16, 17, and 18, the jig 800 includes a unit base 810, a fixing mechanism 820 that fixes the first filament unit 600A, a switching knob 830, a ground electrode 840, and a transmission spring 850.

[0065] The unit base 810 has a notch 812. The notch 812 is shaped so that the first filament unit 600A fits into the notch 812. The first filament unit 600A fitted into the notch 812 is fixed by a fixing mechanism 820.

[0066] The fixing mechanism 820 has a pin insertion hole 640 provided in the first filament unit 600A and a pin 822 that is inserted into the pin insertion hole 640. Multiple balls are fixed to the tip of the pin 822. A shaft that moves within the pin 822 by operation of the switching knob 830 is housed within the pin 822.

[0067] The pin insertion hole 640 has a small diameter portion and a large diameter portion having a diameter larger than that of the small diameter portion. The small diameter portion is formed closer to the entrance of the pin insertion hole 640 than the large diameter portion.

[0068] The switching knob 830 is a knob for switching between a state in which the fixing of the first filament unit 600A is enabled and a state in which the fixing is disabled. By rotating the switching knob 830, it is possible to switch between a state in which the fixing is enabled and a state in which the fixing is disabled. The switching knob 830 is connected to the pin 822.

[0069] When the switching knob 830 is rotated to enable the fixation, the balls fixed to the tip of the pin 822 are pushed outward from the pin 822 by the shaft, and the balls become caught in the step between the small diameter portion and the large diameter portion of the pin insertion hole 640. This allows the first filament unit 600A to be fixed to the unit base 810.

[0070] When the switching knob 830 is rotated to disable the locking, the balls enter the pin 822, and the pin 822 can pass through the small diameter portion of the pin insertion hole 640. This allows the locking of the first filament unit 600A to be released.

[0071] The means by which the fixing mechanism 820 fixes the first filament unit 600A is not particularly limited. It will not be done.

[0072] 18 , the ground electrode 840 is electrically connected to the first filament unit 600A fixed to the unit base 810 via a transmission spring 850 and a pin 822. One end of the transmission spring 850 is connected to the ground electrode 840, and the other end of the transmission spring 850 is connected to the pin 822. Therefore, the ground electrode 840 and the first filament unit 600A can be electrically connected by the transmission spring 850 and the pin 822. The transmission spring 850 and the pin 822 function as wiring for electrically connecting the first filament unit 600A and the ground electrode 840.

[0073] In step S30 of removing the first filament unit 600A from the support member 700, first, the jig 800 is attached to the first filament unit 600A supported by the support member 700. Specifically, with the fixing disabled, the first filament unit 600A is fitted into the notch 812. Next, the state is switched to enable fixing using the switching knob 830. This fixes the jig 800 to the first filament unit 600A.

[0074] Next, the jig 800 is gripped, and a force greater than the force with which the locking mechanism 740 holds the first filament unit 600A is applied in the extension direction D of the support member 700, thereby pulling out the first filament unit 600A from the support member 700. This allows the first filament unit 600A to be removed from the support member 700. At this time, the connection terminal 606a is detached from the terminal 722a, and the connection terminal 606b is detached from the terminal 722b.

[0075] The first filament unit 600A with the jig 800 attached thereto is taken out of the electron gun chamber 202 through the replacement opening 202a. Here, as shown in FIG. 18 , when the jig 800 passes through the replacement opening 202a, the ground electrode 840 is brought into contact with the electron gun chamber 202. This allows the charge accumulated in the first filament unit 600A to flow to the ground. Because the ground electrode 840 is provided on the bottom of the unit base 810, it is easy to bring the ground electrode 840 into contact with the side wall of the electron gun chamber 202.

[0076] 2.5. Step S40 of attaching the second filament unit to the support member 19 is a perspective view schematically illustrating step S30 of attaching the second filament unit 600B. Here, the second filament unit 600B is a brand new, unused filament unit 600. Note that the second filament unit 600B may be one in which the filament of the first filament unit 600A has been replaced with a new filament.

[0077] In step S40 of attaching the second filament unit 600B to the support member 700, first, a jig 800 is attached to the second filament unit 600B. Next, the jig 800 is grasped, and the second filament unit 600B to which the jig 800 is attached is introduced into the electron gun chamber 202 through the replacement port 202a.

[0078] 11 , the protrusion 622 is fitted into the guide groove 732 of the support member 700, the protrusion 624 is fitted into the guide groove 734, and the second filament unit 600B is pushed in the direction opposite to the extension direction D of the support member 700. As a result, the second filament unit 600B moves while being guided by the guide groove 732 and the guide groove 734, and is positioned at the center of the electron gun chamber 202.

[0079] At this time, the connection terminal 606a is inserted into the terminal 722a, and the connection terminal 606b is inserted into the terminal 722b, as shown in Fig. 13. This electrically connects the second filament unit 600B and the high-voltage power supply.

[0080] Next, the jig 800 is removed from the second filament unit 600B. Through the above steps, the second filament unit 600B can be attached to the support member 700.

[0081] 2.6. Step S50 of Closing the Chamber Door Next, as shown in FIG. 5, the chamber door 204 is closed.

[0082] 2.7. Step S60 of Closing the Enclosure Door Next, as shown in FIG. 2, the housing door 104 is closed.

[0083] The filament unit 600 can be replaced by the above steps.

[0084] 3. Effects The transmission electron microscope 2 includes an electron gun chamber 202, a filament unit 600 having an electron source 210, a support member 700 provided on a side wall of the electron gun chamber 202 and detachably supporting the filament unit 600 within the electron gun chamber 202, and a chamber door 204 provided on the side wall of the electron gun chamber 202 for accessing the inside of the electron gun chamber 202. In this way, in the transmission electron microscope 2, the filament unit 600 can be removed or introduced through the chamber door 204 provided on the side wall of the electron gun chamber 202, making it easier to replace the filament unit 600 than, for example, lifting up the electron gun chamber 202 to replace the filament unit 600.

[0085] For example, when lifting up the electron gun chamber 202 to replace the filament unit 600, it is necessary to access the top of the transmission electron microscope, which requires working at a height. In contrast, in the transmission electron microscope 2, the chamber door 204 is provided on the side wall of the electron gun chamber 202, so the filament unit 600 can be replaced safely without working at a height using a stepladder or the like.

[0086] In the transmission electron microscope 2, the support member 700 extends from the side wall of the electron gun chamber 202 toward the center of the electron gun chamber 202, and the filament unit 600 is pushed into the support member 700 from the direction opposite to the extension direction D of the support member 700. In this way, in the transmission electron microscope 2, the direction in which the filament unit 600 is pushed into the support member 700 is along the extension direction D of the support member 700, so that excessive force can be prevented from being applied to the joint between the support member 700 and the electron gun chamber 202 when the filament unit 600 is pushed in. This reduces the possibility of the support member 700 being damaged. For example, if the extension direction of the support member 700 and the direction in which the filament unit 600 is pushed in are perpendicular, excessive force may be applied to the joint between the support member 700 and the electron gun chamber 202, potentially damaging the support member 700.

[0087] In the transmission electron microscope 2, the support member 700 has guide grooves 732 and 734 extending in the extension direction D, and the filament unit 600 has a protrusion 622 that engages with the guide groove 732 and a protrusion 624 that engages with the guide groove 734. Therefore, when attaching the filament unit 600 to the support member 700, the filament unit 600 can be pushed in a direction along the extension direction D of the support member 700. This reduces the possibility of the support member 700 being damaged.

[0088] In the transmission electron microscope 2, the support member 700 extends in a first direction from the side wall of the electron gun chamber 202, and the chamber door 204 is located in the first direction of the support member 700. Therefore, in the transmission electron microscope 2, the filament unit 600 can be easily attached to the support member 700. It can be done.

[0089] In the transmission electron microscope 2, the support member 700 includes an insulator 720, which holds a first terminal (terminals 722a and 722b) electrically connected to a high-voltage power supply. The filament unit 600 also has a second terminal (connection terminals 606a and 606b) electrically connected to the electron source 210. Attaching the filament unit 600 to the support member 700 electrically connects the first terminal and the second terminal. That is, attaching the filament unit 600 to the support member 700 electrically connects the terminal 722a and the connection terminal 606a, and electrically connects the terminal 722b and the connection terminal 606b. Therefore, in the transmission electron microscope 2, attaching the filament unit 600 to the support member 700 electrically connects the electron source 210 and the high-voltage power supply.

[0090] The transmission electron microscope 2 has an irradiation optical system 220 for irradiating the sample S with an electron beam, and an imaging optical system 240 for forming an image with electrons transmitted through the sample S. Therefore, in the transmission electron microscope 2, the lens barrel 206 is high, but because the chamber door 204 is provided on the side wall of the electron gun chamber 202, the filament unit 600 can be replaced safely without having to work at a height using a stepladder or the like.

[0091] The transmission electron microscope 2 includes a housing 100 that houses the electron gun chamber 202 and the column 206, and a housing door 104 for accessing the chamber door 204 is provided on a side surface 103 of the housing 100. In this way, in the transmission electron microscope 2, since the housing door 104 is provided on the side surface 103 of the housing 100, the chamber door 204 provided on the side wall of the electron gun chamber 202 can be easily accessed.

[0092] The method for replacing the filament unit 600 in the transmission electron microscope 2 includes the steps of opening the chamber door 204, removing the first filament unit 600A from the support member 700, and introducing the second filament unit 600B into the electron gun chamber 202 through the chamber door 204 and attaching the second filament unit 600B to the support member 700. In this way, the method for replacing the filament unit 600 allows the first filament unit 600A to be removed from the chamber door 204 and the second filament unit 600B to be introduced, making it possible to easily replace the filament unit 600.

[0093] Furthermore, since the chamber door 204 is provided on the side wall of the electron gun chamber 202, as described above, when replacing the filament unit 600, the filament unit 600 can be replaced safely without having to work at height.

[0094] In the method for replacing the filament unit 600 in the transmission electron microscope 2, in the step of removing the first filament unit 600A, a jig 800 is attached to the first filament unit 600A supported by the support member 700, and the first filament unit 600A is removed from the support member 700 by gripping the jig 800. Therefore, the operator can remove the first filament unit 600A without touching the first filament unit 600A.

[0095] For example, the first filament unit 600A is hot immediately after use, and there is a risk of burns if the worker touches it directly. Therefore, in order to remove the first filament unit 600A from the support member 700, it was necessary to wait until the first filament unit 600A had cooled down sufficiently. In contrast, with the above-described method for replacing the filament unit 600, the worker can remove the first filament unit 600A from the support member 700 without touching it, so the worker can easily remove the first filament unit 600A even immediately after use. The first filament unit 600A can now be safely removed.

[0096] In the method for replacing the filament unit 600 in the transmission electron microscope 2, the jig 800 includes a ground electrode 840 and a transmission spring 850 that functions as wiring that electrically connects the first filament unit 600A attached to the jig 800 to the ground electrode 840. Furthermore, in the step of removing the first filament unit 600A, the first filament unit 600A and the ground electrode 840 are electrically connected, and the ground electrode 840 is brought into contact with the electron gun chamber 202. Therefore, in the method for replacing the filament unit 600, the charge accumulated in the first filament unit 600A can be discharged to the ground, reducing the possibility of the operator receiving an electric shock.

[0097] In the method for replacing the filament unit 600 in the transmission electron microscope 2, the support member 700 extends from the side wall of the electron gun chamber 202 toward the center of the electron gun chamber 202. In addition, in the step of attaching the second filament unit 600B to the support member 700, the second filament unit 600B is pushed into the support member 700 in the direction opposite to the extension direction D. This reduces the possibility of the support member 700 being damaged.

[0098] The method for replacing the filament unit 600 in the transmission electron microscope 2 includes a step of opening the housing door 104 before a step of opening the chamber door 204. The housing door 104 is provided on the side surface 103 of the housing 100, allowing easy access to the chamber door 204 provided on the side wall of the electron gun chamber 202.

[0099] 4. Processing of the control section 4.1. Increasing the accelerating voltage In the transmission electron microscope 2, a voltage boosting process for applying an acceleration voltage (hereinafter also referred to as "high voltage") can be automatically performed after replacing the filament unit 600. The voltage boosting process can be performed, for example, immediately after replacing the filament unit 600 and starting evacuation of the electron gun chamber 202 and the electron tube 206.

[0100] The control unit 400 performs a conditioning process during the voltage boosting process. The conditioning process is a process in which the voltage is boosted to a conditioning voltage value, which is an acceleration voltage value higher than the acceleration voltage to be used, and maintained at that value for a certain period of time. In the voltage boosting process, after the conditioning process is performed, the voltage is reduced from the conditioning voltage value to a target acceleration voltage value. By performing the conditioning process, the risk of discharge during use can be reduced.

[0101] 4.2. Boosting process FIG. 20 is a flowchart showing an example of the voltage boosting process of the control unit 400.

[0102] First, the control unit 400 determines whether or not the user has issued an instruction to start automatic voltage increase (step S100). When the user has pressed an automatic voltage increase start button on a GUI (Graphical User Interface), the control unit 400 determines that the user has issued an instruction to start automatic voltage increase.

[0103] When the control unit 400 determines that the user has issued an instruction to start automatic voltage increase (Yes in S100), it determines whether a high voltage is being applied (S102). This is because the voltage increase process is always started under the same conditions, i.e., when no high voltage is being applied. By performing the voltage increase process under the same conditions, it is possible to understand the trends of the device from the data acquired during the voltage increase process.

[0104] When the control unit 400 determines that a high voltage is being applied (Yes in step S102), The operator is notified of the error (step S106), and the boosting process is terminated.

[0105] If the control unit 400 determines that a high voltage is not being applied (No in step S102), it determines whether the device is in a conditioning mode (C mode) that allows a high voltage to be applied at a conditioning voltage value HTc (step S104). The conditioning voltage value HTc is an acceleration voltage that is higher than the target acceleration voltage value. By applying the conditioning voltage value HTc and then reducing the voltage to the target acceleration voltage value, the risk of discharge when used at the target acceleration voltage value can be reduced. Since the device is not in the conditioning mode during normal use, if the device is in the conditioning mode, it is determined to be an abnormality.

[0106] If the control unit 400 determines that the conditioning mode is in effect (Yes in step S104), it notifies the user of an error (step S106) and ends the pressure increase process.

[0107] When it is determined that the conditioning mode is not in effect (No in step S104), the control unit 400 starts the conditioning process.

[0108] Specifically, first, the control unit 400 determines whether an error has occurred in the device (step S108). If the control unit 400 determines that an error has not occurred in the device (No in step S108), the control unit 400 determines whether the user has issued an instruction to cancel the automatic voltage increase process (step S110).

[0109] If the control unit 400 determines that a cancellation instruction has not been issued (No in step S110), it measures the degree of vacuum in the electron gun chamber 202 (step S112). The control unit 400 acquires a measured value of the degree of vacuum in the electron gun chamber 202 from a vacuum gauge for measuring the degree of vacuum in the electron gun chamber 202.

[0110] The control unit 400 stores the measurement value acquired from the vacuum gauge in the memory unit. Furthermore, if the memory unit does not store information on the ultimate vacuum degree, the control unit 400 records the measurement value in the memory unit as the ultimate vacuum degree. If the memory unit stores the ultimate vacuum degree, the control unit 400 compares the ultimate vacuum degree stored in the memory unit with the measurement value, and if the measurement value is higher than the ultimate vacuum degree, updates the ultimate vacuum degree.

[0111] Next, the control unit 400 counts the number of times N that the high voltage application has been turned on. HT is set N times A It is determined whether or not the number of times N when the high voltage application is turned on is exceeded (step S114). HT corresponds to the number of times the high voltage application is turned off. If the number of times the high voltage application is turned off exceeds the set number N A If it exceeds this, there is a high possibility that there is an abnormality in the high voltage power supply, etc.

[0112] The control unit 400 determines the number of times N high voltage is applied. HT Number of times set is N A If it is determined that the voltage does not exceed the threshold voltage (No in step S114), it is determined whether or not the high voltage is applied (step S116).

[0113] If the control unit 400 determines that the application of high voltage is not on (No in step S116), it determines whether the degree of vacuum in the electron gun chamber 202 is equal to or greater than a threshold value (step S118). If the measurement value stored in the storage unit is equal to or greater than the threshold value (Yes in step S118), the control unit 400 turns on the application of high voltage (step S120). After turning on the high voltage power supply, the control unit 400 returns to the processing of step S108.

[0114] On the other hand, if the control unit 400 determines that the measurement value stored in the storage unit is not equal to or greater than the threshold value (No in step S118), the control unit 400 waits for a certain period of time to improve the degree of vacuum, and then performs step S Return to processing 108.

[0115] If the control unit 400 determines that the application of high voltage is on (Yes in step S116), it determines whether or not there is an abnormality in the high-voltage power supply (step S122). If the control unit 400 determines that there is an abnormality in the high-voltage power supply (Yes in step S122), it turns off the application of high voltage (step S123). The control unit 400 turns off the high-voltage power supply and stops the application of high voltage. Then, the control unit 400 returns to step S108.

[0116] If the control unit 400 determines that there is no abnormality in the high-voltage power supply (No in step S122), it determines whether the vacuum in the electron gun chamber 202 has deteriorated (step S124). The control unit 400 acquires the measured value of the degree of vacuum in the electron gun chamber 202 from the vacuum gauge. The control unit 400 compares the measured value with the degree of ultimate vacuum stored in the memory unit, and determines that the vacuum has deteriorated if the measured value is lower than the degree of ultimate vacuum and the difference between the measured value and the degree of ultimate vacuum is equal to or greater than a predetermined value. If the measured value and the degree of ultimate vacuum do not satisfy this relationship, the control unit 400 determines that the degree of vacuum has not deteriorated.

[0117] If the control unit 400 determines that the vacuum has deteriorated (Yes in step S124), it reduces the high pressure by a preset value (step S125). Then, the control unit 400 returns to the process of step S108.

[0118] If the control unit 400 determines that the vacuum has not deteriorated (No in step S124), it determines whether the high pressure has reached the conditioning voltage value HTc (step S126). If the control unit 400 determines that the high pressure has not reached the conditioning voltage value HTc (No in step S126), it increases the high pressure by a preset value (step S127). Then, the control unit 400 returns to the processing of step S108.

[0119] If the control unit 400 determines that the high voltage has reached the conditioning voltage value HTc (Yes in step S126), it determines whether a predetermined time has elapsed since the high voltage reached the conditioning voltage value HTc (step S128). The predetermined time is, for example, 10 minutes. The predetermined time can be set to any time.

[0120] When the control unit 400 determines that the predetermined time has not elapsed since the high voltage reached the conditioning voltage value HTc (No in step S128), the control unit 400 returns to the processing in step S108.

[0121] The control unit 400 determines that a predetermined time has elapsed since the high voltage reached the conditioning voltage value HTc (Yes in step S128), that an error has occurred in the device (Yes in step S108), that an instruction to cancel has been given (Yes in step S110), or that the number of times N when the application of high voltage has been turned on has elapsed. HT is set N times A If it is determined that the difference is exceeded (Yes in step S114), the conditioning process ends.

[0122] After the conditioning process is completed, the control unit 400 determines whether an error has occurred in the device or the process has been canceled (step S130). If the control unit 400 determines that an error has occurred in the device (Yes in step S108), if the control unit 400 determines that a cancellation instruction has been issued (Yes in step S110), or if the number of times N when the high voltage application has been turned on has elapsed, HT is set N times A If it is determined that the voltage has exceeded the threshold (Yes in step S114), it is determined that an error has occurred in the device or the process has been canceled (No in step S130), and the high voltage is turned off (step S134), ending the boost process.

[0123] If the control unit 400 determines that a predetermined time has elapsed since the high voltage reached the conditioning voltage value HTc (Yes in step S128), it determines that there is no device error or cancellation of the process (No in step S130), and reduces the acceleration voltage to the target acceleration voltage value (step S132). This allows the acceleration voltage to be set to the target acceleration voltage value. After reducing the acceleration voltage to the target acceleration voltage value, the control unit 400 ends the voltage increase process.

[0124] 4.3. Start function The risk of discharge is low if the acceleration voltage used is not the maximum acceleration voltage, or if the time the inside of the electron gun chamber 202 or the inside of the electron tube 206 is exposed to the atmosphere is short when replacing the filament unit 600. In this case, the start function may be used without performing the conditioning process described above. The start function optimizes the acceleration voltage, filament, and optical system conditions to the conditions set by the user, making the device ready for immediate observation.

[0125] The boosting function using the start function is intended for daily use by the user and is not suitable for use when there is outgassing from the electron gun chamber 202 or filament unit 600 or when dust or other particles are attached. If there is a risk of discharge, use the conditioning function described above. The transmission electron microscope 2 has two automatic boosting methods that are tailored to the state of the device, minimizing downtime while minimizing the user's need to use the device.

[0126] 4.4. Start process FIG. 21 is a flowchart showing an example of the start process of the control unit 400.

[0127] First, the control unit 400 determines whether or not the user has issued an instruction to start the start process (step S200). When the user has pressed the start process start button on the GUI, the control unit 400 determines that the user has issued an instruction to start the start process.

[0128] Before starting the start process, the user selects the target acceleration voltage value and observation conditions on the GUI screen. For example, the user can select the acceleration voltage value and observation conditions from pull-down menus on the GUI screen.

[0129] When the control unit 400 determines that the user has issued an instruction to start the start process (Yes in step S200), it initializes the settings of specific items (step S201). For example, if beam blanking is on, the control unit 400 turns it off. If the image field is not "Bright," it sets it to "Bright." If "IOS off" is on, it turns it off. Also, it turns all wobblers off.

[0130] By initializing these items, you can always start observation in the same state, even if the previous user ended it with different settings.

[0131] Next, the control unit 400 checks for an abnormality in the device (step S202). If the control unit 400 determines that an abnormality has occurred in the device and that the abnormality cannot be resolved by resetting the device, it determines that an abnormality has occurred in the device (Yes in step S202) and ends the start process. If the control unit 400 determines that the abnormality in the device can be resolved by resetting the device, it resets the device and checks for an abnormality in the device again.

[0132] When the control unit 400 determines that there is no abnormality in the apparatus (No in step S202), the control unit 400 determines whether the degree of vacuum in the electron gun chamber 202 and the electron beam tube 206 is at a level at which it is possible to start increasing the pressure. The control unit 400 determines whether the degree of vacuum has reached a level at which it is possible to start increasing the pressure (step S204). If the degree of vacuum has not reached a level at which it is possible to start increasing the pressure, the control unit 400 sets a waiting time of a certain period of time, and then determines again whether the degree of vacuum has reached a level at which it is possible to start increasing the pressure. If the degree of vacuum has not reached a level at which it is possible to start increasing the pressure even after waiting for the certain period of time, the control unit 400 determines that there is an abnormality in the device (Yes in step S206) and ends the start process.

[0133] When the control unit 400 determines that the degree of vacuum has reached a level at which it is safe to start increasing the pressure and that there is no abnormality in the degree of vacuum (No in step S206), it starts energizing the multiple electron lenses that make up the irradiation optical system 220 and the imaging optical system 240 (S208). This makes the irradiation optical system 220 and the imaging optical system 240 available for use.

[0134] Here, in order to use the transmission electron microscope 2, it is necessary to pass a current through the electron lens. However, it is desirable to stop the current passing through the electron lens when the transmission electron microscope 2 is not in use. This is because maintaining the current passing through the electron lens consumes a great deal of power and places a heavy burden on the environment. Therefore, when the transmission electron microscope 2 is not in use, the current passing through the electron lens is stopped, and in step S208, current is started to pass through the electron lens. If the predetermined current is not passing through the electron lens, the control unit 400 determines that there is an abnormality in the device (Yes in step S210) and ends the start process.

[0135] If the control unit 400 determines that a predetermined current flows through the electron lens and that there is no abnormality in the electron lens (No in step S210), it increases the acceleration voltage to a target acceleration voltage value (step S212).

[0136] Here, the target acceleration voltage value is set using a pull-down menu on the GUI screen. The control unit 400 increases the acceleration voltage so that the acceleration voltage reaches the set target acceleration voltage value. When increasing the acceleration voltage using the start function, a mechanism is provided for adjusting the acceleration voltage while increasing the voltage so as not to cause discharge. This mechanism will be described later in "4.5. Voltage Increase Processing S212."

[0137] If the acceleration voltage cannot be increased to the target acceleration voltage value, the control unit 400 determines that there is an abnormality in the high voltage system (Yes in step S214), and ends the start process.

[0138] If the control unit 400 determines that the acceleration voltage has been increased to the target acceleration voltage value and that there is no abnormality in the high voltage system (No in step S214), it causes the electron source 210 to generate an electron beam (step S216).

[0139] The control unit 400 first determines whether the specimen holder 300 is inserted into the holder support unit 230. If the specimen holder 300 is not inserted, the control unit 400 determines that microscopy will not be performed immediately and skips steps S216 and S218. In this case, no current is applied to the filament.

[0140] When the control unit 400 determines that the sample holder 300 is inserted, it starts energizing the electron source 210, that is, energizing the filament. At this time, if no current flows through the filament despite energization, the control unit 400 determines that the filament is broken (Yes in step S218) and ends the start process.

[0141] When the control unit 400 determines that a current is flowing through the filament, it applies a high voltage to start emitting an electron beam. The control unit 400 determines whether or not the target emission current has been reached. If the target emission current has not been reached even after a predetermined time has elapsed, the control unit 400 If not, it is determined that there is an abnormality in the device (Yes in step S218), and the start process is terminated.

[0142] When the control unit 400 determines that an electron beam with a target emission current has been emitted (No in step S218), it inserts the detector in accordance with the use mode (step S220).

[0143] The control unit 400 inserts a detector according to the usage mode set in advance by the user on the GUI screen. The control unit 400 first determines whether the specimen holder 300 is inserted into the holder support unit 230. If the specimen holder 300 is not inserted, the control unit 400 determines that microscopy will not be performed immediately and skips step S220. In this case, the detector is not inserted.

[0144] When the control unit 400 determines that the sample holder 300 is inserted, it inserts a detector according to the set usage mode. For example, although not shown, if the TEM mode is set, it ejects the scan detector off the optical axis and inserts a fluorescent screen onto the optical axis. Furthermore, for example, although not shown, if the EDS measurement mode is set, it inserts an EDS detector.

[0145] Next, the control unit 400 sets the optical conditions (step S222).

[0146] The control unit 400 controls the irradiation optical system 220 and the imaging optical system 240 to achieve the set optical conditions. When the imaging mode used is TEM mode, the control unit 400 initializes the function that keeps the brightness on the sample surface constant regardless of the magnification (brightness magnification link function). This allows the user to start using the system under the same conditions regardless of the conditions under which the system was last used.

[0147] The control unit 400 first determines whether the specimen holder 300 is inserted into the holder support unit 230. If the specimen holder 300 is not inserted, the control unit 400 determines that microscopy will not be performed immediately and skips step S222. If the control unit 400 determines that the specimen holder 300 is inserted, it changes the imaging mode to one that corresponds to the set optical conditions. Next, the control unit 400 initializes the brightness magnification link function. Note that the initialization of the brightness magnification link function will be described later. Next, the deflector system is set to the default value, and the observation magnification is changed to the set value. The optical conditions can be set by the above processing.

[0148] To initialize the brightness magnification link function, first change to Mag mode and set the magnification to the lowest magnification. Next, change the spot size and initialize the excitation value of the condenser lens. Next, insert the objective lens aperture onto the optical axis and set the objective lens focus value to the default value. Finally, initialize LOW Mag mode in the same way. The brightness magnification link function can be initialized by performing the above process.

[0149] Next, the control unit 400 checks for an abnormality in the device (step S224). If the control unit 400 determines that an abnormality exists in the device and that the abnormality cannot be resolved by resetting the device, it determines that an abnormality exists in the device (Yes in step S224) and ends the start process. If the control unit 400 determines that the abnormality can be resolved by resetting the device, it resets the device and checks for an abnormality in the device again.

[0150] When the control unit 400 determines that there is no abnormality in the device (No in step S224), it acquires a map image (step S226). The map image is an image obtained by capturing the entire field of view of the sample S. The control unit 400 displays the captured map image on the GUI screen. This map The image shows the user's current observation location, allowing them to understand which area they are observing. They can also determine which points they should observe from the map image.

[0151] The control unit 400 first determines whether or not the specimen holder 300 is inserted into the holder support unit 230. If the specimen holder 300 is not inserted, the control unit 400 determines that microscopy will not be performed immediately and skips step S226.

[0152] The control unit 400 determines whether a map image has already been acquired, and if so, skips step S226. Next, the control unit 400 opens the beam shutter and sets the magnification to the minimum. Next, the control unit 400 changes the spot size (the size of the electron beam). Next, the control unit 400 changes the excitation value of the condenser lens to adjust the brightness. Next, the control unit 400 moves all apertures away from the optical axis. Next, the control unit 400 adjusts the position of the sample S and captures a map image with the imaging device 250. After capturing the map image, the control unit 400 returns the optical system conditions to the state before step S226 was performed. Finally, the control unit 400 closes the beam shutter. Through the above processing, the map image can be acquired. After capturing the map image, the control unit 400 ends the start processing.

[0153] 4.5. Boost process S212 Figure 22 shows the acceleration voltage V ACC 22 is a diagram for explaining a power supply circuit 900 for applying a high voltage. As shown in FIG. 22, the power supply circuit 900 includes a high voltage generating circuit 910 (high voltage power supply), a load current detecting circuit 920, and a filter circuit 930.

[0154] To generate a high voltage, a small load current I L It is necessary to flow the load current I L flows through a filter circuit 930 that removes high frequency noise and a high voltage generating circuit 910, and is detected as a load current I L The current value is monitored.

[0155] 23 is a diagram for explaining the power supply circuit 900 when a discharge occurs. When a discharge occurs during voltage boosting, the discharge current I Dis the load current I L The load current I L has a theoretical value according to the acceleration voltage value, so the load current I L By comparing the actual current value with the theoretical value, it is possible to detect an increase in the current value due to a small discharge, thereby enabling voltage boosting while avoiding discharge.

[0156] FIG. 24 is a flowchart showing an example of the boosting process S212 of the control unit 400.

[0157] When the control unit 400 starts the voltage boosting process S212, first, the load current I measured by the load current detection circuit 920 is L The control unit 400 acquires the measured value of the load current I L It is determined whether the measured value is smaller than the blood pressure reduction reference (S302).

[0158] The control unit 400 controls the load current I L If the measured value is equal to or greater than the blood pressure reduction standard, that is, I L If the voltage drop criteria are not met (No in step S302), it is assumed that discharge is occurring, and the acceleration voltage V ACC The control unit 400 decreases the acceleration voltage V ACC is decreased by the predetermined value (after step S304), the process returns to step S300.

[0159] The control unit 400 controls the load current I L If the measured value is less than the step-down criterion, i.e., I L If the blood pressure drop criterion is met (Yes in step S302), it is determined whether the measured value is smaller than the maintenance criterion (S306).

[0160] The control unit 400 controls the load current I L If the measured value is equal to or greater than the maintenance standard, that is, I L <maintain If the criteria are not met (No in step S306), it is assumed that a discharge is occurring, and the acceleration voltage V ACCThe control unit 400 maintains the accelerating voltage V for a predetermined time (S308). ACC is maintained for a predetermined time (after step S308), the process returns to step S300.

[0161] The control unit 400 controls the load current I L If the measured value of is less than the maintenance criterion, i.e., I L If the maintenance criteria are met (Yes in step S306), the acceleration voltage V ACC In this way, the control unit 400 increases the load current I L If the measured value is smaller than the voltage drop criterion and smaller than the maintenance criterion, the accelerating voltage V ACC The pressure is increased by a preset value. The maintenance standard value is smaller than the pressure decrease standard value. The pressure decrease standard value and the maintenance standard value can be set to any value.

[0162] Next, the control unit 400 adjusts the acceleration voltage V ACC The control unit 400 determines whether the acceleration voltage V has reached the target acceleration voltage value (step S312). ACC If it is determined that the acceleration voltage V has not reached the target acceleration voltage value (No in step S312), the process returns to step S300. ACC The processes of steps S300, S302, S304, S306, S308, S310, and S312 are repeated until the acceleration voltage value reaches the target value.

[0163] The control unit 400 controls the accelerating voltage V ACC When it is determined that the acceleration voltage value has reached the target acceleration voltage value (Yes in step S312), the voltage boosting process S212 ends.

[0164] The control unit 400 controls the load current I LBefore the process S300 of measuring the voltage, the control unit 400 may check for an abnormality in the device. If the control unit 400 determines that there is an abnormality in the device (Yes in step S214), it terminates the start process. Furthermore, if the control unit 400 is unable to complete the boosting process S212 within a predetermined number of repetitions, it may determine that there is an abnormality in the device (Yes in step S214) and terminate the start process. Furthermore, if the control unit 400 is unable to complete the boosting process S212 within a predetermined time, it may determine that there is an abnormality in the device (Yes in step S214) and terminate the start process.

[0165] 25 is a diagram showing an example of the boost / buck operation of the acceleration voltage. L If the measured value of is within the standard, that is, the load current I L If the measured value is smaller than the maintenance standard, the load current I L The measurement of the load current I L When a rise in occurs, the load current I L In the example shown in Figure 25, the load current I L Since the measured value of exceeds the step-down standard, the acceleration voltage V ACC The acceleration voltage V ACC After the voltage drop operation of L Measure the load current I L If the measured value is smaller than the maintenance standard, the acceleration voltage V ACC Resume boosting.

[0166] Effects In the transmission electron microscope 2, when replacing the filament unit 600, the inside of the electron gun chamber 202 and the inside of the column 206 are exposed to the atmosphere, making it easy for discharge to occur when applying an acceleration voltage. Conventionally, in order to safely increase the acceleration voltage, an operator had to carefully apply a high voltage and perform aging after the degree of vacuum inside the column 206 had become sufficiently high. Here, aging is a process in which an acceleration voltage higher than the acceleration voltage to be used is applied to reduce the risk of discharge at the acceleration voltage to be used.

[0167] In the transmission electron microscope 2, aging can be performed automatically, as shown in Figure 20, so the operator can easily increase the acceleration voltage without being confined to the device. Furthermore, in the transmission electron microscope 2, when aging is not required, the acceleration voltage can be increased using the start function.

[0168] 5. Variations The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0169] For example, in the above-described embodiment, the transmission electron microscope 2 is an electron gun that utilizes thermionic emission, but the transmission electron microscope 2 may be a Schottky electron gun, a cold cathode field emission electron gun, etc. Also, in the above-described embodiment, the case where a filament is used as the electron source 210 is described, but the electron source 210 may be a tungsten single crystal coated with zirconium oxide, which is used in a Schottky electron gun, or a tungsten single crystal, which is used in a cold cathode field emission electron gun.

[0170] Furthermore, the charged particle beam device according to the present invention is not limited to a transmission electron microscope, but may be, for example, a scanning electron microscope or a focused ion beam device. That is, the charged particle beam device according to the present invention includes a charged particle source unit having a charged particle source that generates a charged particle beam such as an electron beam or an ion beam.

[0171] The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the present invention includes configurations that are substantially identical to the configurations described in the embodiments. A substantially identical configuration means, for example, a configuration with the same function, method, and result, or a configuration with the same purpose and effect. The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects or purposes as the configurations described in the embodiments. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments. [Explanation of symbols]

[0172] 2...transmission electron microscope, 100...casing, 102...side surface, 103...side surface, 104...casing door, 110...recess, 120...replacement port, 200...main body, 202...electron gun chamber, 202a...replacement port, 202b...through hole, 203...O-ring, 204...chamber door, 206...lens barrel, 208...alignment coil, 210...electron source, 220...irradiation optical system, 230...holder support section, 240...imaging optical system, 250...imaging device, 260...detector, 270...vibration isolation table, 300...sample holder, 400...control section, 500...vacuum exhaust system, 600...filament unit, 600A...first filament unit, 600B...second filament unit, 602...base, 604a...socket , 604b...socket, 606a...connection terminal, 606b...connection terminal, 608...wehnelt, 610...fixing ring, 620...rotation prevention member, 622...protrusion, 624...protrusion, 630...clamping portion, 640...pin insertion hole, 700...support member, 710...pipe, 720...insulator, 722a...terminal, 722b...terminal, 730...mounting portion, 732...guide groove, 734...guide groove, 740...locking mechanism, 742...protrusion, 800...jig, 810...unit base, 812...notch, 820...fixing mechanism, 822...pin, 830...switching knob, 840...ground electrode, 850...transmission spring, 900...power supply circuit, 910...high voltage generation circuit, 920...load current detection circuit, 930...filter circuit

Claims

1. A chamber; a charged particle source unit having a charged particle source; a support member provided on a side wall of the chamber and configured to detachably support the charged particle source unit within the chamber; a chamber door provided on a side wall of the chamber for accessing the inside of the chamber; A charged particle beam device comprising:

2. In claim 1, the support member extends from a sidewall of the chamber toward a center of the chamber; The charged particle beam device, wherein the charged particle source unit is pushed into the support member from a direction opposite to a direction in which the support member extends.

3. In claim 1, the support member extends from a sidewall of the chamber toward a center of the chamber; the support member has a guide extending in a direction in which the support member extends, The charged particle beam device, wherein the charged particle source unit has an engagement portion that engages with the guide.

4. In claim 1, the support member extends in a first direction from a sidewall of the chamber; The chamber door is positioned in the first direction of the support member.

5. In any one of claims 2 to 4, A charged particle beam device, wherein an optical axis of the charged particle source is perpendicular to a direction in which the support member extends.

6. In claim 1, the support member includes an insulator; the insulator carries a first terminal electrically connected to a power source; the charged particle source unit has a second terminal electrically connected to the charged particle source; The charged particle beam device, wherein the first terminal and the second terminal are electrically connected by attaching the charged particle source unit to the support member.

7. In claim 1, a charged particle beam device including an optical system for irradiating a sample with the charged particle beam emitted from the charged particle source;

8. In claim 1, The charged particle source generates an electron beam.

9. In claim 8, an irradiation optical system for irradiating the sample with the electron beam; an imaging optical system for forming an image of the sample using electrons transmitted through the sample; A charged particle beam device comprising:

10. In claim 9, Including the housing, the housing accommodates a lens barrel that accommodates the irradiation optical system and the imaging optical system, and the chamber; A charged particle beam device, wherein a housing door for accessing the chamber door is provided on a side of the housing.

11. A chamber; a charged particle source unit having a charged particle source; a support member provided on a side wall of the chamber and configured to detachably support the charged particle source unit within the chamber; a chamber door provided on a side wall of the chamber for accessing the inside of the chamber, the method comprising: opening the chamber door; removing a first charged particle source unit from the support member; introducing a second charged particle source unit into the chamber through the chamber door and attaching the second charged particle source unit to the support member; A method for replacing a charged particle source unit, comprising:

12. In claim 11, In the step of removing the first charged particle source unit, attaching a jig to the first charged particle source unit supported by the support member; the jig is gripped to remove the first charged particle source unit from the support member.

13. In claim 12, The jig is An electrode; Wiring electrically connecting the first charged particle source unit and the electrode; Including, A method for replacing a charged particle source unit, wherein in the step of removing the first charged particle source unit, the first charged particle source unit and the electrode are electrically connected by the wiring, and the electrode is brought into contact with the chamber.

14. In claim 11, the support member extends from a sidewall of the chamber toward a center of the chamber; A method for replacing a charged particle source unit, wherein the step of attaching the second charged particle source unit to the support member includes pushing the second charged particle source unit into the support member in a direction opposite to the direction in which the support member extends.

15. In any one of claims 11 to 14, the charged particle beam device includes a housing that houses a column and the chamber; a housing door for accessing the chamber door is provided on a side surface of the housing; The method for replacing a charged particle source unit includes the step of opening the housing door before the step of opening the chamber door.

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