Method for replacing charged particle beam apparatus and 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 apparatus and a method for replacing a charged particle source unit.

Background Art

[0002] In charged particle beam apparatuses such as transmission electron microscopes, scanning electron microscopes, and focused ion beam apparatuses, a charged particle beam is emitted from a charged particle source. Since the charged particle source has a service life, it needs to 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

Summary of Invention

Problem to be Solved by the Invention

[0004] In such a charged particle beam apparatus, it is desired that the charged particle source can be easily replaced.

Means for Solving the Problem

[0005] One aspect of the charged particle beam apparatus 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 inside the chamber; a chamber door provided on the side wall of the chamber for accessing the inside of the chamber; an irradiation optical system for irradiating a sample with an electron beam; an imaging optical system for forming an image with electrons transmitted through the sample; a housing; and including; The charged particle source generates an electron beam, The housing accommodates a lens barrel that houses the irradiation optical system and the imaging optical system, and the chamber, A housing door for accessing the chamber door is provided on a side surface of the housing. One aspect of the charged particle beam apparatus 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 inside the chamber, a chamber door provided on a side wall of the chamber for accessing the inside of the chamber, including the support member extends from the side wall of the chamber toward the center of the chamber, The charged particle source unit ,before the direction in which the support member extends It is configured to be detachably attached to the support member in accordance with the above. .

[0006] In such a charged particle beam apparatus, the charged particle source unit can be taken out from or introduced through the chamber door provided on the side wall of the chamber, so that replacement of the charged particle source unit is easy.

[0007] One aspect of the method for replacing a charged particle source unit 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 inside the chamber, a method for replacing the charged particle source unit in a charged particle beam apparatus, the charged particle beam apparatus comprising a chamber door provided on a side wall of the chamber for accessing the inside of the chamber, the method comprising a step of opening the chamber door, a step of detaching the first charged particle source unit from the support member, The steps include introducing the 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 fruit, In the step of removing the first charged particle source unit, A jig is attached to the first charged particle source unit supported by the support member, The jig is grasped and the first charged particle source unit is removed from the support member. One aspect of the method for replacing a charged particle source unit according to the present invention is: Chamber and A charged particle source unit having a charged particle source, A support member provided on the side wall of the chamber, which detachably supports the charged particle source unit within the chamber, A method for replacing a charged particle source unit in a charged particle beam apparatus, the apparatus comprising a chamber door provided on the side wall of the chamber for accessing the inside of the chamber, The process of opening the chamber door, The steps include removing the first charged particle source unit from the support member, The steps include introducing the 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, The charged particle beam apparatus includes a housing that contains a microscope tube and the chamber, A housing door is provided on the side of the housing for accessing the chamber door. The process includes opening the housing door before opening the chamber door. One aspect of the method for replacing a charged particle source unit according to the present invention is: Chamber and A charged particle source unit having a charged particle source, A support member provided on the side wall of the chamber, which detachably supports the charged particle source unit within the chamber, A method for replacing a charged particle source unit in a charged particle beam apparatus, the apparatus comprising a chamber door provided on the side wall of the chamber for accessing the inside of the chamber, The process of opening the chamber door, The steps include removing the first charged particle source unit from the support member, The steps include introducing the 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, The support member extends from the side wall of the chamber toward the center of the chamber, In the step of attaching the second charged particle source unit to the support member, the second charged particle source unit is pushed into the support member from a direction opposite to the direction in which the support member extends.

[0008] In this method of replacing charged particle source units, the first charged particle source unit is removed from the chamber door located on the side wall of the chamber, and the second charged particle source unit is introduced. Because it can be done in this way, the charged particle source unit can be easily replaced. [Brief explanation of the drawing]

[0009] [Figure 1] A diagram showing an example of the configuration of a transmission electron microscope. [Figure 2] A schematic perspective view showing the enclosure. [Figure 3] A schematic front view of a transmission electron microscope. [Figure 4] A schematic diagram showing the enclosure door in the open position. [Figure 5] A schematic perspective view showing the electron gun chamber. [Figure 6] A schematic perspective view showing the electron gun chamber. [Figure 7] A schematic perspective view showing the electron gun chamber. [Figure 8] A schematic perspective view showing the bottom of the electron gun chamber. [Figure 9] A schematic cross-sectional perspective view showing a filament unit. [Figure 10] A schematic exploded perspective view showing the filament unit. [Figure 11] A schematic perspective view showing how the filament unit is attached to the mounting part of the support section. [Figure 12] A schematic perspective view showing the filament unit attached to the mounting part of the support section. [Figure 13] A schematic perspective view showing the filament unit attached to the mounting part of the support member. [Figure 14] A diagram illustrating the locking mechanism for securing the filament unit to the support member. [Figure 15] A flowchart showing an example of how to replace a filament unit. [Figure 16] A schematic perspective view showing the jig. [Figure 17] A schematic perspective view showing the jig. [Figure 18] A schematic perspective view illustrating the process of removing the first filament unit. [Figure 19] A schematic perspective view illustrating the process of attaching the second filament unit. [Figure 20] A flowchart showing an example of the voltage boosting process in the control unit. [Figure 21] A flowchart showing an example of the start process for the control unit. [Figure 22] A diagram illustrating the power supply circuit for applying acceleration voltage. [Figure 23] A diagram illustrating the power supply circuit in the event of a discharge. [Figure 24] A flowchart illustrating an example of the automatic boosting process in the control unit's start function. [Figure 25] A diagram showing an example of boost-down operation of an accelerating voltage. [Modes for carrying out the invention]

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

[0011] Furthermore, the following description will focus on the case where the charged particle beam apparatus according to the present invention is a transmission electron microscope equipped with a filament as a charged particle source and generates an electron beam from the filament. However, the charged particle beam apparatus according to the present invention may also be an apparatus 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 microscope 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 Figure 1, the transmission electron microscope 2 consists of a housing 100, a main body 200, and a sample holder. -300, control unit 400, and vacuum exhaust system 500 are included.

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

[0015] The main unit 200 includes an electron source 210, an irradiation optical system 220 for irradiating a sample S with electrons emitted from the electron source 210, a holder support unit 230 with an insertion opening for inserting and removing a sample holder 300, an imaging optical system 240 for imaging electrons that have passed through the sample S, an imaging device 250 for capturing a transmission electron microscope image (TEM image) formed by electrons that have passed through the sample S, and a detector 260 for detecting electrons that have passed through the sample S and obtaining 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 illumination optical system 220 and the imaging optical system 240 are housed in the lens barrel 206. The main body 200 is supported by a vibration isolation table 270. The electron gun chamber 202 and the lens barrel 206 are maintained under vacuum by a vacuum evacuation 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 unit 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 sample S to be scanned with the electron probe. In the transmission electron microscope 2, a STEM image can be obtained by scanning the sample S with the electron probe and detecting the electrons that have passed through the sample S with the detector 260. In addition, in the transmission electron microscope 2, the irradiation optical system 220 irradiates the sample S with an electron beam parallel to it, the imaging optical system 240 forms a TEM image with the electrons that have passed through the sample S, and the TEM image can be captured by the imaging device 250.

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

[0020] The sample S is supported within the microscope tube 206 by a sample holder 300. The sample holder 300 is inserted into the opening of the holder support section 230. The sample holder 300 can be inserted into and removed from the opening of the holder support section 230. Therefore, the sample holder 300 is detachable from the holder support section 230.

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

[0022] The vacuum evacuation system 500 evacuates the electron gun chamber 202, the space inside the microscope tube 206, and the space where the imaging device 250 and detector 260 are located. The vacuum evacuation system 500 is controlled by the control unit 400. The computer functioning as the control unit 400 and the vacuum evacuation system 500 may be located outside the housing 100.

[0023] 1.2. Enclosure Figure 2 is a schematic perspective view of the housing 100. As shown in Figure 2, the housing 100 has a rectangular parallelepiped shape. The housing 100 includes multiple sheet metal pieces. The sheet metal pieces are metal plates. The housing 100 covers the main body 200 with multiple sheet metal pieces. Therefore, the main body 200 is not visible from the outside of the housing 100. The housing 100 may also include multiple resin plates, and the main body 200 may be covered with multiple resin plates.

[0024] Figure 3 is a schematic front view of the transmission electron microscope 2.

[0025] As shown in Figures 2 and 3, a recess 110 is formed in the housing 100. The recess 110 is located on the side surface 102 of the housing 100. The side surface 102 is the surface that constitutes the front of the housing 100. A replacement port 120 is formed at the bottom of the recess 110. The replacement port 120 is an opening for the sample holder 300 to access the insertion port of the holder support portion 230.

[0026] Figure 4 schematically shows the housing door 104 of the housing 100 in the open position. The housing door 104 is provided on the side 103 of the housing 100. Opening the housing door 104 provides access to the chamber door 204 provided on the electron gun chamber 202.

[0027] 1.3. Electron gun chamber Figures 5 and 6 are schematic perspective views of the electron gun chamber 202. Figure 5 shows the chamber door 204 in the closed position, while Figure 6 shows the chamber door 204 in the open position.

[0028] As shown in Figures 5 and 6, the chamber door 204 is provided on the side wall of the electron gun chamber 202. The side wall of the electron gun chamber 202 is provided with an exchange port 202a that penetrates the side wall, and the chamber door 204 can hermetically seal the exchange port 202a. An O-ring 203 is fitted to the chamber door 204, and the O-ring 203 can hermetically seal the gap between the chamber door 204 and the side wall of the electron gun chamber 202.

[0029] Figure 7 is a schematic perspective view showing the electron gun chamber 202, the support member 700, and the filament unit 600.

[0030] As shown in Figure 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 is provided with a passage for the electron beam.

[0032] The filament unit 600 is supported within the electron gun chamber 202 by a support member 700. The support member 700 detachably supports the filament unit 600 within 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 202b 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 horizontal, and the optical axis A of the electron source 210 is vertical. 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 considered the first direction, the chamber door 204 is located in the first direction of the support member 700. That is, 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 opening 202a, into 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 within 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 source 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 its central axis is parallel to the extension direction D. The tip of the insulator 720 is provided with a mounting portion 730 for attaching the filament unit 600.

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

[0039] Figure 8 is a schematic perspective view showing the bottom of the electron gun chamber 202.

[0040] A two-stage deflection alignment coil 208 is provided at the base located at the bottom of the electron gun chamber 202. The two-stage deflection alignment coil 208 allows for two-dimensional deflection of the electron beam. The two-stage deflection alignment coil 208 is used to correct the misalignment of the optical axis A of the electron source 210 with respect to the optical axis of the irradiation optical system 220. As shown in Figure 8, the filament unit 600 is provided with pin insertion holes 640 for fixing the filament unit 600 to a jig described later.

[0041] 1.4. Filament Unit Figure 9 is a schematic cross-sectional perspective view of the filament unit 600. Figure 10 is a schematic exploded perspective view of 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 connecting terminal 606a, a connecting terminal 606b, a Wehnelt 608, a fixing ring 610, and an anti-rotation member 620 (an example of an engaging part).

[0043] The electron source 210 is, for example, a tungsten filament. By passing an electric current through the tungsten filament and heating it, thermionic electrons can be emitted. One end of the electron source 210 is connected to a connecting pin, which is inserted into socket 604a. Similarly, the other end of the electron source 210 is connected to a connecting pin, which is inserted into socket 604b.

[0044] The base 602 has sockets 604a and 604b, and connector terminals 606a and 606b fixed to it. Socket 604a and connector terminal 606a are electrically connected. Socket 604b and connector terminal 606b are electrically connected. Therefore, one end of the electron source 210 is electrically connected to connector terminal 606a, and the other end of the electron source 210 is electrically connected to connector terminal 606b.

[0045] A bias voltage is applied to the Wehnert 608. The bias voltage applied to the Wehnert 608 controls the amount of current emitted from the electron source 210. The Wehnert 608 is fixed to the base 602 by a fixing ring 610. Multiple exhaust holes are formed in the Wehnert 608. This allows for efficient exhaust of air around the electron source 210. The multiple exhaust holes are arranged 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] Figure 11 is a schematic perspective view showing the filament unit 600 being attached to the mounting portion 730 of the support member 700. Figure 12 is a schematic perspective view showing the state in which the filament unit 600 has been attached to the mounting portion 730 of the support member 700.

[0048] The mounting portion 730 is provided with guide grooves 732 and 734 that extend in the extending direction D of the support member 700. As shown in Figure 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 extending direction D without rotating it. 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 extending direction D of the support member 700, and the filament unit 600 can be positioned.

[0049] Figure 13 is a schematic perspective view showing the filament unit 600 attached to the mounting portion 730 of the support member 700.

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

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

[0052] The high-voltage power supply and the electron source 210 can be electrically connected by electrically connecting terminal 606a to terminal 722a and terminal 606a to terminal 722b.

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

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

[0055] By pushing the filament unit 600 into the support member 700 from a direction opposite to the extension direction D of the support member 700, the protruding portion 742 is clamped into the clamping portion 630, fixing the filament unit 600 to the support member 700. Furthermore, by applying a force in the extension direction D to the filament unit 600, the protruding portion 742 is released from the clamping portion 630. In this way, the clamping portion 630 and the protruding portion 742 constitute a locking mechanism 740 for mechanically fixing the filament unit 600. The clamping portion 630 and the protruding portion 742 also 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 Figure 14.

[0056] In the above description, we have explained the case where the filament unit 600 is equipped with an electron source 210 and a Wehnert 608, but the other configurations of the filament unit 600 are not particularly limited as long as it has an electron source 210.

[0057] 2. How to replace the filament 2.1. Procedure for replacing the filament unit Figure 15 is a flowchart showing an example of a method for replacing a filament unit. As shown in Figure 15, the method for replacing a filament unit includes the steps of: S10 opening the housing door 104 of the housing 100; S20 opening the chamber door 204; S30 removing the first filament unit (an example of a first charged particle source unit) from the support member 700; S40 introducing the 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; S50 closing the chamber door 204; and S60 closing the housing door 104 of the housing 100.

[0058] 2.2. Process S10: Opening the enclosure door First, as shown in Figure 4, the housing door 104 of the housing 100 is opened. This allows access to the chamber door 204.

[0059] 2.3. Step S20: Opening the chamber door Next, as shown in Figure 6, the chamber door 204 is opened. This allows access to the electron gun chamber 202. Here, the housing door 104 is located on the side 103 of the housing 100. The chamber door 204 is located on the side wall of the electron gun chamber 202. Therefore, the filament unit 600 can be replaced without performing work at height using a ladder or similar equipment.

[0060] For example, even with a transmission electron microscope that is about 1.8m tall, by installing the chamber door 204 on the side wall of the electron gun chamber 202, the position of the chamber door 204 can be raised to a height of about 1.6m. This allows even a worker who is about 1.5m tall to replace the filament unit 600 using a step stool of about 0.2m. Therefore, with the transmission electron microscope 2, working at heights is unnecessary, and the filament unit 600 can be replaced safely.

[0061] Before step S20, which involves opening the chamber door 204, the inside of the electron gun chamber 202 and the lens barrel 206 are brought to atmospheric pressure.

[0062] 2.4. Step S30: Removing the first filament unit from the support member. Figures 16 and 17 are schematic perspective views of the jig 800. Figure 18 is a schematic perspective view of step S30, in which the first filament unit 600A is removed. Here, the first filament unit 600A is the used filament unit 600.

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

[0064] As shown in Figures 16, 17, and 18, the jig 800 includes a unit base 810, a fixing mechanism 820 for fixing 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 formed therein. The notch 812 is shaped to accommodate the first filament unit 600A. The first filament unit 600A, fitted into the notch 812, is fixed in place by the 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. Inside the pin 822 is a shaft that moves within the pin 822 by the operation of the switching knob 830.

[0067] The pin insertion hole 640 has a smaller diameter section and a larger diameter section with a larger diameter than the smaller diameter section. The smaller diameter section is formed closer to the entrance of the pin insertion hole 640 than the larger diameter section.

[0068] The toggle knob 830 is used to switch between enabling and disabling the fixing of the first filament unit 600A. By rotating the toggle knob 830, the state of enabling and disabling the fixing can be switched. The toggle knob 830 is connected to pin 822.

[0069] When the switch knob 830 is rotated to activate the locking mechanism, the multiple balls fixed to the tip of the pin 822 are pushed outwards by the shaft, and the multiple balls catch on the step between the smaller and larger diameter sections of the pin insertion hole 640. This allows the first filament unit 600A to be fixed to the unit base 810.

[0070] When the toggle knob 830 is rotated to disable the locking mechanism, multiple balls enter the pin 822, which can then pass through the smaller diameter section of the pin insertion hole 640. This releases the locking mechanism of the first filament unit 600A.

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

[0072] As shown in Figure 18, the ground electrode 840 is electrically connected to the first filament unit 600A, which is 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 transmission spring 850 and the pin 822 enable the electrical connection between the ground electrode 840 and the first filament unit 600A. The transmission spring 850 and the pin 822 function as wiring for the electrical connection between the first filament unit 600A and the ground electrode 840.

[0073] In step S30, which involves 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 fixing is enabled using the switch 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 to the extending direction D of the support member 700, thereby pulling the first filament unit 600A out of the support member 700. This allows the first filament unit 600A to be removed from the support member 700. At this time, the connecting terminal 606a is detached from terminal 722a, and the connecting terminal 606b is detached from terminal 722b.

[0075] The first filament unit 600A, with the jig 800 attached, is removed from the electron gun chamber 202 through the replacement port 202a. Here, as shown in Figure 18, the ground electrode 840 is brought into contact with the electron gun chamber 202 as the jig 800 passes through the replacement port 202a. This allows the charge accumulated in the first filament unit 600A to flow to the ground. Since the ground electrode 840 is located at the bottom of the unit stand 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: Attaching the second filament unit to the support member. Figure 19 is a schematic perspective view showing step S30, in which the second filament unit 600B is installed. Here, the second filament unit 600B is a new filament unit 600 that has not been used. Note that the second filament unit 600B may be the first filament unit 600A in which the filament has been replaced with a new filament.

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

[0078] Next, as shown in Figure 11, the protrusion 622 is fitted into the guide groove 732 of the support member 700, and 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 is guided by the guide grooves 732 and 734 and moves to the center of the electron gun chamber 202.

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

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

[0081] 2.6. Step S50 to close the chamber door Next, the chamber door 204 is closed as shown in Figure 5.

[0082] 2.7. Process S60 to close the enclosure door Next, close the housing door 104 as shown in Figure 2.

[0083] By following the above steps, the filament unit 600 can be replaced.

[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 the side wall of the electron gun chamber 202 for detachably supporting the filament unit 600 inside 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, the transmission electron microscope 2 allows the filament unit 600 to 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 compared to, for example, lifting up the electron gun chamber 202 to replace the filament unit 600.

[0085] For example, when lifting the electron gun chamber 202 to replace the filament unit 600, it was necessary to access the top of the transmission electron microscope, requiring work at height. In contrast, with the transmission electron microscope 2, the chamber door 204 is located on the side wall of the electron gun chamber 202, allowing for safe replacement of the filament unit 600 without the need for work at height using a ladder or similar equipment.

[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 a 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 it is possible to prevent excessive force 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. Therefore, the possibility of damage to the support member 700 can be reduced. For example, if the direction in which the support member 700 extends 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 causing damage to the support member 700.

[0087] In the transmission electron microscope 2, the support member 700 has guide grooves 732 and 734 extending in the extending 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 extending direction D of the support member 700. Thus, the possibility of damage to the support member 700 can be reduced.

[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 is possible to do so.

[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 has a second terminal (connection terminals 606a and 606b) electrically connected to the electron source 210. When the filament unit 600 is attached to the support member 700, the first and second terminals are electrically connected. Specifically, when the filament unit 600 is attached to the support member 700, terminal 722a and connection terminal 606a are electrically connected, and terminal 722b and connection terminal 606b are electrically connected. Therefore, in the transmission electron microscope 2, the electron source 210 and the high-voltage power supply can be electrically connected by attaching the filament unit 600 to the support member 700.

[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 that have passed through the sample S. As a result, the microscope tube 206 is tall in the transmission electron microscope 2, but since the chamber door 204 is provided on the side wall of the electron gun chamber 202, the filament unit 600 can be safely replaced without having to perform work at 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 microscope tube 206. A housing door 104 is provided on the side 103 of the housing 100 to provide access to the chamber door 204. Thus, in the transmission electron microscope 2, since the housing door 104 is provided on the side 103 of the housing 100, the chamber door 204, which is 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 from 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 for easy replacement of the filament unit 600 because the first filament unit 600A can be removed from the chamber door 204 and the second filament unit 600B can be introduced.

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

[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 which is supported by the support member 700, and the jig 800 is grasped to remove the first filament unit 600A from the support member 700. Therefore, the first filament unit 600A can be removed without the operator 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 an operator 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 sufficiently. In contrast, with the above method for replacing the filament unit 600, the first filament unit 600A can be removed from the support member 700 without the operator touching the first filament unit 600A, so even immediately after use, the operator can The first filament unit 600A can 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 to electrically connect the first filament unit 600A mounted on 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 electric shock to the worker.

[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. Furthermore, 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. Therefore, the possibility of damage to the support member 700 can be reduced.

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

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

[0100] The control unit 400 performs a conditioning process during the boosting process. The conditioning process involves boosting the voltage to a conditioning voltage value, which is higher than the acceleration voltage to be used, and maintaining this voltage for a certain period of time. After the conditioning process, the boosting process reduces the voltage from the conditioning voltage value to the target acceleration voltage value. Performing the conditioning process reduces the risk of discharge during use.

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

[0102] The control unit 400 first determines whether the user has given an instruction to start automatic voltage boosting (step S100). The control unit 400 determines that the user has given an instruction to start automatic voltage boosting if the user has pressed the automatic voltage boosting start button on the GUI (Graphical User Interface).

[0103] When the control unit 400 determines that the user has given an instruction to start automatic voltage boosting (Yes in S100), it determines whether or not high voltage is being applied (S102). This is to ensure that the voltage boosting process is always started under the same conditions, that is, always without high voltage being applied. By performing the voltage boosting process under consistent conditions, the trends of the device can be understood from the data acquired during the voltage boosting process.

[0104] If the control unit 400 determines that 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 no high voltage is applied (No. in step S102), it determines whether the high voltage is in a conditioning mode (C mode) that allows a conditioning voltage value HTc (step S104). The conditioning voltage value HTc is an acceleration voltage higher than the target acceleration voltage value. After applying the conditioning voltage value HTc, the voltage is reduced to the target acceleration voltage value, thereby reducing the discharge risk when using the target acceleration voltage value. Under normal use, the device is not in conditioning mode, so if it is in conditioning mode, it is determined to be abnormal.

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

[0107] If the control unit 400 determines that the device is not in conditioning mode (No. in step S104), it starts the conditioning process.

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

[0109] If the control unit 400 determines that no cancellation instruction has been given (No. in step S110), it measures the vacuum level in the electron gun chamber 202 (step S112). The control unit 400 obtains the measured value of the vacuum level in the electron gun chamber 202 from a vacuum gauge used to measure the vacuum level in the electron gun chamber 202.

[0110] The control unit 400 stores the measured values ​​obtained from the vacuum gauge in the memory unit. If the memory unit does not contain information on the achievable vacuum level, the control unit 400 records the measured value as the achievable vacuum level in the memory unit. If the memory unit contains information on the achievable vacuum level, the control unit 400 compares the stored achievable vacuum level with the measured value, and updates the achievable vacuum level if the measured value is higher than the stored achievable vacuum level.

[0111] Next, the control unit 400 determines the number of times the high voltage application is turned on N HT However, the set number of times N A Determine whether it exceeds (step S114). Number of times the high voltage was turned on N HT This corresponds to the number of times the high voltage application has been turned off. The number of times the high voltage application has been turned off corresponds to the set number N. A If the reading exceeds this limit, there is a high probability that there is a problem with the high-voltage power supply or other components.

[0112] The control unit 400 determines the number of times high voltage is applied N HT The number of times N is set AIf it is determined that the value does not exceed (No. in step S114), it is determined whether or not high voltage application is turned on (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 vacuum level in the electron gun chamber 202 is above a threshold (step S118). If the measured value stored in the memory unit is above the threshold (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 process in step S108.

[0114] On the other hand, if the control unit 400 determines that the measured value stored in the memory unit is not above a threshold (No. in step S118), it waits for a certain period of time to improve the vacuum level, and then proceeds to step S Return to processing step 108.

[0115] If the control unit 400 determines that high voltage is being applied (Yes in step S116), it determines whether 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 obtains a measured value of the vacuum level in the electron gun chamber 202 from the vacuum gauge. The control unit 400 compares the measured value with the target vacuum level stored in the memory unit and determines that the vacuum has deteriorated if the measured value is lower than the target vacuum level and the difference between the measured value and the target vacuum level is greater than or equal to a predetermined value. If the measured value and the target vacuum level do not satisfy this relationship, the control unit 400 determines that the vacuum level has not deteriorated.

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

[0118] If the control unit 400 determines that the vacuum has not deteriorated (No. in step S124), it determines whether the high voltage has reached the conditioning voltage value HTc (step S126). If the control unit 400 determines that the high voltage has not reached the conditioning voltage value HTc (No. in step S126), it raises the high voltage by a predetermined fixed value (step S127). Then, the control unit 400 returns to the process in 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. Note that the predetermined time can be set to any time.

[0120] If the control unit 400 determines that a predetermined time has not elapsed since the high voltage reached the conditioning voltage value HTc (No. in step S128), it returns to the process 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), determines that an error has occurred in the device (Yes in step S108), determines that a cancellation instruction has been given (Yes in step S110), or determines the number of times the high voltage has been turned on N HT However, the set number of times N A If it is determined that the value has exceeded the limit (Yes in step S114), the conditioning process is terminated.

[0122] After completing the conditioning process, the control unit 400 determines whether an apparatus error or process cancellation has occurred (step S130). When the control unit 400 determines that an error has occurred in the apparatus (Yes in step S108), determines that a cancellation instruction has been issued (Yes in step S110), or the number N of times high voltage application is turned on HT exceeds the set number of times N A (Yes in step S114), it determines that an apparatus error or process cancellation has occurred (No in step S130), turns off the high voltage (step S134), and terminates the boosting process.

[0123] When the control unit 400 determines that a predetermined time has elapsed after the high voltage reaches the conditioning voltage value HTc (Yes in step S128), it determines that there is no apparatus error or process cancellation (No in step S130), steps down the voltage to the target acceleration voltage value (step S132). Thereby, the acceleration voltage can be set to the target acceleration voltage value. After stepping down the voltage to the target acceleration voltage value, the control unit 400 terminates the boosting process.

[0124] 4.3. Start Function When the acceleration voltage to be used is not the maximum acceleration voltage, or when the time during which the inside of the electron gun chamber 202 and the inside of the lens barrel 206 are exposed to the atmosphere is short at the time of replacing the filament unit 600, the risk of discharge is low. In this case, the start function may be used without performing the above-described conditioning process. The start function is a function that optimizes the states of the acceleration voltage, the filament, and the optical system to the conditions set by the user, and immediately brings the apparatus into a state ready for observation.

[0125] The boost function in the starter is intended for everyday use by the user and is not suitable for degassing from the electron gun chamber 202 or filament unit 600, or when there is debris or other adhering material. If there is a risk of discharge, use the conditioning function described above. The transmission electron microscope 2 has two automatic boost methods depending on the state of the device, which minimizes downtime and allows the user to avoid being tied to the device.

[0126] 4.4. Startup Process Figure 21 is a flowchart showing an example of the start process of the control unit 400.

[0127] The control unit 400 first determines whether the user has given an instruction to start the start process (step S200). The control unit 400 determines that the user has given an instruction to start the start process if the user has pressed the start process button on the GUI.

[0128] Before starting the 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 the pull-down menu on the GUI screen.

[0129] If the control unit 400 determines that the user has given 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. Also, if the image field is not "Bright", it sets it to "Bright". If "IOS off" is on, it turns it off. In addition, it turns off all Wobblers.

[0130] By initializing these items, observations can always be started in the same state, even if the previous user ended with different settings.

[0131] Next, the control unit 400 checks for abnormalities in the device (step S202). If the control unit 400 determines that there is an abnormality in the device and that the abnormality cannot be resolved by resetting the device, it determines that there is an abnormality in the device (Yes in step S202) and terminates 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 abnormalities in the device again.

[0132] If the control unit 400 determines that there is no abnormality in the device (No. in step S202), the vacuum level inside the electron gun chamber 202 and the lens barrel 206 is at a level where it is safe to start the pressure increase. The control unit 400 determines whether the vacuum level has reached a level where it is safe to start increasing the pressure. If the vacuum level has not reached a level where it is safe to start increasing the pressure, the control unit 400 sets a waiting period of a certain amount of time, and then determines again whether the vacuum level has reached a level where it is safe to start increasing the pressure. If the vacuum level has not reached a level where it is safe to start increasing the pressure even after the waiting period of a certain amount of time, the control unit 400 determines that there is a problem with the device (Yes in step S206) and terminates the start process.

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

[0134] In order to use the transmission electron microscope 2, it is necessary to pass an electric current through the electron lens. However, when the transmission electron microscope 2 is not in use, it is desirable to stop the current from flowing through the electron lens. Maintaining the current through the electron lens consumes a large amount of power, resulting in a high environmental burden. Therefore, in the transmission electron microscope 2, the current from the electron lens is stopped when it is not in use, and in this process S208, the current is started to flow through the electron lens. If the control unit 400 finds that a predetermined current is not flowing through the electron lens, it determines that there is a problem with the device (Yes in step S210) and terminates the start process.

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

[0136] Here, the target acceleration voltage value is set using the pull-down menu on the GUI screen. The control unit 400 increases the acceleration voltage so that it reaches the set target acceleration voltage value. The boosting function using the start function has a mechanism to adjust the acceleration voltage while boosting it in order to prevent discharge. This mechanism will be explained later in "4.5. Boosting Process S212".

[0137] If the control unit 400 fails to raise the acceleration voltage to the target acceleration voltage value, it determines that there is an abnormality in the high-voltage system (Yes in step S214) and terminates the start process.

[0138] When 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 generates an electron beam in the electron source 210 (step S216).

[0139] The control unit 400 first determines whether the sample holder 300 is inserted into the holder support unit 230. If the sample holder 300 is not inserted, the control unit 400 decides not to perform microscopic examination immediately and skips processes S216 and S218. In this case, no power is supplied to the filament.

[0140] If the control unit 400 determines that the sample holder 300 is inserted, it starts supplying power to the electron source 210, i.e., to the filament. At this time, if the control unit 400 determines that no current flows to the filament despite the power being supplied, it determines that the filament is broken (Yes in step S218) and terminates the start process.

[0141] The control unit 400, when it determines that current is flowing through the filament, applies high voltage to start emitting the 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 after a predetermined time has elapsed, the control unit 400 will not proceed. If not, the system determines that there is a malfunction in the device (Yes in step S218) and terminates the start process.

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

[0143] The control unit 400 inserts a detector according to the usage mode set by the user on the GUI screen in advance. First, the control unit 400 determines whether or not the sample holder 300 is inserted into the holder support unit 230. If the sample holder 300 is not inserted, the control unit 400 decides not to perform microscopic examination immediately and skips process 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 operating mode. For example, although not shown in the diagram, if the TEM mode is set, the scan detector is ejected off the optical axis and the fluorescent screen is inserted on the optical axis. Also, although not shown in the diagram, if the mode for measurement using EDS is set, the EDS detector is inserted.

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

[0146] The control unit 400 controls the illumination 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 initializes the function that maintains a constant brightness on the sample surface regardless of the magnification (brightness magnification link function). This allows the user to start using the system under the same conditions as the previous session, regardless of the conditions under which the session ended.

[0147] First, the control unit 400 determines whether the sample holder 300 is inserted into the holder support unit 230. If the sample holder 300 is not inserted, the control unit 400 decides not to perform microscopic examination immediately and skips process S222. If the control unit 400 determines that the sample holder 300 is inserted, it changes to the imaging mode according to the set optical conditions. Next, the control unit 400 initializes the brightness magnification link function. The initialization of the brightness magnification link function will be described later. Next, the deflector system is set to the default value and changed to the set observation magnification. Through the above processes, the optical conditions can be set.

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

[0149] Next, the control unit 400 checks for abnormalities in the device (step S224). If the control unit 400 determines that there is an abnormality in the device and that the abnormality cannot be resolved by resetting the device, it determines that there is an abnormality in the device (Yes in step S224) and terminates 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 abnormalities in the device again.

[0150] If 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 of the entire field of view of the sample S. The control unit 400 displays the acquired map image on the GUI screen. This map The image displays the user's current location, allowing them to understand which area they are observing. Furthermore, the map image helps identify points of interest to focus on.

[0151] The control unit 400 first determines whether the sample holder 300 is inserted into the holder support unit 230. If the sample holder 300 is not inserted, the control unit 400 decides not to perform microscopic examination immediately and skips process S226.

[0152] The control unit 400 determines whether a map image has already been acquired, and if a map image has already been acquired, it skips process S226. Next, the control unit 400 opens the beam shutter and sets the magnification to the lowest magnification. Next, the control unit 400 changes the spot size (size of the electron beam). Next, the control unit 400 adjusts the brightness by changing the excitation value of the condenser lens. Next, the control unit 400 ejects all apertures from the optical axis. Next, the control unit 400 adjusts the position of the sample S and takes a map image with the imaging device 250. After taking the map image, the control unit 400 returns the optical system conditions to the state before process S226 was performed. Finally, the control unit 400 closes the beam shutter. Through the above processes, a map image can be acquired. After acquiring the map image, the control unit 400 ends the start process.

[0153] 4.5. Boosting process S212 Figure 22 shows the acceleration voltage V ACC This is a diagram illustrating the power supply circuit 900 for applying the power. As shown in Figure 22, the power supply circuit 900 includes a high-voltage generation circuit 910 (high-voltage power supply), a load current detection circuit 920, and a filter circuit 930.

[0154] To generate high voltage, a small load current I L It is necessary to flow load current I L The current flows through a filter circuit 930 that removes high-frequency noise and a high-voltage generation circuit 910, and the load current I is detected by the load current detection circuit 920. L It is monitoring the current value.

[0155] Figure 23 is a diagram illustrating the power supply circuit 900 when a discharge occurs. If a discharge occurs during voltage boosting, the discharge current I from the electron gun section... D Load current I L The load current I is superimposed and flows into the load current detection circuit 920. L Since there is a theoretical value corresponding to the acceleration voltage value, the load current I after boosting to a constant value L By comparing the actual current value with the theoretical value, it is possible to detect an increase in current due to a small discharge. This allows for voltage boosting while avoiding discharge.

[0156] Figure 24 is a flowchart showing an example of the boost processing S212 of the control unit 400.

[0157] When the control unit 400 starts the boost processing S212, it first checks the load current I measured by the load current detection circuit 920. L The measured value of is obtained (S300). The control unit 400 controls the load current I L Determine whether the measured value is lower than the blood pressure reduction criterion (S302).

[0158] The control unit 400 controls the load current I L If the measured value is above the blood pressure reduction criterion, i.e., I L<If the step-down criterion is not met (No. in step S302), discharge is assumed to be occurring, and the accelerating voltage V ACC The control unit 400 lowers the acceleration voltage V by the default value (S304). ACC After lowering it by the default value (after step S304), return to step S300.

[0159] The control unit 400 controls the load current I L If the measured value is lower than the blood pressure reduction criterion, i.e., I L If the blood pressure reduction criterion is met (Yes in step S302), determine whether the measured value is lower than the maintenance criterion (S306).

[0160] The control unit 400 controls the load current I L If the measured value is above the maintenance standard, i.e., I L <maintain If the criteria are not met (No. in step S306), discharge is assumed to be occurring, and the accelerating voltage V ACC Maintain the specified time (S308). The control unit 400 controls the acceleration voltage V ACC After maintaining this 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 is smaller than the maintenance standard, i.e., I L <If the maintenance criteria are met (Yes in step S306), the acceleration voltage V ACC The voltage is increased by a predetermined amount (step S310). In this way, the control unit 400 controls the load current I L If the measured value is lower than the step-down criterion and also lower than the maintenance criterion, the acceleration voltage V ACC The voltage is increased by the default value. Note that the maintenance threshold value is smaller than the reduction threshold value. The reduction threshold value and the maintenance threshold value can be set to any value.

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

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

[0164] The control unit 400 controls the load current I L Before the measurement process S300, the device may be checked for abnormalities. If the control unit 400 determines that there is an abnormality in the device (Yes in step S214), it will terminate the start process. Also, if the control unit 400 fails 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. Also, if the control unit 400 fails 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] Figure 25 shows an example of the step-up / step-down operation of the accelerating voltage. Load current I L If the measured value falls within the standard range, i.e., the load current I L If the measured value is smaller than the maintenance standard, the load current I L The measurement and the boosting of the acceleration voltage by a predetermined value are repeated. Due to the discharge, a sudden load current I L When an increase occurs, the load current I L This deviates from the theoretical value. In the example shown in Figure 25, the load current I L Because the measured value exceeds the step-down criterion, the acceleration voltage V ACC Performs a step-down operation. Acceleration voltage V ACC After the step-down operation is performed, the load current I L Measure the load current I LIf the measured value is smaller than the maintenance standard, the acceleration voltage V ACC Restart the voltage boosting process.

[0166] 4.6. Effects In the transmission electron microscope 2, when replacing the filament unit 600, the inside of the electron gun chamber 202 and the microscope tube 206 are exposed to the atmosphere, making discharge likely when applying the acceleration voltage. Conventionally, in order to safely increase the acceleration voltage, it was necessary for an operator to carefully apply high voltage and perform aging after the vacuum level inside the microscope tube 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] As shown in Figure 20, the transmission electron microscope 2 allows for automatic aging, making it easy to increase the acceleration voltage without requiring an operator to be tied to the device. Furthermore, if aging is not required, the transmission electron microscope 2 can increase the acceleration voltage using its start function.

[0168] 5. Variations It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be implemented within the scope of the gist of the present invention.

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

[0170] Furthermore, the charged particle beam apparatus according to the present invention is not limited to a transmission electron microscope, but may also be a scanning electron microscope or a focused ion beam apparatus. That is, the charged particle beam apparatus according to the present invention comprises a charged particle source unit having a charged particle source that generates charged particle beams such as electron beams and ion beams.

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

[0172] 2…Transmission electron microscope, 100…Housing, 102…Side, 103…Side, 104…Housing 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…Microscope tube, 208…Alignment coil, 210…Electron source, 220…Irradiation optics, 230…Holder support, 240…Imaging optics, 250…Imaging device, 260…Detector, 270…Vibration isolation table, 300…Sample holder, 400…Control unit, 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…Anti-rotation member, 622…Protrusion, 624…Protrusion, 630…Clamping part, 640…Pin insertion hole, 700…Support member, 710…Pipe, 720…Insulator, 722a…Terminal, 722b…Terminal, 730…Mounting part, 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. Chamber and A charged particle source unit having a charged particle source, A support member provided on the side wall of the chamber, which detachably supports the charged particle source unit within the chamber, A chamber door is provided on the side wall of the chamber for accessing the inside of the chamber, An irradiation optical system for irradiating a sample with an electron beam, An imaging optical system for forming an image with electrons transmitted through the aforementioned sample, The casing and Includes, The charged particle source generates an electron beam, The housing contains a lens barrel that houses the illumination optical system and the imaging optical system, and the chamber. A charged particle beam apparatus, wherein a housing door for accessing the chamber door is provided on the side of the housing.

2. In claim 1, The support member extends from the side wall of the chamber toward the center of the chamber, The charged particle source unit is configured to be detachably attached to the support member along the direction in which the support member extends, in a charged particle beam apparatus.

3. Chamber and A charged particle source unit having a charged particle source, A support member provided on the side wall of the chamber, which detachably supports the charged particle source unit within the chamber, A chamber door is provided on the side wall of the chamber for accessing the inside of the chamber, Includes, The support member extends from the side wall of the chamber toward the center of the chamber, The charged particle source unit is configured to be detachably attached to the support member along the direction in which the support member extends, in a charged particle beam apparatus.

4. In any one of claims 1 to 3, The support member extends from the side wall of the chamber toward the center of the chamber, The support member has a guide that extends in the direction in which the support member extends, The charged particle source unit has an engaging portion that engages with the guide, wherein the charged particle beam apparatus is a charged particle beam apparatus.

5. In any one of claims 1 to 3, The support member extends from the side wall of the chamber in a first direction, The chamber door is located in the first direction relative to the support member in the charged particle beam apparatus.

6. In claim 2 or 3, A charged particle beam apparatus in which the optical axis of the charged particle source is perpendicular to the direction in which the support member extends.

7. In any one of claims 1 to 3, The support member includes an insulator, The insulator holds a first terminal electrically connected to the power supply, The charged particle source unit has a second terminal electrically connected to the charged particle source, A charged particle beam apparatus in which the charged particle source unit is attached to the support member, thereby electrically connecting the first terminal and the second terminal.

8. In claim 3, A charged particle beam apparatus including an optical system for irradiating a sample with a charged particle beam emitted from the charged particle source.

9. In claim 3, The charged particle source is a charged particle beam device that generates an electron beam.

10. In claim 9, An irradiation optical system for irradiating a sample with an electron beam, An imaging optical system for forming an image with electrons transmitted through the aforementioned sample, A charged particle beam device, including one.

11. In claim 10, Including the casing, The housing contains a lens barrel that houses the illumination optical system and the imaging optical system, and the chamber. A charged particle beam apparatus, wherein a housing door for accessing the chamber door is provided on the side of the housing.

12. Chamber and A charged particle source unit having a charged particle source, A support member provided on the side wall of the chamber, which detachably supports the charged particle source unit within the chamber, A method for replacing a charged particle source unit in a charged particle beam apparatus, the apparatus comprising a chamber door provided on the side wall of the chamber for accessing the inside of the chamber, The process of opening the chamber door, The steps include removing the first charged particle source unit from the support member, The steps include introducing the 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, In the step of removing the first charged particle source unit, A jig is attached to the first charged particle source unit supported by the support member, A method for replacing a charged particle source unit, comprising gripping the jig and removing the first charged particle source unit from the support member.

13. In claim 12, The aforementioned jig is Electrodes and, Wiring that electrically connects the first charged particle source unit and the electrode, Includes, A method for replacing a charged particle source unit, comprising the step of removing the first charged particle source unit, wherein 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. Chamber and A charged particle source unit having a charged particle source, A support member provided on the side wall of the chamber, which detachably supports the charged particle source unit within the chamber, A method for replacing a charged particle source unit in a charged particle beam apparatus, the apparatus comprising a chamber door provided on the side wall of the chamber for accessing the inside of the chamber, The process of opening the chamber door, The steps include removing the first charged particle source unit from the support member, The steps include introducing the 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, The charged particle beam apparatus includes a housing that contains a microscope tube and the chamber, A housing door is provided on the side of the housing for accessing the chamber door. A method for replacing a charged particle source unit, comprising the step of opening the housing door before the step of opening the chamber door.

15. In any one of claims 12 to 14, The support member extends from the side wall of the chamber toward the center of the chamber, A method for replacing a charged particle source unit, wherein in the step of attaching the second charged particle source unit to the support member, the second charged particle source unit is pushed into the support member from a direction opposite to the direction in which the support member extends.

16. In claim 12 or 13, The charged particle beam apparatus includes a housing that contains a microscope tube and the chamber, A housing door is provided on the side of the housing for accessing the chamber door. A method for replacing a charged particle source unit, comprising the step of opening the housing door before the step of opening the chamber door.

17. Chamber and A charged particle source unit having a charged particle source, The charged particle source unit is provided on the side wall of the chamber and within the chamber A support member that detachably supports the and A method for replacing a charged particle source unit in a charged particle beam apparatus, the apparatus comprising a chamber door provided on the side wall of the chamber for accessing the inside of the chamber, The process of opening the chamber door, The steps include removing the first charged particle source unit from the support member, The steps include introducing the 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, The support member extends from the side wall of the chamber toward the center of the chamber, A method for replacing a charged particle source unit, wherein in the step of attaching the second charged particle source unit to the support member, the second charged particle source unit is pushed into the support member from a direction opposite to the direction in which the support member extends.

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