JP7114426B2 - Charged particle beam device - Google Patents

Description

The present invention relates to a charged particle beam device.

In charged particle beam instruments such as electron microscopes, a fixing member (for example, a cartridge) that holds a cooled sample is placed in the sample chamber in order to prevent the structure of the sample from being destroyed, making it impossible to observe the sample in a normal state. In some cases, the sample is observed while being held by a provided holding portion.

However, when the sample is cooled, the cartridge and the holder that holds the cartridge may shrink, creating a gap between these members. If there is a gap, the sample to be observed vibrates, which may cause noise in the observed image.

Patent Document 1 discloses a technique for suppressing thermal expansion/contraction of a member by detecting the ambient temperature of a sample and appropriately controlling the temperature with a temperature control means.

U.S. Pat. No. 7,238,953

However, the technique disclosed in Patent Document 1 requires precise control of the ambient temperature of the sample, and has the problem of complicating the structure and control of the apparatus.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a charged particle beam apparatus capable of easily suppressing the occurrence of noise in an image to be observed.

In order to solve the above problems and achieve the object of the present invention, the present invention provides a charged particle beam device configured as follows.

a sample holding mechanism (for example, a sample holding mechanism 160 described later) that holds a sample fixing member to which the sample is fixed in the sample chamber;
A charged particle beam device comprising a control unit (for example, a control board 300 described later) that controls the sample holding mechanism,
The sample holding mechanism is
a mounting portion (for example, a mounting portion 242 to be described later) on which the sample fixing member is mounted;
a locking portion (for example, a locking portion 243 to be described later) that moves from a predetermined initial position and locks the sample fixing member placed on the mounting portion;
a temperature detection unit (for example, a temperature detection mechanism 245 described later) that detects the temperature in the sample chamber,
the locking portion moves in a direction to press the sample fixing member against the mounting portion when locking the sample fixing member;
A charged particle beam apparatus, wherein the control unit determines the amount of movement of the locking unit according to the temperature in the sample chamber detected by the temperature detection unit.

According to the present invention, it is possible to easily suppress the occurrence of noise in an observed image.
Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

It is a figure showing an example of composition of a charged particle beam device concerning this embodiment. It is a figure which shows an example of the principal part of the charged particle beam apparatus which concerns on this embodiment. It is a figure which shows typically the cartridge of the charged particle beam apparatus which concerns on this embodiment. It is a figure which shows an example of the sample holding|maintenance part of the charged particle beam apparatus which concerns on this embodiment. It is a functional block diagram showing the circuit configuration of the charged particle beam device according to the present embodiment. It is a figure (1) for demonstrating the outline|summary of operation|movement of the charged particle beam apparatus which concerns on this embodiment. It is a figure (2) for demonstrating the outline|summary of operation|movement of the charged particle beam apparatus which concerns on this embodiment. 3 is a diagram (part 3) for explaining an overview of the operation of the charged particle beam device according to the present embodiment; FIG. FIG. 4 is a diagram (part 4) for explaining the outline of the operation of the charged particle beam device according to the present embodiment; It is a figure (1) for demonstrating operation|movement of the sample holding|maintenance part of the charged particle beam apparatus which concerns on this embodiment. FIG. 11 is a diagram (part 2) for explaining the operation of the sample holder of the charged particle beam device according to the present embodiment;

Preferred embodiments of the present invention will be described in detail below with reference to the drawings. It should be noted that the embodiments described below do not unduly limit the scope of the invention described in the claims. Moreover, not all the configurations described below are essential constituent elements of the present invention.

1. Overview of Charged Particle Beam Device First, an overview of a charged particle beam device according to this embodiment will be described with reference to the drawings. FIG. 1 is a diagram showing an example of the configuration of a charged particle beam device 100 according to this embodiment.

As shown in FIG. 1, the charged particle beam device 100 in this embodiment is a transmission electron microscope (TEM), and includes a sample chamber 20, a sample exchange device 100A, a charged particle beam source 110, an optical system 120, It is configured including an imaging device 130 and a sample holding mechanism 160 .

The sample chamber 20 is the space within the barrel 22 as shown in FIG. The sample chamber 20 is a space defined by the inner wall of the barrel 22 . That is, the lens barrel 22 can also be said to be a vacuum vessel having the sample chamber 20 .

The inside of the sample chamber 20 is evacuated by an evacuation device (not shown). Thereby, the sample chamber 20 is kept in a vacuum. Here, vacuum refers to a spatial state in which the pressure is lower than the atmospheric pressure. Further, evacuation refers to evacuating the internal gas in order to obtain a desired vacuum state. As an evacuation device for evacuating the sample chamber 20, for example, an ion pump, a scroll pump, a turbomolecular pump, or the like can be used.

A sample holding mechanism 160 is attached to the barrel 22 . The sample holding mechanism 160 includes a sample holding section 24 , a sample holder 26 , a goniometer 28 and a motor 29 .

A goniometer 28 is attached to the outer wall of the barrel 22 . A sample holder 26 is provided so as to pass through the lens barrel 22 . One end of the sample holder 26 is arranged outside the barrel 22 and connected to the goniometer 28 . The other end of the sample holder 26 is arranged inside the sample chamber 20 and connected to the sample holder 24 .

The sample holding unit 24 holds the cartridge (retainer) 2 conveyed from the sample exchange apparatus 100A and to which the sample S is fixed. A goniometer 28 is used to position the sample S held by the sample holder 24 in the sample chamber 20 .

The motor 29 is provided outside the lens barrel 22, and constitutes a driving source for driving a locking portion 243 of the sample holding portion 24, which will be described later. In this embodiment, the motor 29 is a stepping motor (pulse motor). The details of the sample holder 24 and the details of the sample exchange device 100A will be described later.

The sample chamber 20 is a space in which the sample S is irradiated with a charged particle beam (electron beam). In the charged particle beam device 100 , the sample S held by the sample holder 24 is irradiated with an electron beam in the sample chamber 20 . The electron beam transmitted through the sample S is imaged by an optical system to obtain an electron microscope image.

A charged particle beam source 110 is attached to the upper portion of the lens barrel 22 and generates an electron beam (charged particle beam) EB. For example, a known electron gun can be used as the charged particle beam source 110 . The electron gun used as the charged particle beam source 110 is not particularly limited, and for example, a thermionic emission type, a thermal field emission type, a cold cathode field emission type, or the like can be used.

The optical system 120 includes an irradiation lens 122 for irradiating the sample S with the electron beam EB, an objective lens 124 and an intermediate lens 126 forming an imaging system for forming an image with the electron beam EB that has passed through the sample S. , and a projection lens 128 .

The imaging device 130 captures an electron microscope image formed by the imaging system (lenses 124, 126, 128). The imaging device 130 includes, for example, a CCD camera having two-dimensionally arranged solid-state imaging devices. The imaging device 130 captures an electron microscope image and outputs information on the electron microscope image.

The charged particle beam device 100 is installed on a frame 150 via a vibration isolator 140 in the illustrated example.

2. Main Part of Charged Particle Beam Device Next, as main parts of the charged particle beam device according to the present embodiment, the sample container 10, the cartridge 2, the sample exchange device 100A, and the sample holder 24 will be described with reference to FIGS. while explaining.
FIG. 2 is a diagram schematically showing the main part of the charged particle beam device 100 according to this embodiment. In addition, in FIG. 2, X-axis, Y-axis, and Z-axis are illustrated as mutually orthogonal axes. 3A and 3B are diagrams schematically showing the cartridge 2, where (A) shows a top view and (B) shows a side view. 4A and 4B are diagrams showing an example of the sample holding portion 24, where (A) shows a top view and (B) shows a sectional view taken along the line AA of FIG. 4A.

(1) Sample Container and Cartridge As shown in FIG. 2 , the sample container 10 is attached to the sample exchange device 100A of the charged particle beam device 100 . The sample container 10 is a container for transporting the cooled sample S. A sample S and a coolant 6 for cooling the sample S are accommodated in the sample container 10 .

A sample container 10 accommodates a magazine 4 in which cartridges 2 are attached. A cooled sample S is fixed to the cartridge 2 by a fixing member (not shown).

The sample S is, for example, a biological sample or a sample such as a polymeric material whose structure is likely to be destroyed by a charged particle beam such as an electron beam or an ion beam.

As shown in FIG. 3, the cartridge 2 is a substantially rectangular plate member. The cartridge 2 is formed with a through-hole 201 penetrating vertically, and the sample S is fixed onto the through-hole 201 by a fixing member (not shown).

A locking hole 202 penetrating in the vertical direction is formed on one end side (the right side in FIG. 3) of the cartridge 2 in the longitudinal direction. The locking hole 202 is formed in a substantially rectangular shape. A locking edge 203 is formed at the edge of the locking hole 202 on one end side (the right side in FIG. 3) in the longitudinal direction of the cartridge 2 so that the size of the hole increases toward the upper surface of the cartridge 2. is formed.

As shown in FIG. 2, cartridge 2 is attached to magazine 4 . In the illustrated example, a plurality (three) of cartridges 2 are attached to the magazine 4 . The cartridge 2 and magazine 4 are desirably made of a material with good thermal conductivity.

The sample S is fixed in the cartridge 2 after being cooled to, for example, liquid nitrogen temperature or lower (for example, cryogenic temperature). A cartridge 2 to which a sample S is fixed is attached to a magazine 4 and transported by a sample container 10 . Here, the case where the cartridge 2 to which the sample S is fixed is attached to the magazine 4 and accommodated in the sample container 10 has been described. may be accommodated in the sample container 10 .

The coolant 6 is liquid nitrogen, for example. Refrigerant 6 may be liquid methane, liquid ethane, or liquid butane. The coolant 6 is not particularly limited as long as it can cool the sample S and is evacuated and solidified by the vacuum exhaust device 50 described later.

A heat-conducting member (not shown) is provided in the sample container 10 to separate the sample storage space in which the magazine 4 is stored from the coolant storage space in which the coolant 6 is stored. Also, the sample container 10 is connected to a sample exchange chamber 30, which will be described later, with a gate valve 40 closed. The sample container 10 is connected to the sample exchange chamber 30 via a connecting member 42 in the illustrated example. An O-ring 44 is attached to the end surface of the connecting member 42 , and the space between the sample container 10 and the connecting member 42 is sealed by the O-ring 44 . The sample container 10 is evacuated by the evacuation device 50 with the gate valve 40 closed.

(2) Specimen Exchanger Next, the specimen exchange device 100A will be described. The sample exchanging device 100A is provided at a position facing the goniometer 28 with the lens barrel 22 interposed therebetween, as shown in FIG. Note that the place where the sample exchange device 100A is installed is not particularly limited as long as the sample S can be exchanged in the sample chamber 20 .

As shown in FIG. 2, the sample exchange apparatus 100A includes a sample exchange chamber 30, a gate valve 40, an evacuation device 50, a sample storage section 60, a cooling section 70, a first transfer rod 80, and a second and a transport rod 90 .

The sample exchange chamber 30 is connected to the sample chamber 20 . A gate valve 32 is provided between the sample exchange chamber 30 and the sample chamber 20 . The gate valve 32 is a valve used as a vacuum partition between the sample exchange chamber 30 and the sample chamber 20 . By opening the gate valve 32, the sample exchange chamber 30 and the sample chamber 20 are communicated with each other. Also, by closing the gate valve 32, the sample exchange chamber 30 and the sample chamber 20 are isolated.

The sample exchange chamber 30 is a space surrounded by a vacuum container 34 . The sample exchange chamber 30 is evacuated by the evacuation device 50 . Thereby, the sample exchange chamber 30 can be kept in a vacuum. A sample storage section 60 is provided in the sample exchange chamber 30 .

A gate valve 40 is arranged between the sample exchange chamber 30 and the sample container 10 . The gate valve 40 is arranged between the sample exchange chamber 30 and the sample container 10 when the sample container 10 is connected to the sample exchange chamber 30 . The gate valve 40 is a valve used as a vacuum partition between the sample exchange chamber 30 and the sample container 10 . By opening the gate valve 40, the sample exchange chamber 30 and the sample container 10 are communicated with each other. Also, by closing the gate valve 40, the sample exchange chamber 30 and the sample container 10 are isolated.

The evacuation device 50 evacuates the sample container 10 . The vacuum evacuation device 50 can evacuate the sample container 10 while the sample container 10 is connected to the sample exchange chamber 30 and the gate valve 40 is closed. As a result, the sample storage space and the coolant storage space of the sample container 10 are evacuated, and the freezing point of the coolant 6 (for example, liquid nitrogen) stored in the coolant storage space is raised, so that the coolant 6 can be solidified. The evacuation device 50 can also evacuate the sample container 10 while the gate valve 40 is open.

The evacuation device 50 evacuates the sample container 10 through an evacuation pipe 52 . The exhaust pipe 52 is connected to the connecting member 42 in the illustrated example. A solenoid valve 54 is provided in the exhaust pipe 52 .

The evacuation device 50 further evacuates the sample exchange chamber 30 . The evacuation device 50 evacuates the sample exchange chamber 30 through an evacuation pipe 56 . A solenoid valve 58 is provided in the exhaust pipe 56 .

As the evacuation device 50, for example, an oil rotary vacuum pump (rotary pump), an ion pump, a scroll pump, a turbomolecular pump, or the like can be used.

The sample storage section 60 is provided in the sample exchange chamber 30 . The sample storage unit 60 can hold the sample S. The sample storage section 60 can hold a plurality of samples S. FIG. In the illustrated example, the sample storage section 60 holds a plurality of cartridges 2 to which samples S are fixed. The sample storage section 60 has, for example, the same configuration as the magazine 4 .

The sample storage section 60 is cooled by the cooling section 70 . Therefore, the sample S can be stored in a cooled state. The sample storage section 60 is made of, for example, a material with high thermal conductivity.

The cooling section 70 cools the sample storage section 60 . The cooling unit 70 includes, for example, a tank containing a coolant (for example, a liquid nitrogen tank containing liquid nitrogen) 72, and a heat conducting member 74a that thermally connects the tank 72 and the sample storage unit 60. It is The cooling unit 70 cools the sample storage unit 60 by cooling the heat conducting member 74 a with the refrigerant in the tank 72 .

The cooling section 70 further cools the first transport rod 80 and the second transport rod 90 . The cooling unit 70 further includes a thermally conductive member 74b that thermally connects the tank 72 and the first transport rod 80, and a thermally conductive member 74c that thermally connects the tank 72 and the second transport rod 90. is composed of The heat conducting members 74a, 74b, 74c are, for example, copper wires.

The first transport rod 80 transports the sample S between the sample container 10 and the sample exchange chamber 30 . Here, the first transport rod 80 transports the sample S by holding and transporting the magazine 4 . Specifically, the first transport rod 80 can grip the magazine 4 at its tip and move the gripped magazine 4 in the Z direction. The first transport rod 80 transports the magazine 4 to the sample exchange chamber 30 by gripping the magazine 4 in the sample container 10 and moving it in the +Z direction (upward in FIG. 2). The first transport rod 80 can also transport the magazine 4 (sample S) in the sample exchange chamber 30 to the sample container 10 .

The first transport rod 80 is cooled by the cooling section 70 . Therefore, even if the first transport rod 80 touches the cooled magazine 4, the magazine 4 can maintain its temperature.

The second transport rod 90 transports the sample S between the first transport rod 80 and the sample storage section 60 . Here, the second transport rod 90 transports the sample S by holding and transporting the cartridge 2 to which the sample S is fixed. Specifically, the second transport rod 90 can grip the cartridge 2 at its tip and move the gripped cartridge 2 in the X direction. The second transport rod 90 takes out the cartridge 2 from the magazine 4 held by the first transport rod 80 and moves the cartridge 2 in the -X direction (left direction in FIG. 2) to move the cartridge 2 to the sample storage section 60. transport. The second transport rod 90 can also take out the cartridge 2 from the sample storage section 60 and transport it to the magazine 4 held by the first transport rod 80 .

The second transport rod 90 further transports the sample S between the sample storage section 60 and the sample chamber 20 . The second transport rod 90 takes out the cartridge 2 from the sample storage section 60 and transports the cartridge 2 to the sample chamber 20 by moving it in the +X direction (right direction in FIG. 2). The second transport rod 90 transports the sample S to the sample holder 24 in the sample chamber 20 in the illustrated example. The second transport rod 90 can also transport the cartridge 2 (sample S) from the sample chamber 20 to the sample storage section 60 .

The second transport rod 90 further transports the sample S between the sample chamber 20 and the first transport rod 80 . The second transport rod 90 takes out the cartridge 2 from the sample chamber 20 (sample holder 24) and transports the cartridge 2 to the first transport rod 80 by moving it in the -X direction. The second transport rod 90 can also transport the cartridge 2 (sample S) from the first transport rod 80 to the sample chamber 20 .

The second transport rod 90 is cooled by the cooling section 70 . Therefore, even if the second transport rod 90 touches the cooled cartridge 2, the cartridge 2 can maintain its temperature.

(3) Sample Holding Section Next, the sample holding section 24 will be described. As shown in FIG. 4 , the sample holding section 24 includes a base section 241 , a mounting section 242 , a locking section 243 , a pressing section 244 and a temperature detection mechanism 245 .

The base portion 241 is a substantially cylindrical member, and one end portion (not shown) is connected to the sample holder 26 (see FIG. 2). A pair of locking portion holding portions 241a, 241a are integrally formed at the other end portion (the left end portion in FIG. 4) of the base portion 241. As shown in FIG. The locking portion holding portions 241a, 241a are substantially flat plate-shaped members arranged along the X direction. In addition, the pair of locking portion holding portions 241a, 241a are arranged so that the inner surfaces thereof face each other with a predetermined distance in the Y direction. A shaft portion 241b that supports the locking portion 243 is provided between the pair of locking portion holding portions 241a, 241a.

A mounting portion 242 extending along the X direction is provided below one end side (left side in FIG. 4) of the locking portion holding portions 241a, 241a in the X direction. The upper surface of the mounting portion 242 is formed substantially flat, and the cartridge 2 is mounted thereon.

The locking portion 243 includes a locking base portion 243a formed with a shaft hole, and a locking arm portion 243b integrally formed with the locking base portion 243a and extending along the X direction. there is The locking base portion 243a is arranged between the pair of locking portion holding portions 241a, 241a. By inserting the shaft portion 241b into the shaft hole of the locking base portion 243a, the locking portion 243 is rotatably supported by the locking portion holding portions 241a, 241a.

When the locking portion 243 is not pressed by the pressing portion 244, the locking portion 243 is moved to the position of the locking portion 243 shown in FIG. ) and waits.

An inclined surface portion 243c is formed on the distal end side (left side in FIG. 4) of the locking arm portion 243b so as to contact the locking edge 203 (see FIG. 3) of the cartridge 2 without a gap.

The pressing portion 244 is a substantially bar-shaped member extending along the X direction and penetrates through the base portion 241 and the sample holder 26 .

One end of the pressing portion 244 is connected to the motor 29 . As a result, when the motor 29 is driven, the pressing end portion 244a, which is the other end portion of the pressing portion 244 (the left end portion in FIG. 4), moves between the pair of locking portion holding portions 241a, 241a in the X direction. It is movable.

When the pressing end portion 244a moves leftward from an arbitrarily settable initial position (for example, the position shown in FIG. 4) and contacts the base end side of the locking arm portion 243b (right side in FIG. 4), the locking is performed. The arm portion 243b is pressed by the pressing end portion 244a. When the locking arm portion 243b is pressed by the pressing end portion 244a, the distal end side (the left side in FIG. 4) of the locking arm portion 243b rotates in the direction of arrow R in FIG. 4B. As a result, the tip of the locking arm portion 243b enters the locking hole 202 (see FIG. 3) of the cartridge 2 on the mounting portion 242. As shown in FIG. The inclined surface portion 243 c of the locking arm portion 243 b abuts against the locking edge 203 , whereby the locking arm portion 243 b locks the cartridge 2 .

The temperature detection mechanism 245 includes a temperature sensor (not shown) capable of detecting the temperature near the sample holder 24 in the sample chamber 20 . This temperature sensor is connected to a temperature controller 301 to be described later, and outputs detection results to the temperature controller 301 .

3. Circuit Configuration of Charged Particle Beam Device Next, the circuit configuration of the charged particle beam device 100 will be described. FIG. 5 is a functional block diagram showing the circuit configuration of the charged particle beam device 100. As shown in FIG.
As shown in FIG. 5, the circuit configuration of the charged particle beam device 100 includes a control board 300, a temperature controller 301, and a motor 29, which are electrically connected to each other.

The control board 300 has an FPGA (field-programmable gate array) as a control device. The control board 300 controls various operations of the charged particle beam device 100 . The control board 300 is connected to the temperature controller 301 and the motor 29 .

The temperature controller 301 transmits temperature information to the control board 300 based on the detection result input from the temperature sensor of the temperature detection mechanism 245 (see FIG. 4). The control board 300 determines the driving amount (number of steps) of the motor 29 based on the received temperature information, and drives the motor 29 .

In this embodiment, a first drive amount and a second drive amount are set as the drive amount. When the temperature indicated by the received temperature information is 0° C. or less, the control board 300 determines the driving amount to be the first driving amount. On the other hand, when the temperature indicated by the received temperature information is higher than 0.degree.

Since the rotation amount (movement amount) of the locking portion 243 is determined according to the drive amount (number of steps) of the motor 29, the control board 300 is controlled according to the temperature in the sample chamber detected by the temperature detection unit. A control section is configured to determine the amount of movement of the stopping section.

When the charged particle beam device 100 is assembled, the first driving amount is set such that the temperature in the vicinity of the sample holder 24 in the sample chamber 20 is set to 0° C. or lower, and then the locking arm 243b engages the cartridge 2. It is set in advance by measuring the drive amount of the motor 29 when stopping. Specifically, the motor 29 is driven to move the pressing end portion 244a from the initial position (for example, the position shown in FIG. 4) to the position where the locking arm portion 243b securely locks the cartridge 2 (locking arm portion The first drive amount is set by measuring the drive amount of the motor 29 when the motor 29 is moved to a position where the motor 29 stops rotating due to the contact between the inclined surface portion 243c of 243b and the locking edge 203. .

The second drive amount is set smaller than the set first drive amount. In this embodiment, it is set to 95% of the first driving amount. Note that the second driving amount is set so that the temperature near the sample holding portion 24 in the sample chamber 20 is higher than 0° C., and then the locking arm portion 243b is moved to the cartridge 2 in the same manner as the setting of the first driving amount. may be set by measuring the driving amount of the motor 29 when locking. The first driving amount and the second driving amount can be reset at arbitrary timing.

Although not shown, the control board 300 includes the temperature controller 301, the motor 29, various components of the charged particle beam device 100, for example, the first transport rod 80 and the second transport rod 90, and the like. Electrically connected to control operation of the arrangement.

4. Operation of Charged Particle Beam Device (1) Overview of Operation Next, an overview of the operation of the charged particle beam device 100 will be described. 6 to 9 are diagrams for explaining the outline of the operation of the charged particle beam device 100. FIG. Specifically, the operation of introducing the sample S from the sample container 10 into the sample chamber 20 and the operation of taking out the sample S from the sample chamber 20 will be described. A case where liquid nitrogen is used as the coolant 6 will be described here. Further, in the sample container 10, a magazine 4 having cartridges 2 attached therein is accommodated in a sample accommodation space cooled in advance by a coolant 6. As shown in FIG.

First, the operation of introducing the sample S from the sample container 10 into the sample chamber 20 will be described. In the sample exchange apparatus 100A, the inside of the sample exchange chamber 30 is previously evacuated by the evacuation device 50 and kept in vacuum. That is, the solenoid valve 58 is in an open state. Also, the first transport rod 80 , the second transport rod 90 , and the sample storage section 60 are always cooled by the cooling section 70 . Also, the gate valve 32 is closed.

First, as shown in FIG. 6, the inside of the sample container 10 attached to the sample exchanging apparatus 100A is evacuated, the electromagnetic valve 54 is closed, and then the gate valve 40 is opened.

Next, as shown in FIG. 7, the magazine 4 is grasped using the first transport rod 80, and the first transport rod 80 is moved in the +Z direction (upward direction in FIG. 7) to move the magazine 4 into the sample container 10. from the sample exchange chamber 30 into the sample exchange chamber 30 . Then, the gate valve 40 is closed.

Next, as shown in FIG. 8, the second transport rod 90 is used to take out the cartridge 2 from the magazine 4 held by the first transport rod 80 . Then, the gate valve 32 is opened and the second transport rod 90 is moved in the +X direction (rightward direction in FIG. 7) to introduce the cartridge 2 (sample S) into the sample chamber 20 . The sample holding section 24 holds the cartridge 2 . Thereby, the sample S can be introduced from the sample container 10 into the sample chamber 20 .

Thereafter, as shown in FIG. 9, the second transport rod 90 is returned to its original position, the gate valve 32 is closed, and observation of the sample S is started.

Next, the operation of taking out the sample S from the sample chamber 20 will be described. As shown in FIG. 8, the gate valve 32 is opened, the second transfer rod 90 is moved into the sample chamber 20, and the cartridge 2 (sample S) held by the sample holding section 24 is gripped.

Next, as shown in FIG. 7, the second transport rod 90 holding the cartridge 2 is moved in the -X direction (left direction in FIG. 7) to transport the cartridge 2 from the sample chamber 20 to the sample exchange chamber 30. . Then, the gate valve 32 is closed. Thereby, the sample S can be taken out from the sample chamber 20 .

(2) Operation of Sample Holding Section Next, the details of the operation when the sample holding section 24 holds the cartridge 2 will be described with reference to FIGS. 10 and 11. FIG. 10A and 10B are diagrams (part 1) for explaining the operation of the sample holding unit 24 of the charged particle beam device 100, where (A) is a top view and (B) is B- of FIG. 10 (A). The B line sectional drawing is shown. 11A and 11B are diagrams (part 2) for explaining the operation of the sample holding unit 24 of the charged particle beam device 100, where (A) shows a top view and (B) shows a C- The C line sectional drawing is shown. 10 and 11, illustration of the second transport rod 90 is omitted.

As shown in FIG. 10 , the cartridge 2 introduced into the sample chamber 20 by the second transport rod 90 is placed on the placement section 242 .

In FIG. 10, the locking portion 243 is on standby at the standby position described above. Also, the pressing end 244a is at the initial position.
When the cartridge 2 is placed on the placement portion 242, the control board 300 requests the temperature controller 301 to transmit the temperature information, and determines the driving amount (number of steps) of the motor 29 based on the received temperature information. , drives the motor 29 .

As described above, the control board 300 determines the drive amount to be the first drive amount when the temperature indicated by the received temperature information is 0° C. or lower, and when the temperature indicated by the received temperature information is higher than 0° C. , the drive amount is determined to be the second drive amount.

When the pressing end portion 244a moves from the initial position in response to the drive of the motor 29 and contacts the base end side (the right side in FIG. 10) of the locking arm portion 243b, the locking arm portion 243b is moved by the pressing end portion 244a. pressed. When the locking arm portion 243b is pressed by the pressing end portion 244a, the distal end side (the left side in FIG. 10) of the locking arm portion 243b rotates in the direction of arrow R in FIG. 10B.

As a result, the tip of the locking arm portion 243b enters the locking hole 202 of the cartridge 2 on the mounting portion 242, as shown in FIG. The inclined surface portion 243 c of the locking arm portion 243 b abuts against the locking edge 203 , whereby the locking arm portion 243 b locks the cartridge 2 . That is, the sample holding portion 24 holds the cartridge 2 (sample S).

When the sample S is taken out of the sample chamber 20, after the cartridge 2 (sample S) held by the sample holding portion 24 is gripped by the second transport rod 90, the control board 300 drives the motor 29, The pressing end 244a is moved to the initial position. When the pressing end portion 244a is separated from the locking arm portion 243b, the locking portion 243 is rotated in the direction opposite to the arrow R shown in FIG. This allows the second transport rod 90 to take out the sample S from the sample chamber 20 .

In the charged particle beam device 100 of the present embodiment, the control board 300 determines the drive amount to be the first drive amount when the temperature near the sample holder 24 in the sample chamber 20 is 0° C. or less. On the other hand, when the temperature is higher than 0° C., the control board 300 determines the driving amount to be the second driving amount corresponding to 95% of the first driving amount. Further, when the motor 29 is driven by the first drive amount, the rotation amount (movement amount) of the locking portion 243 is larger than when the motor is driven by the second drive amount.

Therefore, even if the sample is cooled and the inside of the sample chamber 20 is cooled, the rotation amount (movement amount) of the locking portion 243 is increased even if the members constituting the cartridge 2 and the sample holding portion 24 are contracted. Thus, the locking portion 243 can securely lock the cartridge 2 . That is, it is possible to suppress the occurrence of a gap between the engaging portion 243 and the cartridge 2, and to suppress the occurrence of noise in the image to be observed.

Also, the first driving amount and the second driving amount can be reset at arbitrary timing. Therefore, due to aged deterioration due to abrasion of the locking portion 243 and the cartridge 2, a gap is generated between the locking portion 243 and the cartridge 2 when the already set first driving amount and the second driving amount are used. In such a case, the first driving amount and the second driving amount should be reset before observing the sample. As a result, it is possible to suppress the generation of noise in the image to be observed, which is caused by aging deterioration of the member.

In addition, since the first driving amount and the second driving amount can be set according to the cartridge 2 used for observation, a gap between the locking portion 243 and the cartridge 2 due to variations in the machining accuracy of the cartridge 2 can be generated. In addition, it is possible to suppress the occurrence of noise in an image to be observed.

In the above-described embodiment, the charged particle beam device is a transmission electron microscope, but the charged particle beam device according to the present invention is not particularly limited as long as it uses charged particle beams such as electrons and ions. . The charged particle beam device according to the present invention is, for example, an electron microscope such as a scanning transmission electron microscope (STEM) or a scanning electron microscope (SEM), an electron beam microanalyzer (EPMA), a focused ion beam device (FIB device), an electron beam It may be an exposure device or the like.

The present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same function, method, and result, or configurations that have the same purpose and effect). Moreover, the present invention includes configurations obtained by replacing non-essential portions of the configurations described in the embodiments. In addition, the present invention includes a configuration that achieves the same effects or achieves the same purpose as the configurations described in the embodiments. In addition, the present invention includes configurations obtained by adding known techniques to the configurations described in the embodiments.

2 Cartridge 4 Magazine 6 Refrigerant 10 Sample container 20 Sample chamber 22 Barrel 24 Sample holder 26 Sample holder 28 Goniometer 29 Motor 30 Sample Exchange chamber 50 Vacuum evacuation device 60 Sample storage unit 70 Cooling unit 80 First transport rod 90 Second transport rod 100 Charged particle beam device 100A Sample exchange device 110 Charging Particle beam source, 120... Optical system, 122... Irradiation lens, 124... Objective lens, 126... Intermediate lens, 128... Projection lens, 130... Imaging device, 140... Vibration isolator, 150... Base, 160... Sample holding mechanism, 201 through hole 202 locking hole 203 locking edge 241 base portion 241a locking portion holding portion 241b shaft portion 242 mounting portion 243 locking portion 243a locking portion Stopping base portion 243b Locking arm portion 243c Inclined surface portion 244 Pressing portion 244a Pressing end portion 245 Temperature detection mechanism 300 Control board 301 Temperature controller

Claims (2)

a sample holding mechanism that holds a sample fixing member to which the sample is fixed in the sample chamber;
A charged particle beam device comprising a control unit that controls the sample holding mechanism,
The sample holding mechanism is
a mounting section on which the sample fixing member is mounted;
a locking portion that moves from a predetermined initial position and locks the sample fixing member placed on the mounting portion;
a temperature detection unit that detects the temperature in the sample chamber,
the locking portion moves in a direction to press the sample fixing member against the mounting portion when locking the sample fixing member;
A charged particle beam apparatus, wherein the control unit determines the amount of movement of the locking unit according to the temperature in the sample chamber detected by the temperature detection unit. 2. The method according to claim 1, wherein when the temperature inside the sample chamber is equal to or lower than a predetermined temperature, the control unit determines a larger amount of movement than when the temperature inside the sample chamber exceeds a predetermined temperature. A charged particle beam device as described.

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