Stage

Abstract

To provide a stage that can be transported under vacuum or the like.SOLUTION: A stage according to the present invention includes a sample base on which a sample is mounted, a shutter function capable of isolating the atmosphere inside the stage from the atmosphere outside the stage, and a sealing portion. In a preferred embodiment of the stage according to the present invention, the stage further includes a first valve capable of automatic evacuation. In a preferred embodiment of the stage according to the present invention, the stage further includes a second valve whose degree of opening and closing can be adjusted.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a stage, and particularly to a stage capable of being transferred under a vacuum or the like.

Background Art

[0002] In recent years, high-resolution analysis in electron microscopes such as transmission electron microscopes (TEMs) and scanning transmission electron microscopes (STEMs) has advanced. For example, high-resolution analysis from the nano-order to the pico-order has been demanded. These days, "in-situ observation" in which cooling (or heating, electric field application, magnetic field application, rotation, etc.) is performed while observing a sample in an electron microscope has attracted attention. In particular, sample cooling is considered effective for reducing damage to the sample by an electron beam, and sample cooling from this perspective has also been attempted.

[0003] In addition, although the magnification of an SEM is lower than that of a TEM, since there are fewer restrictions on the size of the observation sample, a large sample can be observed, and it is easier to use than a TEM, so the difficulty of observation analysis is lower than that of a TEM. Therefore, electron microscope manufacturers are developing products that can observe various objects.

[0004] For example, as an apparatus having a cooling means, in the sample chamber of a scanning electron microscope, there is provided a cooling stage on which a sample from which moisture has been sublimated is placed, and a manipulator that extends on this cooling stage and cuts out necessary components of the sample under the observation of the scanning electron microscope. A sample processing apparatus using a scanning electron microscope thus constituted is known (Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Under such cooling needs, in the prior art including the above-mentioned Patent Document 1, the sample fixing method of the existing cooling stage is only the method of sticking the sample on the upper surface of the sample pedestal, and the cooling is only performed from the lower surface of the sample.

[0007] Also, in the prior art, the observation of the sample is realized by transferring it from the outside to the SEM stage cooled with liquid nitrogen by vacuum. That is, a method of inserting a cartridge on which the sample is placed during SEM using a rod or the like is adopted. However, since this is transferred from the outside of the electron microscope, it is physically impossible to bring wiring for conducting electricity or the like into the vacuum part. For this reason, many research users eagerly desire an SEM stage that can observe the sample while cooling the sample and also conducting electricity or the like.

[0008] Therefore, an object of the present invention is to provide a stage that can be transferred in a vacuum or the like.

Means for Solving the Problems

[0009] In order to achieve the above object, as a result of intensive studies on the mechanism of the stage, the present inventor has found the present invention.

[0010] That is, the stage of the present invention is characterized by having a sample pedestal on which a sample is mounted, a shutter function capable of blocking the atmosphere inside and outside the stage, and a seal portion.

[0011] Further, in a preferred embodiment of the stage of the present invention, it further has a first valve capable of automatic exhaust.

[0012] Further, in a preferred embodiment of the stage of the present invention, it further has a second valve capable of adjusting the opening and closing degree.

[0013] Also, in a preferred embodiment of the stage of the present invention, further, it is characterized by having a motor capable of opening and closing the shutter of the shutter function.

[0014] Also, in a preferred embodiment of the stage of the present invention, further, it is characterized by having a feed-through part.

[0015] Also, in a preferred embodiment of the stage of the present invention, further, it is characterized by having an electrode part.

[0016] Also, in a preferred embodiment of the stage of the present invention, the sample pedestal is characterized by comprising an attachment mounting device.

[0017] Also, in a preferred embodiment of the stage of the present invention, further, it is characterized by having a cooling part.

[0018] Also, in a preferred embodiment of the stage of the present invention, it is characterized by having a thermoelectric element installed in proximity to the cooling part.

[0019] Also, in a preferred embodiment of the stage of the present invention, the attachment mounting device is characterized by being a screw hole or a clamp.

[0020] Also, in a preferred embodiment of the stage of the present invention, the thermoelectric element is a thermoelectric element utilizing at least one effect selected from the Peltier effect and the Thomson effect.

[0021] Also, in a preferred embodiment of the stage of the present invention, it is characterized in that the heat dissipation side of the thermoelectric element is in contact with the cooling part.

[0022] Also, in a preferred embodiment of the stage of the present invention, the cooling part is characterized by being composed of at least one of a solid refrigerant, a liquid refrigerant, and a gas refrigerant.

[0023] Further, in a preferred embodiment of the stage of the present invention, the sample pedestal and the thermoelectric element are in contact with each other.

Advantages of the Invention

[0024] According to the stage of the present invention, there is an advantageous effect that transfer can be performed under vacuum, Ar, etc. Further, according to another aspect of the stage of the present invention, electrodes and the like can also be arranged, and for example, there is an advantageous effect that it is possible to observe an object while passing an electric current through a battery.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0026] The stage of the present invention is characterized by having a sample pedestal for mounting a sample, a shutter function capable of blocking the atmosphere inside and outside the stage, and a seal portion. In the present invention, the sample pedestal for mounting a sample is not particularly limited as long as it can mount a sample to be observed in an electron microscope, including its shape, structure, etc. Further, in the present invention, it has a shutter function capable of blocking the atmosphere inside and outside the stage. By implementing the function of the shutter, if it has a structure that enables independent vacuum transfer, it is possible to have a structure in which electrodes can also be arranged, enabling observation while flowing electricity to a battery. For example, in the present invention, in a glove box, after making it vacuum to remove moisture, etc., it can be filled with Ar. A sample is attached in the glove box, and after sealing it with a vacuum transfer shutter with a cooling function under Ar gas filling or vacuum by the shutter function, the stage can be transferred to the SEM under vacuum or Ar.

[0027] In the present invention, the seal portion is not particularly limited as long as it can block the atmosphere inside and outside the stage during transfer under vacuum or the like. As long as the atmosphere inside the stage (sample installation side) and the outside can be blocked, the seal portion may be provided on the stage side, on the shutter side, or on one or both sides.

[0028] In a preferred embodiment of the stage of the present invention, it further has a first valve capable of automatic exhaust. For example, in a glove box, it is possible to achieve non-exposure to the atmosphere by filling with Ar gas, bringing it to the SEM, evacuating the SEM, and opening the lid. However, if the shutter is suddenly opened, a large amount of argon may flow into the SEM and the SEM may malfunction. Therefore, by having a first valve capable of automatic exhaust, it is possible to relieve the inflow. For example, as the first valve capable of automatic exhaust, by providing a check valve, the valve can release the differential pressure generated in the SEM and the stage chamber, and it is possible to evacuate the chamber or the SEM etc. more safely.

[0029] In a preferred embodiment of the stage of the present invention, it further has a second valve capable of adjusting the opening and closing degree. By having a second valve capable of adjusting the opening and closing degree, it can be slowly replaced from vacuum to an Ar atmosphere or the like. For example, when transferring from the SEM to the glove box, since the chamber of the stage is in a vacuum, as an on-off valve for slowly replacing the vacuum with argon in the glove box, a second valve capable of adjusting the opening and closing degree can be utilized.

[0030] In a preferred embodiment of the stage of the present invention, it further has a motor capable of opening and closing the shutter having the shutter function. By the motor, the shutter can be smoothly opened and closed. The shutter may be directly operated by the motor, or as described later, for example, the shutter may be opened and closed via a gear or the like. It is also possible to remotely operate the shutter by motor drive.

[0031] Also, in a preferred embodiment of the stage of the present invention, it further has a feed-through portion. As described above, in the conventional atmospheric non-exposure, the sample is placed on the cartridge and transferred in vacuum from the outside of the electron microscope, so the design is such that voltage cannot be applied. To allow the flow of electricity, a feed-through that isolates the wiring from the vacuum is required. A feed-through can be defined as a vacuum component attached to a vacuum wall that separates the vacuum state from the atmosphere in order to transport and control electrical signals, physical movements, fluids, etc. into the interior of a device maintaining a vacuum state. In the present invention, the field-through portion enables, for example, observation of a sample while applying a voltage.

[0032] Also, in a preferred embodiment of the stage of the present invention, it further has an electrode portion. One or more electrode portions can be provided. In the present invention, it is possible to attach the electrode shape required by the user. Thereby, it is also possible to customize the way of applying electricity required by the researcher.

[0033] Also, in a preferred embodiment of the stage of the present invention, the sample pedestal is characterized by comprising an attachment mounting device. That is, in the embodiment comprising the attachment mounting device of the present invention, it becomes possible to easily attach and detach the attachment, and various attachments can be exchanged. The position where the attachment mounting device is provided may be the position of the above-described electrode, or may be provided separately from the electrode.

[0034] Also, in a preferred embodiment of the stage of the present invention, it further has a cooling unit. In the present invention, the cooling unit is not particularly limited as long as it can cool the sample to be observed in the electron microscope, including its shape, structure, etc. The sample pedestal portion can be cooled by the cooling unit or a Peltier element. However, since the portions other than the cooling unit are at a higher temperature, when an attachment is connected and fixed to a portion outside the periphery of the cooling unit (outside the cooling system), the attachment will be heated by receiving heat from outside the cooling system. In this case, when the attachment is heated, heat will also transfer to the sample, resulting in the cooled sample warming up and the cooling effect being reduced. In the embodiment where the sample pedestal of the present invention is equipped with an attachment mounting device, the attachment exists within the cooling system via the attachment mounting device, and thus it becomes possible to cool the sample with minimal heat loss.

[0035] Also, in a preferred embodiment of the stage of the present invention, from the perspective of being able to firmly and reproducibly fix the attachment, the attachment mounting device is characterized by being a screw hole or a clamp. In the present invention, since the attachment mounting device, for example, includes a screw portion, etc., it is easy to replace the attachment according to the purpose. Double-sided tape and adhesives are difficult to remove after fixing the attachment and are not intended for reuse. Also, each time the attachment is replaced, the thermal contact condition between the attachment and the sample pedestal portion changes, and it is difficult to control the posture of the attachment. In contrast, in the present invention, by attaching the attachment mounting device, the attachment, etc. can be reproducibly replaced, so it has the advantage of being able to flexibly respond to various applications.

[0036] Also, the attachment is not particularly limited as long as it can be attached. In a preferred embodiment of the stage of the present invention, the attachment is characterized in that it is at least one selected from a grid holding attachment for FIB, a sample fixing attachment, and an energizing attachment. In addition to the grid holding attachment for FIB and the upper surface fixing attachment, when observing the sample with the clamping direction horizontal, if it is cooled from the clamped portion, a temperature gradient can be created across the free end portion. In the present invention, an attachment capable of imparting such a temperature gradient can also be installed. An attachment having a cold trap function for preventing contamination by arranging a cooling member near the upper surface of the sample is also conceivable.

[0037] Here, when using the expression "Cold trap", it can be understood as a device that cools and captures trace floating substances (gases such as hydrocarbons) in a vacuum. That is, if there is gas in a vacuum, it is expected to be struck onto the sample along with the irradiation of the electron beam and deposited on the sample. When a cooling member is arranged near the upper surface as in the present invention, it is possible to realize a mechanism that surrounds the vicinity of the sample with a cooled metal member (cooling member) within a range that does not block electron beam irradiation or the like, creating a locally high-vacuum region. As a result, a mechanism can be constructed to cool and condense to collect the emitted gas, and ultimately, it is possible to prevent the gas present in the vacuum in the electron microscope from adhering to the sample.

[0038] Furthermore, when considering applications such as simultaneously energizing the sample while cooling, by fixing electrodes, sample fixing presses, etc. using (via) an attachment mounting device such as a screw portion, or by fixing and energizing the sample on an extended stage fixed by an attachment mounting device, the influence of external temperature can be reduced. In the present invention, such an attachment can also be mounted.

[0039] Further, in a preferred embodiment of the stage of the present invention, the attachment mounting device is characterized by being made of a member having thermal conductivity. Examples of members having high thermal conductivity include copper and copper alloys, aluminum and aluminum alloys, silver, gold, and the like. In the present invention, for example, an attachment mounting device such as a screw hole or the like is integrally provided on the sample pedestal portion of the stage for cooling a sample in a scanning electron microscope (SEM), enabling attachment of an attachment having a shape and form according to the purpose. As a result, since the attachment is also incorporated into the cooling system, various cooling modes can be realized with less influence of external heat.

[0040] Further, in a preferred embodiment of the stage of the present invention, the cooling unit is characterized by being composed of at least one of a solid refrigerant, a liquid refrigerant, or a gas refrigerant. In the cooling unit, the refrigerant can be appropriately set according to the application and is not particularly limited. From the viewpoint of versatility, a liquid can be mentioned as a preferred medium. If it is a liquid (such as water), the temperature can be adjusted using a general-purpose device (cooling chiller), but since it is a fluid, it can be a source of vibration. It is also possible to use liquid nitrogen or liquid helium as the liquid.

[0041] Further, in the present invention, from the viewpoint that it is possible to make the influence of vibration due to water flow or pulsating flow zero compared to water cooling, the cooling unit may be a solid refrigerant. That is, in the present invention, it is possible to cool the heat dissipation surface of a Peltier element or the like with a solid refrigerant such as dry ice. As a result, it is possible to make the influence of vibration due to water flow or pulsating flow zero compared to water cooling. Also, in the case of a solid, regarding the difficulty in adjusting the temperature of the cooling unit, it can be controlled using a thermoelectric element as described later.

[0042] On the other hand, even when the cooling gas is flowed in a minute flow rate, since the influence of vibration is small, these can also be utilized in the present invention. Examples of the cooling gas include those obtained by gasifying liquid nitrogen and taking it out. Thereby, it is possible to cool the sample well. In the present invention, the cooling gas is not limited to liquid nitrogen. It is considered that it is practical with almost no influence of vibration as long as the gas is simply passed through the heat dissipation surface weakly. Therefore, in the present invention, as described above, even when a solid refrigerant is actually used as the cooling unit, it is sufficient to direct the cold air with a gap instead of pressing it against the heat dissipation surface. Similarly, when using liquid nitrogen gas, it is possible to observe without being affected by vibration by passing the cooling gas through the heat dissipation surface. Regarding the difficulty in adjusting the temperature of the cooling unit, it is possible to control it using a thermoelectric element as described later.

[0043] Further, in a preferred embodiment of the stage of the present invention, it further has a thermoelectric element installed in proximity to the cooling unit. In the present invention, the arrangement position of the thermoelectric element is not particularly limited as long as it is installed in proximity to the cooling unit. By the thermoelectric element, it is possible to efficiently set the temperature required for the sample, that is, to control the temperature. In the aspect using a thermoelectric element, the response of cooling and heating is good and the influence of thermal drift can be suppressed as much as possible. Also, since the response of cooling and heating is improved, precise temperature control is possible. In the aspect using a thermoelectric element, cooling and heating can be realized with a single element simply by reversing the energization direction. At the same time, since the response of cooling and temperature rise is fast, it is easy to change to a predetermined temperature. Also, since precise temperature control is possible by adjusting the output of the input power, precise temperature control is possible and the influence of thermal drift can be suppressed as much as possible.

[0044] Also, in a preferred embodiment of the stage of the present invention, the heat dissipation side of the thermoelectric element is in contact with the cooling unit. That is, in the present invention, regarding the arrangement position of the thermoelectric element, it only needs to be installed in proximity to the cooling unit. For example, a structure in which a cooling unit such as a solid refrigerant is pressed against the heat dissipation side (heat dissipation surface side) may be used, or a structure in which cold air is applied with a gap may also be used. When applying cold air, natural convection or forced convection using a fan or the like may be employed. However, when forced convection generates vibration, depending on the degree of forced convection, natural convection is desirable. Even in the case of natural convection, since the solid refrigerant has a sufficiently low temperature, there is a large temperature gradient between the heat dissipation surface side and the cold air of the cooling unit such as the solid refrigerant, so sufficient heat transfer occurs and it is considered that the heat dissipation surface can be appropriately cooled. It should be noted that heat dissipation treatment by forced convection rather than natural convection and by water cooling rather than air cooling is effective.

[0045] Also, in a preferred embodiment of the stage of the present invention, the thermoelectric element is a thermoelectric element that utilizes at least one of the Peltier effect or the Thomson effect. The Peltier effect (also referred to as the Peltier effect) is an effect of converting electrical energy into thermal energy. When both ends of two different types of dissimilar metals (or semiconductors) are connected and an electric current is passed, a temperature difference occurs at both ends. It is particularly called a Peltier element and is used for cooling precision equipment, wine cellars, and the like. The Thomson effect refers to the effect of generating heat other than Joule heat (absorbing heat when the current is reversed) when an electric current is passed through a uniform metal (or dissimilar metals) having a temperature gradient. Both can generate heat or absorb heat.

[0046] Note that a heat dissipation member may be installed between the thermoelectric element and the cooling unit or the like from the viewpoint of efficient waste heat dissipation of the thermoelectric element.

[0047] In a preferred embodiment of the stage of the present invention, the thermoelectric element is a Peltier element from the viewpoint of having a good cooling / heating response and suppressing the influence of thermal drift as much as possible. The Peltier element is also called a Peltier device (thermo-module), which is a general term for elements utilizing the Peltier effect. The currently mainstream and most performant structure is called "π-shaped" and has a structure as shown in Fig. 2. By passing an electric current through a PN junction using a P-type semiconductor and an N-type semiconductor, heat dissipation can occur between P and N, and heat absorption can occur between N and P.

[0048] The principle is as follows. Fig. 2 shows an embodiment of a thermoelectric element applicable to the present invention. Fig. 2(a) shows a cross-sectional view of the Peltier element, and Fig. 2(b) shows a schematic diagram of the principle of the Peltier element. In Fig. 2(a), 21 is the metal on the hot side (mainly Cu), 22 is the ceramic substrate (mainly alumina), 23 is the heat dissipation surface, 24 is the N-type semiconductor, 25 is the P-type semiconductor, 26 is the electric wire, 27 is the power source, 28 is heat absorption, 29 is the conduction band of the N-type semiconductor, 30 is heat dissipation, 31 is the plus side, 32 is the heat absorption side, 33 is the valence band, 34 is the heat dissipation side, 35 is the minus side, 36 is the metal on the cold side (mainly Cu), 37 is the metal on the cold side (mainly Cu), 38 is the electron, 39 is the hole, and 40 is the conduction band of the P-type semiconductor, respectively.

[0049] In Fig. 2(a), the negative pole is connected to the metal 36 on the N-type semiconductor 24 side. Therefore, electrons are pushed up from the conduction band of this metal 36 to the conduction band 29 of the N-type semiconductor 24 by the voltage. At this time, since there is an energy gap between the conduction band of the metal 36 and the conduction band 29 of the N-type semiconductor 24, the electrons take thermal energy from the metal 36, resulting in cooling of this metal 36. Subsequently, the electrons flow and fall from the conduction band 29 of the N-type semiconductor 24 to the conduction band of the metal 21. Due to the energy gap between the two bands, the electrons release thermal energy. In this way, the metal 21 on the hot side is heated. Furthermore, the flowing electrons fall from the conduction band of the metal 21 into the holes 39 that have flowed through the P-type semiconductor 25, releasing thermal energy and heating the metal 21 on the hot side. In the P-type semiconductor 25, holes 39 are produced by the voltage and flow from the cold side 37 to the hot side 21. The electrons generated at that time are pushed up to the conduction band of the metal on the cold side by the voltage, taking the thermal energy corresponding to their energy gap and cooling the metal 37 on the cold side. In this way, when an electric current flows, heat is transported from the cold side to the hot side of the Peltier module. In addition to the thermal energy transported by the electric current, there is also thermal energy transported by heat conduction. However, since the direction of the heat flow by heat conduction is opposite, the performance of the Peltier module improves as it is reduced. That is, quickly removing the thermal energy on the hot side with a heat sink or the like enables the Peltier module to exhibit good performance. Briefly speaking, electrons transport (take) heat.

[0050] The semiconductor material is not particularly limited, and any of them can be applied. However, the Bi-Te-based semiconductor is considered to have the best performance and is the mainstream.

[0051] Regarding the performance of a Peltier device, generally, the performance of a Peltier device can be considered in terms of how much temperature difference ΔT can be created with respect to the temperature Th when the temperature of the heat dissipation side is kept constant. For example, for Th = 75, 50, 25 (°C), ΔT = 93, 85, 75, respectively. If the heat dissipation surface is simply continuously cooled, for example, at the liquid nitrogen temperature (-196 °C), it is considered that the temperature on the heat absorption side would exceed minus two hundred and several tens of degrees. However, in reality, due to the material characteristics, it is assumed that ΔT = 10 °C near liquid nitrogen. The lower the temperature, the less heat there is to excite electrons, resulting in a decrease in the Peltier cooling capacity. Also, the lower the temperature, the greater the electrical resistance of the semiconductor part, and as a result, self-heating occurs due to the current, leading to a decrease in the overall cooling capacity.

[0052] Also, in a preferred embodiment of the present invention, from the viewpoint that it is possible to set the temperature to a lower level by cooling the heat dissipation side of the thermoelectric element, the heat dissipation side of the thermoelectric element is in contact with the cooling part. In the following examples, the case of cooling is mainly described. However, in the present invention, it is also possible to heat using the thermoelectric element. During heating, since the lower surface of the thermoelectric element gets cold, it is necessary to warm the cooling part and use it (process at a temperature higher than the lower surface). In this case, it can act as a heating part instead of a cooling part.

[0053] In the case of heating, compared with the case of cooling, the phenomenon will simply be reversed, but the practicality also varies depending on the shape (whether it is a multi-stage type or not) of thermoelectric elements such as Peltier elements. Basically, when aiming for an extremely low temperature, a multi-stage thermoelectric element, for example, a Peltier element can be used. In this case, it can be structured like a pyramid where the area of the heat absorption surface (upper stage) is small and increases towards the heat dissipation surface. The reason for such a structure is that basically, the larger the area, the larger the heat absorption amount. So, the heat absorbed by the upper stage with a small area is dissipated by the elements in the lower stage with a larger area. When using it for heating by reversing the polarity of the current, it is not simple. There is a tendency for the heat from the lower stage with a large area to flow into the upper stage with a small area all at once. If the upper stage cannot receive all of this heat, the heat accumulates in the middle stage and the temperature tends to be higher than that of the upper stage. Therefore, in many Peltier elements, even when used on the heating side, it is considered that the temperature will be around +100 °C (the temperature at which the solder at the joint does not deteriorate). A Peltier element creates a heat absorption surface and a heat dissipation surface through the movement of electrons. In principle, it is possible to precisely control the temperature in the negative region from near room temperature by controlling the amount of current flowing through the Peltier element. Due to these effects, stable high-resolution observation becomes possible.

[0054] Also, in a preferred embodiment of the stage of the present invention, from the perspective of cooling after the sample pedestal portion, the sample pedestal and the thermoelectric element are in contact with each other.

Example

[0055] Hereinafter, a stage in an embodiment of the present invention will be described with reference to the drawings, but the present invention is not to be construed as being limited to those examples. Needless to say, it can be appropriately changed without departing from the gist of the present invention.

[0056] Figure 1 shows a conceptual diagram of the sample pedestal portion of the stage in one embodiment of the present invention. Figure 1(a) shows a top view of the sample pedestal portion of the stage in one embodiment of the present invention, Figure 1(b) shows a side view of the sample pedestal portion of the stage, and Figure 1(c) shows a perspective view of the sample pedestal portion of the stage. In Figure 1, 1 represents the sample pedestal, 2 represents an attachment mounting device or electrode, 3 represents a thermoelectric element (when a thermoelectric element is required), 4 represents a heat dissipation member, and 5 represents a cooling portion.

[0057] Referring to the figures, the roles of the components and the connection between the components of the sample pedestal of the stage in one embodiment of the present invention will be described as follows. First, there is a stage body. In Figure 1, it is an embodiment having a cooling portion 5. However, in the case of the above-mentioned heating, since the lower surface of the thermoelectric element cools during heating, it is necessary to warm the cooling portion and use it (process at a temperature higher than the lower surface). In this case, instead of the cooling portion, it can act as a heating portion. Also, in this example, a thermoelectric element 3 is used. However, in an embodiment where the thermoelectric element 3 is not used, the thermoelectric element 3 can be omitted. In this example, since it is an embodiment using the thermoelectric element 3, as shown in the figure, a heat dissipation member 4 may be provided as necessary. Also, in this example, the attachment mounting device 2 is specifically a screw hole, but as described above, it may be a clamp or the like. As long as the attachment can be attached and removed, it is not particularly limited. The attachment mounting device 2 is preferably made of a material with high thermal conductivity. Thereby, it is possible to avoid more heat loss. Note that when the attachment mounting device is not used, it can be an electrode 2.

[0058] Note that as long as the Peltier element and the sample pedestal portion are in thermal contact, they may be directly above or offset horizontally and extended. Also, in the figure, the clamp is standing vertically, but the sample may be clamped horizontally. An example of a feature is that the attachment hole or the electrode is integrated with the sample pedestal portion. The attachment hole or the electrode may be integrally processed, or only the screw hole portion may be separately manufactured and then press-fitted or adhered later.

[0059] Also, although not shown, a grid for FIB may be installed as an attachment. In this case, the FIB grid holding pedestal can be attached to the FIB grid holding attachment with copper screws or the like. It is also possible to fix the sample holding pedestal for FIB to the sample stage as a cooling attachment. The mesh for FIB can be sandwiched so that it stands vertically at the center of the FIB grid gap for use. By doing so, damage caused by an electron beam or an ion beam can be reduced by the cooling effect. If the pedestal part is made a little larger, a normal sample can also be clamped and observed. The structure may be such that the sample can be clamped horizontally.

[0060] Also, although not shown, it is also possible to fix the sample from above as an attachment. The upper surface of the observation sample can be fixed by the sample fixing attachment installed at the upper part. If the sample is fixed from above as an attachment and the attachment or the like is composed of a member having thermal conductivity, it is possible to cool the sample from the upper surface as well. In the present invention, by attaching the attachment mounting device, the attachment or the like can be replaced with good reproducibility, so that it has the advantage of being able to flexibly respond to various applications.

[0061] Next, FIG. 3 is a diagram showing a perspective view of a stage with a shutter function in one embodiment of the present invention. In FIG. 3, 50 is a shutter, 51 is a motor, 52 is a sample pedestal (below is a cooling part (if provided)), 53 is an attachment mounting device or electrode, 54 is a first valve, and 55 is a second valve. In FIG. 3, the shutter 50 is shown in an open state, and an example of the inside of the stage is shown. The shutter can be opened and closed, and although not shown, when the shutter is closed, the inside of the stage can be made a vacuum or an Ar atmosphere, and transfer of vacuum, etc. is possible. The motor 51 can open and close the shutter 50, as described later. 52 can also function as a sample pedestal, and thus a cooling part or heating part for the sample. In this example, cooling is performed using a Peltier element. When Peltier cooling is used, overwhelming throughput can be realized. Cooling with liquid nitrogen takes a long time before and after observation, taking one hour to cool the temperature, another hour for the temperature to stabilize, and another hour to return to room temperature after observation. However, Peltier cooling simply passes an electric current through it, and can cool down to -100 degrees in 3 minutes and to room temperature in 1 minute, making it possible to dramatically increase the speed of research. The reason why liquid nitrogen was used in the past was that a typical Peltier cooling stage could only cool down to -50 degrees. At -50 degrees, damage from electron beams and focused ion beams could not be reduced, and cooling to -80 to -100 degrees was necessary, so even if one wanted to use Peltier cooling, the only option was to use liquid nitrogen type cooling. However, surprisingly, with this invention, it is now possible to achieve -100 degrees with the Peltier cooling method.

[0062] 53 is an attachment mounting device or an electrode. When it is an attachment mounting device, the content of FIG. 1 described above can be cited as an example. The attachment mounting device and the electrode can be used in combination, or the electrode alone can be used. The electrode can be attached in the electrode shape required by the user, and its shape, arrangement, etc. are not limited. In FIG. 3, four electrodes, etc. are shown, but the number of electrodes can be one or more. It is possible to customize the way of applying electricity required by researchers, etc.

[0063] Also, 54 is a first valve, for example, it can be automatically exhausted during vacuum. Inside the glove box, by filling it with Ar gas etc. and taking it to the SEM and making the SEM vacuum and opening the lid, non-exposure to the atmosphere is realized. However, if the shutter is suddenly opened, a large amount of argon may flow into the SEM and the SEM may break down. Therefore, by providing a valve that can be automatically exhausted, for example, a check valve, a differential pressure is generated between the SEM and the stage chamber, and the valve is released by this differential pressure, so that the chamber can be made vacuum.

[0064] 55 is a second valve, for example, it can be a valve whose opening and closing degree can be adjusted. Contrary to the above-described one, when the stage is transferred from the SEM to the glove box, the chamber of the stage is vacuum, so the second valve 55 has a function as an on-off valve that replaces the vacuum with argon more slowly inside the glove box.

[0065] Next, FIG. 4 is a top view of a stage with a shutter function according to an embodiment of the present invention. In FIG. 4, 50 is a shutter, 51 is a motor, 52 is a sample pedestal (with a cooling part below if any), 54 is a first valve, 55 is a second valve, 60 is a shutter opening / closing screw, and 61 is a gear for connecting the opening / closing lid, respectively. For the shutter 50, the motor 51, the sample pedestal (with a cooling part below if any) 52, the first valve 54, and the second valve 55, the above description can be referred to. 60 is a shutter opening / closing screw. When the motor 51 rotates, the shutter opening / closing screw 60 rotates, and the shutter advances forward so as to seal the inside of the stage. In this example, the rotation of the motor is utilized for the opening / closing movement of the shutter using the gear 61 for connecting the opening / closing lid.

[0066] Next, FIG. 5 is a side cross-sectional view of a stage with a shutter function according to an embodiment of the present invention. In FIG. 5, 70 is a rotating shaft, 71 is a seal assisting part, 72 is a shutter, and 73 is a shutter opening / closing screw, respectively. In this example, a screw is cut on the rotating shaft 70, and a screw that meshes with the corresponding screw is cut on the shutter opening / closing screw 73. When the rotating shaft 70 is rotated by a motor, the rotational movement is also transmitted to the shutter opening / closing screw 73, and according to the rotation, the shutter operates in the right direction in FIG. 5. A seal part, for example, an O-ring, is arranged on the back side of the shutter 72, and when the shutter closes, it is configured to be able to block the atmosphere between the inside and outside of the stage. The seal assisting part 71 is, in this example, a tapered part installed on the side surface of the shutter. When the shutter closes, the guide pin bites into the tapered part 71 and can press the lid (the lid of the stage, the shutter) against the base (the stage body). Thereby, it becomes possible to further utilize the O-ring for sealing. Note that the seal is provided on the shutter side, but it may also be provided on the stage side.

[0067] Next, FIG. 6 is a side view of a stage with a shutter function according to an embodiment of the present invention. In FIG. 6, 80 indicates a guide rail, 81 indicates a guide pin, and 82 indicates a tapered portion. According to the opening and closing movement of the shutter, the guide pin 81 can move along the guide rail. The tapered portion of 82 is tapered, and in the final stage of closing the shutter, a downward force is applied to the lid (the upper part of the stage, the shutter) with the guide pin 81 to hold down the lid so that the O-ring works on the sealing surface. The entire lid can be firmly pressed against the sealing surface by the guide pins 81 and the tapered portions 82 on both sides. According to this structure, a compact atmosphere blocking function can be imparted.

[0068] Next, FIG. 7 is a side cross-sectional view of a stage with a shutter function according to an embodiment of the present invention. In FIG. 7, 90 indicates a first valve, and 91 indicates a feed-through portion. For the first valve 90, reference can be made to the above description. In the present invention, the position of the field-through portion is not particularly limited. With the field-through portion, for example, it is also possible to observe a sample while applying a voltage.

[0069] Next, FIG. 8 is a five-sided view of a stage with a shutter function according to an embodiment of the present invention. FIGS. 8(a) and (e) are side views of a stage with a shutter function according to an embodiment of the present invention. FIG. 8(c) is a top view of a stage with a shutter function according to an embodiment of the present invention. FIG. 8(b) is a front view of a stage with a shutter function according to an embodiment of the present invention. FIG. 8(d) is a rear view of a stage with a shutter function according to an embodiment of the present invention.

[0070] Next, FIG. 9 is a perspective view of a stage with a shutter function according to an embodiment of the present invention. In FIG. 9, 50 indicates a shutter, 51 indicates a motor, 52 indicates a sample pedestal (cooling part below if any), and 53 indicates an attachment mounting device or an electrode. These can be referred to the description in FIG. 3.

[0071] Next, FIG. 10 is a diagram showing a system of an example cooling SEM stage in one embodiment of the present invention. In FIG. 10, 100 is a temperature control controller, 101 is a feedthrough, and 102 is a refrigerant supply device, respectively. The temperature control controller 100 has a role of controlling the temperature inside the stage. The feedthrough 101 is a component for passing electricity, temperature measurement, and cooling water in a vacuum. The refrigerant supply device 102 is a device capable of sending refrigerant without vibration.

[0072] Thus, according to the stage of the present invention, by providing the stage with a shutter function, it is possible to form a structure in which electrodes can also be arranged as long as it has a structure capable of independent vacuum transfer, and it is possible to observe while flowing electricity through the battery, which has an advantageous effect. In particular, in the mode using Peltier cooling, it has been found that speedy experiments can be performed.

Industrial Applicability

[0073] The stage can be transferred under vacuum or the like, and in-situ observation can be performed even under cooling, and it is applicable in a wide range of technical fields.

Explanation of Reference Numerals

[0074] 1 Sample pedestal 2 Attachment mounting device or electrode 3 Thermoelectric element (when a thermoelectric element is required) 4 Heat dissipation member 5 Cooling unit 21 Metal on the hot side (mainly Cu) 22 Ceramic substrate (mainly alumina) 23 Heat dissipation surface 24 N-type semiconductor 25 P-type semiconductor 26 Electric wire 27 Power supply 28 Heat absorption 29 Conduction band of N-type semiconductor 30 Heat dissipation 31 Plus side 32 Heat absorption side 33 Valence band 34 Heat dissipation side 35 Minus side 36 Cold side metal (mainly Cu) 37 Cold side metal (mainly Cu) 38 Electron 39 Hole 40 Conduction band of P-type semiconductor 50 Shutter 51 Motor 52 Sample pedestal (cooling part below if any) 53 Attachment mounting device or electrode 54 First valve 55 Second valve 60 Shutter opening / closing screw 61 Opening / closing lid connecting gear 70 Rotating shaft 71 Seal assisting part 72 Shutter 73 Shutter opening / closing screw 80 Guide rail 81 Guide pin 82 Taper part 90 First valve 91 Feed-through part 100 Temperature control controller 101 Feed-through 102 Refrigerant supply device

Claims

1. A stage, comprising: a sample pedestal for mounting a sample; a shutter function capable of blocking the atmosphere inside and outside the stage; and a seal part.

2. The stage according to claim 1, further comprising a first valve capable of automatic exhaust.

3. The stage according to claim 1 or 2, further comprising a second valve whose opening / closing degree can be adjusted.

4. The stage according to any one of claims 1 to 3, further comprising a motor capable of opening and closing the shutter of the shutter function.

5. The stage according to any one of claims 1 to 4, further comprising a feed-through part.

6. The stage according to any one of claims 1 to 5, further comprising an electrode part.

7. The stage according to any one of claims 1 to 5, wherein the sample pedestal is provided with a device for attaching an attachment.

8. The stage according to any one of claims 1 to 6, further comprising a cooling part.

9. The stage according to claim 7, comprising a thermoelectric element installed in proximity to the cooling part.

10. The stage according to any one of claims 6 to 8, wherein the device for attaching an attachment is a screw hole or a clamp.

11. The stage according to claim 9 or 10, wherein the thermoelectric element is a thermoelectric element utilizing at least one effect selected from the Peltier effect and the Thomson effect.

12. The stage according to any one of claims 9 to 11, wherein the heat dissipation side of the thermoelectric element is in contact with the cooling part.

13. The stage according to any one of claims 8 to 12, wherein the cooling part is composed of at least one of a solid refrigerant, a liquid refrigerant, and a gas refrigerant.

14. The stage according to any one of claims 9 to 13, wherein the sample pedestal and the thermoelectric element are in contact with each other.

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