Patent Publication Number: US-2023139507-A1

Title: Charged particle beam device

Description:
TECHNICAL FIELD 
     The present invention relates to a charged particle beam device, and more particularly to a charged particle beam device including an ion pump. 
     BACKGROUND ART 
     A charged particle beam device such as a scanning electron microscope, a transmission electron microscope, or a semiconductor inspection device is a device that irradiates a charged particle beam generated by a charged particle beam source arranged in an upper portion of a lens barrel onto a sample arranged inside a sample chamber, detects charged particles obtained by this irradiation, and visualizes information on the shape and the composition of the sample. The charged particle beam device can obtain information on the shape and the composition of a sample with high resolution in a range of micrometer, nanometer, or sub-nanometer. Accordingly, the charged particle beam device is currently widely used, for example, in a manufacturing site of semiconductor devices and the like. 
     In the lens barrel of the charged particle beam device, an electron lens is disposed for irradiating a charged particle beam onto a sample or forming an image on the sample, and the like. In recent years, in order to satisfy the request for the high resolution or the high throughput, attempts have been made with respect to a charged particle beam device such that the electronic lenses are formed in multiple stages or adopts the complicated configuration. As a result, a length of the lens barrel has been elongated and has become large-sized. 
     In a charged particle beam device, an ion pump is connected to an area in the vicinity of a charged particle beam source, that is, to an upper portion of a lens barrel. The ion pump maintains the inside of the lens barrel in an ultra-high vacuum thus preventing the contamination of the charged particle beam source. In many cases, the ion pump is connected to the upper portion of the lens barrel in a cantilever manner. That is, the ion pump is supported by the lens barrel in a state where only one end of the ion pump is connected to the lens barrel. Therefore, when a reaction force generated when a stage that moves a sample is driven acts on a sample chamber, the natural vibration of the ion pump is excited by way of the lens barrel. 
     The ion pump is formed of components including a magnet. Therefore, in the charged particle beam device, a charged particle beam is shaken by the fluctuation of a magnetic field accompanying the natural vibration of the ion pump. As a result, the quality of an observation image is deteriorated. During a period in which the quality of an observation image is deteriorated to an extent that the observation is affected, it is necessary to interrupt the observation. As a result, the throughput is decreased. To increase the throughput, it is necessary to quickly attenuate the natural vibration of the ion pump immediately after the stage is driven. 
     Patent Literature 1 describes an example of a charged particle beam device capable of attenuating the natural vibration of an ion pump. In the charged particle beam device described in Patent Literature 1, a vibration absorber that includes a viscoelastic sheet is disposed between a frame fixed to a sample chamber and an ion pump connected to a lens barrel. With such a configuration, the natural vibration of the ion pump is attenuated within a short time. 
     Patent Literature 2 describes a charged particle beam device that includes a damping member. One end of the damping member is fixed to a sample chamber, and the other end of the damping member is fixed to a lens barrel. The damping member includes a viscoelastic sheet. With such a configuration, it is possible to suppresses the inclination of the lens barrel, and the vibration of the lens barrel in a vertical direction. 
     Patent Literature 3 describes a charged particle beam device that includes a plurality of lens barrels. The charged particle beam device also includes a connection member having one end that is attached to one lens barrel and the other end that is attached to another lens barrel. The connection member includes a viscoelastic sheet. With such a configuration, it is possible to suppress the vibration of the plurality of lens barrels. 
     CITATION LIST 
     Patent Literatures 
     PTL 1: Japanese Patent Application Laid-Open No. 2011-003414 
     PTL 2: WO 2011/043391 A 
     PTL 3: Japanese Patent Application Laid-Open No. 2017-152276 
     SUMMARY OF INVENTION 
     Technical Problem 
     In the invention described in Patent Literature 1, in the charged particle beam device, in order to attenuate the natural vibration of the ion pump, the ion pump is supported from the sample chamber using the vibration absorber and the frame. In the charged particle beam device, as described above, due to the formation of the electronic lens in multiple stages and the adoption of the complicate configuration, a length of the lens barrel has been elongated and large-sized. When the lens barrel is elongated, a distance between the ion pump and the sample chamber is increased. Accordingly, in a case where the ion pump is supported from the sample chamber as disclosed in Patent Literature 1, a frame that forms a support body becomes large-sized. When a support body becomes large-sized, the weight of the entire charged particle beam device is increased, and the manufacturing cost is increased. Accordingly, the large-sizing of the support body is not desirable. 
     As disclosed in Patent Literature 2 and Patent Literature 3, in a case where the lens barrel is supported by the member that includes a viscoelastic body, the vibration of the lens barrel can be attenuated. However, the natural vibration of the ion pump that is connected to the lens barrel cannot be attenuated. 
     It is an object of the present invention to provide a charged particle beam device that can attenuate the natural vibration of the ion pump that is connected to the lens barrel regardless of a length of a lens barrel. 
     SOLUTION TO PROBLEM 
     A charged particle beam device according to the present invention includes: a lens barrel that irradiates a charged particle beam to a sample; an ion pump that is connected to the lens barrel, and evacuates an inside of the lens barrel; and a support member having one end connected to the ion pump and the other end connected to the lens barrel. The support member includes a viscoelastic body that is disposed substantially parallel to a central axis of the lens barrel. 
     Advantageous Effects of Invention 
     The present invention provides a charged particle beam device capable of attenuating natural vibration of an ion pump which is connected to a lens barrel regardless of a length of the lens barrel. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic view illustrating an overall configuration of a conventional charged particle beam device. 
         FIG.  2 A  is a view for explaining directions of modes of natural vibration of an ion pump. 
         FIG.  2 B  is a top plan view of a lens barrel, a flange, a pipe, and the ion pump illustrated in  FIG.  2 A . 
         FIG.  2 C  is a right side view of the lens barrel, the flange, the pipe, and the ion pump illustrated in  FIG.  2 A . 
         FIG.  2 D  is a front view of the lens barrel, the flange, the pipe, and the ion pump illustrated in  FIG.  2 A . 
         FIG.  3    is a schematic view illustrating an overall configuration of a charged particle beam device according to an embodiment 1 of the present invention. 
         FIG.  4    is a view illustrating an example of a configuration of a laminated structural body. 
         FIG.  5 A  is an exploded view of a support member that includes the laminated structural body. 
         FIG.  5 B  is a view illustrating the lens barrel to which the support member that includes the laminated structural body is connected and the ion pump. 
         FIG.  6    is a schematic view illustrating an overall configuration of a charged particle beam device according an embodiment 2 of the present invention. 
         FIG.  7    is a schematic view illustrating the configuration of the charged particle beam device according to the embodiment 2 of the present invention in which a support member includes one viscoelastic body. 
         FIG.  8 A  is a perspective view illustrating a configuration in which a first lens barrel side support body is connected to a plurality of portions of a lens barrel of the charged particle beam device according to the embodiment 2 of the present invention. 
         FIG.  8 B  is a cross-sectional view illustrating a configuration in which the first lens barrel side support body is connected to the plurality of portions of the lens barrel of the charged particle beam device according to the embodiment  2  of the present invention. 
         FIG.  9    is a schematic view illustrating a support member and a lens barrel of a charged particle beam device according to an embodiment 3 of the present invention. 
         FIG.  10 A  is a view for explaining natural vibration of an ion pump in a configuration of a charged particle beam device in which two ion pumps are connected to a lens barrel side by side in a z direction, and these two ion pumps are connected to each other by a connecting member. 
         FIG.  10 B  is a top plan view of a lens barrel, a flange, a pipe, a first ion pump, a second ion pump, and the connecting member illustrated in  FIG.  10 A . 
         FIG.  10 C  is a right side view of the lens barrel, the flange, the pipe, the first ion pump, the second ion pump, and the connecting member illustrated in  FIG.  10 A . 
         FIG.  10 D  is a front view of the lens barrel, the flange, the pipe, the first ion pump, the second ion pump, and the connecting member illustrated in  FIG.  10 A . 
         FIG.  11    is a perspective view illustrating a lens barrel, a first ion pump, and a second ion pump of a charged particle beam device according to an embodiment  4  of the present invention. 
         FIG.  12 A  is a view illustrating a configuration of the charged particle beam device illustrated in  FIG.  11    in which a viscoelastic body  118 D is not provided. 
         FIG.  12 B  is a view illustrating a configuration of the charged particle beam device illustrated in  FIG.  11    in which a viscoelastic body  118 A is not provided. 
         FIG.  13 A  is a perspective view illustrating a configuration of the charged particle beam device according to the embodiment  4  of the present invention in which a second support member is directly connected to the lens barrel. 
         FIG.  13 B  is a cross-sectional view illustrating a configuration of the charged particle beam device according to the embodiment 4 of the present invention in which the second support member is directly connected to the lens barrel. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     A charged particle beam device according to the present invention includes: a lens barrel that irradiates a charged particle beam to a sample; an ion pump that is connected to the lens barrel; and a support member that is connected to the ion pump. The support member includes a viscoelastic body that is connected to the ion pump and the lens barrel and is disposed substantially parallel to a central axis of the lens barrel. In the charged particle beam device according to the present invention, it is unnecessary to support the ion pump from the sample chamber. Accordingly, it is possible to attenuate the natural vibration of the ion pump within a short time regardless of a length of the lens barrel. Therefore, the charged particle beam device according to the present invention can acquire a high-resolution observation image at a high speed without increasing the size of the support member of the ion pump. Accordingly, it is possible to enhance the throughput. 
     First, a conventional charged particle beam device is described. In the charged particle beam device, a charged particle beam that is irradiated to a sample is an electron beam or an ion beam. Hereinafter, as an example, a charged particle beam device that irradiates an electron beam to a sample is described. 
       FIG.  1    is a schematic view illustrating an overall configuration of a conventional charged particle beam device  100 . The conventional charged particle beam device  100  includes a lens barrel  101 , an ion pump  104 , a sample chamber  109 , and a stage  110 . 
     An electron gun  105  is disposed in an upper portion of the lens barrel  101 , and an electron beam  106  irradiated from the electron gun  105  is focused by electron lenses  107 . The central axis of the lens barrel  101  is referred to as a lens barrel central axis  114 . A direction parallel to the lens barrel central axis  114  is a vertical direction. 
     The ion pump  104  is connected to the upper portion of the lens barrel  101  in a cantilever manner (that is, only one end of the ion pump  104  being supported by the lens barrel  101 ) by way of a pipe  103  and a flange  102 . The ion pump  104  maintains the upper portion of the lens barrel  101  in an ultrahigh vacuum state. 
     The sample chamber  109  is evacuated to a vacuum by a turbo molecular pump  111  and a dry pump  112 , and a sample  108  that is an object to be observed is disposed in the sample chamber  109 . The sample chamber  109  is supported on an anti-vibration mount  113  and so that the sample chamber  109  is insulated from floor vibration. 
     The stage  110  is disposed in the sample chamber  109 . The stage  110  is driven so as to move the sample  108 . The sample  108  is placed on the stage  110  at the time of observation. 
     The electron beam  106  is focused as an electron spot on the sample  108  by the electron lenses  107 . During a period in which the sample  108  is observed, the electron spot moves on the sample  108  as a probe by operating a scanning coil (not illustrated). A signal (electron) generated at this time of the operation is converted into an electric signal by a detector (not illustrated). The signal is combined with the coordinates of the electronic spot, and the signal is visualized as information on the shape and the composition of the sample  108 . 
     In the description made hereinafter, in  FIG.  1   , a direction in which the ion pump  104  is connected to the lens barrel  101  as viewed from the lens barrel  101  is defined as an x direction, a direction that is orthogonal to the x direction and is orthogonal to the lens barrel central axis  114  is defined as a y direction, and a direction (vertical direction) that is parallel to the lens barrel central axis  114  is defined as a z direction. Further, the rotation directions around the x axis, the y axis, and the z axis are represented by θx, θy, and θz, respectively. Furthermore, the ion pump  104  is treated as a hexahedron. In this case, a surface of the ion pump  104  that is disposed on a side opposite to a surface of the ion pump  104  and faces the flange  102  and the lens barrel  101  to which the pipe  103  is connected is referred to as a mounting surface  115 . The mounting surface  115  of the ion pump  104  is disposed parallel to the yz plane. 
     The xy plane is a plane perpendicular to the z direction, that is, a plane perpendicular to the lens barrel central axis  114  (vertical direction). The yz plane is a plane perpendicular to the x direction, that is, a plane perpendicular to the direction in which the ion pump  104  is connected as viewed from the lens barrel  101 . The zx plane is a plane perpendicular to the y direction, that is, a plane parallel to the x direction and the z direction. 
       FIG.  2 A  is a view for explaining directions of modes of natural vibration of the ion pump  104 . Experiments and an analysis have revealed that in a case where a reaction force that is generated when the stage  110  is driven acts on the sample chamber  109 , the reaction force is transmitted to the ion pump  104  through the lens barrel  101 , the flange  102 , and the pipe  103  so that the natural vibration of the ion pump  104  is excited in the θx, θy, and θz directions. The mode of the natural vibration of the ion pump  104  in the θx direction is a mode in which the ion pump  104  rotates about the x axis using the pipe  103  as the central. The mode of the natural vibration of the ion pump  104  in the θy direction is a mode in which the ion pump  104  rotates about the y axis using the connection portion between the pipe  103  and the ion pump  104  as the central. The mode of the natural vibration of the ion pump  104  in the θz direction is a mode in which the ion pump  104  rotates about the z axis using the connection portion between the pipe  103  and the ion pump  104  as the central. 
       FIG.  2 B ,  FIG.  2 C , and  FIG.  2 D  are a top plan view, a right side view, and a front view, respectively, of the lens barrel  101 , the flange  102 , the pipe  103 , and the ion pump  104  illustrated in  FIG.  2 A  when a zx plane is set as a front surface. As illustrated in  FIG.  2 B , the mode in the θz direction has a component parallel to the xy plane (surface of a sheet on which drawings are drawn). As illustrated in  FIG.  2 C , the modes in the θx direction, the θy direction, and the θz direction each have a component parallel to the yz plane (surface of a sheet on which the drawing is drawn). As illustrated in  FIG.  2 D , the mode in the θy direction has a component parallel to the zx plane (surface of the sheet on which the drawing is drawn). 
     The ion pump  104  is formed of components including a magnet. Therefore, in the charged particle beam device, the electron beam  106  is shaken by a change in a magnetic field accompanying the vibration of the ion pump  104 . As a result, the quality of an observation image is deteriorated. During a period in which the quality of an observation image is deteriorated to an extent that the observation is affected, it is necessary to interrupt the observation. As a result, the throughput is decreased. In order to enhance the throughput, it is necessary to quickly (for example, within 0.1 seconds) attenuate the natural vibration of the ion pump  104  immediately after the sample  108  is moved to the observation position by driving the stage  110 . 
     Hereinafter, the charged particle beam devices of the embodiments of the present invention will be described with reference to the drawings. In the drawings used in the present specification, the same or corresponding components are denoted by the same symbols, and there may be a case where the repeated description of these components is omitted. 
     In the following embodiment, as an example, a charged particle beam device that irradiates an electron beam  106  to a sample  108  is described. The description is made by taking a semiconductor inspection device as an example of the charged particle beam device. As described previously, the charged particle beam that is irradiated to the sample  108  in the charged particle beam device is an electron beam or an ion beam. Accordingly, the charged particle beam device according to the present invention can also irradiate an ion beam to the sample  108 . In addition, the contents described in the following embodiments are not limited to the configuration for attenuating the natural vibration of an ion pump  104 . That is, the contents can also be applied to a configuration for attenuating the vibration of a device that is mounted on the lens barrel  101  at the time of observing the sample  108  (for example, a detector, an objective diaphragm, a side entry stage, a feedthrough, or a non-evaporable getter pump, or the like). 
     Embodiment 1 
     Hereinafter, a charged particle beam device according to an embodiment 1 of the present invention will be described with reference to the drawings. 
       FIG.  3    is a schematic view illustrating an overall configuration of the charged particle beam device  1  according the present embodiment. The charged particle beam device  1  according to the present embodiment differs from the conventional charged particle beam device  100  illustrated in  FIG.  1    with respect to a point that a support member  117  is connected to a lens barrel  101  and the ion pump  104 . Hereinafter, the points that make the charged particle beam device  1  according to the present embodiment differ from the conventional charged particle beam device  100  are mainly described. 
     Similarly to the conventional charged particle beam device  100 , the lens barrel  101  is a member for irradiating the sample  108  with the charged particle beam (electron beam  106 ). A lens barrel central axis  114  that is a central axis of the lens barrel  101  is parallel to a vertical direction (z direction). 
     One end of the ion pump  104  is connected to an upper portion of the lens barrel  101  by way of a pipe  103  and a flange  102 . The ion pump  104  evacuates the inside of the lens barrel  101  to maintain the inside of the lens barrel  101  in an ultrahigh vacuum state. 
     The support member  117  includes an ion pump-side support body  119 , a lens barrel side support body  120 , and a viscoelastic body  118 . One end the support member  117  is connected to the ion pump  104 , and the other end of the support member  117  is connected to the lens barrel  101 . The support member  117  is provided as a member that attenuates the vibration of the ion pump  104 . The ion pump-side support body  119  is connected to the ion pump  104 . The lens barrel side support body  120  is connected to the lens barrel  101 . The viscoelastic body  118  is disposed substantially parallel to a lens barrel central axis  114 , and is disposed between the ion pump-side support body  119  and the lens barrel side support body  120 . In  FIG.  3   , the viscoelastic body  118  is disposed substantially parallel to a yz plane. 
     One end of the ion pump  104  is connected to the lens barrel  101 , and the other end of the ion pump  104  is connected to the support member  117 . Since the support member  117  is connected to the lens barrel  101 , the other end of the ion pump  104  is connected to the lens barrel  101  by way of the support member  117 . 
     In the charged particle beam device  1  according to the present embodiment, one end of the ion pump  104  is connected to the lens barrel  101 , and the other end of the ion pump  104  is connected to the lens barrel  101  by way of the support member  117  that includes the viscoelastic body  118 . Accordingly, it is possible to attenuate the natural vibration of the ion pump  104  connected to the lens barrel  101  regardless of a length of the lens barrel  101 . 
     As has been described with reference to  FIG.  2 C , the natural vibration of the ion pump  104  that is excited in the θx direction, in the θy direction, and in the θz direction has a component parallel to the yz plane. In the present embodiment, as illustrated in  FIG.  3   , the viscoelastic body  118  is arranged substantially parallel to the yz plane. Accordingly, the viscoelastic body  118  can attenuate the natural vibration of the ion pump  104  excited in any directions consisting of the θx direction, the θy direction, and the θz direction. 
     In order to sufficiently attenuate the natural vibration of the ion pump  104 , it is preferable that the viscoelastic body  118  be formed using a material (for example, a polymer material such as rubber) having a larger attenuation ratio than materials used for forming the lens barrel  101 , the ion pump  104 , the ion pump-side support body  119 , and the lens barrel side support body  120 . 
     The shape of the viscoelastic body  118  is arbitrary, and can be, for example, a sheet shape or a coin shape. To increase the attenuation of the vibration of the ion pump  104 , a thickness of the viscoelastic body  118  may be reduced or an area of the viscoelastic body  118  may be increased. 
     The viscoelastic body  118  is not necessarily disposed in parallel to the lens barrel central axis  114 . For example, provided that an angle between a seat surface of the viscoelastic body  118  (the seat surface that is brought into contact with the ion pump-side support body  119  or the seat surface that is brought into contact with the lens barrel side support body  120 ) and the lens barrel central axis  114  (that is, an angle of the viscoelastic body  118  with respect to the z direction) is 30 degrees or less, the natural vibration of the ion pump  104  can be sufficiently attenuated. 
     The sheet surface of the viscoelastic body  118  is not necessarily parallel to the yz plane. For example, provided that the angle between the sheet surface and the yz plane of the viscoelastic body  118  is 30 degrees or less, the natural vibration of the ion pump  104  can be sufficiently attenuated. 
     When a polymer material is used as the material of the viscoelastic body  118 , the viscoelastic body  118  cannot withstand a high temperature during baking of the ion pump  104 . Therefore, at the time of baking the ion pump  104 , it is necessary to remove the viscoelastic body  118  from the ion pump  104 . To enable easy removal of the viscoelastic body  118  from the ion pump  104 , the viscoelastic body  118  can be replaced with a laminated structural body  121  illustrated in  FIG.  4   , for example. 
       FIG.  4    is a view illustrating an example of a configuration of the laminated structural body  121 . The laminated structural body  121  includes a first support body  122 , a viscoelastic body  123 , and a second support body  124 . The viscoelastic body  123  is disposed between the first support body  122  and the second support body  124 . The laminated structural body  121  may adopt a structure where the first support body  122  and the second support body  124  that sandwich the viscoelastic body  123  therebetween are fixed by an adhesive, a double-sided tape, or the like. 
     As a material used for forming the first support body  122  and a material used for forming the second support body  124 , it is preferable to use a material (for example, metal, ceramic, or the like) that has a smaller attenuation ratio than a material (for example, a polymer material such as rubber) used for forming the viscoelastic body  123 . It is desirable that a thickness of the first support body  122  and a thickness of the second support body  124  be equal to or larger than a thickness of the viscoelastic body  123 . Threaded holes (not illustrated) may be formed in the first support body  122  and the second support body  124  such that these bodies  122 ,  124  can be mounted on other parts. 
       FIG.  5 A  is an exploded view of the support member  117  that includes the laminated structural body  121 .  FIG.  5 B  is a view illustrating the lens barrel  101  and the ion pump  104  to which the support member  117  that includes the laminated structural body  121  is connected. The support member  117  includes an ion pump-side support body  119 , the laminated structural body  121 , and a lens barrel side support body  120 . 
     As illustrated in  FIG.  5 A , the mounting surface  115  of the ion pump  104  and the ion pump-side support body  119  of the support member  117  are connected to each other. The ion pump-side support body  119  and the first support body  122  of the laminated structural body  121  are connected to each other. The laminated structural body  121  is formed by sandwiching the viscoelastic body  123  between the first support body  122  and the second support body  124 . The second support body  124  of the laminated structural body  121  and one end of the lens barrel side support body  120  of the support member  117  are connected to each other. The other end of the lens barrel side support body  120  and the lens barrel  101  are connected to each other. In a step of connecting the support member  117  to the ion pump  104  and the lens barrel  101  to each other, the connection may not be performed in the order described above. 
     By using fixing members  125  such as bolts or screws in performing the above-mentioned connection, the laminated structural body  121  can be easily removed from the ion pump  104  at the time of baking the ion pump  104 . It must be noted that it is unnecessary to use the fixing members  125  for connecting all parts in the above-mentioned connecting operation. Some parts may be connected to each other by a method such as welding or adhesion. 
     With respect to the ion pump  104 , some parts are assembled by welding at the time of manufacture. Accordingly, irregularities in size among ion pumps cannot be avoided. Accordingly, there may be a case where a mounting error of several millimeters may occur with respect to the position of the mounting surface  115  of the ion pump  104 . In view of the above, by forming holes that are formed in the ion pump-side support body  119  and through which the fixing members  125  pass such that each hole has a diameter larger than a diameter of the fixing member  125  or is formed of an elongated hole, the position of the ion pump-side support body  119  on the mounting surface  115  can be moved. Accordingly, the position of the ion pump-side support body  119  with respect to the mounting surface  115  can be adjusted. 
     To suppress a change in a magnetic field fluctuation accompanying the vibration of the support member  117  itself, it is desirable that the support member  117  be partially or entirely made of a non-magnetic material. That is, the ion pump-side support body  119 , the viscoelastic body  118  and the lens barrel side support body  120  that form the support member  117 , the first support body  122 , the viscoelastic body  123  and the second support body  124  that form the laminated structural body  121 , and the fixing members  125  that are used for connection are desirably partially or entirely made of a non-magnetic material. 
     Embodiment 2 
     Hereinafter, a charged particle beam device  1  according to an embodiment 2 of the present invention will be described with reference to the drawings. 
       FIG.  6    is a schematic view illustrating an overall configuration of a charged particle beam device  1  according the present embodiment. The charged particle beam device  1  according to the present embodiment differs from the charged particle beam device  1  according to the embodiment 1 illustrated in  FIG.  3    in the configuration of a support member  117 . Hereinafter, the points that make the charged particle beam device  1  according to the present embodiment 1 differ from the conventional charged particle beam device  1  are mainly described. 
     The support member  117  includes an ion pump-side support body  119 , a viscoelastic body  118 B, a second lens barrel side support body  128 B, a viscoelastic body  118 A, and a first lens barrel side support body  128 A. The support member  117  is a member that is connected to the ion pump  104  and the lens barrel  101 , and attenuates the vibration of the ion pump  104 . 
     The ion pump-side support body  119  is connected to the ion pump  104 . The viscoelastic body  118 B is disposed substantially parallel to a yz plane (that is, substantially parallel to a lens barrel central axis  114 ), and is disposed between an ion pump-side support body  119  and the second lens barrel side support body  128 B. The second lens barrel side support body  128 B connects the viscoelastic body  118 B and the viscoelastic body  118 A to each other. The viscoelastic body  118 A is disposed substantially parallel to an xy plane (that is, substantially orthogonal to a lens barrel central axis  114 ), and is disposed between the second lens barrel side support body  128 B and the first lens barrel side support body  128 A. The first lens barrel side support body  128 A is connected to the lens barrel  101 . 
     In the charged particle beam device  1  according to the present embodiment, one end of the ion pump  104  is connected to the lens barrel  101 , and the other end of the ion pump  104  is connected to the lens barrel  101  by way of the support member  117  that includes the viscoelastic bodies  118 A,  118 B. Accordingly, it is possible to attenuate the natural vibration of the ion pump  104  connected to the lens barrel  101  regardless of a length of the lens barrel  101 . 
     As has been described with reference to  FIG.  2 B , the natural vibration of the ion pump  104  that is excited in the θz direction has a component parallel to the xy plane. In the present embodiment, as illustrated in  FIG.  6   , the viscoelastic body  118 A is arranged substantially parallel to the xy plane. Accordingly, the viscoelastic body  118 A can attenuate the natural vibration of the ion pump  104  excited in the θz direction. In the present embodiment, the viscoelastic body  118 B is arranged substantially parallel to the yz plane. Accordingly, as described in the embodiment 1, the viscoelastic body  118 B can attenuate the natural vibration of the ion pump  104  excited in any directions consisting of the θx direction, the θy direction, and the θz direction. 
     In the charged particle beam device  1  according to the present embodiment, as illustrated in  FIG.  6   , the support member  117  includes the viscoelastic bodies  118 A and  118 B. Accordingly, it is possible to attenuate all the natural vibrations of the ion pump  104  excited in the θx direction, the θy direction, and the θz direction, and particularly, it is possible to greatly attenuate the natural vibration excited in the θz direction. 
     The shapes of the viscoelastic bodies  118 A,  118 B are arbitrary, and can be, for example, a sheet shape or a coin shape. 
     The viscoelastic body  118 A may not necessarily be disposed so as to be orthogonal to the lens barrel central axis  114 , and the viscoelastic body  118 B may not necessarily be disposed in parallel to the lens barrel central axis  114 . For example, provided that an angle between a seat surface of the viscoelastic body  118 A (the seat surface that is brought into contact with the first lens barrel side support body  128 A or the seat surface that is brought into contact with the second lens barrel side support body  128 B) and the lens barrel central axis  114  (that is, an angle of the viscoelastic body  118 A with respect to the z direction) is 30 degrees or less, and an angle between a seat surface of the viscoelastic body  118 B (the surface that is brought into contact with the ion pump-side support body  119  or the surface that is brought into contact with the second lens barrel side support body  128 B) and the lens barrel central axis  114  (that is, an angle of the viscoelastic body  118 B with respect to the z direction) is 30 degrees or less, the natural vibration of the ion pump  104  can be sufficiently attenuated. 
     Further, the sheet surface of the viscoelastic body  118 A is not necessarily parallel to the xy plane, and the sheet surface of the viscoelastic body  118 B is not necessarily parallel to the yz plane. For example, provided that the angle between the sheet surface of the viscoelastic body  118 A and the xy plane is 30 degrees or less, and the angle between the sheet surface of the viscoelastic body  118 B and the yz plane is 30 degrees or less, natural vibration of the ion pump  104  can be sufficiently attenuated. 
     To enable easy removal of the viscoelastic bodies  118 A,  118 B from the ion pump  104 , the viscoelastic bodies  118 A,  118 B can be partially or entirely replaced with a laminated structural body  121  illustrated in  FIG.  4   , for example. 
     Further, the viscoelastic bodies  118 A and  118 B can also be integrally formed of one viscoelastic body. 
       FIG.  7    is a schematic view illustrating the configuration of the charged particle beam device  1  according to the embodiment of the present invention in which a support member  117  includes one viscoelastic body  118 C. The viscoelastic body  118 C is provided on the support member  117  in place of the viscoelastic bodies  118 A,  118 B illustrated in  FIG.  6   . The viscoelastic body  118 C includes a plane substantially parallel to the yz plane and a plane substantially parallel to the xy plane. The plane substantially parallel to the yz plane is located between the ion pump-side support body  119  and the second lens barrel side support body  128 B, and serves as the viscoelastic body  118 B illustrated in  FIG.  6   . The plane substantially parallel to the xy plane is positioned between the second lens barrel side support body  128 B and the first lens barrel side support body  128 A, and serves as the viscoelastic body  118 A illustrated in  FIG.  6   . 
     As illustrated in  FIG.  8 A  and  FIG.  8 B , the first lens barrel side support body  128 A of the support member  117  can also be connected to a plurality of portions of the lens barrel  101 . 
       FIG.  8 A  and  FIG.  8 B  are schematic views illustrating a configuration in which the first lens barrel side support body  128 A is connected to the plurality of portions of the lens barrel  101  in the charged particle beam device  1  according to the embodiment of the present invention.  FIG.  8 A  is a perspective view illustrating the support member  117  and the lens barrel  101 .  FIG.  8 B  is a cross-sectional view illustrating the support member  117  and the lens barrel  101 .  FIGS.  8 A and  8 B  illustrate, as an example, a configuration in which the first lens barrel-side support body  128 A is connected to two portions of the lens barrel  101 . 
     The first lens barrel side support body  128 A includes at least one stay support portion  131 , a plurality of stays  130 , and a plurality of lens barrel connecting portions  129 . The stay support portion  131  is a member where the viscoelastic body  118 A is sandwiched between the stay support portion  131  and the second lens barrel side support body  128 B, and the stay support portion  131  supports the stay  130 . The stay  130  is a holding member that connects the stay support portion  131  and the lens barrel connecting portion  129  to each other, and connects the support member  117  to a plurality of portions of the lens barrel  101 . The lens barrel connecting portion  129  is provided at a plurality of portions in the circumferential direction of the lens barrel  101 , and is a member to which the stay  130  is connected. 
     The first lens barrel side support body  128 A of the support member  117  is connected to a plurality of portions of the lens barrel  101  by a plurality of stays  130 . 
     As illustrated in  FIG.  8 A  and  FIG.  8 B , the configuration is adopted where the first lens barrel side support body  128 A of the support member  117  is connected to the plurality of positions of the lens barrel  101  in the circumferential direction (that is, on the xy plane) of the lens barrel  101 . With such a configuration, compared with the configuration where the support member  117  is connected to the lens barrel  101  at one position as illustrated in  FIG.  5 B , the support rigidity of the ion pump  104  on the xy plane with respect to the lens barrel  101  is increased. Therefore, among the modes of the natural vibration of the ion pump  104 , in particular, a mode excited in the θz direction ( FIG.  2 B ) can be greatly attenuated. 
     Embodiment 3 
     Hereinafter, a charged particle beam device  1  according to an embodiment 3 of the present invention will be described with reference to the drawings. 
       FIG.  9    is a perspective view illustrating a support member  117  and a lens barrel  101  of a charged particle beam device  1  according to an embodiment 3 of the present invention. The charged particle beam device  1  according to the present embodiment differs from the charged particle beam device  1  according to the embodiment 2 illustrated in  FIG.  8 A  and  FIG.  8 B  in the configuration of a support member  117 . As an example of the charged particle beam device  1  according to an embodiment 3,  FIG.  9    illustrates the charged particle beam device  1  where a first lens barrel side support body  128 A of a support member  117  is connected to a plurality of portions of the lens barrel  101  in the same manner as the charged particle beam device  1  illustrated in  FIG.  8 A  and  FIG.  8 B . Hereinafter, the points that make the charged particle beam device  1  according to the present embodiment differ from the conventional charged particle beam device  1  illustrated in  FIG.  8 A  and  FIG.  8 B  are mainly described. 
     The support member  117  includes an ion pump-side support body  119 , a viscoelastic body  118 B, a second lens barrel side support body  128 B, a viscoelastic body  118 A, and a first lens barrel side support body  128 A. The support member  117  is a member that is connected to the ion pump  104  and the lens barrel  101 , and attenuates the vibration of the ion pump  104 . 
     The ion pump-side support body  119  is connected to the ion pump  104 . The viscoelastic bodies  118 B are disposed substantially parallel to a lens barrel central axis  114  and substantially parallel to a zx plane (that is, substantially parallel to a lens barrel central axis  114 ), and is disposed between an ion pump-side support body  119  and the second lens barrel side support body  128 B. In  FIG.  9   , the viscoelastic body  118 B is disposed on each of two side surfaces (zx planes) of the ion pump  104 . The second lens barrel side support body  128 B connects the viscoelastic body  118 B and the viscoelastic body  118 A to each other. In  FIG.  9   , the second lens barrel side support body  128 B is disposed so as to cover the ion pump  104  and the viscoelastic body  118 B. The viscoelastic body  118 A is disposed substantially parallel to an xy plane (that is, substantially orthogonal to a lens barrel central axis  114 ), and is disposed between the second lens barrel side support body  128 B and the first lens barrel side support body  128 A. The first lens barrel side support body  128 A includes a stay support portion  131 , a stay  130 , and a lens barrel connecting portion  129 , and is connected to the lens barrel  101 . 
     In the charged particle beam device  1  according to the present embodiment, one end of the ion pump  104  is connected to the lens barrel  101 , and the other end of the ion pump  104  is connected to the lens barrel  101  by way of the support member  117  that includes the viscoelastic bodies  118 A,  118 B. Accordingly, it is possible to attenuate the natural vibration of the ion pump  104  connected to the lens barrel  101  regardless of a length of the lens barrel  101 . 
     As has been described with reference to  FIG.  2 B , the natural vibration of the ion pump  104  that is excited in the θz direction has a component parallel to the xy plane. As has been described with reference to  FIG.  2 D , the modes that is excited in the θy direction has a component parallel to the zx plane. In the present embodiment, as illustrated in  FIG.  9   , the viscoelastic body  118 A is arranged substantially parallel to the xy plane. Accordingly, the viscoelastic body  118 A can attenuate the natural vibration of the ion pump  104  excited in the θz direction. The viscoelastic bodies  118 B are arranged substantially parallel to the zx plane. Accordingly, the viscoelastic body  118 B can attenuate the natural vibration of the ion pump  104  excited in the θy direction. 
     The shapes of the viscoelastic bodies  118 A,  118 B are arbitrary, and can be, for example, a sheet shape or a coin shape. 
     The viscoelastic body  118 A may not necessarily be disposed so as to be orthogonal to the lens barrel central axis  114 , and the viscoelastic body  118 B may not necessarily be disposed in parallel to the lens barrel central axis  114 . For example, provided that an angle between a seat surface of the viscoelastic body  118 A (the seat surface that is brought into contact with the first lens barrel side support body  128 A or the seat surface that is brought into contact with the second lens barrel side support body  128 B) and the lens barrel central axis  114  (that is, an angle of the viscoelastic body  118 A with respect to the z direction) is 30 degrees or less, and an angle between a seat surface of the viscoelastic body  118 B (the surface that is brought into contact with the ion pump-side support body  119  or the surface that is brought into contact with the second lens barrel side support body  128 B) and the lens barrel central axis  114  (that is, an angle of the viscoelastic body  118 B with respect to the z direction) is 30 degrees or less, the natural vibration of the ion pump  104  can be sufficiently attenuated. 
     Further, the sheet surface of the viscoelastic body  118 A is not necessarily parallel to the xy plane, and the sheet surfaces of the viscoelastic bodies  118 B are not necessarily parallel to the zx plane. For example, provided that the angle between the sheet surface of the viscoelastic body  118 A and the xy plane is 30 degrees or less and the angle between the sheet surface of the viscoelastic body  118 B and the zx plane is 30 degrees or less, the natural vibration of the ion pump  104  can be sufficiently attenuated. 
     To enable easy removal of the viscoelastic bodies  118 A,  118 B from the ion pump  104 , the viscoelastic bodies  118 A,  118 B can be partially or entirely replaced with a laminated structural body  121  illustrated in  FIG.  4   , for example. 
     In the present embodiment ( FIG.  9   ), the viscoelastic body  118 B of the support member  117  is disposed substantially parallel to the zx plane. In the embodiment 2 (for example,  FIG.  8 A  and  FIG.  8 B ), the viscoelastic body  118 B is disposed substantially parallel to a yz plane. That is, in the present embodiment, the direction of the viscoelastic body  118 B differs from that the corresponding direction in embodiment 2. In the configuration of the present embodiment, since the viscoelastic bodies  118 B are disposed on the side surface (zx plane) of the ion pump  104 . Accordingly, it is possible to make a space around the surface (yz plane) of the ion pump  104  opposite to the surface to which the lens barrel  101  is connected. Therefore, in the configuration of the present embodiment, for example, it is possible to easily perform an operation of arranging wiring such as a cable of a baking heater around the ion pump  104 . 
     Embodiment 4 
     Hereinafter, a charged particle beam device  1  according to an embodiment 4 of the present invention will be described with reference to the drawings. 
     In embodiments 1 to 3, the charged particle beam device  1  includes one ion pump  104 . The charged particle beam device  1  according to the present embodiment includes a plurality of ion pumps  104 . Hereinafter, as an example, a configuration in which the charged particle beam device  1  includes two ion pumps  104  (that is, the first ion pump and the second ion pump) is described. 
     In the charged particle beam device  1  such as a semiconductor inspection apparatus, in many cases, the vibration characteristic of the first ion pump and the vibration characteristic of the second ion pump are same or similar to each other. In order to attenuate the natural vibration of the first ion pump and the natural vibration of the second ion pump, the lens barrel  101  and the first ion pump can be connected by the support member  117  described in any one of embodiments 1 to 3, and further, the lens barrel  101  and the second ion pump can be connected by the support member  117  described in any one of embodiments 1 to 3. 
     Hereinafter, another configuration for attenuating the natural vibration of the first ion pump and the second ion pump will be described. 
       FIG.  10 A  is a view for explaining natural vibration of ion pumps in a configuration of a charged particle beam device where the first ion pump  104 A and the second ion pump  104 B are arranged side by side in the z direction and are connected to a lens barrel  101 , and these two ion pumps are connected to each other by a connecting member  133 . It is assumed that the first ion pump  104 A and the second ion pump  104 B have the same or similar vibration characteristics. 
     Experiments and analysis revealed that the charged particle beam device  1  cannot obtain a sufficient damping effect in a case where the first ion pump  104 A and the second ion pump  104 B are merely connected to each other by the connecting member  133 , and the natural vibrations of the ion pumps  104 A and  104 B are excited mainly in the θy direction and the θz direction. 
       FIG.  10 B ,  FIG.  10 C , and  FIG.  10 D  are a top plan view, a right side view, and a front view, respectively, of the lens barrel  101 , a flange  102 , a pipe  103 , the first ion pump  104 A, the second ion pump  104 B and the connecting member  133  illustrated in  FIG.  10 A  when a zx plane is set as a front surface. As illustrated in  FIG.  10 B , among the natural vibrations of the ion pumps  104 A,  104 B, the modes excited in the θz direction has a component parallel to the xy plane (surface of a sheet on which the drawing is drawn). As illustrated in  FIG.  10 C , the modes excited in the θy direction and the θz direction each have a component parallel to the yz plane (surface of a sheet on which the drawing is drawn). As illustrated in  FIG.  10 D , the mode exited in the θy direction has a component parallel to the zx plane (surface of the sheet on which the drawing is drawn). 
       FIG.  11    is a perspective view illustrating a lens barrel  101 , a first ion pump  104 A, and a second ion pump  104 B of the charged particle beam device  1  according to the present embodiment. The charged particle beam device  1  according to the present embodiment differs from the charged particle beam device  1  according to embodiment 3 illustrated in  FIG.  9    with respect to a point that the charged particle beam device  1  includes two ion pumps (first ion pump  104 A and second ion pump  104 B), and the first ion pump  104 A and the second ion pump  104 B are connected to each other by a support member  117  and a second support member  157 . Hereinafter, the points that make the charged particle beam device  1  according to the present embodiment differ from the charged particle beam device  1  illustrated in  FIG.  9    are mainly described. 
     In the charged particle beam device  1  according to the present embodiment, the lens barrel  101  and the first ion pump  104 A are connected to each other by the support member  117  ( FIG.  9   ), and the support member  117  and the second ion pump  104 B are connected to each other by the second support member  157 . That is, the first ion pump  104 A and the second ion pump  104 B are connected to each other by the support member  117  and the second support member  157 . 
     The second support member  157  includes a second ion pump-side support body  136 , a viscoelastic body  118 D and a support body  137 . One end the second support member  157  is connected to the second ion pump  104 B, and the other end of the second support member  157  is connected to the support member  117 . The second support member  157  is provided as a member that attenuates the vibration of the first ion pump  104 A and the second ion pump  104 B. 
     The second ion pump-side support bodies  136  are connected to the second ion pump  104 B. The viscoelastic body  118 D is disposed substantially parallel to the zx plane (that is, substantially parallel to a lens barrel central axis  114 ), and is disposed between a second ion pump-side support body  136  and the support body  137 . The support body  137  is connected to the support member  117 . In  FIG.  11   , the viscoelastic body  118 D and the support body  137  are disposed on each of two side surfaces (zx planes) of the second ion pump  104 B. 
     In the charged particle beam device  1  according to the present embodiment, one end of the first ion pump  104 A is connected to the lens barrel  101 , and the other end of the first ion pump  104 A is connected to the lens barrel  101  by way of the support member  117  including the viscoelastic bodies  118 A and  118 B. One end of the second ion pump  104 B is connected to the lens barrel  101  and the other end of the second ion pump  104 B is connected to the lens barrel  101  by way of the second support member  157  including the viscoelastic body  118 D and the support member  117 . With such a configuration, the present embodiment provides the charged particle beam device  1  capable of attenuating natural vibration of the first ion pump  104 A and the second ion pump  104 B that are connected to the lens barrel  101  regardless of a length of the lens barrel  101 . 
     As described with reference to  FIG.  10 B  to  FIG.  10 D , among the natural vibrations of the ion pumps  104 A and  104 B, the mode excited in the θy direction has at least a component parallel to the zx plane, and the mode excited in the θz direction has at least a component parallel to the xy plane. In the present embodiment, as illustrated in  FIG.  11   , the viscoelastic body  118 A is arranged substantially parallel to the xy plane. Accordingly, the viscoelastic body  118 A can attenuate the natural vibration of the ion pumps  104 A,  104 B excited in the θz direction. In the present embodiment, the viscoelastic bodies  118 B,  118 D are arranged substantially parallel to the zx plane. Accordingly, the viscoelastic body  118 B,  118 D can attenuate the natural vibration of the ion pumps  104 A,  104 B excited in the θy direction. 
     As long as the charged particle beam device  1  according to the present embodiment can attenuate the natural vibration of the ion pumps  104 A and  104 B to such an extent that the observation of the sample  108  is not affected, the charged particle beam device  1  may not include some of the viscoelastic bodies  118 A,  118 B, and  118 D.  FIGS.  12 A and  12 B  illustrate examples of the charged particle beam device  1  having such a configuration. 
       FIG.  12 A  is a view illustrating a configuration of the charged particle beam device  1  illustrated in  FIG.  11    in which the viscoelastic body  118 D is not provided. 
       FIG.  12 B  is a view illustrating a configuration of the charged particle beam device  1  illustrated in  FIG.  11    in which the viscoelastic body  118 A is not provided. 
     In the charged particle beam device  1  according to the present embodiment, the second support member  157  can also be directly connected to the lens barrel  101  in order to largely attenuate the natural vibration excited particularly in the θz direction with respect to both the first ion pump  104 A and the second ion pump  104 B. That is, the second support member  157  may be directly connected to the lens barrel  101  without the support member  117  interposed therebetween. 
       FIG.  13 A  and  FIG.  13 B  are schematic views illustrating a configuration of the charged particle beam device  1  according to the present embodiment in which the second support member  157  is directly connected to the lens barrel  101 .  FIG.  13 A  is a perspective view illustrating the support member  117 , the second support member  157 , and the lens barrel  101 .  FIG.  13 B  is a cross-sectional view illustrating the support member  117 , the second support member  157 , and the lens barrel  101 . 
     As illustrated in  FIG.  13 A  and  FIG.  13 B , the support member  117  connects the lens barrel  101  and the first ion pump  104 A to each other, and the second support member  157  connects the lens barrel  101  and the second ion pump  104 B to each other. The support member  117  and the second support member  157  are connected to each other. 
     The second support member  157  includes a second ion pump-side support body  136 , a viscoelastic body  118 D arranged substantially parallel to the zx plane, a support body  137 , a viscoelastic body  118 E, a stay support portion  139 , a stay  138 , and a lens barrel connecting portion  129 . 
     The viscoelastic body  118 E is disposed substantially parallel to an xy plane (that is, substantially orthogonal to a lens barrel central axis  114 ), and is disposed between the support body  137  and the stay support portion  139 . 
     The stay support portion  139  is a member where the viscoelastic body  118 E is sandwiched between the stay support portion  139  and the support body  137 , and the stay support portion  139  supports the stay  138 . The stay  138  is a strut member that connects the stay support portion  139  and the lens barrel connecting portion  129  to each other, and connects the second support member  157  to a plurality of portions of the lens barrel  101 . The lens barrel connecting portion  129  is provided at a plurality of portions in the circumferential direction of the lens barrel  101 , and is a member to which the stay  138  is connected. That is, the second support member  157  is connected to the lens barrel  101  by the stay  138 . 
     The shapes of the viscoelastic bodies  118 A,  118 B,  118 D,  118 E are arbitrary, and can be, for example, a sheet shape or a coin shape. 
     The viscoelastic body  118 A and the viscoelastic body  118 E may not necessarily be disposed so as to be orthogonal to the lens barrel central axis  114 , and the viscoelastic bodies  118 B and the viscoelastic bodies  118 D may not necessarily be disposed in parallel to the lens barrel central axis  114 . For example, provided that the angle between the sheet surface of the viscoelastic body  118 A and the lens barrel central axis  114  (that is, the angle of the viscoelastic body  118 A with respect to the z direction), the angle between the sheet surface of the viscoelastic body  118 E (the surface that is brought into contact with the support body  137  or the stay support portion  139 ) and the lens barrel central axis  114  (that is, the angle of the viscoelastic body  118 E with respect to the z direction), the angle between the sheet surface of the viscoelastic body  118 B and the lens barrel central axis  114  (that is, the angle of the viscoelastic body  118 B with respect to the z direction), and the angle between the sheet surface of the viscoelastic body  118 D (the surface that is brought into contact with the second ion pump-side support body  136  or the support body  137 ) and the lens barrel central axis  114  (that is, the angle of the viscoelastic body  118  D with respect to the z direction) are each 30 degrees or less, it is possible to sufficiently attenuate the natural vibration of the ion pump  104 . 
     Further, the sheet surface of the viscoelastic body  118 A and the sheet surface of the viscoelastic body  118 E are not necessarily parallel to the xy plane, and the sheet surface of the viscoelastic body  118 B and the sheet surface of the viscoelastic body  118 D are not necessarily parallel to the zx plane. For example, provided that the angle between the sheet surface of the viscoelastic body  118 A and the xy plane, the angle between the sheet surface of the viscoelastic body  118 E and the xy plane, the angle between the sheet surface of the viscoelastic body  118 B and the zx plane, and the angle between the sheet surface of the viscoelastic body  118 D and the zx plane are each 30 degrees or less, the natural vibrations of the ion pumps  104 A and  104 B can be sufficiently attenuated. 
     To enable easy removal of the viscoelastic bodies  118 A,  118 B,  118 D  118 E from the ion pumps  104 A and  104 B, the viscoelastic bodies  118 A,  118 B,  118 D,  118 E can be partially or entirely replaced with a laminated structural body  121  illustrated in  FIG.  4   , for example. 
     To suppress a change in a magnetic field accompanying the vibration of the second support member  157  itself, it is desirable that the second support member  157  be partially or entirely made of a non-magnetic material in the same manner as the support member  117 . 
     In the present embodiment, the charged particle beam device  1  that includes two ion pumps  104 A and  104 B has been described. Even in the charged particle beam device  1  that includes three or more ion pumps  104 , it is possible to attenuate the natural vibration of three or more ion pumps  104  by using the configuration described in the present embodiment or combining the configuration described in the present embodiment with any of the configurations described in embodiments 1 to 3. 
     The present invention is not limited to the above-described embodiments, and includes various modifications of these embodiments. For example, the above-described embodiments have been described in detail for facilitating the understanding of the present invention. However, the present invention is not necessarily limited to the modes that includes all constituent elements described above. 
     Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Further, a part of the configuration of one embodiment can be added to the configuration of another embodiment. In addition, a part of the configuration of each embodiment can be deleted, or another configuration can be added or replaced. 
     REFERENCE SIGNS LIST 
       1  charged particle beam device 
       100  conventional charged particle beam device 
       101  lens barrel 
       102  flange 
       103  pipe 
       104  ion pump 
       104 A first ion pump 
       104 B second ion pump 
       105  electron gun 
       106  electron beam 
       107  electronic lens 
       108  sample 
       109  sample chamber 
       110  stage 
       111  turbo molecular pump 
       112  dry pump 
       113  anti-vibration mount 
       114  lens barrel central axis 
       115  mounting surface 
       117  support member 
       118 ,  118 A,  118 B,  118 C,  118 D,  118 E viscoelastic body 
       119  ion pump side support body 
       120  lens barrel side support body 
       121  laminated structural body 
       122  first support body 
       123  viscoelastic body 
       124  second support body 
       125  fixing member 
       128 A first lens barrel side support body 
       128 B second lens barrel side support body 
       129  lens barrel connecting portion 
       130  stay 
       131  stay support portion 
       133  connecting member 
       136  second ion pump-side support body 
       137  support body 
       138  stay 
       139  stay support portion 
       157  second support member