JP2008293773A - Charged particle beam apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a charged particle beam apparatus in which an O ring of a vacuum partition valve is hardly deteriorated in the charged particle beam apparatus which has a first wall in which a first hole to emit a charged particle beam generated in a charged particle beam generating source is formed and a valve plate which is arranged outside the first wall and on which the O ring capable of contacting with the outside face of the first wall is installed, and has a vacuum sluice valve which holds the inside of the first hole in a vacuum when the O ring contacts with the surrounding of the opening of the first hole outside the first wall and the valve plate closes the first hole of the first wall. <P>SOLUTION: A shielding means (case 211, shield plate 221) 200 to shield scattering electrons, reflecting electrons, X-rays by charged particle beam B is installed between a first hole 103 of the first wall 101 and a valve plate 113 of the vacuum sluice valve 111 in an open state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a charged particle beam apparatus such as an electron microscope and an electron beam exposure apparatus, and more specifically, a first wall in which a first hole from which a charged particle beam generated by a charged particle beam generation source is emitted is formed. A valve plate disposed outside the first wall and provided with an O-ring capable of contacting the outer surface of the first wall, wherein the O-ring is formed on the outer surface of the first wall. A closed state in which the valve plate is pressed around the opening of the first hole and the valve plate closes the first hole of the first wall has a vacuum gate valve that holds the inside of the first hole in a vacuum. The present invention relates to a particle beam apparatus.

In a charged particle beam apparatus such as an electron microscope or an electron beam exposure apparatus, a charged particle beam (hereinafter referred to as an electron beam) emitted from a charged particle beam generation source is reduced and deflected on an electron beam path. In addition, a vacuum gate valve is incorporated. During maintenance, the vacuum gate valve is closed to keep the charged particle beam generation source side in a vacuum state (see, for example, Patent Documents 1, 2, and 3).

An example of such a vacuum gate valve will be described with reference to FIGS. FIG. 5 shows the vacuum gate valve in an open state, and FIG. 6 shows the vacuum gate valve in a closed state.
In these drawings, reference numeral 1 denotes a first wall provided in a lens barrel and formed with a first hole 3 from which an electron beam B generated by a charged particle beam generation source is emitted. The first wall 1 and the second wall 5 are provided so as to face each other through a space. A second hole 7 is formed in the second wall 5 so as to face the first hole 3 and into which the electron beam B emitted from the first hole 3 is incident.

A vacuum gate valve 11 is provided in the space between the first wall 1 and the second wall 5.
The vacuum gate valve 11 has a base 15 that can move on the surface of the second wall 5 facing the first wall 1. A valve plate 13 is disposed on one end side of the surface of the base 15 facing the first wall 1. An O-ring 18 that can contact the outer surface of the first wall 1 is provided on the surface of the valve plate 13 that faces the first wall 1. The diameter of the O-ring 18 is set larger than the diameter of the first hole 3 so as to be able to press around the opening of the first hole 3 on the outer surface of the first wall 1.

  A bracket 14 is provided on the other end side of the surface of the base 15 facing the first wall 1. A drive shaft 17 such as a spindle of an air cylinder (not shown) is connected to the bracket 14 using a pin 16. Accordingly, by driving the drive source, in FIG. 5 where the vacuum gate valve 11 is in the open state, the drive shaft 17 moves in the direction of arrow A, and the vacuum gate valve 11 moves to the closed state shown in FIG. In FIG. 6 in which the gate valve 11 is closed, the drive shaft 17 moves in the direction of arrow C, and the vacuum gate valve 11 is moved to the open state shown in FIG.

  One end of the first link 19 is rotatably attached to the base 15, and the other end of the link 19 is rotatably attached to one end of the valve plate 13. Further, one end of the second link 21 is rotatably attached to the base 15, and the other end of the link 21 is rotatably attached to the other end of the valve plate 13. Therefore, the base 15, the first link 19, the valve plate 13, and the second link 21 constitute a four-bar rotation mechanism, and the valve plate 13 can be moved up and down with respect to the base 15. Yes. That is, the valve plate 13 can approach / separate from the first wall 1. The valve plate 13 is urged in the direction in which it is stacked on the base 15 by a spring 23 as an urging means whose one end abuts on the bracket 14 and whose other end abuts on the valve plate 13.

On the second wall 5 side, a stopper 25 that abuts on the valve plate 13 of the vacuum gate valve 1 that moves toward the open state is provided.
Here, the operation of the vacuum gate valve 1 configured as described above will be described.

When the vacuum gate valve 1 shown in FIG. 5 is in the open state, the drive shaft 17 is driven in the direction of arrow A, and the base 15 moves in the direction of arrow A, that is, in the closed state, the valve plate 13 contacts the stopper 25. . Then, as shown in FIG. 6, the valve plate 13 rises against the urging force of the spring 23, and the O-ring 18 of the valve plate 13 is open to the opening of the first hole 3 on the outer surface of the first wall 1. The valve plate 13 is in a closed state in which the valve plate 13 closes the first hole 3 of the first wall 1 by pressing around.
Japanese Utility Model Publication No. 62-33157 JP-A-8-195180 Japanese Utility Model Publication No. 62-15761

  When the vacuum gate valve 11 shown in FIG. 5 is in the open state, the O-ring 18 of the valve plate 13 is exposed to vacuum at a position slightly away from the electron beam B as shown in FIG. There are scattered electrons, reflected electrons, X-rays, and the like in the path of the electron beam B. When these hit the O-ring 18, the O-ring 18 deteriorates, and there is a problem that the vacuum cannot be sealed due to cracks.

  The present invention has been made in view of the above problems, and an object thereof is to provide a charged particle beam apparatus in which an O-ring of a vacuum gate valve is unlikely to deteriorate.

  According to a first aspect of the present invention for solving the above-mentioned problems, a first wall in which a first hole from which a charged particle beam generated by a charged particle beam generation source is emitted is formed, and the first wall is disposed outside the first wall. And a valve plate provided with an O-ring capable of coming into contact with the outer surface of the first wall, the O-ring being pushed around the opening of the first hole on the outer surface of the first wall. In the charged particle beam apparatus, the closed state in which the valve plate is in contact with and closes the first hole of the first wall is a vacuum gate valve that holds the inside of the first hole in a vacuum state. A charged particle beam characterized in that shielding means for blocking scattered electrons, reflected electrons, and X-rays due to the charged particle beam is provided between the first hole of the vacuum valve and the valve plate of the vacuum gate valve in the open state. Device.

  According to a second aspect of the present invention, the valve plate of the vacuum gate valve moves along the outer surface of the first wall, and the shielding means can accommodate the valve plate in the open state. A case in which an opening is formed on the hole side; a shielding plate that is provided in the opening and opens and closes the opening; and a first urging unit that urges the shielding plate in a direction to close the opening. The charged particle beam apparatus according to claim 1.

  According to a third aspect of the present invention, the valve plate of the vacuum gate valve moves along the outer surface of the first wall, and the shielding means is in an open state with the first hole of the first wall. Between the valve plate of the vacuum gate valve and between the open position where the movement of the valve plate in the direction of the first hole is not restricted and the shielding position facing the front surface of the valve plate in the closed state The charged particle according to claim 1, further comprising: a shielding plate that can be moved at a time, and a second urging means that urges the shielding plate in a direction to contact the front surface of the valve plate in the open state. It is a beam device.

  According to a fourth aspect of the present invention, there is provided a second hole that faces the first wall through a space, faces the first hole, and enters the charged particle beam emitted from the first hole. A second wall formed; and the vacuum gate valve is movable on a surface of the second wall facing the first wall, and the valve is disposed on the surface facing the first wall. A base on which a plate is disposed, a first link having one end rotatably attached to the base and the other end rotatably attached to one end of the valve plate; and one end attached to the base And a second link having the other end rotatably attached to the other end of the valve plate, and a bias for biasing the valve body in the direction of being stacked on the base. And a stopper provided on the second wall side and abutting against the valve plate moving toward the closed state. A charged particle beam device according to any one of claims 1 to 3, wherein.

  According to the invention according to claim 1-4, between the first hole of the first wall and the valve plate of the vacuum gate valve in the open state, scattered electrons, reflected electrons by the charged particle beam, By providing the shielding means for blocking X-rays, the O-ring is unlikely to deteriorate.

  A charged particle beam apparatus according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a view for explaining the periphery of the vacuum gate valve in the open state of the charged particle beam apparatus of this embodiment, FIG. 2 is a view for explaining the periphery of the vacuum gate valve of FIG. 1 in the closed state, and FIG. FIG. 4 is a cross-sectional view taken along a cutting line DD in FIG. 1.

  In FIGS. 1 and 2, reference numeral 101 denotes a first wall provided in a lens barrel and having a first hole 103 through which an electron beam B generated by a charged particle beam generation source is emitted. The first wall 101 and the second wall 105 are provided so as to face each other through a space. A second hole 107 is formed in the second wall 105 so as to face the first hole 103 and into which the electron beam B emitted from the first hole 103 is incident.

A vacuum gate valve 111 is provided in the space between the first wall 101 and the second wall 105.
As shown in FIGS. 1 to 3, the vacuum gate valve 111 has a base 115 that can move on the surface of the second wall 105 facing the first wall 101 using five rollers 102. . A valve plate 113 is disposed on one end side of the surface of the base 115 facing the first wall 101. An O-ring 118 that can contact the outer surface of the first wall 101 is provided on the surface of the valve plate 113 that faces the first wall 101. The diameter of the O-ring 118 is set larger than the diameter of the first hole 103 so that it can be pressed around the opening of the first hole 103 on the outer surface of the first wall 101.

  A bracket 114 is provided on the other end side of the surface of the base 115 facing the first wall 101. A drive shaft 117 such as a spindle of an air cylinder (not shown) is connected to the bracket 114 using a pin 116. Therefore, by driving the drive source, in FIG. 1 in which the vacuum gate valve 111 is in the open state, the drive shaft 117 moves in the direction of the arrow A ′, and the vacuum gate valve 111 moves to the closed state shown in FIG. In FIG. 2 where the vacuum gate valve 111 is in the closed state, the drive shaft 117 moves in the direction of the arrow C ′, and the vacuum gate valve 111 moves to the open state shown in FIG.

  As shown in FIGS. 1 and 2, one end of the first link 119 is rotatably attached to the base 115, and the other end of the link 119 is rotatable to one end of the valve plate 113. Is attached. One end of the second link 121 is rotatably attached to the base 115, and the other end of the link 121 is rotatably attached to the other end of the valve plate 113. Therefore, the base 115, the first link 119, the valve plate 113, and the second link 121 constitute a four-bar rotation mechanism, and the valve plate 113 can be moved up and down with respect to the base 15. . That is, the valve plate 113 can approach / separate from the first wall 101. The valve plate 113 is urged in the direction in which it is laminated on the base 115 by a spring 123 as an urging means whose one end abuts on the bracket 114 and the other end abuts on the valve plate 113.

  On the second wall 105 side, a stopper 125 that abuts on the valve plate 113 of the vacuum gate valve 111 that moves toward the open state is provided. As shown in FIG. 3, the stopper 125 is formed with an abutting portion 125 a with which the tip surface of the valve plate 113 can abut.

  1, 2, and 4, scattering by the charged particle beam B between the first hole 103 of the first wall 101 and the valve plate 113 of the vacuum gate valve 111 in the opened state. Shielding means 200 for blocking electrons, reflected electrons, and X-rays is provided.

  The shielding means 200 of this embodiment can accommodate the base 115 and the valve plate 113 in an open state, and includes a case 211 having an opening 201 formed on the first hole 103 side, and a shielding plate 221 that opens and closes the opening 201. It has become.

  As shown in FIG. 4, the case 211 has an approximately oval cross-sectional shape, and includes an upper case 213 and a lower case 215. The shielding plate 221 is provided on the lower case 215 using a hinge 223 so that the shielding plate 221 can be opened and closed. It is urged in a direction to close the opening 201 by a spring (first urging means) (not shown) that is locked to the ring.

Here, the operation of the vacuum gate valve 111 configured as described above will be described.
In the opened vacuum gate valve 111 shown in FIG. 1, the vacuum gate valve 111 is housed in a case 211, and the opening 201 of the case 211 is closed by a shielding plate 221.

  Here, when the drive shaft 117 is driven in the direction of the arrow A ′ and the base 115 moves in the direction of the arrow “A”, that is, in the closed state, the vacuum gate valve 111 pushes the shielding plate 221 in the opening direction and opens the opening 201. To the outside of the case 211.

  Then, the valve plate 113 comes into contact with the contact portion 125 a of the stopper 125. Then, as shown in FIG. 2, the valve plate 113 rises against the urging force of the spring 123, and the O-ring 118 of the valve plate 113 is opened to the opening of the first hole 103 on the outer surface of the first wall 101. The valve plate 113 is in a closed state in which the valve plate 113 closes the first hole 103 of the first wall 101 by pressing around. Even in this state, the roller 102 at the end of the base 115 is on the shielding plate 221 and the shielding plate 221 is in an open state.

  Next, in order to open the closed vacuum gate valve 111 shown in FIG. 2 to the open state shown in FIG. 1, the drive shaft 117 is driven in the direction opposite to the arrow A ′. Then, the vacuum gate valve 111 is accommodated in the case 211, and the opening 201 of the case 211 is closed by the shielding plate 221.

  According to such a configuration, scattered electrons, reflected electrons, and X-rays generated by the electron beam B are generated between the first hole 103 of the first wall 101 and the valve plate 113 of the opened vacuum gate valve 111. By providing the shielding means for shielding, the O-ring 118 is hardly deteriorated.

  The present invention is not limited to the above embodiment. In the above-described embodiment, the case 211 and the shielding plate 221 that opens and closes the opening 201 of the case 211 are configured as the shielding means, but the case may not be provided. That is, an opening that is disposed between the first hole 103 of the first wall 101 and the valve plate 113 of the opened vacuum gate valve 111 and does not restrict movement of the valve plate 113 in the direction of the first hole 103. A shield plate that is movable between the open state and the shield position facing the front surface of the opened valve plate 113, and a second attachment that biases the shield plate in a direction to contact the front surface of the open valve plate 113. You may comprise with a force means.

It is a figure explaining the vacuum gate valve periphery of the open state of the charged particle beam apparatus of a form example. It is a figure explaining the vacuum gate valve periphery of FIG. 1 of a closed state. FIG. 3 is a view in the direction of arrow E with the first wall of FIG. 2 removed. It is sectional drawing in the cutting line DD. It is a figure explaining the surroundings of the vacuum gate valve of the open state of the conventional electron beam apparatus. It is a figure explaining the vacuum gate valve periphery of FIG. 5 of a closed state.

Explanation of symbols

101 first wall 103 first hole 111 vacuum gate valve 200 shielding means 211 case 221 shielding plate

Claims (4)

A first wall formed with a first hole from which a charged particle beam generated by a charged particle beam generation source is emitted;
A valve plate disposed outside the first wall and provided with an O-ring capable of contacting the outer surface of the first wall, the O-ring being the first of the outer surface of the first wall; A closed state in which the valve plate is pressed around the opening of the first hole and the valve plate closes the first hole of the first wall, and a vacuum gate valve that holds the inside of the first hole in a vacuum;
In a charged particle beam device having
A shielding means for blocking scattered electrons, reflected electrons, and X-rays by the charged particle beam is provided between the first hole of the first wall and the valve plate of the vacuum gate valve in the open state. A charged particle beam device. A valve plate of the vacuum gate valve moves along an outer surface of the first wall;
The shielding means is
A case in which the valve plate in an open state can be accommodated and an opening is formed on the first hole side;
A shielding plate provided at the opening and opening and closing the opening;
First urging means for urging the shielding plate in a direction to close the opening;
The charged particle beam apparatus according to claim 1, comprising: A valve plate of the vacuum gate valve moves along an outer surface of the first wall;
The shielding means is
An open position that is disposed between the first hole of the first wall and the valve plate of the vacuum gate valve in an open state and does not restrict movement of the valve plate in the direction of the first hole; A shielding plate movable between a shielding position facing the front surface of the valve plate in a state;
Second urging means for urging the shielding plate in a direction to contact the front surface of the valve plate in the open state;
The charged particle beam apparatus according to claim 1, comprising: A second wall that is opposed to the first wall through a space, is opposed to the first hole, and is formed with a second hole on which the charged particle beam emitted from the first hole is incident; Provided,
The vacuum gate valve is
A base that is movable on a surface of the second wall facing the first wall, and on which the valve plate is disposed on the surface facing the first wall;
A first link having one end rotatably attached to the base and the other end rotatably attached to one end of the valve plate;
A second link having one end rotatably attached to the base and the other end rotatably attached to the other end of the valve plate;
An urging means for urging the valve body in a direction of being stacked on the base;
A stopper provided on the second wall side and abutting on a valve plate moving toward the closed state;
The charged particle beam apparatus according to claim 1, comprising:

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