JP2001085291A - Electron beam exposure equipment - Google Patents

Abstract

(57) [Object] To provide an electron beam exposure apparatus provided with a seal structure capable of rotating a stage at high speed. An electron beam exposure apparatus includes a motor.
And a linear moving mechanism 23 that supports the motor 21 so as to be able to linearly move in the horizontal direction. The stage 17 on which the workpiece 16 is placed is fixed to a motor rotation shaft 22. The electron beam column 9 is arranged above the stage 17. The exposure space 4 is formed in a container 5. The container 5 has a long hole 18 surrounding the moving area of the rotating shaft 22, a bottom wall 6 facing the bottom surface of the stage via a minute gap, and a ceiling wall 7 forming the exposure space 4 together with the bottom wall 6.
It has a peripheral wall 8. The exposure space 4 is provided with a vacuum pump 27
The exposure space 4 is evacuated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electron beam exposure apparatus for exposing a workpiece to an electron beam in a vacuum.

[0002]

2. Description of the Related Art An electron beam exposure apparatus is used for an exposure process of a large-scale integrated circuit (LSI) because it can perform exposure and drawing with higher precision than an optical exposure apparatus.
By the way, since an LSI is composed of a combination of vertical and horizontal linear patterns, a stage on which a sample to be exposed is set is moved in the vertical and horizontal directions (Y and X directions). It has a shaft drive mechanism.

On the other hand, unlike an LSI, an information recording section (track) of an optical disk is constituted by a plurality of concentric patterns or spiral patterns. Therefore, the stage on which the sample to be exposed is set requires a rotary drive mechanism for rotating the stage and a linear drive mechanism for moving the stage from the center of the disk in the radial direction.

FIG. 4 shows an example of a conventional electron beam exposure apparatus having such a rotary drive mechanism and a linear drive mechanism.
As shown in the figure, the electron beam exposure apparatus 51 has an outer container 52. A linear drive mechanism 53 is provided in the outer container 52.
Is arranged. The linear drive mechanism 53 includes the outer container 51
And a movable table 55 supported by the fixed table 54. The movable table 55 can be moved in a specific direction (left-right direction in the drawing).

[0005] The movable table 55 supports the inner container 56. A motor 57 has a rotating shaft 58 inside the inner container 56.
Is fixed upward. Rotary shaft 5 of motor 57
8 projects through an opening 59 formed in the ceiling of the inner container 56 into a space 60 surrounded by the outer container 52 and the inner container 56, and supports a stage 61 disposed in this space 60. I have.

[0006] Above the stage 61, an electron beam column 62 is arranged. The electron beam column 62 has an electron gun 63 for generating an electron beam, and an optical system 64 for guiding the electron beam generated by the electron gun 63. An electron beam 65 transmitted through the optical system 64 is set on the stage 61. It is fixed to the ceiling of the outer container 52 so that an image is formed on a sample (workpiece) 66 to be processed.

In the electron beam exposure apparatus 51 having such a configuration, the space 60 sandwiched between the outer container 52 and the inner container 56 is connected to the vacuum pump 67, and the air in the space 60 is exhausted, and a vacuum is created there. It is formed. On the other hand, since the motor 57 cannot guarantee high-precision rotation by an air bearing in a vacuum, the opening 59 is sealed with a seal 68 around a rotation shaft 58 that passes through the opening 59,
This keeps the inside of the inner container 56 at atmospheric pressure.
As the seal 68, one having a function of a rotary bearing and having durability against vacuum pressure is selected, and a magnetic seal provided with a magnetic fluid is generally used.

[0008]

However, in the electron beam exposure apparatus 51 constructed as described above, when the motor 57 is driven to rotate the rotating shaft 58, the rotating shaft 58 is rotated in accordance with the rotation of the rotating shaft 58. The magnetic fluid of the magnetic seal 68 surrounding the rotary shaft rotates around the rotation shaft 58 and moves outward due to the centrifugal force generated at that time. The movement of the magnetic fluid increases in accordance with the rotation speed (rotation speed) of the rotation shaft 58, and when the rotation shaft 58 rotates at high speed, the magnetic seal 68
The sealing performance of the Therefore, the rotation shaft 58 and the stage 61 cannot be rotated at a high speed, and the exposure length per unit time is limited.

Further, since the linear drive mechanism 53 exists in the vacuum space 60, a structure (for example, grease and bearing structure to be used) necessary for obtaining the linear movement of the linear movement mechanism 53 is required to have vacuum resistance. For this reason, there is a problem that an expensive drive mechanism that can withstand vacuum must be employed.

Accordingly, an object of the present invention is to provide an electron beam exposure apparatus having a seal structure capable of rotating a stage at high speed. Another object of the present invention is to provide an electron beam exposure apparatus that does not require an expensive linear drive mechanism for vacuum durability.

[0011]

In order to achieve the above object, an electron beam exposure apparatus according to the present invention comprises a motor having a rotating shaft extending in a vertical direction and supporting the motor so as to be capable of linearly moving in a horizontal direction. A linear moving mechanism, a stage fixed to a rotating shaft of a motor, on which a workpiece is mounted, an electron beam column arranged above the stage, and a slot surrounding the rotating shaft and a moving region of the rotating shaft. A first wall portion facing the bottom surface of the stage via a minute gap, and an exposure space for projecting an electron beam emitted from the electron beam column onto the workpiece together with the first wall portion above the stage. And a vacuum pump that sucks air in the exposure space to evacuate the exposure space.

According to another aspect of the present invention, there is provided an electron beam exposure apparatus which surrounds a long hole in a surface portion of a stage facing a first wall, a surface portion of a first wall facing a stage, or both surface portions. A continuous groove is formed, and a second vacuum pump for sucking air in the continuous groove is connected.

According to another aspect of the present invention, there is provided an electron beam exposure apparatus which surrounds a long hole in a surface portion of a stage facing a first wall, a surface portion of a first wall facing a stage, or both surface portions. A second continuous groove is formed, and a pressurizing pump for pressurizing the inside of the second continuous groove is connected.

[0014]

FIG. 1 shows an embodiment of an electron beam exposure apparatus 1 according to the present invention. Electron beam exposure equipment 1
Has a frame 3 fixed to a base 2. A container 5 forming an exposure space 4 for exposing an electron beam to a sample (workpiece) is supported on the upper portion of the frame 3. The container 5 includes a bottom wall (first wall portion) 6, a ceiling wall (second wall portion) 7 located above the bottom wall 6 at a predetermined interval, and a bottom wall 6 and a ceiling wall. 7 are formed by a peripheral wall (second wall portion) 8 connecting the peripheral portions thereof to each other, and the exposure space 4 is formed inside these walls. In the drawings, these three wall portions are shown integrally, but it is preferable that these three wall portions are configured as separate portions so that the configuration shown in the assembled state can be obtained. .

The electron beam column 9 has an outer cylinder 10.
The outer cylinder 10 has an electron beam emission port 11 at the lower end. The outer cylinder 10 houses an electron gun 13 for generating an electron beam 12 and an optical system 14 for shaping the generated electron beam and emitting the electron beam from an electron beam exit port 11. Are fixed to the opening 15 formed in the substantially central portion of the exposure space 11 with the emission port 11 positioned in the exposure space 4. The gap between the periphery of the outer cylinder 10 and the opening 15 is sealed by an appropriate means.

A stage 17 on which a sample (workpiece) 16 to which the electron beam 12 emitted from the electron beam column 9 is exposed is placed in the exposure space 4, and is rotatable and horizontal about an axis extending in the vertical direction. It is movably supported in the direction. In order to guarantee such movement of the stage 17, a substantially rectangular through hole (a long hole) 18 is formed in the bottom wall 6. In addition, as shown in FIG.
The major axis 19 and the minor axis 20 are directed in the left-right direction of FIG. 1 and the direction orthogonal thereto. Further, a motor (for example, a spindle motor) 21 is provided below the bottom
The rotation shaft 22 extends in the exposure space 4 through the through-hole 18, and fixedly supports the center of the stage 17. Further, the motor 21 is supported by a linear moving mechanism 23 fixed to the base 2. The linear moving mechanism 23 includes a fixed part 24 and a movable part 25 that moves in a specific horizontal direction (left and right direction in the drawing) with respect to the fixed part 24, and the motor 21 is fixed to the movable part 25. .

In order to evacuate the exposure space 4 in the container 5, for example, an exhaust pipe 26 attached to the peripheral wall 8 is connected to a vacuum pump 27. In order to maintain a stable vacuum in the exposure space 4, the gap 28 between the stage 17 and the bottom wall 6 must be properly sealed. for that reason,
The gap 28 between the stage 17 and the bottom wall 6 is set to an extremely small value (for example, about 5 to 10 μm).

In addition to the above configuration, in the exposure apparatus 1 of the present embodiment, in order to enhance the sealing property of the gap 28, FIGS.
As shown in the figure, two continuous endless grooves 2 surrounding the through holes 18 are formed in the upper surface portion of the bottom wall 6 facing the stage 17.
9 and 30 are formed. In addition, these grooves 29, 3
0 is connected to separate vacuum pumps 33 and 34 via passages 31 and 32 formed in the bottom wall 6.

According to the electron beam exposure apparatus 1 configured as described above, the vacuum pump 27 is driven to evacuate the air in the exposure space 4, and the exposure space 4 It is evacuated until. In addition, vacuum pump 3
3 and 34, the gap 28 between the stage 17 and the bottom wall 6
Is exhausted, and the degree of vacuum in the exposure space 4 is properly maintained.

In this state, the sample 16 on the stage 17 is exposed to the electron beam 12 emitted from the electron beam column 9. The exposure position of the electron beam 12 on the sample 16 moves in the circumferential direction on the upper surface of the sample 16 by the rotation of the motor 21. Further, the motor 21 is continuously or intermittently moved in the horizontal direction by the linear movement mechanism 23 in synchronization with the rotation of the motor 21, and the rotation shaft 22 moves in the region (the rotation shaft movement region) in the through hole 18. Move continuously or intermittently,
The exposure position of the electron beam 12 moves in the radial direction. As a result, a spiral exposure pattern or an exposure pattern composed of a plurality of concentric circles is formed on the upper surface of the sample 16.

In the above description, two continuous grooves 29, 30 are formed in the bottom wall 6, but one or more continuous grooves may be provided. In the above description, the grooves 29 and 30 are endlessly continuous grooves, but may be spiral grooves.
Further, in the above description, the grooves 29 and 30 are formed in the bottom wall 6, but may be formed on the lower surface of the stage 17 facing the bottom wall 6 instead of or in addition to the bottom wall. Also in this case, a suction hole is provided on the upper surface of the opposed bottom wall 6, and air can be sucked from the groove of the stage 17 through the suction hole. Furthermore, in the above description, two grooves 2 are formed in the bottom wall 6.
9 and 30 were formed and air was exhausted from both grooves 29 and 30, respectively. The groove 29 closer to the through hole 18 was connected to a pressure pump, and compressed air supplied from this pressure pump was It is also possible to prevent the bottom wall 6 and the stage 17 from coming into contact with each other and to keep the gap 28 between them constant by spraying from the nozzle 29.

[0022]

As is clear from the above description, according to the electron beam exposure apparatus of the present invention, the periphery of the rotating shaft of the motor can be sealed well. Further, even if the rotation of the rotating shaft and the stage is increased, the sealing property of the exposure space is not affected, so that the sample can be exposed at high speed. Furthermore, since the linear moving mechanism can be arranged under the atmospheric pressure, an inexpensive device that can be used at atmospheric pressure can be used for the linear moving mechanism.

[Brief description of the drawings]

FIG. 1 is a partially cut-away side view of an electron beam exposure apparatus according to the present invention.

FIG. 2 is a plan view showing through holes and grooves formed in the bottom of the exposure container.

FIG. 3 is a cross-sectional view showing a through hole and a groove formed at the bottom of the exposure container.

FIG. 4 is a partially cut-away side view of a conventional electron beam exposure apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electron beam exposure apparatus, 4 ... Exposure space, 5 ... Container, 9
... Electron beam column, 16 ... Sample (workpiece), 17 ...
Stage, 18: through hole, 21: motor, 22: rotating shaft, 23: linear moving mechanism.

Claims (3)

[Claims] 1. A motor having a rotating shaft extending in a vertical direction, a linear moving mechanism for supporting the motor so as to be linearly movable in a horizontal direction, and a stage fixed to the rotating shaft of the motor and for mounting a workpiece. An electron beam column disposed above the stage, a first wall portion having an elongated hole surrounding the rotation axis and a moving area of the rotation axis, and facing a bottom surface of the stage via a minute gap; And a second wall portion that forms an exposure space for projecting the electron beam emitted from the electron beam column onto the workpiece together with the first wall portion above the stage; An electron beam exposure apparatus, comprising: a vacuum pump that sucks air to evacuate the exposure space. 2. A continuous groove surrounding the long hole is formed in a surface portion of the stage facing the first wall, a surface portion of the first wall facing the stage, or a surface portion of both of them. 2. The electron beam exposure apparatus according to claim 1, wherein a second vacuum pump for sucking air in the continuous groove is connected. 3. A second continuous groove surrounding the elongated hole is formed on a surface portion of the stage facing the first wall, a surface portion of the first wall facing the stage, or both surface portions. The electron beam exposure apparatus according to claim 2, wherein a pressurizing pump formed and pressurized in the second continuous groove is connected.