JP3063107B2 - Electrostatic deflection device and method of manufacturing electrostatic deflection device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-precision electrostatic deflection device used in a charged particle beam device such as an electron beam lithography device and an ion beam device, and a method of manufacturing the same. .

[Conventional technology]

As shown in Japanese Patent Publication No. 63-55744, a conventional device of this type includes a hollow insulator having a continuous periphery and a plurality of electrode pieces protruding from the inner surface of the hollow insulator. The space between the electrodes is curved so that the insulator cannot be seen from the beam path through the space between the electrodes.

When processing the space by separating the electrodes,
Wire cut electrical discharge machining is used.

[Problems to be solved by the invention]

In the conventional technology as described above, since the space needs to be curved, the dimensions required for the wire cut electric discharge machining are long, and it is necessary to perform the machining for a long time. Traces remained as a rough surface, and the surface area was large, so that a large amount of gas was emitted, and the inside of the cylinder was easily contaminated when the charged particle beam was emitted.

Furthermore, if the wire cut electric discharge machining is performed in the insulating oil and then the heating baking is performed, there is a problem that the dimensional accuracy is deteriorated due to a difference in an expansion coefficient between the insulator and the metal.
On the other hand, if heating is not performed, there is a problem that a large amount of hydrocarbon is released when the charged particle beam is applied.

[Means to solve the problem]

In order to solve the above problems, in the present invention, a concave groove having a width wider than the space is provided in the cylindrical insulating material supporting the electrode, at the position of the space between the deflecting electrodes in the axial direction. A conductive film having a width wider than the space between the electrodes was provided at the center of the groove, and the conductive film was grounded.

In order to solve the above-mentioned other problems, the surface was previously finished to a smooth surface, and the electrode that had been degassed was assembled using a jig whose surface material was at least different from the electrode, and assembled. Then, after confirming that the accuracy is within the standard, dissolve the jig with chemicals, water, etc., dissolve by heating, carbonize by combustion, or cool by using the difference in thermal expansion or An assembly method of removing by heating was adopted.

[Action]

In the present invention, since the surface of the insulator viewed from the path of the charged particle beam is coated with a thin film of a grounded conductor, the insulator is not charged and does not affect the charged particle beam.

Further, since the space insulating between the electrodes is linear, the surface area is small and the amount of released gas is small.

Furthermore, since final assembly is not performed by wire-cut electric discharge machining, the assembly is performed using a jig.
Since the baking process can also be performed, the degree of vacuum does not deteriorate when mounted inside the envelope.

In the assembly using the conventional jig, there was a problem in that the assembly accuracy was poor because a jig provided with a slight play was used so that the jig could be easily removed.However, the jig was melted with a chemical or the like and melted by heating. By removing the carbonization by combustion or utilizing the difference in thermal expansion, such a play is not required, so that high-precision assembly is possible.

〔Example〕

FIG. 1 is a cross-sectional view of a first embodiment of the present invention, in which a deflection electrode 1a to 1d having a substantially oval cross section and a columnar shape (the longitudinal direction is vertical to the paper surface) is a charged particle beam. A screw corresponding to each electrode is formed on the inner surface of the ceramic cylinder 2 by forming a space between a central portion forming the passage 4 and an adjacent one another.
It is tightened and fixed at 6a to 6d. Semi-circular grooves 3a to 3d having a semicircular cross section are formed in the surface of the ceramic cylinder 2 at the back of each of the spaces 7a to 7d between the electrodes when viewed from the path of the charged particle beam at the center. Have been. Metals 5a to 5d are adhered to the inner peripheral surface of the groove by vapor deposition or the like in a range not in contact with the electrodes 3a to 3d. Width between electrodes (d ₁ )
Since the surface of the ceramic cylinder 2 cannot be seen from the passage 4 of the charged particle beam because of the relationship of <width of the vapor deposition section (d ₂ ) <width of the groove (d ₃ ), the charged surface of the ceramic cylinder 2 is charged. It does not affect. The metal films 5a to 5d are electrodes 3a to
Since there is no contact with 3d, the electrode 3ae3d does not short-circuit. The entire surface of the ceramic cylinder 2 is coated with a metal film 5 (the films 5a to 5d are a part thereof) except where they come into contact with the electrodes 1a to 1d and the tightening screws 6a to 6d (only 6c is shown). It is grounded through the metal fittings for mounting the vessel. The area where the metal film is formed is shown by a broken line in FIG. The above-described grooves 3a to 3d are not limited to those having a semicircular cross-sectional shape, but may have another shape such as a U-shape, a triangular shape, or the like.

FIG. 2 is a diagram showing the second embodiment of the present invention applied to the case of four electrodes. Ceramic cylinder 2 and each electrode 1a-1d
Is processed, subjected to a surface treatment and a baking treatment for degassing, and then assembled.

The shapes of the electrodes 1a to 1d are basically the same as those shown in FIG. 1, but the opposing surfaces of the electrodes 1a to 1d are so formed that a cylindrical space is formed between adjacent electrodes. Is formed with a groove. At the time of assembly, the accuracy in the radial direction of each of the electrodes 1a to 1d can be easily obtained by sufficiently tightening the screws. In order to obtain the accuracy in the θ direction, the cylindrical jigs 8a to 8d
Assembling is performed in cylindrical spaces 70a to 70d formed in 7a to 7d. Here, the surfaces in contact with the jigs 8a to 8d and the electrodes 1a to 1d have high accuracy in the θ direction by finishing both surfaces with high precision. Depending on the electrode material after assembly, it may be better to perform annealing. In order to assemble with high precision, the play between the jigs 8a to 8d and the electrodes 1a to 1d must be eliminated, so that the jigs 8a to 8d cannot be removed as they are. In the present embodiment, a cylindrical space and jigs 8a to 8d
Was made larger than the width of the inter-electrode spaces 7a to 7d, and the jig was immersed in liquid nitrogen, contracted, and removed. In this case, a material having a small expansion coefficient such as Ti was used as the electrode material, and a material having a large expansion coefficient such as Al was used for the jig. As another embodiment, the jigs 8a to 8d are made of an organic substance such as acrylic, removed by dissolution with a solvent, made of rock salt and removed with water, made of a low-melting metal and removed by melting,
It may be made of a metal having a high ionization tendency, such as Al or Mg, and may be dissolved and removed with an acid or alkali. If the deflector is long in the axial direction, it is difficult to exhaust the residual gas in the beam passage. Therefore, if the deflector can be exhausted in the radial direction, the conductance increases. Second
In the figure, holes formed by shifting the screws 6a to 6d in the longitudinal direction
A plurality of ceramic cylinders 10a to 10d were provided. The inside of this hole was also coated with an antistatic metal coating.

FIG. 3 shows a third embodiment of the present invention. The grooves 3a to 3d having a semicircular cross section in FIG. 1 need to be processed inside the insulator (to form a concave portion). This is difficult to process. If the relief portion 12 is provided in the form of a step on the side of the electrode as shown in FIG.

By utilizing the space between the electrodes 1a to 1d and the ceramic cylinder 2 formed by the steps, the metal films 5a to 5d are formed by plating on the surface of the ceramic cylinder 2 facing the inter-electrode spaces 7a to 7d, so that deflection is performed. Metal film 5a grounded to electrodes 1a-1d
5d can be prevented, and the surface of the insulator visible from the beam path can be made of a metal film.

〔The invention's effect〕

According to the present invention, the surface of the insulator is not charged and does not affect the charged particle beam without curving the space between the electrodes.

Since the space between the electrodes does not need to be curved, a reduction in processing time and a reduction in gas emission due to a reduction in surface area are achieved.

According to the invention of claim (2), the jig and the electrode can be assembled with almost no play, so that a highly accurate deflector can be obtained.

In the second embodiment, since it is possible to assemble the components that have been subjected to the surface treatment and the baking process after the component processing, it is not necessary to perform the heat treatment after the assembly.

Further, according to the second embodiment and the third embodiment, the exhaust conductance from the passage of the charged particle beam can be increased.

[Brief description of the drawings]

FIG. 1 is a sectional view of a deflection electrode according to a first embodiment of the present invention, FIG. 2 is a sectional view of a deflection electrode according to a second embodiment of the present invention, and FIG. 3 is a third embodiment of the present invention. It is sectional drawing of the example deflector. [Explanation of Signs of Main Parts] 1a to 1d: deflecting electrode, 2: ceramic cylinder, 3: concave groove, 5, 5a to 5d: metal film, 7a to 7d: space between electrodes, 8a to 8d …… Assembly jig.

Continuation of the front page (72) Inventor Kenji Morita 1-6-3 Nishioi, Shinagawa-ku, Tokyo Nikon Oi Works Co., Ltd. (56) References JP-A-2-247966 (JP, A) JP-A-59- 46744 (JP, A) JP-A-63-110542 (JP, A) JP-A-64-89135 (JP, A)

Claims (3)

(57) [Claims] 1. An electrostatic deflecting device having a multi-pole deflecting electrode inside one concentric cylindrical insulating material, wherein the inner peripheral surface of the cylinder has a width between the deflecting electrodes at a position of a space between the deflecting electrodes. Wide, the cross section is provided with a concave part of a part of a circle, a conductive film having a width wider than the inter-electrode space is provided at the center of the concave part,
An electrostatic deflecting device characterized in that the conductor film is grounded. 2. A method of manufacturing an electrostatic deflection device having a multipolar deflection electrode inside one concentric cylindrical insulating material,
After assembling by fitting a jig into the positioning space formed between the electrodes, the jig is dissolved with a chemical or the like, dissolved by overheating, or removed by utilizing the difference in carbonization or thermal expansion by combustion. A method of manufacturing an electrostatic deflection device. 3. An electrostatic deflecting device having a multi-pole deflecting electrode inside one concentric cylindrical insulating material, wherein the inner peripheral surface of the cylinder is located at the center of the space between the deflecting electrodes. A method for manufacturing an electrostatic deflecting device, comprising: providing a wide grounded conductor film; and providing a relief to the deflection electrode so as not to contact the conductor film.