JPS63110542A - Charged beam irradiating device - Google Patents

Abstract

PURPOSE:To easily obtain high precision with simple structure by composing this device of the following units: a wall surface with specific surface resistivity against a channel of charged beams, an earth part where the wall surface is partially earthed, a conductor electrode film formed on the wall surface, and a voltage introduction part where a voltage is applied to the electrode film. CONSTITUTION:A film 24 with surface resistivity of 10<4>OMEGA to 10<10>OMEGA can be formed for example by performing vacuum evaporation of metal on an inner surface of a container 21. This surface resistivity can be obtained by controlling film thickness while considering a volume intrinsic resistance value of the metal at the time of this evaporation. When the metal with a larger volume intrinsic resistance value is rather selected, the film thickness becomes larger, more controllable, and more stable. An end of the film 24 is earthed with a conductor vacuum container 2 at an earthing part 26, and a conductor electrode film 25 is connected with a voltage introduction terminal 22. Even if scattered electrons generated due to running charged beams are made incident to the film 24, they flow to the earth via the earthing part 26. Therefore, a rise in a potential of the film 24 is very small and so a phenomenon of so-called charge up does not occur.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a charged beam irradiation device for focusing or deflecting a charged beam in a scanning electron microscope, an electron lithography device, an ion microprobe device, or the like.

In conventional scanning electron microscopes, electron lithography systems, ion microprobe systems, and the like, a charged beam is narrowly focused, irradiated onto a target, and deflected. As part of this means, there are an astigmatism correction device and a deflection g1 position, and in these devices, an electrostatic method is sometimes adopted in order to speed up the response speed. FIG. 1 is a sectional view of the electrostatic type deflection V2 position. 1
and 2 are vacuum containers, which are vacuum-sealed by an O-ring 13. Reference numeral 15 denotes a charged beam such as an electron beam emitted from a gun (not shown), and a parallel plate type deflection electrode 3 is arranged across the charged beam. 4 is a support rod that supports the electrode 3, and a lead wire 6 is connected thereto. 10 is an insulating plate for electrically insulating the support rod 4 from the container 1, and 11.12 is an O-ring. Reference numeral 5 denotes an insulating holding plate, which is fixed to the container 1 with screws 7. When a voltage is applied between the two electrodes 3 via the lead wire 6, the charged beam 15 is deflected. As the R7y1 beam 15 travels, scattered electrons are generated in the layers, so in order to avoid charge-up due to this, the container 1 needs to be a conductor, and is generally made of a metal material. The above example is a deflection device, but if the GI arrangement for focusing a charged beam in an astigmatism correction device is also of the static type, the structure is the same, although the number of electrodes is different.

In order to apply a voltage to the deflection electrode 3, a conductor container l is used.
It is necessary to insulate the support rod 4 from the air, which results in a complicated structure. Furthermore, since a large number of parts are piled up, the accuracy of the position and parallelism of the two electrodes 3 is insufficient. Further, in the above example, the electrode 3 is a parallel plate, but
In order to obtain better performance, there are cases where it is desired to make the facing surface of the electrode 3 a cylindrical surface, but in this case, the shape becomes more complicated, manufacturing is difficult, and accuracy is difficult to obtain. In the above points, the conventional technology had many difficulties (and had practical problems).

C.1 Purpose of the Invention The present invention aims to eliminate the drawbacks of the prior art as described above, and to provide a charged beam irradiation device that has a simple structure and is easy to obtain accuracy.

20 Configuration of the Invention The present invention is directed to 104 to 10 opposite to the path of the charged beam.
A wall surface having a surface resistivity of 10Ω, a grounding section for grounding a part of the wall surface, a conductive electrode film formed on the wall surface, and a voltage introducing section for applying a voltage to the electrode film. The present invention relates to a charged beam irradiation device characterized by comprising:

E. Embodiment 2 Figures 2(a) and 2(b) are a longitudinal sectional view and a transverse sectional view showing one embodiment of the present invention. 2.6.13.15 are a conductive vacuum container, a lead wire, an O ring, and a charged beam, respectively, as in FIG.

21 is a vacuum container, which is a cylinder made of an insulating material such as plastic or ceramic. Reference numeral 22 denotes a terminal for introducing voltage, which is sealed to the container 21 by a vacuum sealing part 23, and to which the lead wire 6 is connected. 24 is 1
It is a film having a surface resistivity of 0.04 to 10I0Ω, and is obtained, for example, by vacuum-depositing metal on the inner wall of the container 21. The above surface resistivity can be obtained by controlling the film thickness without considering the volume resistivity of the metal during vapor deposition.The film thickness will be thicker if a metal with a larger volume resistivity is selected, and it can be controlled by controlling the film thickness. Easy to use and stable. One end of the membrane 24 is grounded to the conductive vacuum container 2 at a grounding portion 26 . A conductive electrode film 25 is formed on the film 24 and is connected to the voltage introduction terminal 22 . Electrode film 25
may be formed by vacuum evaporation, or by other methods such as plating (the material is preferably a metal with a small volume resistivity such as steel).

In the device configured in this manner, when a voltage is applied to the electrode g25 from a deflection power source (not shown) via the lead wire 6 and the voltage introduction terminal 22, the electrode film 25 acts as a deflection electrode having a cylindrical surface. Deflect the charged beam 15.

Furthermore, since the film 24 has the resistance value as described above,
Even if scattered electrons generated as the charged beam travels enter the membrane 24, they flow to the ground via the grounding part 26, and the membrane 24
The potential increase is slight. For example, the surface resistivity of the round membrane 24 is 1010Ω, the length to the grounding part of the membrane is 2cm, and the width is 2cm.
When the scattered electrons incident for ms are 10-''A, the potential rise is 0.1 .mu., and the so-called charge-up phenomenon does not occur.

Further, the electrode film 25 is grounded through the film 24, but due to the above-mentioned resistance value of the film 24, the electrode film 25
is substantially insulated from ground. For example, the membrane 24
The surface resistivity is 104Ω, and the length to the grounding part of the membrane is 2c.
When the m5 width is 2 cm and the deflection voltage is IOV, the flowing current is 1 mA, which does not substantially affect the deflection power supply or the deflection characteristics.

As described above, the configuration of the present invention is extremely simple, and therefore easy to manufacture, and has high accuracy because there is no error due to stacking of parts. Further, a cylindrical deflection electrode can be easily manufactured, and deflection accuracy can be improved.

FIG. 3 shows another embodiment, where 30 is 104 to 1010.
It is a vacuum container made of a material with a surface resistivity of Ω. Such a material can be obtained, for example, from a conductive plastic made by mixing carbon particles into plastic. Components other than the container 30 are the same as in FIG. 2. In this case, the inner wall of the container 30 has the above-mentioned surface resistivity, and is similar to the film 24 in FIG. 2 to prevent charging from being caused by scattered electrons. Insulated. This embodiment also has a very simple configuration, easy manufacture, and high precision. Further, a cylindrical deflection electrode can be easily manufactured, and deflection accuracy can be improved.

Although the above embodiment shows the case of a cylindrical deflection electrode, if the inner wall of the container 21 or 30 is made into a prismatic shape, the electrode film 25 can also be made into a parallel plate shape. Further, by arranging eight electrode films 25 on the circumference, it is possible to configure a so-called octapole electrostatic astigmatism correction device, and the charged beam can be focused effectively.

Furthermore, in the case of a structure in which all the components shown in FIGS. 2(a), 2(b), and 3 are placed in a vacuum, an O-ring 13 for vacuum sealing, The vacuum sealing part 23 is not necessary.

The charged beam is not limited to the electron beam shown in the embodiment, but may be an ion beam or the like. Further, the film 24 does not have to be formed by vacuum evaporation; for example, the container 21 may be made of ceramic containing metal, and the metal may be deposited on the inner wall surface by heat treatment. It is sufficient if the wall surface facing the beam has the above-mentioned surface resistivity.

As described in detail in Section 9, the present invention provides a wall surface having a surface resistivity of 104 to 10I0Ω, which faces the path of the charged beam;
By including a grounding part for grounding a part of the wall surface, a conductive electrode film formed on the wall surface, and a voltage introduction part for applying a voltage to the electrode film, the structure can be made into a pipe. The present invention provides a charged beam irradiation device that has high accuracy and can easily produce cylindrical electrodes, and is extremely advantageous in industry.

[Brief explanation of the drawing]

Figure 1 is a sectional view for explaining the prior art, Figure 2 (a
), 2(b) is a vertical cross-sectional view and a cross-sectional view for explaining one embodiment of the present invention, and FIG. 3 is a vertical cross-sectional view for explaining another embodiment of the present invention. In addition, in the symbols shown in the drawings, 1.2.21.30; vacuum container; 3; deflection electrode; 4; support rod; 5; presser plate; 6: lead wire; 7: screw; 10;
Insulating plate, 11.12.13; O-ring, 15; Charged beam, 22; Voltage introduction terminal, 23; Vacuum sealing part, 24;
Membrane, 25; electrode membrane, 26; grounding part. Figure 1

Claims (1)

[Claims] 10^4 to 10^1^ facing the path of the charged beam
A wall surface having a surface resistivity of 0Ω, a grounding section for grounding a part of the wall surface, a conductive electrode film formed on the wall surface, and a voltage introducing section for applying a voltage to the electrode film. A charged beam irradiation device comprising: