JP2014033033A - Electrode unit for electrostatic lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide, in a charged particle beam exposure device, an electrode unit for an electrostatic lens capable of reducing the impact of electrode deflection while decreasing electric field strength at a cathode triple point.SOLUTION: A first electrode 101 and a second electrode 102 are arranged across a space 103, and a support member 104 made of a dielectric is arranged between the first electrode 101 and the second electrode 102. The support member 104 has a first region 104a and a second region 104b, and includes, within the second region 104b, a low-dielectric constant portion 105 having a relative dielectric constant lower than that of the first region 104a.

Description

  The present invention relates to an electrostatic lens electrode unit constituting an electron optical system used in an exposure apparatus and a charged particle beam exposure apparatus using the same.

  Electron beam exposure technology can expose fine patterns of 0.1 μm or less, and is a promising candidate in photolithography in the production process of semiconductor devices.

  Among the electron beam exposure techniques, various multi-beam exposure apparatuses that draw a pattern by simultaneously irradiating a plurality of electron beams without using a mask have been proposed. The number of beams is determined by the number of arrays of electron lenses arranged inside the multi-beam exposure apparatus, and the number of beams is a major factor in determining the throughput of the exposure apparatus. Therefore, in recent years, higher arrangement density is required for multi-beam exposure apparatuses. The multi-beam exposure apparatus uses an electro-optical element for controlling the optical characteristics of the electron beam.

  In particular, the electron lens is classified into an electromagnetic type and an electrostatic type, and the electrostatic type is easier to configure than the electromagnetic type because there is no need to provide a coil core, which is advantageous for downsizing. In particular, a projection lens portion for forming a final image on a wafer requires a short focal lens of 1 mm or less in order to expose a fine pattern. In the case of an electrostatic lens, an electrode substrate constituting the lens A high electric field needs to be applied between them.

  An electrostatic lens for a charged particle beam (hereinafter simply referred to as an “electrostatic lens”) has a voltage application unit, and insulates between a plurality of electrode substrates having a through-hole through which the charged particle beam passes. And a support member for defining the distance between the electrode substrates. Since it is necessary to apply different voltages between the electrode substrates to generate and maintain an electric field strength of about several tens of thousands V / mm, the support member is required to have insulation (pressure resistance).

  In particular, at the cathode triple point, which is the boundary between the cathode side electrode, the support member, and the vacuum region, the electric field is concentrated and it becomes easy to emit electrons. Therefore, it is necessary to reduce the electric field strength at the cathode triple point to improve the pressure resistance. It becomes.

  As a related technology, for example, a structure in which the support member on the side in contact with the cathode side electrode is overhanged with respect to the support member on the side in contact with the anode side electrode to relax the electric field strength at the cathode triple point is proposed. (See Patent Document 1).

International Publication No. 2010/037832

  By the way, the electrostatic lens has a problem of electrostatic attraction generated between the electrode substrates at the same time as reducing the electric field strength at the cathode triple point. An electric field strength is generated between the electrode substrates to which a potential is applied, and an electrostatic attractive force is generated between the electrode substrates. When the electrostatic attractive force is generated, the electrode substrate portion around the through hole through which the charged particle beam passes is not supported by the support member, so that the electrode substrate portion around the through hole is bent. When the electrode is bent, the electrode interval changes, so that the electro-optical characteristics of the electrostatic lens change.

  In the technique of Patent Document 1, the electric field strength at the cathode triple point is relaxed. However, since the support member in contact with the cathode side electrode has a structure in which the support member in contact with the anode side electrode is drawn outward in the surface direction of the electrode, the deflection of the anode side electrode due to electrostatic attraction is applied to the cathode side electrode. There was a problem of increase in comparison (see FIG. 8).

  In view of the above circumstances, the present invention relaxes the electric field strength at the cathode triple point in the charged particle beam exposure apparatus, reduces the influence of electrode deflection, and improves the pressure resistance performance and reduces changes in the electro-optical characteristics. An object of the present invention is to provide an electrode unit for an electrostatic lens.

In order to achieve the above object, an electrode unit for an electrostatic lens according to the present invention includes a first electrode and a second electrode arranged with a space therebetween,
A support member provided between the first electrode and the second electrode, electrically separating the first electrode and the second electrode, and made of a dielectric;
With
The support member has a first region in contact with the first electrode and a second region in contact with the second electrode, and has a dielectric constant higher than that of the first region in the second region. It includes a low dielectric constant portion having a low rate.

  According to the electrode unit for an electrostatic lens according to the present invention, the support member between the first electrode and the second electrode is in contact with the first region and the second electrode in contact with the first electrode. A low dielectric constant portion having a relative dielectric constant smaller than that of the first region is included inside the second region.

  Therefore, the electric field strength at the cathode triple point can be relaxed by the presence of the low dielectric constant portion in the second region, and the second electrode can be supported by a part of the second region. Thereby, it is possible to reduce the deflection of the electrode, improve the pressure resistance performance, and reduce the change in the electro-optical characteristics.

It is a schematic sectional drawing which shows the electrode unit for electrostatic lenses of 1st Embodiment. In 1st Embodiment, it is explanatory drawing which shows the characteristic of the electric field strength in the cathode triple point, and the deflection amount of an electrode. In 1st Embodiment, it is explanatory drawing which shows the relationship between the electric field strength in a cathode triple point, and the deflection amount of an electrode. It is a top view which shows a supporting member. It is a schematic sectional drawing which shows the electrode unit for electrostatic lenses of 2nd Embodiment. It is a schematic sectional drawing which shows the electrode unit for electrostatic lenses of 3rd Embodiment. It is the schematic which shows the electron beam drawing apparatus in 4th Embodiment. It is a schematic sectional drawing which shows the structure of the electrode unit for electrostatic lenses of a conventional structure.

  Hereinafter, embodiments of an electrode unit for an electrostatic lens according to the present invention will be described with reference to the drawings.

<First Embodiment>
[Configuration of Electrode Unit for Electrostatic Lens]
A first embodiment of an electrode unit for an electrostatic lens according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view illustrating an electrode unit for an electrostatic lens according to a first embodiment. Note that the present invention is not limited to the electrostatic lens electrode unit including two or three electrodes as shown in FIG. 1, but can be applied to an electrode unit including four or more electrodes.

  FIG. 1A shows a configuration of an electrode unit 100 for an electrostatic lens composed of two electrodes. As shown in FIG. 1A, the first electrode 101 and the second electrode 102 are arranged with a space 103 therebetween.

  A support member 104 made of a dielectric material is provided between the first electrode 101 and the second electrode 102 to electrically separate the first electrode 101 and the second electrode 102.

  The support member 104 has a first region 104 a in contact with the first electrode 101 and a second region 104 b in contact with the second electrode 102. The second region 104b of the support member 104 includes a low dielectric constant portion 105 having a relative dielectric constant smaller than that of the first region 104a.

  In FIG. 1B, an electrostatic lens electrode unit 100 including three electrodes is configured as a decelerating Einzel lens.

  As shown in FIG. 1B, in the electrostatic lens electrode unit 100, the first electrode 101 is disposed in the middle part between the two second electrodes 102 via the space 103, respectively. . Between the first electrode 101 and the second electrode 102, the first electrode 101 and the second electrode 102 are electrically separated, and two support members 104 made of a dielectric are provided. .

  The first electrode 101 and the second electrode 102 only have to be regulated to a target potential when a voltage is applied from the voltage application unit 110, respectively.

  The first electrode 101 and the second electrode 102 each have a plurality of through holes 107 through which charged particles pass.

  The first electrode 101 and the second electrode 102 have a disk shape, for example. As the constituent material of the first electrode 101 and the second electrode 102, for example, a semiconductor material such as a silicon wafer, a metal such as molybdenum or titanium, or a conductive film is coated on the surface of the material to ensure conductivity. However, the present invention is not limited to the exemplified materials.

  The thickness of each of the electrodes 101 and 102 may be determined depending on the performance of the electrostatic lens, ease of handling during manufacturing, and the like, and the thickness may be different. The thickness of each electrode 101, 102 of this embodiment is set to, for example, about 50 to 300 μm.

  The support member 104 has a function of defining an interval between the first electrode 101 and the second electrode 102 depending on the thickness of the support member 104. The thickness of the support member 104 may be determined depending on the performance of the electrostatic lens, ease of handling during manufacture, and the like, and the thicknesses may be different from each other. The thickness of the support member 104 of this embodiment is set to about 50-500 micrometers, for example.

  The constituent material of the support member 104 may be a dielectric material having a withstand voltage performance required when a voltage is applied, and examples thereof include glass and ceramics, but are not limited to the exemplified materials.

  The support member 104 includes a first region 104 a in contact with the first electrode 101 and a second region 104 b in contact with the second electrode 102. The second region 104b includes a low dielectric constant portion 105 having a relative dielectric constant smaller than that of the support member 104.

  The support member 104 has a support region 104c facing both the space portion 103 and the low dielectric constant portion 105 in the second region 104b. The relative dielectric constant of the low dielectric constant portion 105 may be smaller than the relative dielectric constant of the material of the support member 104 (excluding the low dielectric constant portion 105).

  The electric field strength at the cathode triple point 106 that is the boundary between the first electrode 101, the support member 104, and the space 103 is the smallest when the low dielectric constant portion 105 has a vacuum hollow structure. The low dielectric constant portion 105 need not be limited to a vacuum hollow structure, and may be formed of, for example, a gas-filled cavity, Low-K material, porous glass, or the like. Each member that defines the hollow structure is precisely positioned and fixed with an adhesive (not shown) or the like.

[Operation of electrode unit for electrostatic lens]
Next, the operation of the electrostatic lens electrode unit 100 according to the present embodiment will be described with reference to FIGS.

  With respect to the electrostatic lens electrode unit 100 configured as described above, the first electrode 101 and the second electrode 102 are set so that the first electrode 101 has a lower potential than the second electrode 102. A voltage is applied from the voltage application unit 110 to the circuit. The electric field strength at the cathode triple point 106 at this time varies depending on the shape and material of the support member 104.

  FIG. 8 is a schematic cross-sectional view showing the configuration of a conventional electrostatic lens electrode unit.

  As shown in FIG. 8, the conventional electrostatic lens electrode unit is composed of three electrodes and is configured as a decelerating Einzel lens.

  When a voltage is applied from the voltage application unit 110 to the first electrode 101 and the second electrode 102 of the conventional electrostatic lens electrode unit, an electrostatic attractive force is generated between the first electrode 101 and the second electrode 102. Works. Therefore, as shown in FIG. 8A, the portion of the electrode that is not supported by the support member 104 is bent.

  In the case of the decelerating Einzel lens configuration as shown in FIGS. 1B and 8B, the second electrode 102 is disposed on both sides of the first electrode 101, so electrostatic attraction cancels out. The influence of the bending of the first electrode 101 is mitigated.

  However, since the second electrode 102 does not have a structure that cancels electrostatic attraction, the second electrode 102 is deflected more than the first electrode 101. The amount of bending of the second electrode 102 mainly varies depending on the shape of the support member 104, the shape of the second electrode 102, and the material.

  In the conventional structure of FIG. 8, the support member 104 arranged between the first electrode 101 and the second electrode 102 has a structure in which the side in contact with the second electrode 102 is drawn outward in the surface direction of the electrode. It has become. Therefore, it is considered that the conventional structure of FIG. 8 has a greater deflection of the second electrode 102 due to electrostatic attraction than the structure that is not retracted, and as a result, the change in the electro-optical characteristics of the electrostatic lens is increased.

  As a measure for solving the problems of the conventional structure, it is conceivable that the side contacting the second electrode 102 of the supporting member 104 is not drawn outward in the surface direction, but the side contacting the first electrode 101 is projected. . However, when the side in contact with the first electrode 101 is projected, the portion of the through hole through which the charged particle beam passes approaches the insulating member. When the through-hole portion approaches the insulating member, if the support member 104 is charged for some reason, there is a possibility that the trajectory of the charged particles may be affected.

  In addition, a measure to make the electrode itself difficult to bend by increasing the thickness of the second electrode 102 can be considered. When the electrode is thickened, the electrostatic lens itself is thickened. However, an electrostatic lens that projects a fine pattern onto a wafer usually has a short focal length of 1 mm or less, so the focal length may not be shortened due to mechanical interference between the electrostatic lens and the wafer. There are limits to this measure.

  Therefore, in the electrostatic lens electrode unit 100 of the present embodiment, the support member 104 has a first region 104a in contact with the first electrode 101 and a second region 104b in contact with the second electrode 102 (see FIG. 1). ). Further, the second region 104b includes a low dielectric constant portion 105 having a relative dielectric constant smaller than that of the first region 104a. That is, in the electrostatic lens electrode unit 100 of the present embodiment, the electric field strength at the cathode triple point 106 is alleviated due to the presence of the low dielectric constant portion 105 in the second region 104b, and in part of the second region 104b. The second electrode 102 is supported by a certain support region 104c.

  Focusing on the shape of the support member 104, the electric field strength at the cathode triple point 106 and the deflection amount of the second electrode 102 depend on the overhang amount L in the conventional structure as shown in FIG. In the present embodiment as in b), it depends on the width d of the support region 104c.

  FIG. 2 is a diagram illustrating changes in the electric field intensity at the cathode triple point 106 and the deflection amount of the second electrode 102 when the overhang amount L of the conventional structure or the width d of the support region 104c in the present embodiment is changed. FIG.

  As shown in FIG. 2, in any structure, when L or d is changed so that the electric field intensity at the cathode triple point 106 is decreased, the amount of deflection of the second electrode 102 is increased.

  Next, with reference to FIG. 3, the relationship between the electric field strength at the cathode triple point and the amount of deflection of the electrode was examined, and the effect of the electrostatic lens electrode unit 100 of the present embodiment was confirmed. FIG. 3 is an explanatory diagram showing the relationship between the electric field strength at the cathode triple point and the amount of deflection of the electrode in this embodiment.

  As shown in FIG. 3, in the structure of the electrostatic lens electrode unit 100 of the present embodiment, when the electric field strength of the cathode triple point 106 is equal to that of the conventional structure, the amount of bending of the second electrode 102 is made smaller. Was found to be possible. Thus, by using the configuration of the electrostatic lens electrode unit 100 of the present embodiment, it is possible to reduce the shape change and suppress the deterioration of the electro-optical characteristics while exhibiting the effect of reducing the electric field strength. confirmed.

  As described above, according to the electrostatic lens electrode unit 100 of the present embodiment, the support member 104 between the first electrode 101 and the second electrode 102 is in contact with the first electrode 101. Region 104 a and the second region 104 b in contact with the second electrode 102. The second region 104b includes a low dielectric constant portion 105 having a relative dielectric constant smaller than that of the first region 104a. Therefore, the electric field strength at the cathode triple point 106 can be relaxed by including the low dielectric constant portion 105 in the second region 104b.

  Further, since the low dielectric constant portion 105 exists in the second region 104b, the second region 104b in contact with the second electrode 102 is different from the first region 104a in contact with the first electrode 101. The structure does not lead to the outside of the electrode surface. That is, according to the electrostatic lens electrode unit 100 of the present embodiment, the support region 104c, which is a part of the second region 104b, supports the second electrode 102 and reduces the bending of the second electrode 102. It is possible to improve the pressure resistance performance and reduce the change in the electro-optical characteristics.

<Second Embodiment>
With reference to FIG. 5, a second embodiment of the electrode unit for electrostatic lens according to the present invention will be described. FIG. 5 is a schematic cross-sectional view showing an electrostatic lens electrode unit according to the second embodiment.

  As shown in FIG. 5, the electrostatic lens electrode unit 200 according to the present embodiment includes three electrodes, and is configured as a decelerating Einzel lens.

  The electrostatic lens electrode unit 200 according to the present embodiment is different from the first embodiment in that the first region 104a and the second region 104b of the support member 104 are made of different materials. Specifically, the relative dielectric constant ε2 of the second region 104b of the support member 104 is smaller than the relative dielectric constant ε1 of the first region 104a and larger than the relative dielectric constant ε3 of the low dielectric constant portion 105. have. The relative dielectric constant ε2 of the second region 104b may have the above relationship at least in the portion of the support region 104c facing both the space 103 and the low dielectric constant 105, and the second region 104b Need not have the above relationship.

  The electrostatic lens electrode unit 200 of the present embodiment has basically the same functions and effects as those of the first embodiment. In particular, in the electrostatic lens electrode unit 200 of the present embodiment, the relative dielectric constant ε2 of the second region 104b is smaller than the relative dielectric constant ε1 of the first region 104a, and the relative dielectric constant of the low dielectric constant portion 105 is. It has a relationship greater than ε3. Therefore, according to the electrostatic lens electrode unit 200 of the present embodiment, the electric field strength at the cathode triple point 106 can be made smaller than that of the first embodiment.

<Third Embodiment>
With reference to FIG. 6, a third embodiment of the electrode unit for electrostatic lenses according to the present invention will be described. FIG. 6 is a schematic cross-sectional view illustrating an electrode unit for an electrostatic lens according to a third embodiment.

  As shown in FIG. 6, the electrostatic lens electrode unit 300 of the present embodiment is composed of three electrodes, and is configured as a decelerating Einzel lens.

  The electrostatic lens electrode unit 300 of the present embodiment is different in that the portion facing the space 103 of the support region 104c has a recess 120 with respect to the portion facing the space 103 of the first region 104a. . The support region 104 c is a region facing both the space portion 103 and the low dielectric constant portion 105.

  The recess 120 formed in the portion of the support region 104c facing the space 103 is recessed outward in the surface direction of the electrode with respect to the portion of the first region 104a facing the space 103. The step amount of the recess 120 corresponds to the overhang amount L. The support region 104c is a part of the second region 104b, and the second region 104b includes a low dielectric constant portion 105 having a relative dielectric constant smaller than that of the first region 104a. Therefore, the overhang amount L in the present embodiment can be realized with a smaller value than the conventional structure of FIG.

  The electrostatic lens electrode unit 300 of the present embodiment has basically the same functions and effects as those of the first embodiment.

  In particular, in the electrostatic lens electrode unit 300 of the present embodiment, the portion of the support region 104c that faces the space 103 has a recess with respect to the portion of the first region 104a that faces the space 103. Therefore, according to the electrostatic lens electrode unit 300 of the present embodiment, when the electric field intensity at the cathode triple point 106 is equivalent to that of the conventional structure, the overhang amount L corresponding to the step amount of the recess 120 is equal to the conventional structure of FIG. It is possible to realize with a smaller value. Therefore, it is possible to reduce the influence of electrode deflection.

<Fourth Embodiment>
With reference to FIG. 7, a fourth embodiment of the electrode unit for electrostatic lens according to the present invention will be described. FIG. 7 is a schematic view showing an electron beam drawing apparatus according to the fourth embodiment.

  Examples of the electron beam drawing apparatus 400 in the present embodiment include a multi-beam exposure apparatus.

  As shown in FIG. 7, the electron beam emitted from the electron source 1 is adjusted to a collimated electron beam 1 a by adjusting the lens power of the electrostatic collimator lens 2 by the lens control circuit 21. This electron beam 1 a irradiates the shielding member 10. The shielding member 10 has a plurality of openings.

  The electron beam 1 b that has passed through the opening of the shielding member 10 is irradiated to the aperture array 11. The opening of the shielding member 10 is installed so as to include the shaping opening of the aperture array 11. Therefore, the shape of the electron beam 1c is controlled by passing through the shaping opening of the aperture array 11 and shaped.

  The plurality of electron beams that have passed through the aperture array 11 are imaged at the arrangement position of the blanker array 4 by adjusting the lens power of the first focusing lens 3 by the lens control circuit 21.

  The blanker array 4 is a device having individual deflection electrodes. The blanker array 4 individually performs beam on / off control based on the blanking signal generated by the blanker array control circuit 22. Where the beam is on, no voltage is applied to the deflection electrode, and the electron beam passes through without being deflected. Where the beam is off, a voltage is applied to the deflection electrode to deflect the electron beam.

  The electron beam 1d deflected by the blanker array 4 is blocked by the stop aperture array 5 in the subsequent stage, and the beam is turned off. The electron beam that has passed through the stop aperture array 5 is imaged by the second focusing lens array 6, further focused by the third focusing lens 8, and imaged on the wafer 9.

  Scanning of the electron beam on the wafer 9 can be performed by the deflector 7. The deflector 7 is formed by a counter electrode. The deflector 7 is composed of four counter electrodes for performing two-stage deflection in the X and Y directions (in FIG. 7, for convenience of illustration, the four-stage deflector is represented as one unit. ) The deflector 7 is driven in accordance with a signal from the deflector control circuit 23.

  During pattern drawing, the wafer 9 is continuously moved by the stage 12 in the X direction according to the signal of the stage drive control circuit 24, and the electron on the surface of the wafer 9 is based on the measurement result in real time by the laser length measuring machine. The beam is deflected by the deflector 7 in the Y direction. At the same time, the blanker array 4 individually turns the beams on and off according to the drawing pattern. Thereby, a desired pattern can be drawn on the wafer surface at high speed.

  In the charged particle beam exposure apparatus 400 of the present embodiment, as the first focusing lens 3, the second focusing lens array 6, and the third focusing lens 8, the electrostatic lens electrode unit 100 of the first to third embodiments, Apply 200 or 300. By mounting the electrostatic lens electrode unit 100, 200, or 300 of the first to third embodiments, the reliability and performance of the charged particle beam exposure apparatus 400 can be improved.

  The preferred embodiments of the present invention have been described above, but these are examples for explaining the present invention, and the scope of the present invention is not intended to be limited to these embodiments. The present invention can be implemented in various modes different from the above-described embodiments without departing from the gist thereof.

  Hereinafter, the electrode unit for electrostatic lenses according to the present invention will be described in more detail with reference to examples.

<Example 1>
The electrostatic lens electrode unit of Example 1 will be described with reference to FIGS. In the present embodiment, the electrostatic lens electrode unit 100 of FIG. 1B is manufactured.

  As shown in FIG. 1B, each of the first electrode 101 and the second electrode 102 is a double-side polished single crystal disc-shaped silicon wafer having a thickness of 200 μm and a diameter of 100 mm.

  Each electrode 101, 102 has a plurality of through holes 107 through which charged particles pass in a square area with a side of 3 mm at the center. The through holes 107 have a square arrangement with a hole diameter of 30 μm and a pitch of 60 μm, and were formed by photolithography and dry etching.

  The two support members 104 are disk-shaped silicate glass having a thickness of 400 μm and a diameter of 100 mm, and have a through-hole window 201 having a square of 6 mm on one side at the center. An example of a top view of the support member 104 is shown in FIG.

  As shown in FIG. 4, on one side of a disk-shaped silicate glass 200, the periphery of a square part whose one side of the center part is 6.06 mm so that the wall width of the side wall part 202 of the through window 201 is 30 μm. Then, a groove portion 203 having a width of 300 μm and a depth of 200 μm is formed by groove processing. Thereafter, the support member 104 was formed by sandblasting a square through window 201 having a side of 6 mm in the center. The groove 203 becomes the low dielectric constant portion 105 after the electrostatic lens assembly is completed, and the side wall portion 202 of the through window becomes the support region 104c.

  When the electrostatic lens electrode nut is introduced into the vacuum vessel after assembly, the groove 203 is processed to the outermost part of the disk so that the space of the low dielectric constant portion 105 is evacuated, To avoid being isolated.

  The first electrode 101, the second electrode 102, the two support members 104, and the second support member 104, which have been subjected to these processes, 104 and the second electrode 102 were bonded in this order. A heat-resistant silicon-based adhesive was used for bonding. When adhering these members, the discs were bonded so that the central axes of the discs coincided and were parallel. At this time, the support member 104 is disposed so that the surface on which the groove 203 is formed faces the second electrode 102.

  By applying a low voltage (−4 kV) to the first electrode 101 and a reference potential (0 V) to the second electrode 102 by the voltage application unit 110 to the electrostatic lens electrode unit configured in this way, Functions as an electrostatic lens.

  As shown in FIG. 3, when the electric field intensity relaxation at the cathode triple point 106 in the electrostatic lens electrode unit of the present embodiment and the conventional structure is approximately the same, the electrostatic lens electrode unit of the present embodiment It was confirmed that the amount of bending of the second electrode 102 was reduced compared to the conventional structure.

<Example 2>
With reference to FIG. 5, the electrode unit for electrostatic lenses of Example 2 will be described. In this embodiment, the electrostatic lens electrode unit 200 shown in FIG. 5 is produced.

  In this embodiment, the supporting member 104 is bonded to a silicate glass portion having a 220 μm thick silicate glass (relative permittivity of 4.2) and a 180 μm thick silicon nitride (relative permittivity of 7). Example 1 is the same as Example 1 except that a two-layer structure processed in the same manner as in Example 1 is used.

  By the electrostatic lens electrode unit 200 of the present embodiment, the electric field strength of the silicon nitride portion having a large relative dielectric constant is alleviated, and compared with the case where the supporting member 104 is entirely made of silicate glass, the cathode triple point. It was confirmed that the electric field strength at 106 was smaller.

<Example 3>
With reference to FIG. 6, the electrode unit for electrostatic lenses of Example 3 is demonstrated. In the present example, the electrode unit 300 for electrostatic lenses shown in FIG. 6 is produced.

In this example, the support member 104 was the same as Example 1 except that the following two silicate glasses were bonded together and the first silicate glass was processed in the same manner as Example 1. is there. Due to the two-layer structure of silicate glass having different through window sizes, an overhang amount L of 50 μm is generated in the through windows between the silicate glasses.
First silicate glass: silicate glass having a thickness of 220 μm and a square through window having a side of 6.1 mm at the center.
Second silicate glass: a silicate glass having a square through window with a thickness of 180 μm and a side of 6 mm on one side.

  According to the electrostatic lens electrode unit 300 of the present embodiment, the relationship between the relaxation of the electric field intensity at each cathode triple point 106 and the amount of deflection of the second electrode 102 as compared with the conventional structure is also shown in FIG. It was confirmed that the same results as in 3 were obtained.

100: Electrode lens electrode unit, 101: First electrode, 102: Second electrode, 103: Space part, 104: Support member, 104a: First region, 104b: Second region, 104c: Support Region, 105: low dielectric constant part, 106: cathode triple point, 107: through-hole through which charged particles pass, 110: voltage application part

Claims (7)

A first electrode and a second electrode arranged with a space therebetween,
A support member provided between the first electrode and the second electrode, electrically separating the first electrode and the second electrode, and made of a dielectric;
With
The support member has a first region in contact with the first electrode and a second region in contact with the second electrode, and has a dielectric constant higher than that of the first region in the second region. An electrostatic lens electrode unit comprising a low dielectric constant portion having a low rate.   The electrostatic lens electrode unit according to claim 1, wherein the low dielectric constant portion has a hollow structure.   3. The electrostatic lens electrode unit according to claim 1, wherein the potential applied to the first electrode is lower than the potential applied to the second electrode.   The relative permittivity of the support member in the second region is smaller than the relative permittivity of the support member in the first region and larger than the relative permittivity of the low permittivity portion. Item 4. The electrostatic lens electrode unit according to any one of Items 1 to 3.   5. The electrostatic lens electrode unit according to claim 1, further comprising a concave portion on a side of the second region facing the space portion. 6.   6. The electrostatic lens according to claim 1, wherein the first electrode and the second electrode have a plurality of through holes through which charged particles pass through the space portion. 6. Electrode unit.   A charged particle beam exposure apparatus comprising the electrostatic lens electrode unit according to claim 1 mounted as an electrostatic lens.

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