JP2014053408A - Charged particle beam lens and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a charged particle beam lens in which pressure resistance in a peripheral part of the lens is enhanced, and a manufacturing method for manufacturing the charged particle beam lens at low cost.SOLUTION: A charged particle beam lens 1 comprises at least a first electrode 11, a second electrode 12 and an insulator 13 disposed between the first electrode 11 and the second electrode 12. Each of the insulator 13, the first electrode 11 and the second electrode 12 includes at least one beam passing part (21, 22, 23) for passing a charged beam therethrough. An outer edge of the first electrode 11 is disposed inside of an outermost edge of the insulator 13 and an outer edge of the second electrode 12, and a step is provided in a direction where at least a part of a surface of the insulator 13 which is exposed without contacting the first electrode 11 is retracted with respect to a coarse surface 14 or a contact surface between the first electrode 11 and the insulator 13.

Description

  The present invention relates to a charged particle beam lens constituting an electron optical system used in an exposure apparatus and a method for manufacturing the same.

  In producing semiconductor devices, electron beam exposure technology is a promising candidate for next-generation lithography technology that enables the production of fine patterns with a size of 0.1 μm or less. An exposure apparatus used in the electron beam exposure technique includes an electron optical element for controlling the optical characteristics of the electron beam. The exposure apparatus also includes an electron lens for controlling the beam diameter and aberration of each electron beam. Here, there are an electromagnetic type and an electrostatic type as an electron lens mounted on an exposure apparatus using an electron beam. An electrostatic electron lens does not require a coil core or the like as compared with an electromagnetic (magnetic field) electron lens, and thus has a simple configuration and is advantageous for downsizing and high integration of the device. If the electrostatic lens can be miniaturized and highly integrated, the number of electron beams used and the density can be increased, resulting in the required throughput and resolution line width of the exposure apparatus. Leads to higher performance.

  By the way, since an electrostatic electron lens applies a voltage between a pair of electrodes provided on the lens, the member provided between the electrodes is required to have insulation (pressure resistance). Here, as an attempt to improve the pressure resistance of the electron lens, there is a method proposed in Patent Document 1. Specifically, in a substrate having a voltage application part, an insulation part is disposed between a part in contact with the inter-substrate insulator and the voltage application part, and the voltage application part and the insulator are electrically separated (insulated). It is a technique.

JP 2005-57110 A

  Recently, as the exposure apparatus further increases in throughput and exposure pattern further increases in definition, it is required to apply a higher electric field between the electrodes included in the charged particle beam lens. However, when a high electric field is applied between the electrodes in the load current element lens lens having the configuration of Patent Document 1, discharge may occur due to insufficient withstand voltage.

  The mechanism is as follows. An electrostatic charged particle beam lens has a structure in which electrodes are stacked via an insulator, and the boundary between the vacuum region, the insulator, and the electrode is a triple point. When an electric field is applied between the electrodes, electrons are emitted from the triple point on the cathode side due to the electric field concentration effect, or a secondary electron avalanche phenomenon occurs on the insulator surface. It tends to occur.

  Recently, with the miniaturization of charged particle beam lenses, delicate alignment and handling have been required during lens assembly. At this time, if there is a positional deviation, a scratch, a chip, or the like at the time of assembling in the lens peripheral portion, the electric field concentrates on these scratches in terms of shape, which also causes discharge. That is, in the vicinity of the triple point on the cathode side of the lens periphery, further improvement in pressure resistance has been desired.

  The present invention is made to solve the above-described problems, and an object of the present invention is to provide a charged particle beam lens with improved pressure resistance in the lens peripheral portion and a manufacturing method for manufacturing the charged particle beam lens at a low cost. Is to provide.

The first aspect of the charged particle beam lens of the present invention has at least a first electrode and a second electrode, and an insulator disposed between the first electrode and the second electrode,
Each of the insulator, the first electrode, and the second electrode has at least one beam passing portion for allowing a charged beam to pass therethrough;
The outer peripheral edge of the first electrode is a charged particle beam lens arranged on the inner side of the outermost peripheral edge of the insulator and the outer peripheral edge of the second electrode,
At least a part of the surface of the insulator exposed without contacting the first electrode is a rough surface.

The second aspect of the charged particle beam lens of the present invention has at least a first electrode and a second electrode, and an insulator disposed between the first electrode and the second electrode,
Each of the insulator, the first electrode, and the second electrode has at least one beam passing portion for allowing a charged beam to pass therethrough;
The outer peripheral edge of the first electrode is a charged particle beam lens arranged on the inner side of the outermost peripheral edge of the insulator and the outer peripheral edge of the second electrode,
A step is provided in a direction in which at least a part of the surface of the insulator exposed without contacting the first electrode recedes from the contact surface between the first electrode and the insulator. It is characterized by.

  It is possible to provide a charged particle beam lens with improved pressure resistance in the lens periphery and a manufacturing method for manufacturing the charged particle beam lens at low cost.

It is a schematic diagram which shows 1st embodiment in the charged particle beam lens of this invention, (a) is a top view, (b) is sectional drawing. It is a cross-sectional schematic diagram which shows the specific example of the manufacturing process of the charged particle beam lens of FIG. It is a plane schematic diagram which shows the example of the electrode produced in 1st embodiment. It is a plane schematic diagram which shows the example of the insulator produced in 1st embodiment. It is a cross-sectional schematic diagram which shows the specific example of the manufacturing process of the charged particle beam lens of FIG. It is a cross-sectional schematic diagram which shows the specific example of the manufacturing process of the charged particle beam lens of FIG. It is a figure explaining the pressure | voltage resistant improvement effect which the charged particle beam lens of this invention and the charged particle beam lens of this invention bring about. It is a schematic diagram which shows 2nd embodiment in the charged particle beam lens of this invention. It is a schematic diagram which shows 3rd embodiment in the charged particle beam lens of this invention. 6 is a schematic view showing an electrode produced in Example 3. FIG. 6 is a schematic diagram showing an insulator produced in Example 3. FIG. 10 is a schematic cross-sectional view illustrating a joining process performed in Example 3. FIG. 6 is a schematic diagram for explaining a chamfering process performed in Example 3. FIG.

  The charged particle beam lens of the present invention includes at least a first electrode and a second electrode, and an insulator disposed between the first electrode and the second electrode.

  In the present invention, each of the insulator, the first electrode, and the second electrode has at least one beam passing portion for allowing the charged beam to pass therethrough. In the present invention, the outer peripheral edge of the first electrode is disposed on the inner side of the outermost peripheral edge of the insulator and the outer peripheral edge of the second electrode.

  Furthermore, in the present invention, at least a part of the surface of the insulator that is exposed without contacting the first electrode is a rough surface, or recedes with respect to the contact surface between the first electrode and the insulator. A step is provided in the direction of the movement. In addition, the direction retreating with respect to the contact surface between the first electrode and the insulator has substantially the same meaning as the direction moving away from the contact surface between the first electrode and the insulator.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[First embodiment]
<Charged particle beam lens>
FIG. 1 is a schematic view showing a first embodiment of the charged particle beam lens of the present invention, wherein (a) is a plan view and (b) is a cross-sectional view.

  The charged particle beam lens 1 in FIG. 1 includes a first electrode 11 and a second electrode 12 and an insulator 13 disposed between the first electrode 11 and the second electrode 12. In the charged particle beam lens 1 of FIG. 1, each of the first electrode 11, the second electrode 12, and the insulator 13 has one beam passing portion (21, 22, 23) for passing a charged beam (electron beam). Have more. Further, the charged particle beam lens 1 of FIG. 1 has at least one communication hole 20 by communicating each beam passage portion (21, 22, 23). In the charged particle beam lens 1 of FIG. 1, the outer peripheral edge portion of the first electrode 11 is disposed inside the outer peripheral edge portion of the second electrode 12 and the outermost edge portion of the insulator 13. For this reason, the insulator 13 is partially exposed on the surface in contact with the first electrode 11. In the present invention, the exposed portion of the insulator 13 is a rough surface 14. However, the present invention is not limited to this, and a step provided in a direction retreating with respect to a contact surface between the first electrode 11 and the insulator 13 described later may be used instead of the rough surface 14.

  In the present invention, at least the outer peripheral edge portion of the first electrode is disposed inside the outermost peripheral edge portion of the insulator and the outer peripheral edge portion of the second electrode. Therefore, in the present invention, the relative positional relationship between the outermost edge portion of the insulator and the outer peripheral edge portion of the second electrode is not particularly limited. For example, as shown in FIG. 1B, the insulator 13 and the second electrode 12 may be arranged so that the outermost edge portion of the insulator and the outer peripheral edge portion of the second electrode coincide with each other. Further, the outer peripheral edge portion of the second electrode 12 may be disposed inside the outermost edge portion of the insulator 13.

<Method for producing charged particle beam lens>
Next, a manufacturing process of the charged particle beam lens 1 of FIG. 1 will be described. FIG. 2 is a schematic cross-sectional view showing a specific example of the manufacturing process of the charged particle beam lens of FIG.

(First electrode, second electrode, insulator)
First, the first electrode 11 having an opening to be the beam passage portion 21, the second electrode 12 having an opening to be the beam passage portion 22, and the insulator 13 having an opening to be the beam passage portion 23 are respectively produced.

  FIG. 3 is a schematic plan view showing an example of electrodes produced in the present embodiment (first embodiment). The electrode material used when producing the 1st electrode 11 and the 2nd electrode 12 which comprise the charged particle beam lens of this invention will not be specifically limited if it is a conductor. In particular, in order to produce a high-performance electrostatic lens, it is preferable to use a substrate having Si from the viewpoint of processing accuracy. Examples of the substrate having Si include a Si substrate and an SOI substrate. Further, the beam passing portions (21, 22) of the respective electrodes (11, 12) are provided by forming through holes in the respective electrodes. When forming a through-hole in an electrode, it is necessary to use a method capable of performing fine shape processing with high accuracy. For example, a process combining lithography and deep dry etching is used. The positions of the through holes (beam passing portions (21, 22)) provided in the respective electrodes (11, 12) are preferably matched between the first electrode 11 and the second electrode 12.

  FIG. 4 is a schematic plan view showing an example of an insulator manufactured in the present embodiment (first embodiment). The insulator 13 constituting the charged particle beam lens of the present invention is provided in order to maintain the distance between the first electrode 11 and the second electrode 12 at a desired distance. The insulating layer 13 is fixed so as to be sandwiched between the first electrode 11 and the second electrode 12 as will be described later. For this reason, the state positioned so that the through-hole (beam passage part (21, 22)) which each of the 1st electrode 11 and the 2nd electrode 12 has may correspond can be maintained.

  The constituent material of the insulator 13 is not particularly limited as long as it is an insulator that does not conduct electricity. For example, borosilicate glass or alkali-free glass can be used. The beam passing portion 23 of the insulator 13 is formed by removing the central portion of the insulator 13 and making the insulating layer 13 itself a donut-shaped member. Examples of a method for forming the beam passage portion 23 included in the insulator include etching and blasting.

  In the present invention, at least the surface of the insulating layer 13 in contact with the first electrode 11 is exposed without being covered with the first electrode 11 and the first region covered with the first electrode 11 (region A in FIG. 4). It is divided into a second area (B area in FIG. 4). Here, in the present invention, the second region is a rough surface 14, or a step is provided in a direction retreating with respect to the contact surface between the first electrode 11 and the insulator 13. A specific method for providing the rough surface 14 and the step will be described later.

(Joint process (FIGS. 2A to 2B))
Next, each member is joined in a state where the insulator 13 is sandwiched between the first electrode 11 and the second electrode 2. First, as shown in FIG. 2A, the first electrode 11 (before processing), the second electrode 12, and the insulator 13 are aligned. In addition, when performing alignment, the distance between each member is not specifically limited. Next, the distance between each member is shortened, and each member is joined as shown in FIG.

  Specific bonding techniques between the electrodes (11, 12) and the insulator 13 include anodic bonding, bonding by fusion bonding, and the like. Also, gold-gold bonding in which a gold thin film is provided at the bonding portion, or bonding using an adhesive that is a simpler method can be employed. However, in order to achieve higher performance as a charged particle beam lens, it is important to realize and maintain a highly accurate positioning state of components, so that the insulator surface and the electrode surface are directly chemically bonded. It is preferable to make it. For this reason, as a joining method of the electrodes (11, 12) and the insulator 13, anodic bonding or fusion bonding is preferable.

  As the bonding between the electrodes (11, 12) and the insulator 13 using anodic bonding, specifically, there is bonding between a silicon electrode and a borosilicate glass insulating spacer. Further, as the bonding between the electrodes (11, 12) and the insulator 13 using fusion bonding, specifically, there is a bonding between a silicon electrode and a borosilicate glass or non-alkali glass insulating spacer. In particular, the bonding of silicon electrodes and borosilicate glass or non-alkali glass insulating spacers using fusion bonding allows the temporary bonding process after alignment to be performed at a low temperature of about room temperature and is not easily affected by expansion and contraction of members. In particular, it is preferable.

  Note that the timing for joining the second electrode 12 and the insulator 13 may be the same as that for joining the first electrode 11 and the insulator 13 as shown in FIGS. Although it is good, it is not limited to this. That is, the second electrode 12 and the insulator 13 may be joined before the first electrode 11 and the insulator 13 are joined, or after the first electrode 11 and the insulator 13 are joined, You may perform after finishing the process of the 1st electrode 11 mentioned later.

(Processing of the first electrode (FIGS. 2B to 2C))
Next, with respect to the member in which the electrode and the insulator are integrated as shown in FIG. 2B, a part of the first electrode 11 is removed and the surface of the insulator 13 on the side in contact with the first electrode 11 is removed. Part is exposed (FIGS. 2B to 2C).

  As a method of processing (cutting / removing) the first electrode 11 after the joining step, for example, a combination of means such as dicing to the first electrode 11, patterning and etching can be mentioned. Here, when dicing to the first electrode 11, for example, as shown in FIG. 2B and FIG. 3, a scribe line 11 a is provided at an arbitrary position of the first electrode 11. 2B shows a region where the rough surface 14 is provided (region B in FIG. 2B) and a region where the rough surface 14 is not provided (of A in FIG. 2B). In this example, the scribe line 11a is provided on the boundary line with the region. The first electrode 11 is diced along the scribe line 11a to partially remove the first electrode 11 in the region where the rough surface 14 is provided. However, the position where the scribe line 11a is provided is not limited to the boundary line between the region B in FIG. 2B and the region A in FIG. 2B, and the rough surface 14 is provided. It may be within the area (area B in FIG. 2B).

  In general, it is preferable that the electrode and the insulator are firmly and strongly bonded. That is, it is generally preferable that the bonding force between the electrode and the insulator is strong. On the other hand, in the first electrode 11, it is necessary to remove unnecessary portions after joining with the insulator 13. In order to perform partial removal of the first electrode 11 reliably and simply, even if the portion of the first electrode 11 to be removed is not joined to the insulator 13 or is joined to the insulator 13. It is desirable that the joining force is small. This is because when the first electrode 11 is diced, the electrode can be easily removed by a mechanical method when the first electrode 11 is not diced or when the bonding strength with the insulator 13 is small. Therefore, in the present invention, for example, the surface of the insulator 13 to be bonded to the first electrode 11 (bonding surface with the first electrode 11) is divided into two regions, that is, the first region and the second region, The joining force with the first electrode 11 in the second region is made smaller than that in the first region. In addition, the 2nd area | region here is the area | region B located in the outer periphery of the 1st area | region A specifically, shown in FIG.2 (b) or FIG.

  However, in the present invention, instead of dividing the insulator 13 (the surface bonded to the first electrode 11) into two regions, the first electrode 11 is divided into two regions (first region and second region). You may divide into.

  Here, in the two regions (first region A and second region B) included in the insulator 13 shown in FIG. 2B and FIG. 4, the bonding with the first electrode 11 in the second region B is performed. A specific method for making the force smaller than that in the first region A will be described.

  In the first method, the first region A is a smooth surface suitable for joining with the first electrode 11, while the second region B is a rough surface 14 with the first electrode 11. A method for reducing the bonding force is mentioned. In bonding methods such as anodic bonding and fusion bonding, it is important that the bonding surface is smooth in order to ensure bonding strength. In other words, it means that it is possible to reduce the bonding force with the first electrode 11 or to prevent the bonding with the first electrode 11 by making the bonding surface rough. In the case of fusion bonding, the insulator 13 cannot be bonded to the first electrode 11 by setting the surface roughness Ra of the bonding surface of the insulator 13 to the first electrode 11 to exceed 2 nm. As described above, in the second region B, by setting the surface roughness of the bonding surface of the insulator 13 to the first electrode 11, the bonding surface even after the insulator 13 is bonded to the first electrode 11. The first electrode 11 can be easily peeled off.

  Here, specific methods of partially roughening the bonding surface of the insulator 13 with the first electrode 11 to make the rough surface 14 include a wet method using BHF, KOH, or the like, a sputtering method, a dry etching method, a blasting method. Law.

  The second method is a method of processing the second region B of the insulator 13 to form a step in a direction retreating with respect to the surface where the first electrode 11 and the insulator 13 are joined. FIG. 5 is a schematic cross-sectional view showing a specific example of the manufacturing process of the charged particle beam lens of FIG. FIG. 5 shows a modification of the manufacturing process shown in FIG.

  In the manufacturing process of FIG. 5, instead of providing the rough surface 14 in FIG. 2, the insulator 13 provided in the second region B of the surface of the insulator 13 on the first electrode 11 side shown in FIG. 2 is the same as the process shown in FIG. 2 except that the step 16 is provided by cutting.

  When the process shown in FIG. 5 is used, as shown in FIG. 5B, in the second region B, the first electrode 11 and the insulator 13 are not in contact with each other. The first electrode 11 and the insulator 13 are not joined. For this reason, when the first electrode 11 is diced, the first electrode 11 provided in the second region B is easily peeled off.

  When manufacturing a charged particle beam lens according to the manufacturing process of FIG. 5, it is preferable to provide the region where the step 16 is provided at least around the region where the first electrode remains when the final lens shape is formed. It is more preferable that the step 16 is formed in the entire region where the first electrode 11 is desired to be removed. When the step 16 is formed in the entire region where the first electrode 11 is to be removed, the first electrode 11 is processed after the first electrode 11 and the insulator 13 are joined (partial removal of the first electrode 11). It can be done more easily. When the process shown in FIG. 5 is performed, the depth of the step 16 provided in the insulator 13 (d in FIG. 5A) is the joining method, the area of the step, and the ease of processing. It can set suitably from these. If the first electrode 11 and the insulator 13 are bonded by fusion bonding, the depth of the step 16 is preferably set to 1 μm or more for the purpose of surely depriving the bonding force.

  In the case where the first electrode 11 and the insulator 13 are bonded using an adhesive, a third method described below can be employed. FIG. 6 is a schematic cross-sectional view showing a specific example of the manufacturing process of the charged particle beam lens of FIG. FIG. 6 is a modification of the manufacturing process shown in FIG.

  The manufacturing process of FIG. 6 is common to the process shown in FIG. 2 except that the adhesive 17 is provided on the first electrode 11 and the second electrode 12 instead of providing the rough surface 14 in FIG. ing. However, in the first electrode 11, the adhesive 17 is applied only to the first region A.

  When manufacturing a charged particle beam lens according to the manufacturing process of FIG. 6, the area | region (the 1st area | region A in FIG. 6 (a)) with which the adhesive agent 17 is apply | coated, and the area | region (FIG. 6 (a)) In the second region B), the bonding force between the first electrode 11 and the insulator 13 is different. For this reason, when the first electrode 11 is diced, the first electrode 11 provided in the region where the adhesive 17 is not applied (second region B in FIG. 6A) is easily peeled off. .

  By the way, in the manufacturing process according to the present invention, a product (charged particle beam lens) can be obtained by joining an electrode and an insulator and then removing an unnecessary portion. Therefore, for the purpose of mass production, a set of electrode substrates is used. This is advantageous when multi-chamfering is performed to produce a plurality of charged particle beam lenses. Compared to the case where the electrodes are divided into a desired number and shape before being bonded to the insulator for the purpose of multi-cavity, the substrate can be held and aligned at the time of bonding more easily and reliably. Therefore, the manufacturing process according to the present invention is a manufacturing method suitable for manufacturing the charged particle beam lens at low cost.

<Operation and effect of the present invention>
Next, the action of the charged particle beam lens of the present invention, specifically, the action of improving pressure resistance will be described. FIG. 7 is a diagram for explaining the pressure resistance improving effect brought about by the charged particle beam lens of the present invention and the charged particle beam lens of the present invention.

  Here, FIG. 7A is a diagram showing an example of the charged particle beam lens of the present invention, and the details thereof are the same as those of the charged particle beam lens 1 shown in FIG. FIG.7 (b) is the elements on larger scale of b part of Fig.7 (a). On the other hand, FIG.7 (c) is a figure which shows the example of the charged particle beam lens used as the comparison object of the charged particle beam lens of this invention. In the charged particle beam lens in FIG. 7C, the insulator 13 is bonded to the first electrode 11 on all the surfaces facing the first electrode 11 as compared with the charged particle beam lens in FIG. Is different. FIG.7 (d) is the elements on larger scale of d part of FIG.7 (c).

  The pressure resistance depends on the creeping withstand voltage distance of the insulator 13, but the creeping withstand voltage distance of the insulator 13 is obtained by the width (cross-sectional distance) of the surface of the insulator 13 that is not joined to the electrodes (11, 12). It is done. In the charged particle beam lens of FIG. 7A, the surface of the insulator 13 that is not bonded to the electrodes (11, 12) corresponds to the portion where the rough surface 14 is provided and the side wall of the insulator 13. To do. Here, when the width (cross-sectional distance) of the portion where the rough surface 14 is provided is x, and the thickness of the insulator 13 (cross-sectional distance of the side wall of the insulator 13) is z, the charging shown in FIG. The creeping pressure resistant distance in the particle beam lens is obtained by x + z. On the other hand, the creeping pressure resistant distance in the charged particle beam lens of FIG. 7C is obtained by the thickness of the insulator 13 (cross-sectional distance of the side wall of the insulator 13) z. That is, in the charged particle beam lens of FIG. 7A, the creeping pressure resistance distance is increased by the distance x (the width (cross-sectional distance) of the portion where the rough surface 14 is provided).

  Further, the equipotential lines in the insulating layer 13 in the charged particle beam lenses of FIGS. 7A and 7C are as shown in FIGS. 7B and 7D, respectively. The equipotential lines shown in FIGS. 7B and 7D are equipotential lines when the first electrode 11 is set to the ground potential and a negative voltage is applied to the second electrode 12. Here, it can be seen from FIG. 7B that the electric field applied to the cathode triple point in the periphery of the lens is relaxed in the charged particle beam lens in FIG. As described above, the charged particle beam lens of the present invention can ensure a long creepage withstand voltage distance and can remarkably improve the withstand voltage because the electric field at the cathode triple point is relaxed.

[Second Embodiment]
As described above, in the first embodiment, the charged particle beam lens including the two electrodes (the first electrode 11 and the second electrode 12) and the single insulator 13 provided between the two electrodes has been described. However, in the present invention, the number of electrodes and insulators constituting the charged particle beam lens is not particularly limited. The present invention can theoretically be applied to a charged particle beam lens including n + 1 (n ≦ 1) electrodes and a total of n insulators provided between the electrodes.

  FIG. 8 is a schematic diagram showing a second embodiment of the charged particle beam lens of the present invention. The charged particle beam lens 2 in FIG. 8A includes a first electrode 11, a second electrode 12, a third electrode 15, a first electrode 11 and a third electrode 15, and a third electrode 15 and a second electrode. And insulators 13 respectively disposed between them. In the charged particle beam lens 2 of FIG. 8A, a beam passing portion (21 for passing a charged beam (electron beam) is passed through the first electrode 11, the second electrode 12, the third electrode 15 and the insulator 13, respectively. , 22, 24, 23). In the charged particle beam lens 2 of FIG. 8A, the outer peripheral edge portions of the first electrode 11 and the second electrode 12 are arranged on the inner side of the outermost edge portion of the insulator 13. For this reason, the two insulators 13 included in the charged particle beam lens 2 of FIG. 8A are partially exposed on the surface in contact with the first electrode 11 or the surface in contact with the second electrode 12. In the charged particle beam lens 2 of FIG. 8A, the exposed portion of the insulator 13 is a rough surface 14.

  The charged particle beam lens 2 in FIG. 8A is used as a so-called Einzel-type electrostatic lens when a negative voltage is applied to the third electrode 15 and the first electrode 11 and the second electrode 12 are ground electrodes. be able to.

  Further, the charged particle beam lens 2 of FIG. 8A has a rough surface area larger than that of the charged particle beam lens 1 of FIG. For this reason, the creeping pressure resistant distance of the charged particle beam lens 2 of FIG. 8A is longer than that of the charged particle beam lens 1 of FIG. Therefore, the charged particle beam lens 2 of FIG. 8A can be expected to have a further improvement in pressure resistance. Moreover, the partial surface of the contact surface with the 1st electrode 11 or the 2nd electrode 12 of the insulator 13 is made into the rough surface 14, Therefore By the method demonstrated in 1st embodiment, the 1st electrode 11 and the 2nd electrode 12 processing (partial removal of electrodes by dicing or the like) can be easily performed.

  In addition, when processing the 1st electrode 11 and the 2nd electrode 12 which are included in the manufacturing process of the charged particle beam lens 2 of Fig.8 (a), the scribe line 11a provided in the 1st electrode 11 and the 2nd electrode 12, respectively. The position of is not particularly limited. The boundary line between the region where the rough surface 14 shown in FIG. 8A is provided and the region where the rough surface 14 is not provided, the region in the region where the rough surface 14 shown in FIG. 8B is provided, the roughness shown in FIG. Any of the regions inside the region where the surface 14 is provided may be used.

[Third embodiment]
FIG. 9 is a schematic view showing a second embodiment of the charged particle beam lens of the present invention. In the charged particle beam lens 3 in FIG. 9A, the exposed portion of the insulator 13 is a contact surface between the electrodes (11, 12) and the insulator 13 as compared with the charged particle beam lens 2 in FIG. The difference is that a step 16 is provided in the direction of retreating.

  The charged particle beam lens 3 in FIG. 9A has a creeping withstand pressure distance longer than that of the charged particle beam lens 1 in FIG. 1 in the same manner as the charged particle beam lens 2 in FIG. Therefore, a further improvement in pressure resistance can be expected as in the charged particle beam lens 2 of FIG. Further, by processing the partial region of the contact surface of the insulator 13 with the first electrode 11 or the second electrode 12 to form a step 16, the first electrode 11 and the second electrode can be formed by the method described in the first embodiment. Processing of the two electrodes 12 (partial removal of electrodes by dicing or the like) can be easily performed.

  In addition, when processing the 1st electrode 11 and the 2nd electrode 12 which are included in the manufacturing process of the charged particle beam lens 3 of Fig.9 (a), the scribe line 11a provided in the 1st electrode 11 and the 2nd electrode 12, respectively. The position of is not particularly limited. The boundary line between the region where the step 16 shown in FIG. 9A is provided and the region where the step 16 is not provided, the region in the region relatively recessed by the step 16 shown in FIG. 9B, FIG. 9C Any of the regions inside the region where the step 16 shown is provided may be used.

  Hereinafter, the present invention will be described by way of examples.

  In this example (Example 1), a charged particle beam lens was manufactured based on the manufacturing process shown in FIG.

(1-1) Electrode As the first electrode 11 and the second electrode 12, single crystal silicon having a thickness of 100 μm was used. For each electrode (11, 12), a plurality of circular through-holes (beam passing portions 21, 22) having a diameter of 100 μm were formed by using photolithography and deep dry etching together.

(1-2) Insulator As the insulating spacer (insulator 13), an alkali-free glass having a thickness of 300 µm was used. First, both surfaces of the insulating spacer were polished to a roughness of Ra <1 nm or less so as to have a surface roughness suitable for fusion bonding. Next, a square through-hole (beam passage portion 23) having a side of 8 mm was formed in the central portion of the insulating spacer by blasting. Next, among the two surfaces of the insulating spacer, the first region A and the second region B are set as shown in FIG. About the area | region B, the 2nd area | region B was made into the rough surface 14 by performing blasting. The surface roughness of the rough surface 14 was Ra = 50 nm.

(2) Joining process Next, the electrodes (11, 12) produced in (1-1) and the insulating spacer (insulator 13) produced in (1-2) are insulated by fusion bonding. The spacers were joined so as to be sandwiched between the first electrode 11 and the second electrode 12. A specific method will be described below.

  First, after cleaning the joint surface of the insulating spacer with the first electrode 11, plasma treatment was performed to activate the joint surface. Next, after aligning the insulating spacer and the first electrode 11, the insulating spacer and the first electrode 11 were temporarily joined at room temperature. Next, annealing was performed by heating to 200 ° C., and the insulating spacer and the first electrode 11 were finally joined. Next, after cleaning the bonding surface of the insulating spacer with the second electrode 12, plasma processing was performed to activate the bonding surface. Next, after aligning the insulating spacer and the second electrode 12, the insulating spacer and the second electrode 12 were temporarily joined at room temperature. Next, annealing was performed by heating to 200 ° C., and the insulating spacer and the second electrode 12 were finally joined.

(3) Processing Step of First Electrode Next, the first electrode 11 was provided with a scribe line 11a as shown in FIG. In addition, this scribe line 11a was made into the boundary line of the 1st area | region A and the 2nd area | region B which were set to the joint surface with the 1st electrode 11 of an insulating spacer, as FIG.2 (b) shows. . Next, the first electrode 11 was diced according to the scribe line 11a. Next, the first electrode 11 in contact with the insulating spacer (rough surface 14 thereof) in the second region B was removed. Since the rough surface 14 was provided in the 2nd area | region B at this time, since the 1st electrode 11 was not substantially joined with the insulating spacer in this area | region, it was able to peel easily from the insulating spacer. (FIG. 2 (c)).

  From the above, the charged particle beam lens 1 shown in FIG. 1 was obtained.

  In this example, the charged particle beam lens 2 shown in FIG.

(1-1) Electrode The 1st electrode 11 which used the single crystal silicon used in Example 1, and formed multiple circular through-holes (beam passage parts 21, 22, and 24) by the same method as Example 1. The second electrode 12 and the third electrode 15 were respectively produced.

(1-2) Insulator The non-alkali glass used in Example 1 is used, and through holes (beam passing portions 23) are provided in a predetermined region by the same method as in Example 1, and the bonding surface with the electrodes Two insulating spacers (insulator 13) that have been subjected to a predetermined surface treatment are produced. Note that the two insulating spacers used in this embodiment are the joint surfaces with the first electrode 11 or the second electrode 12, and the rough surface 14 is formed in the second region B shown in FIG. 4. Is provided.

(2) Joining process Next, the insulating spacer and the electrode were sequentially joined in the same manner as in Example 1. In the bonding, the following processes (2-1) to (2-4) are performed, but the order of performing each process is not particularly limited.
(2-1) Joining of the insulating spacer joined to the first electrode 11 and the third electrode 15 (2-2) Joining of the insulating spacer joined to the second electrode 12 and the third electrode 15 (2-3) Joining of one electrode 11 and insulating spacer (2-4) Joining of second electrode 12 and insulating spacer

(3) Processing Step of First Electrode Next, scribe lines 11 a shown in FIG. 3 were provided on the first electrode 11 and the second electrode 12 in the same manner as in Example 1. Next, the first electrode 11 and the second electrode 12 were diced according to the scribe line 11a. Next, the first electrode 11 in contact with the insulating spacer (rough surface 14) was removed by the same method as in Example 1.

  Thus, a so-called Einzel-type charged particle beam lens 2 was obtained.

  A voltage of −3.7 kV is applied to the third electrode 15 constituting the obtained charged particle beam lens 2, and the upper and lower electrodes (11, 12) are grounded electrodes. When an electron beam was passed through the communication hole formed of 22, 23, 24), no discharge was observed. Therefore, it was confirmed that a highly reliable electron lens capable of stably maintaining a desired lens action for a long time was obtained.

  In accordance with the manufacturing process described below, nine charged particle beam lenses were manufactured from one set of electrode substrates by chamfering.

(1-1) Electrode FIG. 10 is a schematic diagram showing an electrode produced in this example (Example 3). In FIG. 10, (a) is a plan view of the electrode used, (b) is a bb ′ cross-sectional view in (a), and (c) is in (a) and (b). It is an enlarged plan view of the area | region X shown, (d) is dd 'sectional drawing in (c).

  The electrodes (11, 12) shown in FIG. 10 use photolithography and deep dry etching together, and each have a through-hole (beam) of 80 μm in the region X shown in FIG. 10A of single-crystal silicon having a thickness of 150 μm. It was produced by forming the passage parts 21 and 22). Specifically, a total of 25 through holes (beam passage portions 21 and 22) (5 in the row direction × 5 in the column direction) were formed as shown in FIG.

(1-2) Insulator FIG. 11 is a schematic diagram showing an insulator manufactured in this example (Example 3). 11A is a plan view of the insulator used, FIG. 11B is a back view of the insulator used, and FIG. 11C is a cross-sectional view taken along line cc ′ in FIG. It is. In addition, the plane of the insulator 13 shown in FIG. 12A is a joint surface that joins the first electrode 11, and the back surface of the insulator 13 shown in FIG. 12B is a joint that joins the second electrode 12. Surface.

  The insulator 13 in FIG. 11 was produced by the method described below. First, the flat surface and the back surface of non-alkali glass having a thickness of 300 μm were polished to ensure high smoothness on both surfaces (plane and back surface). Next, by processing the insulator 13 using wet etching, rectangular (square) penetrations are made at positions corresponding to the nine regions X provided on the electrodes (11, 12) in FIG. A hole (beam passage 23) was formed. Next, by using wet etching, the insulator 13, specifically, the region B in the plane of the insulator 13 shown in FIG. Formed. At this time, the relative step between the region B and the region A (the difference in relative height between the region A and the region B due to the provision of the step 16) was 50 μm.

(2) Joining process (FIG. 12)
Next, after the relative alignment of the first electrode 11, the second electrode 12, and the insulator 13 was performed (FIG. 12 (a)), the first electrode 11, the second electrode 12 and the insulator 13 were joined in the same manner as in Example 1, and FIG. State.

(3) Chamfering process (Fig. 13)
Next, the two electrodes (11, 12) and the insulator 13 are diced together along the scribe line 11b (boundary line between the outer peripheral portion 30 and the step 16) shown in FIGS. 13 (a1) and (a2). By doing so, the outer peripheral part 30 was cut away (FIG. 13 (b1), (b2)).

  Next, after the first electrode 11 is diced along the scribe line 11c shown in FIGS. 13B1 and 13B2 (the boundary line between the region where the step 16 is provided and the region where the step 16 is not provided), the step is The 1st electrode 11 in the area | region which provided 16 was removed (FIG. 13 (c1), (c2)). In this embodiment, since the used insulator 13 has a step 16 having a depth of 50 μm in a predetermined region (region B in FIG. 11A), the first electrode 11 and the insulator in this region are used. 13 was not joined, and the first electrode 11 could be easily removed.

  Finally, two electrodes (11, 12) and insulation along the scribe line 11d (arbitrary scribe line provided in the region where the step 16 is provided) shown in FIGS. 13 (c1) and (c2) The body 13 was diced together. Thus, nine charged particle beam lenses could be obtained (FIG. 13 (d1) and (d2)). In this embodiment, the process of dicing the two electrodes (11, 12) and the insulator 13 all together is performed first, and then shown in FIGS. 13 (b1) and (b2). You may remove the unnecessary part of the 1st electrode 11 which performed the dicing along the scribe line 11c.

  By the way, in order for the obtained lens to be a lens that can control the charged particle beam with high accuracy, the first electrode 11 and the second electrode 12 are aligned with high accuracy in the joining step. It is essential. In the present invention, the through holes (beam passing portions 21 and 22) included in each electrode are formed with high accuracy using photolithography including the positional relationship between the regions X. Therefore, the alignment of the first electrode 11 and the second electrode 12 can be performed together in a highly accurate state by simply aligning alignment marks (not shown) provided on the respective electrodes (11, 12) with high accuracy. Can be realized. Further, a step 16 is formed in a predetermined region of the joint surface of the insulator 13 with the first electrode 11 so that unnecessary portions of the first electrode 11 can be easily removed after the electrodes (11, 12) and the insulator 13 are joined. Is provided. For this reason, a plurality of charged particle beam lenses can be easily manufactured by setting a scribe line and cutting (dicing) a predetermined member along the scribe line.

  1 (2, 3): charged particle beam lens, 11: first electrode, 11a: scribe line, 12: second electrode, 13: insulator, 14: rough surface, 15: third electrode, 16: step, 17 : Adhesive, 20: Communication hole, 21 (22, 23, 24): Beam passage part (through hole)

Claims (6)

Having at least a first electrode and a second electrode, and an insulator disposed between the first electrode and the second electrode;
Each of the insulator, the first electrode, and the second electrode has at least one beam passing portion for allowing a charged beam to pass therethrough;
The outer peripheral edge of the first electrode is a charged particle beam lens arranged on the inner side of the outermost peripheral edge of the insulator and the outer peripheral edge of the second electrode,
The charged particle beam lens, wherein at least a part of the surface of the insulator exposed without contacting the first electrode is a rough surface. Having at least a first electrode and a second electrode, and an insulator disposed between the first electrode and the second electrode;
Each of the insulator, the first electrode, and the second electrode has at least one beam passing portion for allowing a charged beam to pass therethrough;
The outer peripheral edge of the first electrode is a charged particle beam lens arranged on the inner side of the outermost peripheral edge of the insulator and the outer peripheral edge of the second electrode,
A step is provided in a direction in which at least a part of the surface of the insulator exposed without contacting the first electrode recedes from the contact surface between the first electrode and the insulator. A charged particle beam lens. Having at least a first electrode and a second electrode, and an insulator disposed between the first electrode and the second electrode;
Each of the insulator, the first electrode, and the second electrode has at least one beam passing portion for allowing a charged beam to pass therethrough;
The outer peripheral edge portion of the first electrode is a manufacturing method of a charged particle beam lens disposed inside the outermost peripheral edge portion of the insulator and the outer peripheral edge portion of the second electrode,
A bonding step of bonding at least the first electrode and the insulator;
A first electrode processing step of removing a peripheral portion of the first electrode to expose a part of a bonding surface of the insulator with the first electrode, and a charged particle beam lens comprising: Production method The bonding surface of the insulator with the first electrode has a first region and a second region on the outer periphery of the first region,
The bonding force between the insulator and the first electrode in the second region is smaller than the bonding force between the insulator and the first electrode in the first region,
The charged particle beam lens according to claim 3, wherein the processing step of the first electrode is a step of removing the first electrode bonded to the insulator in the second region. Production method.   The charged particle beam lens manufacturing method according to claim 3, wherein the surface of the second region is a rough surface.   The said insulator has a level | step difference in the direction retreated with respect to the contact surface of said 1st electrode and said insulator in said 2nd area | region, The said Claim 3 or 4 characterized by the above-mentioned. Manufacturing method of charged particle beam lens.

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