JP2005203537A - Lightweight high rigid ceramic member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightweight high rigid ceramic member which is suitable for a member moving fast in a semiconductor manufacturing equipment, or the like. <P>SOLUTION: The ceramic member 10 has a honeycomb structure member 13 having a plurality of columnar space 12 partitioned by a bulkhead 11, and a plate member 14. The aperture of the honeycomb structure member 13 is set to 3 mm to 20 mm, a Young's modulus of the bulkhead 11 is set to 200 GPa or more, and the thickness of the bulkhead 11 is set to 0.2 mm to 3 mm. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lightweight high-rigidity ceramic member suitably used for, for example, a movable stage equipped in a semiconductor manufacturing apparatus.

  For example, in the manufacturing process of a semiconductor device, a predetermined pattern is formed on a semiconductor wafer by photolithography, and a stage for holding and moving the semiconductor wafer in an exposure apparatus used in this photolithography process There is a need for a high-precision positioning function that can cope with miniaturization and high integration of circuit patterns of semiconductor devices and a high-speed movement function for performing exposure processing economically.

  However, if the stage is moved at a high speed, vibrations are inevitably generated and the positioning accuracy is lowered. In particular, the movable part of the exposure apparatus repeats moving and stationary, and vibration due to inertial force occurs when stationary. Since such vibration affects exposure accuracy, it is necessary to wait until the magnitude is attenuated to an allowable level or less, which becomes an obstacle to improving the throughput.

  In order to move the stage at a high speed under a constant driving force, it is necessary to reduce the weight of the entire movable part, and to prevent a decrease in accuracy due to vibration during movement and stop, the load deformation must be small. Is preferred. Therefore, in order to achieve both high speed and high positioning accuracy in this way, a structure and material that is lightweight and has little load deformation are required. Here, the magnitude of vibration due to inertial force has a correlation with the specific rigidity of the member, and the greater the member specific rigidity, the smaller the magnitude of vibration. Therefore, reducing the load deformation increases the specific rigidity. Is equivalent to

Under such circumstances, Patent Document 1 proposes a member for an exposure apparatus in which the internal structure of the rib structure portion of the member having the rib structure is a rib structure. With this technique, the exposure apparatus member such as a stage can be made lighter than in the case of a normal rib structure. However, the specific rigidity is lowered due to the high porosity of the rib part, and the arrangement of the ribs must be designed in consideration of the local load deformation due to the structure, and the load deformation of the normal rib structure It is difficult to make the deformation amount less than the amount.
JP 2003-109982 A

  This invention is made | formed in view of such a situation, and it aims at providing the lightweight high-rigidity ceramic member suitable for the member moved at high speed in a semiconductor manufacturing apparatus etc.

That is, according to the present invention, a honeycomb structural member made of a predetermined ceramic material and having a number of columnar voids partitioned by partition walls;
A plate member that is made of a predetermined ceramic material and is attached to a surface of at least one of the honeycomb structure members that is perpendicular to the longitudinal direction of the columnar voids,
The honeycomb structure member has a mesh opening of 3 mm to 20 mm, a Young's modulus of the partition wall of 200 GPa or more, and a thickness of the partition wall of 0.2 mm to 3 mm. Provided.
In this lightweight and highly rigid ceramic member, the specific gravity of the partition walls is preferably less than 4.5.

  According to the present invention, a ceramic member that is lightweight and has high rigidity can be obtained. Therefore, when the lightweight high-rigidity ceramic member of the present invention is used as, for example, a movable stage of an exposure apparatus or an inspection apparatus used for manufacturing a semiconductor device, high throughput and high positioning accuracy can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a schematic structure of a lightweight high-rigidity ceramic member (hereinafter simply referred to as “ceramic member”) 10 according to the present invention, FIG. 2 is a cross-sectional view taken along line AA shown in FIG. FIG.
The ceramic member 10 includes a honeycomb structural member 13 having a large number of columnar voids 12 partitioned by partition walls 11 and a surface perpendicular to the longitudinal direction of the columnar voids 12 (hereinafter referred to as “opening surface”). The honeycomb structure member 13 and the plate member 14 are bonded by a predetermined bonding agent (not shown in FIG. 1), as will be described later.

  The opening L of the honeycomb structure member 13 is 3 mm to 20 mm. Here, “aperture” refers to the length of one side when the shape in the cross section perpendicular to the longitudinal direction of the columnar gap 12 (hereinafter referred to as “opening shape”) is a regular polygon. To do. If the mesh opening L is less than 3 mm, the effect of reducing the weight is difficult to obtain. On the other hand, if the mesh opening L exceeds 20 mm, the plate member 14 is greatly bent, which is not preferable. The aperture L of the honeycomb structure member 13 is more preferably 5 mm to 18 mm.

  Note that the opening shape of the columnar void portion of the honeycomb structure member is not limited to a regular polygon. For example, when the opening shape of the columnar void portion is rectangular, the length of both the short side and the long side is When the opening shape of the columnar gap is circular, the diameter needs to be within the range.

  The Young's modulus of the partition walls 11 of the honeycomb structure member 13 is set to 200 GPa or more. When the Young's modulus of the partition wall 11 is less than 200 GPa, the plate member 14 is largely bent, which is not preferable. Further, the thickness t of the partition wall 11 is set to 0.2 mm to 3 mm. When the thickness t of the partition walls 11 is less than 0.2 mm, the honeycomb structure member 13 is likely to be damaged. On the other hand, when the thickness t of the partition walls 11 exceeds 3 mm, it is difficult to obtain a light weight effect.

The specific gravity of the partition wall 11 is preferably less than 4.5. When the specific gravity of the partition wall 11 is 4.5 or more, it is difficult to obtain an effect of weight reduction. The specific gravity of the partition walls 11 depends on the ceramic material constituting the honeycomb structure member 13 and the structure thereof. Examples of the ceramic material applied to the honeycomb structure member 13 include Al ₂ O ₃ , Si ₃ N ₄ , SiC, sialon, SiC / Al composite material, SiC / Si composite material, and the like. However, the ceramic material is not limited to these as long as the Young's modulus is 200 GPa or more and preferably the specific gravity is less than 4.5. For the plate member 14, the same ceramic material as that of the honeycomb structure member 13 is preferably used.

  The member specific gravity of the ceramic member 10, that is, the weight per unit volume of the ceramic member 10, is preferably 1.6 or less from the viewpoint of reducing the weight of the entire ceramic member 10.

  As a manufacturing method of the plate member 14, a forming aid such as a binder is added to the ceramic raw material powder and granulated, which is formed into a plate shape by a press forming method or the like, and then degreased and fired to obtain a plate-like baking. Examples of the method include obtaining a bonded body, and cutting, grinding, and polishing this. In the case of a SiC / Si composite material, first, a SiC powder and a carbon powder are mixed and molded by a press molding method or the like to prepare a preform, and the preform and metal Si are heated at 1600 ° C. in an inert atmosphere. A SiC-Si composite material can be obtained by heating to a certain extent to melt metal Si and impregnating the preform with molten Si.

  As a method for manufacturing the honeycomb structure member 13, a known extrusion method is preferably used. That is, a method in which a forming aid such as a binder is added to the ceramic raw material powder and kneaded, and the obtained kneaded soil is formed into a honeycomb shape by an extrusion molding method, degreased and fired is preferably used. Also, for example, in the case of SiC / Si composite material, there is a method of extruding a kneaded soil of SiC powder and carbon powder to form a honeycomb-shaped preform and obtaining the SiC / Si composite material by the impregnation method. Can be adopted.

  As a method of joining the honeycomb structure member 13 and the plate member 14, a conventional method, for example, brazing with a metal brazing material (Au brazing, Ag brazing, Al alloy brazing, Si alloy brazing, etc.), glass paste or ceramic paste is used. A joining method by melting is used.

  The ceramic member of the present invention is not limited to the configuration in which the plate member 14 is provided on one opening surface of the honeycomb structure member 13 as in the ceramic member 10, but the ceramic member shown in the perspective view of FIG. 20, a sandwich panel structure in which plate members 14 and 15 are provided on both opening surfaces of the honeycomb structure member 13 may be used. In the ceramic members 10 and 20, holes or threaded grooves are formed in the plate member 14 (or 15) as necessary, and a stage or the like can be manufactured using such holes.

  In the ceramic member 10, one plate member 14 and one honeycomb structure member 13 are joined. However, the present invention is not limited to this, and a plurality of honeycomb structure members are attached to one plate member 14. It is good also as a structure. Further, the outer diameter of the ceramic member 10 is not limited to a rectangular parallelepiped as shown in FIG.

  In the sandwich panel structure shown in FIG. 4, a model of a ceramic member in which the dimensions of each part were set to the values shown in Table 1 was produced by CAD, and the member specific gravity and deflection of each model were obtained by a finite element method. Here, the opening shape of the columnar voids of the honeycomb structure member is a square, and the value of the opening L in Table 1 is the length of one side of the square. Further, the outer dimensions of the honeycomb structure member were 100 mm long × 100 mm wide × 30 mm high (thickness), and the shape of the plate member was 100 mm long × 100 mm wide × 5 mm thick. The specific gravity (= 2.7) of the partition walls of models 1 to 7 is a general specific gravity of SiC / Si.

  In the analysis of the model, the lower four corners of the ceramic member (that is, the corner of one plate member) are constrained, and a load of 5 kg is applied to the upper surface center (that is, the center portion of the other plate member) 20 mm × 20 mm It was. In the analysis result, the case where the specific gravity of the member is 1.6 or less and the deflection is 200 nm or less is set as an acceptance criterion in consideration of actual use.

  The results are also shown in Table 1. As in models 1 to 4, when the mesh opening was in the range of 3 to 20 mm, the specific gravity of each member was as light as 1.6 or less, and the deflection was as small as 200 nm or less. On the other hand, when the aperture is as small as 2 mm as in the model 5, or when the partition wall thickness is as thick as 4 mm as in the model 6, or when the specific gravity of the partition wall is as large as 4.5 as in the model 9, In either case, the member specific gravity was larger than 1.6. The bending analysis is not performed for the model whose member specific gravity is larger than 1.6. Further, when the mesh opening was as large as 24 mm as in the model 7 and when the Young's modulus was small as in the model 8, the deflections were 225 nm and 484 nm, respectively, which were larger than 200 nm determined as the acceptance criteria.

  To 100 parts by mass of Si powder, 40 parts by mass of C (carbon) powder, 15 parts by mass of methylcellulose, and 25 parts by mass of pure water were added and kneaded. Molded into shape. The formed body was fired at 2000 ° C. in an argon gas atmosphere to obtain a SiC honeycomb structure member. The honeycomb structure member has an opening of 10 mm, a partition wall thickness of 1 mm, and an outer dimension of 100 mm × 100 mm × 30 mm. In addition, Si powder and C powder are blended in the above ratio, a predetermined amount of binder is added to this, granulated, and the resulting granulated powder is press-molded and fired under the same conditions as the honeycomb structure member. A member was obtained. The outer dimension of this plate member is 100 mm × 100 mm × 5 mm. The honeycomb structure member thus produced and the plate member were joined using Au brazing to produce a ceramic member having the same configuration as Model 1 shown in Table 1 above.

  A load of 5 kg was applied to the center portion of this ceramic member 20 mm × 20 mm, and the amount of deflection of the loaded surface was measured with an electric micro (Mitutoyo, model number MLH-322), resulting in about 100 nm, and the previous model analysis It was in good agreement with the results. From this, by setting the structural parameters shown in Table 1 and performing the finite element method analysis, the structural parameters of the lightweight and highly rigid ceramic member according to the present invention can be determined substantially.

  The lightweight high-rigidity ceramic member of the present invention is suitable for, for example, an exposure apparatus stage and an inspection apparatus stage.

The perspective view which shows one Embodiment of the lightweight highly rigid ceramic member which concerns on this invention. 1. AA sectional view of FIG. The elements on larger scale of FIG. The perspective view which shows another embodiment of the lightweight high-rigidity ceramic member which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10; Ceramic member 11; Partition 12; Columnar space 13; Honeycomb structure member 14; Plate member 15; Plate member 20;

Claims (2)

A honeycomb structure member made of a predetermined ceramic material and having a number of columnar voids partitioned by partition walls;
A plate member made of a predetermined ceramic material and attached to a surface perpendicular to the longitudinal direction of the columnar voids of at least one of the honeycomb structure members;
A lightweight high-rigidity ceramic member having
The honeycomb structure member has a mesh opening of 3 mm to 20 mm, a Young's modulus of the partition wall of 200 GPa or more, and a thickness of the partition wall of 0.2 mm to 3 mm.   The lightweight high-rigidity ceramic member according to claim 1, wherein the specific gravity of the partition wall is less than 4.5.

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