WO2019155909A1

WO2019155909A1 - Structural body, method for manufacturing structural body, and machining device

Info

Publication number: WO2019155909A1
Application number: PCT/JP2019/002422
Authority: WO
Inventors: 田中　米太
Original assignee: ウシオ電機株式会社
Priority date: 2018-02-07
Filing date: 2019-01-25
Publication date: 2019-08-15
Also published as: JP2019136889A

Abstract

Disclosed are a structural body having better characteristics as a material of a machining device frame or the like, a method for manufacturing the structural body, and a machining device employing the structural body. A structural body (CFRP structural body) (10) has a structure in which a first material having carbon fibers as a main component, and a second material having a main component other than carbon fibers are integrated. The thermal expansion coefficient of the first material and the thermal expansion coefficient of the second material have opposite signs, and the thickness of the second material is less than the thickness of the first material. Such a structural body (10) can be used as a frame for supporting a component member of a machining device.

Description

Structure, structure manufacturing method and processing apparatus

The present invention relates to a structure including carbon fibers, a method for manufacturing the structure, and a processing apparatus using the structure.

Conventionally, in a processing apparatus such as an exposure apparatus or a laser processing apparatus, the frame that supports the constituent members is made of a metal such as iron. In the case of an exposure apparatus, the frame supports components such as a light irradiation unit, a mask stage, a projection lens, and a work (substrate) stage. In the case of a laser processing machine, the frame supports structural members such as a laser device and a work stage.
In such a processing apparatus, when the ambient temperature changes or the apparatus itself generates heat, the metal frame expands and contracts due to thermal expansion. When the frame expands and contracts, the position of the above-described component member supported by the frame may change, and the processing accuracy may be reduced.
Therefore, it is desirable to use a material having a thermal expansion coefficient as low as possible as the material of the frame of the processing apparatus.

Further, the frame of the processing apparatus needs to have high rigidity (Young's modulus). As described above, in the processing apparatus, the frame supports the work stage. For example, the work stage frequently repeats successive movements in step-and-repeat for dividing and exposing a region of the substrate or in drilling processing for forming a large number of through holes in the substrate. Therefore, if the work stage is supported by a frame with low rigidity, the frame vibrates greatly due to the successive movement of the work stage, and the time until the vibration of the frame stops, that is, the time until the next exposure or processing is performed becomes long. . As a result, the processing time of the workpiece becomes long, and the productivity of the apparatus is lowered.
Furthermore, if the rigidity of the frame is low, the frame is weak against external vibrations and is likely to sway. For this reason, the processing accuracy may be deteriorated.

In addition, as a condition of the frame member, it is also important that the density is small so that even a large apparatus is relatively light. As the weight increases, the cost associated with the device increases, for example, the floor of the factory where the device is installed must be reinforced.
As described above, it is desirable that the frame of the processing apparatus has characteristics such as high rigidity (Young's modulus) and low thermal expansion coefficient and density. As a material satisfying these conditions, there is carbon fiber reinforced plastic (CFRP).
For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2017-61068) discloses that CFRP is used for an automobile frame or the like. This Patent Document 1 (Japanese Patent Laid-Open No. 2017-61068) discloses that a CFRP reinforcing material is bonded to the surface of a metal member to reinforce an automobile skeleton member while suppressing an increase in weight. Yes.

JP 2017-61068 A

The technique described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2017-61068) only discloses the use of CFRP as a reinforcing material for automobile frames, and is suitable as a frame for a processing apparatus. The material is not considered.
Although it is conceivable to use CFRP alone as a frame of the processing apparatus, in recent years, the processing apparatus is required to have very high processing accuracy, and the structure has better characteristics than the CFRP alone as the material of the frame. Is required to be used. However, in order to improve the characteristics, for example, even if CFRP and another material such as metal are combined, it is not clear how to combine them.

Therefore, an object of the present invention is to provide a structure having better characteristics as a material such as a frame of a processing apparatus, a method for manufacturing the structure, and a processing apparatus using the structure.

In order to solve the above problems, in one embodiment of the structure according to the present invention, a first material mainly composed of carbon fibers and a second material mainly composed of carbon fibers are integrated. The thermal expansion coefficient of the first material and the thermal expansion coefficient of the second material are opposite to each other, and the thickness of the second material is the thickness of the first material. Thinner than that.
Thus, the structure in which the first material mainly composed of carbon fiber and the second material mainly composed of carbon fiber are combined has a small coefficient of thermal expansion (the coefficient of thermal expansion is 0 or 0). Close) and a structure with less dimensional deformation due to temperature change than the CFRP alone. It is also possible to provide a structure having relatively high rigidity, relatively low density, and high specific rigidity. That is, as a material for a frame or the like of a processing apparatus, a structure having better characteristics than that of CFRP alone can be obtained.

Furthermore, in the above structure, the first material may be a carbon fiber reinforced plastic member.
Pitch-based CFRP has a negative thermal expansion coefficient, and PAN-based CFRP has a positive thermal expansion coefficient. Therefore, even if a material having any positive or negative thermal expansion coefficient is used as the second material, the structure in which the first material and the second material are combined has a small thermal expansion coefficient (close to 0 or 0). ) It can be a structure. That is, when a material having a positive thermal expansion coefficient is used as the second material, a pitch-based CFRP member is used as the first material, and a material having a negative thermal expansion coefficient is used as the second material. In this case, a PAN-based CFRP member may be used as the first material.
In the above structure, the second material may be a metal-based material, and the first material may be a pitch-based carbon fiber reinforced plastic member.
Pitch-based CFRP has a characteristic that the thermal expansion coefficient has a negative value and shrinks in the fiber direction when heated. On the other hand, the metal has a positive coefficient of thermal expansion. Therefore, by combining the first material, which is a pitch-based CFRP member, and the second material, the main component of which is a metal, a structure having a thermal expansion coefficient of, for example, 0 can be obtained relatively easily. It becomes. In addition, a structure in which a first material that is a pitch-based CFRP member and a second material containing a metal as a main component is combined with a structure that has higher rigidity, lower density, and higher specific rigidity than metal. can do.

Furthermore, in the above structure, the metal may be iron. Thus, the metal member which has iron as a main component can be utilized as a 2nd material. In this case, the structure can be obtained relatively inexpensively.
Moreover, said structure should just have a thermal expansion coefficient below 1/10 of iron, and Young's modulus is larger than iron. As described above, a structure having a thermal expansion coefficient of 1/10 or less of iron, that is, a range of ± 1.0 × 10 ⁻⁶ and a Young's modulus larger than iron is used as a material for a frame of a processing apparatus. It is a structure having better characteristics than CFRP alone.
In the above structure, the first material and the second material may be integrated with a room temperature curable resin. In this case, the first material and the second material can be integrated while suppressing the residual stress generated by the heat treatment. Therefore, it is possible to prevent the structure from being deformed due to the residual stress.

Further, according to one aspect of the method for producing a structure according to the present invention, a step of preparing a first material mainly composed of carbon fibers and a second material mainly composed of carbon fibers, Integrating the first material and the second material, and in the preparing step, the first material and the second material are selected so that the coefficients of thermal expansion are opposite to each other. The sum of the value obtained by multiplying the coefficient of thermal expansion, Young's modulus and thickness of the first material and the value obtained by multiplying the coefficient of thermal expansion, Young's modulus and thickness of the second material is zero. The first material and the second material having the set thickness are prepared.
As a result, it is possible to manufacture a structure having a thermal expansion coefficient of 0 and less dimensional deformation due to temperature change than the CFRP alone. That is, as a material for a frame of a processing apparatus, it is possible to manufacture a structure having better characteristics than a single CFRP.
In the structure manufacturing method described above, the second material may be mainly composed of a metal.
In this way, by combining the first material mainly composed of carbon fiber and the second material mainly composed of metal, the thermal expansion coefficient is 0, the rigidity is higher than the metal, and the density is high. A small structure with high specific rigidity can be manufactured.

Moreover, the one aspect | mode of the processing apparatus which concerns on this invention is a processing apparatus which processes a workpiece | work, Comprising: The flame | frame which supports the structural member of the said processing apparatus contains one of said structures.
In this way, a processing apparatus using a structure in which a first material mainly composed of carbon fibers and a second material mainly composed of carbon fibers are combined as a frame material is used for temperature changes and external The dimensional deformation due to mechanical factors is small and a relatively lightweight processing device can be obtained.

According to the present invention, a structure having better characteristics as a material for a frame of a processing apparatus, specifically, a characteristic having a coefficient of thermal expansion smaller than that of CFRP alone while suppressing a decrease in rigidity and an increase in density is realized. can do.
The above-described objects, aspects, and advantages of the present invention, and objects, aspects, and effects of the present invention that have not been described above will be understood by those skilled in the art to implement the following invention by referring to the attached drawings and the claims. This will be understood from the following description (detailed description of the invention).

FIG. 1 is a cross-sectional view of a structure in the present embodiment. FIG. 2 is a view showing a schematic configuration of the exposure apparatus. FIG. 3 is a diagram showing a schematic configuration of the laser processing apparatus. FIG. 4 is a cross-sectional view of the structure of the comparative example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a cross-sectional view illustrating a schematic configuration of a structure 10 according to the first embodiment. In the present embodiment, the structure 10 is a CFRP structure including carbon fiber reinforced plastic (CFRP).
The structure 10 has a configuration in which a first material 11 mainly composed of carbon fibers and a second material 12 mainly composed of carbon fibers are integrated. In the present embodiment, the first material 11 is a carbon fiber reinforced plastic member (CFRP member), and the second material 12 is a metal member.

The CFRP member 11 is configured by laminating a plurality of prepregs, although not particularly illustrated. The prepreg is a sheet-like member obtained by impregnating a carbon fiber with a resin while maintaining the fiber orientation. The resin constituting the prepreg is, for example, a thermosetting epoxy resin. In addition, as resin which comprises a prepreg, thermosetting resins, such as unsaturated polyester, vinyl ester, phenol, cyanate ester, a polyimide, can also be used, for example.

In CFRP, a plurality of prepregs are laminated in a mold so that the direction of the fibers is different (for example, 20 layers), heated to about 120 ° C to 130 ° C under reduced pressure, and pressurized (crimped) And then cured. Here, the reason why the prepregs are overlapped so that the directions of the fibers are different is to enhance the strength in the in-plane direction of the prepreg isotropically.
As a substitute for the prepreg, a standard CFRP plate (for example, 5 mm UD (UNI-DIRECTION) material) having a standard dimension (standard dimension) that can be stocked at low cost can be used. The UD material is a material in which the direction of the fiber extends only in one direction.

The CFRP manufactured in this way is a material having a high strength while having a lower density (that is, lighter) than a metal material such as iron or aluminum. The CFRP member 11 is a member obtained by cutting the completed CFRP into a desired size.
CFRP is classified into a PAN system using polyacrylonitrile as a raw material and a pitch system using coal tar pitch or petroleum pitch as a raw material, depending on the starting material. The CFRP constituting the CFRP member 11 in the present embodiment is a pitch-based CFRP.

The metal member 12 is formed integrally with the surface (first surface) 11 a of the CFRP member 11. This embodiment demonstrates the case where the metal member 12 is comprised with iron. Further, the thickness D2 of the metal member 12 is set to be thinner than the thickness D1 of the CFRP member 11. Here, the “thickness” is the thickness of the member in the direction orthogonal to the surface 11 a of the CFRP member 11.
The metal member 12 may be formed by arranging a plurality of metal wires in parallel on the surface 11a of the CFRP member 11 in a planar shape.
The structure 10 can have a configuration in which the CFRP 11 and the metal member 12 are bonded together with an adhesive (not shown). The adhesive can be made of, for example, a room temperature curable resin. However, the kind of adhesive is not limited to the above.

The CFRP member 11 is composed of a carbon fiber as a main component and a curing agent (resin) as a subcomponent. Therefore, the structure 10 may be formed by integrating only the carbon fiber that is the main component of the CFRP member 11 and the metal member 12 with a curing agent that is a subcomponent of the CFRP member 11 as a molding material.

Hereinafter, an example of the manufacturing method of the structure 10 in the present embodiment will be described.
First, the CFRP member 11 is prepared by cutting out the completed CFRP to a required size. In addition, a metal member 12 having the same size as the surface 11a of the CFRP member 11 is prepared. At this time, the thicknesses of the CFRP member 11 and the metal member 12 are set by methods described later.
Next, a liquid room temperature curable resin is applied to the surface 11a of the CFRP member 11, and the metal member 12 is disposed thereon and cured at room temperature without heating. At this time, for example, a CFRP member 11 and a metal member 12 are disposed in a container so that bubbles do not enter the resin layer, and a liquid resin is formed while evacuating the gap between the CFRP member 11 and the metal member 12. And then released into the atmosphere.

In this way, the CFRP member 11 and the metal member 12 are integrated, and the structure 10 is manufactured. The structure 10 can be used for a frame of a processing apparatus, for example.
Here, the processing apparatus includes, for example, an exposure apparatus that exposes a pattern such as a circuit on a semiconductor substrate or a printed board, and a laser processing apparatus that performs cutting and drilling by irradiating the substrate with a laser. Further, a stage apparatus used as a part of the configuration of the exposure apparatus or the laser processing apparatus can be included in the processing apparatus. The stage device is a device that holds and moves a workpiece such as the substrate described above.

FIG. 2 is a view showing a schematic configuration of the exposure apparatus.
An exposure apparatus 200 shown in FIG. 2 is a projection exposure apparatus that exposes a workpiece. Here, the workpiece is a silicon workpiece, a printed substrate, a glass substrate for a liquid crystal panel, or the like, and is a workpiece having a resist film coated on the surface thereof.

The exposure apparatus 200 includes a light irradiation unit 21, a mask 22, a projection lens 23, a work stage 24, and a frame 25.
The light irradiation unit 21 includes a lamp 21a that is an exposure light source that emits light including ultraviolet rays, and a mirror 21b that reflects light from the lamp 21a. The lamp 21a and the mirror 21b are accommodated in the lamp house 21c. In addition, although the case where the light source of the light irradiation part 21 is the lamp | ramp 21a is demonstrated here, LED, a laser, etc. may be sufficient as a light source.

A pattern such as a circuit pattern that is exposed (transferred) to the workpiece is formed on the mask 22. The exposure light from the light irradiation unit 21 is irradiated onto the work held by the work stage 24 via the mask 22 and the projection lens 23, and the pattern formed on the mask 22 is projected onto the work and exposed.
The frame 25 supports main members of the exposure apparatus 200 such as the light irradiation unit 21, the mask 22, the projection lens 23, and the work stage 24. These main members are held in a predetermined position by the frame 25 in a horizontal state.

FIG. 3 is a diagram showing a schematic configuration of the laser processing apparatus.
A laser processing apparatus 300 illustrated in FIG. 3 includes a laser emitting unit 31, a work stage 32, and a frame 33.
The laser emitting unit 31 emits a laser in the direction indicated by the arrow in the figure. The laser beam from the laser emitting unit 31 is irradiated onto the workpiece held by the workpiece stage 32, and processing such as cutting and drilling of the workpiece is performed.
The frame 33 supports main members of the laser processing apparatus 300 such as the laser emitting unit 31 and the work stage 32. These main members are held in a predetermined position by the frame 33 in a horizontal state.

Each frame of the processing apparatus supports main members that are appropriately positioned. Therefore, when the temperature of the place where the processing device is placed changes and the frame expands and contracts due to thermal expansion, the position of the main member supported by the frame changes, and the processing accuracy decreases. Furthermore, it is conceivable that there may be problems that the desired position cannot be exposed and laser processing (drilling or cutting) cannot be performed.
As a countermeasure, the environment in the factory where the processing equipment is installed is managed so that the temperature is always constant, and the temperature is controlled by putting each equipment in a constant temperature booth. ing.

However, even if the environment is managed as described above, if the processing apparatus operates, it is inevitable that the apparatus itself generates heat. For example, if the work stage moves, heat is generated from the drive unit such as a motor, and if it is a laser processing device, heat is generated in the part of the work that is processed (hole drilling or cutting). To do. In the case of an exposure apparatus, when light passes through the projection lens, the projection lens portion generates heat by the light being absorbed by the lens and the lens barrel that holds the lens.
If the frame is made of a material that is likely to thermally expand, the frame expands and contracts due to the heat generated by the apparatus itself as described above, causing a reduction in processing accuracy. Therefore, as a material of the frame of the processing apparatus, a material having a thermal expansion coefficient as small as possible, for example, a material having a thermal expansion coefficient of 1/10 or less (preferably 0) with respect to a metal such as iron is desired.

Further, the frame of the processing apparatus needs to have high rigidity (Young's modulus). As described above, in the processing apparatus, the frame supports the work stage. For example, the work stage frequently repeats successive movements in step-and-repeat for dividing and exposing a region of the substrate or in drilling processing for forming a large number of through holes in the substrate.
Therefore, when the work stage is supported by a frame with low rigidity, the time until the vibration of the frame stops after the stage moves and stops increases, the work processing time becomes longer, and the productivity of the equipment decreases. Resulting in. In addition, if the frame has low rigidity, it is weak against vibration from the outside and easily sways. This also causes the processing accuracy to deteriorate.
Therefore, as the material of the frame of the processing apparatus, a material having as high a rigidity as possible, for example, a material having a higher rigidity than a metal such as iron is desired.

Furthermore, it is important that the frame of the processing apparatus has a small density so that even a large apparatus is relatively light. When the weight of the device increases, the cost associated with the device increases, for example, the floor of the factory where the device is installed must be reinforced.
That is, it is desirable that the material (structure) constituting the frame of the processing apparatus has the following three characteristics.
(1) The coefficient of thermal expansion (CTE) is close to 0 (there is little dimensional deformation due to temperature change).
(2) The rigidity is high, that is, the Young's modulus is large (bending, bending, and distortion hardly occur, that is, there is little dimensional deformation due to external factors).
(3) The density is small (even a large apparatus is relatively light).

CFRP is a material that satisfies these conditions. Although it is conceivable to use CFRP alone as a frame of the processing apparatus, in recent years, extremely high processing accuracy is required for the processing apparatus, and the structure of the frame has better characteristics than the CFRP alone. It is required to use the body.

Therefore, the present inventor, as a structure capable of drawing out better performance as a frame of a processing apparatus, a first material mainly composed of carbon fiber and a second material mainly composed of metal other than carbon fiber, for example. We researched the structure that combined with. And this inventor discovered the reference | standard and calculation formula which are easy to understand for making said structure. This point will be described in detail below.

CFRP was used as the first material mainly composed of carbon fiber. CFRP is classified into those composed of pitch-based CFRP and those composed of PAN (Polyacrylonitrile) -based CFRP.
Table 1 shows rough values of pitch-based CFRP and PAN-based CFRP, and, as a comparative example, iron thermal expansion coefficient (CTE), Young's modulus, density, and specific rigidity. In Table 1, the unit of specific rigidity is abbreviated as “GPa”.

The thermal expansion coefficient of iron is the largest in Table 1, and CFRP is about 1/10 of the pitch PAN system compared to iron. Thus, it can be seen that CFRP has less dimensional deformation due to temperature change than iron.
Further, Young's modulus is twice that of pitch-based CFRP than that of iron, but PAN-based CFRP is about ½ of iron. That is, pitch-based CFRP has higher rigidity than iron, but PAN-based CFRP has lower rigidity than iron. Furthermore, it can be seen that the density of CFRP is about ¼ that of iron, and that the density is considerably lighter than iron.
The specific rigidity is a value obtained by dividing Young's modulus by density. The larger the value, the greater the rigidity per unit density, in other words, “light and strong”. If there is a limit to the size of the device or the load capacity of the floor, it is advantageous to use a material with a large value.

In a processing apparatus, the most important issue in performing highly accurate processing is to minimize dimensional deformation due to temperature changes. In other words, the smaller the thermal expansion coefficient (the closer to 0) the better for the frame of the processing apparatus. Both pitch-based CFRP and PAN-based CFRP have a smaller thermal expansion coefficient than iron but are not zero.
Therefore, first, a combination of materials that brings the thermal expansion coefficient of the structure close to 0 is considered. In the present embodiment, by selecting two materials whose signs of thermal expansion coefficient are opposite to each other, the thermal expansion coefficient of the structure in which the two materials are combined approaches 0.

In the case of the three materials shown in Table 1, the combinations in which the signs of the thermal expansion coefficients are reversed are the combination of pitch-based CFRP and PAN-based CFRP and the combination of pitch-based CFRP and iron. Accordingly, it is considered that the structure using a combination of pitch-based CFRP and PAN-based CFRP and the structure using a combination of pitch-based CFRP and iron can have a coefficient of thermal expansion of zero.

Next, let us consider the distribution (ratio) between the two materials to make the coefficient of thermal expansion of the structure obtained by combining the two selected materials zero.
First, for the first material and the second material, the products of the thermal expansion coefficient and Young's modulus are calculated, and the ratios are obtained by comparing them. And the thickness of both is set according to the ratio.

For example, in the case of a combination of pitch-based CFRP and PAN-based CFRP, the product (A) of the value of thermal expansion coefficient and Young's modulus of pitch-based CFRP and the product of the value of thermal expansion coefficient and Young's modulus of PAN-based CFRP. (B) can be calculated as follows.
A = −1.5 × 10 ⁻⁶ × 400 = −600 × 10 ⁻⁶ (1)
B = 0.5 × 10 ⁻⁶ × 120 = 60 × 10 ⁻⁶ (2)
When the absolute values of the product A and the product B calculated by the above equations (1) and (2) are compared, A is 12 times B. Therefore, the thickness of the CFRP member using the PAN-based CFRP corresponding to B (PAN-based CFRP member) is 10 times that of the CFRP member using the pitch-based CFRP corresponding to A (pitch-based CFRP member). If bonded together, the thermal expansion coefficient of the structure can be made zero.

FIG. 4 is a view showing a structure 10A in which the pitch-based CFRP member 11 and the PAN-based CFRP member 13 are combined. If the thickness D1 of the pitch CFRP member 11 is 100 μm, the thickness D3 of the PAN CFRP member 13 is 1000 μm.
With the structure as described above, the structure 10A having a small thermal expansion coefficient (zero in calculation) can be formed.
Further, the density MA of the structure 10A is 1.78 g / cm ^3, which is very light as compared with iron, as determined from the following equation.
MA = (1.6 g / cm ³ × 100 μm + 1.8 g / cm ³ × 1000 μm) / (100 μm + 1000 μm) = 1.78 g / cm ³ (3)
Also, the specific rigidity HA of the structure 10A is 71 Gpa · cm ³ / g, which is larger than iron, as can be obtained from the following equation.
HA = 127 GPa / 1.78 g / cm ³ = 71 Gpa · cm ³ / g (4)

However, the structure 10A shown in FIG. 4 has a problem with respect to rigidity. The Young's modulus (rigidity: G1) of the structure 10A is 127 GPa as determined from the following equation. This value is smaller than the Young's modulus (200 GPa) of iron.
G1 = (400 GPa × 100 μm + 100 GPa × 1000 μm) / (100 μm + 1000 μm) = 127 GPa (5)
That is, it can be said that the combination of the pitch-based CFRP member 11 and the PAN-based CFRP member 13 is a combination that impairs the advantage of the pitch-based CFRP having a large Young's modulus (400 GPa).

Next, regarding the structure 10B in which pitch-based CFRP and iron are combined, the distribution (ratio) of two materials will be considered. The product (A) of the value of the thermal expansion coefficient and Young's modulus of the pitch-based CFRP is −600 × 10 ^{−6 as} shown in the above equation (1), and the product of the value of the thermal expansion coefficient of iron and the Young's modulus ( C) is 2000 × 10 ^{−6 as} shown in the following formula (6).
C = 10 × 10 ⁻⁶ × 200 = 2000 × 10 ⁻⁶ (6)
When the absolute values of the product A and the product C calculated by the above equations (1) and (6) are compared, A is 1/3 of C. Therefore, if the thickness of the member (metal member) using iron corresponding to C is 1/3 of the pitch-based CFRP member corresponding to A and bonded together, the coefficient of thermal expansion of the structure is reduced to zero. be able to.

A structure in which a pitch-based CFRP member and a metal member are combined is shown in FIG. In the structure 10 shown in FIG. 1, if the thickness D1 of the pitch-based CFRP member 11 is 100 μm, the thickness D2 of the metal member 12 is about 33 μm.
By adopting the structure as described above, the structure 10 having a small thermal expansion coefficient (zero in calculation) can be made.

Further, when the Young's modulus (rigidity: G2) of the structure 10B is calculated, it becomes 350 GPa as shown in the following equation.
G2 = (400 GPa × 100 μm + 200 GPa × 33 μm) / (100 μm + 33 μm) = 350 GPa (7)
This value is 1.75 times the Young's modulus (200 GPa) of iron. If the Young's modulus is larger than that of iron, it is desirable as a material for the frame of the processing apparatus.
Furthermore, the overall thickness can be reduced to about 1/10 of the structure 10A in which the pitch-based CFRP member 11 and the PAN-based CFRP member 13 shown in FIG. 4 are combined.

Further, the density (MB) of the structure 10B is larger than that of a single CFRP because iron is used. However, since the iron thickness can be reduced as described above, the density MB is about 3.16 g / cm ³ as shown in the following formula, which is less than half that of the iron density (7.9 g / cm ³ ). be able to.
MB = (1.6 g / cm ³ × 100 μm + 7.9 g / cm ³ × 33 μm) / (100 μm + 33 μm) = 3.16 g / cm ³ (8)
Thus, if the thickness of a member (metal member) using a material with a high density out of the two materials to be combined is smaller than the thickness of a member (CFRP member) using a material with a low density, it is obtained. An increase in the density of the structure to be obtained can be suppressed.
Furthermore, the specific rigidity HB of the structure 10B is 111 Gpa · cm ³ / g as determined from the following equation, which is larger than that of iron and the structure 10A described above.
HB = 350 GPa / 3.16 g / cm ³ = 111 Gpa · cm ³ / g (9)
Thus, by combining the CFRP member and the metal member, a structure having a higher specific rigidity (lighter and stronger) than the metal member to be used can be realized.

As described above, by combining the first material mainly composed of carbon fiber and the second material mainly composed of metal, the coefficient of thermal expansion is small (the calculated value is 0), rigidity, and specific rigidity. It is possible to produce a lightweight and tough structure that is both higher than metal and suppressed in density increase. Here, as the first material and the second material, materials having positive and negative thermal expansion coefficients that are opposite to each other are selected. And, the sum of the value obtained by multiplying the thermal expansion coefficient, Young's modulus and thickness of the first material and the value obtained by multiplying the thermal expansion coefficient, Young's modulus and thickness of the second material is zero. The thickness of these two materials is set.
If such a structure is used as the material of the frame of the processing apparatus, a lightweight processing apparatus with little dimensional deformation due to temperature change and external factors can be realized.

The structure manufactured as described above has a structure in which the first material and the second material, whose positive and negative thermal expansion coefficients are opposite to each other, are integrated, and the thickness of the second material is the first. It is set thinner than the thickness of one material.
Here, the first material can be a pitch-based CFRP member. The pitch-based CFRP member has a thermal expansion coefficient of −1.2 × 10 ⁻⁶ to −1.5 × 10 ⁻⁶ and has a negative thermal expansion coefficient. On the other hand, the metal has a positive coefficient of thermal expansion. Therefore, by combining the first material, which is a pitch-based CFRP member, and the second material, the main component of which is a metal, it is possible to easily obtain a structure having a thermal expansion coefficient closer to 0 than that of CFRP alone. it can.

Also, the first material can be a CFRP member as described above. Thus, a CFRP member combining carbon fiber and resin can be used as the first material. Therefore, the structure can be easily obtained with a simple structure in which the CFRP member and the second material mainly containing metal are bonded together.

Furthermore, the metal member can be made of iron. As described above, the structure can be provided at a low cost by using a relatively inexpensive metal.
In addition, by combining iron, which has been generally used as a frame of a processing apparatus, with CFRP, the thermal expansion coefficient is much smaller than that of iron (calculated value is 0), and the rigidity is also made of carbon fiber. Utilizing the characteristics, it is possible to obtain a light body with a higher specific rigidity, which is lighter and has a density much lower than that of iron.

Furthermore, the first material and the second material can be integrated with a room temperature curable resin. Since the room temperature curable resin does not require heating at the time of curing, the residual stress caused by heating does not occur in the resin layer after formation. For this reason, it is possible to appropriately suppress the deformation of the structure due to the residual stress.
The room temperature curable resin may be a room temperature curable epoxy resin. The room temperature curing type epoxy resin is used for bonding and solidifying carbon fibers in CFRP, and has a track record as an adhesive that does not impair the characteristics of carbon fibers. Furthermore, since an epoxy resin is a general resin and relatively inexpensive, the structure can be provided at a low cost.

As described above, in the present embodiment, when manufacturing a structure in which the first material and the second material are combined, the first material and the second material are selected by a very simple procedure. The distribution (thickness) between the two can be set. Therefore, it is possible to easily and appropriately obtain a structure having a smaller coefficient of thermal expansion than that of a single carbon fiber and a rigidity higher than that of a metal such as iron, a lower density, and a higher specific rigidity. And, by using the structure as described above as a frame of the processing apparatus, it is possible to realize a light processing apparatus with little dimensional deformation due to temperature change and external factors.

(Modification)
In the above-described embodiment, the case where the structure 10 is used as a frame of a processing apparatus has been described. However, the present invention is not limited to the above. The structure 10 has the characteristics that the coefficient of thermal expansion is 0, the rigidity is high, the weight is relatively light, and the specific rigidity is high. Therefore, by utilizing these characteristics, the structure 10 may be used as a material for a component of a large apparatus that requires strict dimensional stability in an environment where a temperature change or the like may occur.

Moreover, in the said embodiment, although the case where the thickness of the CFRP member 11 and the metal member 12 was set so that the thermal expansion coefficient of the structure 10 might be set to 0 was demonstrated, a thermal expansion coefficient is a value close | similar to 0. If it is. Specifically, if the thermal expansion coefficient is 1/10 or less of iron (10 × 10 ⁻⁶ ), that is, within a range of ± 1.0 × 10 ⁻⁶ , it is desirable as a material for the frame of the processing apparatus.
Furthermore, in the said embodiment, although the case where the material which has a metal as a main component was demonstrated about the 2nd material, it is not limited to this. As the second material, a material whose thermal expansion coefficient is opposite to that of the first material may be selected. If a carbon fiber reinforced plastic member (CFRP) is used as the first material, the pitch-based CFRP has a negative thermal expansion coefficient and the PAN-based CFRP has a positive thermal expansion coefficient as described above. Yes. Therefore, even if a material having any positive or negative thermal expansion coefficient is used as the second material, the first material that makes the thermal expansion coefficient zero when combined can be selected.
Moreover, in the said embodiment, although the case where iron was used as a metal which comprises the metal member 12 was demonstrated, it is not limited to iron. The metal has a thermal expansion coefficient of 1/10 or less of iron and a Young's modulus larger than iron (200 GPa) when combined with a first material (for example, CFRP member) mainly composed of carbon fiber. Any material that can realize the structure may be used, and for example, titanium may be used. Note that the material of the frame of the processing apparatus preferably has a Young's modulus larger than that of iron, and a practical value is, for example, 200 GPa to 400 GPa.

Although specific embodiments have been described above, the embodiments are merely examples and are not intended to limit the scope of the present invention. The devices and methods described herein can be embodied in forms other than those described above. In addition, omissions, substitutions, and changes can be made as appropriate to the above-described embodiments without departing from the scope of the present invention. Such omissions, substitutions, and modifications are included in the scope of the claims and their equivalents, and belong to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Structure (CFRP structure), 11 ... CFRP member (pitch type), 12 ... Metal member, 13 ... CFRP member (PAN type), 21 ... Light irradiation part, 22 ... Mask, 23 ... Projection lens, 24 ... Work stage, 25 ... frame, 31 ... laser emitting part, 32 ... work stage, 33 ... frame, 200 ... exposure device (processing device), 300 ... laser processing device

Claims

Having a structure in which the first material mainly composed of carbon fiber and the second material mainly composed of other than carbon fiber are integrated,
The coefficient of thermal expansion of the first material and the coefficient of thermal expansion of the second material are opposite in sign.
The thickness of said 2nd material is thinner than the thickness of said 1st material, The structure characterized by the above-mentioned.
The structure according to claim 1, wherein the first material is a carbon fiber reinforced plastic member.
2. The structure according to claim 1, wherein the second material contains a metal as a main component.
The structure according to claim 3, wherein the first material is a pitch-based carbon fiber reinforced plastic member.
The structure according to claim 3 or 4, wherein the metal is iron.
The structure according to any one of claims 1 to 5, wherein a thermal expansion coefficient is one tenth or less of iron and Young's modulus is larger than iron.
The structure according to any one of claims 1 to 6, wherein the first material and the second material are integrated by a room temperature curable resin.
Preparing a first material mainly composed of carbon fiber and a second material mainly composed of other than carbon fiber;
Integrating the first material and the second material,
In the step of preparing,
Select the first material and the second material that the thermal expansion coefficient is opposite to each other,
The sum of the value obtained by multiplying the coefficient of thermal expansion, Young's modulus and thickness of the first material and the value obtained by multiplying the coefficient of thermal expansion, Young's modulus and thickness of the second material is zero. The manufacturing method of the structure characterized by preparing said 1st material and said 2nd material with which said thickness was set.
9. The method of manufacturing a structure according to claim 8, wherein the second material contains a metal as a main component.
A processing device for processing a workpiece,
The processing apparatus according to claim 1, wherein a frame that supports a constituent member of the processing apparatus includes the structure according to claim 1.