JP2008034766A - Suction member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a suction member that can prevent a plate-like body from being distorted that is to be sucked and satisfy its predetermined dimensional accuracy. <P>SOLUTION: A suction port 1 is a suction member for sucking a plate-like body, wherein it has a suction portion 110 having a suction plane 111 for sucking the plate-like body, a supporting part 120 for supporting the suction portion 110 and fixing it to a predetermined place, and a joining section 130 for joining the suction portion 110 and the supporting part 120. Flatness of the suction portion 110's suction plane 111 is 0.1 μm or more, and 3 μm or less, and the suction member is made of ceramic. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention generally relates to an adsorbing member, and specifically holds a photomask (reticle) in an exposure apparatus used in a lithography process for manufacturing a semiconductor element, a liquid crystal display element, a thin film magnetic head, and the like. The present invention relates to an adsorbing member as a holding means.

  Conventionally, a holding means for holding a photomask (reticle) is incorporated in an exposure apparatus used in a lithography process. Various means have been proposed for the holding means in order to enable exposure without distorting the photomask or to eliminate the bending of the photomask.

  For example, in the exposure apparatus described in Japanese Patent Application Laid-Open No. 2006-41302 (Patent Document 1), generation of distortion on the original plate surface during clamping of an original plate such as a photomask can be prevented, and exposure can be performed without distorting the original plate. Therefore, the first original holding part provided with the original holding surface for holding and positioning on the photomask as the original and the photo at different positions with respect to the reticle holding surface of the first original holding part There is provided a second original holding portion that contacts and holds the mask and is supported so as to be relatively displaceable with respect to the first original holding portion. As described above, the original holding surface of the original holding member for positioning the holding surface is elastically deformed with respect to the first original holding portion and the state of the foreign matter or the original surface while generating a suction force on the holding surface. However, by providing a second original holding surface that is clamped by suction, the distortion of the original surface due to foreign matter is generated, and the difference in flatness between the original surface and the original holding surface is caused by the difference in flatness between the original surface and the original surface. It prevents the occurrence of distortion.

Further, for example, in Japanese Patent Laid-Open No. 2006-41012 (Patent Document 2), the bending caused by the thermal deformation of a plate-like object such as a mask or a substrate that is sucked and held at a plurality of locations is detected by, for example, irradiation with illumination light. There is described an exposure apparatus for allowing the mask deflection to be eliminated while maintaining the reference position and posture of the plate-like object. In this exposure apparatus, when performing an exposure process, all of the suction ports suck and hold the mask. When the exposure process is interrupted, at least one of the plurality of suction ports holding the mask is put into a suction state, and the remaining suction ports At least one of them is released to eliminate the bending of the mask.
JP 2006-41302 A JP 200641012 A

  However, in Japanese Patent Application Laid-Open No. 2006-41302 (Patent Document 1), as a master holding surface of a master holding member for positioning a holding surface, a first master holding portion and a foreign substance while generating a suction force with respect to the holding surface. It has been proposed to provide a second original holding surface that is suction clamped by following along the elastic deformation of the original surface, and the material suitable for this original holding member is disclosed in the above publication. Is not disclosed. In order to realize such an original holding member, not only an elastic material is selected, but a predetermined accuracy is required for the original holding surface of the original holding member. Is not disclosed, it is difficult to achieve the effects as disclosed in the above publication.

  In Japanese Patent Laid-Open No. 2006-41012 (Patent Document 2), at the time of interruption of exposure processing, at least one of a plurality of suction ports holding a mask is brought into a suction state, and at least one of the remaining suction ports is released. Although it has been proposed to eliminate the bending of the mask, there is a problem that the fixation of the mask becomes unstable. In order to firmly fix the mask, it is conceivable to increase the suction area of each suction port, but there is a problem that the apparatus and the mask are increased in size.

  Furthermore, even during the exposure process, the mask is thermally deformed over time by the irradiation light. However, if the bending caused by this thermal deformation is to be eliminated by the method proposed in the above publication, the mask fixing becomes unstable. There's a problem. For this reason, it is difficult to eliminate the bending that occurs during the exposure process.

  Accordingly, an object of the present invention is to provide a suction member that can prevent the occurrence of distortion in a plate-like body as a suction target and can satisfy a predetermined dimensional accuracy.

  An adsorbing member according to the present invention is an adsorbing member for adsorbing a plate-like body, and has an adsorbing portion having an adsorbing surface for adsorbing the plate-like body, and supports the adsorbing portion and is fixed at a predetermined position. And a connecting portion that connects the suction portion and the support portion, the flatness of the suction surface of the suction portion is 0.1 μm or more and 3 μm or less, and the suction member is made of ceramics.

  In the adsorbing member of the present invention, since the flatness of the adsorbing surface that adsorbs the plate-like body is processed within a predetermined range, the adsorbed plate is formed by elastically deforming the connecting portion made of ceramics. It is possible to effectively prevent the occurrence of distortion in the body.

  In the adsorbing member of the present invention, the bending strength of the ceramic is preferably 300 MPa or more and 2000 MPa or less.

  In the adsorbing member of the present invention, the Young's modulus of the ceramic is preferably 100 GPa or more and 400 GPa or less.

Furthermore, in the adsorbing member of the present invention, it is preferable that the linear thermal expansion coefficient of the ceramic is 0.01 × 10 ⁻⁶ / K or more and 10 × 10 ⁻⁶ / K or less.

  In the suction member of the present invention, the surface roughness Ra of the suction surface of the suction member with which the plate-like body abuts is preferably 0.005 μm or more and 0.1 μm or less.

  According to the adsorbing member of the present invention, it is possible to effectively prevent the occurrence of distortion in the adsorbed plate-like body.

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

  FIG. 1 is a perspective view showing an adsorbing member as one embodiment of the present invention. FIG. 2 is a side view showing an adsorbing member as one embodiment of the present invention.

  As shown in FIGS. 1 and 2, the suction port 1 as a suction member for sucking a plate-like body such as a mask supports the suction portion 110 having a suction surface for sucking the plate-like body, and the suction portion 110. And it is comprised from the support part 120 for fixing to the fixed surface 201 of the predetermined location 200, and the connection part which connects the adsorption | suction part 110 and the support part 120, and is formed from ceramics. The suction portion 110 is formed on both sides of the suction surface 111 with which the plate-like body abuts, a recess 114 formed in the suction surface 111, a suction hole 112 formed in the center of the recess 114, and the suction hole 112. And a pin 113.

  The flatness of the suction surface 111 is controlled to be 0.1 μm or more and 3 μm or less with a flatness defined in accordance with JIS B 0621. When the flatness exceeds 3 μm, a gap is generated between the plate-like body such as a mask and the suction surface 111, so that the suction force is reduced and it becomes difficult to sufficiently hold the plate-like body such as the mask. . If the flatness is less than 0.1 μm, the processing cost for controlling the flatness is significantly increased, but the effect of increasing the attractive force cannot be obtained. Note that the suction member is repeatedly used in repeated exposure processes that cause thermal deformation of the plate body such as a mask, and repeatedly moving and stopping the stage where the plate body such as the mask and the suction member are installed. In order to maintain a suction force that can sufficiently suppress the displacement (slip) between the plate-like body such as a mask and the suction member, the flatness of the suction surface 111 is preferably 1 μm or less. .

  In the suction port 1 configured as described above, since the flatness of the suction surface 111 that sucks the plate-like body is controlled within a predetermined range, the connecting portion 130 made of ceramics is elastically deformed. Thus, the occurrence of distortion in the adsorbed plate-like body can be effectively prevented.

  The surface roughness of the suction surface 111 with which the plate-like body abuts in order to increase the suction force is preferably 0.005 μm or more and 0.1 μm or less in terms of Ra specified in accordance with JIS B 0601, and 0.05 μm More preferably, it is as follows. If the surface roughness exceeds 0.1 μm, the suction force decreases due to the gap formed between the plate-like body such as a mask and the suction surface 111, and the interface between the plate-like body and the suction member in the above-described repeated use. There is a risk that slippage may occur and the position of a plate-like body such as a mask may be displaced. If the surface roughness is less than 0.005 μm, the processing cost for controlling the surface roughness is significantly increased, but the effect of increasing the adsorption force cannot be obtained.

  Further, in order to suppress deformation or distortion of a plate-like body such as a mask during suction, the parallelism of the suction surface 111 is JIS with respect to the flatness of the fixed surface 201 with which the support surface 121 of the support portion 120 abuts. The parallelism defined in accordance with B 0621 is preferably 0.2 μm or more and 3 μm or less, and more preferably 1.5 μm or less. Since a plate-like body such as a mask is adsorbed and fixed by a plurality of adsorbing members, if this parallelism exceeds 3 μm, the deflection of the plate-like body may be increased beyond an allowable amount. Processing the parallelism to less than 0.2 μm is not practical because not only the processing technique is difficult, but also processing costs increase.

The suction port 1 is made of ceramics, but it is preferable to use ceramics having a small thermal expansion difference from a plate-like body such as a mask. If the difference in thermal expansion is large, the thermal deformation of the plate-like body such as the mask that occurs during the exposure process tends to cause the displacement of the plate-like body such as the mask, so the linear thermal expansion of the ceramic forming the suction port 1 The coefficient is 0.01 × 10 ⁻⁶ / K to 10 × 10 ⁻⁶ / K in terms of linear thermal expansion coefficient (average value from room temperature to 800 ° C.) defined in accordance with JIS R 1618. Preferably, it is 5 × 10 ⁻⁶ / K or less. For example, alumina, silicon carbide, silicon nitride, or the like is preferably used as the ceramic. When the linear thermal expansion coefficient exceeds 10 × 10 ⁻⁶ / K, the difference in thermal expansion from a plate-like body such as a mask becomes large. Therefore, when the temperature of the plate-like body rises, Slippage occurs between the two and the plate-like body such as a mask is likely to be displaced. In order to make the linear thermal expansion coefficient less than 0.01 × 10 ⁻⁶ / K, it is generally necessary to include a particle dispersion material having a low thermal expansion inside the ceramics. These characteristics, for example, strength may be reduced, and durability may be reduced.

  In order to control the heat input / output from a plate-like body such as a mask placed on the suction surface 111 of the suction port 1, the thermal conductivity of the ceramic forming the suction port 1 conforms to JIS R 1611. Therefore, it is preferable that the thermal conductivity is 1 W / mK or more and 200 W / mK or less. If the thermal conductivity is less than 1 W / mK, the heat conduction is too low and the effect of removing heat from the plate-like body is poor. Therefore, the temperature rise of the plate-like body continuously proceeds during use, and the plate-like body is not thermally deformed. There is a risk of progressing gradually. If the thermal conductivity exceeds 200 W / mK, the outflow of heat from the adsorption port 1 becomes large, so that the in-plane temperature distribution of the plate-like body becomes large and the thermal deformation becomes non-uniform in the plane. It may be difficult to eliminate the bending of the plate-like body due to the elastic deformation.

  In order to effectively prevent the occurrence of distortion in the plate-like body adsorbed by the adsorption port 1, it is necessary for the connecting portion 130 made of ceramics to be elastically deformed. In order for this elastic deformation to be repeated, the ceramic forming the adsorption port 1 needs to have a certain strength or more. The bending strength of the ceramic is preferably 3 MPa or more and 2000 MPa or less, more preferably 600 MPa or more, and more preferably 1150 MPa or more as a three-point bending strength defined in accordance with JIS B 1601. When the bending strength is less than 300 MPa, the durability of the suction port 1 is lowered. When the bending strength exceeds 2000 MPa, the durability of the suction port 1 can be further increased. However, in order for the bending strength to exceed 2000 MPa, it is necessary to remove internal defects of the ceramic, and the manufacturing cost for that is high. Therefore, higher bending strength is not practical.

  In order to ensure the wear resistance of the suction surface 111 of the suction port 1, the Vickers hardness of the suction surface 111 is preferably 1000 or more and 2500 or less in terms of Vickers hardness defined in accordance with JIS B 1610. The above is more preferable. When the Vickers hardness is less than 1000, wear of the adsorption surface 111 is increased. In order for the Vickers hardness to exceed 2500, ceramics must be composed of a composite material. In this case, other characteristics, for example, strength may be reduced, and durability may be reduced.

  In order to effectively prevent the occurrence of distortion in the plate-like body adsorbed by the adsorption port 1, it is necessary for the connecting portion 130 made of ceramics to be elastically deformed. In order for this elastic deformation to be repeatedly performed, the connecting portion 130 must be able to be deformed to an inclination. That is, the suction port 1 must be formed of ceramics having a Young's modulus greater than a certain value. The Young's modulus of the ceramic is preferably 100 GPa or more and 400 GPa or less as the Young's modulus specified in accordance with JIS R 1602. If the Young's modulus is less than 100 GPa, the connecting portion 130 and the suction portion 110 are too easily deformed, so that the central portion of the plate-like body such as a mask whose end is supported by the suction member becomes concave due to its own weight. The effect of preventing the deformation is reduced, and it becomes difficult to ensure the parallelism and flatness of the plate-like body with a predetermined accuracy. If the Young's modulus exceeds 400 GPa, the deformation amount of the connecting portion 130 is too small, and it becomes difficult to prevent the occurrence of distortion in the plate-like body adsorbed by the adsorption port 1.

  The shape of the connecting portion 130 may be a cylinder or a polygonal column. However, it is preferable that R processing is performed with a radius of 0.1 mm to 0.5 mm at the connecting portion between the connecting portion 130 and the suction portion 110 and the connecting portion between the connecting portion 130 and the support portion 120. In this R processing, if the radius is less than 0.1 mm, stress concentration tends to occur, and the possibility of breakage increases at the above-mentioned connecting portion. If the radius exceeds 0.5 mm, the cost for maintaining the shape of the grindstone during processing increases.

  In addition, the cross-sectional area of the connecting portion 130 is preferably 1% or more and 20% or less with respect to the entire area of the suction surface 111. If the ratio of the cross-sectional area is less than 1%, the connecting portion 130 tends to break. If the ratio of the cross-sectional area exceeds 20%, the amount of deformation of the connecting portion 130 decreases, and it becomes difficult to prevent the occurrence of distortion in the plate-like body adsorbed by the adsorption port 1.

  Furthermore, the ratio (h / d) of the height (h) of the connecting portion 130 and the thickness (d) of the suction portion 110 is preferably 0.2 or more and 1 or less. If this ratio is less than 0.2, the connecting portion 130 is difficult to deform, and it is difficult to prevent the occurrence of distortion in the plate-like body adsorbed by the adsorption port 1. If this ratio exceeds 1, the amount of deformation of the connecting portion 130 becomes too large, and it becomes difficult to ensure the parallelism and flatness of a plate-like body such as a mask with a predetermined accuracy.

  In the suction port 1 made of ceramics configured as described above, it has been conventionally difficult to control the flatness of the suction surface 111 with a predetermined accuracy.

  The suction port 1 includes not only the suction portion 110 and the support portion 120 but also a displaceable connecting portion 130 that connects the suction portion 110 and the support portion 120. If the connecting portion 130 is formed before the suction surface 111 is finished, the connecting portion 130 is deformed when the suction surface 111 is finished so that the flatness of the suction surface 111 is controlled to a predetermined accuracy. It is difficult to process.

  On the other hand, if the side surface is slit to form the connecting portion 130 after being processed by controlling the flatness of the adsorption surface 111 to a predetermined accuracy, the adsorption surface 111 is affected by the sintering strain inherent in the ceramics. The flatness of the image will deviate from the predetermined accuracy.

  Thus, with the conventional processing method, it is difficult to perform processing so that the flatness of the suction surface 111 is controlled to a predetermined accuracy.

  Therefore, the present inventor has examined and found a method capable of processing the suction surface 111 to a predetermined flatness even if the connecting portion 130 is formed before finishing the suction surface 111.

  FIG. 3 is a perspective view showing a method of processing the suction surface of the suction member as one embodiment of the present invention. FIG. 4 is a perspective view showing a jig used in the process of processing the suction surface of the suction member as one embodiment of the present invention. FIG. 5 is a plan view showing a method of processing the suction surface of the suction member as one embodiment of the present invention. FIG. 6 is a side view showing a method of processing the suction surface of the suction member as one embodiment of the present invention.

  When finishing the suction surface 111 by lapping using loose abrasive grains, as shown in FIG. 3, a wedge made of the same material as the suction port 1 is formed in the gap between the suction portion 110 and the support portion 120 from four directions. The member 300 is inserted. Then, a deformation preventing member 400 having a shape as shown in FIG. 4 is made of the same material as that of the suction port 1, and the deformation preventing member 400 is bonded to the side surfaces of the suction portion 110 and the support portion 120 as shown in FIGS. Fix with an agent. Thereafter, the wedge member 300 is extracted. In this state, the suction surface 111 is lapped. By doing in this way, the deformation | transformation at the time of a process can be prevented, and it becomes possible to process the adsorption | suction surface 111 by predetermined | prescribed flatness.

  In the use state of the suction port of the present invention, a detection unit for detecting the bending of a plate-like body such as a mask placed on the suction surface 111 of the suction port 1 and the plate-like body with respect to the suction port 1 A plurality of pressing portions that can apply the pressing load, and by adjusting the pressing pressure of the plate-like body, the deformation amount of the suction port 1 is adjusted, and the flatness of the plate-like body is always constant. You may make it keep.

  Using various ceramic materials shown in Table 1, the suction port 1 shown in FIG. 1 was produced. In the suction port 1, the suction part 110 has a width of 10 mm, a length of 30 mm, and a height of 2 mm, and the support part 120 has a width of 15 mm, a length of 60 mm, and a height of 2 mm. The connecting part 130 had a diameter of 4 mm and a height of 1 mm. The size of the recess 114 formed in the suction surface 111 is 6 mm in width, 26 mm in length, 0.05 mm in depth, and the diameter of the suction hole 112 formed in the central portion of the recess 114 is 2 mm, The pins 113 formed on both sides of the suction hole 112 had a diameter of 0.5 mm and a height of 0.05 mm.

  The manufacturing method of the adsorption port 1 using various ceramic materials is as follows. The finishing process of the suction surface 111 was performed by adopting the method shown in FIGS.

(Alumina A)
Using alumina powder with a purity of 75% or more and 90% or less and an average particle size of 1 μm or more and 5 μm or less as a raw material powder, 5% by mass of a water solvent and polyvinyl alcohol is added to this raw material powder, and pulverized and mixed with a ball mill did. Then, the slurry obtained by mixing was dried with a spray dryer and granulated. The obtained granulated powder was put into a rubber mold and pressed and hardened by cold isostatic pressing (CIP) at a pressure of 1 to 2 ton / cm ² . The molded body thus obtained was cut with an end mill. This compact was sintered at 1350-1700 ° C. for 2 hours in an air atmosphere furnace. The obtained sintered body was processed into the above predetermined shape with a surface grinding machine, a grinding center, and a blasting apparatus.

(Alumina B)
Using alumina powder having a purity of 95% or more and 99.7% or less and an average particle size of 0.5 μm or more and 2 μm or less as a raw material powder, 5% by mass of a water solvent and polyvinyl alcohol are added to the raw material powder, The mixture was pulverized and mixed with a ball mill. Then, the slurry obtained by mixing was dried with a spray dryer and granulated. The obtained granulated powder was put into a rubber mold and pressed and hardened by cold isostatic pressing (CIP) at a pressure of 1 to 2 ton / cm ² . The molded body thus obtained was cut with an end mill. This compact was sintered at 1550-1800 ° C. for 2 hours in an air atmosphere furnace. The obtained sintered body was processed into the above predetermined shape with a surface grinding machine, a grinding center, and a blasting apparatus.

(Zirconia)
Using what average particle diameter was added yttria _(Y 2 _{O 3)} powder 1μm below zirconia (ZrO ₂₎ powder or 0.1 [mu] m 5.4 wt% as a raw material powder for the raw material powder, water A solvent and polyvinyl alcohol were added in an amount of 5% by mass, and pulverized and mixed with a ball mill. Then, the slurry obtained by mixing was dried with a spray dryer and granulated. The obtained granulated powder was put into a rubber mold and pressed and hardened by cold isostatic pressing (CIP) at a pressure of 1 to 2 ton / cm ² . The molded body thus obtained was cut with an end mill. The molded body was heat-treated at 800 ° C. in an air atmosphere furnace and then sintered at 1300 to 1600 ° C. for 2 hours in the air atmosphere or in vacuum. The obtained sintered body was processed into the above predetermined shape with a surface grinding machine, a grinding center, and a blasting apparatus.

(Silicon carbide)
A material obtained by adding 0.1 to 5% by mass of boron carbide in terms of boron to silicon carbide powder having an average particle size of 0.5 μm is used as a raw material powder, and an aqueous solvent and polyvinyl butyral are added to this raw material powder. The mass% was added and pulverized and mixed with a ball mill. Then, the slurry obtained by mixing was dried with a spray dryer and granulated. The obtained granulated powder was put into a rubber mold and pressed and hardened by cold isostatic pressing (CIP) at a pressure of 1 to 2 ton / cm ² . The molded body thus obtained was cut with an end mill. This molded body was sintered by hot pressing for 1 hour while applying a pressure of 50 MPa in an argon gas atmosphere furnace. The obtained sintered body was processed into the above predetermined shape with a surface grinding machine, a grinding center, and a blasting apparatus.

(Silicon nitride A)
This raw material powder is obtained by adding 6% by mass of yttria (Y ₂ O ₃ ) powder and ₃ % by mass of alumina (Al ₂ O ₃ ) powder to silicon nitride powder having an average particle size of 0.4 μm as a raw material powder. The aqueous solvent and polyvinyl butyral were added in an amount of 5% by mass, and pulverized and mixed with a ball mill. Then, the slurry obtained by mixing was dried with a spray dryer and granulated. The obtained granulated powder was put into a rubber mold and pressed and hardened by cold isostatic pressing (CIP) at a pressure of 1 to 2 ton / cm ² . The molded body thus obtained was cut with an end mill. This molded body was heat-treated at 800 ° C. in an air atmosphere furnace and then sintered at 1600-1800 ° C. for 3 hours in a 0.5 MPa nitrogen atmosphere furnace. The obtained sintered body was processed into the above predetermined shape with a surface grinding machine, a grinding center, and a blasting apparatus.

(Silicon nitride B)
5% by mass of yttria (Y ₂ O ₃ ) powder, 3% by mass of alumina (Al ₂ O ₃ ) powder, and 1% by mass of aluminum nitride (AlN) added to silicon nitride powder having an average particle size of 0.4 μm Was used as a raw material powder, and 5% by mass of an aqueous solvent and polyvinyl butyral were added to this raw material powder, followed by pulverization and mixing with a ball mill. Then, the slurry obtained by mixing was dried with a spray dryer and granulated. The obtained granulated powder was put into a rubber mold and pressed and hardened by cold isostatic pressing (CIP) at a pressure of 1 to 2 ton / cm ² . The molded body thus obtained was cut with an end mill. The molded body was heat-treated at 800 ° C. in an air atmosphere furnace, and then sintered at 1400 to 1600 ° C. for 4 hours in a 0.1 MPa nitrogen atmosphere furnace, and further sintered at 1600 to 1800 ° C. for 2 hours. The obtained sintered body was processed into the above predetermined shape with a surface grinding machine, a grinding center, and a blasting apparatus.

(Silicon nitride C)
Silicon nitride powder having an average particle diameter of 0.4 μm, 5% by mass of yttria (Y ₂ O ₃ ) powder, ₂ % by mass of alumina (Al ₂ O ₃ ) powder, 1% by mass of aluminum nitride (AlN), magnesia ( A material added with 1% by mass of MgO) was used as a raw material powder, and 5% by mass of an aqueous solvent and polyvinyl butyral were added to the raw material powder, followed by stirring and mixing while applying ultrasonic vibration. Then, the slurry obtained by mixing was dried with a spray dryer and granulated. The obtained granulated powder was put into a rubber mold and pressed and hardened by cold isostatic pressing (CIP) at a pressure of 1 to 2 ton / cm ² . The molded body thus obtained was cut with an end mill. The molded body was heat-treated at 800 ° C. in an air atmosphere furnace, then sintered in a 0.1 MPa nitrogen atmosphere furnace at 1300 to 1500 ° C. for 2 hours, further sintered at 1500 to 1650 ° C. for 2 hours, Further, pressure sintering was performed at 1550 to 1650 ° C. for 1 hour in a 98 MPa nitrogen atmosphere furnace. The obtained sintered body was processed into the above predetermined shape with a surface grinding machine, a grinding center, and a blasting apparatus.

The linear thermal expansion coefficient [10 ⁻⁶ / K], bending strength [MPa], thermal conductivity [W / mK], Young's modulus [GPa] of the adsorption port 1 made of various ceramic materials obtained as described above. In addition, the flatness [μm], the parallelism [μm], and the surface roughness Ra [μm] of the suction surface 111, the connection portion between the connection portion 130 and the suction portion 110, and the connection portion between the connection portion 130 and the support portion 120 The “connecting portion R [mm]” was measured as a radius in the R processing applied to the portion. The measurement results are shown in Table 1.

The coefficient of linear thermal expansion [10 ⁻⁶ / K] (average value from room temperature to 800 ° C.) was measured according to JIS R 1618. The bending strength [MPa] was measured according to JIS R 1601. The thermal conductivity [W / mK] was measured according to JIS R 1611. Young's modulus [GPa] was measured according to JIS R 1601.

  The flatness [μm] and the parallelism [μm] of the suction surface 111 were measured in accordance with JIS B 0621. The parallelism was measured using a three-dimensional measuring instrument or an optical interferometer. In the measurement of parallelism, as shown in FIG. 2, the suction is performed with the support surface 121 of the support portion 120 fixed so as to contact the fixed surface 201 of the surface plate whose flatness is measured in advance as the predetermined location 200. The flatness of the surface 111 was measured with or without contact, and this flatness was defined as parallelism.

  The surface roughness Ra [μm] of the adsorption surface 111 was measured according to JIS B 0601.

Corresponding to a reticle (photomask) as a plate using four samples of the suction port 1 with the same flatness, parallelism and surface roughness of the suction surface 111 for each ceramic material. The suction ports 1 were arranged at the four corners of a quartz glass plate (size: a square with a side of 152 mm and a thickness of 6.3 mm). And in the state which adsorb | sucked the quartz glass plate with the commercially available diaphragm type vacuum pump (attainment pressure 3.3x10 < ^-3 > Pa), the heater for temperature rising was mounted on the upper surface of a quartz glass plate, room temperature and 80 degreeC. The durability test was repeated until the temperature was repeatedly increased and decreased to 1 million times.

  The results are shown in Table 1.

In the column of “initial suction force” in Table 1, “◯” indicates that the vacuum degree of the suction part 111 has reached 1 × 10 ⁻⁴ Pa, and “×” indicates that the vacuum degree of the suction part 111 is 1 × 10 ^−4. This indicates that Pa has not been reached.

  In the column of “Initial deflection” in Table 1, “◯” indicates that the parallelism of the upper surface (non-adsorption surface) of the quartz glass plate measured after adsorption was less than 5 μm, and “Δ” was measured after adsorption. It shows that the parallelism of the upper surface (non-adsorption surface) of the quartz glass plate was 5 μm or more. When an adsorption member whose initial deflection is evaluated as “Δ” is used, the exposure pattern accuracy may be lowered in a lithography process using a large-sized photomask or a high-precision lithography process.

  In the column of “Durability Test” in Table 1, “◯” indicates that the connecting portion 130 did not break at a predetermined number of repetitions during the test, and “×” indicates the connecting portion 130 at a predetermined number of repetitions during the test. Indicates that it has broken.

  In the “Slip” column of Table 1, “○” indicates that “slip” did not occur even if the predetermined number of repetitions occurred during the test, and “×” indicates “slip” at the predetermined number of repetitions during the test. "Is generated.

  Here, the occurrence of “slip” was determined as follows. A mark was placed on the surface of the quartz glass plate in order to measure the horizontal distance from an arbitrary portion of the suction part 110. Before the endurance test, the horizontal distance from the adsorbing portion 110 to the mark attached on the surface of the quartz glass plate was measured. During the durability test (at room temperature), the distance in the horizontal direction from the adsorption unit 110 to the mark attached on the surface of the quartz glass plate was measured. When the difference between the distance measured during the durability test and the distance measured before the durability test was 0.01 mm or more, it was determined that “slip” occurred.

  From Table 1, the sample No. 4 whose flatness of the adsorption surface 111 of the adsorption unit 110 is outside the scope of the present invention could not obtain a predetermined initial adsorption force and did not function as an adsorption member. It can be seen that a predetermined initial adsorption force could be obtained with the other samples.

  It should be considered that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above embodiments and examples but by the scope of claims, and is intended to include all modifications and variations within the meaning and scope equivalent to the scope of claims. .

It is a perspective view which shows an adsorption | suction member as one embodiment of this invention. It is a side view which shows an adsorption member as one embodiment of this invention. It is a perspective view which shows the processing method of the adsorption | suction surface of an adsorption | suction member as one embodiment of this invention. It is a perspective view which shows the jig | tool used in the process of the adsorption | suction surface of an adsorption | suction member as one embodiment of this invention. It is a top view which shows the processing method of the adsorption | suction surface of an adsorption | suction member as one embodiment of this invention. It is a side view which shows the processing method of the adsorption | suction surface of an adsorption | suction member as one embodiment of this invention.

Explanation of symbols

  1: suction port, 110: suction part, 111: suction surface, 120: support part, 130: connection part.

Claims (5)

An adsorbing member for adsorbing a plate-like body,
An adsorbing part having an adsorbing surface for adsorbing a plate-like body;
A support part for supporting the suction part and fixing it to a predetermined location;
A connecting portion that connects the adsorbing portion and the support portion;
The flatness of the suction surface of the suction part is 0.1 μm or more and 3 μm or less,
Adsorption member made of ceramics.   The adsorbing member according to claim 1, wherein the ceramic has a bending strength of 300 MPa to 2000 MPa.   The adsorption member according to claim 1 or 2 whose Young's modulus of said ceramics is 100 GPa or more and 400 GPa or less. The adsorption | suction member of any one of Claim 1- Claim 3 whose linear thermal expansion coefficient of the said ceramic is 0.01 * 10 < ^-6 > / K or more and 10 * 10 < ^-6 > / K or less.   The adsorption member according to any one of claims 1 to 4, wherein a surface roughness Ra of an adsorption surface of the adsorption member with which the plate-like body abuts is 0.005 µm or more and 0.1 µm or less.

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