JP2023006065A - Ceramic joined body and method for producing the same - Google Patents

Abstract

To provide a ceramic joined body having excellent thermal conductivity, wherein a joining failure is reduced between a rear face of a joining layer and a concave portion, so that the rear face thereof and the concave portion are joined firmly.SOLUTION: A ceramic joined body according to this invention includes: a first ceramic member having a flat front face and a rear face positioned opposite to the front face; a second ceramic member having a concave portion for housing the first ceramic member; and a glassy joining layer for joining the rear face of the first ceramic member and a bottom face of the concave portion in the second ceramic member. The bottom face of the concave portion in the second ceramic member includes a groove portion and a flat portion other than the groove portion. An arithmetic average roughness of the surface of the groove part is larger than that of the surface of the flat portion. The joining layer joins at least the groove portion and the rear face.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present disclosure relates to a ceramic bonded body and a manufacturing method thereof.

2. Description of the Related Art Vacuum chucks are used to adsorb and hold objects to be adsorbed in processes such as film formation, processing, wiring formation, and inspection in the manufacturing process of semiconductor products. A vacuum chuck, for example, as shown in Patent Document 1, is a dense structure having a suction portion made of a porous body having a suction surface for holding a substrate, an element, or other object to be sucked by suction, and a concave portion for accommodating the porous body. It is formed by joining a support portion made of a solid body.

If the flatness of the concave portion is large, the gap between the suction portion and the rear surface of the suction portion becomes large when the suction portion is inserted, and a space for defective bonding is likely to occur. The presence of defective bonding causes a decrease in bonding strength, variations in the adsorption force and temperature distribution, and the like. When a vacuum chuck is used in a grinding device, a thermocompression bonding device, or the like, the suction portion is deformed by the load during pressing. As a result, the processing accuracy is lowered, or it becomes a cause of defective crimping. In order to improve the processing accuracy of an object to be adsorbed such as a wafer, the flatness of the bottom surface of the concave portion should be high.

On the other hand, in order to improve the bonding strength, the bottom surface of the recess should be moderately rough in anticipation of an anchor effect. A surface that can be lapped, such as the back surface of the suction part, tends to form a moderately rough and flat surface. However, the bottom surface of the concave portion tends to have a small surface roughness due to flattening processing (for example, grinding processing). Roughening (for example, blasting) after flattening tends to increase flatness.

JP 2012-140257 A

An object of the present disclosure is to provide a ceramic bonded body that reduces bonding failure between the back surface of the bonding layer and the recess, firmly bonds the back surface of the bonding layer and the recess, and has excellent thermal conductivity.

A ceramic joined body according to the present disclosure includes a first ceramic member having a flat surface and a back surface located on the opposite side of the surface, a second ceramic member having a recess for accommodating the first ceramic member, and the first ceramic member. A vitreous bonding layer bonding the back surface and the bottom surface of the recess of the second ceramic member. The bottom surface of the concave portion of the second ceramic member includes a groove portion and a flat portion other than the groove portion. The arithmetic mean roughness of the groove surface is greater than the arithmetic mean roughness of the flat part surface. The joining layer joins at least the groove and the back surface.

A method for manufacturing a ceramic bonded body according to the present disclosure includes steps of preparing a first ceramic member having a flat surface and a back surface located opposite the surface; and a second ceramic member having a recess for accommodating the first ceramic member. flattening the bottom surface of the recess of the second ceramic member; forming a groove in the bottom surface of the recess of the second ceramic member by laser processing; (2) applying a glass paste to at least one of the concave portions of the ceramic member;

According to the ceramic bonded body according to the present disclosure, the bottom surface of the concave portion of the second ceramic member includes the groove portion and the flat portion other than the groove portion, and the arithmetic mean roughness of the surface of the groove portion is higher than the arithmetic mean roughness of the surface of the flat portion. big. Therefore, the ceramic bonded body according to the present disclosure reduces bonding failure between the back surface of the bonding layer and the recess, firmly bonds the back surface of the bonding layer and the recess, and has excellent thermal conductivity.

Furthermore, according to the method for manufacturing a ceramic bonded body according to the present disclosure, the bonding failure between the back surface of the bonding layer and the recess is reduced, the back surface of the bonding layer and the recess are firmly bonded, and the ceramic having excellent thermal conductivity A conjugate can be provided.

(A) is a perspective view showing a ceramic joined body according to an embodiment of the present disclosure, and (B) is a perspective view showing a second ceramic member included in the ceramic joined body shown in (A). (A) is a cross-sectional view showing a cross section taken along line XX shown in FIG. 1(A), and (B) is an enlarged view of a region Y shown in (A). 4 is an electron micrograph showing grooves formed in the bottom surface of the recess of the second ceramic member in the ceramic joined body according to the embodiment of the present disclosure. (A) is a graph showing the cross-sectional shape, width and depth of the groove when cut in the direction of arrow A shown in FIG. 3, and (B) is a graph showing the groove when cut in the direction of arrow B shown in FIG. It is a graph which shows the undulation of the bottom face.

As described above, the ceramic bonded body according to the present disclosure includes a first ceramic member having a flat surface and a back surface located on the opposite side of the flat surface, and a second ceramic member having a recess for accommodating the first ceramic member. and a vitreous bonding layer that bonds the back surface of the first ceramic member and the bottom surface of the recess of the second ceramic member. A ceramic joined body according to the present disclosure will be described based on FIGS. 1 and 2. FIG.

A ceramic bonded body 1 according to an embodiment of the present disclosure is a vacuum chuck, and as shown in FIGS. The back surface 11 b of the first ceramic member 11 and the bottom surface of the recess 12 a of the second ceramic member 12 are joined with the joining layer 13 . FIG. 1(A) is a perspective view showing a ceramic joined body 1 according to one embodiment. FIG. 2A is a cross-sectional view taken along line XX shown in FIG. 1A.

The first ceramic member 11 is not limited as long as it is made of ceramic. The first ceramic member 11 is made of, for example, a porous ceramic in which ceramic particles are connected with a binder such as glass. Examples of the ceramic forming the first ceramic member 11 include carbides such as silicon carbide, nitrides such as silicon nitride, boron nitride, and aluminum nitride, and oxides such as aluminum oxide. In the present disclosure, porous means a state in which the area ratio of closed pores in the cross section of the ceramic member is greater than 10%.

The shape and size of the first ceramic member 11 are not limited, and are appropriately set according to the application of the ceramic bonded body 1 to be obtained and the shape of the object to be adsorbed. The first ceramic member 11 has a circular shape in plan view as shown in FIG. 1(A). However, the shape of the first ceramic member 11 is not limited to a circular shape, and may have, for example, an elliptical shape or a polygonal shape (triangular, quadrangular, pentagonal, hexagonal, etc.). In the case of a polygonal shape, it may be a regular polygon or a scalene polygon.

The size of the first ceramic member 11 is not limited, and for example, the diameter may be 10 mm or more and 500 mm or less. When the first ceramic member 11 has an elliptical shape, both the major axis and the minor axis should be within such ranges. When the first ceramic member 11 is polygonal, the length of one side is, for example, 10 mm or more and 500 mm or less. The thickness of the first ceramic member 11 is, for example, 1 mm or more and 50 mm or less.

The first ceramic member 11 has a flat surface 11a and a back surface 11b opposite the surface 11a. When the first ceramic member 11 is a vacuum chuck as shown in FIG. 1, the surface 11a serves as an attraction surface for attracting an object to be attracted such as a substrate. On the other hand, the rear surface 11b faces the recess 12a when the first ceramic member 11 is accommodated in the recess 12a of the second ceramic member 12, which will be described later.

The second ceramic member 12 is a member for housing the first ceramic member 11 . The second ceramic member 12 is not limited as long as it is made of ceramic. The second ceramic member 12 is made of dense ceramic, for example. Dense ceramics are superior to porous ceramics in mechanical strength, thermal conductivity, airtightness, and the like, and are suitable for the base, which is the main component of the vacuum chuck 1 . Examples of the ceramic forming the second ceramic member 12 include carbides such as silicon carbide, nitrides such as silicon nitride, boron nitride, and aluminum nitride. The ceramic forming the second ceramic member 12 may be the same as or different from the ceramic forming the first ceramic member 11 . In the present disclosure, the term "dense" refers to a state in which the area ratio of closed pores in the cross section of the ceramic member is less than 10%.

The shape and size of the second ceramic member 12 are not limited, and are appropriately set according to the application of the ceramic bonded body 1 to be obtained and the shape of the first ceramic member 11 . The second ceramic member 12 has a circular shape in plan view as shown in FIG. 1(A). However, the shape of the second ceramic member 12 is not limited to a circular shape, and may have, for example, an elliptical shape or a polygonal shape (triangular, quadrangular, pentagonal, hexagonal, etc.). In the case of a polygonal shape, it may be a regular polygon or a scalene polygon.

The second ceramic member 12 is formed with a recess 12a for housing the first ceramic member 11 therein. The recess 12 a is formed according to the shape and size of the first ceramic member 11 . The bottom surface of the recess 12a, that is, the surface facing the back surface 11b of the first ceramic member 11 includes a groove 12b and a flat portion 12c other than the groove 12b, as shown in FIG. 1(B). FIG. 1(B) is a perspective view showing the second ceramic member 12 included in the ceramic joined body 1 shown in FIG. 1(A). When the ceramic bonded body is a vacuum chuck like the ceramic bonded body 1, a suction groove 14 is provided in the bottom surface of the concave portion 12a of the second ceramic member 12 so that the suction groove 14 and the lower surface of the second ceramic member 12 are separated. A connecting suction hole (not shown) is provided. The suction grooves 14 and the suction holes serve as paths for sucking air, and suck and hold the object to be attracted through the first ceramic member 11 .

The groove 12b is formed linearly as shown in FIG. 1(B). However, the groove portion 12b is not limited to a linear shape, and may be formed in a curved shape such as a spiral shape or a meandering shape. In the case of straight lines, the grooves 12b may intersect or be formed parallel to one direction, as shown in FIG. 1(B). The pitch of the grooves 12b (the width between the grooves 12b) is appropriately set according to the size of the bottom surface of the recesses 12a, and may be, for example, 100 μm or more and 5000 μm or less.

The width and depth of groove 12b are not limited. The groove portion 12b may have a width of, for example, 100 μm or less, or may have a width of 30 μm or more and 50 μm or less. Furthermore, the groove portion 12b may have a depth of, for example, 50 μm or less, or may have a depth of 5 μm or more and 15 μm or less.

The width of the groove 12b is longer than the depth, and the inclination of the surface of the groove 12b is preferably gentle. The shallower and smoother the groove portion 12b, the less likely a gap with the bonding layer 13 will occur, and the less likely a bonding failure will occur. The surface of the groove 12b is inclined such that, for example, when the surface of the groove 12b is plotted at intervals of 5 μm in the width direction, the angle between a straight line connecting two adjacent points and a plane horizontal in the width direction is 45° or less. Good to have.

The groove 12b may have undulations at the bottom in the extending direction of the groove 12b. When such undulations exist, a stronger anchor effect is exhibited, and the bonding strength is further improved. The height of the undulation is not limited, and for example, the maximum height of the undulation curve (difference between the bottom and the top) is 1 μm or more and 6 μm or less. Further, the undulations should preferably exist with a period smaller than the width of the groove 12b.

The arithmetic average roughness of the surface of the groove portion 12b (the inner peripheral surface and the bottom surface of the groove portion 12b) is larger than the arithmetic average roughness of the surface of the flat portion 12c. That is, the surface of the groove portion 12b is rough, and the surface of the flat portion 12c is smoother than the surface of the groove portion 12b.

Thus, when the arithmetic mean roughness of the surface of the groove portion 12b is larger than the arithmetic mean roughness of the surface of the flat portion 12c, the bonding strength of the bonding layer 13, which will be described later, is improved. Specifically, if the surface of the groove 12b is rough, the bonding layer 13 that has flowed into the groove 12b is strongly bonded by the anchor effect. On the other hand, when the surface of the flat portion 12c is smoother than the surface of the groove portion 12b, a gap is less likely to occur between the flat portion 12c and the back surface of the bonding layer 13. FIG. As a result, it becomes difficult to create a space for poor bonding. Furthermore, the thickness of the bonding layer 13 located in the flat portion 12c is thinner than the thickness of the bonding layer 13 flowing into the groove portion 12b. As a result, the thin bonding layer 13 positioned on the flat portion 12c improves thermal conductivity.

The arithmetic mean roughness of the surface of the groove portion 12b is, for example, 0.4 μm or more, and may be 0.8 μm or more. When the surface of the groove portion 12b has such arithmetic mean roughness, a stronger anchor effect is exhibited. The upper limit of the arithmetic mean roughness of the surface of the groove portion 12b is, for example, about 3 μm.

The arithmetic mean roughness of the surface of the flat portion 12c is, for example, 0.8 μm or less, and may be 0.4 μm or less. When the surface of the flat portion 12c has such an arithmetic mean roughness, the flatness of the flat portion 12c can be reduced, and the gap between the flat portion 12c and the back surface of the bonding layer 13 is less likely to occur. As a result, it becomes more difficult for a space for poor bonding to occur.

When the second ceramic member 12 is made of carbide or nitride, the surface of the groove 12b on the bottom surface of the recess 12a preferably has a lower ratio of at least one of carbon and nitrogen than the surface of the flat portion 12c. When carbides and nitrides are heated and bonded in an oxidizing atmosphere such as the air, degassing may occur due to the oxidation reaction and bubbles may be generated in the bonding layer 13 . Air bubbles can cause a decrease in bonding strength. If the ratio of carbon and nitrogen in the bottom surface of the concave portion 12a is small, the occurrence of outgassing during bonding is suppressed, the number of air bubbles is reduced, and the bonding strength is improved. If the ratio of at least one of carbon and nitrogen is low on the surface of groove 12b, active dangling bonds increase. As a result, it becomes easier to bond with oxygen contained in the bonding layer 13, which will be described later, and the bonding strength can be further improved.

The first ceramic member 11 and the second ceramic member 12 are joined via the joining layer 13 at the back surface 11b of the first ceramic member 11 and the bottom surface of the recess 12a of the second ceramic member 12 . The bonding layer 13 may at least bond the groove portion 12 b of the recess 12 a and the back surface 11 of the first ceramic member 11 . Furthermore, the bonding layer 13 may be positioned on the flat portion 12c of the recess 12a and the side surfaces of the recess 12a. When the bonding layer 13 is positioned not only on the groove portion 12b of the concave portion 12a but also on the flat portion 12c and the side surface, the bonding strength can be further improved.

The bonding layer 13 is not limited as long as it is vitreous. The thickness of the bonding layer 13 is also not limited, and the bonding layer 13 may have a thickness that allows the back surface 11b of the first ceramic member 11 and the bottom surface of the recess 12a of the second ceramic member 12 to be bonded. For example, when the bonding layer 13 exists on the flat portion 12c of the recess 12a, the thickness of the bonding layer 13 is greater than the sum of the flatness of the flat portion 12c of the recess 12a and the flatness of the back surface 11b of the first ceramic member 11. It's good. Specifically, the thickness of the bonding layer 13 is preferably about 10 μm or more and 30 μm or less.

Next, a method for manufacturing the ceramic bonded body of the present disclosure will be described. A method for manufacturing a ceramic bonded body according to the present disclosure includes the following steps (a) to (e).
(a) providing a first ceramic member having a planar surface and a back surface opposite the surface;
(b) providing a second ceramic member having a recess for accommodating the first ceramic member;
(c) flattening the bottom surface of the recess of the second ceramic member;
(d) forming a groove in the bottom surface of the recess of the second ceramic member;
(e) A step of applying a glass paste to at least one of the back surface of the first ceramic member and the concave portion of the second ceramic member, bonding and firing, and bonding at least the groove and the back surface with a vitreous bonding layer.

Step (a) is providing a first ceramic member having a flat surface and a back surface opposite the surface. The material, shape and size of the first ceramic member 11 are as described above, and detailed description thereof is omitted.

Step (b) is a step of preparing a second ceramic member having a recess for accommodating the first ceramic member. The material, shape and size of the second ceramic member 12 are as described above, and detailed description thereof will be omitted.

Step (c) is a step of flattening the bottom surface of the recess of the second ceramic member. A method for flattening the bottom surface of the recess 12a of the second ceramic member 12 is not limited. For example, the bottom surface of the concave portion 12a of the second ceramic member 12 is flattened by polishing or grinding using a whetstone or the like.

Step (d) is a step of forming a groove on the bottom surface of the recess of the second ceramic member. A region other than the groove portion 12b on the bottom surface of the concave portion 12a becomes a flat portion 12c. When the groove portion 12b is formed on the bottom surface of the concave portion 12a of the second ceramic member 12 by laser processing, the surface roughness (arithmetic mean roughness) becomes larger than that of the flat portion 12c, and undulations are formed on the bottom surface of the groove portion 12b. easier to be When undulations are formed on the bottom surface of the groove portion 12b, a stronger anchor effect is exhibited, and the ceramic bonded body 1 with improved bonding strength can be obtained. The height of the undulation is not limited, and for example, the maximum height of the undulation curve is 1 μm or more and 6 μm or less. Further, the undulations should preferably exist with a period smaller than the width of the groove 12b. Surface roughness and waviness can be adjusted by laser spot diameter, scanning pitch, irradiation intensity, and the like. The formation of the grooves 12b is not limited to laser processing, but is performed using various processing methods such as electron beam processing, dry etching processing, and blast processing so that the surface roughness of the grooves 12b is greater than that of the flat portions 12c. You may

Furthermore, if the second ceramic member 12 is made of a carbide or a nitride as described above, when the groove 12b is formed by laser processing in an oxidizing atmosphere such as air, the carbon and the Nitrogen is oxidized and vaporized. Therefore, the ratio of at least one of carbon and nitrogen is reduced on the surface of the groove portion 12b. If the ratio of at least one of carbon and nitrogen on the surface of the groove portion 12b is small, bubbles in the bonding layer 13 due to degassing from the ceramic are reduced when the bonding layer 13 is formed by heating in an oxidizing atmosphere. As a result, the bonding strength can be further improved as described above.

The groove portion 12b may be formed linearly as described above, or may be formed in a curved shape such as a spiral shape or a meandering shape. Furthermore, the groove portion 12b may be processed so that the surface has an arithmetic mean roughness of 0.4 μm or more, and may be processed so as to have an arithmetic mean roughness of 0.8 μm or more. When the surface of the groove portion 12b is processed to have such an arithmetic mean roughness, a ceramic joined body 1 exhibiting a stronger anchor effect can be obtained. The upper limit of the arithmetic mean roughness of the surface of the groove portion 12b is about 3 μm as described above.

As described above, the width of the groove 12b is longer than the depth, and the slope of the surface of the groove 12b is preferably gentle. The shallower and smoother the groove 12b, the less likely it is that poor bonding will occur. For example, when the surface of the groove portion 12b is plotted at intervals of 5 μm in the width direction, the groove portion 12b has an inclination such that the angle formed by a straight line connecting two adjacent points and a plane horizontal in the width direction is 45° or less. should be formed as follows:

On the bottom surface of the concave portion 12a of the second ceramic member 12, the portion other than the groove portion 12b is a flat portion 12c. The flat portion 12c is processed so that the surface has an arithmetic mean roughness of 0.8 μm or less, and may be processed so as to have an arithmetic mean roughness of 0.4 μm or less. When the surface of the flat portion 12c is processed to have such an arithmetic mean roughness, the ceramic joined body 1 in which the gap between the flat portion 12c and the back surface of the joining layer 13 is less likely to occur can be obtained. As a result, it is possible to obtain a ceramic bonded body 1 in which a space for defective bonding is less likely to occur. In order to make the surface of the flat portion 12c to have an arithmetic mean roughness of 0.8 μm or less, the bottom surface of the recess 12a is flattened in step (c) so as to have an arithmetic mean roughness of 0.8 μm or less. do it.

As shown in FIG. 1, when the ceramic bonded body 1 is used as a vacuum chuck, in any one of steps (b) to (d), a suction groove 14 is formed in the bottom surface of the recess 12a of the second ceramic member 12. . The suction groove 14 is formed by cutting or grinding, for example. Further, a suction hole (not shown) connecting the suction groove 14 and the lower surface of the second ceramic member 12 is formed by drilling or the like.

In step (e), glass paste is applied to at least one of the back surface of the first ceramic member and the concave portion of the second ceramic member, and the ceramic members are bonded together and fired to bond at least the groove and the back surface with a vitreous bonding layer 13 . It is a process.

Specifically, glass paste is applied to at least one of the back surface 11 b of the first ceramic member 11 and the concave portion 12 a of the second ceramic member 12 . After that, the bonding layer 13 is formed by firing while pressurizing the bonding surfaces at a temperature equal to or higher than the softening point of the glass and equal to or lower than the firing temperature of the ceramic member. At least the groove portion 12b of the concave portion 12a is joined. The amount of the glass paste to be applied may be appropriately set in consideration of the thickness of the bonding layer 13 formed after firing.

Thus, the ceramic joined body 1 according to the present disclosure is obtained through steps (a) to (e). The ceramic bonded body 1 according to the present disclosure thus obtained is used for, for example, vacuum chucks, gas supply members, and the like.

Next, a specific manufacturing method of the ceramic joined body 1 according to one embodiment of the present disclosure will be described. First, α-type silicon carbide powder, silicon powder and molding aid (phenol resin) were mixed to obtain a mixture. Next, the obtained mixture was put into a tumbling granulator to form granules, and then a compact was obtained by dry pressure molding.

Next, the obtained compact was degreased at 500° C. in a nitrogen atmosphere and then heat-treated at 1420° C. in a nitrogen atmosphere to obtain a porous body with a porosity of about 31% and an average pore diameter of 55 μm. rice field. This porous body corresponds to the first ceramic member 11 .

Next, the second ceramic member 12 is prepared, which is a substantially disk-shaped dense body containing silicon carbide as a main component and having a circular concave portion 12a in the center. The bottom surface of the concave portion 12a is flattened with a grindstone or the like so that the flatness is 50 μm or less and the arithmetic mean roughness is about 0.2 μm. After the flattening process, the groove portion 12b was formed by laser processing. As shown in FIG. 3, the grooves 12b are formed vertically and horizontally so as to cross each other. FIG. 3 is an electron microscope photograph showing grooves 11b formed in the bottom surface of the recess 12a of the second ceramic member 12 in the ceramic bonded body 1 according to one embodiment.

As shown in FIG. 4A, the groove portion 12b had a width of about 50 μm and a depth of about 6 to 10 μm. FIG. 4A is a graph showing the width and depth of the groove when cut in the direction of arrow A shown in FIG. Furthermore, as shown in FIG. 4B, undulations exist in the extending direction of the groove 12b at the bottom of the groove 12b. FIG. 4(B) is a graph showing undulations of the bottom surface of the groove when cut in the direction of arrow B shown in FIG. As shown in FIG. 4B, the undulations have a maximum height (difference between the bottom and top) of about 5 μm and are formed periodically. The surface arithmetic mean roughness of the flat portion 12c other than the groove portion 12b was 0.16 μm. On the other hand, the arithmetic average roughness of the surface of the groove portion 12b was 0.85 μm.

On the bottom surface of the concave portion 12a of the obtained second ceramic member 12, the element count ratio (Si/C) on the surface of the groove portion 12b and the surface of the flat portion 12c was calculated by energy dispersive X-ray analysis (EDS). The results were 12 for the surface of the groove portion 12b and 10 for the surface of the flat portion 12c. From this result, it can be seen that the surface of the groove portion 12b contains less carbon than the surface of the flat portion 12c.

Next, the obtained first ceramic member 11 and second ceramic member 12 were joined. Specifically, the glass paste is applied to the back surface 11b and the side surface of the first ceramic member 11, the area other than the suction grooves 14 on the bottom surface of the recess 12a of the second ceramic member 12, and the inner peripheral surface of the recess 12a. The first ceramic member 11 was inserted into the recess 12a of the second ceramic member 12 so that the back surface 11b of the member 11 and the bottom surface of the recess 12a of the second ceramic member 12 faced each other. After that, the bonding surfaces were fired at about 980° C. while applying pressure to form a vitreous bonding layer 13, and the back surface 11b of the first ceramic member 11 and the bottom surface of the concave portion 12a of the second ceramic member 12 were bonded. Thus, a ceramic joined body 1, which is a vacuum chuck, was obtained.

As test samples, the first ceramic member 11 and the plate-shaped second ceramic member 12 without the recess 12a were processed and joined in the same manner, and the resulting ceramic joined body was subjected to a torsional shear strength test. . Specifically, the ceramic bonded body was fixed with a vice, twisted with a torque wrench and broken, and the torque at the time of breaking was measured. Three ceramic bonded bodies 1 were prepared and tested three times. The joint interface between the first ceramic member 11 and the second ceramic member 12 was not broken, but the first ceramic member 11 was broken. Furthermore, the vitreous bonding layer 13 was not peeled off either.

As comparative samples, a ceramic joined body was ground without forming grooves 12b on the surface of a plate-shaped second ceramic member 12 without recesses 12a (corresponding to the bottom surface of recesses 12a), and the first ceramic was lapped. A ceramic bonded body bonded to the member 11 was obtained. It was manufactured under the same conditions as the ceramic bonded body 1 except that the groove portion 12b was not provided. The torsional shear strength test was performed three times in the same manner as the test samples for the ceramic bonded body with the ground surface and the ceramic bonded body with the lapped surface. All measured average shear stresses were lower than the test samples. Furthermore, all ceramic bonded bodies were fractured at the bonding interface, and the vitreous bonding layer 13 was peeled off.

1 Ceramic bonded body (vacuum chuck)
REFERENCE SIGNS LIST 11 first ceramic member 11a front surface 11b rear surface 12 second ceramic member 12a recess 12b groove 12c flat portion 13 bonding layer 14 suction groove

Claims (12)

a first ceramic member having a flat surface and a back surface opposite the surface;
a second ceramic member having a recess for accommodating the first ceramic member;
a vitreous bonding layer that bonds the back surface of the first ceramic member and the bottom surface of the recess of the second ceramic member;
including
the bottom surface of the recess of the second ceramic member includes a groove and a flat portion other than the groove;
The arithmetic mean roughness of the groove surface is greater than the arithmetic mean roughness of the flat part surface,
The bonding layer bonds at least the groove and the back surface,
ceramic joints. 2. The ceramic joined body according to claim 1, wherein said groove portion includes at least one of linear grooves and curved grooves. 3. The ceramic joined body according to claim 1, wherein said groove surface has an arithmetic mean roughness of 0.4 [mu]m or more. 4. The ceramic joined body according to claim 1, wherein said groove surface has an arithmetic mean roughness of 0.8 μm or more. 5. The ceramic joined body according to claim 1, 2 or 4, wherein said flat surface has an arithmetic mean roughness of less than 0.8 [mu]m. The ceramic joined body according to any one of claims 1 to 5, wherein the surface of said flat portion has an arithmetic mean roughness of less than 0.4 µm. The width of the groove is longer than the depth, and when the surface of the groove is plotted in the width direction at intervals of 5 μm, the angle between a straight line connecting two adjacent points and a plane horizontal in the width direction is 45. ° or less. 8. The ceramic joined body according to claim 1, wherein said groove has undulations in the extending direction of said groove at its bottom. 9. The ceramic joined body according to claim 8, wherein said undulations are present with a period smaller than the width of said groove. The ceramic joint according to any one of claims 1 to 9, wherein the second ceramic member is made of carbide or nitride, and the surface of the groove has a smaller ratio of at least one of carbon and nitrogen than the surface of the flat portion. body. The ceramic joined body according to any one of claims 1 to 10, which is a vacuum chuck. providing a first ceramic member having a planar surface and a back surface opposite the planar surface;
preparing a second ceramic member having a recess for accommodating the first ceramic member;
flattening the bottom surface of the recess of the second ceramic member;
forming a groove on the bottom surface of the recess of the second ceramic member by laser processing;
a step of applying a glass paste to at least one of the back surface of the first ceramic member and the concave portion of the second ceramic member, bonding and firing, and bonding at least the groove portion and the back surface with a vitreous bonding layer;
A method for manufacturing a ceramic bonded body, comprising:

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