JP6672244B2 - Manufacturing method of ceramic joined body - Google Patents

Description

  The technology disclosed in the present specification relates to a method for manufacturing a ceramic joined body.

  A heating device (also referred to as a “susceptor”) that heats an object (eg, a semiconductor wafer) to a predetermined processing temperature (eg, about 400 to 650 ° C.) while holding the object (eg, a semiconductor wafer) is known. The heating device is used as a part of a semiconductor manufacturing device such as a film forming device (such as a CVD film forming device or a sputtering film forming device) or an etching device (such as a plasma etching device).

  In general, the heating device has a plate-like holding body having a holding surface and a back surface substantially perpendicular to a predetermined direction (hereinafter, referred to as a “first direction”), and a columnar shape extending in the first direction. And a columnar support joined to the back surface. A resistance heating element is disposed inside the holder, and a plurality of power receiving electrodes (electrode pads) electrically connected to the resistance heating element are disposed on the back side of the holder. Further, the columnar support houses electrode terminals joined to the respective power receiving electrodes. When a voltage is applied to the resistance heating element via the electrode terminal and the power receiving electrode, the resistance heating element generates heat, and an object (for example, a semiconductor wafer) held on the holding surface of the holding body is heated to, for example, 400 to 650 ° C. Heated to a degree.

  Conventionally, the following method is known as a method for manufacturing a ceramic joined body of a holding body and a columnar support in a heating device. By integrally joining a pre-sintered holding body (plate-shaped ceramic body) and a pre-sintered columnar support (cylindrical ceramic body) by sintering via a ceramic bonding layer, A ceramic joined body is formed (see Patent Document 1).

JP 2000-114355 A

  In the conventional method for manufacturing a ceramic joined body, a firing step for forming each ceramic member (holding member, columnar support) is performed first, and then firing for joining the holder and the columnar support is performed. A process is performed. As described above, if the firing step for forming each ceramic member and the firing step for joining the holder and the columnar support are performed separately, for example, the production time of the ceramic joined body may be lengthened, There is room for improvement in manufacturing efficiency because it causes problems such as an increase in the number of manufacturing steps.

  In addition, such a subject is not limited to a heating device, and manufactures a ceramic joined body by joining a first ceramic member formed by a press molding method and a second ceramic member formed by a sheet laminating method. The method is a common problem.

  This specification discloses a technique capable of solving the above-described problem.

  The technology disclosed in this specification can be realized, for example, as the following modes.

(1) A method of manufacturing a ceramic joined body disclosed in the present specification is a method of manufacturing a ceramic joined body including a first ceramic member and a second ceramic member joined to each other, and is formed by a press molding method. A step of forming a press-formed precursor containing ceramics as a main component and before firing to become the first ceramic member, and a step of forming a second ceramic member containing the ceramics as a main component by a sheet laminating method. Forming the sheet lamination precursor, and interposing a bonding agent containing the ceramic powder between the press molding precursor and the sheet lamination precursor, thereby forming the press molding precursor and the sheet lamination. Forming a bonding precursor before firing with the precursor, and firing the bonding precursor to form the ceramic bonded body. And forming, a. In the method for producing a ceramic bonded body, a bonding agent containing a ceramic powder is interposed between the press-forming precursor and the sheet laminating precursor, so that the press-forming precursor and the sheet laminating precursor are not fired. Form a bonding precursor. Then, a ceramics joined body is formed by firing the joining precursor. Thus, firing for forming the first ceramic member, firing for forming the second ceramic member, and firing for joining the first ceramic member and the second ceramic member are performed. Since the processing is performed in a lump, the production efficiency of the ceramic joined body can be improved.

(2) In the method for manufacturing a ceramic joined body, the joining agent may include a powder of the ceramic, water, and a water-soluble epoxy resin. Before the firing step for bonding, in a state where a bonding agent is interposed between the press-forming precursor and the sheet laminating precursor, the press-forming precursor and the sheet The lamination precursor is easily separated and sometimes requires careful handling. On the other hand, according to the method for manufacturing a ceramic bonded body, the bonding agent interposed between the press molding precursor and the sheet lamination precursor contains a water-soluble epoxy resin having relatively high adhesiveness. Therefore, it is difficult to separate the press molding precursor and the sheet lamination precursor, and the handleability is high.

(3) In the method for manufacturing a ceramic joined body, the sheet laminate precursor may include an acrylic resin. In the method for manufacturing a ceramic joined body, the sheet lamination precursor contains an acrylic resin as a binder. Acrylic resin has a higher decarburization property than, for example, butyral resin. For this reason, according to the method for manufacturing a ceramic joined body, in the firing step of the joining precursor, the binder is sufficiently removed, so that peeling of the second ceramic member can be suppressed.

(4) In the method for manufacturing a ceramic joined body, the joining agent may include a water-soluble curing agent and a water-soluble dispersant. In the method for producing a ceramic joined body, the curing agent and the dispersing agent are water-soluble, so that they are uniformly mixed with the water-soluble epoxy resin contained in the joining agent, so that the press forming precursor and the sheet laminating precursor can be mixed. The bonding strength of the bonding agent can be increased.

(5) In the method of manufacturing a ceramic joined body, in the step of firing the bonding precursor, firing the press molding precursor, firing the sheet laminate precursor, and firing the bonding agent. The difference from the multiplication may be within 1%. In the method for producing a ceramic bonded body, in the step of firing the bonding precursor, the difference between the firing division of the press molding precursor, the firing division of the sheet laminate precursor, and the firing division of the bonded body is , Within 1%. Thereby, it is possible to suppress cracks and peeling from occurring in the ceramic joined body after the firing step.

  The technology disclosed in the present specification can be realized in various forms, for example, a holding device such as an electrostatic chuck, a vacuum chuck, a heating device such as a susceptor, and a semiconductor manufacturing device such as a shower head. Parts, furthermore, a ceramic joined body formed by joining a first ceramic member formed by a press molding method and a second ceramic member formed by a sheet laminating method, and a method of manufacturing them. It is possible to realize.

FIG. 1 is a perspective view schematically illustrating an external configuration of a heating device 100 according to the present embodiment. FIG. 2 is an explanatory diagram schematically illustrating an XZ cross-sectional configuration of a heating device 100 according to the present embodiment. It is a flowchart which shows the manufacturing method of the heating apparatus 100 in this embodiment. FIG. 3 is an explanatory diagram schematically illustrating a part of a manufacturing process of the heating device 100. FIG. 4 is an explanatory diagram illustrating a relationship between temperature and humidity in a manufacturing process of the heating device 100. FIG. 9 is an explanatory diagram showing performance evaluation results. It is explanatory drawing which shows transition of the weight loss (%) with respect to the temperature change of an acrylic resin and a butyral resin. It is explanatory drawing which shows the relationship between the content rate of resin contained in the slurry for green sheets, and recovery rate, and the content rate of resin and viscosity.

A. This embodiment:
A-1. Configuration of heating device 100:
FIG. 1 is a perspective view schematically illustrating an external configuration of a heating device 100 according to the present embodiment, and FIG. 2 is an explanatory diagram schematically illustrating an XZ cross-sectional configuration of the heating device 100 according to the present embodiment. Each drawing shows XYZ axes orthogonal to each other for specifying the direction. In the present specification, for convenience, the positive direction of the Z axis is referred to as an upward direction, and the negative direction of the Z axis is referred to as a downward direction. However, the heating device 100 is actually installed in a direction different from such a direction. You may.

  The heating device 100 is a device that heats an object (for example, a semiconductor wafer W) to a predetermined processing temperature (for example, about 400 to 650 ° C.) while holding it, and is also called a susceptor. The heating device 100 is used as a part of a semiconductor manufacturing device such as a film forming device (such as a CVD film forming device or a sputtering film forming device) or an etching device (such as a plasma etching device). The heating device 100 corresponds to a ceramic joined body in the claims.

  As shown in FIGS. 1 and 2, the heating device 100 includes a holder 10 and a columnar support 20.

(Holder 10)
The holding body 10 is a substantially disk-shaped member having a holding surface S1 and a back surface S2 that are substantially perpendicular to a predetermined direction (the vertical direction in the present embodiment). The holder 10 is formed of, for example, a ceramic mainly containing Al ₂ O ₃ (alumina). Here, the main component means a component having the largest content ratio (weight ratio). The diameter of the holding body 10 is, for example, about 100 mm or more and about 500 mm or less, and the thickness (length in the vertical direction) of the holding body 10 is, for example, about 3 mm or more and 10 mm or less. The holding body 10 corresponds to a second ceramic member in the claims.

  As shown in FIG. 2, a resistance heating element 50 as a heater for heating the holding body 10 is disposed inside the holding body 10. The resistance heating element 50 is formed of, for example, a conductive material such as tungsten or molybdenum. The pair of ends of the resistance heating element 50 are arranged on the peripheral side of the holder 10. Further, inside the holding body 10, a pair of peripheral side via conductors 51, a pair of conductive paths 53, and a via group 52 are provided. Each peripheral-side via conductor 51 is a linear conductor extending in the vertical direction, and is located on the peripheral side of the holder 10. The upper end of each peripheral via conductor 51 is connected to each end of the resistance heating element 50. Each conductive path 53 is a linear conductor extending in the radial direction of the holder 10, and the lower end of each peripheral side via conductor 51 is connected to the radially outer end of each conductive path 53. The via group 52 includes a plurality of (two in the present embodiment) vias 52A which are linear conductors extending in the vertical direction. The upper end of each via 52A is connected to the radially inner end of each conductive path 53. A pair of recesses 12 are formed near the center of the back surface S2 of the holder 10, and a power receiving electrode (electrode pad) 54 is arranged in each recess 12. Each power receiving electrode 54 is arranged so as to be exposed on the back surface S <b> 2 of the holder 10, and the exposed portion of the power receiving electrode 54 is covered with the joint 56. The lower end of each via 52A is connected to each power receiving electrode 54. Thereby, the resistance heating element 50 and each power receiving electrode 54 are electrically connected.

(Column support 20)
The columnar support 20 is a substantially columnar member extending in the predetermined direction (vertical direction). The columnar support 20 is made of, for example, ceramics mainly composed of alumina, similarly to the holder 10. The outer diameter of the columnar support 20 is, for example, about 30 mm or more and 90 mm or less, and the height (length in the vertical direction) of the columnar support 20 is, for example, about 100 mm or more and 300 mm or less. The columnar support 20 corresponds to a first ceramic member in the claims.

  The holder 10 and the columnar support 20 are arranged such that the back surface S2 of the holder 10 and the upper surface S3 of the columnar support 20 face each other in the vertical direction. The columnar support body 20 is bonded to the vicinity of the center of the back surface S2 of the holding body 10 via a bonding layer 30 formed of a bonding material described later.

  As shown in FIG. 2, a through-hole 22 that opens to the back surface S <b> 2 side of the holder 10 is formed in the columnar support 20. The through hole 22 is a hole having a substantially circular cross section that extends in substantially the same direction as the vertical direction and has a substantially constant inner diameter in the extending direction. A plurality of (two in the present embodiment) electrode terminals 70 are accommodated in the through holes 22. The upper end of each electrode terminal 70 is joined to the power receiving electrode 54 via a joint 56 containing a metal brazing material (for example, a gold brazing material). The joint 56 may include a substance other than the brazing material. When a voltage is applied to the resistance heating element 50 from a power supply (not shown) via each electrode terminal 70, each power receiving electrode 54, and the via group 52 (via 52 </ b> A), the resistance heating element 50 generates heat, and the holding surface of the holding body 10. An object (for example, a semiconductor wafer W) held on S1 is heated to a predetermined temperature (for example, about 400 to 650 ° C.).

A-2. Manufacturing method of heating device 100:
Next, a method for manufacturing the heating device 100 according to the present embodiment will be described. FIG. 3 is a flowchart illustrating a method of manufacturing the heating device 100 according to the present embodiment. FIG. 4 is an explanatory diagram schematically illustrating a part of the manufacturing process of the heating device 100. FIG. FIG. 4 is an explanatory diagram showing a relationship between temperature and humidity in the manufacturing process of FIG.

  First, the press forming precursor 20P and the sheet lamination precursor 10P are formed (see FIG. 4A). The press-formed precursor 20P is a press-formed body before firing that becomes the columnar support 20 in a firing step (S150) described below. The sheet laminate precursor 10P is a sheet laminate before firing, which becomes the holder 10 in a firing step (S150) described below. In general, it is difficult to form a structure having a concavo-convex shape, such as the heating device 100, collectively by using only the press molding method. On the other hand, in the sheet laminating method, it is relatively easy to form a plate-like member such as the holding body 10, but it is relatively difficult to form a rod-like body long in a predetermined direction such as the columnar support 20. It is. Therefore, in the present embodiment, a press-forming precursor 20P, which is a precursor of the rod-shaped columnar support 20, is formed by a press-forming method, and a sheet-laminating precursor 10P, which is a precursor of the flat holding member 10, is sheet-laminated. It is molded by the method. The details are described below.

(Molding process of press molding precursor 20P)
The press forming precursor 20P is formed by the press forming method (S110). First, 100 parts by weight of alumina powder (for example, AES-12, manufactured by Sumitomo Chemical Co., Ltd., having an average particle size of about 0.5 μm or less) was added with magnesium oxide (MgO, 0.05% by weight based on alumina powder) as a sintering aid. Parts). To the mixture obtained by adding magnesium oxide to the alumina powder, water as a solvent and an acrylic resin (for example, about 22.1 vol%) are further added and mixed by a ball mill to obtain a press slurry. The slurry for press is granulated by a spray drier to prepare a raw material powder. Next, the raw material powder is filled in a rubber mold in which a core corresponding to the through hole 22 is arranged, and cold isostatic pressing is performed. Thereby, a substantially columnar press-forming precursor 20P is formed. In addition, each size of the press molding precursor 20P is, for example, about 50 mm in length in the vertical direction, about 6 mm in outer diameter, and 2.4 mm in inner diameter.

(Molding process of sheet laminate precursor 10P)
The sheet lamination precursor 10P is formed by the sheet lamination method (S120). First, the same mixture of alumina powder (100 parts by weight) and magnesium oxide (0.05 parts by weight) used in the molding step (S110) of the press molding precursor 20P described above is further added with toluene (for example, About 16.7 parts by weight of alumina powder and methyl ethyl ketone (MEK, for example, about 16.7 parts by weight of alumina powder) are added. The mixture to which these solvents are added is placed in a resin pot containing 2 kg of boulders having a diameter of about 10 mm, and the mixture is dispersed and mixed for about 20 hours. Next, a resin (eg, butyral resin or acrylic resin) as a binder is added to the slurry obtained by dispersion and mixing, for example, in an amount of 39.5 vol% or more and 45.5 vol% or less, and the resin is mixed for about 30 minutes. To prepare a green sheet slurry. After defoaming the green sheet slurry for about 1 minute, the green sheet is formed into a sheet by a casting device (not shown) and then dried to produce a plurality of green sheets.

  Further, a metallized paste is prepared by adding a conductive powder such as tungsten or molybdenum to a mixture of an organic solvent such as alumina powder, an acrylic binder, and terpineol and kneading the mixture. By printing this metallized paste using, for example, a screen printing apparatus, a non-sintered conductor layer that will later become the resistance heating element 50, the power receiving electrode 54, or the like is formed on a specific green sheet. Further, the green sheet is printed in a state in which a via hole is provided in advance, thereby forming a non-sintered conductor portion to be a via group 52 (via 52A) later.

  Next, a plurality of (e.g., 14) of these green sheets are thermocompression-bonded, and the outer periphery is cut as necessary to produce a green sheet laminate. The green sheet laminate is cut by machining to produce a disk-shaped molded body. Thereby, the sheet laminate precursor 10P is formed.

(Production process of joining slurry 30P)
A joining slurry 30P is prepared (S130). The bonding slurry 30P is a bonding agent before being cured and fired to become the bonding layer 30 later. First, the same mixture obtained by adding 0.05 parts by weight of magnesium oxide to 100 parts by weight of alumina powder used in the molding step (S110) of the above-described press-forming precursor 20P, and further containing a carboxylic acid as a dispersant. A polymer modified product (for example, Floren G-700, manufactured by Kyoeisha Chemical Co., Ltd., content of about 0.5 part by weight based on alumina powder) is added, and ion-exchanged water as a solvent (for example, content of about 19 parts by weight based on alumina powder) is added. Parts), and perform dispersion mixing for about 12 hours. Next, a water-soluble epoxy resin (for example, glycerol polyglycidyl ether, EX313, manufactured by Nagase ChemteX Corporation, a water content of 99%, a content relative to alumina powder of about 7.16 parts by weight) is added to the dispersed and mixed slurry, Mix with a spoon for about 10 minutes. A chain aliphatic polyamine (for example, triethylenetetramine, a content of about 1.24 parts by weight based on alumina powder) as a curing agent is added to the slurry mixed with a spoon, and the mixture is further mixed with a spoon for about 2 minutes. Thereby, the joining slurry 30P is produced.

  In addition, the water solubility of the water-soluble epoxy resin is preferably 80% or more, and more preferably 90% or more. The water solubility is a numerical value of the ratio of dissolution when 90 parts of water is mixed with 10 parts of epoxy resin at normal temperature (room temperature: 25 ° C.). That is, when 10 parts of the epoxy resin are completely dissolved in 90 parts of water, the water solubility is 100%. When 5 parts of the epoxy resin is dissolved in 90 parts of water and the remaining 5 parts of the epoxy resin are not dissolved, the water solubility is 100%. The rate is 50%. The higher the water solubility of the water-soluble epoxy resin, the better. This is because the lower the water solubility, the more epoxy resin that remains without being dissolved in water, and as a result, there is a high possibility that voids will be formed in the bonding layer 30 after the firing step (S150) described later. The reason is considered to be as follows. That is, when the water solubility of the epoxy resin is low, the undissolved epoxy resin is present in a lump in the bonding layer 30, and this lump of the epoxy resin is burned off in a lump size in the degreasing and baking steps to form voids. Become. On the other hand, when the water solubility of the epoxy resin is high, even if the bulk epoxy resin is present in the bonding layer 30, the number of the bulk epoxy resin is small and the size of the bulk epoxy resin is small. Is small. For this reason, it is considered that the lower the water solubility of the epoxy resin, the higher the possibility that voids will occur in the bonding layer 30 after the firing step (S150) described later. The alumina powder corresponds to the ceramic powder in the claims, and the bonding slurry 30P corresponds to the bonding agent in the claims.

(Step of forming bonding precursor 100P)
Next, a bonding precursor 100P is formed (S140). The joining precursor 100P is obtained by interposing a cured joint 30PX between a press-forming precursor 20P and a sheet lamination precursor 10P. The cured joint body 30PX is obtained by curing the bonding slurry 30P by a heat curing treatment. The press-molding precursor 20P and the sheet lamination precursor 10P are adhered to each other by the joint cured body 30PX (see FIG. 4B). First, the sheet laminate precursor 10P is placed in a silicon rubber mold (not shown), a predetermined amount of the joining slurry 30P is applied to the back surface S2 side of the sheet laminate precursor 10P, and press molding is performed on the portion where the joining slurry 30P is applied. The precursor 20P is arranged. Then, the assembly of the sheet lamination precursor 10P and the press-forming precursor 20P with the bonding slurry 30P interposed is subjected to a thermosetting treatment by a thermostat and humidity chamber (not shown), whereby the bonding slurry 30P is cured. The joint cured body 30PX is formed. Thereby, the bonding precursor 100P is formed.

  In the bonding precursor 100P, the sheet lamination precursor 10P and the press molding precursor 20P are bonded to each other due to the relatively high adhesiveness of the water-soluble epoxy resin contained in the bonding slurry 30P, and are not easily separated from each other. However, the heating temperature of the thermosetting treatment for the bonding slurry 30P is lower than the firing temperature in the firing step described later. For this reason, in the joining precursor 100P, the sheet laminate precursor 10P, the press molding precursor 20P, and the cured joint 30PX are not fired.

  The curing conditions of the bonding slurry 30P are, for example, a heating temperature of 80 ° C., a relative humidity of 100% RH, a heating time of 5 hours, a temperature increasing rate and a temperature decreasing rate of 5 ° C./h. By setting the heating temperature to 80 ° C. or higher, the curing time of the bonding slurry 30P is reduced, and the manufacturing efficiency of the heating device 100 is improved. In addition, by setting the humidity to be high, it is possible to suppress the occurrence of cracks in the cured joint body 30PX due to drying shrinkage.

(Process of forming bonded sintered body 100X)
The bonded precursor 100P is degreased and fired to form a bonded sintered body 100X (S150). The bonded sintered body 100X includes the holding body 10, the columnar support 20, and the bonding layer 30 of the heating device 100, and does not include the bonding portion 56 and the electrode terminals 70. First, the bonding precursor 100P is removed from the silicone rubber mold and humidified and dried. The humidification drying conditions are, for example, as shown in FIG. 5, drying at a drying temperature of 80 ° C. and a relative humidity of 80% RH for 12 hours, and changing from a relative humidity of 80% RH to a humidity reduction rate of 5% RH / h for 4 hours. To a relative humidity of 60% RH and dried at a relative humidity of 60% RH for 12 hours, and a humidity of 60% RH to a relative humidity of 40% RH over 4 hours at a rate of 5% RH / h. Then, it is dried at a relative humidity of 40% RH for 12 hours, and finally, the temperature is lowered to around room temperature at a temperature lowering rate of 5 ° C./h for about 10 hours to take out the bonded sintered body 100X. Humidity at the time of cooling changed with success. Drying was performed at 80 ° C. for a total of 44 hours while controlling the relative humidity. By gradually lowering the humidity from a high-temperature and high-humidity environment with a drying temperature of 80 ° C. and a relative humidity of 80% RH, the occurrence of cracks in the bonded cured body 30PX or the bonding layer 30 due to drying shrinkage is suppressed. Hereinafter, the bonding precursor 100P after humidification and drying is referred to as a “bonding humidification and drying body”.

The bonded humidified and dried body is degreased, and the degreased bonded humidified and dried body is fired. Thus, a bonded sintered body 100X including the holding body 10 and the columnar support body 20 bonded to each other by the bonding layer 30 is manufactured (see FIG. 4C). The degreasing conditions are, for example, a degreasing temperature of 400 ° C., a degreasing time of 2 hours, a heating rate and a cooling rate of 2.5 ° C./h. The firing conditions are, for example, a firing temperature of 1600 ° C., a firing time of 6 hours, a temperature increasing rate and a temperature decreasing rate of 25 ° C./h.
The bonded sintered body 100X corresponds to a ceramic bonded body in the claims.

  After the formation of the bonded sintered body 100X, each of the electrode terminals 70 is inserted into each of the through holes 22 of the columnar support body 20, and the upper end of each of the electrode terminals 70 is brazed to each of the power receiving electrodes 54 using, for example, a gold brazing material. To form the joint 56 (S160). By the above manufacturing method, the heating device 100 having the above-described configuration is manufactured.

A-3. Effects of this embodiment:
As described above, in the manufacturing method of the heating device 100 of the present embodiment, the press forming is performed by interposing the joining slurry 30P containing the ceramic powder between the press forming precursor 20P and the sheet laminating precursor 10P. A bonding precursor 100P before firing of the precursor 20P and the sheet lamination precursor 10P is formed (see S140 in FIG. 3, FIG. 4B). Thereafter, the bonded precursor 100P is fired to form a bonded sintered body 100X (see S150 in FIG. 3 and FIG. 4C). As described above, according to the method of manufacturing the heating device 100 of the present embodiment, firing for forming the press forming precursor 20P, firing for forming the sheet lamination precursor 10P, and pressing the press forming precursor 20P Since the firing for bonding with the sheet laminate precursor 10P is performed at a time, the manufacturing efficiency of the bonded sintered body 100X (heating device 100) can be improved.

  In the present embodiment, the joining slurry 30P contains a water-soluble epoxy resin having relatively high adhesiveness. For this reason, in this embodiment, compared with the case where the joining slurry 30P contains, for example, a butyral resin instead of the water-soluble epoxy resin, the adhesive strength between the press forming precursor 20P and the sheet laminating precursor 10P is increased. And the press forming precursor 20P and the sheet laminating precursor 10P are difficult to separate. This suppresses the occurrence of breakage and the like of the bonding slurry 30P during transportation, humidification and drying of the bonding precursor 100P, and baking of the bonding humidification dried body. Properties (handling properties) can be improved. As a result, the manufacturing efficiency of the heating device 100 is improved.

  When at least one of the press forming precursor 20P and the sheet laminating precursor 10P contains a water-soluble acrylic resin as a binder, it is preferable that the bonding slurry 30P contains water as a solvent. In such a case, in the joining precursor 100P, at the interface between the sheet laminate precursor 10P and the joining slurry 30P or at the interface between the press molding precursor 20P and the joining slurry 30P, the sheet lamination precursor 10P or the press molding precursor 20P Dissolves in the water contained in the joining slurry 30P, the adhesive strength at each interface is improved, the handling of the joining precursor 100P before firing is improved, and the bonded sintered body after firing is dissolved. This is because the occurrence of cracks and peeling in 100X can be suppressed. Further, from the viewpoint of working environment and safety, it is preferable to use water as a solvent rather than a flammable organic solvent.

  Further, in the present embodiment, the sheet lamination precursor 10P preferably contains an acrylic resin as a binder. Acrylic resin has a higher decarburization property than, for example, butyral resin. For this reason, when the sheet lamination precursor 10P contains an acrylic resin as a binder, the binder is sufficiently removed in the firing step (S150) of the bonding precursor 100P, so that the green in the holder 10 formed by the sheet lamination method is used. Peeling between sheets can be suppressed. In a configuration in which the diameter of the sheet lamination precursor 10P is relatively large or a configuration in which the number of green sheets laminated in the sheet lamination precursor 10P is relatively large, a large amount of binder is used for molding the sheet lamination precursor 10P, In the drying process, the binder easily remains in the joined humidified and dried body, and peeling is likely to occur between the sheets constituting the holding body 10 after firing. Therefore, in such a configuration in which the binder easily remains in the joined humidified and dried body, it is particularly effective to include an acrylic resin as the binder in the sheet laminate precursor 10P.

  In the above embodiment, the curing agent and the dispersant contained in the bonding slurry 30P are preferably water-soluble. Thus, the curing agent and the dispersant are mixed substantially uniformly with the water-soluble epoxy resin contained in the joining slurry 30P, so that the joining strength of the joining slurry 30P can be increased.

Here, the firing division is a numerical value of the degree of shrinkage of the member in the firing step, and can be expressed by the following equation.
Multiplied by firing = dimension of member before firing / dimension of member after fired The larger the shrinkage by firing, the larger the value of the firing divided, and the smaller the shrinkage by firing, the smaller the value of the fired divided is "1". ". In the present embodiment, in the firing step (S150) of the bonding precursor 100P (bonding humidified and dried body), the firing of the press forming precursor 20P, the firing of the sheet lamination precursor 10P, and the firing of the bonding slurry 30P are performed. It is preferable that the difference from the quotient is within 1%. Here, the difference in the firing division among the three members 10P, 20P, and 30P is within 1%, which means that any two members arbitrarily selected from the three members are fired between the two members. The difference between the cracks means that the difference between the two is within 1% of the value of each of the firing cracks. Thereby, it is possible to suppress the occurrence of cracks and peeling in the joined sintered body 100X after the firing step.

  In this regard, in this embodiment, the press forming precursor 20P and the sheet laminating precursor 10P contain the same ceramic as a main component, and the bonding slurry 30P also contains the same ceramic powder. For this reason, the difference between the firing of the press molding precursor 20P, the firing of the sheet laminate precursor 10P, and the firing of the bonding slurry 30P is small. In other words, the difference in firing shrinkage among the three members 10P, 20P, and 30P in the above-described firing process (S150) is small. Thereby, for example, after the baking process, peeling between the holding body 10 and the bonding layer 30, peeling between the columnar support body 20 and the bonding layer 30, generation of cracks in the bonding layer 30, and the like occur. Is suppressed, and the bonding strength between the columnar support 20 and the holder 10 can be improved.

A-4. Performance evaluation:
Performance evaluation was performed on Examples 1 to 5 relating to the method of manufacturing the bonded sintered body 100X. FIG. 6 is an explanatory diagram showing performance evaluation results. Hereinafter, this performance evaluation will be described.

A-4-1. For each example:
As shown in FIG. 6, Examples 1 to 5 are basically the same manufacturing method (S110 to S150 in FIG. 3) of the heating apparatus 100 described above. However, in Examples 1 to 5, in the forming step (S120) of the sheet laminate precursor 10P, at least one of the type of the resin contained in the green sheet slurry (the sheet laminate precursor 10P) and the content of the resin was not satisfied. Different from each other.

  Specifically, in Example 1, the resin contained in the green sheet slurry was butyral resin, and the content was 41.0 vol%. In Example 2, the resin contained in the green sheet slurry was an acrylic resin. And the content is 39.5 vol%. In Example 3, the resin contained in the slurry for the green sheet is an acrylic resin, and the content is 41.5 vol%. In Example 4, the resin contained in the green sheet slurry was an acrylic resin, and the content was 43.5 vol%. In Example 5, the resin contained in the green sheet slurry was an acrylic resin, The content is 45.5 vol%.

A-4-2. About each performance evaluation method:
“Viscosity” and “recovery rate” in FIG. 6 mean the viscosity (Pa · s) and the recovery rate (%) of the green sheet slurry in Examples 1 to 5, respectively. The viscosity of the green sheet slurry was measured using a known B-type viscometer. The recovery rate of the green sheet slurry is based on the amount of the raw material for the green sheet slurry prepared in advance (such as the alumina powder described above), and the raw material is dispersed and mixed in the resin pot after the raw material is mixed. This is the ratio of the weight of the extracted green sheet slurry. The low recovery rate of the green sheet slurry means that the raw material adheres to the resin pot or cobblestone and remains in the resin pot, and there are many raw materials that are not used for forming the sheet laminate precursor 10P (holding body 10). This means that the production cost of the heating device 100 increases, which is not preferable.

  “Bake cracking” in FIG. 6 means the value of each burning crack of the sheet lamination precursor 10P, the press molding precursor 20P, and the joining slurry 30P in each of Examples 1 to 4. The value of each firing division was calculated by measuring the dimensions before and after the firing step (S150) of the bonding precursor 100P for each of the sheet laminate precursor 10P, the press-forming precursor 20P, and the bonding slurry 30P.

  “Handling property” in FIG. 6 means the handling property of the bonded precursor 100P (bonded humidified dry body) after degreasing. The bonded humidified and dried body is relatively fragile because almost no organic binder component is present. When the strength of the bonded humidified and dried body is equal to or higher than the first strength (for example, the strength that does not break if the bonded humidified and dried body is within a normal handling range when the bonded humidified and dried body is transported for baking), It was judged as "O". The strength of the bonded humidified dry body is less than the first strength and the second strength (for example, a strength that requires some care so as not to give vibration or impact when transporting the bonded humidified dry body) ) In the case of the above, it was judged as good “Δ”. When the strength of the bonded humidified and dried body was less than the second strength, it was determined to be poor “x”.

  “Delamination” in FIG. 6 means the presence or absence of delamination (lamellar peeling or cracking) in the bonding layer 30. The cross section of the bonding layer 30 of the bonded sintered body 100X was observed with a scanning electron microscope (SEM). If no peeling or crack was confirmed, it was judged as good “「 ”, and if peeling or crack was confirmed, It was judged as defective “x”.

A-4-3. About evaluation results:
As shown in FIG. 6, in Example 1, in the evaluation of the firing division, the value of the firing division of the sheet lamination precursor 10P is “1.220”, and the firing of the press molding precursor 20P and the bonding slurry 30P is performed. It is larger than the value "1.200". Specifically, in Example 1, the difference between the firing rate of the sheet laminate precursor 10P and the firing rate of the press forming precursor 20P or the bonding slurry 30P is 0.020, It is larger than the difference “0.012” corresponding to 1% of the value “1.200” divided by firing of the body 20P or the like. Here, in Example 1, if the value of the firing rate of the sheet laminate precursor 10P is reduced to approach the value of the firing rate of the press forming precursor 20P or the like, the manufacturing efficiency of the heating device 100 decreases. There is a possibility that. That is, in order to reduce the value of the firing rate of the sheet laminate precursor 10P, it is necessary to reduce the amount of butyral resin added to the sheet laminate precursor 10P. However, when the amount of butyral resin added is reduced, the flexibility of the green sheet may decrease due to the presence of a portion of the green sheet where the alumina powder or the like is not sufficiently dispersed. When the flexibility of the green sheet decreases, for example, cracks occur in the green sheet during transportation and lamination of the green sheet, cracks occur in a raw processing step such as drilling and cutting, and the handling of the green sheet is improved. This is because workability may be reduced.

  Further, in Example 1, it was determined to be good “Δ” in the evaluation of handleability. This means that even when the resin contained in the green sheet slurry is a butyral resin, the use of the above-described production method shown in FIG. 3 can suppress a decrease in handleability. However, in Example 1, in the evaluation of the delamination, it was determined to be defective “x”. In Example 1, in the observation of the SEM image of the cross section of the bonding layer 30 of the bonding sintered body 100X, relatively large pores were confirmed in the structure of the sintered body of the bonding layer 30. In Example 1, the reason why the relatively large pores exist in the bonding layer 30 is that the resin contained in the sheet lamination precursor 10P and the press-forming precursor 20P is formed by the bonding slurry in the step of forming the bonding precursor 100P (S140). It is considered that the resin was eluted in 30P and the amount of resin in the bonding slurry 30P increased, and remained in the bonding layer 30 as pores.

  As shown in FIG. 6, in Examples 2 to 4, in the evaluation of the firing division, the firing division value of the sheet laminate precursor 10 </ b> P is “1.188” and “1.190”. As compared with 1, the value is closer to the value of “1.200”, which is divided by firing of the press-forming precursor 20P and the like. Specifically, in Examples 2 to 4, the difference between the firing division of the sheet lamination precursor 10P and the firing division of the press molding precursor 20P is the firing division of the sheet lamination precursor 10P. Is less than or equal to the difference (0.012) corresponding to 1% of the value “1.200”. In Examples 2 to 4, unlike Example 1, even if the value of the firing rate of the sheet laminate precursor 10P is reduced, the handleability and workability of the green sheet are unlikely to be reduced. The reason is considered as follows. That is, since the acrylic resin has a dispersing function, the alumina powder and the like are sufficiently dispersed in the green sheet even if the amount of the acrylic resin is reduced in order to reduce the firing rate of the sheet laminate precursor 10P. This is because a decrease in flexibility of the green sheet is suppressed.

  Further, in Examples 2 to 4, all were judged to be the best “○” in the evaluation of the handling property, and were judged to be good “」 ”in the evaluation of the delamination. One of the reasons is that the acrylic resin has higher thermal decomposability than the butyral resin. FIG. 7 is an explanatory diagram showing a change in weight loss (%) with respect to a temperature change between an acrylic resin and a butyral resin. The weight loss rate is a ratio of the weight after the temperature rise to the initial weight of each resin (acrylic resin, butyral resin). Each resin was placed in the atmosphere, the weight of each resin was measured while raising the temperature, and the weight loss rate was calculated. The weight of each resin was measured using a differential thermal balance TG-DTA (TG8120, manufactured by Rigaku Corporation) while raising the temperature from room temperature to 700 ° C. at a rate of 2 ° C./min under an atmosphere with an air flow rate of 100 ml / min. Measured. As can be seen from FIG. 7, the acrylic resin has a significantly lower weight loss at a lower temperature than the butyral resin. This means that the acrylic resin has higher thermal decomposability (higher decarburization property) than the butyral resin. For this reason, in Examples 2 to 4, the binder is sufficiently removed from the sheet laminate precursor 10P in the degreasing / firing step (S150) as compared with Example 1, so that the bonding strength of the bonding layer 30 is high and the bonding layer The occurrence of delamination at 30 is suppressed.

  FIG. 8 is an explanatory diagram showing the relationship between the resin content and the recovery rate contained in the green sheet slurry and the relationship between the resin content and the viscosity. As shown in the evaluation results of Examples 2 to 4 of FIG. 6 and FIG. 8, the higher the content of the resin (acrylic resin) contained in the slurry for the green sheet, the higher the viscosity of the slurry for the green sheet, and the higher the recovery rate. It can be seen that is reduced. As described above, by increasing the content of the acrylic resin contained in the green sheet slurry, it is possible to reduce the difference in firing division between the sheet laminate precursor 10P and the sheet laminate precursor 10P or the joining slurry 30P. Can be. However, on the other hand, it can be seen that the higher the content of the acrylic resin contained in the green sheet slurry, the higher the viscosity of the green sheet slurry, the lower the recovery rate, and the higher the production cost of the heating device 100. . As a result, in Example 5, the recovery rate was significantly reduced. Therefore, the content of the acrylic resin contained in the green sheet slurry is preferably 39.5 vol% or more, and more preferably 45.0 vol% or less.

B. Modification:
The technology disclosed in the present specification is not limited to the above-described embodiment, and can be modified into various forms without departing from the gist thereof. For example, the following modifications are also possible.

  The method of manufacturing the heating device 100 in the above embodiment is merely an example, and can be variously modified. In FIG. 3, the order of the processes in steps S110 to S130 may be any order, and at least two of these three steps may be performed in parallel at the same time. The content rates of the forming materials of the members constituting the heating device 100 are merely examples, and may be different from the above-described numerical values.

  Further, the material for forming each member constituting the heating device 100 in the above embodiment is merely an example, and each member may be formed of another material. For example, in the heating device 100 in the above embodiment, the ceramics contained in the holder 10, the columnar support 20, and the bonding layer 30 are assumed to be alumina, but are assumed to be other ceramics such as AlN (aluminum nitride). Is also good. Further, in the above embodiment, an acrylic resin is exemplified as the resin used in the molding step (S110) of the press molding precursor 20P, but other types of resin such as butyral resin may be used. Further, in the above embodiment, the butyral resin or the acrylic resin is exemplified as the binder to be added to the green sheet slurry in the molding step (S120) of the sheet laminate precursor 10P, but a resin other than these may be used.

  In the above-described embodiment, the bonding slurry 30P includes a water-soluble epoxy resin having relatively high adhesiveness as an organic material. However, for example, the bonding slurry 30P may include another resin such as a butyral resin. Good. In the above embodiment, the joining slurry 30P may include a solvent other than water. In the above embodiment, a water-soluble modified carboxylic acid-containing polymer is added as a dispersant to the bonding slurry 30P, but another carboxylic acid-based dispersant containing no ammonium salt is added. Or a dispersant other than the carboxylic acid type may be added. Further, although a water-soluble linear aliphatic polyamine is added as a hardening agent to the joining slurry 30P, other water-soluble hardening agents may be used.

  Further, the configuration of the heating device 100 in the above embodiment is merely an example, and can be variously modified. For example, in the above embodiment, the outer shape of the holding body 10 and the columnar support body 20 as viewed in the Z-axis direction is substantially circular, but may be other shapes. Further, the electrode terminals accommodated in the through holes 22 formed in the columnar support body 20 are not limited to the terminals electrically connected to the resistance heating element 50, but may be, for example, a high frequency (RF) electrode for generating plasma. The terminal may be a terminal that is electrically connected or a terminal that is electrically connected to an attraction electrode for electrostatic attraction. Further, in the above-described embodiment, the power receiving electrode 54 is arranged in the concave portion 12 formed on the back surface S2 of the holding body 10, but may be arranged on the back surface S2 of the holding body 10. In short, the power receiving electrode only needs to be arranged on the second surface side of the holder.

  In the above embodiment, the via group 52 may include one via 52A, or may include three or more vias 52A.

  The present invention is not limited to a heating device, but is also applicable to a holding device such as an electrostatic chuck and a vacuum chuck, a heating device such as a susceptor, and a method of manufacturing a component for a semiconductor manufacturing device such as a shower head. In short, the present invention is applicable to a method for manufacturing a ceramic joined body formed by joining a first ceramic member formed by a press molding method and a second ceramic member formed by a sheet laminating method. .

10: Holder 10P: Sheet laminate precursor 12: Concave 20: Columnar support 20P: Press molding precursor 22: Through hole 30: Joining layer 30P: Joining slurry 30PX: Joining hardened body 50: Resistance heating element 51: Peripheral side Via conductor 52: Via group 52A: Via 53: Conductive path 54: Power receiving electrode 56: Bonding part 70: Electrode terminal 100: Heating device 100P: Bonding precursor 100X: Bonded sintered body S1: Holding surface S2: Back surface S3: Top surface

Claims (2)

A first ceramic member, a second ceramic member having a holding surface and a back surface substantially orthogonal to a predetermined direction and being a plate-like holding member for holding a semiconductor wafer, wherein the first ceramic member And a method for manufacturing a ceramic joined body in which the second ceramic member and the second ceramic member are joined to each other,
The first ceramic member has a shape extending in the predetermined direction, and is a columnar support joined to the back surface of the second ceramic member.
A step of forming a pre-fired press-forming precursor to be the first ceramic member, which comprises ceramics as a main component, by a press forming method;
Forming a sheet laminate precursor containing the ceramics as a main component and containing an acrylic resin having a content of 45.0 vol% or less and before firing to be the second ceramic member by a sheet lamination method;
By interposing a bonding agent containing the ceramic powder, water and a water-soluble epoxy resin between the press molding precursor and the sheet lamination precursor, the press molding precursor and the sheet lamination precursor are formed. Forming a bonding precursor before firing,
By firing the bonding precursor, seen including a step of forming the ceramic bonding article,
In the step of firing the bonding precursor, the difference between the firing rate of the press forming precursor, the firing rate of the sheet laminate precursor, and the firing rate of the bonding agent is within 1%. A method for manufacturing a ceramic joined body, comprising: The method for manufacturing a ceramic joined body according to claim 1,
The method for manufacturing a ceramic joined body, wherein the joining agent contains a water-soluble curing agent and a water-soluble dispersant.

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