JP6612793B2 - Composite material - Google Patents

Description

  The present disclosure relates to composite members and adhesive compositions.

  Conventionally, semiconductor manufacturing parts such as electrostatic chucks are known. The electrostatic chuck has a function of fixing the semiconductor wafer (see Patent Documents 1 and 2). The electrostatic chuck includes a ceramic substrate, a metal substrate, and an adhesive layer that bonds them. An adhesive layer containing a silicone resin is known.

JP 2014-165267 A Japanese Patent No. 4409373

  The adhesive layer provided in the electrostatic chuck may become hot during use. Silicone resins are known to thermally degrade when exposed to high temperatures for long periods of time. Among them, the curing deterioration is gradually oxidized and hardened by radicals derived from oxygen. When the silicone resin is cured and deteriorated, the adhesive layer itself is also cured and deteriorated.

  In order to suppress the curing deterioration of the silicone resin, it is considered that a substance having a radical scavenging ability is included in the adhesive layer. However, in this case, a substance having radical scavenging ability may release moisture and generate bubbles. When bubbles are generated, an unbonded portion is generated at the interface between the adhesive layer and the ceramic substrate or the metal substrate. As a result, the surface temperature of the semiconductor wafer fixed to the electrostatic chuck becomes non-uniform.

  An aspect of the present disclosure aims to provide a composite member and an adhesive composition that can suppress curing deterioration of an adhesive layer and can suppress generation of bubbles in the adhesive layer.

One aspect of the present disclosure includes: a first member having at least a surface made of ceramic; a second member having at least a surface made of metal; and the surface of the first member made of ceramic. An adhesive layer that adheres the surface of the second member made of the metal, and the adhesive layer includes a silicone resin and an oxide containing a Group 3 or Group 4 element. The amount of weight loss of the oxide in thermogravimetry is less than 2% by weight when the temperature is raised from room temperature to 500 ° C. at a heating rate of 10 ° C./min, and the BET specific surface area of the oxide Is more than 10 mm ² / g, and the adhesive layer is a composite member containing 3 parts by weight or more of the oxide with respect to 100 parts by weight of the silicone resin. The composite member that is one embodiment of the present disclosure can suppress curing deterioration of the adhesive layer, and can suppress generation of bubbles in the adhesive layer.

Another aspect of the present disclosure is an adhesive composition including a silicone resin and an oxide containing a Group 3 or Group 4 element, wherein the weight loss amount of the oxide in thermogravimetry is When the temperature is increased from room temperature to 500 ° C. at a temperature increase rate of 10 ° C./min, the BET specific surface area of the oxide exceeds 10 mm ² / g, and 100 parts by weight of the silicone resin is added. On the other hand, it is an adhesive composition containing 3 parts by weight or more of the oxide. The adhesive composition which is another aspect of this indication can be used for formation of the contact bonding layer in a composite member, for example. The formed adhesive layer is less likely to be hardened and deteriorated and is less likely to generate bubbles.

2 is a side cross-sectional view illustrating a configuration of a composite member 1. FIG.

An embodiment of the present disclosure will be described.
1. Composite Member The composite member of the present disclosure includes a first member, a second member, and an adhesive layer. At least a part of the surface of the first member is made of ceramic. For example, the first member may be entirely made of ceramic, a part thereof may be made of ceramic, and the other part may be made of another material. Examples of the first member include a ceramic substrate.

  As a ceramic, a well-known thing can be selected suitably and can be used. Examples of the ceramic material include aluminum oxide (alumina), aluminum nitride, yttrium oxide (yttria), and the like. Ceramic also includes a glass component.

  At least a part of the surface of the second member is made of metal. For example, the second member may be entirely made of metal, a part thereof may be made of metal, and the other part may be made of another material. Examples of the second member include a metal substrate. Examples of the metal include aluminum, iron, gold, silver, copper, stainless steel, and titanium. The metal may be an alloy of a plurality of elements.

  The adhesion layer is a layer that adheres the ceramic surface of the first member to the metal surface of the second member. The adhesive layer includes a silicone resin and an oxide containing a Group 3 or Group 4 element.

  Examples of the silicone resin include addition-curable silicone resins and condensation-curable silicone resins. When an addition-curable silicone resin is used, the generation of bubbles in the adhesive layer can be further suppressed.

  The addition-curable silicone resin includes at least (A) an organopolysiloxane having at least two silicon atom-bonded alkenyl groups in one molecule, and (B) at least two silicon atom-bonded hydrogen atoms in one molecule. And (C) a catalyst for hydrosilylation reaction.

  The blending amount of the component (B) is an amount sufficient to crosslink the component (A). For example, the amount of the component (B) The amount of silicon atom-bonded hydrogen atoms is preferably in an amount in the range of 0.5 to 10 mol, and particularly preferably in an amount in the range of 0.8 to 1.2 mol.

  The component (C) is a component that promotes the hydrosilylation reaction between the alkenyl group and the silicon atom-bonded hydrogen atom. The amount of component (C) is sufficient to promote the curing of the silicone resin. For example, when component (C) is a platinum catalyst, the concentration of platinum metal in the silicone resin is expressed in weight units. Therefore, the amount is preferably in the range of 0.01 to 1000 ppm, and more preferably in the range of 0.1 to 500 ppm.

  Examples of the Group 3 elements include scandium, yttrium, lanthanum, actinium, lutetium, laurenium, lanthanoid, and actinoid. Examples of Group 4 elements include titanium, zirconium, and hafnium.

  Examples of the oxide containing a Group 3 or Group 4 element include one or more selected from the group consisting of titanium oxide, cerium oxide, and barium zirconate. These oxides have an effect of capturing radicals generated from the silicone resin and suppressing curing deterioration of the silicone resin.

  The addition amount of the oxide is 3 parts by weight or more with respect to 100 parts by weight of the silicone resin. Thereby, curing deterioration of the silicone resin can be suppressed. The amount of the oxide added is preferably 5 parts by weight or more with respect to 100 parts by weight of the silicone resin. In this case, curing deterioration of the silicone resin can be further suppressed. The amount of oxide added is preferably 50 parts by weight or less with respect to 100 parts by weight of the silicone resin. In this case, it is excellent in the dispersibility of an oxide.

  The weight reduction amount of the oxide in thermogravimetry (hereinafter sometimes referred to simply as “weight reduction amount”) is less than 2 wt% when the temperature is raised from room temperature to 500 ° C. at a temperature rising rate of 10 ° C./min. . Thereby, generation | occurrence | production of the bubble in an contact bonding layer can be suppressed.

  The method of thermogravimetry is as follows. Place powder sample in aluminum pan. Next, the temperature is raised from room temperature to 600 ° C. at a temperature rising rate of 10 ° C./min in a nitrogen atmosphere. At this time, the weight change is repeatedly measured at a sample interval of 1 second. A value obtained by subtracting the weight at 500 ° C. from the weight at room temperature is defined as a weight reduction amount.

In addition, it is estimated that the weight reduction | decrease of an oxide arises because the water | moisture content adsorb | sucked to the oxide surface and the thermal decomposition component volatilize.
The BET specific surface area of the oxide exceeds 10 mm ² / g. Thereby, curing deterioration of the silicone resin can be suppressed, and generation of bubbles in the adhesive layer can be suppressed. The BET specific surface area of the oxide is preferably more than 40 mm ² / g. In this case, since the oxide having a large surface area can capture radicals, the curing deterioration of the silicone resin can be further suppressed.

The method for measuring the BET specific surface area is as follows. The powder sample is degassed at 100 ° C. for 60 minutes. Next, measurement is performed by the BET flow method (one-point method). The gas at the time of measurement is a mixed gas of He and N _2, and the volume ratio thereof is He: N ₂ = 7: 3. The average value of three measurements is taken as the BET specific surface area.

The form of the oxide can be, for example, powder or particulate.
The adhesive layer may contain other components in addition to the silicone resin and the oxide. Other components include, for example, alumina, silica (for example, wet silica, dry silica, fumed silica, etc.), zirconia, aluminum nitride, silicon nitride, silicon carbide and other ceramic powders, aluminum, silver, copper and other metals. Examples thereof include powder, barium sulfate, and calcium carbonate. These components have effects such as imparting thermal conductivity, adjusting viscosity, and reinforcing.

  It is preferable that the adhesive layer does not generate bubbles when heated at 250 ° C. for 165 hours. When bubbles do not occur, a portion that is not bonded is less likely to occur at the interface between the adhesive layer and the first member or the second member.

  When the initial rubber hardness of the adhesive layer is (a) and the rubber hardness after heating the adhesive layer at 250 ° C. for 1000 hours is (b), (b) / (a) is preferably less than 4. . When (b) / (a) is less than 4, since the adhesive layer is softer, the first member and the second member are generated due to the difference in thermal expansion coefficient between the first member and the second member. The peeling of the adhesive layer in the vicinity of the end with the member can be further suppressed.

  The method for measuring rubber hardness is as follows. The rubber hardness of the adhesive layer is measured using a JIS A TYPE rubber hardness tester. The rubber hardness is measured on the upper and lower surfaces of a cured body having an inner diameter of 18 mm and a length of 17 mm, and the average value is defined as the rubber hardness.

  A bonding surface between the first member and the bonding layer is defined as a first bonding surface. A bonding surface between the second member and the bonding layer is defined as a second bonding surface. The first adhesive surface and / or the second adhesive surface is preferably a flat surface. And when the 1st adhesion surface is a plane, it is preferred that the area of the 1st adhesion surface is more than the area of the circle of diameter 100mm. When the second adhesive surface is a flat surface, the area of the second adhesive surface is preferably equal to or greater than the area of a circle having a diameter of 100 mm. When the first adhesive surface and the second adhesive surface are flat surfaces, the areas of the first adhesive surface and the second adhesive surface are each preferably equal to or larger than the area of a circle having a diameter of 100 mm.

  When the first adhesive surface and / or the second adhesive surface is as described above, the first member generated due to the difference in thermal expansion coefficient between the first member and the second member; Peeling of the adhesive layer in the vicinity of the end with the second member can be further suppressed.

Further, when the area of the adhesive layer is equal to or larger than the area of a circle having a diameter of 100 mm, the heat conduction between the first member and the second member is further enhanced in the entire plane than when the area is less than that. It becomes uniform.
The composite member constitutes, for example, part or all of a semiconductor manufacturing component. Examples of the semiconductor manufacturing component include a shower head, an electrostatic chuck, a CVD heater, and a vacuum chuck.

  The composite member can be manufactured, for example, by the following method. An adhesive composition described later is applied to the surface of the first member, and the second member is bonded to the application surface. Moreover, an adhesive composition may be apply | coated to the surface of a 2nd member, and a 1st member may be bonded together on the application surface. Moreover, an adhesive composition may be apply | coated to the surface of a 1st member, and the surface of a 2nd member, respectively, and both application surfaces may be bonded together. In the case of these production methods, the applied adhesive composition is cured to form an adhesive layer.

  Moreover, you may manufacture a composite member with the following method, for example. An adhesive sheet having the same composition as the adhesive layer described above is created. The adhesive sheet may have fluidity or may be solid. An adhesive sheet is disposed between the first member and the second member. The first member and the second member are each pressed against the side of the adhesive sheet. In the case of this manufacturing method, the adhesive sheet forms an adhesive layer.

  For example, as shown in FIG. 1, the composite member 1 includes a first member 3, a second member 5, and an adhesive layer 7. For example, when the composite member 1 is an electrostatic chuck, the first member 3 is a ceramic substrate, and the second member 5 is a metal substrate.

2. Adhesive Composition The adhesive composition of the present disclosure has the same composition as the adhesive layer described above, and includes a silicone resin and an oxide. The oxide is an oxide containing a Group 3 or Group 4 element. The types, physical properties, addition amounts, and the like of the silicone resin and oxide are the same as those of the silicone resin and oxide in the adhesive layer described above. The adhesive composition may contain components other than the silicone resin and the oxide.

  It is preferable that the adhesive composition of the present disclosure does not generate bubbles when heated at 250 ° C. for 165 hours. When bubbles do not occur, a portion that is not bonded is less likely to occur at the interface between the adhesive layer formed using the adhesive composition and the first member or the second member.

  When the initial rubber hardness of the adhesive composition is (a) and the rubber hardness after heating the adhesive composition at 250 ° C. for 1000 hours is (b), (b) / (a) is less than 4. Preferably there is. When (b) / (a) is less than 4, the adhesive composition is softer, so that the two components produced due to the difference in thermal expansion coefficient between the two members to which the adhesive composition part adheres The peeling of the adhesive composition in the vicinity of the end can be further suppressed.

For example, the adhesive composition may have fluidity, may be in the form of a paste, or may be solid. The adhesive composition can be used, for example, for producing a composite member. When the adhesive composition is used for manufacturing a composite member, the adhesive composition forms an adhesive layer.
<Example>
(1) Production of Adhesive Composition Oxide powders A1 to A5 having the characteristics shown in Table 1 below were prepared.

A1 is TiO ₂ powder (Nippon Aerosil Co., Ltd., trade name: aeroxide P25). A2 is TiO ₂ powder (Nippon Aerosil Co., Ltd., trade name: aeroxide T805). A3 is a TiO ₂ powder (Taika Corporation, trade name: JR-405). A4 is a TiO ₂ powder (Taika Co., Ltd., trade name: MTY-100SAS). A5 is SiO ₂ powder (Nippon Aerosil Co., Ltd., trade name: RY200S). The measurement methods of “BET specific surface area” and “weight loss” in Table 1 are the methods described above.

  Adhesive compositions S1 to S14 shown in Tables 2 and 3 below were produced by mixing a raw material containing a silicone resin and any of oxide powders A1 to A5. However, for S13, no oxide powder was added.

The “addition amount” in Tables 2 and 3 is the addition amount of oxide powder (unit: parts by weight) when the weight of the silicone resin is 100 parts by weight. The adhesive compositions S1 to S14 are pasty and have fluidity that allows screen printing. Tables 2 and 3 also show the BET specific surface area and weight loss in the added oxide powder.
(2) Evaluation of adhesive composition The following evaluation was performed about each of adhesive composition S1-S14.

(2-1) Preparation of test body for evaluation of air bubbles An adhesive composition was applied to one surface of an aluminum plate, and a glass plate was bonded to the coated surface to prepare a test body. The glass plate corresponds to the first member, and the aluminum plate corresponds to the second member. The layer formed by curing the adhesive composition corresponds to the adhesive layer. The test body includes a glass plate, an aluminum plate, and an adhesive layer for bonding them. The test body corresponds to a composite member.

  The glass constituting the glass plate is float glass. The aluminum constituting the aluminum plate is A6061P-T6. The glass plate is a 110 mm square plate having a thickness of 1.1 mm. The aluminum plate is a square plate having a length of 130 mm and a thickness of 1.0 mm. The thickness of the adhesive layer is 0.3 mm. The area of the adhesive layer is larger than the area of a circle having a diameter of 100 mm.

(2-2) Evaluation of bubbles The specimen prepared in (2-1) was heated at 250 ° C. for 165 hours. After heating, whether or not bubbles were generated in the adhesive layer was visually confirmed through a glass plate. The results are shown in Tables 2 and 3 above. In Tables 2 and 3, “◯” indicates that bubbles are not generated, and “×” indicates that many bubbles are generated.

  No bubbles were generated in the adhesive compositions S1 and S2. The reason is presumed to be that a sufficient amount of titanium oxide having a small weight loss and a large BET specific surface area is added. On the other hand, bubbles were generated in the adhesive compositions S3 to S12.

  The reason is presumed to be because the amount of titanium oxide added is small for the adhesive composition S3. Moreover, about adhesive composition S4 and S10, it is estimated that it is because the weight reduction amount of a titanium oxide is large and there is little addition amount of a titanium oxide. Moreover, about adhesive composition S5, S6, S11, S12, it is estimated that it is because the weight reduction amount of a titanium oxide is large. Moreover, about adhesive composition S7, it is estimated that it is because the BET specific surface area of a titanium oxide is small and there is little addition amount of a titanium oxide. Moreover, about adhesive composition S8 and S9, it is estimated that it is because the BET specific surface area of a titanium oxide is small.

(2-3) Measurement of rubber hardness The rubber hardness of the adhesive composition was measured using a rubber hardness meter of JIS A TYPE. The method for measuring rubber hardness is the method described above. Rubber hardness is an index representing the degree of curing deterioration. The rubber hardness was measured immediately after production of the adhesive composition and after heating at 250 ° C. for 1000 hours. The measurement results are shown in Tables 2 and 3 above.

  In Tables 2 and 3, “Initial (a)” represents the rubber hardness immediately after production of the adhesive composition. In Tables 2 and 3, “after 1000 h (b)” represents the rubber hardness of the adhesive composition after heating at 250 ° C. for 1000 hours. “(B) / (a)” in Tables 2 and 3 represents a ratio of the value of “after 1000 h (b)” to the value of “initial (a)”. The larger the value of “(b) / (a)”, the harder it is due to heating, which means that it is more likely to be hardened and deteriorated.

  In the adhesive compositions S1 and S2, the values of “(b) / (a)” were both small. The reason is presumed to be that a sufficient amount of titanium oxide having a small weight loss and a large BET specific surface area is added. On the other hand, in the adhesive compositions S3 to S5, S7 to S10, S13, and S14, the value of “(b) / (a)” was large.

The reason is presumed that the adhesive compositions S3 and S10 have a small amount of titanium oxide added. Moreover, about adhesive composition S4, it is estimated that it is because there is little addition amount of a titanium oxide and the weight reduction amount of a titanium oxide is large. Moreover, about adhesive composition S5, it is estimated that it is because the weight reduction amount of a titanium oxide is large. Moreover, about adhesive composition S7, it is estimated that it is because the BET specific surface area of a titanium oxide is small and there is little addition amount of a titanium oxide. Moreover, about adhesive composition S8 and S9, it is estimated that it is because the BET specific surface area of a titanium oxide is small. Moreover, about adhesive composition S13, it is estimated that it is because the oxide is not added. Also, the adhesive composition S14, the type of oxide is presumed to be because a SiO _2.
<Other embodiments>
As mentioned above, although embodiment of this indication was described, this indication is not limited to the above-mentioned embodiment, and can carry out various modifications.

  (1) A plurality of functions of one constituent element in the embodiment may be realized by a plurality of constituent elements, or a single function of one constituent element may be realized by a plurality of constituent elements. . Further, a plurality of functions possessed by a plurality of constituent elements may be realized by one constituent element, or one function realized by a plurality of constituent elements may be realized by one constituent element. Moreover, you may abbreviate | omit a part of structure of the said embodiment. Further, at least a part of the configuration of the embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified from the wording described in the claims are embodiments of the present disclosure.

  (2) In addition to the composite member and the adhesive composition described above, the present disclosure may be realized in various forms such as a system including the composite member as a constituent element, a method for manufacturing the adhesive composition, and a method for manufacturing the composite member. it can.

DESCRIPTION OF SYMBOLS 1 ... Composite member, 3 ... 1st member, 5 ... 2nd member, 7 ... Adhesive layer

Claims (6)

A first member having at least a portion of a surface made of ceramic;
A second member having at least a part of a surface made of metal;
An adhesive layer for adhering the surface of the first member made of ceramic and the surface of the second member made of metal;
A composite member comprising:
The adhesive layer includes a resin composed only of a silicone resin, and an oxide containing a Group 3 or Group 4 element,
The oxide is one or more selected from the group consisting of titanium oxide, cerium oxide, and barium zirconate,
The weight reduction rate of the oxide in thermogravimetry is less than 2% by weight when the temperature is increased from room temperature to 500 ° C. at a temperature increase rate of 10 ° C./min.
The oxide has a BET specific surface area of greater than 10 m ² / g;
The adhesive layer, 100 parts by weight of said silicone resin, saw including three or more parts by weight of the oxide,
A composite member constituting part or all of a shower head, electrostatic chuck, CVD heater, or vacuum chuck . The composite member according to claim 1,
The oxide has a BET specific surface area of more than 40 m ² / g. The composite member according to claim 1 or 2,
The adhesive layer is a composite member including 5 parts by weight or more of the oxide with respect to 100 parts by weight of the silicone resin. The composite member according to any one of claims 1 to 3,
A composite member in which the silicone resin is an addition-curable silicone resin. The composite member according to any one of claims 1 to 4 ,
The adhesive layer does not generate bubbles when heated at 250 ° C. for 165 hours,
A composite in which (b) / (a) is less than 4 where (a) is the initial rubber hardness of the adhesive layer and (b) is the rubber hardness after the adhesive layer is heated at 250 ° C. for 1000 hours. Element. It is a composite member given in any 1 paragraph of Claims 1-5 ,
The composite member having an area of the adhesive layer equal to or larger than a circle having a diameter of 100 mm.

Images