Method for manufacturing substrate laminate

Abstract

To provide a method for manufacturing a substrate laminate having high bonding strength while using a resin material for an insulator layer.SOLUTION: A method for manufacturing a substrate laminate includes the steps of: forming an organic insulator layer by deposing and hardening a curable resin composition on a first substrate 1; activating the joint surface of the organic insulator layer; bringing the activated joint surface of the organic insulator layer into contact with a basic aqueous solution or pure water; and joining the joint surface of the organic insulator layer of the first substrate to a second substrate 2. The curable resin composition contains a thermoset cure resin, and a compound having an alkylsilyl group or an alkoxysilyl group in molecules.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a substrate laminate. [Background technology]

[0002] As semiconductor devices become more sophisticated, they are increasingly being made three-dimensional by stacking multiple semiconductor chips. In such substrate stacks where multiple semiconductor chips are stacked, electrodes on the substrates have traditionally been joined via solder, but in recent years hybrid bonding has been considered as a method for joining electrodes.

[0003] Figure 1 shows a schematic diagram illustrating the manufacturing process of a substrate laminate using hybrid bonding. In hybrid bonding, first, an electrode 3 and an insulating layer 4 are formed on one side of a first substrate 1 and a second substrate 2. Next, the surfaces on which the electrode 3 and insulating layer 4 are formed are polished and flattened, and then the electrodes 3 and insulating layers 4 of the first substrate 1 and the second substrate 2 are simultaneously bonded by high-temperature treatment to obtain a substrate laminate. A substrate laminate produced by hybrid bonding has excellent properties, such as shorter wiring distances and improved electrical properties and packaging density, because it does not use solder.

[0004] In hybrid bonding, inorganic insulating layers made of inorganic materials such as SiO2 have been considered for the insulating layer. However, inorganic insulating layers have the problem of prone to bonding failure when foreign matter or voids are trapped between the substrates. Therefore, the use of resin materials such as thermosetting resins for the insulating layer has been proposed. By using a resin material for the insulating layer, even if foreign matter or voids are trapped, they can be embedded in the insulating layer, preventing bonding failure. Furthermore, insulating layers made of resin materials (organic insulating layers) are flexible, so gaps are less likely to form at the joint than when bonding inorganic insulating layers together, which reduces moisture penetration and improves durability.

[0005] On the other hand, the substrate laminate using the organic insulating layer as described above has a problem of insufficient bonding strength. Therefore, in order to improve the bonding strength of the organic insulating layer, Patent Document 1 discloses a method for manufacturing a substrate laminate having a bonding layer with silanol groups. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2020 / 085183 Summary of the Invention [Problem to be solved by the invention]

[0007] However, although the organic insulating layer having silanol groups as disclosed in Patent Document 1 has been shown to have a certain degree of effect in improving bonding strength, it has not been possible to obtain the expected bonding strength, and further improvement in bonding strength is required.

[0008] An object of the present invention is to provide a method for manufacturing a substrate laminate that has high bonding strength even when a resin material is used for the insulating layer. [Means for solving the problem]

[0009] The present invention is comprised of the following Disclosures 1 to 10. The present invention will be described in detail below. [Disclosure 1] forming an organic insulating layer by depositing and curing a curable resin composition on a first substrate; activating the bonding surface of the organic insulating layer; a step of contacting a basic aqueous solution or pure water with the activated bonding surface of the organic insulating layer; bonding a bonding surface of the organic insulating layer of the first substrate to a second substrate, The curable resin composition comprises a thermosetting resin and a compound having an alkylsilyl group or an alkoxysilyl group in the molecule. [Disclosure 2] The content of silanol groups in the curable resin composition is 10 -3 mol / g or less. [Disclosure 3] The method for producing a substrate laminate according to Aspect 1 or 2, wherein the compound has a structure represented by formula (1). [ka] where R 1 and R 2 each independently represents a hydrogen atom or an arbitrary substituent, and n represents an integer of 0 or more and 100 or less. [Disclosure 4] The method for producing a substrate laminate according to Aspect 1 or 2, wherein the compound has a structure represented by formula (2): [ka] where R 3 represents a hydrogen atom or an arbitrary substituent, j represents an integer of 1 or more and 40 or less, and k represents an integer of 1 or more and 40 or less. [Disclosure 5] 3. The method for producing a substrate laminate according to claim 1 or 2, wherein the compound is a cage silsesquioxane having 12 or less Si atoms in the cyclic structure. [Disclosure 6] The method for producing a substrate laminate according to any one of Disclosures 1 to 5, wherein the curable resin composition contains at least one selected from the group consisting of a phenoxy resin, a polyimide resin, a polyimide precursor, a polyamide resin, a bismaleimide, and an epoxy resin. [Disclosure 7] The method for producing a substrate laminate according to any one of Disclosures 1 to 6, wherein the storage modulus of the organic insulating layer at 25° C. is 2.0 GPa or more. [Disclosure 8] The method for producing a substrate laminate according to any one of Disclosures 1 to 7, further comprising the step of forming an electrode on the first substrate before the step of forming the organic insulating layer. [Disclosure 9] A method for manufacturing a substrate laminate according to Disclosure 8, comprising, before the step of bonding the first substrate and the second substrate, a step of forming an electrode on the second substrate and a step of forming an insulating layer on the electrode surface of the second substrate. [Disclosure 10] The method for producing a substrate laminate according to Disclosure 9, further comprising polishing a bonding surface of at least one of the organic insulating layer and the insulating layer.

[0010] The method for producing a substrate laminate of the present invention first involves a step of forming an organic insulating layer by forming a film of a curable resin composition on a first substrate and curing the film. By using an organic insulating layer as the insulating layer of a substrate, even if foreign matter or voids are trapped during bonding of the substrates, these can be filled in, thereby preventing poor bonding of the substrates. Furthermore, even if warping occurs in the substrate, stress can be alleviated to eliminate the warping. Furthermore, because the organic insulating layer is flexible, gaps are less likely to form at the bonded portion than when inorganic insulating layers are bonded together, which can prevent moisture penetration and improve durability. The organic insulating layer is not particularly limited as long as it is made of an organic material, but is preferably a cured product of a curable resin composition because of its ease of production, and the curable resin composition preferably contains a thermosetting resin.

[0011] The thermosetting resin may be a resin containing a polymerizable compound and, if necessary, a curing agent. Since high-temperature treatment is performed during substrate bonding, the polymerizable compound preferably has excellent heat resistance when cured. Examples of such polymerizable compounds include phenoxy resin, polyimide resin, polyimide precursor, polyamide resin, maleimide resin, epoxy resin, and silicone resin. Among these, the thermosetting resin preferably contains at least one selected from the group consisting of phenoxy resin, polyimide resin, polyimide precursor, polyamide resin, maleimide resin, and epoxy resin, due to its excellent adhesive strength. Epoxy resin or maleimide resin is more preferred, and maleimide resin is even more preferred due to its particularly excellent moisture resistance.

[0012] Examples of the epoxy resin include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, phenol novolac type epoxy resins, biphenyl type epoxy resins, biphenyl novolac type epoxy resins, biphenol type epoxy resins, naphthalene type epoxy resins, fluorene type epoxy resins, phenol aralkyl type epoxy resins, biphenyl aralkyl type epoxy resins, naphthol aralkyl type epoxy resins, dicyclopentadiene type epoxy resins, anthracene type epoxy resins, epoxy resins having an adamantane skeleton, epoxy resins having a tricyclodecane skeleton, and epoxy resins having a triazine nucleus in the skeleton.

[0013] The maleimide resin is preferably a bifunctional or higher functional maleimide resin, since this facilitates increasing the elastic modulus after curing. Examples of bifunctional or higher functional maleimide resins include bismaleimide and trifunctional or higher functional maleimide compounds. Examples of bismaleimide include bis(3-ethyl-5-methyl-4-maleimidophenyl)methane, 1,4-bis(maleimido)butane, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, 1,2-bis(maleimido)ethane, N,N'-1,4-phenylenedimaleimide, N,N'-1,3-phenylenedimaleimide, and 4,4'-bismaleimidodiphenylmethane. Examples of trifunctional or higher functional maleimide compounds include biphenylaralkyl maleimide compounds.

[0014] The content of the polymerizable compound, or the total content of the polymerizable compound and the curing agent when the curing agent is contained, is preferably 20% by weight or more, more preferably 30% by weight or more, and preferably 90% by weight or less, and more preferably 80% by weight or less, based on 100% by weight of the curable resin composition. By ensuring that the content of the polymerizable compound is within the above range, even if foreign matter or voids are trapped during bonding of substrates, these can be filled to prevent poor bonding of the substrates. In this specification, "100% by weight of the curable resin composition" refers to 100% by weight of the components (solids) of the curable resin composition excluding the solvent.

[0015] Examples of the curing agent include active ester compounds, acid anhydride compounds, phenol compounds, and amine compounds when the polymerizable compound is an epoxy resin; and examples of the curing agent include vinyl compounds, styryl compounds, allyl compounds, and (meth)acrylic compounds when the polymerizable compound is a maleimide resin.

[0016] The curable resin composition may contain a curing accelerator. The use of the curing accelerator can shorten the curing time of the thermosetting resin. Examples of the curing accelerator include imidazole-based curing accelerators, tertiary amine-based curing accelerators, phosphine-based curing accelerators, photobase generators, sulfonium salt-based curing accelerators, organic peroxide initiators, and azo compound initiators.

[0017] From the viewpoint of further promoting curing, the content of the curing accelerator is preferably 0.01% by weight or more, more preferably 0.05% by weight or more, and is preferably 10% by weight or less, more preferably 5% by weight or less, based on 100% by weight of the curable resin composition.

[0018] The curable resin composition contains a compound having an alkylsilyl group or an alkoxysilyl group in the molecule. The use of the above compound in the thermosetting resin composition can increase bonding strength. Examples of the compound having an alkylsilyl group or an alkoxysilyl group in the molecule include organopolysiloxane, silsesquioxane, and alkoxysilane. Among these, a compound having a structure represented by the following structural formula (1), a compound having a structure represented by the following structural formula (2), or a cage silsesquioxane having 12 or less Si atoms in the cyclic structure is preferred, as these compounds further increase bonding strength and improve moisture resistance (bonding strength under high humidity).

[0019] [ka]

[0020] where R 1 and R 2 each independently represents a hydrogen atom or an arbitrary substituent, and n represents an integer of 0 or more and 100 or less.

[0021] In the above structural formula (1), n ​​is more preferably 3 or more, even more preferably 5 or more, and more preferably 30 or less, even more preferably 20 or less, since this makes it easier to increase the moisture resistance of the resulting cured product.

[0022] [ka]

[0023] where R 3 represents a hydrogen atom or an arbitrary substituent, j represents an integer of 1 or more and 40 or less, and k represents an integer of 1 or more and 40 or less.

[0024] In the structural formula (2), j is preferably 30 or less, more preferably 20 or less, and k is preferably 30 or less, more preferably 20 or less.

[0025] In the above structural formulas (1) and (2), R1 , R 2 and R 3 is preferably a substituent represented by the following structural formula (3). [ka] In formula (3), R 4 represents an alkylene group or an arylene group, provided that the arylene group may be substituted with an alkyl group having 1 to 30 carbon atoms. 1 indicates an amino group, a carboxy group, an acid anhydride group, an epoxy group, an imide group, or a maleimide group, and * indicates a bonding position.

[0026] The curable resin composition of the present invention may contain a film-forming agent. By using a film-forming agent, film-forming properties can be further improved. Examples of the film-forming agent include phenoxy resin, acrylic resin, polyimide resin, polyamide resin, and polyamideimide resin.

[0027] From the viewpoint of further enhancing film-forming properties, the content of the film-forming agent is preferably 0.1% by weight or more, more preferably 1% by weight or more, and is preferably 50% by weight or less, more preferably 40% by weight or less, based on 100% by weight of the curable resin composition.

[0028] Examples of additives other than the curing accelerator and film-forming agent include fillers, adhesion promoters, dispersants, surfactants, pigments, and dyes.

[0029] The content of silanol groups in the curable resin composition is 10 -3 It is preferably mol / g or less. Although silanol groups improve the bonding strength of substrates, they have the property of easily absorbing moisture. Therefore, if a large amount of silanol groups is present, moisture resistance decreases, which in turn can cause a decrease in bonding strength. On the other hand, in the present invention, silanol groups are introduced intensively onto the surface of the organic insulating layer through the activation process and the contact process with a basic aqueous solution, etc., described below. Therefore, by setting the content of silanol groups in the curable resin composition within the above range, the amount of silanol groups inside the organic insulating layer that do not contribute to improving bonding strength can be reduced, thereby improving moisture resistance. Methods for setting the silanol content within the above range include using organosilicon compounds that do not have silanol groups, such as those represented by the structural formulas (1) and (2), or organosilicon compounds with few silanol groups as the compound. The content of silanol groups is 10 -4 It is more preferable that the concentration is 10 mol / g or less. -5 It is more preferable that the concentration is 10 mol / g or less. -6 The lower limit of the silanol group content is preferably as low as possible from the viewpoint of further improving moisture resistance, and may be 0 mol / g. 29 Measurement can be performed at 25°C by Si-NMR (AvanceCore, Bruker or equivalent).

[0030] The first substrate is not particularly limited, and may be a circuit element on which elements and wiring are formed, such as a sensor circuit element provided with a pixel section (pixel region), a circuit element on which a peripheral circuit section such as a logic circuit that executes various signal processing related to the operation of the solid-state imaging device is mounted, a circuit element on which a peripheral circuit such as a memory circuit is mounted, a circuit board on which multiple chips are electrically connected, or a support substrate that supports the circuit element or the circuit board.

[0031] The organic insulating layer preferably has a storage modulus at 25° C. of 2.0 GPa or more. By setting the storage modulus at 25°C within the above range, the moisture resistance can be further improved. The storage modulus at 25°C is more preferably 2.5 GPa or more, and even more preferably 3.0 GPa or more. There is no particular upper limit to the storage modulus at 25°C, but from the viewpoint of obtaining a certain level of processing speed when polishing by CMP or the like, it is preferably 15 GPa or less. The storage modulus can be measured by the following method. A curable resin composition is applied to a release-treated PET film, and the solvent is dried in a circulating oven at 100°C for 2 minutes. The composition is then heated in a circulating oven at 140°C for 30 minutes to form an organic insulating layer with a thickness of 20 μm. The resulting organic insulating layer is measured for its storage modulus at 25°C using a dynamic viscoelasticity measuring device (DMA7100, manufactured by Hitachi High-Tech Corporation or equivalent) at a frequency of 10 Hz, a heating rate of 5°C / min, and a measurement range of 0 to 40°C.

[0032] Examples of methods for forming a film from the curable resin composition include spin coating, slit coating, and curtain coating. Alternatively, a film may be formed by first forming a film on a release-treated substrate film by solvent casting, supplying the film to the substrate surface by lamination, and then peeling off the release-treated substrate. The temperature at which the curable resin composition is cured depends on the type of thermosetting resin, but may be, for example, 80°C to 200°C.

[0033] When the substrate laminate obtained by the present invention is a substrate laminate obtained by hybrid bonding, the method for manufacturing the substrate laminate of the present invention includes a step of forming an electrode on the first substrate before the step of forming the organic insulating layer. The material of the electrodes is not particularly limited, and conventionally known electrode materials such as gold, copper, aluminum, etc. The electrodes are formed on the surface of the first substrate on which the organic insulating layer is to be formed.

[0034] The thickness of the electrodes is not particularly limited, but from the viewpoint of shortening the wiring distance while ensuring electrical connection reliability and reducing the thickness of the resulting substrate laminate, it is preferable that the thickness after the polishing step described below be 0.1 μm or more and 20 μm or less.

[0035] Examples of methods for forming the electrodes include sputtering, chemical vapor deposition, electrolytic plating, and electroless plating.

[0036] When the step of forming the electrodes has been carried out, the method for producing a substrate laminate of the present invention then carries out a step of polishing the bonding surface of the organic insulating layer (also referred to as a polishing step). By polishing the bonding surface of the organic insulating layer, the organic insulating layer formed on the electrode can be removed and the bonding surface can be planarized to improve bonding stability. The polishing is performed until the electrode is completely exposed. Examples of the polishing method include CMP (Chemical Mechanical Polishing) and flycutting. The polishing step is performed before the activation step and the contact step with a basic aqueous solution, etc., which will be described later.

[0037] The method for producing a substrate laminate of the present invention then carries out a step of activating the bonding surface of the organic insulating layer (also referred to as an activation step). Activating the bonding surface of the organic insulating layer removes foreign matter from the surface, thereby improving bonding stability. Examples of the activation method include plasma treatment. Examples of the plasma treatment include vacuum plasma treatment, gas irradiation atmospheric pressure plasma treatment, and discharge atmospheric pressure plasma treatment, with vacuum plasma treatment being preferred. Examples of gases introduced during plasma treatment include argon, oxygen, nitrogen, and hydrogen. Among these, oxygen or nitrogen is preferred because of its high reactivity with the subsequent aqueous silane coupling agent solution.

[0038] The method for producing a substrate laminate of the present invention then carries out a step of bringing a basic aqueous solution or pure water into contact with the bonding surface of the organic insulating layer (hereinafter also referred to as a basic aqueous solution or the like contact step). When the bonding surface is brought into contact with a basic aqueous solution or pure water, silanol groups are introduced into the compound on the surface, thereby increasing the bonding strength. Furthermore, since the activation step and the contact step with the basic aqueous solution or the like are performed only on the bonding surface of the organic insulating layer, silanol groups are introduced intensively on the surface of the organic insulating layer. As a result, the amount of silanol groups present inside the organic insulating layer can be made smaller than on the surface of the organic insulating layer, which makes it easier to increase the bonding strength of the bonding surface of the organic insulating layer while also increasing moisture resistance.

[0039] Examples of basic compounds constituting the basic aqueous solution include sodium hydroxide, potassium hydroxide, magnesium hydroxide, etc. Among these, sodium hydroxide is preferred because it is inexpensive and provides a high modification effect.

[0040] Examples of methods for contacting the basic aqueous solution or pure water with the bonding surfaces include applying the basic aqueous solution or pure water to the bonding surfaces by methods such as spin coating, slit coating, and curtain coating, then removing the basic aqueous solution or pure water, and drying the substrate. Alternatively, the entire substrate may be immersed in the basic aqueous solution or pure water, then removing the basic aqueous solution or pure water, and drying the bonding surfaces. The concentration of the basic compound in the basic aqueous solution is preferably 0.001N or more and 10N or less. By having the concentration of the basic aqueous solution in the above range, sufficient silanol groups can be introduced to the surfaces of the bonding surfaces, thereby further improving bonding stability. The concentration of the basic compound in the basic aqueous solution is more preferably 0.01N or more and more preferably 5N or less.

[0041] The basic aqueous solution or pure water may be contacted for 1 to 30 seconds at 15 to 30° C. (room temperature). By keeping the contact conditions within the above range, sufficient silanol groups can be introduced onto the surface of the bonding interface, thereby further improving bonding stability.

[0042] The activation step and the contact step with a basic aqueous solution or the like may be carried out consecutively, or other steps may be carried out in between, but it is preferable to carry them out consecutively. By carrying out the activation step and the contact step with a basic aqueous solution or the like consecutively, hydroxyl groups are rapidly introduced by the contact step with a basic aqueous solution or the like, so that silanol groups can be reliably introduced and production efficiency can be improved.

[0043] The method for producing a substrate laminate of the present invention then carries out a step of bonding the bonding surface of the organic insulating layer of the first substrate to a second substrate. A substrate laminate is obtained by bonding the organic insulating layer of the first substrate to the second substrate, which may be the same as the first substrate.

[0044] When the substrate laminate obtained by the present invention is a substrate laminate obtained by hybrid bonding, the bonding method may be thermocompression bonding, and the thermocompression bonding conditions may be, for example, 200 to 300°C, 1 to 60 minutes, and 1 to 10 MPa. The thermocompression bonding may be repeated multiple times.

[0045] In order to further improve the connectivity of the electrodes of the resulting substrate laminate, a heat treatment may be carried out after thermocompression bonding. Heating conditions for the heat treatment after thermocompression bonding include, for example, 200 to 400°C and 30 to 300 minutes.

[0046] Furthermore, when the substrate laminate obtained by the present invention is, for example, a laminate of a substrate having a plurality of chips and a support substrate, examples of the bonding method include a method in which the surfaces are chemically bonded by heat treatment, and examples of the heat treatment conditions include 300 to 400°C and 1 to 10 hours.

[0047] When the substrate laminate obtained by the present invention is a substrate laminate obtained by hybrid bonding, the method for manufacturing the substrate laminate of the present invention includes a step of forming an electrode on the second substrate before the step of joining the first substrate and the second substrate. The type of electrode and the method of forming the electrode are the same as those in the electrode forming process for the first substrate.

[0048] When the substrate laminate obtained by the present invention is a substrate laminate obtained by hybrid bonding, the method for manufacturing a substrate laminate of the present invention forms an insulating layer on the electrode surface of the second substrate before the step of joining the first substrate and the second substrate. The insulating layer may be an organic insulating layer or an inorganic insulating layer. Examples of materials for the inorganic insulating layer include SiO2, SiCN, and SiON. The inorganic insulating layer may be formed by, for example, PECVD (plasma enhanced chemical vapor deposition).

[0049] When the substrate laminate obtained by the present invention is a substrate laminate obtained by hybrid bonding, the method for producing a substrate laminate of the present invention includes a step of polishing the bonding surfaces of the insulating layers. The polishing is the same as the polishing step for the organic insulating layer on the first substrate. Although the effect of increasing the bonding strength can be achieved by performing the polishing step on at least one of the first substrate and the second substrate, it is preferable to perform the polishing step on both the first substrate and the second substrate in order to further increase the bonding strength.

[0050] When the substrate laminate obtained by the present invention is a substrate laminate obtained by hybrid bonding, the method for producing a substrate laminate of the present invention preferably includes subjecting the second substrate to the activation step and the basic aqueous solution or the like contact step. The details of the activation step and the contact step with a basic aqueous solution, etc. on the second substrate are the same as those of the activation step and the contact step with a basic aqueous solution, etc. on the first substrate. [Effects of the Invention]

[0051] According to the present invention, it is possible to provide a method for manufacturing a substrate laminate that has high bonding strength even when a resin material is used for the insulating layer. [Brief explanation of the drawings]

[0052] [Figure 1] 1A to 1C are schematic diagrams illustrating the manufacturing process of a substrate laminate by hybrid bonding. DETAILED DESCRIPTION OF THE INVENTION

[0053] The following examples will further illustrate the present invention, but the present invention is not limited to these examples.

[0054] (Synthesis of silicone skeleton-containing polyimide (n=6)) R of the above structural formula (1) 1 and R 2 is a substituent represented by the above structural formula (3), and R 4 is a trimethylene group, X 1 86 parts by weight of a silicone skeleton-containing organosilicon compound (KF-8010, manufactured by Shin-Etsu Silicones Co., Ltd.) in which n is an amino group and n is 6, and 31 parts by weight of 4,4'-oxydiphthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to 500 parts by weight of toluene, and the mixture was reacted at 60°C for 2 hours. After that, the mixture was refluxed at 110°C for 6 hours using a Dean-Stark reaction system, and the generated water was removed, yielding a silicone skeleton-containing polyimide (n=6) (solid content 18.9%).

[0055] (Synthesis of silicone skeleton-containing polyimide (n=16)) R of the above structural formula (1) 1 and R 2 is a substituent represented by the above structural formula (3), and R 4 is an alkylene group, X 1 160 parts by weight of a silicone skeleton-containing organosilicon compound (X-22-161A, manufactured by Shin-Etsu Silicones Co., Ltd.) in which n is an amino group and n is 16, and 31 parts by weight of 4,4'-oxydiphthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to 500 parts by weight of toluene, and the mixture was reacted at 60°C for 2 hours. After that, the mixture was refluxed at 110°C for 6 hours using a Dean-Stark reaction system, and the generated water was removed, yielding a silicone skeleton-containing polyimide (n=16) (solid content 27.6%).

[0056] (Synthesis of silicone skeleton-containing polyimide (n=35)) R of the above structural formula (1) 1 and R 2 is a substituent represented by the above structural formula (3), and R 4 is an alkylene group, X 1 300 parts by weight of a silicone skeleton-containing organosilicon compound (X-22-161B, manufactured by Shin-Etsu Silicones Co., Ltd.) in which n is an amino group and n is 35, and 31 parts by weight of 4,4'-oxydiphthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) were added to 500 parts by weight of toluene, and the mixture was reacted at 60°C for 2 hours. After that, the mixture was refluxed at 110°C for 6 hours using a Dean-Stark reaction system, and the generated water was removed, yielding a silicone skeleton-containing polyimide (n=35) (solid content 39.8%).

[0057] (Synthesis of silicone skeleton-containing bismaleimide (n=6)) R of the above structural formula (1) 1 and R 2 is a substituent represented by the above structural formula (3), and R 4 is a trimethylene group, X 1 To 86 parts by weight of a silicone skeleton-containing organosilicon compound (KF-8010, manufactured by Shin-Etsu Silicones Co., Ltd.) in which n is an amino group and n is 6, 19.6 parts by weight of maleic anhydride was added to 500 parts by weight of toluene, and the mixture was allowed to react at 60°C for 2 hours. After that, the mixture was refluxed at 110°C for 6 hours using a Dean-Stark reaction system, and the generated water was removed, yielding a silicone skeleton-containing bismaleimide (n=6) (solid content 17.4%).

[0058] (Synthesis of silane coupling agent B (containing silanol groups)) 90 parts by weight of methanol and 5 parts by weight of ultrapure water were added to 5 parts by weight of N-phenyl-3-aminopropylmethoxysilane (KBM-573, manufactured by Shin-Etsu Silicones Co., Ltd.), and the mixture was stirred at room temperature for 30 minutes to obtain silane coupling agent B (solid content 5.0%) in which some of the methoxy groups had been hydrolyzed to form silanol groups.

[0059] (Production of Epoxy Resin Composition) An epoxy-based thermosetting resin composition (referred to as "epoxy resin composition" in the tables) was obtained as the polymerizable compound by adding 50 parts by weight of a biphenyl aralkyl epoxy resin (NC3000, manufactured by Nippon Kayaku Co., Ltd.) as a polymerizable compound, 50 parts by weight of a bisphenol A epoxy resin (YL980, manufactured by Mitsubishi Chemical Corporation), 95 parts by weight of an active ester (HPC-8000-65T, manufactured by DIC Corporation) as a curing agent, and 5 parts by weight of imidazole (2E4MZ, manufactured by Shikoku Chemicals Co., Ltd.) as a curing accelerator to cyclohexanone and kneading them together.

[0060] (Production of Maleimide Resin Composition) A maleimide-based thermosetting resin composition (referred to as "maleimide resin composition" in the tables) was obtained as the polymerizable compound by adding 30 parts by weight of a biphenylaralkyl maleimide compound (MIR-3000-70T, manufactured by Nippon Kayaku Co., Ltd.) as a polymerizable compound, 30 parts by weight of bismaleimide (BMI689, manufactured by Design Molecules), 40 parts by weight of a styryl compound (OPE-2St, manufactured by SABIC) as a film-forming agent and curing agent, and 5 parts by weight of imidazole (2E4MZ, manufactured by Shikoku Kasei Co., Ltd.) as a curing accelerator to cyclohexanone and kneading them together.

[0061] (Production of curable resin composition) A curable resin composition (referred to as Resin A in Table 1) was obtained by kneading 70 parts by weight of the obtained epoxy resin composition, 5 parts by weight of the obtained silicone skeleton-containing polyimide (n=6), and 25 parts by weight of a phenoxy resin (YX6954BH30, manufactured by Mitsubishi Chemical Corporation) as a film-forming agent.

[0062] (Measurement of storage modulus of cured product at 25°C) The obtained curable resin composition was applied to a release-treated PET film using an applicator, and the solvent was dried in a circulating oven at 100°C for 2 minutes. Next, the film was heated in a circulating oven at 140°C for 30 minutes to form a cured product (organic insulating layer) of the curable resin composition with a thickness of 20 μm. The resulting cured product was measured for its storage modulus at 25°C using a dynamic viscoelasticity measuring device (DMA7100, manufactured by Hitachi High-Tech Corporation) at a frequency of 10 Hz, a heating rate of 5°C / min, and a measurement range of 0 to 40°C.

[0063] (Production of Curable Resin Compositions B to M (Resins B to M)) Resins B to M were obtained in the same manner as for Resin A, except that the compositions were as shown in Table 1, and the storage modulus of the cured products at 25° C. was measured. Details of each component in the table are as follows. Silicone skeleton-containing epoxy (n=7): R in the above structural formula (1) 1 and R 2 is a substituent represented by the above structural formula (3), and R 4 is an alkylene group, X 1 is an epoxy group and n is 7 (KF-105, manufactured by Shin-Etsu Silicones Co., Ltd.) Silicone skeleton-containing acid anhydride (n=8): R 1 and R 2 is a substituent represented by the above structural formula (3), and R 4 is an alkylene group, X 1 is an acid anhydride group and n is 8 (X-22-168AS, manufactured by Shin-Etsu Silicones Co., Ltd.) Silane coupling agent A: KBM-573, manufactured by Shin-Etsu Silicone Co., Ltd. Polyimide resin: PIAD300, manufactured by Arakawa Chemical Co., Ltd. Inorganic filler: Phenylsilane-treated spherical silica (Sciqas 0.1 μm, manufactured by Sakai Chemical Industry Co., Ltd.)

[0064] [Table 1]

[0065] Example 1 (1) Preparation of a substrate with an organic insulating layer The resulting curable resin composition was spin-coated onto the copper bump surface of a silicon wafer (WALTS-TEGFBW10-0001JY, manufactured by Waltz Corporation) with a surface SiO2 layer, 5 μm-high copper bumps, and 5 μm-sized bumps, to a thickness of 7 μm from the wafer surface after curing. The curable resin composition was then heat-treated in a circulating oven at 100°C for 2 minutes, followed by a further heat treatment at 160°C for 30 minutes to dry and cure the curable resin composition, forming an organic insulating layer. The organic insulating layer was then polished using a CMP system (ARW-8C1MS, manufactured by MAT Corporation) with a silica-blended slurry (COMPOL80, manufactured by Fujimi Incorporated), followed by finish polishing using a suede-type polishing pad. The substrate was then cleaned using a cleaning solution (CMP-B01, manufactured by Kanto Chemical Co., Ltd.) in a cleaning system (ZAB-8S1M, manufactured by MAT Corporation) to planarize the organic insulating layer and expose the Cu electrodes, yielding a substrate with an organic insulating layer.

[0066] (2) Preparation of a substrate with an inorganic insulating layer A silicon wafer (WALTS-TEGFBW10-0001JY, manufactured by Waltz Corporation) with a surface SiO2 layer, copper bumps 5 μm high, and a bump size of 5 μm was coated with a SiO2 film on the copper bump surface using a plasma CVD device (PD-220NL, manufactured by SAMCO Corporation) to a thickness of 5 μm from the wafer surface. Subsequent polishing and cleaning were carried out in the same manner as in the preparation of substrates with organic insulating layers, yielding substrates with inorganic insulating layers (referred to as inorganic in the table).

[0067] (3) Manufacturing of substrate laminate A substrate having an organic insulating layer was prepared as the first substrate. First, the bonding surface of the first substrate (the surface on the organic insulating layer and electrode side) was activated by O2 plasma treatment using a plasma treatment device (SAMCO OP-300). Next, a 0.5N NaOH aqueous solution was prepared as a basic aqueous solution, and the basic aqueous solution was contacted with the bonding surface using spin coating. The contact was performed for 5 seconds at 23°C, and the applied basic aqueous solution was completely removed by increasing the spin coating rotation speed. Meanwhile, a substrate having an inorganic insulating layer was prepared as the second substrate, and the activation process and basic aqueous solution contact process were performed in the same manner as for the first substrate. Then, the bonding surfaces of the first and second substrates were stacked so that the electrodes of the first and second substrates were connected. After that, the wafers were heated from room temperature to 200°C using a wafer bonding device (EVG510, EVG), and thermocompression bonding was performed for 60 minutes at 1 MPa. Next, a heat treatment was further performed in a circulating oven at 300°C for 30 minutes to obtain a substrate laminate.

[0068] (Examples 2 to 12, Comparative Examples 1 to 3) A substrate laminate was obtained in the same manner as in Example 1, except that the type of curable resin composition used, and whether or not an activation step and a basic solution contact step were performed were as shown in Table 2.

[0069] <Evaluation> The substrate laminates obtained in the examples and comparative examples were evaluated as follows. The results are shown in Table 2.

[0070] (Evaluation of initial bonding strength) The initial bonding strength of the bonded interface of the obtained substrate laminate was measured using the blade insertion method described in "Bonding of silicon wafers for silicon-on-insulator" W.P. Maszara, et al., Journal of Applied Physics 64, 4943 (1988), and evaluated according to the following criteria. ○: 2.0 J / m 2 End △: 1.0J / m 2 More than 2.0J / m 2 less than ×:1.0J / m2 less than

[0071] (Evaluation of bonding strength after moisture absorption reflow test) The obtained substrate laminate was subjected to a moisture absorption reflow test in accordance with IPC / JEDEC J-STD-020C MSL Level 3. Specifically, the substrate laminate was allowed to absorb moisture for 40 hours at 60°C and 60% RH, and then heated three times at a peak temperature of 260°C. The substrate laminate after the moisture absorption reflow test was evaluated in the same manner as in the evaluation of the initial bonding strength described above, and the bonding strength after the moisture absorption reflow test was evaluated.

[0072] [Table 2] [Industrial Applicability]

[0073] According to the present invention, it is possible to provide a method for manufacturing a substrate laminate that has high bonding strength even when a resin material is used for the insulating layer. [Explanation of symbols]

[0074] 1 First board 2 Second board 3 electrodes 4. Insulation layer

Claims

1. forming a curable resin composition on a first substrate and curing the composition to form an organic insulating layer; activating the bonding surface of the organic insulating layer; a step of contacting a basic aqueous solution or pure water with the activated bonding surface of the organic insulating layer; bonding a bonding surface of the organic insulating layer of the first substrate to a second substrate, The curable resin composition comprises a thermosetting resin and a compound having an alkylsilyl group or an alkoxysilyl group in the molecule.

2. The content of silanol groups in the curable resin composition is 10 －３ 2. The method for producing a substrate laminate according to claim 1, wherein the surface roughness is 0.05 mol / g or less.

3. The method for manufacturing a substrate laminate according to claim 1 or 2, wherein the compound has a structure represented by formula (1): 【Chemistry 1】 Here, R １ and R ２ each independently represents a hydrogen atom or an arbitrary substituent, and n represents an integer of 0 or more and 100 or less.

4. The method for manufacturing a substrate laminate according to claim 1 or 2, wherein the compound has a structure represented by formula (2): 【Chemistry 2】 Here, R ３ represents a hydrogen atom or an arbitrary substituent, j represents an integer of 1 or more and 40 or less, and k represents an integer of 1 or more and 40 or less.

5. 3. The method for manufacturing a substrate laminate according to claim 1, wherein the compound is a cage silsesquioxane having 12 or less Si atoms in the cyclic structure.

6. 3. The method for producing a substrate laminate according to claim 1, wherein the curable resin composition contains at least one resin selected from the group consisting of a phenoxy resin, a polyimide resin, a polyimide precursor, a polyamide resin, a bismaleimide, and an epoxy resin.

7. The method for producing a substrate laminate according to claim 1 or 2, wherein the organic insulating layer has a storage modulus at 25°C of 2.0 GPa or more.

8. 3. The method for manufacturing a substrate laminate according to claim 1, further comprising the step of forming an electrode on the first substrate before the step of forming the organic insulating layer.

9. 9. The method for manufacturing a substrate laminate according to claim 8, further comprising the steps of: forming an electrode on the second substrate; and forming an insulating layer on the electrode surface of the second substrate, before the step of bonding the first substrate and the second substrate.

10. The method for manufacturing a substrate laminate according to claim 9 , further comprising the step of polishing a bonding surface of at least one of the organic insulating layer and the insulating layer.

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