Manufacturing method for substrate laminate

Abstract

To provide a manufacturing method for a substrate laminate, for obtaining the substrate laminate using a hybrid bonding and having excellent durability, though a resin material is used for an insulating layer.SOLUTION: A manufacturing method for a substrate laminate includes steps of forming a first insulating layer 4 on an electrode surface of a first substrate 1 including an electrode 3, forming a second insulating layer on an electrode surface of a second substrate 2 including an electrode, forming a joint surface by polishing the first insulating layer and the second insulating layer, activating at least one joint surface of the first substrate and the second substrate, bringing a basic aqueous solution into contact with at least one joint surface of the first substrate and the second substrate, bringing a solution containing a coupling agent into contact with at least one joint surface of the first substrate and the second substrate, and joining the joint surface of the first substrate and the joint surface of the second substrate. At least one of the first insulating layer and the second insulating layer is an organic insulating layer.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 materials such as SiO2 have been considered for the insulating layer. However, the use of inorganic insulating layers has 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 (see, for example, Patent Documents 1 and 2). 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, thereby preventing bonding failure. Furthermore, because organic insulating layers are flexible, gaps are less likely to occur at the bond than when inorganic insulating layers are bonded together, which reduces moisture penetration and improves durability. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2021-197430 [Patent Document 2] Japanese Patent Publication No. 2023-039804 Summary of the Invention [Problem to be solved by the invention]

[0006] However, even when insulating layers are made of resin materials as in Patent Documents 1 and 2, their durability (bonding stability under harsh conditions and over long periods of time) is still not satisfactory, and there is a demand for substrate laminates that have excellent durability even when using resin materials for the insulating layers.

[0007] The present invention aims to provide a method for manufacturing a substrate laminate using hybrid bonding, which can obtain a substrate laminate that has excellent durability even when a resin material is used for the insulating layer. [Means for solving the problem]

[0008] The present invention is comprised of the following Disclosures 1 to 8. The present invention will be described in detail below. [Disclosure 1] forming a first insulating layer on an electrode surface of a first substrate having an electrode; forming a second insulating layer on an electrode surface of a second substrate having an electrode; polishing the first insulating layer and the second insulating layer to form a bonding surface; activating a bonding surface of at least one of the first substrate or the second substrate; bringing a basic aqueous solution into contact with at least one bonding surface of the first substrate or the second substrate; bringing a solution containing a coupling agent into contact with a bonding surface of at least one of the first substrate and the second substrate; bonding a bonding surface of the first substrate to a bonding surface of the second substrate; A method for manufacturing a substrate laminate, wherein at least one of the first insulating layer and the second insulating layer is an organic insulating layer. [Disclosure 2] In the step of activating the bonding surfaces, both the bonding surface of the first substrate and the bonding surface of the second substrate are activated; The method for manufacturing a substrate laminate according to Disclosure 1, wherein in the step of contacting the bonding surfaces with a basic aqueous solution, the basic aqueous solution is contacted with both the bonding surface of the first substrate and the bonding surface of the second substrate. [Disclosure 3] The method for manufacturing a substrate laminate according to Disclosure 1 or 2, wherein the first insulating layer and the second insulating layer are the organic insulating layer. [Disclosure 4] The method for producing a substrate laminate according to any one of Aspects 1 to 3, wherein the coupling agent is present in a hydrolyzed state in a solution containing the coupling agent. [Disclosure 5] 5. The method for producing a substrate laminate according to any one of Aspects 1 to 4, wherein the coupling agent has flux properties. [Disclosure 6] The method for producing a substrate laminate according to any one of Disclosures 1 to 5, wherein the coupling agent has at least one selected from the group consisting of a carboxy group, an acid anhydride group, an amino group, and an ester structure. [Disclosure 7] 7. The method for producing a substrate laminate according to any one of Disclosures 1 to 6, wherein the coupling agent is a silane coupling agent or a titanium coupling agent. [Disclosure 8] The method for producing a substrate laminate according to any one of Disclosures 1 to 7, wherein the organic insulating layer is a cured product of a curable resin composition, and 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 maleimide resin, and an epoxy resin.

[0009] The method for manufacturing a substrate laminate of the present invention first involves forming a first insulating layer on the electrode surface of a first substrate having an electrode, and then forming a second insulating layer on the electrode surface of a second substrate having an electrode. The first substrate and the second substrate are not particularly limited, and may be circuit elements 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, or a circuit element on which a peripheral circuit such as a memory circuit is mounted.

[0010] The material of the electrodes is not particularly limited, and conventionally known electrode materials such as gold, copper, aluminum, and nickel can be used.

[0011] 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.

[0012] At least one of the first insulating layer and the second insulating layer is an organic insulating layer. By using an organic insulating layer for at least one of the first insulating layer and the second insulating layer, foreign matter or voids trapped during substrate bonding can be filled, 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, thereby preventing moisture penetration and improving durability. While the organic insulating layer may be used for either the first insulating layer or the second insulating layer, it is preferable that both the first insulating layer and the second insulating layer be organic insulating layers, as this can further reduce bonding defects 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, as this provides high reliability. The curable resin composition may be either thermosetting or photocurable, but is preferably thermosetting. In other words, the curable resin composition preferably contains a thermosetting resin.

[0013] The thermosetting resin may be a resin containing a polymerizable compound and, if necessary, a curing agent. Since high-temperature treatment is performed during bonding of the substrates, 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, because of its excellent bonding strength. An epoxy resin or maleimide resin is more preferred, and a maleimide resin is even more preferred because of its particularly excellent moisture resistance.

[0014] 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.

[0015] The maleimide resin is preferably a polyfunctional maleimide resin, since it can easily increase the elastic modulus after curing. Examples of polyfunctional 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 phenylaralkyl-type maleimide compounds, tolylaralkyl-type maleimide compounds, and biphenylaralkyl-type maleimide compounds.

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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, polyamideimide resin, and silicone resin.

[0021] 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.

[0022] Examples of additives other than the curing accelerator and film-forming agent include fillers, adhesion promoters, dispersants, surfactants, pigments, and dyes.

[0023] When the first insulating layer or the second insulating layer is not an organic insulating layer, that is, is an inorganic insulating layer, examples of the material for the inorganic insulating layer include SiO2, SiCN, and SiON.

[0024] As a method for forming the insulating layer, for example, in the case of an organic insulating layer, a curable resin composition can be formed into a film by spin coating, slit coating, curtain coating, etc., and then cured. Alternatively, a film may be formed on a release-treated substrate film by solvent casting, and then the film may be applied to the substrate surface by lamination, and then the release-treated substrate may be peeled off to form a film. When the curable resin composition is thermosetting, the temperature at which the curable resin composition is cured is determined depending on the type of the thermosetting resin, and may be, for example, 80°C to 200°C.

[0025] When the insulating layer is an inorganic insulating layer, it can be formed by, for example, PECVD (plasma enhanced chemical vapor deposition).

[0026] The method for producing a substrate laminate of the present invention then carries out the step of polishing the first insulating layer and the second insulating layer to form bonding surfaces. By polishing the first and second insulating layers, the organic insulating layer formed on the electrode can be removed and the resulting bonding surface can be flattened to improve bonding stability. The polishing is continued until the electrode is completely exposed. Examples of the polishing method include CMP (Chemical Mechanical Polishing) and flycut processing.

[0027] The method for producing a substrate laminate of the present invention then carries out a step of activating the bonding surface of at least one of the first substrate and the second substrate (hereinafter also referred to as an activation step). By activating the bonding surface of at least one of the first substrate and the second substrate after the polishing step, foreign matter on the surface can be removed, thereby improving bonding stability. The activation step may be performed on at least one of the first substrate and the second substrate, but it is preferable to activate both the bonding surface of the first substrate and the bonding surface of the second substrate, as this further improves bonding strength.

[0028] The activation method may be, for example, a 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. Gases introduced during the plasma treatment include argon, oxygen, nitrogen, and hydrogen, among which oxygen or nitrogen is preferred because of its high reactivity with the subsequent aqueous silane coupling agent solution.

[0029] The method for producing a substrate laminate of the present invention then carries out a step of bringing a basic aqueous solution into contact with the bonding surface of at least one of the first substrate or the second substrate (hereinafter also referred to as a basic aqueous solution contacting step). When the bonding surface is brought into contact with a basic aqueous solution, hydroxyl groups are introduced onto the surface, and by bonding with a coupling agent (described later), the bonding strength is improved, thereby increasing durability. The contacting step may be performed on at least one of the first substrate and the second substrate, but it is preferable to bring the basic aqueous solution into contact with both the bonding surface of the first substrate and the bonding surface of the second substrate, as this further improves the bonding strength.

[0030] 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.

[0031] Examples of methods for contacting the basic aqueous solution with the bonding surfaces include applying the basic aqueous solution to the bonding surfaces by spin coating, slit coating, curtain coating, or the like, then removing the basic aqueous solution and drying the substrate. Alternatively, the entire substrate may be immersed in the basic aqueous solution, then removing the basic aqueous solution 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 hydroxyl groups can be introduced into 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.

[0032] The basic aqueous solution may be contacted for 1 to 30 seconds at 15 to 30° C. (room temperature). By contacting the materials under the above-mentioned conditions, sufficient hydroxyl groups can be introduced onto the surfaces of the bonding surfaces, thereby further improving bonding stability.

[0033] The activation step and the basic aqueous solution contact step 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 basic aqueous solution contact step consecutively, hydroxyl groups are rapidly introduced by the basic aqueous solution contact step, so that hydroxyl groups can be reliably introduced and production efficiency can be improved.

[0034] The method for manufacturing a substrate laminate of the present invention then carries out a step of contacting at least one of the bonding surfaces of the first substrate or the second substrate with a solution containing a coupling agent (hereinafter also referred to as a coupling agent contact step). By contacting the bonding surfaces with a coupling agent, the coupling agent crosslinks the first and second insulating layers when the substrates are bonded, thereby improving durability. Furthermore, in the present invention, the activation step and basic aqueous solution contact step are performed, and the coupling agent bonds with the hydroxyl groups introduced by the basic aqueous solution contact step, thereby improving durability compared to when a coupling agent is simply used. Furthermore, if both the first and second insulating layers are organic insulating layers and the activation step and basic aqueous solution contact step are performed on both insulating layers, the coupling agent more strongly crosslinks the two insulating layers, thereby improving durability.

[0035] The coupling agent contacting step may be carried out on the bonding surface of at least one of the first substrate and the second substrate, and is preferably carried out on the bonding surface of the substrate that has been subjected to the basic aqueous solution contacting step, since this allows a larger amount of coupling agent to bond with the hydroxyl groups introduced by the basic aqueous solution contacting step, thereby further increasing the bonding strength.

[0036] Examples of the coupling agent include a silane coupling agent, a titanium coupling agent, an aluminate coupling agent, etc. Among these, the coupling agent is preferably a silane coupling agent or a titanium coupling agent, as this can further enhance durability.

[0037] The coupling agent preferably has flux properties. Fluxing properties refer to the ability to remove oxide films and inhibit oxidation. If a coupling agent has fluxing properties, it can remove an oxide film formed on the electrode surface and inhibit oxidation even in areas without an oxide film, thereby preventing poor conduction and improving electrical connection reliability. Examples of coupling agents with fluxing properties include coupling agents having specific substituents or structures, and specific examples include coupling agents having a carboxy group, an acid anhydride group, an amino group, an ester structure, or the like. Among these, it is preferable that the coupling agent have at least one selected from the group consisting of a carboxy group, an acid anhydride group, an amino group, and an ester structure, as this can further improve electrical connection reliability.

[0038] The coupling agent is preferably present in a hydrolyzed state in a solution containing the coupling agent. The coupling agent in the solution containing the coupling agent is in a hydrolyzed state, which further enhances the reactivity with the bonding surface after the basic aqueous solution contact step. As a method for hydrolyzing the coupling agent, for example, a method using water as a solvent for dissolving the coupling agent can be mentioned.

[0039] The solvent for the solution containing the coupling agent is not particularly limited as long as it can uniformly dissolve or disperse the coupling agent, but water is preferably used because it allows the coupling agent to exist in a hydrolyzed state as described above. Examples of solvents for the solution containing the coupling agent other than water include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, ethylene glycol, and glycerin.

[0040] Examples of methods for contacting the bonding surfaces with the solution containing the coupling agent include applying the solution containing the coupling agent to the bonding surfaces by methods such as spin coating, slit coating, and curtain coating, then removing the solution and drying the substrate. The concentration of the coupling agent in the solution containing the coupling agent is preferably 0.001 wt % or more, more preferably 0.01 wt % or more, and preferably 10 wt % or less, and more preferably 5 wt % or less, from the viewpoint of adequate crosslinking between the two insulating layers. The conditions for contacting the bonding surfaces with the solution containing the coupling agent are the same as those in the basic aqueous solution contact step.

[0041] The method for producing a substrate laminate of the present invention then carries out the step of bonding the bonding surface of the first substrate and the bonding surface of the second substrate. The bonding surfaces of the first substrate and the second substrate are placed one on top of the other and thermocompression bonded to bond the electrodes and insulating layers (first insulating layer, second insulating layer) of the two substrates, thereby obtaining a substrate laminate. Examples of thermocompression bonding conditions for bonding the first substrate and the second substrate include 200 to 300°C, 1 to 60 minutes, and 1 to 10 MPa. The thermocompression bonding may be repeated multiple times.

[0042] 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. [Effects of the Invention]

[0043] According to the present invention, it is possible to provide a method for manufacturing a substrate laminate using hybrid bonding, which can obtain a substrate laminate having excellent bonding stability even when a resin material is used for the insulating layer. [Brief explanation of the drawings]

[0044] [Figure 1] 1A to 1C are schematic diagrams illustrating the manufacturing process of a substrate laminate by hybrid bonding. DETAILED DESCRIPTION OF THE INVENTION

[0045] The following examples will further illustrate the present invention, but the present invention is not limited to these examples.

[0046] (Production of Curable Resin Composition) A curable resin composition was obtained by adding 40 parts by weight of NC3000 (biphenylaralkyl epoxy resin, manufactured by Nippon Kayaku Co., Ltd.) as a polymerizable compound, 40 parts by weight of YL980 (bisphenol A epoxy resin, manufactured by Mitsubishi Chemical Corporation), 5 parts by weight of 2P4MZ (imidazole, manufactured by Shikoku Chemical Industry Co., Ltd.) as a curing accelerator, 20 parts by weight of YX6954BH30 (manufactured by Mitsubishi Chemical Corporation) as a film-forming agent, and 80 parts by weight of HPC-8000-65T (active ester, manufactured by DIC Corporation) as a curing agent to cyclohexanone and kneading them together.

[0047] (Preparation of a substrate having 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 and copper bumps 5 μm high and 5 μm in size, to a thickness of 7 μm from the wafer surface after curing. The curable resin composition was then heat-treated in a convection 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 with a silica-blended slurry (COMPOL80, manufactured by Fujimi Incorporated) using a CMP system (ARW-8C1MS, manufactured by MAT Corporation) and then washed with a cleaning solution (CMP-B01, manufactured by Kanto Chemical Co., Ltd.) using a cleaning system (ZAB-8S1M, manufactured by MAT Corporation). This planarized the organic insulating layer and exposed the Cu electrodes, yielding a substrate with an organic insulating layer (referred to as "organic" in the table).

[0048] (Preparation of a substrate having 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).

[0049] Example 1 (1) Preparation of coupling agent solution While stirring a mixed solvent consisting of 90 ml of ultrapure water and 10 ml of methanol, 0.5 ml of a coupling agent (KBM-573, a silane coupling agent having an aminophenyl group, manufactured by Shin-Etsu Silicones Co., Ltd.) was gradually added dropwise, and stirring was continued for 1 hour after the completion of the addition to prepare a hydrolyzed coupling agent solution.

[0050] (2) Manufacturing of substrate laminate A substrate having the obtained 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 time was 5 seconds at 23°C, and the applied basic aqueous solution was completely removed by increasing the spin coating rotation speed. Next, the obtained coupling agent solution was contacted with the bonding surface using spin coating. The contact time was 5 seconds at 23°C, and the applied coupling agent solution was completely removed by increasing the spin coating rotation speed, as with the basic aqueous solution. Meanwhile, a substrate having an inorganic insulating layer was prepared as the second substrate, and the activation process, basic aqueous solution contact process, and coupling agent contact process were performed in the same manner as for the first substrate. The bonding surfaces of the first and second substrates were then stacked so that the electrodes of the first and second substrates were connected, and the temperature was raised from room temperature to 200°C using a wafer bonding device (EVG510, manufactured by EVG Corporation), followed by thermocompression bonding at 1 MPa for 60 minutes. This was followed by a further heat treatment in a circulating oven at 300°C for 30 minutes, yielding a substrate laminate.

[0051] (Examples 2 to 10, Comparative Examples 1 to 4) A substrate laminate was obtained in the same manner as in Example 1, except that the types of the first substrate and the second substrate, whether or not an activation step and a basic solution contact step were performed, whether or not a coupling agent was used, the type of solvent in the coupling agent-containing solution, and whether or not the coupling agent had fluxing properties were as shown in Table 1. Details of the coupling agents in the table are as follows. KBM-503: Silane coupling agent with methacrylic group, manufactured by Shin-Etsu Silicone Co., Ltd. KBM-603: Silane coupling agent with amino group, manufactured by Shin-Etsu Silicone Co., Ltd. KBM-103: Silane coupling agent with a phenyl group, manufactured by Shin-Etsu Silicone Co., Ltd. KBM-1003: Vinyltrimethoxysilane (silane coupling agent), manufactured by Shin-Etsu Silicone Co., Ltd. X-12967C: Silane coupling agent with acid anhydride group, manufactured by Shin-Etsu Silicone Co., Ltd.

[0052] <Evaluation> The substrate laminates obtained in the examples and comparative examples were evaluated as follows. The results are shown in Table 1.

[0053] (Evaluation of initial bonding strength) The initial bond 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 was evaluated according to the following criteria. The measurement limit of the bond strength was 2.5 J / m. 2 Therefore, 2.5J / m 2 Anything over 2.5J / m 2 " is written. ○: 2.0 J / m 2 End △: 1.0J / m 2 More than 2.0J / m 2 less than ×:1.0J / m 2 less than

[0054] (Evaluation of initial electrode adhesion) Three arbitrary electrode bonded portions of the obtained substrate laminate were observed at a magnification of 150,000 times using an FIB-SEM. The bonded electrode with the worst bonded state at the three observed positions was selected as the evaluation subject and evaluated according to the following criteria. ○: No interface, cracks, or peeling was observed over the entire electrode bonding interface. △: Interfaces, cracks, and peeling less than 2 μm in total were observed at the electrode bonding interface. ×: Interfaces, cracks, or peeling of 2 um or more were observed at the electrode bonding interface.

[0055] (Evaluation of bonding strength and electrode bonding after durability test) The obtained substrate laminate was subjected to a moisture absorption reflow test in accordance with MSL Level 3 of IPC / JEDEC J-STD-020C. Specifically, the substrate laminate was subjected to moisture absorption at 60°C and 60% RH for 40 hours, and then heated three times at a peak temperature of 260°C. Next, a temperature cycle test was performed in which the temperature was changed between -40°C and 125°C for 1000 cycles. The holding time for each temperature was 30 minutes. The substrate laminate after the moisture absorption reflow test and temperature cycle test (durability test) was evaluated in the same manner as the evaluation of the initial bond strength and initial electrode bondability described above, and the bond strength and electrode bondability after the durability test were evaluated.

[0056] [Table 1] [Industrial Applicability]

[0057] According to the present invention, it is possible to provide a method for manufacturing a substrate laminate using hybrid bonding, which can obtain a substrate laminate that has excellent durability even when a resin material is used for the insulating layer. [Explanation of symbols]

[0058] 1 First board 2 Second board 3 electrodes 4. Insulation layer

Claims

1. forming a first insulating layer on an electrode surface of a first substrate having an electrode; forming a second insulating layer on an electrode surface of a second substrate having an electrode; polishing the first insulating layer and the second insulating layer to form a bonding surface; activating a bonding surface of at least one of the first substrate or the second substrate; bringing a basic aqueous solution into contact with at least one bonding surface of the first substrate or the second substrate; bringing a solution containing a coupling agent into contact with a bonding surface of at least one of the first substrate and the second substrate; bonding a bonding surface of the first substrate to a bonding surface of the second substrate; A method for manufacturing a substrate laminate, wherein at least one of the first insulating layer and the second insulating layer is an organic insulating layer.

2. In the step of activating the bonding surfaces, both the bonding surface of the first substrate and the bonding surface of the second substrate are activated; The method for manufacturing a substrate laminate according to claim 1 , wherein the step of bringing the bonding surfaces into contact with the basic aqueous solution includes bringing the basic aqueous solution into contact with both the bonding surface of the first substrate and the bonding surface of the second substrate.

3. The method for manufacturing a substrate laminate according to claim 1 or 2, wherein the first insulating layer and the second insulating layer are the organic insulating layers.

4. The method for producing a substrate laminate according to claim 1 or 2, wherein the coupling agent is present in a hydrolyzed state in a solution containing the coupling agent.

5. The method for manufacturing a substrate laminate according to claim 1 or 2, wherein the coupling agent has a flux property.

6. 3. The method for producing a substrate laminate according to claim 1, wherein the coupling agent has at least one selected from the group consisting of a carboxy group, an acid anhydride group, an amino group, and an ester structure.

7. 3. The method for manufacturing a substrate laminate according to claim 1, wherein the coupling agent is a silane coupling agent or a titanium coupling agent.

8. 3. The method for producing a substrate laminate according to claim 1 or 2, wherein the organic insulating layer is a cured product of a curable resin composition, and 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 maleimide resin, and an epoxy resin.

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