substrate stack

Abstract

This substrate laminate includes a first substrate, a bonding layer containing a resin, and a second substrate arranged in this order, wherein the first substrate and the second substrate are both thicker than the bonding layer, and when composition analysis is performed on a cross section of the substrate laminate by means of an energy dispersive X-ray spectroscopy, an Si ratio, which is a value obtained by dividing the maximum value of an abundance ratio of Si atoms in the bonding layer by the minimum value of the abundance ratio of Si atoms in the bonding layer, is 1.5 or more.

Description

Technical Field

[0001] This disclosure relates to a substrate laminate.

Background Art

[0002] In recent years, studies have been made on substrate laminates formed by joining substrates together. For example, Patent Document 1 discloses a method for manufacturing a semiconductor device in which a first semiconductor wafer and a second semiconductor wafer are laminated as a substrate laminate.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2012-174937

Summary of the Invention

Problems to be Solved by the Invention

[0004] There are cases where it is required to further improve the bonding strength between substrates in a substrate laminate formed by joining substrates together. Here, the concept of "substrates joined together" means that the substrates are joined directly or through another layer.

[0005] This disclosure has been made in view of the above. An object of one aspect of this disclosure is to provide a substrate laminate having excellent bonding strength between substrates.

Means for Solving the Problems

[0006] Specific means for solving the above problems include the following aspects. <1> A first substrate, A resin layer containing a resin, A second substrate, A substrate laminate including them in this order of arrangement, Both the first substrate and the second substrate are thicker than the resin layer, The resin contains Si atoms, When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the Si ratio, which is the value obtained by dividing the maximum value of the Si atom abundance in the resin layer by the minimum value of the Si atom abundance in the resin layer, is 1.5 or greater. A laminated substrate. <2> The resin further contains oxygen atoms, When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the O ratio, which is the value obtained by dividing the maximum value of the O atom abundance in the resin layer by the minimum value of the O atom abundance in the resin layer, is 1.3 or greater. <1> The substrate laminate described above. <3> The first substrate and A resin layer containing resin, The second circuit board, A substrate laminate comprising the following in this order: Both the first substrate and the second substrate are thicker than the resin layer. The resin contains an O atom, When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the O ratio, which is the value obtained by dividing the maximum value of the O atom abundance in the resin layer by the minimum value of the O atom abundance in the resin layer, is 1.3 or greater. A laminated substrate. <4> When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the change in the ratio of oxygen atoms in the resin layer with respect to the thickness of the resin layer is continuous. <1> ~ <3> A substrate laminate as described in any one of the following. <5> When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the change in the ratio of Si atoms in the resin layer with respect to the thickness of the resin layer is continuous. <1> ~ <4> A substrate laminate as described in any one of the following. <6> The composite modulus of the aforementioned resin layer is 1 GPa to 20 GPa. <1> ~ <5> A substrate laminate as described in any one of the following. <7> Between the first substrate and the second substrate, further, an electrode is provided that penetrates the resin layer. <1> ~ <6> A substrate laminate as described in any one of the following. <8> Each of the first substrate and the second substrate includes an inorganic substrate body and an inorganic layer. <1> ~ <7> A substrate laminate as described in any one of the following. [Effects of the Invention]

[0007] According to one aspect of this disclosure, a substrate laminate is provided that exhibits excellent bonding strength between substrates. [Brief explanation of the drawing]

[0008]

Figure 1

[0009] In this disclosure, a numerical range represented by "~" means a range that includes the numbers written before and after "~" as the lower and upper limits, respectively. In numerical ranges described in stages within this disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in numerical ranges described within this disclosure, the upper or lower limit of that range may be replaced with the values ​​shown in the examples.

[0010] The substrate laminates of this disclosure (the substrate laminate of the first embodiment and the substrate bond of the second embodiment) will be described below.

[0011] The substrate laminate of the first embodiment of this disclosure is The first substrate and A resin layer containing resin, The second circuit board, A substrate laminate comprising the following in this order: Both the first substrate and the second substrate are thicker than the resin layer. The resin contains Si atoms, When the cross-section of the substrate laminate is analyzed for composition by energy-dispersive X-ray spectroscopy, the Si ratio, which is the value obtained by dividing the maximum value of the Si atom abundance in the resin layer (hereinafter also referred to as "Si ratio") by the minimum value of the Si atom abundance in the resin layer (i.e., the Si ratio) (i.e., maximum Si ratio / minimum Si ratio), is 1.5 or greater. It is a substrate laminate.

[0012] The substrate laminate of the first embodiment has a Si ratio of 1.5 or higher, which results in excellent bonding strength between the substrates (specifically, the bonding strength between the first substrate and the second substrate bonded via a resin layer).

[0013] The substrate laminate of the first embodiment exhibits excellent bonding strength between substrates (hereinafter also simply referred to as "bonding strength at low temperatures") even when the substrates are bonded together at low temperatures (e.g., 140°C or below) during the manufacturing process.

[0014] The substrate laminate of the second embodiment of this disclosure is The first substrate and A resin layer containing resin, The second circuit board, A substrate laminate comprising the following in this order: Both the first substrate and the second substrate are thicker than the resin layer. The resin contains oxygen atoms, When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the O ratio, which is the value obtained by dividing the maximum value of the O atom abundance in the resin layer (hereinafter also referred to as "O ratio") by the minimum value of the O atom abundance in the resin layer (i.e., the O ratio) (i.e., maximum O ratio / minimum O ratio), is 1.3 or greater. It is a substrate laminate.

[0015] The substrate laminate of the second embodiment has an O ratio of 1.3 or higher, which results in excellent bonding strength between substrates (specifically, the bonding strength between the first substrate and the second substrate bonded via a resin layer).

[0016] The substrate laminate of the second embodiment exhibits excellent bonding strength between substrates (hereinafter also simply referred to as "bonding strength at low temperatures") even when the substrates are bonded together at low temperatures (e.g., 140°C or below) during the manufacturing process.

[0017] The first and second embodiments may have overlapping portions. That is, the substrate laminate of the first embodiment may possess the characteristics of the substrate laminate of the second embodiment (i.e., the characteristics relating to the O atoms), and the substrate laminate of the second embodiment may possess the characteristics of the substrate laminate of the first embodiment (i.e., the characteristics relating to the Si atoms). The following description will focus on the substrate laminate of the first embodiment.

[0018] [Laminated substrate (first embodiment)] The substrate laminate of the first embodiment includes a first substrate, a resin layer having a thickness of 20 μm or less and containing resin, and a second substrate, arranged in this order. The substrate laminate of the first embodiment may include, if necessary, a first substrate, a second substrate, and other layers besides the resin layer.

[0019] <First substrate> The substrate laminate of the first embodiment includes a first substrate. The first substrate is a substrate whose thickness is greater than the thickness of the resin layer. The material of the first substrate is not particularly limited and can be any commonly used material.

[0020] The first substrate preferably contains at least one element selected from the group consisting of Si, Al, Ti, Zr, Hf, Fe, Ni, Cu, Ag, Au, Ga, Ge, Sn, Pd, As, Pt, Mg, In, Ta, and Nb, and is preferably a semiconductor substrate containing at least one element selected from the group consisting of Si, Ga, Ge, and As.

[0021] Specifically, the material of the first substrate may be, for example; Semiconductors such as Si, InP, InAs, GaN, GaP, GaAs, InGaAs, InGaAlAs, SiGe, and SiC; Oxides, carbides, or nitrides of borosilicate glass (Pyrex®), quartz glass (SiO2), sapphire (Al2O3), ZrO2, Si3N4, AlN, MgAl2O4, etc. BaTiO3, LiNbO3, SrTiO3, LiTaO3, Gadolinium gallium garnet (Gd3Ga5O 12 ), piezoelectric or dielectric materials such as; diamond; Metals such as Al, Ti, Fe, Cu, Ag, Au, Pt, Pd, Ta, Nb; carbon; Resins such as polydimethylsiloxane (PDMS), epoxy resins, phenolic resins, polyimides, benzocyclobutene resins, and polybenzoxazoles; These are some examples.

[0022] The main applications of the first substrate containing each material are as follows: Si is used in semiconductor memory, LSIs, CMOS image sensors, MEMS, optical devices, LEDs, and more. SiO2 is used in MEMS encapsulation, microfluidics, 2.5D packaging interposers, displays, and other applications. BaTiO3, LiNbO3, SrTiO3, LiTaO3, Gd3Ga5O 12 It is used in surface acoustic wave devices, etc. PDMS is used in applications such as microfluidics. InGaAlAs, InGaAs, and InP are used in optical devices and other applications. InGaAlAs, GaAs, and GaN are used in LEDs and other applications.

[0023] Regarding the material of the first substrate, for example; Publicly available documents such as the descriptions in paragraphs 0097-0098 of International Publication No. 2022 / 54839; See also information from https: / / www.jstage.jst.go.jp / article / ejisso / 22a / 0 / 22a_0_233 / _pdf, http: / / www.musashino-eng.co.jp / setsugou / img / sabsample.pdf, etc. You may also refer to this.

[0024] The thickness of the first substrate is not particularly limited, as long as it is greater than the thickness of the resin layer. The thickness of the first substrate is, for example, 50 μm or more, preferably 50 μm to 10 mm, preferably 100 μm to 5 mm, and more preferably 200 μm to 1 mm.

[0025] The first substrate may include an inorganic substrate body and an inorganic layer. Examples of materials for the inorganic substrate body include the materials for the first substrate exemplified above (excluding resin) (i.e., semiconductors, oxides, carbides, or nitrides, piezoelectric materials or dielectrics, metals, and carbon), and are preferably semiconductors, and particularly preferably Si. The inorganic layer is preferably an SiO2 layer, a SiCN layer, or a SiN layer, and is particularly preferably an SiO2 layer.

[0026] The inorganic layer can be formed by vapor phase growth methods such as sputtering, CVD, and ALD. Furthermore, the inorganic layer can also be formed as a native oxide film (specifically, an SiO2 layer).

[0027] The thickness of the inorganic substrate body is, for example, 50 μm or more, preferably 50 μm to 10 mm, preferably 100 μm to 5 mm, and more preferably 150 μm to 2 mm. The thickness of the inorganic layer is, for example, 1 nm to 10 μm, preferably 3 nm to 5 μm, and more preferably 5 nm to 1 μm.

[0028] <Second substrate> The substrate laminate of the first embodiment includes a second substrate. The second substrate is a substrate whose thickness is greater than the thickness of the resin layer. The material of the second substrate is not particularly limited and can be any commonly used material. Specific examples and preferred embodiments of the second substrate are the same as those of the first substrate. However, the first substrate and the second substrate may be identical or different in at least one of the following: material, shape, size, and physical properties. For example, the coefficient of thermal expansion (CTE) of the first substrate and the coefficient of thermal expansion (CTE) of the second substrate may be identical or different.

[0029] Generally, when stacking a first substrate and a second substrate with different CTEs, there is a risk of damage to the first substrate and / or the second substrate due to warping and stress during heating for stacking. In this regard, the substrate laminate of this disclosure exhibits excellent bonding strength at low temperatures, and therefore, bonding at low temperatures can suppress damage to the first substrate and / or the second substrate.

[0030] Because the substrate laminate of this disclosure exhibits excellent bonding strength at low temperatures, thermally weak substrates such as polyimide, GaAs, glass, LiNbO3, InGaAs, and InGaAlAs can be used as the first and / or second substrates.

[0031] Furthermore, because the substrate laminate of this disclosure exhibits excellent bonding strength at low temperatures, it can be applied to optical devices, thermally sensitive devices (e.g., phase-change memory), and the like.

[0032] <Resin layer> The substrate laminate of the first embodiment includes a resin layer containing resin. The resin layer is placed between the first substrate and the second substrate.

[0033] The resin layer may have a single-layer structure or a laminated structure consisting of multiple layers. The resin layer may be a layer formed by joining multiple layers. In this case, the interfaces between the multiple joined layers may remain clearly visible in the resin layer (i.e., the laminated structure may be maintained), or the interfaces between the multiple joined layers may fuse together and become indistinct (for example, a single-layer structure may be formed).

[0034] The thickness of the resin layer is 50 μm or less. The thickness of the resin layer is preferably 0.01 μm to 50 μm, more preferably 0.02 μm to 35 μm, and even more preferably 0.03 μm to 20 μm.

[0035] The resin contained in the resin layer is a resin containing Si atoms. The resin layer may contain only one type of resin or two or more types. If the resin layer contains two or more types of resin, it is sufficient that at least one of the resins contains Si atoms. The resin contained in the resin layer is, for example, at least one selected from the group consisting of polyimide, polyamide, polyamideimide, maleimide resin, parylene, polyalylene ether polyimide, polybenzoxazole, benzocyclobutene (BCB) resin, and epoxy resin. In this example, at least one of the resins contains Si atoms. Furthermore, the resin contained in the resin layer may also be a cured product of composition A or a cured product of composition B, which will be described later.

[0036] The resin layer can be formed by a coating method using a coating solution containing at least one of a resin and a resin precursor (e.g., a monomer) (i.e., a method of applying the coating solution and then heating it). Examples of coating solutions include compositions A and B, which will be described later.

[0037] From the viewpoint of further improving the bonding strength between substrates, the resin contained in the resin layer is more preferably to contain oxygen atoms, and even more preferably to contain at least one of a silanol group and a siloxane bond.

[0038] The resin contained in the resin layer is preferably at least one selected from the group consisting of siloxane bonds, amide bonds, and imide bonds. This further improves the bonding strength between the substrates. A resin layer comprising at least one selected from the group consisting of siloxane bonds, amide bonds, and imide bonds can be formed, for example, using composition A or composition B described later.

[0039] The resin layer may contain components other than resin. The resin layer preferably contains resin as its main component. Here, the main component refers to the component that has the highest mass-based content ratio. The resin content relative to the entire resin layer is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 80% by mass or more, and even more preferably 90% by mass or more. The resin content relative to the entire resin layer may be 100% by mass or less than 100% by mass.

[0040] (Si ratio) When the cross-section of the substrate laminate of this disclosure is subjected to compositional analysis by energy-dispersive X-ray spectroscopy (hereinafter also referred to as "EDX"), the Si ratio (i.e., the value obtained by dividing the maximum value of the Si atom abundance in the resin layer by the minimum value of the Si atom abundance in the resin layer; i.e., maximum Si ratio / minimum Si ratio) is 1.5 or greater. This improves the bonding strength between the substrates. The Si ratio (i.e., the maximum Si ratio / minimum Si ratio) is preferably 1.5 to 5.0, more preferably 1.6 to 3.0, and even more preferably 1.7 to 2.5.

[0041] In compositional analysis by EDX, there are no particular restrictions on the minimum value of the Si atom abundance (i.e., Si ratio), but for example, it is between 0.1 atom% and 30 atom%; preferably between 0.5 atom% and 20 atom%; and more preferably between 1 atom% and 10 atom%.

[0042] In this disclosure, the measurement conditions for energy-dispersive X-ray spectroscopy (EDX) can be found in the examples described later.

[0043] (Surface activation treatment) Specific means to achieve a Si ratio of 1.5 or higher include applying a surface activation treatment to the bonding surface of the resin layer before bonding the first substrate and the second substrate via the resin layer during the manufacturing stage of the substrate laminate. When a surface activation treatment is applied to the bonding surface of a resin layer, the relative abundance of Si atoms in the vicinity of the surface-activated surface (more specifically, in the vicinity in the thickness direction of the resin layer) can be increased. This results in locations where the Si atom ratio is at its maximum and minimum, making it easier to achieve an Si ratio of 1.5 or higher. For example, if plasma treatment, described later, is applied to the bonding surface of a resin layer as a surface activation treatment, the relative abundance of carbon (C) near the surface that has undergone the surface activation treatment can be reduced, and as a result, the relative abundance of Si in the same vicinity can be increased.

[0044] The surface activation treatment may be applied not only to the bonding surface in the resin layer (i.e., the surface of the resin layer), but also to the surface to be bonded to the resin layer.

[0045] Examples of bonding surfaces in the resin layer include: The bonding surface of the resin layer to the first substrate or the second substrate (hereinafter also simply referred to as the substrate); The bonding surface between the substrate and the resin layer or inorganic layer provided on the substrate; These are some examples. For example, when a laminate including a first substrate and a resin layer is bonded to a second substrate in a direction where the resin layer and the second substrate are in contact, the "bonding surface in the resin layer" is the bonding surface in the resin layer with the second substrate. Furthermore, when a laminate containing a first substrate and resin layer A and a laminate containing a second substrate and resin layer B are bonded together in a direction where resin layer A and resin layer B are in contact, the "bonding surface on resin layer A" is the bonding surface on resin layer A with resin layer B.

[0046] Surface activation treatments applied to the bonding surfaces of resin layers include chemical treatment, Si impregnation treatment, plasma treatment, high-speed atomic beam irradiation, and ozone treatment.

[0047] Examples of Si impregnation treatments include the application of a liquid containing a silane coupling agent.

[0048] The plasma treatment is, for example, at least one selected from the group consisting of oxygen plasma treatment and nitrogen plasma treatment.

[0049] In a plasma treatment which is at least one selected from the group consisting of oxygen plasma treatment and nitrogen plasma treatment, the gas flow rate of oxygen gas or nitrogen gas is preferably 5 sccm to 200 sccm, more preferably 10 sccm to 100 sccm, and even more preferably 10 sccm to 60 sccm.

[0050] The processing pressure in plasma processing is preferably 10 Pa to 100 Pa, more preferably 20 Pa to 80 Pa.

[0051] The RF power used in plasma processing is preferably 10W to 200W, more preferably 20W to 150W.

[0052] The processing time in plasma processing is preferably 10 to 200 seconds, more preferably 20 to 100 seconds.

[0053] During the manufacturing stage of the substrate laminate, the surface of the resin layer after surface activation treatment may be washed with water.

[0054] (Changes in the abundance of Si atoms) In the first embodiment, EDXWhen compositional analysis is performed using this method, it is preferable that the change in the ratio of Si atoms in the resin layer along the thickness direction of the resin layer is continuous. This further improves the bonding strength between substrates.

[0055] In this disclosure, "the change in the ratio of Si atoms in the resin layer with respect to the thickness of the resin layer is continuous" means that the amount of change in the ratio of Si atoms per 1 nm of resin layer thickness is 1 atom% or less.

[0056] One way to achieve the condition that "the change in the ratio of Si atoms in the resin layer along the thickness direction of the resin layer is continuous" is to apply the aforementioned plasma treatment to the bonding surface of the resin layer.

[0057] (O ratio ratio) When a cross-section of the substrate laminate of this disclosure is subjected to compositional analysis by EDX, the O ratio (i.e., the value obtained by dividing the maximum value of the O atom abundance in the resin layer by the minimum value of the O atom abundance in the resin layer; i.e., maximum value / minimum value) is 1.3 or greater. This further improves the bonding strength between the substrates. The O ratio (maximum / minimum value) is preferably 1.3 to 5.0, more preferably 1.4 to 3.0, and even more preferably 1.5 to 2.0.

[0058] In the compositional analysis by EDX described above, there are no particular restrictions on the minimum value of the oxygen atom's abundance, but for example, it is between 1 atom% and 50 atoms, preferably between 2 atoms% and 40 atoms, and more preferably between 3 atoms% and 30 atoms.

[0059] (Change in the abundance ratio of oxygen atoms) In the first embodiment, EDX When compositional analysis is performed, it is preferable that the change in the ratio of oxygen atoms in the resin layer along the thickness direction of the resin layer is continuous. This further improves the bonding strength between the substrates. The meaning of "continuous" in the context of changes in the abundance ratio of oxygen atoms is the same as the meaning of "continuous" in the context of changes in the abundance ratio of silicon atoms.

[0060] One way to achieve the condition that "the change in the relative abundance of oxygen atoms in the resin layer along the thickness direction of the resin layer is continuous" is to apply the aforementioned plasma treatment to the bonding surface of the resin layer.

[0061] (Ratio of C atoms) The resin in the resin layer naturally contains carbon (C) atoms. EDX In compositional analysis, the value of C at the position where Si shows its maximum value is preferably 20 to 55 atoms, and more preferably 30 to 55 atoms. EDX In compositional analysis, the value of C at the position where Si shows the minimum value is preferably 40 atomic% to 90 atomic%, and more preferably 50 atomic% to 80 atomic%.

[0062] EDX In compositional analysis, the value of C at the position where O is at its maximum value is preferably 20 to 55 atoms, and more preferably 30 to 55 atoms. EDX In the compositional analysis, the value of C at the position where O is at its minimum is preferably 40 atomic% to 90 atomic%, and more preferably 50 atomic% to 80 atomic%.

[0063] (Compound modulus of elasticity) The composite elastic modulus of the resin layer in the substrate laminate is not particularly limited, but is, for example, 1 GPa to 20 GPa, preferably 2 GPa to 15 GPa, and more preferably 3 GPa to 10 GPa. For the method of measuring the composite modulus, please refer to the examples described later.

[0064] (Joining strength) In the substrate laminate of the first embodiment, the bonding strength between the first substrate and the second substrate, expressed as surface energy, is preferably 0.2 J / m2 More preferably 1.0 J / m 2 More preferably 2.0 J / m 2 That's all. The surface energy can be determined by the blade insertion test described later.

[0065] (Void) In the substrate laminate of the first embodiment, it is preferable that voids are less likely to occur at the bonding surface between the resin layer and the substrate even when heated to 400°C. The ratio of the total area of ​​voids (void area ratio) when heated to 400°C is preferably 30% or less, more preferably 20% or less, and even more preferably 10% or less. The void area ratio is calculated by dividing the total area of ​​voids by the total area over which transmitted light could be observed, and then multiplying by 100, in infrared light transmission observation. If infrared light transmission observation is difficult, the results can be obtained using the same method with reflected waves from an ultrasonic microscope, transmitted waves from an ultrasonic microscope, or infrared reflected light, preferably with reflected waves from an ultrasonic microscope.

[0066] <Electrode> The substrate laminate of the first embodiment may further include an electrode penetrating the resin layer between the first substrate and the second substrate. This electrode allows the first substrate and the second substrate to be electrically connected. Examples of electrodes include electrodes containing at least one metal selected from the group consisting of Cu, gold, and tin.

[0067] Figure 1 is a schematic cross-sectional view conceptually showing an example of a substrate laminate that includes electrodes. As shown in Figure 1, the substrate laminate 100 according to this example includes a first substrate 11, a resin layer 31, and a second substrate 21 in this order, and further includes an electrode 32 penetrating the resin layer 31 between the first substrate 11 and the second substrate 21.

[0068] In the substrate laminate 100, the first substrate 11 and the second substrate 21 may each include a substrate body (e.g., a Si substrate body) and an inorganic layer (e.g., an SiO2 layer). In this case, the inorganic layer may be placed between at least one of the substrate bodies and the resin layer 31.

[0069] Furthermore, in the substrate laminate 100, the resin layer 31 and the electrode 32 may each be formed by laminating multiple layers. In this case, the structure of the resin layer 31 and the electrode 32 may be a laminated structure in which multiple layers are stacked, or a single-layer structure formed by stacking and then fusing multiple layers. A substrate laminate in which the resin layer 31 and the electrode 32 are each formed by stacking multiple layers can be manufactured by hybrid bonding. Here, hybrid bonding refers to a type of bonding in which electrodes are joined together and insulating layers are joined together by bringing two surfaces with exposed electrodes and insulating layers into contact with each other. Hybrid connections offer an advantage in terms of reducing the pitch of wiring spacing.

[0070] [Laminated substrate (second embodiment)] The substrate laminate of the second embodiment is the same as the substrate laminate of the first embodiment, except that it has the characteristic of having an O ratio of 1.3 or more as of the first embodiment, and may or may not have the characteristic of having a Si ratio of 1.5 or more as of the first embodiment, and the preferred embodiments are also the same.

[0071] [Specific examples of compositions for forming a resin layer] Hereinafter, we will describe specific examples of compositions (e.g., coating liquids) for forming the resin layer in this disclosure, namely Composition A and Composition B. For compositions for forming the resin layer, you may refer to prior art such as International Publication No. 2018 / 199117, International Publication No. 2022 / 054839, and Japanese Patent Publication No. 2021-182621.

[0072] <Composition A> Composition A is, A compound (A) having a cationic functional group containing at least one primary nitrogen atom and a secondary nitrogen atom, a siloxane bond (Si-O bond), and an amino group, with a weight-average molecular weight of 130 to 10000, The composition comprises compound (B), which has three or more -C(=O)OX groups (where X is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms) in its molecule, and of the three or more -C(=O)OX groups, one to six are -C(=O)OH groups, and has a weight-average molecular weight of 200 to 600.

[0073] Composition A, by containing compound (A) and compound (B), can form a resin layer of uniform thickness (i.e., the resin layer in this disclosure; the same applies hereinafter) and also exhibits excellent bonding strength between substrates. Furthermore, since it exhibits excellent bonding strength between substrates even when the thickness of the resin layer is reduced, it is advantageous when forming a multilayer three-dimensional structure while miniaturizing. In addition, because the thickness of the resin layer can be reduced, the solvent is easily evaporated when manufacturing the substrate laminate, and the generation of voids is suppressed. Furthermore, because the generation of voids is suppressed, the bonding area does not tend to decrease, and unintended delamination of the substrate can be suppressed.

[0074] (Compound (A)) Compound (A) is a compound having a weight-average molecular weight of 130 to 10000, and having a cationic functional group containing at least one primary nitrogen atom and a secondary nitrogen atom, a siloxane bond (Si-O bond), and an amino group. The cationic functional group is not particularly limited as long as it can carry a positive charge and contains at least one primary nitrogen atom and a secondary nitrogen atom.

[0075] Furthermore, compound (A) may contain tertiary nitrogen atoms in addition to primary and secondary nitrogen atoms.

[0076] As used herein, the "primary nitrogen atom" refers to a nitrogen atom bonded to only two hydrogen atoms and one atom other than a hydrogen atom (e.g., the nitrogen atom contained in a primary amino group (-NH2 group)), or a nitrogen atom (cation) bonded to only three hydrogen atoms and one atom other than a hydrogen atom. Also, the "secondary nitrogen atom" refers to a nitrogen atom bonded to only one hydrogen atom and two atoms other than a hydrogen atom (i.e., the nitrogen atom contained in the functional group represented by the following formula (a)), or a nitrogen atom (cation) bonded to only two hydrogen atoms and two atoms other than a hydrogen atom. Also, the "tertiary nitrogen atom" refers to a nitrogen atom bonded to only three atoms other than a hydrogen atom (i.e., the nitrogen atom in the functional group represented by the following formula (b)), or a nitrogen atom (cation) bonded to only one hydrogen atom and three atoms other than a hydrogen atom.

[0077]

Chemical formula

[0078] In formula (a) and formula (b), * indicates the bonding position with an atom other than a hydrogen atom. Here, the functional group represented by the formula (a) may be a functional group constituting a part of a secondary amino group (-NHR a group; where R a represents an alkyl group), or may be a divalent linking group contained in the polymer backbone. Also, the functional group represented by the formula (b) (i.e., the tertiary nitrogen atom) may be a functional group constituting a part of a tertiary amino group (-NR b R c group; where R b and R c each independently represent an alkyl group), or may be a trivalent linking group contained in the polymer backbone.

[0079] The weight average molecular weight of compound (A) is 130 or more and 10000 or less, more preferably 130 or more and 5000 or less, and even more preferably 130 or more and 2000 or less.

[0080] In this specification, weight-average molecular weight refers to the weight-average molecular weight in terms of polyethylene glycol, measured by the GPC (Gel Permeation Chromatography) method. Specifically, the weight-average molecular weight was determined using an aqueous solution of sodium nitrate with a concentration of 0.1 mol / L as the developing solvent, and the refractive index was measured using a Shodex DET RI-101 analyzer and two types of analytical columns (TSKgel G6000PWXL-CP and TSKgel G3000PWXL-CP manufactured by Tosoh) at a flow rate of 1.0 mL / min. The substance is detected and analyzed using polyethylene glycol / polyethylene oxide as a standard, with calculations performed using analysis software (Waters Empower3).

[0081] Furthermore, compound (A) may optionally have anionic functional groups, nonionic functional groups, etc. The nonionic functional group may be either a hydrogen bond acceptor or a hydrogen bond donor. Examples of the nonionic functional group include a hydroxyl group, a carbonyl group, an ether group (-O-), and the like. The anionic functional group is not particularly limited as long as it is a functional group capable of carrying a negative charge. Examples of the anionic functional group include carboxylic acid groups, sulfonic acid groups, and sulfate groups.

[0082] Examples of compound (A) include siloxanediamines, silane coupling agents having an amino group, and siloxane polymers of silane coupling agents having an amino group. Examples of silane coupling agents containing an amino group include compounds represented by the following formula (A-3).

[0083] [ka]

[0084] In formula (A-3), R 1R represents an alkyl group having 1 to 4 carbon atoms, which may be substituted. 2 and R 3 Each of these independently represents an alkylene group, ether group, or carbonyl group having 1 to 12 carbon atoms, which may be substituted (the skeleton may contain carbonyl groups, ether groups, etc.). 4 and R 5 Each of these independently represents an alkylene group or single bond having 1 to 4 carbon atoms, which may be substituted. Ar represents a divalent or trivalent aromatic ring. X 1 X represents hydrogen or an alkyl group having 1 to 5 carbon atoms, which may be substituted. 2 R represents hydrogen, a cycloalkyl group, a heterocyclic group, an aryl group, or a C1-C5 alkyl group which may be substituted (may contain a carbonyl group, ether group, etc. in its skeleton). 1 , R 2 , R 3 , R 4 , R 5 , X 1 They may be the same or different. R 1 , R 2 , R 3 , R 4 , R 5 , X 1 , X 2 Examples of substituents on the alkyl group and alkylene group in the compound include, independently, amino groups, hydroxyl groups, alkoxy groups, cyano groups, carboxylic acid groups, sulfonic acid groups, halogens, and the like. Examples of divalent or trivalent aromatic rings in Ar include divalent or trivalent benzene rings. 2 Examples of aryl groups in this context include phenyl groups, methylbenzyl groups, and vinylbenzyl groups.

[0085] Specific examples of silane coupling agents represented by formula (A-3) include, for example, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminoisobutyldimethylmethoxysilane, N-(2-aminoethyl)-3-aminoisobutylmethyldimethoxysilane, N-(2-aminoethyl)-11-aminoundecyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, (aminoethylaminoethyl)phenyltriethoxysilane, methylbenzylaminoethylaminopropyltrimethoxysilane, benzylaminoethylaminopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, (aminoethylaminoethyl)phenyltriethoxysilane, Examples include (Tylaminoethyl)phenethyltrimethoxysilane, (aminoethylaminomethyl)phenethyltrimethoxysilane, N-[2-[3-(trimethoxysilyl)propylamino]ethyl]ethylenediamine, 3-aminopropyldiethoxymethylsilane, 3-aminopropyldimethoxymethylsilane, 3-aminopropyldimethylethoxysilane, 3-aminopropyldimethylmethoxysilane, trimethoxy[2-(2-aminoethyl)-3-aminopropyl]silane, diaminomethylmethyldiethoxysilane, methylaminomethylmethyldiethoxysilane, p-aminophenyltrimethoxysilane, N-methylaminopropyltriethoxysilane, N-methylaminopropylmethyldiethoxysilane, (phenylaminomethyl)methyldiethoxysilane, acetamidopropyltrimethoxysilane, and hydrolysates thereof.

[0086] Examples of silane coupling agents containing amino groups other than formula (A-3) include N,N-bis[3-(trimethoxysilyl)propyl]ethylenediamine, N,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine, bis[(3-triethoxysilyl)propyl]amine, piperazinylpropylmethyldimethoxysilane, bis[3-(triethoxysilyl)propyl]urea, bis(methyldiethoxysilylpropyl)amine, 2 Examples include 2-dimethoxy-1,6-diaza-2-silacyclooctane, 3,5-diamino-N-(4-(methoxydimethylsilyl)phenyl)benzamide, 3,5-diamino-N-(4-(triethoxysilyl)phenyl)benzamide, 5-(ethoxydimethylsilyl)benzene-1,3-diamine, and hydrolysates thereof.

[0087] The aforementioned silane coupling agents having amino groups may be used individually or in combination of two or more. Furthermore, a silane coupling agent having amino groups may be used in combination with a silane coupling agent without amino groups. For example, a silane coupling agent having mercapto groups may be used to improve adhesion to metals.

[0088] Alternatively, polymers formed via siloxane bonds (Si-O-Si) from these silane coupling agents (siloxane polymers) may be used. For example, from the hydrolysis product of 3-aminopropyltrimethoxysilane, polymers having a linear siloxane structure, a branched siloxane structure, a cyclic siloxane structure, a cage-like siloxane structure, and the like can be obtained. The cage-like siloxane structure can be represented, for example, by the following formula (A-1).

[0089] [ka]

[0090] Examples of siloxanediamines include compounds represented by the following formula (A-2). In formula (A-2), i is an integer from 0 to 4, j is an integer from 1 to 3, and Me is a methyl group.

[0091] [ka]

[0092] Examples of siloxanediamines include 1,3-bis(3-aminopropyl)tetramethyldisiloxane (in formula (A-2), i=0, j=1) and 1,3-bis(2-aminoethylamino)propyltetramethyldisiloxane (in formula (A-2), i=1, j=1).

[0093] Since compound (A) has primary or secondary amino groups, it can strongly bond the substrates together through electrostatic interactions with functional groups such as hydroxyl groups, epoxy groups, carboxyl groups, amino groups, and mercapto groups that may be present on the surfaces of the first and second substrates, or by forming dense covalent bonds with such functional groups. Furthermore, since compound (A) has a primary or secondary amino group, it readily dissolves in the polar solvent (D) described later. By using compound (A), which readily dissolves in the polar solvent (D), the affinity with the hydrophilic surface of the substrate, such as a silicon substrate, is increased, making it easier to form a smooth film and allowing the resin layer to be made thinner.

[0094] As compound (A), compounds having a Si-O bond and a primary amino group are preferred from the viewpoint of forming a thermal crosslinking structure such as an amide, amide-imide, or imide to further improve heat resistance.

[0095] A ratio of the total number of primary and secondary nitrogen atoms in compound (A) to the number of silicon atoms (total number of primary and secondary nitrogen atoms / number of silicon atoms) of 0.2 or more and 5 or less is preferable from the viewpoint of forming a smooth thin film.

[0096] For compound (A), from the standpoint of adhesion between substrates, it is preferable that the molar ratio of Si elements to non-crosslinking groups such as methyl groups bonded to Si elements satisfies the relationship (non-crosslinking groups) / Si < 2. By satisfying this relationship, the crosslinking density of the formed film (crosslinking between Si-O-Si bonds and amide bonds, imide bonds, etc.) is improved, resulting in sufficient adhesion between substrates and suppression of substrate delamination.

[0097] As described above, compound (A) has a cationic functional group containing at least one primary nitrogen atom and a secondary nitrogen atom. Here, if compound (A) contains a primary nitrogen atom, it is preferable that the proportion of primary nitrogen atoms to the total nitrogen atoms in compound (A) is 20 mol% or more, more preferably 25 mol% or more, and even more preferably 30 mol% or more. Furthermore, compound (A) may have a cationic functional group that contains a primary nitrogen atom but does not contain nitrogen atoms other than primary nitrogen atoms (e.g., secondary nitrogen atoms, tertiary nitrogen atoms).

[0098] Furthermore, if compound (A) contains secondary nitrogen atoms, it is preferable that the proportion of secondary nitrogen atoms in compound (A) is 5 mol% or more and 50 mol% or less, and more preferably 10 mol% or more and 45 mol% or less.

[0099] Furthermore, compound (A) may contain tertiary nitrogen atoms in addition to primary and secondary nitrogen atoms. If compound (A) contains tertiary nitrogen atoms, it is preferable that the proportion of tertiary nitrogen atoms to the total nitrogen atoms in compound (A) is 20 mol% or more and 50 mol% or less, and more preferably 25 mol% or more and 45 mol% or less.

[0100] In this embodiment, the content of the component derived from compound (A) in the resin layer is not particularly limited, and can be, for example, 1% by mass or more and 82% by mass or less of the total resin layer, preferably 5% by mass or more and 82% by mass or less, and more preferably 13% by mass or more and 82% by mass or less.

[0101] (Compound (B)) Compound (B) is a compound having three or more -C(=O)OX groups (where X is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms) in its molecule, with one to six of the three or more -C(=O)OX groups (hereinafter also referred to as "COOX") being -C(=O)OH groups (hereinafter also referred to as "COOH"), and having a weight-average molecular weight of 200 to 600.

[0102] Compound (B) is a compound having three or more -C(=O)OX groups (where X is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms) in its molecule, preferably a compound having three to six -C(=O)OX groups in its molecule, and more preferably a compound having three or four -C(=O)OX groups in its molecule.

[0103] In compound (B), X in the -C(=O)OX group can be a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, with hydrogen atoms, methyl groups, ethyl groups, and propyl groups being preferred. The X in the -C(=O)OX group may be the same or different from each other.

[0104] Compound (B) is a compound having one to six -C(=O)OH groups in its molecule where X is a hydrogen atom, preferably a compound having one to four -C(=O)OH groups in its molecule, more preferably a compound having two to four -C(=O)OH groups in its molecule, and even more preferably a compound having two or three -C(=O)OH groups in its molecule.

[0105] Compound (B) is a compound with a weight-average molecular weight of 200 to 600. Preferably, it is a compound with a weight-average molecular weight of 200 to 400.

[0106] Compound (B) preferably has a ring structure within its molecule. Examples of ring structures include alicyclic structures and aromatic ring structures. Compound (B) may also have multiple ring structures within its molecule, and these multiple ring structures may be the same or different.

[0107] Examples of alicyclic structures include alicyclic structures having 3 to 8 carbon atoms, preferably alicyclic structures having 4 to 6 carbon atoms, and the ring structure may be saturated or unsaturated. More specifically, examples of alicyclic structures include saturated alicyclic structures such as cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, cycloheptane rings, and cyclooctane rings; and unsaturated alicyclic structures such as cyclopropene rings, cyclobutene rings, cyclopentene rings, cyclohexene rings, cycloheptene rings, and cyclooctene rings.

[0108] The aromatic ring structure is not particularly limited as long as it is an aromatic ring structure, and examples include benzene-based aromatic rings such as benzene rings, naphthalene rings, anthracene rings, and perylene rings; aromatic heterocycles such as pyridine rings and thiophene rings; and non-benzene-based aromatic rings such as indene rings and azulene rings.

[0109] The ring structure that compound (B) has within the molecule is preferably at least one selected from the group consisting of a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a benzene ring, and a naphthalene ring, and at least one of the benzene ring and the naphthalene ring is more preferred from the viewpoint of further improving the heat resistance of the resin layer.

[0110] As mentioned above, compound (B) may have multiple ring structures within its molecule, and if the ring structure is benzene, it may have a biphenyl structure, a benzophenone structure, a diphenyl ether structure, and the like.

[0111] The preferred ring structure of compound (B) within the molecule is one having two or more -C(=O)OX groups.

[0112] Compound (B) preferably has fluorine atoms in its molecule, more preferably has one to six fluorine atoms in its molecule, and even more preferably has three to six fluorine atoms in its molecule. For example, compound (B) may have a fluoroalkyl group in its molecule, specifically a trifluoroalkyl group or a hexafluoroisopropyl group.

[0113] Furthermore, compound (B) can be a carboxylic acid compound such as alicyclic carboxylic acid, benzenecarboxylic acid, naphthalenecarboxylic acid, diphthalic acid, or fluorinated aromatic carboxylic acid; or a carboxylic acid ester compound such as alicyclic carboxylic acid ester, benzenecarboxylic acid ester, naphthalenecarboxylic acid ester, diphthalic acid ester, or fluorinated aromatic carboxylic acid ester. Note that a carboxylic acid ester compound is a compound that has a carboxyl group (-C(=O)OH group) in its molecule, and in three or more -C(=O)OX groups, at least one X is an alkyl group having 1 to 6 carbon atoms (i.e., having an ester bond). In this embodiment, because compound (B) is a carboxylic acid ester compound, aggregation due to association between compound (A) and compound (B) is suppressed, resulting in fewer aggregates and pits, and making it easier to adjust the film thickness.

[0114] The carboxylic acid compound is preferably a tetravalent or less carboxylic acid compound containing four or fewer -C(=O)OH groups, and more preferably a trivalent or tetravalent carboxylic acid compound containing three or four -C(=O)OH groups.

[0115] The carboxylic acid ester compound is preferably a compound that contains three or fewer carboxyl groups (-C(=O)OH groups) and three or fewer ester bonds in its molecule, and more preferably a compound that contains two or fewer carboxyl groups and two or fewer ester bonds in its molecule.

[0116] Furthermore, in the carboxylic acid ester compound, if X is an alkyl group having 1 to 6 carbon atoms in three or more -C(=O)OX groups, X is preferably a methyl group, ethyl group, propyl group, butyl group, etc., but it is preferable that X be an ethyl group or a propyl group in order to further suppress aggregation due to association between compound (A) and compound (B).

[0117] Specific examples of the carboxylic acid compounds mentioned above are not limited to these, but include alicyclic carboxylic acids such as 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, and 1,2,3,4,5,6-cyclohexanehexacarboxylic acid; benzenecarboxylic acids such as 1,2,4-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, pyromellitic acid, benzenepentacarboxylic acid, and mellitic acid; and 1,4,5,8-naphthalenetetracarboxylic acid. Naphthalene carboxylic acids such as naphthalene acid, 2,3,6,7-naphthalenetetracarboxylic acid; 3,3',5,5'-tetracarboxydiphenylmethane, biphenyl-3,3',5,5'-tetracarboxylic acid, biphenyl-3,4',5-tricarboxylic acid, biphenyl-3,3',4,4'-tetracarboxylic acid, benzophenone-3,3',4,4'-tetracarboxylic acid, 4,4'-oxydiphthalic acid, 3,4'-oxydiphthalic acid, 1,3-bis(phthalic acid)tetramethyldisiloxane, 4,4'-(ethyn-1,2-diyl)diphthalic acid, 4,4'-(1,4-phenylenebis(oxy))diphthalic acid (4,4'-(1,4-phenylenebis(oxy))diphthalic acid), 4,4'-([1,1'-biphenyl]-4,4'-diylbis(oxy))diphthalic acid, 4,4'-((oxybis(4,1-phenylene))bis(oxy))diphthalic acid, etc. Examples include diphthalic acid; perylene carboxylic acids such as perylene-3,4,9,10-tetracarboxylic acid; anthracene carboxylic acids such as anthracene-2,3,6,7-tetracarboxylic acid; and fluorinated aromatic ring carboxylic acids such as 4,4'-(hexafluoroisopropylidene)diphthalic acid, 9,9-bis(trifluoromethyl)-9H-xanthene-2,3,6,7-tetracarboxylic acid, and 1,4-ditrifluoromethylpyromellitic acid.

[0118] Specific examples of the carboxylic acid ester compounds include compounds in which at least one carboxyl group in the above-mentioned specific examples of carboxylic acid compounds is substituted with an ester group. Examples of carboxylic acid ester compounds include half-esterified compounds represented by the following general formulas (B-1) to (B-6).

[0119] [ka]

[0120] In general formulas (B-1) to (B-6), R is independently an alkyl group having 1 to 6 carbon atoms, with methyl, ethyl, propyl, and butyl groups being preferred, and ethyl and propyl groups being more preferred.

[0121] Half-esterified compounds can be produced, for example, by mixing a carboxylic acid anhydride (the anhydride of the aforementioned carboxylic acid compound) with an alcohol solvent and opening the ring of the carboxylic acid anhydride.

[0122] In this embodiment, the content of components derived from compound (B) in the resin layer is not particularly limited. For example, the ratio of the number of carbonyl groups (-(C=O)-Y) in the substance derived from compound (B) to the total number of nitrogen atoms in the substance derived from compound (A) ((-(C=O)-Y) / N) is preferably 0.1 to 3.0, more preferably 0.3 to 2.5, and even more preferably 0.4 to 2.2. Here, in -(C=O)-Y, Y represents an imide-crosslinked or amide-crosslinked nitrogen atom, OH, or ester group. By having (-(C=O)-Y) / N be 0.1 to 3.0, the resin layer preferably has a thermally crosslinked structure such as amide, amide-imide, or imide, and exhibits superior heat resistance.

[0123] Since compound (A) has uncrosslinked cationic functional groups, if the resin layer contains compound (A) but does not contain compound (B), the crosslinking density may be low and the heat resistance may be insufficient. On the other hand, in the resin layer, the cationic functional groups of compound (A) and the carboxyl groups of compound (B) react to form covalent bonds, resulting in a high crosslinking density and high heat resistance.

[0124] (Compound (C)) Composition A may further contain the following compound (C). Compound (C) is a compound having a ring structure and one or more primary nitrogen atoms directly bonded to the ring structure. Compound (C) reacts with compound (B) together with compound (A) to form a hardened product. Compound (C) has a ring structure and one or more primary nitrogen atoms directly bonded to the ring structure. It is believed that the introduction of this structure into the cured product increases the rigidity of the cured product and reduces its coefficient of thermal expansion. Compound (C) may be used alone or in combination of two or more types.

[0125] In this disclosure, "primary nitrogen atom directly bonded to a ring structure" means a primary nitrogen atom (-NH2) that is bonded to a ring structure by a single bond (i.e., without the involvement of carbon atoms, etc.).

[0126] The number of primary nitrogen atoms directly bonded to the ring structure of compound (C) within the molecule is not particularly limited, as long as there is one or more. From the viewpoint of increasing the crosslinking density, it is preferable that there be two or more, and more preferably a diamine compound having two primary amino groups or a triamine compound having three primary amino groups.

[0127] Compound (C) may have one ring structure or multiple ring structures within its molecule. If compound (C) has multiple ring structures within its molecule, it may have a cationic functional group containing a primary nitrogen atom directly bonded to each ring structure, or it may have a cationic functional group containing a primary nitrogen atom directly bonded to only one of the ring structures.

[0128] If compound (C) has multiple ring structures within its molecule, these ring structures may be the same or different, and may form a fused ring. Alternatively, the multiple ring structures may be linked by single bonds, or they may be linked via linking groups such as ether groups, carbonyl groups, sulfonyl groups, or methylene groups.

[0129] Examples of ring structures included in compound (C) include alicyclic structures, aromatic rings (including heterocyclic structures), and fused ring structures of these. Examples of alicyclic structures include those having 3 to 8 carbon atoms, preferably 4 to 6 carbon atoms. The ring structure may be saturated or unsaturated. More specifically, examples include saturated alicyclic structures such as cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, cycloheptane rings, and cyclooctane rings; and unsaturated alicyclic structures such as cyclopropene rings, cyclobutene rings, cyclopentene rings, cyclohexene rings, cycloheptene rings, and cyclooctene rings.

[0130] Examples of aromatic ring structures include those with 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms. Specifically, examples include benzene-based aromatic ring structures such as benzene rings, naphthalene rings, anthracene rings, and perylene rings, and non-benzene-based aromatic ring structures such as pyridine rings, thiophene rings, indene rings, and azulene rings.

[0131] Examples of heterocyclic structures include three-membered to ten-membered rings, preferably five-membered or six-membered rings. Examples of heteroatoms included in the heterocyclic ring include sulfur atoms, nitrogen atoms, and oxygen atoms, and one or more of these may be present. Examples of heterocyclic structures include oxazole rings, thiophene rings, pyrrole rings, pyrrolidine rings, pyrazole rings, imidazole rings, triazole rings, isocyanuric rings, pyridine rings, pyridazine rings, pyrimidine rings, pyrazine rings, piperidine rings, piperazine rings, triazine rings, indole rings, indoline rings, quinoline rings, acridine rings, naphthyridine rings, quinazoline rings, purine rings, and quinoxaline rings.

[0132] The ring structure that compound (C) has within the molecule is more preferably a benzene ring, a cyclohexane ring, or a benzoxazole ring.

[0133] The ring structure of compound (C) within the molecule may have substituents other than a primary nitrogen atom. For example, it may have an alkyl group having 1 to 6 carbon atoms, an alkyl group substituted with a halogen atom, and so on.

[0134] The weight-average molecular weight of compound (C) is not particularly limited. For example, it may be between 80 and 600, between 90 and 500, or between 100 and 450.

[0135] Examples of compound (C) include alicyclic amines, aromatic amines, heterocyclic amines having a nitrogen-containing heterocyclic ring, and amine compounds having both heterocyclic and aromatic rings. Examples of alicyclic amines include cyclohexylamine and dimethylaminocyclohexane. Specific examples of aromatic ring amines include diaminodiphenyl ether, xylenediamine (preferably paraxylenediamine), diaminobenzene, diaminotoluene, methylenedianiline, dimethyldiaminobiphenyl, bis(trifluoromethyl)diaminobiphenyl, diaminobenzophenone, diaminobenzanilide, bis(aminophenyl)fluorene, bis(aminophenoxy)benzene, bis(aminophenoxy)biphenyl, dicarboxydiaminodiphenylmethane, diaminoresorcinol, dihydroxybenzidine, diaminobenzidine, 1,3,5-triaminophenoxybenzene, 2,2'-dimethylbenzidine, and tris(4-aminophenyl)amine. Examples of heterocyclic amines containing nitrogen include melamine, ammeline, melam, melem, and tris(4-aminophenyl)amine. Examples of amine compounds that have both heterocyclic and aromatic rings include N2,N4,N6-tris(4-aminophenyl)-1,3,5-triazine-2,4,6-triamine and 2-(4-aminophenyl)benzoxazole-5-amine.

[0136] The amount of compound (C) in composition A is not particularly limited, as long as the proportion of primary nitrogen atoms in compound (A) to the total of primary and secondary nitrogen atoms in compound (A) and primary nitrogen atoms in compound (C) is between 3 mol% and 95 mol%. From the viewpoint of balancing thermal expansion coefficient and bonding strength, the above ratio is preferably 5 mol% to 75 mol%, more preferably 10 mol% to 50 mol%, and even more preferably 10 mol% to 30 mol%.

[0137] (Polar solvent) Composition A may contain a polar solvent. In this disclosure, "polar solvent" refers to a solvent having a dielectric constant of 5 or more at room temperature (25°C). When composition A contains a polar solvent, the solubility of each component in composition A is improved. Polar solvents may be used individually or in combination of two or more.

[0138] Polar solvents specifically include protic solvents such as water and heavy water; alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutyl alcohol, isopentyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 2-methoxyethanol, 2-ethoxyethanol, benzyl alcohol, diethylene glycol, triethylene glycol, and glycerin; ethers such as tetrahydrofuran and dimethoxyethane; aldehydes and ketones such as furfural, acetone, ethyl methyl ketone, and cyclohexanone; acid derivatives such as acetic anhydride, ethyl acetate, butyl acetate, ethylene carbonate, propylene carbonate, formaldehyde, N-methylformamide, N,N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and hexamethylphosphate; nitriles such as acetonitrile and propionitrile; and nitro compounds such as nitromethane and nitrobenzene; and sulfur compounds such as dimethyl sulfoxide. The polar solvent preferably contains a protic solvent, more preferably water, and even more preferably ultrapure water.

[0139] If composition A contains a polar solvent, its content is not particularly limited. For example, it may be 1.0% by mass or more and 99.99896% by mass or 40% by mass or more and 99.99896% by mass relative to the entire composition A.

[0140] (Additives) Composition A may contain additives as needed. Examples of additives include acids having a carboxyl group with a weight-average molecular weight of 46 to 195, and bases having a nitrogen atom and a weight-average molecular weight of 17 to 120, which do not have a ring structure.

[0141] It is presumed that because composition A contains an acid with a weight-average molecular weight of 46 to 195 that has a carboxyl group, the primary or secondary nitrogen atoms of compounds (A) and (C) form ionic bonds with the carboxyl group in the acid, thereby suppressing aggregation due to association between compounds (A) and (C) and compound (B). More specifically, it is presumed that aggregation is suppressed because the interaction (e.g., electrostatic interaction) between the ammonium ions derived from compounds (A) and (C) and the carboxylate ions derived from the carboxyl group in the acid is stronger than the interaction between the ammonium ions derived from compounds (A) and (C) and the carboxylate ions derived from the carboxyl group in compound (B). However, the present invention is not limited in any way by the above presumption.

[0142] The types of acids with a carboxyl group and a weight-average molecular weight of 46 to 195 are not particularly limited, and include monocarboxylic acid compounds, dicarboxylic acid compounds, and oxydicarboxylic acid compounds. More specifically, examples include formic acid, acetic acid, malonic acid, oxalic acid, benzoic acid, lactic acid, glycolic acid, glyceric acid, butyric acid, methoxyacetic acid, ethoxyacetic acid, phthalic acid, terephthalic acid, picolinic acid, salicylic acid, and 3,4,5-trihydroxybenzoic acid (excluding those that fall under compound (B)).

[0143] When composition A contains an acid with a weight-average molecular weight of 46 to 195, the amount is not particularly limited, but for example, it is preferable that the ratio of the number of carboxyl groups of the acid to the total number of primary and secondary nitrogen atoms of compound (A) and compound (C) (COOH / N) is 0.01 to 10, more preferably 0.02 to 6, and even more preferably 0.5 to 3.

[0144] It is presumed that the aggregation of compounds (A) and (C) with compound (B) is suppressed because composition A contains a base with a weight-average molecular weight of 17 to 120 having a nitrogen atom, causing an ionic bond to form between the carboxyl group of compound (B) and the amino group of the base. More specifically, it is presumed that aggregation is suppressed because the interaction between the carboxylate ion derived from the carboxyl group in compound (B) and the ammonium ion derived from the amino group in the base is stronger than the interaction between the ammonium ions derived from compounds (A) and (C) and the carboxylate ion derived from the carboxyl group in compound (B). However, the present invention is not limited in any way by the above presumption.

[0145] The types of compounds containing a nitrogen atom and having a weight-average molecular weight of 17 to 120 are not particularly limited, and include monoamine compounds, diamine compounds, etc. (except for those falling under compound (A) and compound (C)). More specifically, examples include ammonia, ethylamine, ethanolamine, diethylamine, triethylamine, ethylenediamine, N-acetylethylenediamine, N-(2-aminoethyl)ethanolamine, N-(2-aminoethyl)glycine, etc.

[0146] When composition A contains a base with a weight-average molecular weight of 17 or more and 120 or less, the amount is not particularly limited, but for example, the ratio of the number of nitrogen atoms in the base to the number of carboxyl groups in compound (B) (N / COOH) is preferably 0.5 or more and 5 or less, and more preferably 0.9 or more and 3 or less.

[0147] (Other ingredients) When selectivity for plasma etching resistance is required for composition A (for example, when used as a gap fill material or embedded insulating film), it may contain a metal alkoxide represented by the following general formula (I). R1 n M(OR2) m-n ...(I) (In the formula, R1 is a non-hydrolyzable group, R2 is an alkyl group having 1 to 6 carbon atoms, M represents at least one metal atom selected from the group of metal atoms Ti, Al, Zr, Sr, Ba, Zn, B, Ga, Y, Ge, Pb, P, Sb, V, Ta, W, La, Nd, and In, m is the valence of the metal atom M, which is 3 or 4, n is an integer from 0 to 2 if m is 4, and 0 or 1 if m is 3, if there are multiple R1s, each R1 may be the same or different from one another, and if there are multiple OR2s, each OR2 may be the same or different from one another.)

[0148] When the film produced from composition A is required to have insulating properties (for example, for use as an insulating film for silicon through-vias or for use as an embedded insulating film), a silane compound (excluding those corresponding to compound (A)) may be included to improve insulating properties or mechanical strength. Specific examples of silane compounds include tetraethoxysilane, tetramethoxysilane, bistriethoxysilylethane, bistriethoxysilylmethane, bis(methyldiethoxysilyl)ethane, 1,1,3,3,5,5-hexaethoxy-1,3,5-trisilacyclohexane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahydroxylcyclosiloxane, 1,1,4,4-tetramethyl-1,4-diethoxydisylethylene, 1,3,5-trimethyl-1,3,5-trimethyl-1,3,5-triethoxy-1,3,5-trisilacyclohexane, and silane coupling agents having functional groups other than amino groups (epoxy groups, mercapto groups, etc.).

[0149] Composition A may contain solvents other than polar solvents. Examples of solvents other than polar solvents include n-hexane.

[0150] Composition A may contain, for example, benzotriazole or a derivative thereof to suppress copper corrosion.

[0151] The pH of composition A is not particularly limited, but it is preferably between 2.0 and 12.0. When the pH of composition A is between 2.0 and 12.0, damage to the substrate by composition A is suppressed. Composition A preferably contains sodium and potassium at a concentration of 10 ppb by mass or less on an elemental basis. If the sodium or potassium content is 10 ppb by mass or less on an elemental basis, it is possible to suppress problems with the electrical characteristics of the semiconductor device, such as transistor malfunctions.

[0152] If composition A contains components other than compound (A), compound (B), and compound (C), the total mass of compound (A), compound (B), and compound (C) is preferably 50% by mass or more, more preferably 70% by mass or more, and more preferably 80% by mass or more, of the total mass of nonvolatile components in composition A. In this disclosure, "nonvolatile components" refers to components other than those removed when composition A becomes a cured product (such as solvents).

[0153] <Composition B> Composition B comprises at least one of the following compounds: (X1) having a structure represented by the following general formula (1) and a molecular weight of 400 to 5000, and (X2) having a structure represented by the following general formula (2) and a molecular weight of 400 to 5000.

[0154] [ka]

[0155] In general formula (1), R1 and R3 are each independently organic groups having 6 or fewer carbon atoms, R2 is a methylene group, an ethylene group, a propylene group, or a phenylene group, a is 2 or 3, b is the number of 3-a, and X1 is a structure derived from a carboxylic acid dianhydride.

[0156] [ka]

[0157] In general formula (2), R1 and R3 are each independently organic groups having 6 or fewer carbon atoms, R2 is a methylene group, an ethylene group, a propylene group, or a phenylene group, a is 2 or 3, b is the number of 3-a, X1 is a structure derived from a carboxylic acid dianhydride, X2 is a structure derived from an amine compound, and n is a positive number.

[0158] According to composition B, a resin layer with less residual stress can be formed compared to composition B in which the precursors of compound (X1) or compound (X2), such as a silane coupling agent, a carboxylic acid dianhydride, or an amine compound, are present in an unreacted state. The reason for this is not entirely clear, but for example, it is thought that because the precursors of compound (X1) or compound (X2) are reacted before composition B is applied to the substrate, the curing shrinkage of the resin layer associated with the reaction is suppressed, and the residual stress of the resin layer is reduced, compared to when these precursors are reacted on the substrate to form the resin layer.

[0159] In general formula (1), X1 is a structure derived from a carboxylic acid dianhydride, and preferably includes a ring structure. Furthermore, the amide group and carboxyl group bonded to X1 react on the substrate to form an imide bond. As a result, the resulting resin layer exhibits excellent heat resistance.

[0160] In general formula (1), it is preferable that a is 2. In general formula (1), R1 and R3 represent organic groups having 6 or fewer carbon atoms, and preferably alkyl groups having 6 or fewer carbon atoms, more preferably 3 or fewer carbon atoms.

[0161] In general formula (2), X1 and X2 are structures derived from a carboxylic acid dianhydride and an amine compound, respectively, and preferably include a ring structure. Furthermore, the amide group and carboxyl group bonded to X1 react on the substrate to form an imide bond. As a result, the resulting resin layer exhibits excellent heat resistance.

[0162] In general formula (2), it is preferable that a is 2. In general formula (2), R1 and R3 represent an organic group having 6 or fewer carbon atoms, and preferably an alkyl group having 6 or fewer carbon atoms, more preferably 3 or fewer carbon atoms. In general formula (2), n is not particularly restricted as long as it is a positive number, but for example, it may be within the range of 1 to 6. The compound (X2) represented by general formula (2) may be a polyamic acid in which structures derived from carboxylic acid dianhydrides and structures derived from amine compounds are arranged alternately.

[0163] The compound (X1) contained in the above composition B may be a compound having a structure obtained by reacting a silane coupling agent (A) with a carboxylic acid dianhydride (B) having a molecular weight of 200 to 600 and a cyclic structure. The compound (X2) contained in the above composition B may have a structure obtained by reacting a silane coupling agent (A) with a carboxylic acid dianhydride (B) having a molecular weight of 200 to 600 and a cyclic structure, and a structure obtained by reacting an amine compound (C) having a molecular weight of 90 to 600, lacking Si-O bonds and having a cyclic structure, with a carboxylic acid dianhydride (B) having a molecular weight of 200 to 600 and a cyclic structure.

[0164] In this disclosure, carboxylic acid dianhydrides (B) having a molecular weight of 200 to 600 and a cyclic structure, and amine compounds (C) having a molecular weight of 90 to 600, a cyclic structure, and lacking Si-O bonds, may be simply referred to as carboxylic acid dianhydrides (B) and amine compounds (C), respectively.

[0165] (Silane coupling agent (A)) Silane coupling agent (A) is a compound having one or more Si-O bonds in its molecule and reacting with a carboxylic acid dianhydride to produce compound (X1) or compound (X2). The Si-O bonds in silane coupling agent (A) contribute to improving the bonding strength between the resin layer formed using composition B and the substrate.

[0166] The silane coupling agent (A) is not particularly limited as long as it has a functional group that can react with the anhydride group of the carboxylic acid dianhydride (B). Specific examples of functional groups include amino groups, epoxy groups, and isocyanate groups. From the viewpoint of the thermal expansion coefficient of the resin layer and bonding strength, the silane coupling agent (A) preferably has an amino group, and from the viewpoint of forming an imide structure in the resin layer to improve heat resistance, a compound having a primary amino group (-NH2) is more preferable.

[0167] The silane coupling agent (A) may be used alone or in combination of two or more types.

[0168] The molecular weight of the silane coupling agent (A) is not particularly limited. For example, it may be between 130 and 10,000, between 130 and 5,000, or between 130 and 2,000.

[0169] Examples of silane coupling agents (A) having an amino group include compounds represented by the following formula (A-3).

[0170] [ka]

[0171] In formula (A-3), R 1 R represents an alkyl group having 1 to 4 carbon atoms, which may be substituted. 2 and R 3 Each of these independently represents an alkylene group, ether group, or carbonyl group having 1 to 12 carbon atoms, which may be substituted (the skeleton may contain carbonyl groups, ether groups, etc.). 4 and R 5Each independently represents an optionally substituted C1-C4 alkylene group or single bond. Ar represents a divalent or trivalent aromatic ring. X1 represents hydrogen or an optionally substituted C1-C5 alkyl group. X2 represents hydrogen, a cycloalkyl group, a heterocyclic group, an aryl group, or an optionally substituted (may contain carbonyl groups, ether groups, etc.) C1-C5 alkyl group. Multiple R 1 , R 2 , R 3 , R 4 , R 5 , X 1 They may be the same or different. R 1 , R 2 , R 3 , R 4 , R 5 , X 1 , X 2 Examples of substituents on the alkyl group and alkylene group in the compound include, independently, amino groups, hydroxyl groups, alkoxy groups, cyano groups, carboxylic acid groups, sulfonic acid groups, halogens, and the like. Examples of divalent or trivalent aromatic rings in Ar include divalent or trivalent benzene rings. 2 Examples of aryl groups in this context include phenyl groups, methylbenzyl groups, and vinylbenzyl groups.

[0172] Specific examples of silane coupling agents represented by formula (A-3) include, for example, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminoisobutyldimethylmethoxysilane, N-(2-aminoethyl)-3-aminoisobutylmethyldimethoxysilane, N-(2-aminoethyl)-11-aminoundecyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, (aminoethylaminoethyl)phenyltriethoxysilane, methylbenzylaminoethylaminopropyltrimethoxysilane, benzylaminoethylaminopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, Examples include (aminoethylaminoethyl)phenethyltrimethoxysilane, (aminoethylaminomethyl)phenethyltrimethoxysilane, N-[2-[3-(trimethoxysilyl)propylamino]ethyl]ethylenediamine, 3-aminopropyldiethoxymethylsilane, 3-aminopropyldimethoxymethylsilane, 3-aminopropyldimethylethoxysilane, 3-aminopropyldimethylmethoxysilane, trimethoxy[2-(2-aminoethyl)-3-aminopropyl]silane, diaminomethylmethyldiethoxysilane, methylaminomethylmethyldiethoxysilane, p-aminophenyltrimethoxysilane, N-methylaminopropyltriethoxysilane, N-methylaminopropylmethyldiethoxysilane, (phenylaminomethyl)methyldiethoxysilane, and acetamidopropyltrimethoxysilane.

[0173] Examples of silane coupling agents containing amino groups other than formula (A-3) include N,N-bis[3-(trimethoxysilyl)propyl]ethylenediamine, N,N'-bis[3-(trimethoxysilyl)propyl]ethylenediamine, bis[(3-triethoxysilyl)propyl]amine, piperazinylpropylmethyldimethoxysilane, bis[3-(triethoxysilyl)propyl]urea, bis(methyldiethoxysilylpropyl)amine, 2 Examples include 2-dimethoxy-1,6-diaza-2-silacyclooctane, 3,5-diamino-N-(4-(methoxydimethylsilyl)phenyl)benzamide, 3,5-diamino-N-(4-(triethoxysilyl)phenyl)benzamide, and 5-(ethoxydimethylsilyl)benzene-1,3-diamine.

[0174] The silane coupling agent (A) having an amino group may be used alone or in combination of two or more types.

[0175] (Carboxylic acid dianhydride (B)) Carboxylic acid dianhydrides (B) are compounds that have one or more ring structures and two anhydride groups in their molecule, and have a molecular weight of 200 to 600. The molecular weight of the carboxylic acid dianhydride (B) may be between 200 and 400. Carboxylic acid dianhydride (B) may be used alone or in combination of two or more types.

[0176] Examples of ring structures that carboxylic acid dianhydride (B) may have within its molecule include alicyclic structures and aromatic rings (including heterocyclic structures). Carboxylic acid dianhydride (B) may have one ring structure or multiple ring structures within its molecule.

[0177] Examples of alicyclic structures include alicyclic structures having 3 to 8 carbon atoms, preferably alicyclic structures having 4 to 6 carbon atoms, and the ring structure may be saturated or unsaturated. More specifically, examples of alicyclic structures include saturated alicyclic structures such as cyclopropane rings, cyclobutane rings, cyclopentane rings, cyclohexane rings, cycloheptane rings, and cyclooctane rings; and unsaturated alicyclic structures such as cyclopropene rings, cyclobutene rings, cyclopentene rings, cyclohexene rings, cycloheptene rings, and cyclooctene rings.

[0178] The aromatic ring structure is not particularly limited as long as it is an aromatic ring structure, and examples include benzene-based aromatic rings such as benzene rings, naphthalene rings, anthracene rings, and perylene rings; aromatic heterocycles such as pyridine rings and thiophene rings; and non-benzene-based aromatic rings such as indene rings and azulene rings.

[0179] The ring structure of the carboxylic acid dianhydride (B) is preferably at least one selected from the group consisting of a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a benzene ring, and a naphthalene ring, and at least one of a benzene ring and a naphthalene ring is more preferred from the viewpoint of further improving the heat resistance of the resin layer. Furthermore, when forming a resin layer using composition B between multiple substrates, it is preferable to include two or more benzene rings from the viewpoint of suppressing the generation of voids in the resin layer.

[0180] If the carboxylic acid dianhydride (B) has multiple ring structures within the molecule, these ring structures may be the same or different, and may form a fused ring. Alternatively, the multiple ring structures may be linked by single bonds, or they may be linked via linking groups such as ether groups, carbonyl groups, sulfonyl groups, or methylene groups.

[0181] The carboxylic acid dianhydride (B) may contain fluorine atoms in its molecule. For example, it may contain one to six fluorine atoms, or three to six fluorine atoms. For example, the carboxylic acid dianhydride (B) may contain a fluoroalkyl group in its molecule, specifically a trifluoroalkyl group or a hexafluoroisopropyl group.

[0182] Examples of carboxylic acid dianhydrides (B) include dianhydrides of compounds having a ring structure and four carboxyl groups capable of forming anhydride groups within the molecule. For example, anhydrides of alicyclic tetracarboxylic acids such as 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, and 1,2,3,4,5,6-cyclohexanehexacarboxylic acid; Dianhydrides of benzenetetracarboxylic acids such as pyromellitic acid; Dianhydrides of naphthalenetetracarboxylic acids, such as 1,4,5,8-naphthalenetetracarboxylic acid and 2,3,6,7-naphthalenetetracarboxylic acid; Dianhydrides of biphenyltetracarboxylic acids, such as 3,3',4,4'-biphenyltetracarboxylic acid; Dianhydrides of benzophenone tetracarboxylic acids, such as benzophenone-3,3',4,4'-tetracarboxylic acid; Dianhydrides of diphthalic acids such as 4,4'-oxydiphthalic acid (ODPA), 3,4'-oxydiphthalic acid, 1,3-bis(phthalic acid)tetramethyldisiloxane, 4,4'-(ethyn-1,2-diyl)diphthalic acid, 4,4'-(1,4-phenylenebis(oxy))diphthalic acid, 4,4'-([1,1'-biphenyl]-4,4'-diylbis(oxy))diphthalic acid, and 4,4'-((oxybis(4,1-phenylene))bis(oxy))diphthalic acid; Dianhydrides of perylenecarboxylic acids, such as perylene-3,4,9,10-tetracarboxylic acid; Anthracene carboxylic acid dianhydrides such as anthracene-2,3,6,7-tetracarboxylic acid; Dianhydrides of fluorinated aromatic ring carboxylic acids such as 4,4'-(hexafluoroisopropylidene)diphthalic acid, 9,9-bis(trifluoromethyl)-9H-xanthene-2,3,6,7-tetracarboxylic acid, and 1,4-ditrifluoromethylpyromellitic acid; The dianhydride of bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylic acid)1,4-phenylene; 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic acid (IPBDA) dianhydride; Examples include the dianhydride of bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylic acid)1,4-phenylene (TAHQ).

[0183] The amount of carboxylic acid dianhydride (B) in composition B is preferably such that the ratio (A / B) of the number of functional group equivalents A of the silane coupling agent (A) that can react with the anhydride group of carboxylic acid dianhydride (B) to the number of anhydride group equivalents B of carboxylic acid dianhydride (B) is 0.9 to 1.1, more preferably 0.95 to 1.05, and even more preferably 0.98 to 1.02.

[0184] If composition B further contains compounds that can react with the anhydride group of carboxylic acid dianhydride (B), such as compound (C) described later, the ratio (A' / B') of the total functional group equivalent number A' of all compounds that can react with the anhydride group of carboxylic acid dianhydride (B) to the anhydride group equivalent number B' of carboxylic acid dianhydride (B) is preferably 0.9 to 1.1, more preferably 0.95 to 1.05, and even more preferably 0.98 to 1.02.

[0185] (Amine compound (C)) Amine compounds (C) are compounds that have one or more ring structures and one or more amino groups in their molecule, have a molecular weight of 90 to 600, and do not contain Si-O bonds. The amine compound (C) may be used alone or in combination of two or more types.

[0186] The amine compound (C) may have one or more amino groups in its molecule, but from the viewpoint of reducing the thermal expansion coefficient of the resin layer, it is preferable to have more than one amino group, and more preferably two (diamine) or three (triamine) amino groups. From the viewpoint of forming an imide structure in the resin layer to improve heat resistance, it is more preferable to have a primary amino group (-NH2).

[0187] From the viewpoint of reducing the thermal expansion coefficient of the resin layer, the amine compound (C) preferably has one or more amino groups directly bonded to the ring structure. When the structure derived from the amino group directly bonded to the ring structure is included in the molecular structure of the compound (X2), it is considered that the rigidity of the molecular structure increases and the thermal expansion coefficient further decreases.

[0188] In the present disclosure, the "amino group directly bonded to the ring structure" means an amino group bonded to the ring structure by a single bond (that is, without passing through a carbon atom or the like).

[0189] The amine compound (C) may have one ring structure or a plurality of ring structures in the molecule. When the amine compound (C) has a plurality of ring structures in the molecule, the plurality of ring structures may be the same or different, and may form a condensed ring. Alternatively, the plurality of ring structures may be bonded by a single bond or may be bonded via a linking group such as an ether group, a carbonyl group, a sulfonyl group, or a methylene group.

[0190] Examples of the ring structure contained in the amine compound (C) include an alicyclic structure, an aromatic ring (including a heterocyclic ring) structure, and a condensed ring structure thereof. Examples of the alicyclic structure include an alicyclic structure having 3 to 8 carbon atoms, preferably 4 to 6 carbon atoms. The inside of the ring structure may be saturated or unsaturated. More specifically, saturated alicyclic structures such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, and a cyclooctane ring; unsaturated alicyclic structures such as a cyclopropene ring, a cyclobutene ring, a cyclopentene ring, a cyclohexene ring, a cycloheptene ring, and a cyclooctene ring.

[0191] Examples of the aromatic ring structure include an aromatic ring structure having 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms. Specifically, benzene-based aromatic ring structures such as a benzene ring, a naphthalene ring, an anthracene ring, and a perylene ring; non-benzene-based aromatic ring structures such as a pyridine ring, a thiophene ring, an indene ring, and an azulene ring.

[0192] Examples of the heterocyclic structure include a 3- to 10-membered heterocyclic structure, preferably a 5- or 6-membered heterocyclic structure. Examples of the heteroatom contained in the heterocyclic ring include a sulfur atom, a nitrogen atom, and an oxygen atom, and only one of these or two or more thereof may be included. Specific examples of the heterocyclic structure include an oxazole ring, a thiophene ring, a pyrrole ring, a pyrrolidine ring, a pyrazole ring, an imidazole ring, a triazole ring, an isocyanuric ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a piperidine ring, a piperazine ring, a triazine ring, an indole ring, an indoline ring, a quinoline ring, an acridine ring, a naphthyridine ring, a quinazoline ring, a purine ring, a quinoxaline ring, and the like.

[0193] As the ring structure contained in the amine compound (C) in the molecule, a benzene ring, a cyclohexane ring, and a benzoxazole ring are more preferable.

[0194] The ring structure contained in the amine compound (C) in the molecule may have a substituent other than an amino group. For example, it may have an alkyl group having 1 to 6 carbon atoms, an alkyl group substituted with a halogen atom, or the like.

[0195] Specific examples of the amine compound (C) include, for example, the following compounds. Examples of the alicyclic amine include cyclohexylamine, dimethylaminocyclohexane, and the like. Examples of the aromatic ring amine include diaminodiphenyl ether, xylenediamine (preferably para-xylenediamine), diaminobenzene, diaminotoluene, methylenedianiline, dimethyldiaminobiphenyl, bis(trifluoromethyl)diaminobiphenyl (TFDB), diaminobenzophenone, diaminobenzanilide, bis(aminophenyl)fluorene, bis(aminophenoxy)benzene, bis(aminophenoxy)biphenyl, dicarboxydiaminodiphenylmethane, diaminoresorcin, dihydroxybenzidine, diaminobenzidine, 1,3,5-triaminophenoxybenzene, 2,2'-dimethylbenzidine, tris(4-aminophenyl)amine, and the like. For example, heterocyclic amines having a nitrogen-containing heterocycle include melamine, ammeline, melam, melem, and tris(4-aminophenyl)amine. Furthermore, examples of amine compounds that have both heterocyclic and aromatic rings include N2,N4,N6-tris(4-aminophenyl)-1,3,5-triazine-2,4,6-triamine and 2-(4-aminophenyl)benzoxazole-5-amine (AAPD).

[0196] (Method for obtaining compound (X1)) One method for obtaining compound (X1) by reacting a silane coupling agent (A) with a carboxylic acid dianhydride (B) is to gradually add the silane coupling agent (A) dropwise to the carboxylic acid dianhydride (B) while stirring with a solvent.

[0197] (Method for obtaining compound (X2)) One method for obtaining compound (X2) by reacting a silane coupling agent (A), a carboxylic acid dianhydride (B), and an amine compound (C) is to add a solvent to the amine compound (C) and stir, then add the carboxylic acid dianhydride (B), stir until the viscosity of the resulting reactant (polymer) becomes constant, and then gradually add the silane coupling agent (A) dropwise to obtain compound (X2).

[0198] (Precursor of resin (D)) Composition B may further contain compounds other than compounds (X1) and (X2). For example, it may further contain a precursor of resin (D) having a CTE of 90 ppm / K or less between 50°C and 150°C. When composition B contains a precursor of resin (D), the coefficient of thermal expansion of the resulting resin layer tends to be further reduced.

[0199] Specifically, resins (D) having a CTE of 90 ppm / K or less between 50°C and 150°C include at least one selected from the group consisting of polyimides and polybenzoxazoles. The CTE of resin (D) can be measured in the same manner as the CTE of the resin layer.

[0200] If composition B contains resin (D), the proportion of resin (D) in composition B is preferably 99% to 30% by mass of the total nonvolatile content of composition B, from the viewpoint of balancing the thermal expansion coefficient and bonding strength of the resulting resin layer. In this disclosure, "nonvolatile content" refers to components other than those removed when composition B becomes a cured product (solvent, etc.).

[0201] (organic solvent) Composition B may contain an organic solvent. The organic solvent is not particularly limited as long as it can dissolve compound (X). Examples include aprotic solvents, phenolic solvents, etheric solvents, and glycolic solvents. Organic solvents may be used individually or in combination of two or more.

[0202] Examples of aprotic solvents include amide solvents such as N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), N-methylcaprolactam, 1,3-dimethylimidazolidinone, and tetramethylurea; lactone solvents such as γ-butyrolactone and γ-valerolactone; phosphorus-containing amide solvents such as hexamethylphosphoricamide and hexamethylphosphinetriamide; sulfur-containing solvents such as dimethylsulfone, dimethylsulfoxide, and sulfolane; ketone solvents such as cyclohexanone and methylcyclohexanone; tertiary amine solvents such as picoline and pyridine; and ester solvents such as acetic acid (2-methoxy-1-methylethyl). Examples of phenolic solvents include phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, and 3,5-xylenol. Examples of ether-based and glyco-based solvents include 1,2-dimethoxyethane, bis(2-methoxyethyl) ether, 1,2-bis(2-methoxyethoxy)ethane, bis[2-(2-methoxyethoxy)ethyl] ether, tetrahydrofuran, and 1,4-dioxane.

[0203] The organic solvent preferably has a boiling point of 60°C to 300°C at atmospheric pressure, more preferably 140°C to 280°C, and even more preferably 170°C to 270°C. If the boiling point of the solvent is 300°C or lower, the organic solvent is easily volatilized and removed during the resin layer formation process. If the boiling point of the solvent is 60°C or higher, a resin layer with a uniform surface condition can be obtained.

[0204] If composition B contains an organic solvent, its content is not particularly limited. For example, it may be 1.0% by mass or more and 99.99896% by mass or 40% by mass or more and 99.99896% by mass relative to the entire composition B.

[0205] (Other ingredients) Composition B may contain components other than those described above, if necessary. For example, if selectivity for plasma etching resistance is required for composition B (for example, when used as a gap fill material or embedded insulating film), it may contain a metal alkoxide represented by the following general formula (I). R1nM(OR2)mn···(I) (In the formula, R1 is a non-hydrolyzable group, R2 is an alkyl group having 1 to 6 carbon atoms, M represents at least one metal atom selected from the group of metal atoms Ti, Al, Zr, Sr, Ba, Zn, B, Ga, Y, Ge, Pb, P, Sb, V, Ta, W, La, Nd and In, m is the valence of the metal atom M, which is 3 or 4, and n is an integer from 0 to 2 if m is 4, and if m is 3 (The result is either 0 or 1. If there are multiple R1s, each R1 may be identical or different from the others. If there are multiple OR2s, each OR2 may be identical or different from the others.)

[0206] When insulation is required for the film produced from Composition B (for example, for the use of an insulating film for silicon through vias, for the use of an embedded insulating film), in order to improve insulation or mechanical strength, a silane compound (excluding those corresponding to the silane coupling agent (A)) may be included. Specific examples of the silane compound include tetraethoxysilane, tetramethoxysilane, bistriethoxysilylethane, bistriethoxysilylmethane, bis(methyldiethoxysilyl)ethane, 1,1,3,3,5,5 - hexaethoxy - 1,3,5 - tricyclohexasilane, 1,3,5,7 - tetramethyl - 1,3,5,7 - tetrahydroxylcyclosiloxane, 1,1,4,4 - tetramethyl - 1,4 - diethoxydisilylethylene, 1,3,5 - trimethyl - 1,3,5 - trimethyl - 1,3,5 - triethoxy - 1,3,5 - tricyclohexasilane, and the like.

[0207] Composition B may contain benzotriazole or its derivative, for example, in order to suppress the corrosion of copper.

[0208] The pH of Composition B is not particularly limited, but it is preferably 2.0 or more and 12.0 or less. Composition B preferably has a sodium content and a potassium content of 10 mass ppb or less each on an elemental basis. If the sodium or potassium content is 10 mass ppb or less each on an elemental basis, it is possible to suppress the occurrence of disadvantages in the electrical characteristics of semiconductor devices such as malfunction of transistors.

[0209] Composition B preferably has a content of inorganic or resin fillers with a maximum diameter of 0.3 μm or more of 30 mass% or less of the total non - volatile content, more preferably 10 mass% or less, and even more preferably 0 mass%. When the filler content in composition B is within the above range, bonding defects in the laminate can be suppressed even when the thickness of the resin layer formed using composition B is reduced. Furthermore, when laminating a first substrate with a resin layer formed on it onto a second substrate, alignment marks formed on each substrate may be recognized by a machine to perform positioning. When the filler content is within the above range, the transparency of the resin film is improved, enabling more accurate positioning. [Examples]

[0210] The present disclosure will be described in detail below with reference to examples, but the present disclosure is not limited to the following examples. In the following, "water" refers to ultrapure water (Milli-Q water manufactured by Millipore, with a resistance of 18 MΩ·cm (at 25°C) or less).

[0211] [Example 1] <Preparation of a solution containing a resin layer forming material> A solution containing a resin layer forming material was prepared. Details are as follows. As a material for forming a resin layer, 50% by mass of 3-aminopropyldiethoxymethylsilane (3APDES) and 50% by mass of water were blended to obtain solution A containing a hydrolyzed product of 3APDES. Solution B was obtained containing 70% by mass of oxydiphthalic acid half ester (where Y is O and R is an ethyl group in formula (B-2)) and 30% by mass of ethanol. A solution containing a resin layer-forming material was prepared by mixing 24 g of solution A, 18 g of solution B, 20 g of 1-propanol, and 38 g of water.

[0212] <Preparation of the first laminate> A silicon wafer, serving as the first substrate, was placed on a spin coater. 2.0 mL of a solution containing the resin layer-forming material was dropped onto the silicon wafer at a constant rate for 10 seconds. After holding for 23 seconds, the wafer was rotated at 2000 rpm (rpm is rotation speed per minute) for 1 second, then at 600 rpm for 30 seconds, and finally at 2000 rpm for 10 seconds to dry. This applied the resin layer-forming material to the first substrate. A first substrate coated with a resin layer forming material was heated at 200°C for 1 hour under a nitrogen atmosphere. This formed a resin layer (1 μm thick) containing siloxane bonds and imide bonds on the first substrate, thereby obtaining the first laminate. Here, the resin layer includes the following structure, which contains siloxane bonds and imide bonds.

[0213] [ka]

[0214] <Fabrication of the second substrate> As a second substrate, a second substrate was prepared, which included a silicon wafer as the substrate body and an SiO2 layer with a thickness of 0.1 nm to 10 nm formed on the substrate body as an inorganic layer.

[0215] <Surface activation treatment for the resin layer in the first laminate> The resin layer of the first laminate obtained above was subjected to O2 plasma treatment as a surface activation treatment using a plasma processing device (SUSS PL12). In detail, the first laminate was fixed to a metal holder and set in the load lock chamber of the plasma processing device. The load lock chamber was then evacuated to a vacuum of 1.0 × 10⁻⁶. -3 The pressure was reduced to below Pa. The first laminate was transported from the load lock chamber to the plasma processing chamber. Vacuum was evacuated from the plasma processing chamber, and the vacuum level inside the plasma processing chamber was set to 2.0 × 10⁻⁶. -4 The pressure was reduced to below Pa. Oxygen gas was introduced into the plasma processing chamber to adjust the pressure inside the plasma processing chamber. Next, RF power was applied, and the surface of the resin layer in the first laminate was exposed to oxygen gas plasma (i.e., O2 plasma) under the following processing conditions, thereby performing O2 plasma treatment as a surface activation treatment. Next, the plasma processing chamber was evacuated, and the first laminated structure, after plasma processing, was moved to the load lock chamber. The load lock chamber was vented using oxygen gas to open it to the atmosphere, and the first laminated structure, after plasma processing, was removed from the load lock chamber.

[0216] -Processing conditions for surface activation treatment- • Material gas: O2 • Gas flow rate: 35 sccm • Processing pressure: 46.7 Pa • RF power: 100W (reverse sputtering mode: applied to the sample holder.) Processing time: 60 seconds

[0217] <Surface activation treatment for the SiO2 layer on the second substrate> The SiO2 layer of the second substrate was subjected to a surface activation treatment under the same conditions as the surface activation treatment applied to the resin layer of the first laminate.

[0218] <Manufacturing of substrate laminates (bonding of the first laminate to the second substrate)> The resin layer of the first laminate, after surface activation treatment, was washed with water at 25°C for 30 seconds. Next, the first laminate and the second substrate (i.e., the silicon wafer with the SiO2 layer mentioned above) were bonded together at room temperature (25°C) with the resin layer of the first laminate and the SiO2 layer of the second substrate in contact, to obtain a substrate laminate. The bonding conditions were air, room temperature, and pressurization at 0.2 MPa for 1 second.

[0219] <Measurement and Evaluation> The following measurements and evaluations were performed on the above-mentioned substrate laminate.

[0220] (EDX composition analysis) Using a FIB (Focused Ion Beam), thin section samples for cross-sectional observation of the resin layer were cut from the substrate laminate. EDX compositional analysis was performed on the cross-section of the resin layer in the cut-out thin section samples using FIB / TEM (FEI Talos F200X) under conditions of 8600x magnification and 200kV acceleration voltage.

[0221] The proportions (atomic %) shown in Table 1 were determined by EDX compositional analysis. The position where the Si ratio was maximized and the position where the O ratio was maximized were the same. The position where the Si ratio was at its minimum and the position where the O ratio was at its minimum were the same.

[0222] In Example 1, the change in the abundance ratio of Si atoms in the thickness direction of the resin layer, and the change in the abundance ratio of O atoms in the thickness direction of the resin layer, were both continuous.

[0223] (Composite modulus of the resin layer) For the resin layer in the substrate laminate, the unloading-displacement curve was measured at 23°C using a nanoindenter (product name TI-950 Tribo Indenter, manufactured by Hysitron, Berkovich type indenter) at a test depth of 20 nm. The composite modulus of elasticity at 23°C was calculated from the maximum load and maximum displacement according to the calculation method described in the reference (Handbook of Micro / nano Tribology (second Edition), edited by Bharat Bhushan, CRC Press). Here, the composite modulus is defined by the following equation (1). In equation (1), Er represents the composite modulus, Ei represents the Young's modulus of the indenter, which is 1140 GPa, νi represents the Poisson's ratio of the indenter, which is 0.07, and Es and νs represent the Young's modulus and Poisson's ratio of the resin layer, respectively.

[0224]

number

[0225] (Bond strength at room temperature) The bonding strength between the first substrate and the second substrate of the substrate laminate obtained above was determined at room temperature (25°C). The bonding strength at room temperature (25°C) is an example of the bonding strength at low temperatures in this disclosure. The results are shown in Table 1. Here, the bonding strength at room temperature was determined by a blade insertion test according to the method described in MPMaszara, G.Goetz, A.Cavigila, and JBMckitterick, Journal of Applied Physics, 64 (1988) 4943-4950. Specifically, a blade with a thickness of 0.1 mm to 0.3 mm was inserted at room temperature (25°C) into the bonding interface between the first laminate and the second substrate in the substrate laminate (i.e., the bonding interface between the resin layer in the first laminate and the SiO2 layer in the second substrate). The distance from the tip of the blade to the point where the first laminate and the second substrate separated was measured using an infrared light source and an infrared camera. Based on the obtained distance, the surface energy was calculated according to the following formula. The obtained surface energy was defined as the bonding strength. γ = 3 × 10 9 ×t b 2 ×E 2 ×t 6 / (32×L 4 ×E×t 3 ) Here, γ is the surface energy (J / m 2 ), t b θ is the blade thickness (m), E is the Young's modulus (GPa) of the silicon substrate contained in the first laminate and the second substrate, t is the thickness of the first laminate and the second substrate (m), and L is the distance from the blade tip to the point where the first laminate and the second substrate are separated.

[0226] [Comparative Example 1] The same procedure as in Example 1 was followed, except that surface activation treatment was not performed. The results are shown in Table 1.

[0227] [Table 1]

[0228] As shown in Table 1, Example 1, which had a Si ratio of 1.5 or higher, exhibited superior bonding strength between substrates compared to Comparative Example 1, which had a Si ratio of less than 1.5.

[0229] The disclosure of Japanese Patent Application No. 2023-106422, filed on 28 June 2023, is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards described herein are incorporated by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually noted to be incorporated by reference.

Claims

1. The first substrate and A resin layer containing resin, The second circuit board, A substrate laminate comprising the following in this order: Both the first substrate and the second substrate are thicker than the resin layer. The resin contains Si atoms, When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the Si ratio, which is the value obtained by dividing the maximum value of the Si atom abundance in the resin layer by the minimum value of the Si atom abundance in the resin layer, is 1.5 or greater. A laminated substrate.

2. The resin further contains oxygen atoms, When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the oxygen ratio, which is the value obtained by dividing the maximum value of the oxygen atom abundance in the resin layer by the minimum value of the oxygen atom abundance in the resin layer, is 1.3 or greater. The substrate laminate according to claim 1.

3. The first substrate and A resin layer containing resin, The second circuit board, A substrate laminate comprising the following in this order: Both the first substrate and the second substrate are thicker than the resin layer. The aforementioned resin contains an O atom, When the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the oxygen ratio, which is the value obtained by dividing the maximum value of the oxygen atom abundance in the resin layer by the minimum value of the oxygen atom abundance in the resin layer, is 1.3 or greater. A laminated substrate.

4. The substrate laminate according to claim 2 or 3, wherein when the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the change in the ratio of oxygen atoms in the resin layer with respect to the thickness of the resin layer is continuous.

5. The substrate laminate according to claim 1 or claim 2, wherein when the cross-section of the substrate laminate is subjected to compositional analysis by energy-dispersive X-ray spectroscopy, the change in the ratio of Si atoms in the resin layer with respect to the thickness of the resin layer is continuous.

6. The substrate laminate according to claim 1 or claim 3, wherein the composite elastic modulus of the resin layer is 1 GPa to 20 GPa.

7. The substrate laminate according to claim 1 or claim 3, further comprising an electrode penetrating the resin layer between the first substrate and the second substrate.

8. Each of the first substrate and the second substrate includes an inorganic substrate body and an inorganic layer. A substrate laminate according to claim 1 or claim 3.

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