Method for producing laminate, and laminate

Abstract

A method for producing a laminate including two silicon substrates, said method for producing a conductive laminate comprising (a) preparing a first silicon substrate having a first conductive region in at least a part of a surface thereof, and a second silicon substrate, and (b) joining the surface of the first silicon substrate that includes the first conductive region and the second silicon substrate with an adhesive layer, wherein the adhesive layer includes, on a first activation region provided by activating at least a part of the surface of the first silicon substrate that includes the first conductive region, a first reaction product derived from a first organic material capable of reacting with the first activation region.

Description

Method for manufacturing laminate and laminate

[0001] The present invention relates to a method for producing a laminate and to a laminate.

[0002] In the field of semiconductor technology, for example, in Patent Document 1, a method of bonding two silicon substrates has been studied in which an adhesive layer is provided between the silicon substrates.

[0003] International Publication No. 2023 / 276638

[0004] An object of the present disclosure is to provide a new laminate and a method for producing the same.

[0005] To solve the above problems, the present disclosure provides the following [1] to

[23] . [1] A method for manufacturing a laminate including two silicon substrates, comprising: (a) preparing a first silicon substrate having a first conductive region on at least a portion of its surface; and (b) bonding the surface of the first silicon substrate including the first conductive region to the second silicon substrate with an adhesive layer, wherein the adhesive layer contains a first reaction product derived from a first organic material capable of reacting with a first activated region formed by activating at least a portion of the surface of the first silicon substrate including the first conductive region. [2] The manufacturing method according to [1], wherein the first conductive region includes a metal. [3] The manufacturing method according to [2], wherein the metal in the first conductive region is at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru, and Hf. [4] The manufacturing method according to any one of [1] to [3], wherein the surface of the first conductive region is exposed. [5] The manufacturing method according to any one of [1] to [3], wherein at least a portion of the surface of the first conductive region is in contact with the adhesive layer. [6] The manufacturing method according to any one of [1] to [5], wherein the adhesive layer is formed of two or more layers. [7] The manufacturing method according to any one of [1] to [6], wherein the first activation region is provided on at least a portion of the first conductive region and at least a portion of the first silicon substrate, the first conductive region containing at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru, and Hf, the adhesive layer is in contact with the first activation region, and the thickness of the adhesive layer is 5 nm or less. [8] The manufacturing method according to any one of [1] to [7], wherein the second silicon substrate further includes a second conductive region on at least a portion of its surface, and the adhesive layer is provided on a second activation region formed by activating at least a portion of the surface of the second silicon substrate facing the second conductive region, and contains a second reaction product derived from a second organic material. [9] The manufacturing method according to [8], wherein the second conductive region includes a metal.

[10] The manufacturing method according to [8] or [9], wherein the metal of the second conductive region is at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru, and Hf.

[11] The manufacturing method according to any one of [8] to

[10] , wherein the surface of the second conductive region is exposed.

[12] The manufacturing method according to any one of [8] to

[11] , wherein at least a portion of the surface of the second conductive region is in contact with the adhesive layer.

[13] The manufacturing method according to any one of [8] to

[12] , wherein the distance between the first conductive region and the second conductive region is 5 nm or less.

[14] The manufacturing method according to any one of [1] to

[13] , wherein the thickness of the adhesive layer is 5 nm or less.

[15] The manufacturing method according to any one of [8] to

[14] , wherein the first activation region is provided in at least a portion of the first conductive region and at least a portion of the first silicon substrate, the second activation region is provided in at least a portion of the second conductive region and at least a portion of the second silicon substrate, the first conductive region and the second conductive region each contain at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru, and Hf, the adhesive layer is in contact with the first activation region and the second activation region, and the distance between the first conductive region and the second conductive region is 5 nm or less.

[16] A stacked body comprising: a first silicon substrate having a first conductive region on at least a portion of its surface; a second silicon substrate located on the side having the first conductive region; and an adhesive layer located between the first silicon substrate and the second silicon substrate, bonding the side of the first silicon substrate having the first conductive region to the second silicon substrate, wherein conductivity is maintained between the first silicon substrate and the second silicon substrate.

[17] The laminate according to

[16] , wherein the second silicon substrate has a second conductive region on at least a part of its surface, and the adhesive layer bonds the surface having the first conductive region to the surface having the second conductive region.

[18] The laminate according to

[17] , wherein the distance between the first conductive region and the second conductive region is 5 nm or less.

[19] The laminate according to any one of

[16] to

[18] , wherein the thickness of the adhesive layer is 5 nm or less.

[20] The laminate according to any one of

[16] to

[19] , wherein the adhesive layer consists of two or more layers.

[21] The laminate according to any one of

[17] to

[20] , wherein the laminate has the first conductive region and the second conductive region, the distance between the first conductive region and the second conductive region is 5 nm or less, and the adhesive layer bonds a surface having the first conductive region to a surface having the second conductive region.

[22] The conductivity measured at the adhesive layer disposed on the first silicon substrate is 1.0 x 10. －２ ~5.0 x 10 ２

[23] The laminate according to any one of

[16] to

[21] , wherein the resistivity is in the range of 1.5 × 10 －８ ~2.0 x 10 ５ The laminate according to any one of

[16] to

[22] , wherein the modulus of elasticity is in the range of Ω·m.

[0006] According to the present disclosure, a new laminate and a method for producing the same can be provided.

[0007] Fig. 1 shows a schematic cross-sectional view illustrating a portion of a laminate in a first embodiment; Fig. 2 shows a schematic cross-sectional view illustrating a portion of a laminate in a first embodiment; Fig. 3 shows a schematic cross-sectional view illustrating a portion of a laminate in a second embodiment; Fig. 4 shows a schematic cross-sectional view illustrating a portion of a laminate in a modified example.

[0008] Embodiments of the present disclosure will be described in detail below with reference to the drawings, but the present disclosure is not limited to these embodiments.

[0009] 1A, 1B, and 1C are cross-sectional views schematically illustrating a portion of a cross section of a stacked body 40 according to a first embodiment. As shown in FIGS. 1A, 1B, and 1C, the stacked body 40 has a first silicon substrate 10 and a second silicon substrate 20. As shown in FIGS. 1A and 1C, an adhesive layer 30 is located between the first silicon substrate 10 and the second silicon substrate 20. As shown in FIGS. 1A and 1C, a first conductive region 15 and a second conductive region 25 are bonded via the adhesive layer 30.

[0010] 1A to 1C, the laminate 40 can be obtained by a manufacturing method including the following steps: (a) preparing a first silicon substrate 10 having a first conductive region 15 on at least a portion of its surface, and a second silicon substrate 20, and (b) bonding the surface of the first silicon substrate 10 facing the first conductive region 15 to the second silicon substrate 20 with an adhesive layer 30, wherein the adhesive layer 30 includes, on a first activation region 15a formed by activating at least a portion of the surface of the first silicon substrate 10 including the first conductive region 15, a first reaction product derived from a first organic material capable of reacting with the first activation region 15a.

[0011] By having the above-mentioned configuration, a new substrate can be provided.

[0012] Each step will be described below. In the following, unless otherwise specified, "on the first silicon substrate 10" may refer to a state in direct contact with the first silicon substrate 10, or a state in which other layers are included on the first silicon substrate 10. The same applies to other substrates, layers, and regions.

[0013] [Step a] A first silicon substrate 10 having a first conductive region 15 on at least a portion of its surface, and a second silicon substrate 20 are prepared.

[0014] (First and Second Silicon Substrates 10, 20) The first and second silicon substrates 10, 20 (hereinafter collectively referred to as "silicon substrates") may be silicon-based substrates (or base materials), and may consist of silicon or may contain any other suitable substance in addition to silicon. Examples of such other substances include dopants, impurities that may be unavoidably mixed in, metals (e.g., electrodes, wiring, vias, etc.), and oxides, nitrides, and / or carbides of silicon or the like (e.g., dielectric layers, insulator layers, protective layers, etc.).

[0015] The first silicon substrate 10 and the second silicon substrate 20 may have the same configuration or different configurations. In one embodiment, the first silicon substrate 10 and the second silicon substrate have the same configuration. In another embodiment, the first silicon substrate 10 and the second silicon substrate have different configurations.

[0016] The first silicon substrate 10 may have a first bonding portion on its surface. The second silicon substrate 20 may have a second bonding portion on its surface. The first bonding portion and the second bonding portion may be collectively referred to simply as "bonding portion."

[0017] (First and Second Bonding Portions) In this embodiment, the bonding portion may be a portion containing silicon oxide (hereinafter also referred to as a "silicon oxide portion"). The silicon oxide portion may be made of silicon oxide or may contain any other appropriate substance in addition to silicon oxide. Such other substances include, for example, dopants and impurities that may be inevitably mixed in.

[0018] The bonding portion can be formed, for example, by oxidizing (i.e., surface treating) the entire surface or a partial region of the surface of the silicon substrate (typically, one of the two opposing surfaces of the silicon substrate). That is, the first bonding portion may form the entire surface of the surface of the first silicon substrate 10 (typically, one of the two opposing surfaces of the first silicon substrate 10), or a partial region thereof. The second bonding portion may form the entire surface of the surface of the second silicon substrate 20 (typically, one of the two opposing surfaces of the second silicon substrate 20), or a partial region thereof.

[0019] The oxidation of silicon can be achieved by heating in an oxygen-containing atmosphere (so-called thermal oxidation) and / or natural oxidation. For example, the bonded portion of this embodiment can be formed by depositing silicon oxide on the entire surface or a partial region of the surface of the silicon substrate (typically, one of the two opposing surfaces of the silicon substrate). The deposition of silicon oxide may be performed by any one of sputtering, chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), evaporation, or the like, or by combining any two or more of these. The oxidation of silicon and the deposition of silicon oxide may also be performed in combination. However, the present invention is not limited to these methods, and the bonded portion, which is a silicon oxide portion, may be formed by any appropriate method.

[0020] A small number of silanol groups (-Si-OH) are always present on the surface of the bonding portion, which is a silicon oxide portion.

[0021] The thickness of the bonded portion is not particularly limited as long as the desired or acceptable properties are achieved in the final laminate. For example, the thickness of the bonded portion, which is a silicon oxide portion, can be 1 nm or more and 1 μm or less, particularly 10 nm or less. The thickness of the bonded portion can be measured, for example, using a cross-sectional scanning electron microscope (cross-sectional SEM) or SEM, specifically, using SEM.

[0022] 1A and 1B, the first and second conductive regions 15 and 25 are regions through which electricity easily passes, preferably regions containing a metal, and are provided on at least a portion of the first and second silicon substrates 10 and 20. The first and second conductive regions 15 and 25 are, for example, regions containing a conductive metal. The metal preferably contains at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru, and Hf, and more preferably contains Cu. The first conductive region 15 may contain the same metal as the second conductive region 25, or may contain a different metal.

[0023] The first and second conductive regions 15, 25 are formed by, for example, a chemical vapor deposition (CVD) method (e.g., thermal CVD method, plasma CVD method, etc.), a physical vapor deposition (PVD) method (e.g., vacuum deposition method, sputtering method, etc.), an atomic layer deposition (ALD) method, or a plating process (e.g., electroplating, electroless plating, hot-dip plating, etc.).

[0024] The conductivity can be measured, for example, using scanning spreading resistance microscopy (SSRM). For example, the conductivity value can be the average current value of the current values ​​obtained by SSRM.

[0025] The first conductive region 15 may be provided in a range of, for example, 1 to 50% of the surface of the first silicon substrate 10. The second conductive region 25 may be provided in a range of, for example, 1 to 50% of the surface of the second silicon substrate 20.

[0026] When the first silicon substrate 10 has a first junction, the first conductive region 15 is provided on the same surface as the first junction. In this case, the first junction may be provided first and then the first conductive region 15 may be provided, or the first conductive region 15 may be provided first and then the first junction, or the first conductive region 15 and the first junction may be provided simultaneously. The first conductive region 15 and the first junction may partially overlap. That is, the first junction may be provided on the first silicon substrate 10, and then the first conductive region 15 may be provided on at least a portion of the first junction.

[0027] When the second silicon substrate 20 has a second junction, the second conductive region 25 is provided on the same surface as the second junction. In this case, the second junction may be provided first and then the second conductive region 25 may be provided, or the second conductive region 25 may be provided first and then the second junction, or the second conductive region 25 and the second junction may be provided simultaneously. The second conductive region 25 and the second junction may partially overlap. That is, the second junction may be provided on the second silicon substrate 20, and then the second conductive region 25 may be provided on at least a portion of the second junction.

[0028] (First and Second Activation Regions 15a, 25a) Although not essential to this embodiment, the first activation region 15a may be provided in the first silicon substrate 10, and the second activation region 25a may be provided in the second silicon substrate 20.

[0029] The first activated region 15a is a region obtained by activating at least a portion of the surface of the first silicon substrate 10 and / or at least a portion of the surface of the first conductive region 15. The first activated region 15a is formed, for example, by subjecting the surface including the first conductive region 15 to at least one treatment selected from the group consisting of hydrogen atom treatment, heat treatment in a hydrogen-containing atmosphere, sputtering treatment, chemical vapor deposition (CVD), and termination treatment using a chemical solution. This results in H or OH bonding to the first conductive region 15. In one embodiment, the first activated region 15a is formed in a portion of the first conductive region 15. In another embodiment, the first activated region 15a is formed over the entire surface of the first conductive region 15. When multiple first conductive regions 15 are present on the first silicon substrate 10, the first conductive region 15 may not be formed in some of the first activated regions 15a. That is, there may be a first conductive region 15 that does not have a first activated region 15a.

[0030] The second activation region 25a is a region in which at least a portion of the surface of the second silicon substrate 20 and / or at least a portion of the surface of the second conductive region 25 is activated. The second activation region 25a is formed in the same manner as the first activation region 15a. In one embodiment, the second activation region 25a is formed in a portion of the second conductive region 25. In another embodiment, the second activation region 25a is formed over the entire surface of the second conductive region 25. Note that when a plurality of second conductive regions 25 are present on the second silicon substrate 20, the second conductive region 25 may not be formed in some of the second activation regions 25a. That is, there may be a second conductive region 25 that does not have a second activation region 25a.

[0031] In one embodiment, after step (a) and before step (b), at least one of the first and second bonding regions may be subjected to a surface treatment to generate hydrosilyl groups and / or silanol groups, thereby providing the first activated region 15a and / or the second activated region 25a. This allows hydrosilyl groups (—Si—H) and / or silanol groups (—Si—OH) to be present at a higher density on the surface of the bonding region. The surface treatment may be performed on the surface (bonding surface) of the bonding region, and may be performed on only the surface of the bonding region or on a wider surface including the surface of the bonding region. The concentration of hydrosilyl groups and silanol groups on the surface of the bonding region can be measured, for example, from peak intensity by time-of-flight secondary ion mass spectrometry (TOF-SIMS) or using X-ray photoelectron spectroscopy (XPS). The surface treatment may also be performed before providing the first and second conductive regions 15 and 25.

[0032] The surface treatment that generates hydrosilyl groups and / or silanol groups may be at least one selected from the group consisting of hydrogen atom treatment, heat treatment in a hydrogen-containing atmosphere, sputtering treatment, chemical vapor deposition (CVD), and termination treatment using a chemical solution. Hydrogen atoms can be introduced into the surface of the bonded portion by hydrogen atom treatment, heat treatment in a hydrogen-containing atmosphere, sputtering treatment, CVD, or termination treatment using a chemical solution, to generate hydrosilyl groups (-Si-H). Hydroxyl groups can be introduced into the surface of the bonded portion by termination treatment using a chemical solution, to generate silanol groups (-Si-OH).

[0033] The hydrogen atom treatment is carried out, for example, in an ultra-high vacuum (1×10 －６ Hydrogen gas was introduced into a vacuum chamber at a pressure of 1×10 Pa or less. －４ This may be carried out by supplying a pressure of about Pa, dissociating hydrogen molecules into hydrogen atoms by thermal electrons or plasma, and adsorbing the hydrogen atoms onto the surface of the joint.

[0034] The heat treatment in a hydrogen-containing atmosphere may be performed, for example, by creating a vacuum state of a hydrogen atmosphere (specifically, a hydrogen atmosphere of 10 Pa or less) by replacing the atmosphere in the chamber with hydrogen gas by flowing hydrogen as a carrier gas when evacuating the chamber, and then heating the substrate to about 100 to 400°C in this atmosphere to cause hydrogen to be adsorbed onto the surface of the bonding portion.

[0035] The sputtering process may be carried out, for example, by using silicon as a sputtering source to supply hydrogen and allow the hydrogen to be adsorbed on the surface of the joint.

[0036] The CVD process may be carried out, for example, by using silane as the CVD gas and adjusting the hydrogen gas pressure to cause hydrogen atoms to adsorb onto the surface of the joint.

[0037] Termination treatment using a chemical solution may be performed by, for example, immersing the silicon substrate in a chemical solution such as an aqueous solution of hydrofluoric acid (hydrofluoric acid) or ammonium fluoride with at least the bonded portion exposed, and bonding hydrogen ions and / or hydroxide ions to the surface of the bonded portion depending on the chemical solution used.

[0038] In one embodiment, after step (a) and before step (b), at least one of the first bonding portion and the second bonding portion may be subjected to a surface treatment that generates fluorosilyl groups to provide the first activated region 15 a and / or the second activated region 25 a. Note that this surface treatment may be performed before providing the first and second conductive regions 15 and 25.

[0039] The surface treatment that generates fluorosilyl groups may be at least one selected from the group consisting of CVD, discharge treatment, ion implantation, and termination treatment using a chemical solution. The surface treatment that generates fluorosilyl groups may be performed separately from or simultaneously with the surface treatment that generates hydrosilyl groups and / or silanol groups. When performed separately, either of these surface treatments may be performed first.

[0040] The CVD process uses, for example, CF as the CVD gas. ４ and / or science fiction ６This may be achieved by adsorbing fluorine atoms onto the surface of the joint using, for example, a fluorine atom-containing film.

[0041] The discharge treatment is, for example, CF ４ , and / or SF ６ This may be carried out by performing plasma discharge or corona discharge in an atmosphere containing the above, thereby causing fluorine radicals to be adsorbed onto the surface of the joint.

[0042] The ion implantation may involve implanting fluorine ions into the junction in any suitable manner.

[0043] Termination using a chemical solution may be performed by immersing the silicon substrate with at least the bonded portion exposed in a chemical solution such as hydrofluoric acid solution (hydrofluoric acid) or ammonium fluoride, and bonding fluorine ions to the surface of the bonded portion depending on the chemical solution used. In particular, termination using a hydrofluoric acid solution can generate hydrosilyl groups (-Si-H), silanol groups (-Si-OH), and fluorosilyl groups (-Si-F).

[0044] In this manner, the first silicon substrate 10 and the second silicon substrate 20 are prepared.

[0045] [Step b] Next, the surface of the first silicon substrate 10 including the first conductive region 15 and the second silicon substrate 20 are bonded with an adhesive layer 30 .

[0046] When the second silicon substrate 20 includes the second conductive region 25, the distance between the first conductive region 15 and the second conductive region 25, i.e., the distance between the surface of the first conductive region 15 facing the second conductive region 25 and the surface of the second conductive region 25 facing the first conductive region 15, is preferably 5 nm or less, more preferably 3 nm or less, and may be, for example, 2 nm or less, or 1 nm or less. The lower limit of the distance between the first conductive region 15 and the second conductive region 25 is not particularly limited, but may be, for example, 0.2 nm or more. A small distance between the first conductive region 15 and the second conductive region 25 ensures conductivity between the conductive regions. When the distance is large, the adhesive layer 30 generally becomes non-conductive, resulting in insulation between the first conductive region 15 and the second conductive region 25. The distance can be measured, for example, using an ellipsometer.

[0047] The adhesive layer 30 includes a reaction product derived from a first organic material that can react with a first activation region 15a formed by activating at least a portion of the surface of the first silicon substrate 10 that includes the first conductive region 15.

[0048] 1A , at least a portion of the surface of the first active region 15 a opposite to the first silicon substrate 10 is in contact with the adhesive layer 30. At least a portion of the surface of the second active region 25 a opposite to the second silicon substrate 20 is in contact with the adhesive layer 30.

[0049] 1B, the adhesive layer 30 may not be present on the surface of the first activation region 15a, and a void 60 may be present, and the adhesive layer 30 may not be present on the surface of the second activation region 25a, and a void 60 may be present. In other words, the surfaces of the first and second activation regions 15a and 25a may be exposed.

[0050] 1A and 1B, the first activation region 15a and the second activation region 25a are opposed to each other, but different regions may be opposed to each other. For example, the first activation region 15a and the second silicon substrate 20 may be opposed to each other, the first activation region 15a and the second junction portion may be opposed to each other, the second activation region 25a and the second silicon substrate 20 may be opposed to each other, or the second activation region 25a and the first junction portion may be opposed to each other.

[0051] (Adhesive Layer 30) The adhesive layer 30 has a first adhesive portion 31. The adhesive layer 30 (first adhesive portion 31) contains a first reaction product derived from an organic material.

[0052] 1A and 1B, the adhesive layer 30 is provided on at least a portion of the first and second activated regions 15a and 25a. In this case, the adhesive layer 30 and the first and second activated regions 15a and 25a may be chemically reacted with each other or may simply be in contact with each other.

[0053] Preferably, the adhesive layer 30 bonds to, i.e., chemically reacts with, at least a portion of the first and second activated regions 15 a, 25 a. Note that the organic material may bond to the first activated region 15 a but not to the second activated region 25 a, or may bond to the second activated region 25 a but not to the first activated region 15 a.

[0054] As shown in Figure 1C, the adhesive layer 30 may be in direct contact with the first and second silicon substrates 10 and 20. Although the first silicon substrate 10 and the second silicon substrate 20 are shown facing each other in Figure 1C, different substrates, regions, etc. may be provided facing each other. For example, the first silicon substrate 10 and the second activation region 25a may be provided facing each other, the first silicon substrate 10 and the second bonding portion may be provided facing each other, the second silicon substrate 20 and the first activation region 15a may be provided facing each other, or the second silicon substrate 20 and the first bonding portion may be provided facing each other.

[0055] The adhesive layer 30 may be provided on at least a portion of the first conductive region 15. When viewed from a direction perpendicular to the first conductive region 15 (first silicon substrate 10), the adhesive layer 30 may cover the entire first activation region 15a and may also cover at least a portion of the first conductive region 15, or it may cover a portion of the first activation region 15a but not be provided on the first conductive region 15 (i.e., the entire surface of the first conductive region 15 is exposed). That is, the surface of the first conductive region 15 may be exposed, or at least a portion may be in contact with the adhesive layer 30.

[0056] The adhesive layer 30 may be provided on at least a portion of the second conductive region 25. When viewed from a direction perpendicular to the first conductive region 15 (second silicon substrate 20), the adhesive layer 30 may cover the entire second activation region 25a and further cover at least a portion of the second conductive region 25, or it may cover a portion of the second activation region 25a but not be provided on the second conductive region 25 (i.e., the entire surface of the second conductive region 25 is exposed). That is, the surface of the second conductive region 25 may be exposed, or at least a portion may be in contact with the adhesive layer 30.

[0057] The adhesive layer 30 may be provided on the first bonding portion and react with the first bonding portion. The adhesive layer 30 may further be provided on the second bonding portion and react with the second bonding portion. As a result, the adhesive layer 30 bonds the first bonding portion and the second bonding portion. Note that a portion of the first bonding portion may be exposed, or the entire first bonding portion may be covered with the adhesive layer 30. Also, a portion of the second bonding portion may be exposed, or the entire second bonding portion may be covered with the adhesive layer 30.

[0058] The adhesive layer 30 (first adhesive portion 31) may be formed of, for example, two or more layers. That is, a first adhesive layer may be provided on the first silicon substrate 10, dried and / or heated as necessary, and then a second adhesive layer may be provided. The number of layers in the adhesive portion is not particularly limited, but may be, for example, five or less layers.

[0059] The thickness of the adhesive layer 30 (e.g., the distance between the first activated region 15a and the second activated region 25a) can be extremely thin. The thickness of the adhesive layer 30 is, for example, 10 nm or less, and may be particularly 8 nm or less, 5 nm or less, 3 nm or less, or 1.5 nm or less. The lower limit of the thickness of the adhesive layer 30 is not particularly limited, but may be, for example, 1 nm or more. When the thickness of the adhesive layer 30 is within the above range, the distance between the first conductive region 15 and the second conductive region 25 is reduced, thereby ensuring conductivity between the conductive regions. Because the adhesive layer 30 generally does not conduct electricity, a larger thickness results in insulation between the first conductive region 15 and the second conductive region 25. The thickness of the adhesive layer 30 can be measured, for example, using a cross-sectional SEM, SEM, or ellipsometer, specifically, a high-speed mapping spectroscopic ellipsometer (theta-SE).

[0060] The amount of particles contained on the surface of the first adhesive portion 31 opposite to the first silicon substrate 10 is preferably 0 particles / mm ２ The particle amount may be measured by placing the composition on a separately prepared substrate, drying the composition, and then measuring the amount of particles on the surface after drying.

[0061] The amount of particles can be measured using, for example, a surface foreign matter inspection device. The measurement can be performed, for example, in an inspection area of ​​300 mm x 300 mm.

[0062] By keeping the particle amount within the above range, the adhesive strength between the first silicon substrate 10 and the second silicon substrate 20 is improved. Furthermore, the laminate 40 can be manufactured at a relatively low temperature, which effectively suppresses or prevents the generation of voids in the adhesive layer 30. The adhesive strength can be measured using, for example, an ultrasonic microscope.

[0063] Here, the particles may be individual particles or aggregates of particles. That is, particles include primary particles and secondary particles. Furthermore, particles may be inorganic or organic. Examples of particles include particles present in the environment or particles supplied together with an organic material, which exist in particulate form after the organic material has hardened.

[0064] The particle diameter of a particle means a light scattering equivalent diameter that can be quantified using a measuring device. The particle diameter can be measured, for example, using a surface foreign matter inspection device or a liquid particle counter. The particle diameter can be measured, for example, using a surface foreign matter inspection device under conditions of 60 nm or more.

[0065] The lower limit of the particle amount is not particularly limited, but for example, 0 particles / mm ２ The particle size of the particles is, for example, 200 nm or more. There is no particular upper limit to the particle size, but it may be, for example, 6 μm or less.

[0066] In the first embodiment, the first adhesive portion 31 is provided on the first joint portion, but the first adhesive portion 31 may be provided on the second joint portion. In this case, the "first joint portion" is read as the "second joint portion."

[0067] (Organic Material) The organic material is a material capable of reacting with a hydrosilyl group and / or a silanol group. The organic material has at least two functional groups. The two functional groups are preferably located at both ends of the organic material.

[0068] The organic material reacts with the first activated region 15a at the functional group at one end to form a reaction product, the composition of which depends on the structure of the organic material.

[0069] The organic material can react with the second activated region 25a at the functional group at the other end, and the first silicon substrate 10 and the second silicon substrate 20 are bonded together by a reaction product derived from the organic material.

[0070] When the first silicon substrate 10 has a first bonding portion, the organic material can react with the first bonding portion. When the second silicon substrate 20 has a second bonding portion, the organic material can react with the second bonding portion. With the above configuration, the adhesive strength between the first silicon substrate 10 and the second silicon substrate 20 is improved.

[0071] Preferably, the amount of particles in the organic material is 500 particles / mL or less. The lower limit of the amount of particles in the organic material is not particularly limited, but may be, for example, 0 particles / mL or more. The amount of particles in the organic material can be measured using, for example, a syringe sampling system SLS-1040.

[0072] Preferably, the method includes purifying the organic material by filtering, which removes particles contained in the organic material and reduces the amount of particles contained in the first adhesive portion 31.

[0073] The organic material may be used as a composition containing, for example, a solvent. The composition may contain, in addition to the organic material, a solvent and a reaction accelerator such as an acid or base catalyst. A commonly used solvent may be used as the solvent, such as propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, toluene, tetrahydrofuran, or isopropyl alcohol. The water content of the composition is essentially zero. By lowering the water content in the composition in this manner, the generation of voids can be reduced.

[0074] The composition may dissolve, disperse, or suspend the organic material in a solvent. For example, the composition dissolves the organic material.

[0075] The amount of particles in the composition is, for example, 500 particles / mL or less. The lower limit of the amount of particles in the composition is not particularly limited, but is, for example, 0 particles / mL or more.

[0076] Preferably, the method includes purifying the composition by filtering, which removes particles contained in the composition and reduces the amount of particles contained in the first adhesive portion 31.

[0077] Preferably, the filtering is performed using a membrane with an effective diameter of 100 nm or less. The effective diameter of the membrane is more preferably 50 nm or less, and even more preferably 10 nm or less. The lower limit of the effective diameter of the membrane is not particularly limited, but may be, for example, 1 nm or more. Here, the effective diameter refers to the average effective diameter of the membrane.

[0078] Specific aspects of the method for supplying the organic material (or a composition containing the organic material) and the bonding method may be selected appropriately depending on the organic material used. Generally, after the organic material is supplied to the first bonding portion, the first silicon substrate 10 and the second silicon substrate 20 may be maintained under predetermined reaction conditions (particularly, a predetermined temperature) with the organic material interposed between them, thereby allowing the reaction to proceed. The organic material may also be supplied to the second bonding portion instead of the first bonding portion.

[0079] For example, an organic material (which may be a composition) is applied (e.g., by coating, spraying, printing, etc.) to one or both of the surface of the first silicon substrate 10 having the first conductive region 15 (the surface having at least a portion of the first activated region 15a) and the surface of the second silicon substrate having the second conductive region 25 (the surface having at least a portion of the second activated region 25a). The organic material may be applied in its original form or in the form of a composition mixed with any appropriate component (e.g., a solvent, etc.). Washing and / or drying may then be performed as necessary. The washing and drying may be similar to those described above. When a fluorine-containing organic material is used, pre-washing using a fluorine-based solvent may be performed.

[0080] The first silicon substrate 10 and the second silicon substrate 20 are then aligned so that the first conductive region 15 and the second conductive region 25 face each other, and the first silicon substrate 10 and the second silicon substrate 20 are brought into close contact with each other with the organic material interposed therebetween. The first silicon substrate 10 and the second silicon substrate 20 that have been brought into close contact with each other are maintained under predetermined reaction conditions (particularly, a predetermined temperature) to allow the reaction to proceed. An annealing process may then be performed as necessary.

[0081] As another example, an organic material (or a composition containing an organic material) may be supplied to the surface on the side having the first conductive region 15 (the surface having the first activation region 15a at least in part), and then the first silicon substrate 10 and the second silicon substrate 20 may be maintained under predetermined reaction conditions (particularly a predetermined temperature) with the organic material interposed between the first conductive region 15 and the second conductive region 25, thereby bonding the first silicon substrate 10 and the second silicon substrate 20 with a reaction product.

[0082] In one embodiment, when an organic material is applied to the surface of the first conductive region 15, the surface of a layer formed from the organic material may be washed with water or a water-containing organic solvent, and then the second conductive region 25 may be disposed on the layer. Note that the organic material may be applied to the surface of the second conductive region 25 instead of the surface of the first conductive region 15.

[0083] The functional group of the organic material has at least one selected from the group consisting of, for example, an alkenyl group, a hydroxyl group, a hydrolyzable silyl group, an isocyanate group, an epoxy group, an amino group, an acid anhydride group, and a siloxane bond. The alkenyl group can react with a hydrosilyl group (-Si-H), and the hydroxyl group, the hydrolyzable silyl group, the isocyanate group, the epoxy group, the amino group, the acid anhydride group, and the siloxane bond can react with a silanol group (-Si-OH).

[0084] More specifically, the organic material may include at least one selected from the group consisting of the following (i) to (iv). The organic material may be a single compound or a combination of two or more compounds. While the following describes the reaction of the organic material with the first and second activated regions 15a and 25a, or the reaction of the organic material with the first and second bonding portions, other combinations of reactions are also possible. For example, the organic material may react with the first activated region 15a and the second bonding portion, or with the second activated region 25a and the first bonding portion. (i) A substituted or unsubstituted hydrocarbon compound having alkenyl groups at two terminals. (ii) A substituted or unsubstituted hydrocarbon compound having an alkenyl group at one terminal and a group selected from the group consisting of a hydroxyl group, a hydrolyzable silyl group, an isocyanate group, an epoxy group, an amino group, and an acid anhydride group at the other terminal. (iii) a substituted or unsubstituted hydrocarbon compound having at its two terminals any one independently selected from the group consisting of a hydroxyl group, a hydrolyzable silyl group, an isocyanate group, an epoxy group, an amino group, a phosphoric acid group, and an acid anhydride group, and (iv) silsesquioxane and its derivatives.

[0085] Exemplary embodiments using organic materials (i) to (iv) are described in detail below.

[0086] (i) Example using organic material (First Example) In this example, first and second conductive regions 15, 25 are formed on parts of the surfaces of the first silicon substrate 10 and the second silicon substrate 20. The first and second conductive regions have first and second activated regions 15a, 25a, at least parts of which are activated. The first and second activated regions 15a, 25a may have, for example, hydrogen atoms on their surfaces.

[0087] Furthermore, the first silicon substrate 10 and the second silicon substrate 20 may have a first bonding portion and a second bonding portion (which are silicon oxide portions in this example). Hydrosilyl groups (—Si—H) may be present on the surfaces of the first and second bonding portions. The first silicon substrate 10 and the second silicon substrate 20 having hydrosilyl groups on the surfaces of the first and second bonding portions, which are silicon oxide portions, may be obtained, for example, by the surface treatment described above that generates hydrosilyl groups.

[0088] The organic material is a substituted or unsubstituted hydrocarbon compound having alkenyl groups at two ends. The alkenyl groups are reactive groups to hydrogen atoms in activated regions and / or hydrosilyl groups at junctions. Such compounds may have two or more ends, and may have alkenyl groups at any two or more ends. Such compounds may be fluorine-substituted, i.e., may be fluoroalkyl compounds or fluoropolyether group-containing compounds having alkenyl groups at two or more ends.

[0089] As an example, fluoroalkyl compounds having alkenyl groups at two, three, or four terminal positions are shown below. Rf represents a fluoroalkyl group (the same applies below). In the following compounds, for example, the alkenyl groups may be bonded to different carbon atoms contained in Rf.

[0090]

[0091] The number of carbon atoms in the portion excluding the terminal reactive group (alkenyl group) is not particularly limited, but may be, for example, 1 to 200, inclusive, particularly 100 or less. The number of carbon atoms may be, for example, 5 or more. The portion excluding the reactive group may be linear, branched, or cyclic. When the portion excluding the terminal reactive group is a fluoroalkyl group, the fluorine substitution ratio is not particularly limited, but may be, for example, a perfluoroalkyl group.

[0092] The fluoropolyether group-containing compound having alkenyl groups at two or more terminals is, for example, a compound represented by the formula (A) (1): [In the formula: R Ｆ２ is -Rf２ ｐ -R Ｆ -O ｑ -; Rf ２ is a C optionally substituted by one or more fluorine atoms; １－２０ is an alkylene group; R Ｆ is independently at each occurrence a group represented by the formula: ６ F １２ ) ａ - (OC ５ F １０ ) ｂ - (OC ４ F ８ ) ｃ - (OC ３ R Ｆａ ６ ) ｄ - (OC ２ F ４ ) ｅ -(OCF ２ ) ｆ - (wherein, R Ｆａ are each independently a hydrogen atom, a fluorine atom, or a chlorine atom in each occurrence; a, b, c, d, e, and f are each independently an integer of 0 to 200, the sum of a, b, c, d, e, and f is 1 or more, and the order of the repeating units enclosed in parentheses with a, b, c, d, e, or f is arbitrary in the formula, provided that all R Ｆａ is a hydrogen atom or a chlorine atom, at least one of a, b, c, e and f is 1 or more; p is 0 or 1; q is 0 or 1; R Ｄ is CH ２ =CH-; X Ａ are each independently a single bond or a divalent to decavalent organic group; and γ is each independently an integer of 1 to 9.] or (B) a compound represented by formula (2): [In the formula: R Ｎ teeth, and R Ｆ２ is -Rf ２ ｐ -R Ｆ -O ｑ -; Rf ２is a C optionally substituted by one or more fluorine atoms; １－６ is an alkylene group; R Ｆ is independently at each occurrence a group represented by the formula: ６ F １２ ) ａ - (OC ５ F １０ ) ｂ - (OC ４ F ８ ) ｃ - (OC ３ R Ｆａ ６ ) ｄ - (OC ２ F ４ ) ｅ -(OCF ２ ) ｆ - (wherein, R Ｆａ are each independently a hydrogen atom, a fluorine atom, or a chlorine atom in each occurrence; a, b, c, d, e, and f are each independently an integer of 0 to 200, the sum of a, b, c, d, e, and f is 1 or more, and the order of the repeating units enclosed in parentheses with a, b, c, d, e, or f is arbitrary in the formula, provided that all R Ｆａ is a hydrogen atom or a chlorine atom, at least one of a, b, c, e and f is 1 or more; p is 0 or 1; q is 0 or 1; X ａ is independently in each occurrence a single bond or a divalent organic group; R Ａ１ are each independently in each occurrence: OR Ａｃ R is a group-containing group; Ａｃ is a (meth)acryloyl group; R Ｂ represents, independently at each occurrence, R Ｆ１ -X ａ - or R Ａ１ -X ｂ - and R Ｆ１ is Rf １ -R Ｆ -O ｑ -; Rf １ is a C optionally substituted by one or more fluorine atoms;１－１６ is an alkyl group, ｂ is a divalent organic group.]. In addition, R Ｎ In the formula, any of the bonding groups is X ａ In the formula on the right, the left side is X ａ , and the right side is X ｂ or R Ｂ Also, R Ｆ In the above formula, the sum of a, b, c, d, e, and f may be, for example, 5 or more.

[0093] The organic material is supplied between the first silicon substrate 10 and the second silicon substrate 20 and reacted. The organic material may react with the first and second activated regions 15a and 25a. Specifically, alkenyl groups of the organic material may react with hydrogen atoms in the first and second activated regions 15a and 25a, respectively. Furthermore, if the first and second silicon substrates 10 and 20 have first and second bonding regions, respectively, the alkenyl groups of the organic material may react with hydrosilyl groups in the first and second bonding regions (hydrosilylation). As a result, reaction products derived from the organic material chemically bond to the metals in the first and second activated regions 15a and 25a and / or Si atoms in the first and second bonding regions. This reaction does not produce by-products, fundamentally eliminating the problem of void formation due to by-products.

[0094] The reaction may be carried out in one step with the organic material sandwiched between the first silicon substrate 10 and the second silicon substrate 20, or may be carried out in two steps by applying the organic material to one of the first silicon substrate 10 or the second silicon substrate 20 to partially promote the reaction, and then placing the other substrate on top of the organic material to further promote the reaction.

[0095] As an example, the reaction when a fluoroalkyl compound having alkenyl groups at two terminals is used is shown below. Note that, in the following, Cu is described as an example of the first and second conductive regions 15, 25. The same applies to the case of a fluoropolyether group-containing compound having alkenyl groups at two terminals.

[0096]

[0097] As shown in the schematic diagram above, the first reaction product derived from the organic material chemically bonds to both the metal atoms in the first conductive region 15 and the metal atoms in the second conductive region 25. However, it is not necessary for all reaction products to chemically bond to both the metal atoms in the first conductive region 15 and the Si atoms of the metal atoms in the second conductive region 25. Some reaction products may be chemically bonded to only one of the metal atoms in the first conductive region 15 and the metal atoms in the second conductive region 25, or may be chemically bonded to two or more metal atoms. To obtain higher bonding strength, it is preferable that more reaction products chemically bond to both the metal atoms in the first conductive region 15 and the metal atoms in the second conductive region 25. From this perspective, the organic material is preferably, but is not limited to, a linear compound having alkenyl groups at both ends.

[0098] Furthermore, the first reaction product derived from the organic material chemically bonds to both the Si atoms of the first bonding portion and the Si atoms of the second bonding portion. However, it is not necessary for all reaction products to chemically bond to both the Si atoms of the first bonding portion and the Si atoms of the second bonding portion. Some reaction products may be chemically bonded to only one of the Si atoms of the first bonding portion and the Si atoms of the second bonding portion, or may be chemically bonded to two or more Si atoms within the same silicon substrate. To obtain higher bonding strength, it is preferable for more reaction products to chemically bond to both the Si atoms of the first bonding portion and the Si atoms of the second bonding portion.

[0099] Although not shown in the schematic diagram, the first reaction product derived from the organic material may bond a Si atom of the first or second bonding portion to a metal atom of the first or second conductive region 15, 25. From the above viewpoint, the organic material is preferably, but is not limited to, a linear compound having alkenyl groups at both ends.

[0100] The first reaction product may bond only to both the metal atoms of the first conductive region 15 and the metal atoms of the second conductive region 25, and may not bond to the Si atoms of the first or second junction. Similarly, in the following examples, the first reaction product may bond only to the metal atoms, and may not bond to the Si atoms.

[0101] (Second Example) In the first example, the first reaction product chemically reacted between the first and second silicon substrates 10, 20 and between the first and second conductive regions 15, 25, connecting them together. However, in the second example, there is a portion A between the first and second conductive regions 15, 25 that is unreacted with the first and second conductive regions 15, 25, and no chemical reaction occurs between the first and second conductive regions 15, 25 and portion A. In other words, the first and second conductive regions 15, 25 are not chemically connected via portion A. Other than that, the configuration is similar to the first example. For example, the first reaction product is present between the first and second silicon substrates 10, 20, and chemically reacts with the surfaces of the first and second silicon substrates 10, 20 to connect them together. This improves the bonding strength between the first and second silicon substrates 10, 20.

[0102] The first and second conductive regions may have first and second activated regions 15a, 25a, at least a portion of which is activated, but may not have the first and second activated regions 15a, 25a.

[0103] For example, as shown in the schematic diagram, when a fluoroalkyl compound having alkenyl groups at two terminals is used, a chemical reaction proceeds at the first and second bonding portions in the same manner as in the first example.

[0104]

[0105] Portion A exists between the metal atoms of the first conductive region 15 and the metal atoms of the second conductive region 25. Portion A is located in at least a portion of the first and second conductive regions 15, 25. It is unreacted with the metal atoms of the first conductive region 15 and the second conductive region 25. Note that the entire surface of the first conductive region 15 and the second conductive region 25 may have portion A, or only a portion may have portion A, with the other portions not having portion A.

[0106] The portion A may contain an organic compound (hereinafter referred to as "unreacted organic compound") that has not reacted with the metal atoms of the first conductive region 15 and the second conductive region 25. The unreacted organic compound is preferably a conductive compound. The conductivity of the portion A is, for example, 1.0×10 －２ ~5.0 x 10 ２ It may be in the pA range.

[0107] Part A may include, for example, an oil, etc. Examples of the oil include (non-reactive) fluoro(poly)ether compounds, which may be understood as fluorine-containing oils, preferably perfluoro(poly)ether compounds (hereinafter referred to as "fluorine-containing oils").

[0108] The fluorine-containing oil is not particularly limited, but examples thereof include compounds represented by the following general formula (I) (perfluoro(poly)ether compounds): ５ - (OC ４ F ８ ) ａ’ - (OC ３ F ６ ) ｂ’ - (OC ２ F ４ ) ｃ’ -(OCF ２ ) ｄ’ -Rf ６ ...(I)

[0109] In the formula, Rf ５ is an alkyl group having 1 to 16 carbon atoms (preferably C １―１６ Rf represents a perfluoroalkyl group ６ is an alkyl group having 1 to 16 carbon atoms (preferably C １－１６ Rf represents a perfluoroalkyl group, a fluorine atom, or a hydrogen atom; ５ and Rf ６ More preferably, each independently represents C １－３ It is a perfluoroalkyl group.

[0110] a', b', c' and d' respectively represent the number of four types of repeating units of the perfluoro(poly)ether constituting the main skeleton of the polymer, and are each independently an integer of 0 to 300, and the sum of a', b', c' and d' is at least 1, preferably 1 to 300, more preferably 20 to 300. The order of occurrence of each repeating unit enclosed in parentheses with the subscript a', b', c' or d' is arbitrary in the formula. Among these repeating units, -(OC ４ F ８ )- is -(OCF ２ CF ２ CF ２ CF ２ )-,-(OCF(CF ３ )CF ２ CF ２ ) -, -(OCF ２ CF (CF ３ )CF ２ ) -, -(OCF ２ CF ２ CF (CF ３ )) -, -(OC(CF ３ ) ２ CF ２ ) -, -(OCF ２ C (CF ３ ) ２ )-,-(OCF(CF ３ )CF(CF ３ ))-,-(OCF(C ２ F ５ )CF ２ )- and -(OCF ２ CF (C ２ F ５ ))-, but preferably -(OCF ２ CF ２ CF ２ CF ２ )-. -(OC ３ F ６ )- is -(OCF ２ CF ２ CF ２ )-,-(OCF(CF ３ )CF ２ )- and -(OCF ２ CF (CF ３ ))-, and preferably -(OCF２ CF ２ CF ２ )-. -(OC ２ F ４ )- is -(OCF ２ CF ２ )- and -(OCF(CF ３ ))-, but preferably -(OCF ２ CF ２ )-.

[0111] Examples of the perfluoro(poly)ether compound represented by the above general formula (I) include compounds represented by either of the following general formulas (Ia) and (Ib) (which may be one type or a mixture of two or more types): ５ -(OCF ２ CF ２ CF ２ ) ｂ’’ -Rf ６ ... (Ia) Rf ５ -(OCF ２ CF ２ CF ２ CF ２ ) ａ’’ -(OCF ２ CF ２ CF ２ ) ｂ’’ -(OCF ２ CF ２ ) ｃ’’ -(OCF ２ ) ｄ’’ -Rf ６ ... (Ib) In these formulas, Rf ５ and Rf ６ is as defined above; in formula (Ia), b" is an integer of 1 or more and 100 or less; in formula (Ib), a" and b" are each independently an integer of 1 or more and 30 or less, and c" and d" are each independently an integer of 1 or more and 300 or less. The order of occurrence of each repeating unit enclosed in parentheses with the subscripts a", b", c", and d" is arbitrary in the formula.

[0112] The fluorinated oil may have a number average molecular weight of 1,000 to 30,000. In particular, the number average molecular weight of the compound represented by formula (Ia) is preferably 2,000 to 8,000. In one embodiment, the number average molecular weight of the compound represented by formula (Ib) is 3,000 to 8,000. In another embodiment, the number average molecular weight of the compound represented by formula (Ib) is 8,000 to 30,000.

[0113] From another viewpoint, the fluorine-containing oil may be a compound represented by the general formula Rf′-F (wherein Rf′ is C ５－１６ The compound represented by Rf'-F and the chlorotrifluoroethylene oligomer may be a compound represented by Rf'-F, where Rf is a perfluoroalkyl group. １－１６ This is preferred in that it provides high affinity with the perfluoro(poly)ether group-containing silane compound, which is a perfluoroalkyl group.

[0114] Note that portion A may include a void or may have only a void. That is, a void may exist between the first conductive region 15 and the second conductive region 25. Furthermore, the unreacted organic compound contained in portion A may exist in another portion, specifically, between the first and second silicon substrates 10 and 20, for example, between the first and second silicon substrates 10 and 20 bonded by a fluoroalkyl compound.

[0115] In the following examples, part A may have a similar configuration.

[0116] (ii) Example using organic material (Third Example) In this example, first and second conductive regions 15, 25 are formed on portions of the surfaces of the first silicon substrate 10 and the second silicon substrate 20. The first and second conductive regions have first and second activated regions 15a, 25a, at least portions of which are activated. For example, the first activated region 15a may have hydroxyl groups on its surface, and the second activated region 25a may have hydrogen atoms on its surface.

[0117] Furthermore, the first silicon substrate 10 and the second silicon substrate 20 may have a first bonding portion and a second bonding portion (which are silicon oxide portions in this example). The first silicon substrate 10 used has silanol groups (-Si-OH) on the surface of the first bonding portion (which is the silicon oxide portion in this example). The first silicon substrate 10 having silanol groups on the surface of the first bonding portion, which is the silicon oxide portion, does not require any particular surface treatment, but may be obtained, if necessary, by the above-mentioned surface treatment that generates silanol groups.

[0118] The organic material is a substituted or unsubstituted hydrocarbon compound having an alkenyl group at one end and a hydroxyl group at the other end. The alkenyl group is reactive with the hydroxyl groups of the first activated region 15a and / or the hydrosilyl groups of the first bonding region, while the hydroxyl group is reactive with the hydrogen atoms of the second activated region 25a and / or the silanol groups of the second bonding region. Such a compound may have two or more end portions, and may have an alkenyl group at any one or more end portions and a hydroxyl group at any one or more end portions. Such a compound may be fluorine-substituted; in other words, it may be a fluoroalkyl compound or a fluoropolyether group-containing compound having an alkenyl group at one end and a hydroxyl group at the other end.

[0119] Unless otherwise specified, the above description may be applied (except for having a hydroxyl group at at least one terminal, the fluoroalkyl compound or the fluoropolyether group-containing compound may be the same as the fluoroalkyl compound or the fluoropolyether group-containing compound described in detail in (i) above).

[0120] The organic material is supplied between the first silicon substrate 10 and the second silicon substrate 20. At this time, the organic material is supplied so as to contact the opposing first and second activated regions 15a and 25a. As a result, a reaction product derived from the first organic material chemically bonds to the metal atoms of the first and second activated regions 15a and 25a, and the first conductive region 15 and the second conductive region 25 are bonded by the reaction product derived from the organic material. Furthermore, the organic material is supplied between the first bonding portion and the second bonding portion to cause a reaction between the hydroxyl groups of the first organic material and the silanol groups of the first bonding portion (etherification by dehydration) and also to cause a reaction between the alkenyl groups of the organic material and the hydrosilyl groups of the second bonding portion (hydrosilylation). As a result, the reaction product derived from the first organic material chemically bonds to the Si atoms of the first bonding portion and the Si atoms of the second bonding portion, and the first bonding portion and the second bonding portion are bonded by the reaction product derived from the organic material.

[0121] More specifically, an organic material is supplied, and hydroxyl groups of the organic material are reacted with hydroxyl groups of the first activated region 15a (first stage). At this time, hydroxyl groups of the organic material may also be reacted with silanol groups of the first bonding portion. Preferably, the first conductive region 15 and the second conductive region 25 are then arranged opposite each other, and hydrogen atoms of the second activated region 25a are reacted with alkenyl groups of the organic material (second stage). At this time, alkenyl groups of the organic material may also be reacted with hydrosilyl groups of the second bonding portion. According to this procedure, water is generated as a by-product in the first reaction stage. However, this by-product can be removed without being trapped between the first silicon substrate 10 and the second silicon substrate 20. Furthermore, since no by-products are generated in the second reaction stage, void formation due to the by-products can be avoided.

[0122] As an example, the reaction when using a fluoroalkyl compound having an alkenyl group at one end and a hydroxyl group at the other end is shown below. Note that Cu is used below as an example of the first and second conductive regions 15, 25. Although only the reaction in the first and second activated regions 15a, 25a is described below, the same reaction can occur in the first and second junctions as in the first and second activated regions 15a, 25a. The same applies to a fluoropolyether group-containing compound having an alkenyl group at one end and a hydroxyl group at the other end.

[0123] In order to obtain higher bonding strength, the organic material is preferably a straight-chain compound having an alkenyl group and a hydroxyl group at both ends, but is not limited to this.

[0124] Furthermore, in this example, a material having hydroxyl groups on the surface of the first activation region 15a and silanol groups on the surface of the first junction is used, and a material having hydrogen atoms on the surface of the second activation region 25a and hydrosilyl groups on the surface of the second junction is used. Therefore, when using an organic material (preferably linear) having hydroxyl groups and alkenyl groups at both ends, it is possible to prevent the reaction product from chemically bonding to two or more Si atoms within the same silicon substrate, thereby achieving even higher bonding strength.

[0125] (Fourth Example) In the third example, the organic material chemically reacts with the first and second conductive regions 15, 25 to connect the first and second conductive regions 15, 25, but the fourth example differs in that part A is present on at least a portion of the surface of the first and second conductive regions 15, 25, and no chemical reaction occurs between the first and second conductive regions 15, 25 and part A. In other words, the first and second conductive regions 15, 25 are not chemically connected via part A. The rest of the configuration is the same as in the third example, and part A has the same configuration as in the second example.

[0126] The above describes an example of using a substituted or unsubstituted hydrocarbon compound having an alkenyl group at one end and a hydroxyl group at the other end as the organic material. However, instead of or in addition to the hydroxyl group, a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group, an isocyanate group, an epoxy group, an amino group, or an acid anhydride group may also be used. Hydroxyl groups, hydrolyzable silyl groups, isocyanate groups, epoxy groups, amino groups, and acid anhydride groups can all function as groups reactive with silanol groups. (Note that the substituted or unsubstituted hydrocarbon compound having an alkenyl group at one end and a hydroxyl group at the other end may be similar to the substituted or unsubstituted hydrocarbon compound having hydrolyzable silyl groups at two ends, described in detail in (iii) below, except for having an alkenyl group at at least one end.)

[0127] First Example (Fifth Example) Using Organic Material (iii) In this example, first and second conductive regions 15, 25 are formed on portions of the surfaces of the first silicon substrate 10 and the second silicon substrate 20. The first and second conductive regions have first and second activated regions 15a, 25a, at least portions of which are activated. For example, the first and second activated regions 15a, 25a may have hydroxyl groups on their surfaces.

[0128] Furthermore, silanol groups (—Si—OH) may be present on the surfaces of the first and second bonding portions (silicon oxide portions in this example) of the first silicon substrate 10 and the second silicon substrate 20. The first silicon substrate 10 and the second silicon substrate 20 having silanol groups on the surfaces of the first and second bonding portions, which are silicon oxide portions, do not particularly require surface treatment, but may be obtained, if necessary, by the above-mentioned surface treatment that generates silanol groups.

[0129] The organic material is a substituted or unsubstituted hydrocarbon compound having hydrolyzable silyl groups at two terminals. Such a compound may have two or more terminals, and may have hydrolyzable silyl groups at any two or more terminals. Such a compound may be fluorine-substituted, in other words, a fluorine-containing silane compound such as a fluoroalkyl compound having hydrolyzable silyl groups at two terminals or a fluoropolyether group-containing compound.

[0130] The fluorine-containing silane compound is, for example, a compound represented by the following formula (11): [In the formula: R Ｆ２ is -Rf ２ ｐ -R Ｆ ｒ -O ｑ -; Rf ２ is a C optionally substituted by one or more fluorine atoms; １－２０ is an alkylene group; R Ｆ is independently at each occurrence a group represented by the formula: ６ F １２ ) ａ - (OC ５ F １０ ) ｂ - (OC ４ F ８ ) ｃ - (OC ３ R Ｆａ ６ ) ｄ - (OC ２ F ４ ) ｅ -(OCF ２ ) ｆ - (wherein, R Ｆａ are each independently a hydrogen atom, a fluorine atom, or a chlorine atom in each occurrence; a, b, c, d, e, and f are each independently an integer of 0 to 200, the sum of a, b, c, d, e, and f is 1 or more, and the order of the repeating units enclosed in parentheses with a, b, c, d, e, or f is arbitrary in the formula, provided that all R Ｆａis a hydrogen atom or a chlorine atom, at least one of a, b, c, e and f is 1 or more; p is 0 or 1; q is 0 or 1; r is 0 or 1; provided that either p or r is 1; R Ｓｉ are each independently in each occurrence a group represented by the following formula (S1), (S2), (S3), (S4) or (S5): (In the formula: R １１ is independently in each occurrence a hydroxyl group or a hydrolyzable group; R １２ is independently in each occurrence a hydrogen atom or a monovalent organic group; n1 is (SiR １１ ｎ１ R １２ ３－ｎ１ ) units are each independently an integer of 0 to 3; １１ is independently in each occurrence a single bond or a divalent organic group; R １３ is independently in each occurrence a hydrogen atom or a monovalent organic group; t is independently in each occurrence an integer of 2 or greater; R １４ is independently in each occurrence a hydrogen atom, a halogen atom or -X １１ -SiR １１ ｎ１ R １２ ３－ｎ１ and R ａ１ is independently at each occurrence -Z １ -SiR ２１ ｐ１ R ２２ ｑ１ R ２３ ｒ１ and Z １ is independently in each occurrence an oxygen atom or a divalent organic group; R ２１ is independently at each occurrence -Z １’ -SiR ２１’ ｐ１’ R ２２’ ｑ１’ R ２３’ ｒ１’ and R ２２is independently in each occurrence a hydroxyl group or a hydrolyzable group; R ２３ are each independently in each occurrence a hydrogen atom or a monovalent organic group; p1 is each independently in each occurrence an integer of 0 to 3; q1 is each independently in each occurrence an integer of 0 to 3; r1 is each independently in each occurrence an integer of 0 to 3; Z １’ is independently in each occurrence an oxygen atom or a divalent organic group; R ２１’ is independently at each occurrence -Z １” -SiR ２２” ｑ１” R ２３” ｒ１” and R ２２’ is independently in each occurrence a hydroxyl group or a hydrolyzable group; R ２３’ are each independently in each occurrence a hydrogen atom or a monovalent organic group; p1' are each independently in each occurrence an integer of 0 to 3; q1' are each independently in each occurrence an integer of 0 to 3; r1' are each independently in each occurrence an integer of 0 to 3; Z １” is independently in each occurrence an oxygen atom or a divalent organic group; R ２２” is independently in each occurrence a hydroxyl group or a hydrolyzable group; R ２３” are each independently in each occurrence a hydrogen atom or a monovalent organic group; q1" are each independently in each occurrence an integer of 0 to 3; r1" are each independently in each occurrence an integer of 0 to 3; R ｂ１ is independently in each occurrence a hydroxyl group or a hydrolyzable group; R ｃ１ are each independently in each occurrence a hydrogen atom or a monovalent organic group; k1 are each independently in each occurrence an integer from 1 to 3; l1 are each independently in each occurrence an integer from 0 to 3; m1 are each independently in each occurrence an integer from 0 to 3; R ｄ１ is independently at each occurrence -Z ２ -CR３１ ｐ２ R ３２ ｑ２ R ３３ ｒ２ and Z ２ is independently in each occurrence a single bond, an oxygen atom, or a divalent organic group; R ３１ is independently at each occurrence -Z ２’ -CR ３２’ ｑ２’ R ３３’ ｒ２’ and R ３２ is independently at each occurrence -Z ３ -SiR ３４ ｎ２ R ３５ ３－ｎ２ and R ３３ is independently in each occurrence a hydrogen atom, a hydroxyl group, or a monovalent organic group; p2 is independently in each occurrence an integer of 0 to 3; q2 is independently in each occurrence an integer of 0 to 3; r2 is independently in each occurrence an integer of 0 to 3; Z ２’ is independently in each occurrence a single bond, an oxygen atom, or a divalent organic group; R ３２’ is independently at each occurrence -Z ３ -SiR ３４ ｎ２ R ３５ ３－ｎ２ and R ３３’ is independently in each occurrence a hydrogen atom, a hydroxyl group, or a monovalent organic group; q2' is independently in each occurrence an integer of 0 to 3; r2' is independently in each occurrence an integer of 0 to 3; Z ３ is independently in each occurrence a single bond, an oxygen atom, or a divalent organic group; R ３４ is independently in each occurrence a hydroxyl group or a hydrolyzable group; R ３５ is independently in each occurrence a hydrogen atom or a monovalent organic group; n2 is independently in each occurrence an integer of 0 to 3; R ｅ１is independently at each occurrence -Z ３ -SiR ３４ ｎ２ R ３５ ３－ｎ２ and R ｆ１ are each independently in each occurrence a hydrogen atom, a hydroxyl group, or a monovalent organic group; k2 are each independently in each occurrence an integer of 0 to 3; l2 are each independently in each occurrence an integer of 0 to 3; m2 are each independently in each occurrence an integer of 0 to 3; R ｇ１ and R ｈ１ is independently at each occurrence -Z ４ -SiR １１ ｎ１ R １２ ３－ｎ１ , -Z ４ -SiR ａ１ ｋ１ R ｂ１ ｌ１ R ｃ１ ｍ１ , -Z ４ -CR ｄ１ ｋ２ R ｅ１ ｌ２ R ｆ１ ｍ２ and Z ４ are each independently a single bond, an oxygen atom, or a divalent organic group in each occurrence; provided that in formulae (S1), (S2), (S3), (S4), and (S5), there is at least one Si atom to which a hydroxyl group or a hydrolyzable group is bonded; X Ａ are each independently a single bond or a divalent to decavalent organic group; and γ is each independently an integer of 1 to 9.

[0131] The hydrolyzable group means a group that can undergo a hydrolysis reaction, and is preferably —OR ｊ , -OCOR ｊ , —O—N═CR ｊ ２ , -NR ｊ ２ , -NHR ｊ , or halogen. ｊ is a substituted or unsubstituted C１－４ alkyl group, preferably unsubstituted C １－４ It is an alkyl group. １－４ The alkyl group is preferably an ethyl group or a methyl group, more preferably a methyl group.

[0132] The hydrolyzable silyl group may be, in the simplest case, an alkoxysilyl group. The number of alkoxy groups in the alkoxysilyl group is 1 to 3, for example, 3. The number of carbon atoms in the alkoxy group may be, for example, 1 to 4, particularly 2 or less, and preferably 1.

[0133] The unsubstituted silane compound may be, for example, R ｋ ３ Si-(CH ２ ) ｎ３５ -SiR ｋ ３ R ｋ each independently represents a group capable of undergoing a hydrolysis reaction, and preferably each independently represents -OR ｊ , -OCOR ｊ , —O—N═CR ｊ ２ , -NR ｊ ２ , -NHR ｊ , or halogen. ｊ is a substituted or unsubstituted C １－４ alkyl group, preferably unsubstituted C １－４ It is an alkyl group. １－４ The alkyl group is preferably an ethyl group or a methyl group, more preferably a methyl group. n35 is an integer of 1 to 18.

[0134] Unless otherwise specified, the above explanations may apply.

[0135] The organic material is supplied between the first silicon substrate 10 and the second silicon substrate 20 and reacted. The organic material may react with the first and second activated regions 15a and 25a. Specifically, alkenyl groups of the organic material may react with hydrogen atoms of the first and second activated regions 15a and 25a, respectively. Alternatively, the organic material may be supplied between the first and second bonding portions to react hydrolyzable silyl groups of the organic material with silanol groups of the first and second bonding portions (e.g., siloxane bond formation by dealcoholization when the hydrolyzable groups are alkoxy groups). As a result, the first reaction product derived from the organic material chemically bonds to the metals of the first and second conductive regions 15 and 25 and / or Si atoms of the first and second bonding portions. In such a reaction, a by-product such as alcohol is produced, but the number of carbon atoms thereof can be small as described above, and the alcohol can be effectively removed to the outside from between the first silicon substrate 10 and the second silicon substrate 20 through the gaps in the reaction product, thereby reducing the formation of voids due to the by-product.

[0136] The organic material may be applied to the first activated region 15a to react with the first activated region 15a. The surface of the layer formed from the organic material may then be washed with water or a water-containing organic solvent, and the second activated region 25a may then be placed on the layer. This allows hydrolyzable silyl groups present on the surface to be converted to silanols, thereby suppressing the formation of by-products such as hydrolyzable silyl groups or voids derived from the by-products. The organic material may also be applied to the surface of the second activated region 25a, rather than the surface of the first activated region 15a.

[0137] The reaction may be carried out in one step with the organic material sandwiched between the first silicon substrate 10 and the second silicon substrate 20, or may be carried out in two steps by applying the organic material to one of the first silicon substrate 10 or the second silicon substrate 20 to partially promote the reaction, and then placing the other substrate on top of the organic material to further promote the reaction.

[0138] As an example, the reaction when an alkyl compound having trimethoxysilyl groups at two terminals is used is shown below. An example in which the reaction is carried out in two separate steps as described above is also shown below. Note that Cu is used as an example of the first and second conductive regions 15 and 25 below. Furthermore, although only the reaction in the first and second activated regions 15a and 25a is described below, the same reaction as in the first and second activated regions 15a and 25a may also occur in the first and second junctions.

[0139]

[0140]

[0141] In order to obtain higher bonding strength, the organic material is preferably a linear compound having hydrolyzable silyl groups at both ends, but is not limited to this.

[0142] Second Example (Sixth Example) Using Organic Material (iii) In this example, differences from the first example using the organic material (iii) described above will be mainly described, and unless otherwise specified, the same description as in the first example above may apply.

[0143] The organic material is a substituted or unsubstituted hydrocarbon compound having isocyanate groups at two terminals. Such a compound may have two or more terminals, and may have isocyanate groups at any two or more terminals.

[0144] The organic material is supplied between the first silicon substrate 10 and the second silicon substrate 20, and the isocyanate groups of the organic material are reacted with the hydroxyl groups of the first and second activated regions 15a and 25a. As a result, a first reaction product derived from the organic material chemically bonds to the metal atoms of the first and second conductive regions 15 and 25, bonding the first conductive region 15 and the second conductive region 25 together via the reaction product derived from the organic material. Furthermore, the isocyanate groups of the organic material may be reacted with the silanol groups of the first and second bonding portions (forming a urethane bond). As a result, the first reaction product derived from the organic material chemically bonds to the Si atoms of the first and second bonding portions, bonding the first and second bonding portions together via the first reaction product derived from the first organic material. This reaction, which does not produce by-products, fundamentally solves the problem of void formation due to by-products.

[0145] The unsubstituted silane compound is, for example, OCN—(CH ２ ) ｎ３５ n35 is an integer of 1 to 18.

[0146] In one embodiment, the reaction when an alkyl compound having isocyanate groups at two terminals is used is shown below. Note that, below, Cu is described as an example of the first and second conductive regions 15, 25. Also, while only the reaction in the first and second activated regions 15a, 25a is described below, the same reaction as in the first and second activated regions 15a, 25a can also occur in the first and second bonding portions. Note that, in this embodiment, as with an alkyl compound having trimethoxysilyl groups at two terminals, only one isocyanate group may react first, and then the other isocyanate group may react.

[0147]

[0148] In another embodiment, the reaction when a compound having a phosphate group is used is shown below. ３ PO(OH) ２Although an example using Cu is shown, compounds of other structures may be used as long as they have a phosphate group. For example, a compound containing two or more phosphate groups, such as 1,6-hexanediphosphonic acid, may be used. In the case of a compound containing two or more phosphate groups, one phosphate group may react with the first conductive region 15, and another phosphate group may react with the second conductive region 25. Note that, below, Cu is described as an example of the first and second conductive regions 15, 25. Although below, only the reaction in the first and second activated regions 15a, 25a is described, the same reaction as in the first and second activated regions 15a, 25a may also occur in the first and second junctions.

[0149]

[0150] Alternatively, as described below, first the first activation region 15a may react with the compound having a phosphate group, and then the second conductive region 25 may react with the compound having a phosphate group.

[0151]

[0152] Third Example (Seventh Example) Using Organic Material (iii) In this example, differences from the first example using the organic material (iii) described above will be mainly described, and unless otherwise specified, the same description as in the first example can be applied.

[0153] The organic material is a substituted or unsubstituted hydrocarbon compound having acid anhydride groups at two terminals. Such a compound may have two or more terminals, and may have acid anhydride groups at any two or more terminals.

[0154] The organic material is supplied between the first silicon substrate 10 and the second silicon substrate 20, and the acid anhydride groups of the organic material react with the hydroxyl groups of the first and second activated regions 15a and 25a. As a result, a reaction product derived from the organic material chemically bonds to the metal atoms of the first and second activated regions 15a and 25a, bonding the first activated region 15a and the second activated region 25a together via the reaction product derived from the organic material. Furthermore, the acid anhydride groups of the organic material react with the silanol groups of the first and second bonding regions. As a result, the first reaction product derived from the organic material chemically bonds to the Si atoms of the first bonding region and the Si atoms of the second bonding region, bonding the first bonding region and the second bonding region together via the reaction product derived from the organic material. This reaction does not produce by-products, fundamentally eliminating the problem of void formation due to by-products.

[0155] The reaction when an alkyl compound having acid anhydride groups at two terminals is shown below as an example. Note that Cu is described below as an example of the first and second conductive regions 15, 25. Furthermore, although only the reaction in the first and second activated regions 15a, 25a is described below, the same reaction as in the first and second activated regions 15a, 25a can also occur in the first and second junctions.

[0156]

[0157] R represents an alkyl group, for example, —(CH ２ ) ｎ３６ -, and n36 is an integer between 1 and 18. Note that the first activated region 15a may first react with an alkyl compound having an acid anhydride group, and then the second conductive region 25 may react with a compound having an acid anhydride group. Similarly, in the following cases, the compound may react with the first activated region 15a, and then with the second conductive region 25.

[0158] (Eighth Example) In the fifth to seventh examples, the organic material chemically reacts with the first and second conductive regions 15, 25 to connect the first and second conductive regions 15, 25, but the eighth example differs in that part A is present on at least a portion of the surface of the first and second conductive regions 15, 25, and no chemical reaction occurs between the first and second conductive regions 15, 25 and part A. In other words, the first and second conductive regions 15, 25 are not chemically connected via part A. Other than that, the structure is the same as in the fifth example, and part A has the same structure as in the second example.

[0159] The above have described first to third examples in which a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group, an isocyanate group, or an acid anhydride group at two terminal ends is used as the organic material. However, instead of or in addition to the hydrolyzable silyl group, the isocyanate group, or the acid anhydride group, a substituted or unsubstituted hydrocarbon compound having a hydroxyl group, an epoxy group, and / or an amino group may be used. The hydroxyl group, the hydrolyzable silyl group, the isocyanate group, the epoxy group, the amino group, and the acid anhydride group can all function as a group reactive with a silanol group. These reactive groups at at least two terminal ends may be the same or different.

[0160] Example (iv) Using an Organic Material (Example 9) In this example, the differences from the first example using the organic material (iii) described above will be mainly described, and unless otherwise specified, the same description as in the first example above may apply.

[0161] Silsesquioxane is used as the organic material. Silsesquioxane refers to a silicon-containing polymer (polysiloxane) whose main chain is composed of siloxane bonds and whose basic structural unit is a T unit. Silsesquioxane is a (R'SiO １．５ ) ｎ(R' can be any organic group, n is 6 or more), and can have a random structure, a ladder structure, a cage structure (complete cage structure, incomplete cage structure), etc. Examples of when R' is a hydrocarbon group include methyl, ethyl, propyl (n-propyl, i-propyl), butyl (n-butyl, i-butyl, t-butyl, sec-butyl), pentyl (n-pentyl, i-pentyl, neopentyl, cyclopentyl, etc.), hexyl (n-hexyl, i-hexyl, cyclohexyl, etc.), heptyl (n-heptyl, i-heptyl, etc.), octyl (n-octyl, i-octyl, t-octyl, etc.), nonyl (n-nonyl, i-nonyl, etc.), decyl (n-decyl, i-decyl, etc.), cyclohexyl, ... Examples of the alkyl group include acyclic or cyclic aliphatic hydrocarbon groups such as undecyl (n-undecyl, i-undecyl, etc.) and dodecyl (n-dodecyl, i-dodecyl, etc.), acyclic and cyclic alkenyl groups such as vinyl, propenyl, butenyl, pentenyl, hexenyl, cyclohexenyl, cyclohexenylethyl, norbornenylethyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, styrenyl, etc., and aralkyl groups such as benzyl, phenethyl, 2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl, etc., aralkyl groups such as PhCH=CH- group, aryl groups such as phenyl group, tolyl group, or xylyl group, and substituted aryl groups such as 4-aminophenyl group, 4-hydroxyphenyl group, 4-methoxyphenyl group, and 4-vinylphenyl group.

[0162] The organic material is supplied between the first silicon substrate 10 and the second silicon substrate 20, causing the siloxane bond sites of the organic material to react with the hydroxyl groups of the first and second activated regions 15a, 25a. As a result, a first reaction product derived from the organic material chemically bonds to the metal atoms of the first and second conductive regions 15, 25, bonding the first conductive region 15 and the second conductive region 25 together via the first reaction product derived from the organic material. Furthermore, the organic material is supplied between the first and second bonding portions, causing the siloxane bond sites of the organic material to react with the silanol groups of the first and second bonding portions (siloxane bond cleavage and addition). As a result, the reaction product derived from the first organic material chemically bonds to the Si atoms of the first and second bonding portions, bonding the first and second bonding portions together via the reaction product derived from the organic material. Such a reaction does not produce by-products, so the problem of void formation resulting from by-products can be fundamentally resolved.

[0163] Illustratively, T having a complete cage structure ８ Silsesquioxane ((R'SiO １．５ ) ８ The reaction when Cu is used is shown below. In the following, Cu is described as an example of the first and second conductive regions 15, 25. In the following, only the reaction in the first and second activated regions 15a, 25a is described, but the same reaction as the reaction in the first and second activated regions 15a, 25a can also occur in the first and second junctions.

[0164]

[0165] In order to obtain higher bonding strength, the organic material is preferably a cage silsesquioxane having a clear molecular structure, but is not limited to this.

[0166] (Tenth Example) In the ninth example, the organic material chemically reacts with the first and second conductive regions 15, 25 to connect the first and second conductive regions 15, 25, but the tenth example differs in that part A is present on at least a portion of the surface of the first and second conductive regions 15, 25, and no chemical reaction occurs between the first and second conductive regions 15, 25 and part A. In other words, the first and second conductive regions 15, 25 are not chemically connected via part A. The rest of the configuration is the same as in the ninth example, and part A has the same configuration as in the second example.

[0167] Although the above describes an example in which silsesquioxane is used as the organic material, a silsesquioxane derivative may also be used. The silsesquioxane derivative may be any compound derived from silsesquioxane, and may have any substituent, modifying group, functional group, etc.

[0168] (Reaction conditions for organic materials) The reaction conditions may vary depending on the organic material used, but the predetermined temperature may be, for example, 200°C or less, particularly 120°C or less, more particularly 80°C or less, or may simply be room temperature (typically 10°C or more and 40°C or less). According to this embodiment, bonding can be performed at such a relatively low temperature, so that bonding misalignment caused by thermal expansion of the first and second silicon substrates 10, 20 can be reduced, and bonding can be performed with high precision. The pressure (absolute pressure, the same applies to other pressure values ​​in this specification) is, for example, 10 －８ Pa or more, especially 10 －５ Pa or more, more particularly 10 －１ Pa or more, more particularly 10 ２ The pressure may be at least 1.01×10 Pa, and may be conveniently normal pressure (typically about 1.01×10 ５ When a reduced pressure is applied, for example, 10 ５ Pa or less, particularly 10 ４ Pa or less, more particularly 10 ３ Pa or less.

[0169] By undergoing the above manufacturing method, a stacked body 40 is formed, which has a first silicon substrate 10, a second silicon substrate 20, and an adhesive layer 30 between the first silicon substrate 10 and the second silicon substrate 20. In other words, the stacked body 40 has: a first silicon substrate 10 having a first conductive region 15 on at least a part of its surface; a second silicon substrate 20 located on the side having the first conductive region 15; and an adhesive layer 30 located between the first silicon substrate 10 and the second silicon substrate 20, which bonds the side of the first silicon substrate 10 having the first conductive region 15 to the second silicon substrate 20, and has conductivity between the first silicon substrate 10 and the second silicon substrate 20.

[0170] The adhesive layer 30 may consist of two or more layers.

[0171] Preferably, the conductivity measured at the adhesive layer 30 disposed on the first silicon substrate 10 is 1.0×10 －２ ~5.0 x 10 ２ pA, more preferably in the range of 1.0 x 10 －１ ~1.9 x 10 ２ The conductivity is in the range of pA. The conductivity is a value measured using an SSRM.

[0172] Preferably, the resistivity is 1.5×10 －８ ~2.0 x 10 ５ Ω·m, more preferably 1.6×10 －８ ~1.6 x 10 ４The resistivity is in the range of Ω·m. The resistivity is a value measured as follows. First, two first silicon substrates 10 are prepared. The conductivity (average current value) of the first first silicon substrate 10 is measured, and the resistance value R(b) [Ω] of the first silicon substrate 10 is calculated based on the equation: voltage V [V] = current I [pA] × resistance R [Ω]. After performing surface treatment as necessary on the second first silicon substrate 10, a film of an organic material, which is the raw material for the adhesive layer 30, is formed on the first silicon substrate 10 to form a sample having a film formed on the first silicon substrate 10. The conductivity of the sample is measured, and the resistance value R(all) [Ω] of the sample is calculated. Since R(all) = resistance value R(a) + R(b) of the film-formed portion, the value of R(a) is obtained. Then, R(a) [Ω] = resistivity of sample [Ω·m] × film thickness of sample [m] / effective area of ​​probe [m ２ The resistivity of the sample is determined based on the following equation: The conductivity is measured using an SSRM.

[0173] 2 is a cross-sectional view schematically illustrating a portion of a laminate 40A according to a second embodiment. While the first embodiment includes an adhesive layer 30 between the first conductive region 15 and the second conductive region 25, the second embodiment differs in that an adhesive layer 30A is provided between the first conductive region 15 and the second conductive region 25. The adhesive layer 30A has a first adhesive portion 31A located on the first conductive region 15 and a second adhesive portion 32A located on the second conductive region 25, and at least a portion of the second conductive region 25 includes a second activation region 25a. This difference will be mainly described below, and unless otherwise noted, the laminate has the same configuration as described above in other respects.

[0174] (Adhesive Layer 30A) As shown in FIG. 2, the adhesive layer 30A has a first adhesive portion 31A and a second adhesive portion 32A provided on the second silicon substrate 20 and chemically bonded to the first adhesive portion 31A. The first adhesive portion 31A and the second adhesive portion 32A are bonded by a reaction. During the chemical bonding reaction, heating and / or pressure or pressure reduction are performed as necessary. The conditions for heating, pressure reduction, and pressure reduction are the same as those in the first embodiment. The physical properties of the adhesive layer 30A are the same as those of the adhesive layer 30 in the first embodiment.

[0175] The thickness of the adhesive layer 30A can be extremely thin. For example, the thickness of the adhesive layer 30A is 10 nm or less, and may be particularly 8 nm or less, 5 nm or less, 3 nm or less, or 1.5 nm or less. The lower limit of the thickness of the adhesive layer 30A is not particularly limited, but may be, for example, 1 nm or more. The thickness can be measured in the same manner as in the first embodiment.

[0176] The first adhesive portion 31A includes a first reaction product derived from a first organic material capable of reacting with the first activated region 15a. That is, the composition of the first reaction product depends on the structure of the first organic material. The first adhesive portion 31A can be obtained by applying the first organic material to the first activated region 15a and, if necessary, the first bonding portion, and then drying the applied material. The drying can be performed in the same manner as in the first embodiment.

[0177] The second adhesive portion 32A includes a second reaction product derived from a second organic material capable of reacting with the second activation region 25a. That is, the composition of the second reaction product depends on the structure of the second organic material. The second adhesive portion 32A can be obtained by applying the second organic material to the second activation region 25a and, if necessary, the second bonding portion, and then drying the applied material. The drying can be performed in the same manner as in the first embodiment.

[0178] That is, the second silicon substrate 20 has a second conductive region 25 on at least a portion of its surface, and the adhesive layer 30A is provided on a second activated region 25a that is provided by activating at least a portion of the surface of the second silicon substrate 20 facing the second conductive region 25, and contains a second reaction product derived from a second organic material.

[0179] For convenience, the adhesive portions are referred to as the first adhesive portion 31A and the second adhesive portion 32A, but they may not form an interface or may be mixed. Even if an interface is formed, the interface may not be uniform and may have irregularities.

[0180] (First and Second Organic Materials) The first organic material has a functional group at one end that reacts with the first conductive region 15 or the first junction, and a functional group at the other end that reacts with the second organic material. The second organic material has a functional group at one end that reacts with the second conductive region 25 or the second junction, and a functional group at the other end that reacts with the first organic material. This bonds the first silicon substrate 10 and the second silicon substrate 20. Note that only some of these functional groups may react. Note that, although the above describes a case where one organic material has two functional groups, the organic material may also have three or more functional groups.

[0181] The first organic material and the second organic material may each be used as a composition, and the composition has the same configuration as in the first embodiment.

[0182] The specific aspects of the method for supplying and bonding the first and second organic materials (or compositions containing the first and second organic materials) may be selected appropriately depending on the organic materials used. Generally, after the first and second organic materials are supplied, the first silicon substrate 10 and the second silicon substrate 20 may be maintained under predetermined reaction conditions (particularly, a predetermined temperature) with the first and second organic materials interposed between them, thereby allowing the reaction to proceed.

[0183] More specifically, for example, a first organic material (which may be a composition) is applied (e.g., by coating, spraying, printing, etc.) to the surface of the first silicon substrate 10 on the side having the first conductive region 15 (the surface having at least a portion of the first activated region 15a). Similarly, a second organic material (which may be a composition) is applied to the surface of the second silicon substrate 20 on the side having the second conductive region 25 (the surface having at least a portion of the second activated region 25a). Thereafter, washing and / or drying may be performed as necessary. The washing and drying may be similar to those described above, and when a fluorine-containing organic material is used, pre-washing using a fluorine-based solvent may be performed.

[0184] Thereafter, the first silicon substrate 10 and the second silicon substrate 20 are aligned so that the first conductive region 15 and the second conductive region 25 face each other, and the first silicon substrate 10 and the second silicon substrate 20 are brought into close contact with each other with the first organic material interposed between the first conductive region 15 and the second conductive region 25. The first silicon substrate 10 and the second silicon substrate 20 that have been brought into close contact with each other are maintained under predetermined reaction conditions (particularly, a predetermined temperature) to allow the reaction to proceed. Thereafter, an annealing treatment may be performed as necessary.

[0185] The properties of the first and second organic materials can be the same as those of the first organic material in the first embodiment.

[0186] The first and second organic materials may contain at least one selected from the group consisting of (v) to (vi) below. The organic materials may be composed of a single compound or a combination of two or more compounds. In the following description, the first activated region 15a and the second activated region 25a are described as a pair, and the first bonding portion and the second bonding portion are described as a pair, but this combination is not limiting. For example, the reaction product formed from the first and second organic materials may connect the first activated region 15a and the second bonding portion, or may bond the first bonding portion and the second activated region 25a. (v) A combination of a hydrolyzable hydrosilane or a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and a hydrosilyl group at the other end, and a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and an alkenyl group at the other end. (vi) Substituted or unsubstituted hydrocarbon compounds having a hydrolyzable silyl group at one end and an alkyl group at the other end.

[0187] The details are described below.

[0188] Example of using an organic material (v) (11th example) In this example, the differences from the first example using an organic material (iii) described above will be mainly described, and unless otherwise specified, the same description as in the first example above may apply.

[0189] As the organic material, a first organic material and a second organic material are used in combination.

[0190] The first organic material may be a hydrolyzable hydrosilane, or a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and a hydrosilyl group at the other end, or a mixture thereof, as the case may be. The hydrolyzable hydrosilane may be one having H and one or more hydrolyzable groups on one Si. The substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and a hydrosilyl group at the other end may have two or more end portions, and may have a hydrolyzable silyl group at any one or more end portions and a hydrosilyl group at any one or more end portions. The substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and a hydrosilyl group at the other end may be similar to the substituted or unsubstituted hydrocarbon compound having hydrolyzable silyl groups at two end portions described in detail in (iii) above, except for having a hydrosilyl group at the other end portion.

[0191] The second organic material is a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and an alkenyl group at the other end. Such a compound may have two or more end portions, and may have a hydrolyzable silyl group at any one or more end portions and an alkenyl group at any one or more end portions. The substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and an alkenyl group at the other end may be similar to the substituted or unsubstituted hydrocarbon compound having hydrolyzable silyl groups at two end portions described in detail in (iii) above, except for the presence of an alkenyl group at the other end portion.

[0192] First, a first organic material is supplied to the first silicon substrate 10 and reacted with the hydroxyl groups in the first activated region 15a. The first organic material is also supplied to the second silicon substrate 20 and reacted with the hydroxyl groups in the second activated region 25a. The hydrolyzable silyl groups of the first organic material may be reacted with the silanol groups in the first bonding portion (for example, when the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization), or the hydrolyzable silyl groups of the second organic material may be reacted with the silanol groups in the second bonding portion (for example, when the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization).

[0193] Then, the first conductive region 15 and the second conductive region 25 are arranged so that they face each other, with an intermediate derived from the first organic material and an intermediate derived from the second organic material positioned between them, and these intermediates are reacted (hydrosilylated). As a result, reaction products derived from the first organic material and the second organic material react with metal atoms in the first and second conductive regions 15 and 25, bonding the reaction products derived from the first and second organic materials to the first and second conductive regions 15 and 25. Furthermore, the first organic material and the second organic material chemically bond to Si atoms in the first and second bonding portions, thereby bonding the first and second bonding portions with the reaction products derived from the first and second organic materials. Although alcohol is generated as a by-product in the reaction, its carbon number can be small as described above and can be effectively removed before the first silicon substrate 10 and the second silicon substrate 20 are arranged opposite each other, thereby reducing the formation of voids due to the by-products.

[0194] For example, the first organic material may be R ｋ ３ Si-(CH ２ ) ｎ３７ -CH=CH ２ and SiHR as the second organic material. ｋ ３ can be used. ｋ each independently represents a group capable of undergoing a hydrolysis reaction, and specifically has the same meaning as above. n37 is an integer of 0 to 18, for example, 0.

[0195] Specifically, the reaction when vinyltrimethoxysilane is used as the first organic material and trimethoxyhydrosilane is used as the second organic material is shown below. Note that, below, Cu is described as an example of the first and second conductive regions 15, 25. Also, below, only the reaction in the first and second activated regions 15a, 25a is described, but the same reaction as the reaction in the first and second activated regions 15a, 25a can also occur in the first and second bonding portions.

[0196]

[0197] (Twelfth Example) In the eleventh example, the first organic material reacts with the first conductive region 15, the second organic material reacts with the second conductive region 25, and the reaction between the first organic material and the second organic material connects the first conductive region 15 and the second conductive region 25. However, the twelfth example differs in that part A is present on at least a portion of the surface of the first and second conductive regions 15, 25, and no chemical reaction occurs between the first and second conductive regions 15, 25 and part A. In other words, the first and second conductive regions 15, 25 are not chemically connected via part A. Other than that, the configuration is the same as the eleventh example.

[0198] Specifically, when vinyltrimethoxysilane is used as the first organic material and trimethoxyhydrosilane is used as the second organic material, the first organic material reacts with the Si atoms of the first bonding portion, and the second organic compound bonds to the Si atoms of the second bonding portion, and then the first bonding portion and the second bonding portion can be bonded together by a reaction product derived from the first organic material and the second organic material.

[0199] Portion A exists between the metal atoms of the first conductive region 15 and the metal atoms of the second conductive region 25. Portion A is located on at least a portion of the surface between the first and second conductive regions 15, 25. Portion A is unreacted with the metal atoms of the first conductive region 15 and the metal atoms of the second conductive region 25. Note that the entire surfaces of the first conductive region 15 and the second conductive region 25 may have portion A, or only a portion may have portion A, with the other portions not having portion A. Portion A has the same configuration as described above.

[0200] Example (vi) Using an organic material (13th example) In this example, the differences from the first example (iii) using an organic material described above will be mainly described, and unless otherwise specified, the same description as in the first example above may apply.

[0201] The first and second organic materials each use a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and an alkyl group at the other end. Such a compound may have two or more end portions, and may have a hydrolyzable silyl group at any one or more end portions and an alkyl group at any one or more end portions. The substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and an alkyl group at the other end may be similar to the substituted or unsubstituted hydrocarbon compound having hydrolyzable silyl groups at two end portions detailed in (iii) above, except for the alkyl group at the other end portion. The second organic material may have the same or different structure as the first organic material.

[0202] A first organic material is supplied to the first silicon substrate 10 and reacted with the hydroxyl groups in the first activated region 15a. Also, the first organic material is supplied to the second silicon substrate 20 and reacted with the hydroxyl groups in the second activated region 25a. The first organic material may be supplied to the first bonding portion to cause the hydrolyzable silyl groups of the first organic material to react with the silanol groups in the first bonding portion (for example, when the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization). Alternatively, a second organic material may be supplied to the second bonding portion to cause the hydrolyzable silyl groups of the second organic material to react with the silanol groups in the second bonding portion (for example, when the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization).

[0203] Then, the first conductive region 15 and the second conductive region 25 are arranged so that they face each other, and intermediates derived from the first organic material and intermediates derived from the second organic material are positioned between them, and these intermediates are reacted (radical reaction). At this time, the intermediates derived from the first organic material and intermediates derived from the second organic material present between the first and second bonding portions are also reacted in the same manner. The reaction (radical reaction) between the intermediates may be carried out, for example, by ultraviolet irradiation, ion beam, weak plasma, etc. As a result, the reaction products derived from the first organic material and the second organic material react with metal atoms in the first and second conductive regions 15, 25 and / or Si atoms in the first and second bonding portions, bonding the reaction products derived from the first and second organic materials to the first and second conductive regions 15, 25 and / or the first and second bonding portions. Although alcohol is produced as a by-product in this reaction, the number of carbon atoms thereof can be small as described above, and it can be effectively removed before the first silicon substrate 10 and the second silicon substrate 20 are arranged opposite each other, thereby reducing the formation of voids resulting from the by-product.

[0204] For example, the first organic material and the second organic material may be R ｋ ３ Si(CH ２ ) ｎ３８ H can be used. ｋ each independently represents a group capable of undergoing a hydrolysis reaction, and specifically has the same meaning as above. n38 is an integer of 2 to 18, for example, 0.

[0205] Specifically, the reaction when ethyltrimethoxysilane is used as the first and second organic materials is shown below. Note that, below, Cu is described as an example of the first and second conductive regions 15, 25. Also, below, only the reaction in the first and second activated regions 15a, 25a is described, but the same reaction as the reaction in the first and second activated regions 15a, 25a can also occur in the first and second junctions.

[0206]

[0207] By undergoing the above manufacturing method, a laminate 40A is formed having a first silicon substrate 10, a second silicon substrate 20, and an adhesive layer 30A between the first silicon substrate 10 and the second silicon substrate 20, and the adhesive layer 30A has a first adhesive portion 31A and a second adhesive portion 32A.

[0208] By undergoing the above manufacturing method, a stacked body 40 is formed, which includes a first silicon substrate 10, a second silicon substrate 20, and an adhesive layer 30A between the first silicon substrate 10 and the second silicon substrate 20. In other words, the stacked body 40A includes: a first silicon substrate 10 having a first conductive region 15 on at least a portion of its surface; a second silicon substrate 20 located on the side having the first conductive region 15 and having a second conductive region 25 on at least a portion of its surface; and an adhesive layer 30A located between the first silicon substrate 10 and the second silicon substrate 20 and bonding the surface of the first silicon substrate 10 having the first conductive region 15 to the second conductive region 25 of the second silicon substrate 20, wherein the adhesive layer 30A includes a reaction product between a first adhesive portion 31A located on the first conductive region 15 and a second adhesive portion 32A located on the first conductive region 15, and has conductivity between the first silicon substrate 10 and the second silicon substrate 20.

[0209] The physical properties of the laminate 40A are similar to those of the laminate 40 of the first embodiment.

[0210] (14th Example) In the 13th example, the first organic material reacts with the first conductive region 15, and the second organic material reacts with the second conductive region 25, causing a chemical reaction between the first and second conductive regions 15, 25, thereby connecting the first and second conductive regions 15, 25. However, the 14th example differs in that part A is present on at least a portion of the surface of the first and second conductive regions 15, 25, and no chemical reaction occurs between the first and second conductive regions 15, 25 and part A. In other words, the first and second conductive regions 15, 25 are not chemically connected via part A. The rest of the configuration is the same as in the 13th example, and part A has the same configuration as in the second example.

[0211] (Modification) FIG. 3 is a cross-sectional view schematically illustrating a portion of a laminate 40B according to a modification. Unlike the second embodiment, the modification has a first adhesive portion 31B on the first conductive region 15, a second adhesive portion 32B on the second conductive region 25, and a third adhesive portion 33B between the first adhesive portion 31B and the second adhesive portion 32B. The first adhesive portion 31B and the third adhesive portion 33B, and the second adhesive portion 32B and the third adhesive portion 33B are bonded together. That is, the adhesive layer 30B is composed of three layers: the first adhesive portion 31B, the third adhesive portion 33B, and the second adhesive portion 32B. This difference in configuration will be described below. The remaining configuration is the same as that of the first embodiment, and therefore, a description thereof will be omitted.

[0212] (Adhesive Layer 30B) The adhesive layer 30B has a first adhesive portion 31B, a third adhesive portion 33B, and a second adhesive portion 32B, in that order. The first adhesive portion 31B is provided on the first silicon substrate 10, and the second adhesive portion 32B is provided on the second silicon substrate 20. The third adhesive portion 33B can react with the first adhesive portion 31B at one end and with the second adhesive portion 32B at the other end. That is, the third adhesive portion 33 can react as a connecting portion connecting the first adhesive portion 31B and the second adhesive portion 32B. The above reaction is carried out under heating and / or pressure or reduced pressure as necessary. The conditions for heating, pressure, and reduced pressure are the same as those in the first embodiment.

[0213] The thickness of the adhesive layer 30B can be extremely thin. The thickness of the adhesive layer 30B is, for example, 10 nm or less, and may be particularly 8 nm or less, 5 nm or less, 3 nm or less, or 1.5 nm or less. The lower limit of the thickness of the adhesive layer 30B is not particularly limited, but may be, for example, 1 nm or more. The thickness can be measured in the same manner as in the first embodiment.

[0214] The first adhesive portion 31B includes a first reaction product derived from a first organic material capable of reacting with the first activated region 15a. That is, the composition of the first reaction product depends on the structure of the first organic material. The first adhesive portion 31B can be obtained by applying the first organic material to the first activated region 15a and, if necessary, the first bonding portion, and then drying the applied material. The drying can be performed in the same manner as in the first embodiment.

[0215] The second adhesive portion 32B includes a second reaction product derived from a second organic material capable of reacting with the second activation region 25a. That is, the composition of the second reaction product depends on the structure of the second organic material. The second adhesive portion 32B can be obtained by applying the second organic material to the second activation region 52a and, if necessary, the second bonding portion, and then drying the applied material. The drying can be performed in the same manner as in the first embodiment.

[0216] The third adhesive portion 33B includes a reaction product derived from a third organic material capable of reacting with the first organic material and the second organic material. The third adhesive portion 33B can be obtained by applying the first reaction product and, if necessary, the third organic material to the first bonding portion, followed by drying. The drying can be performed in the same manner as in the first embodiment.

[0217] For convenience, the adhesive portions are referred to as the first adhesive portion 31A, the second adhesive portion 32A, and the third adhesive portion 33B, but these adhesive portions may not form an interface or may be mixed. Even if an interface is formed, the interface may not be uniform and may have irregularities.

[0218] (First to Third Organic Materials) The first organic material has a functional group at one end that reacts with the first conductive region 15B or the first junction, and a functional group at the other end that reacts with the third organic material. The second organic material has a functional group at one end that reacts with the second conductive region 25B or the second junction, and a functional group at the other end that reacts with the third organic material. The third organic material has a functional group at one end that can react with the first organic material, and a functional group at the other end that can react with the second organic material. This bonds the first silicon substrate 10 and the second silicon substrate 20. Note that only some of these functional groups may react. Note that although the above describes a case where one organic material has two functional groups, the organic material may also have three or more functional groups.

[0219] The first to third organic materials may be used as compositions, each of which has the same structure as that of the first embodiment.

[0220] The specific aspects of the supply method and bonding method for the first to third organic materials (or compositions containing the first to third organic materials) may be selected appropriately depending on the organic materials used. Generally, after the first to third organic materials are supplied, the reaction may proceed by maintaining the first silicon substrate 10 and the second silicon substrate 20 under predetermined reaction conditions (particularly, a predetermined temperature) with the organic materials interposed between them.

[0221] More specifically, for example, a first organic material (which may be a composition) is applied (e.g., by coating, spraying, printing, etc.) to the surface of the first silicon substrate 10 on the side having the first conductive region 15 (the surface having at least a portion of the first activated region 15a). Similarly, a second organic material (which may be a composition) is applied to the surface of the second silicon substrate on the side having the second conductive region 25 (the surface having at least a portion of the second activated region 25a). Thereafter, washing and / or drying may be performed as necessary. The washing and drying may be similar to those described above, and when a fluorine-containing organic material is used, pre-washing using a fluorine-based solvent may be performed.

[0222] Then, a third organic material (which may be a composition) is applied (for example, by coating, spraying, printing, etc.) to the region derived from the first organic material. Washing and / or drying may then be performed as necessary. The washing and drying may be the same as those described above. When a fluorine-containing organic material is used, preliminary washing with a fluorine-based solvent may be performed.

[0223] Then, a region derived from the second organic material is provided on the region derived from the third organic material. Specifically, the first silicon substrate 10 and the second silicon substrate 20 are aligned so that the first conductive region 15 and the second conductive region 25 face each other, and the first silicon substrate 10 and the second silicon substrate 20 are brought into close contact with each other with the first to third organic materials interposed between the first conductive region 15 and the second conductive region 25. The tightly contacted first silicon substrate 10 and the second silicon substrate 20 are maintained under predetermined reaction conditions (particularly, a predetermined temperature) to allow the reaction to proceed. An annealing treatment may then be performed as necessary.

[0224] The properties of the first to third organic materials can be the same as those of the first organic material in the first embodiment.

[0225] The properties of the first to third organic materials can be the same as those of the first organic material in the first embodiment.

[0226] Each organic material is described below. Note that the following description will focus on differences from the first example using the organic material (iii) described above, and unless otherwise specified, the same description as in the first example above can be applied.

[0227] The following materials can be used as the organic material: (vii) a substituted or unsubstituted hydrocarbon compound having a hydrolyzable silyl group at one end and a reactive functional group at the other end.

[0228] Exemplary embodiments are described in detail below.

[0229] Example (vii) Using an organic material (15th example) In this example, the differences from the first example (iii) using an organic material described above will be mainly described, and unless otherwise specified, the same description as in the first example above may apply.

[0230] The first and second organic materials are substituted or unsubstituted hydrocarbon compounds having a hydrolyzable silyl group at one end and a reactive functional group at the other end. Such compounds may have two or more end portions, and may have a hydrolyzable silyl group at any one or more end portions and a reactive functional group at any one or more end portions. The first and second organic materials may be similar to the substituted or unsubstituted hydrocarbon compounds having hydrolyzable silyl groups at two end portions described in detail in (iii) above, except for the reactive functional group at the other end portion. The first and second organic materials may have the same or different structures apart from the end portions.

[0231] The reactive functional group may typically be at least one selected from the group consisting of an isocyanate group, an amino group, a hydroxyl group, a thiol group (also called a sulfanyl group), and the like, but is not limited to these.

[0232] In this embodiment, a third organic material is further used. The third organic material has two groups capable of bonding to the reactive functional groups of the first and second organic materials. The third organic material may have two (or more) of the bondable groups, and more specifically, may have the bondable groups at any two (or more) of its terminal ends. The number of carbon atoms in the portion of the third organic material excluding the bondable groups is not particularly limited, but may be, for example, 1 to 20, and particularly 5 or less. The portion excluding the bondable groups may be linear, branched, or cyclic. Typically, the third organic material may be a linear organic compound having the bondable groups at both terminal ends, but is not limited thereto.

[0233] The bondable group is selected depending on the reactive functional group. Examples of combinations of reactive functional groups and groups bondable thereto are shown below, but are not limited to these. The reactive functional group may be of one type or two or more types, and the bondable group may be of one type or two or more types as long as it can be bonded to the reactive functional group.

[0234]

[0235] The reactive functional groups and bondable groups may be reactive with hydroxyl groups and / or hydrogen atoms, and hydrosilyl groups and / or silanol groups, or may not substantially react with them. When all of the reactive functional groups and bondable groups are reactive with hydroxyl groups and / or hydrogen atoms, and hydrosilyl groups and / or silanol groups, it can be understood that two types of organic materials (iii) are used, but this need not be taken into consideration when using an organic material (vii).

[0236] For example, the first organic material and the second organic material may be R ｋ ３ Si-(CH ２ )ｎ３１ When —NCO is used, the third organic material is, for example, H ２ N-(CH ２ ) ｎ３２ -NH ２ , HS-(CH ２ ) ｎ３２ -SH and HO-(CH ２ ) ｎ３２ As the first organic material and the second organic material, at least one of R ｋ ３ Si-(CH ２ ) ｎ３３ -NH ２ When the third organic material is OCN—(CH ２ ) ｎ３４ -NCO can be used. n31 is an integer of 1 to 18, for example, 1. n32 is independently an integer of 1 to 18, for example, 2. n33 is an integer of 1 to 18, for example, 1. n34 is an integer of 1 to 18, for example, 2.

[0237] R ｋ means a group capable of undergoing a hydrolysis reaction, and preferably each independently represents -OR ｊ , -OCOR ｊ , —O—N═CR ｊ ２ , -NR ｊ ２ , -NHR ｊ , or halogen. ｊ is a substituted or unsubstituted C １－４ alkyl group, preferably unsubstituted C １－４ It is an alkyl group. １－４ The alkyl group is preferably an ethyl group or a methyl group, more preferably a methyl group.

[0238] Specifically, the reaction when isocyanatomethyltrimethoxysilane is used as the first organic material and the second organic material, and ethylenediamine (1,2-diaminoethane) is used as the third organic material is shown below. In the following schematic diagram, the upper row conveniently shows only the bonding portion of one of the substrates, and the first method corresponds to the scheme indicated by the arrows pointing from the left side of the upper row to the lower row. The second method corresponds to the scheme indicated by the arrows pointing from the left side of the upper row to the center and from the center to the lower row. The third method corresponds to the scheme indicated by the arrows pointing from the left side of the upper row to the center, the arrows pointing from the center to the right side of the upper row, and the arrows pointing from the right side to the lower row (the same applies below). Note that Cu is used below as an example of the first and second conductive regions 15 and 25. In the following, only the reactions in the first and second activation regions 15a and 25a are described, but the same reactions as those in the first and second activation regions 15a and 25a may also occur in the first and second bonding portions 23.

[0239]

[0240] Specifically, the reaction when isocyanatomethyltrimethoxysilane is used as the first and second organic materials and ethylene glycol (1,2-ethanediol) is used as the third organic material is shown below.

[0241]

[0242] Specifically, the reaction when aminomethyltrimethoxysilane is used as the first and second organic materials and ethylene diisocyanate (1,2-ethane diisocyanate) is used as the third organic material is shown below.

[0243]

[0244] Any appropriate method (scheme) may be applied as a method for bonding the first silicon substrate 10 and the second silicon substrate 20 using the first to third organic materials. Three methods are shown below, but the present invention is not limited to these.

[0245] (First Method) In the first method, the first and second organic materials and the third organic material are mixed (e.g., immediately before use), and the resulting mixture is supplied between the first silicon substrate 10 and the second silicon substrate 20, where the hydrolyzable silyl groups of the first and second organic materials react with the hydroxyl groups of the first and second activated regions 15a, 25a. This chemically bonds the first organic material to the metal atoms of the first conductive region 15, and the second organic material to the metal atoms of the second conductive region 25. Furthermore, the reactive functional groups of the first and second organic materials react with the bondable groups of the third organic material to bond them. This bonds the first organic material chemically bonded to the metal atoms of the first conductive region 15 and the second organic material chemically bonded to the metal atoms of the second conductive region 25 via the third organic material.

[0246] Furthermore, the hydrolyzable silyl groups of the first and second organic materials are reacted with the silanol groups of the first and second bonding portions (for example, when the hydrolyzable groups are alkoxy groups, siloxane bonds are formed by dealcoholization). This chemically bonds the first organic material to the Si atoms of the first bonding portion, and the second organic material to the Si atoms of the second bonding portion. Furthermore, the reactive functional groups of the first and second organic materials are reacted with and bonded to the bondable groups of the third organic material. This bonds the first organic material chemically bonded to the Si atoms of the first bonding portion and the second organic material chemically bonded to the Si atoms of the second bonding portion via the third organic material.

[0247] The reaction between the hydrolyzable silyl groups of the first organic material and the first activated region 15a or the first bonding portion, the reaction between the hydrolyzable silyl groups of the first organic material and the silanol groups of the second activated region 25a or the second bonding portion, and the reaction between the reactive functional groups of the first and second organic materials and the bondable groups of the third organic material can occur at any timing, for example, either reaction can proceed first, or they can proceed simultaneously. As a result, the first silicon substrate 10 and the second silicon substrate 20 are bonded together by a reaction product derived from the first to third organic materials. While alcohols may be generated as by-products, their carbon numbers may be small as described above, and they can be effectively removed from between the first silicon substrate 10 and the second silicon substrate 20 to the outside through gaps in the reaction products, thereby reducing the formation of voids due to the by-products.

[0248] (Second Method) In the second method, a first organic material is supplied to the first activated region 15a, and the hydrolyzable silyl groups of the first organic material are reacted with the hydroxyl groups of the first activated region 15a (for example, if the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization). A second organic material is supplied to the second activated region 25a, and the hydrolyzable silyl groups of the second organic material are reacted with the hydroxyl groups of the second activated region 25a (for example, if the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization). (The first organic material supplied to the first activated region 15a and the second organic material supplied to the second activated region 25a may be the same or different.) As a result, the first organic material chemically bonds to the metal atoms of the first conductive region 15, and the second organic material chemically bonds to the metal atoms of the second conductive region 25.

[0249] Then, the first conductive region 15 and the second conductive region 25 are arranged so that they face each other, and an intermediate derived from the first and second organic materials is positioned between them together with a third organic material, and the reactive functional groups of the first and second organic materials react with and bond to the bondable groups of the third organic material, thereby bonding the first organic material chemically bonded to the metal atoms of the first conductive region 15 and the second organic material chemically bonded to the metal atoms of the second conductive region 25 via the third organic material.

[0250] Furthermore, a first organic material is supplied to the first bonding portion, causing the hydrolyzable silyl groups of the first organic material to react with the silanol groups of the first bonding portion (for example, if the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization), and a second organic material is supplied to the second bonding portion, causing the hydrolyzable silyl groups of the second organic material to react with the silanol groups of the second bonding portion (for example, if the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization). (The first organic material supplied to the first bonding portion and the second organic material supplied to the second bonding portion may be the same or different.) As a result, the first organic material chemically bonds to the Si atoms of the first bonding portion, and the second organic material chemically bonds to the Si atoms of the second bonding portion.

[0251] Then, the first and second bonding portions are arranged so as to face each other, and an intermediate derived from the first and second organic materials is positioned between them together with a third organic material, and the reactive functional groups of the first and second organic materials are reacted with and bonded to the bondable groups of the third organic material, thereby bonding the first organic material chemically bonded to the Si atoms of the first bonding portion and the second organic material chemically bonded to the Si atoms of the second bonding portion via the third organic material.

[0252] As a result, the first conductive region 15 and the second conductive region 25, and the first bonding portion and the second bonding portion are bonded by reaction products derived from the first to third organic materials. Although alcohol, for example, may be generated as a by-product, the number of carbon atoms thereof may be small as described above, and it can be effectively removed before the first silicon substrate 10 and the second silicon substrate 20 are disposed opposite each other, thereby reducing the formation of voids resulting from the by-products.

[0253] (Third Method) In the third method, a first organic material is supplied to the first activated region 15a, and the hydrolyzable silyl groups of the first organic material react with the hydroxyl groups of the first activated region 15a (for example, if the hydrolyzable groups are alkoxy groups, a siloxane bond is formed by dealcoholization). A second organic material is supplied to the second activated region 25a, and the hydrolyzable silyl groups of the second organic material react with the hydroxyl groups of the second activated region 25a (for example, if the hydrolyzable groups are alkoxy groups, a siloxane bond is formed by dealcoholization). (The first organic material supplied to the first activated region 15a and the second organic material supplied to the second activated region 25a may be the same or different.) As a result, the first organic material chemically bonds to the metal atoms of the first conductive region 15 (intermediate X1), and the second organic material chemically bonds to the metal atoms of the second conductive region 25 (intermediate X2). Then, intermediate X1 is conveniently selected as one of intermediates X1 and X2, and a third organic material is supplied to intermediate X1, causing the reactive functional groups of the first organic material to react with the bondable groups of the third organic material to bond (intermediate Y). Intermediate Y thus obtained and intermediate X2 obtained above are then arranged facing each other, and the reactive functional groups of intermediate X2 (second organic material) react with the bondable groups of intermediate Y (first organic material + third organic material) to bond. This results in the first organic material chemically bonded to the metal atoms of first conductive region 15 and the second organic material chemically bonded to the metal atoms of second conductive region 25 being bonded via the third organic material.

[0254] Furthermore, a first organic material is supplied to the first bonding portion, causing the hydrolyzable silyl groups of the first organic material to react with the silanol groups of the first bonding portion (for example, if the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization), and a second organic material is supplied to the second bonding portion, causing the hydrolyzable silyl groups of the second organic material to react with the silanol groups of the second bonding portion (for example, if the hydrolyzable group is an alkoxy group, a siloxane bond is formed by dealcoholization). (The first organic material supplied to the first bonding portion and the second organic material supplied to the second bonding portion may be the same or different.) As a result, the first organic material chemically bonds to the Si atoms of the first bonding portion (intermediate X1), and the second organic material chemically bonds to the Si atoms of the second bonding portion (intermediate X2). Then, for convenience, intermediate X1 is selected as one of intermediates X1 and X2, and a third organic material is supplied to intermediate X1, and the reactive functional group of the first organic material reacts with the bondable group of the third organic material to bond them (intermediate Y).

[0255] Thereafter, the intermediate Y thus obtained and the intermediate X2 obtained above are placed facing each other, and the reactive functional groups of the intermediate X2 (second organic material) are reacted with the bondable groups of the intermediate Y (first organic material + third organic material) to bond them together, thereby bonding the first organic material chemically bonded to the Si atoms of the first bonding portion and the second organic material chemically bonded to the Si atoms of the second bonding portion via the third organic material.

[0256] As a result, the first conductive region 15 and the second conductive region 25, as well as the first and second bonding portions, are bonded by reaction products derived from the first to third organic materials. While by-products such as alcohols may be generated, the carbon number thereof may be small as described above, and they can be effectively removed before the first silicon substrate 10 and the second silicon substrate 20 are placed opposite each other, thereby reducing the formation of voids due to the by-products. Furthermore, this method effectively removes any unreacted third organic material that may remain on the intermediate Y on the first silicon substrate 10 before placing the first silicon substrate 10 and the second silicon substrate 20 opposite each other, thereby reducing the amount of unnecessary material (that does not contribute to bonding) remaining between the first silicon substrate 10 and the second silicon substrate 20 in the final stack.

[0257] (16th Example) In the 15th example, the first organic material reacts with the first conductive region 15, the second organic material reacts with the second conductive region 25, and the first organic material and the third organic material capable of reacting with the second organic material are chemically reacted to connect the first conductive region 15 and the second conductive region 25. However, the 16th example differs in that part A is present on at least a portion of the surface of the first and second conductive regions 15, 25, and no chemical reaction occurs between the first and second conductive regions 15, 25 and part A. In other words, the first and second conductive regions 15, 25 are not chemically connected via part A. The other parts have the same configuration as the 15th example, and part A has the same configuration as the second example.

[0258] Portion A exists between the metal atoms of the first conductive region 15 and the metal atoms of the second conductive region 25. Portion A is located on at least a portion of the surface between the first and second conductive regions 15, 25. Portion A is unreacted with the metal atoms of the first conductive region 15 and the metal atoms of the second conductive region 25. Note that the entire surfaces of the first conductive region 15 and the second conductive region 25 may have portion A, or only a portion may have portion A, with the other portions not having portion A. Portion A has the same configuration as described above.

[0259] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to such embodiments and various modifications are possible.

[0260] The present disclosure will be explained in more detail through the following examples, but is not limited to these examples.

[0261] (Comparative Example 1) For one Cu wafer, N ２ The RIE plasma was irradiated at 250 W for 3 minutes.

[0262] (Example 1) Preparation of a sample for measuring conductivity and resistivity ２ The wafer surface was irradiated with RIE plasma to activate it and remove organic contamination. A 5 wt % 1,6-bis(trimethoxysilyl)hexane solution (2-methoxy-1-methylethyl acetate (PGMEA) solution) was passed through a filter to remove particles. The PGMEA solution was then applied to the wafer by spin coating, forming a film. After leaving the wafer to stand for 5 minutes, the wafer surface was cleaned with PGMEA to wash away any organic material that had not adhered to the wafer. The wafer was then heated on a hot stage at 100°C for 5 minutes, causing the wafer and organic material to react, forming an organic film on the wafer (i.e., in Example 1, the reaction product of the organic material was located on one wafer). The conductivity and resistivity of the wafer obtained above were then measured. 1,6-bis(trimethoxysilyl)hexane:

[0263] Example 2 The same procedure as in Example 1 was carried out, except that bis[3-(trimethoxysilyl)propyl]amine was used as the first organic material instead of 1,6-bis(trimethoxysilyl)hexane in Example 1. Bis[3-(trimethoxysilyl)propyl]amine:

[0264] Example 3 The same procedure as in Example 1 was carried out, except that 1,6-hexanediphosphonic acid was used as the first organic material instead of 1,6-bis(trimethoxysilyl)hexane in Example 1. 1,6-Hexylenediphosphonic Acid:

[0265] [Plasma irradiation conditions] Apparatus: AQ-500 manufactured by Mikasa Co., Ltd. Irradiation plasma: N ２ ・Irradiation time: 3 minutes ・Irradiation power: 250W

[0266] [Film Thickness Measurement Conditions] Film thickness was measured using an ellipsometer. Measurement wavelength range: 400-1000 nm Incident angle: 65° The same substrate was measured before film formation (after pretreatment) and after film formation, and the film thickness was determined by calculating the difference.

[0267] [Conductivity measurement] Device name: Nanoscope V+ Dimension ICON manufactured by Bruker AXS (current is also measured simultaneously) Sample bias voltage: 5 V Measurement range: 20 μm × 20 μm Measurement environment: Ar atmosphere Probe (cantilever) product number: DDESP-V2 manufactured by Bruker Effective probe area: 3.14159 × 10 －１４ m ２ The tip diameter of the measurement probe was kept the same. The contact resistance between the measurement probe and the sample was always constant, or even if there was a difference, it was so small that it could be ignored. The measured conductivity value is the average current value obtained.

[0268] [Measurement of Resistivity] When R(all) is the resistance value [Ω] of the entire wafer (wafer + organic film) obtained in Example 1, R(a) is the resistance value [Ω] of the region having the organic film (region having the wafer and the organic film), and R(b) is the resistance value [Ω] of the region not having the organic film (region where only the wafer is present), R(all) is expressed as follows: R(a) = R(a) + R(b) ... (er1).

[0269] The average current value of the Cu wafer (not including an organic film) in Comparative Example 1 was 160 pA. From this value, R(b) [Ω] for Comparative Example 1 was calculated. Specifically, since Voltage V [V] = Current I [pA] × Resistance [Ω] (er2), the sample bias voltage 5 [V] = 160 [pA] × R(b) [Ω], and R(b) [Ω] for Comparative Example 1 = 1 / 32. This value was used as R(b) in Examples 1 and 2.

[0270] Using the value of R(b), the resistance value R(a) in each of Examples 1 and 2 was calculated from the above formula (er1). Furthermore, the resistivity ρ of the organic film was calculated based on the following formula (er3): R(a) = ρ × l ÷ S (er3) [where: ρ = resistivity of the organic film [Ω·m], l = film thickness of the organic film [nm], S = effective probe area [m ２ ]]

[0271] Tables 2 and 3 show the measurement conditions and results.

[0272]

[0273] As the film thickness increases, the film becomes insulating (conductivity becomes 0 pA), but it was found to be conductive in Examples 1 to 3. Also, while general organic films are not conductive, it was found that the film of the present invention is conductive as shown in Examples 1 to 3.

[0274] In Examples 1 to 3, an organic film was formed on a wafer, but by placing another wafer on the organic film, the organic film became the adhesive layer of the present invention, i.e., a laminate of the present invention was formed.

[0275] The method for manufacturing a stacked body according to the present disclosure can be used in a wide range of applications when the first silicon substrate and the second silicon substrate have conductive regions.

[0276] 10, 20 Silicon substrate 15, 25 Conductive region 15a, 25a Activation region 30, 30A, 30B Adhesive layer 31, 32A, 33A, 32B, 33B, 33C Adhesive part 40, 40A, 40B Laminated body 60 Vacant part

Claims

1. A method for manufacturing a laminate including two silicon substrates, comprising: (a) preparing a first silicon substrate having a first conductive region on at least a portion of its surface, and a second silicon substrate; and (b) bonding the surface of the first silicon substrate including the first conductive region to the second silicon substrate with an adhesive layer, wherein the adhesive layer contains a first reaction product derived from a first organic material capable of reacting with a first activated region formed by activating at least a portion of the surface of the first silicon substrate including the first conductive region.

2. The method of claim 1, wherein the first conductive region comprises a metal.

3. The manufacturing method according to claim 2, wherein the metal of the first conductive region is at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru, and Hf.

4. A manufacturing method according to any one of claims 1 to 3, wherein the surface of the first conductive region is exposed.

5. A manufacturing method according to any one of claims 1 to 3, wherein at least a portion of the surface of the first conductive region is in contact with the adhesive layer.

6. The manufacturing method according to any one of claims 1 to 5, wherein the adhesive layer is formed from two or more layers.

7. A manufacturing method according to any one of claims 1 to 6, wherein the first activation region is provided on at least a portion of the first conductive region and at least a portion of the first silicon substrate, the first conductive region includes at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru and Hf, the adhesion layer is in contact with the first activation region, and the thickness of the adhesion layer is 5 nm or less.

8. A method for producing a laminate according to any one of claims 1 to 7, further comprising: the second silicon substrate having a second conductive region on at least a portion of its surface; and the adhesive layer being provided on a second activated region formed by activating at least a portion of the surface of the second silicon substrate facing the second conductive region, and containing a second reaction product derived from a second organic material.

9. The method of claim 8, wherein the second conductive region comprises a metal.

10. The manufacturing method according to claim 8 or 9, wherein the metal of the second conductive region is at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru and Hf.

11. The manufacturing method according to any one of claims 8 to 10, wherein the surface of the second conductive region is exposed.

12. The manufacturing method according to any one of claims 8 to 11, wherein at least a portion of the surface of the second conductive region is in contact with the adhesive layer.

13. The manufacturing method according to any one of claims 8 to 12, wherein the distance between the first conductive region and the second conductive region is 5 nm or less.

14. The manufacturing method according to any one of claims 1 to 13, wherein the thickness of the adhesive layer is 5 nm or less.

15. The manufacturing method according to any one of claims 8 to 14, wherein the first activation region is provided on at least a portion of the first conductive region and at least a portion of the first silicon substrate, the second activation region is provided on at least a portion of the second conductive region and at least a portion of the second silicon substrate, the first conductive region and the second conductive region each contain at least one selected from the group consisting of Cu, Co, Fe, Al, W, Ru, and Hf, the adhesion layer is in contact with the first activation region and the second activation region, and the distance between the first conductive region and the second conductive region is 5 nm or less.

16. A laminate comprising: a first silicon substrate having a first conductive region on at least a portion of its surface; a second silicon substrate located on the side having the first conductive region; and an adhesive layer located between the first silicon substrate and the second silicon substrate, bonding the side of the first silicon substrate having the first conductive region to the second silicon substrate, wherein conductivity is provided between the first silicon substrate and the second silicon substrate.

17. The stack according to claim 16, wherein the second silicon substrate has a second conductive region on at least a portion of its surface, and the adhesive layer bonds the surface having the first conductive region to the surface having the second conductive region.

18. The stack of claim 17, wherein the distance between the first conductive region and the second conductive region is 5 nm or less.

19. The laminate according to any one of claims 16 to 18, wherein the adhesive layer has a thickness of 5 nm or less.

20. The laminate according to any one of claims 16 to 19, wherein the adhesive layer consists of two or more layers.

21. A laminate according to any one of claims 17 to 20, comprising the first conductive region and the second conductive region, the distance between the first conductive region and the second conductive region being 5 nm or less, and the adhesive layer bonding the surface having the first conductive region and the surface having the second conductive region.

22. The electrical conductivity measured in the adhesive layer disposed on the first silicon substrate is 1.0 x 10 －２ ~5.0 x 10 ２ The laminate according to any one of claims 16 to 21, wherein the pA is in the range.

23. Resistivity is 1.5 x 10 －８ ~2.0 x 10 ５ The laminate according to any one of claims 16 to 22, wherein the modulus of elasticity is in the range of Ω·m.

Images