Semiconductor structure and method for manufacturing the same

Abstract

This semiconductor structure is provided with: a semiconductor substrate; a plurality of silicon grains disposed on the semiconductor substrate and hybrid bonded to the semiconductor substrate; and an organic gap filling material filled between the plurality of silicon crystal grains on the semiconductor substrate.

Description

Technical Field

[0001] The present disclosure relates to semiconductor structures and methods of manufacturing the same. Background Art

[0002] In recent years, from the viewpoint of high integration of semiconductor devices, a technique of stacking a semiconductor substrate and a semiconductor chip (eg, silicon crystal grain) in the thickness direction has been studied.

[0003] For example, Patent Document 1 discloses a semiconductor structure including: a group of crystal grains provided on a wiring layer; and a silicon-containing inorganic gap-filling material provided on the wiring layer and surrounding the group of crystal grains.

[0004] Patent Document 1: U.S. Patent Publication No. 2022 / 0013504 Summary of the Invention

[0005] Problems to be solved by the invention

[0006] However, among technologies for stacking semiconductor substrates and silicon crystal grains in the thickness direction, hybrid bonding is being developed as a technology for performing high-density bonding in order to improve data transmission per unit area.

[0007] In the present disclosure, hybrid bonding refers to bonding in which electrodes are bonded to each other and insulating films are bonded to each other by bringing two surfaces where an electrode and an insulating material are exposed into contact with each other.

[0008] In a semiconductor structure having a semiconductor substrate, a plurality of silicon grains, and a gap-filling material bonded by hybrid bonding, when the inorganic gap-filling material described in Patent Document 1 is used as the gap-filling material, warping of the semiconductor structure may occur due to film stress of the inorganic gap-filling material.

[0009] The present disclosure has been made in view of the above-mentioned problems.

[0010] An object of one embodiment of the present disclosure is to provide a semiconductor structure including a semiconductor substrate and a plurality of silicon crystal grains bonded by hybrid bonding, and a gap-filling material, in which warpage is suppressed, and a method for manufacturing the same.

[0011] Solutions to Problems

[0012] Specific solutions for solving the aforementioned problems include the following.

[0013] <1> A semiconductor structure comprises: a semiconductor substrate; a plurality of silicon grains arranged on the semiconductor substrate and hybrid-bonded to the semiconductor substrate; and an organic gap-filling material filled between the plurality of silicon grains on the semiconductor substrate.

[0014] <2> According to the aforementioned <1> In the semiconductor structure, the semiconductor substrate and the plurality of silicon grains each include a bonding layer including an insulating layer and an electrode, and the bonding layer in the semiconductor substrate and the bonding layers in the plurality of silicon grains are hybrid-bonded.

[0015] <3> According to the aforementioned <2> The semiconductor structure, wherein the insulating layer comprises at least one selected from the group consisting of a SiO2 layer, a SiCN layer, a SiN layer, and a resin layer containing a siloxane bond.

[0016] <4> According to the aforementioned <1> ~ <3> The semiconductor structure according to any one of the preceding claims, wherein the organic gap-filling material comprises at least one selected from the group consisting of polyimide, polyamide, polyamideimide, maleimide resin, parylene, polyarylene ether polyimide, polybenzoxazole, benzocyclobutene resin, and epoxy resin.

[0017] <5> According to the aforementioned <1> ~ <4> The semiconductor structure according to any one of the preceding claims, wherein the organic gap-filling material comprises a resin having a siloxane bond.

[0018] <6> According to the aforementioned <1> ~ <5> The semiconductor structure described in any one of the preceding claims further comprises a silicon-containing layer at least interposed between the organic gap-filling material and the semiconductor substrate.

[0019] <7> According to the aforementioned <6> The semiconductor structure, wherein the silicon-containing layer comprises at least one selected from the group consisting of a SiO2 layer, a SiCN layer, a SiN layer, and a resin layer containing a siloxane bond.

[0020] <8> A method for manufacturing a semiconductor structure, which is to manufacture the above <1> ~ <5> The method for a semiconductor structure as described in any one of the preceding claims comprises: a process of temporarily fixing a plurality of silicon grains on a first temporarily fixed substrate; a process of forming an organic gap filling material on the side of the first temporarily fixed substrate on which the plurality of silicon grains are temporarily fixed, thereby filling the organic gap filling material between the plurality of silicon grains; a process of temporarily fixing a second temporarily fixed substrate on the side of the first temporarily fixed substrate on which the organic gap filling material is formed to obtain a stack X1; a process of removing the first temporarily fixed substrate from the stack X1 to obtain a stack X2 on which the plurality of silicon grains are exposed; a process of performing at least one of cleaning and polishing on the exposed surfaces of the plurality of silicon grains in the stack X2; a process of mixing and bonding a semiconductor substrate with the exposed surfaces of the plurality of silicon grains on which at least one of cleaning and polishing has been performed to obtain a stack X3; and a process of obtaining the semiconductor structure by removing the second temporarily fixed substrate from the stack X3.

[0021] <9> According to the aforementioned <8> The method for manufacturing a semiconductor structure further includes: after the process of temporarily fixing the plurality of silicon grains on the first temporary fixing substrate and before the process of filling the organic gap filling material between the plurality of silicon grains, forming a silicon-containing layer on the side of the first temporary fixing substrate to which the plurality of silicon grains are temporarily fixed, thereby covering at least the exposed surface of the first temporary fixing substrate with the silicon-containing layer.

[0022] Effects of the Invention

[0023] According to one embodiment of the present disclosure, a semiconductor structure including a semiconductor substrate and a plurality of silicon crystal grains bonded by hybrid bonding, and a gap-filling material, in which warpage is suppressed, and a method for manufacturing the same are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] [ Figure 1 ] is a schematic cross-sectional view showing an example of the semiconductor structure disclosed herein.

[0025] [ Figure 2A ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention.

[0026] [ Figure 2B ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention.

[0027] [ Figure 2C ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention.

[0028] [ Figure 2D ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention.

[0029] [ Figure 2E ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention.

[0030] [ Figure 2F ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention.

[0031] [ Figure 2G ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention.

[0032] [ Figure 2H ] is a schematic process diagram showing an example of a method for manufacturing the semiconductor structure disclosed in the present invention. DETAILED DESCRIPTION

[0033] In the present disclosure, a numerical range expressed using “to” means a range including the numerical values ​​described before and after “to” as the lower limit and the upper limit.

[0034] In the numerical ranges recorded in stages in this disclosure, the upper limit or lower limit recorded in one numerical range may also be replaced by the upper limit or lower limit of the numerical range recorded in other stages. In addition, in the numerical ranges recorded in this disclosure, the upper limit or lower limit of the numerical range may also be replaced by the value shown in the Examples.

[0035] [Semiconductor structure]

[0036] The semiconductor structure disclosed herein comprises:

[0037] semiconductor substrates;

[0038] a plurality of silicon grains disposed on a semiconductor substrate and hybrid-bonded to the semiconductor substrate; and

[0039] An organic gap-filling material is filled between a plurality of silicon grains on a semiconductor substrate.

[0040] Compared to the semiconductor structure disclosed herein, the technology described in Patent Document 1 (US Patent Publication No. 2022 / 0013504) uses an inorganic gap-filling material as the gap-filling material, and thus has a problem of warping of the semiconductor structure due to film stress of the gap-filling material.

[0041] In contrast, the semiconductor structure of the present disclosure can suppress the problem of warping of the semiconductor structure due to the film stress of the inorganic gap-filling material by using an organic gap-filling material as the gap-filling material.

[0042] The semiconductor structure disclosed herein uses an organic gap-filling material as the gap-filling material. Compared with the case where an inorganic gap-filling material is formed by a vapor growth method (i.e., a dry process) such as CVD (Chemical Vapor Deposition), it also has the advantage of being able to form the gap-filling material in a short time and simply by a wet process such as coating or printing.

[0043] <An Example of a Semiconductor Structure>

[0044] Hereinafter, an example of the semiconductor structure (semiconductor structure 100 ) of the present disclosure will be described with reference to the drawings.

[0045] However, the semiconductor structure of the present disclosure is not limited to the following example.

[0046] In the following description, substantially the same elements (for example, members or parts) are denoted by the same reference numerals, and overlapping descriptions may be omitted.

[0047] like Figure 1 As shown, a semiconductor structure 100 as an example of a semiconductor structure disclosed herein comprises: a semiconductor substrate 10; a plurality of silicon grains 20 arranged on the semiconductor substrate 10 and hybrid-bonded with the semiconductor substrate 10; and an organic gap-filling material 30 filled between the plurality of silicon grains on the semiconductor substrate.

[0048] The semiconductor structure 100 further includes a silicon-containing layer 32 at least interposed between the organic gap-filling material 30 and the semiconductor substrate 10 . The silicon-containing layer 32 is interposed between the organic gap-filling material 30 and the semiconductor substrate 10 , and between the organic gap-filling material 30 and the silicon grains 20 .

[0049] From the viewpoint of suppressing warping of the semiconductor structure, the silicon-containing layer 32 is not essential and may be omitted.

[0050] The semiconductor substrate 10 includes a substrate body 12 , a bonding layer 14 provided on one surface of the substrate body 12 , and a through-electrode 16 electrically connected to the bonding layer 14 and penetrating the substrate body 12 .

[0051] The substrate body 12 in the semiconductor substrate 10 is not particularly limited as long as it is a commonly used substrate body, and a silicon substrate can be given as an example. A specific example of the substrate body 12 will be described later.

[0052] An integrated circuit (not shown) is formed inside the substrate body 12 of the semiconductor substrate 10 .

[0053] The bonding layer 14 in the semiconductor substrate 10 includes an insulating layer and an electrode (not shown) penetrating the insulating layer.

[0054] The integrated circuit in the substrate body 12 is connected to the electrodes in the bonding layer 14. These structures are conventional and therefore are not shown in the figure.

[0055] The silicon crystal grain 20 includes a crystal grain body 22 and a bonding layer 24 provided on one surface side of the crystal grain body 22 .

[0056] An integrated circuit (not shown) is formed inside the silicon crystal grain 20 .

[0057] The bonding layer 24 in the silicon crystal grain 20 includes an insulating layer and an electrode (not shown) penetrating the insulating layer. These structures are conventional and therefore are not shown in the figure.

[0058] In the semiconductor structure 100 , a semiconductor substrate 10 is hybrid-bonded to a plurality of silicon crystal grains 20 . More specifically, a bonding layer 14 in the semiconductor substrate 10 is hybrid-bonded to a bonding layer 24 in the silicon crystal grains 20 .

[0059] As this hybrid bonding, a well-known hybrid bonding can be applied.

[0060] The semiconductor structure 100 includes an organic gap-filling material 30 filled between a plurality of silicon grains 20 on a semiconductor substrate 10 .

[0061] Therefore, compared to the case where the gap filler is an inorganic gap filler (for example, the aforementioned Patent Document 1 (U.S. Patent Publication No. 2022 / 0013504)), the film stress of the gap filler can be reduced, thereby reducing the warping of the entire semiconductor structure. As a result of reducing the warping of the entire semiconductor structure, for example, it is possible to reduce bonding defects and / or positional shifts between bonded substrates caused by warping.

[0062] The semiconductor structure 100 further includes a silicon-containing layer 32 at least interposed between the organic gap-filling material 30 and the semiconductor substrate 10 .

[0063] From the viewpoint of suppressing warpage of the semiconductor structure, the silicon-containing layer 32 is not essential.

[0064] When the semiconductor structure 100 includes the silicon-containing layer 32 , the adhesion between the organic gap-filling material 30 and the semiconductor substrate 10 is improved.

[0065] In this example, the silicon-containing layer 32 is interposed between the organic gap-filling material 30 and the semiconductor substrate 10, and between the organic gap-filling material 30 and the side surfaces of the plurality of silicon crystal grains 20. As a result, in the semiconductor structure 100, the adhesion between the organic gap-filling material 30 and the semiconductor substrate 10, and the adhesion between the organic gap-filling material 30 and the plurality of silicon crystal grains 20, is improved.

[0066] More specifically, in the semiconductor structure 100, a recess is formed by the side surfaces of the plurality of silicon crystal grains 20 and the surface of the semiconductor substrate 10. The walls of the recess (i.e., the side surfaces of the plurality of silicon crystal grains 20 and the surface of the semiconductor substrate 10) are covered with a silicon-containing layer 32. The recess, whose walls are covered by the silicon-containing layer 32, is filled with an organic gap-filling material 30.

[0067] The silicon-containing layer will be described in detail later.

[0068] <One Embodiment of the Method for Manufacturing a Semiconductor Structure (Manufacturing Method X)>

[0069] The method of manufacturing the semiconductor structure of the present disclosure is not particularly limited.

[0070] As one embodiment of a method for producing the semiconductor structure of the present disclosure, the following “Production Method X” can be cited.

[0071] Preparation method X includes:

[0072] a step of temporarily fixing a plurality of silicon crystal grains on a first temporary fixing substrate;

[0073] forming an organic gap-filling material on one side of the first temporary fixing substrate where the plurality of silicon crystal grains are temporarily fixed, thereby filling the organic gap-filling material between the plurality of silicon crystal grains;

[0074] A step of temporarily fixing a second temporary fixing substrate to the side of the first temporary fixing substrate on which the organic gap-filling material is formed to obtain a laminate X1;

[0075] a step of removing the first temporary fixing substrate from the stacked body X1 to obtain a stacked body X2 with exposed silicon grains;

[0076] A step of performing at least one of cleaning and polishing on the exposed surfaces of the plurality of silicon crystal grains in the stack X2;

[0077] a step of hybrid bonding a semiconductor substrate and exposed surfaces of a plurality of silicon crystal grains subjected to at least one of cleaning and polishing to obtain a laminate X3; and

[0078] A step of obtaining a semiconductor structure by removing the second temporary fixing substrate from the stacked body X3.

[0079] Method X may further include: after the step of temporarily fixing the plurality of silicon grains on the first temporary fixing substrate and before the step of filling the organic gap-filling material between the plurality of silicon grains, forming a silicon-containing layer on the side of the first temporary fixing substrate to which the plurality of silicon grains are temporarily fixed, thereby covering at least the exposed surface of the first temporary fixing substrate with the silicon-containing layer.

[0080] In this manner, a semiconductor structure (eg, semiconductor structure 100 ) including a silicon-containing layer (eg, silicon-containing layer 32 ) interposed at least between the organic gap-filling material and the semiconductor substrate can be manufactured.

[0081] The silicon-containing layer can be formed to cover at least the exposed surface of the first temporary fixing substrate and the side surfaces of the silicon grains. Thus, a semiconductor structure having a silicon-containing layer between the organic gap-filling material and the semiconductor substrate, and between the organic gap-filling material and the silicon grains can be manufactured (see preparation method X1 described later).

[0082] <An Example of Production Method X (Production Method X1)>

[0083] Figures 2A to 2HThis is a schematic process diagram showing an example of Production Method X (hereinafter also referred to as "Production Method X1").

[0084] Preparation method X1 includes Figures 2A to 2H Steps A to H are shown.

[0085] The manufacturing method X1 is an example in which the step of forming the silicon-containing layer is included. The step of forming the silicon-containing layer may be omitted.

[0086] (Process A)

[0087] Preparation method x1 includes Figure 2A Process A shown.

[0088] like Figure 2A As shown, step A is a step of temporarily fixing the plurality of silicon crystal grains 20 on the first temporary fixing substrate 40 .

[0089] As the first temporary fixing substrate 40 , for example, a silicon substrate, a glass substrate, a resin substrate, or the like can be used.

[0090] Temporary fixation can be performed, for example, by the following methods:

[0091] Methods using adhesives such as acrylic and epoxy polymers;

[0092] Methods using heat-resistant resins such as polyimide, polyamide-imide, polymaleimide, and silicone polymers;

[0093] Direct bonding of SiO2, etc.

[0094] The first temporary fixing substrate 40 is removed (ie, peeled off) during the process X1. Therefore, the surface of the first fixing substrate 40 facing the silicon crystal grains 20 may be subjected to a surface treatment to facilitate peeling from the silicon crystal grains 20.

[0095] (Process B)

[0096] Preparation method x1 includes Figure 2B Process B shown.

[0097] like Figure 2B As shown, step B is a step of forming a silicon-containing layer 32A on the side of the first temporary fixing substrate 40 where the plurality of silicon crystal grains 20 are temporarily fixed, thereby covering at least the exposed surface of the first temporary fixing substrate 40 with the silicon-containing layer 32A.

[0098] In this example, the silicon-containing layer 32A is formed to cover the exposed surface of the first temporary fixing substrate 40 and the upper surfaces and side surfaces of the plurality of silicon crystal grains 20. The silicon-containing layer 32A on the upper surfaces of the plurality of silicon crystal grains 20 is finally removed by polishing.

[0099] When the silicon-containing layer 32A is a SiO 2 film, the silicon-containing layer 32A can be formed by a vapor phase growth method such as sputtering, CVD (Chemical Vapor Deposition), or ALD (Atomic Layer Deposition).

[0100] When the silicon-containing layer 32A is a resin film containing a SiO structure, the silicon-containing layer 32A can be formed by a wet process such as a coating method (e.g., a method including coating and heating) or a printing method. A specific example of the method for forming the silicon-containing layer 32A is the same as the specific example of the method for forming the organic gap-filling material described later.

[0101] Step B may also be omitted.

[0102] (Process C)

[0103] Preparation method x1 includes Figure 2C Process C shown.

[0104] like Figure 2C As shown, step C is a step of forming an organic gap-filling material 30A on the side of the first temporary fixing substrate 40 where the plurality of silicon crystal grains 20 are temporarily fixed, thereby filling the organic gap-filling material 30A between the plurality of silicon crystal grains 20 .

[0105] The organic gap-filling material 30A can be formed by a wet process such as spray coating, spin coating, screen printing, doctor blade coating, or inkjet printing.

[0106] (Process D)

[0107] Preparation method x1 includes Figure 2D Process D shown.

[0108] like Figure 2D As shown, step D is a step of polishing the side of the first temporary fixing substrate 40 on which the organic gap-filling material 30A is formed until the upper surfaces of the plurality of silicon crystal grains 20 are exposed.

[0109] This polishing removes the organic gap-filling material 30A and the silicon-containing layer 32A on the upper surfaces of the plurality of silicon crystal grains 20 . As a result, the remaining organic gap-filling material and the silicon-containing layer become the organic gap-filling material 30 and the silicon-containing layer 32 .

[0110] Polishing can be performed by conventional methods such as mechanical polishing, chemical polishing, and chemical mechanical polishing.

[0111] Furthermore, in the aforementioned steps B and D, the organic gap filler 30A and the silicon-containing layer 32A do not need to be formed on the upper surfaces of the plurality of silicon crystal grains 20. Specifically, the organic gap filler 30 and the silicon-containing layer 32 may be selectively formed on the exposed surface of the first temporary fixing substrate 40 and the side surfaces of the silicon crystal grains 20, respectively. In this case, step D can be omitted.

[0112] (Process E)

[0113] Preparation method x1 includes Figure 2E Step E shown.

[0114] like Figure 2E As shown, step E is a step of temporarily fixing the second temporary fixing substrate 42 to the side of the first temporary fixing substrate 40 where the organic gap filler 30 is formed, to obtain a laminate X101. The laminate X101 is an example of the laminate X1 in the manufacturing method X.

[0115] Temporary fixation can be performed using, for example, an adhesive.

[0116] The second temporary fixing substrate 42 is removed (ie, peeled off) during the process X1. Therefore, the surface of the second fixing substrate 42 facing the silicon crystal grains 20 may be subjected to a surface treatment for facilitating peeling from the silicon crystal grains 20.

[0117] (Process F)

[0118] Preparation method x1 includes Figure 2F Process F shown.

[0119] like Figure 2F As shown, step F is a step of removing the first temporary fixing substrate 40 from the stacked body X101 to obtain a stacked body X102 in which a plurality of silicon crystal grains 20 are exposed.

[0120] The laminate X102 is an example of the laminate X2 in the manufacturing method X.

[0121] The first temporary fixing substrate 40 can be removed by, for example, the following method.

[0122] When the first temporary fixing substrate 40 is temporarily fixed by an acrylic adhesive or an epoxy adhesive, the first temporary fixing substrate 40 can be removed by, for example, thermal foaming, mechanical peeling, thermal sliding, laser peeling, or the like.

[0123] When the first temporary fixing substrate 40 is temporarily fixed using a heat-resistant resin such as polyimide, polyamideimide, polymaleimide, or siloxane polymer, the first temporary fixing substrate 40 can be removed by, for example, laser peeling, mechanical peeling, or thermal sliding.

[0124] When the first temporary fixing substrate 40 is temporarily fixed by direct bonding of SiO 2 particles, the first temporary fixing substrate 40 can be removed by laser lift-off using infrared rays or the like, for example.

[0125] (Process F2)

[0126] Production method X1 includes step F2 (not shown).

[0127] Step F2 is a step of performing at least one of cleaning and polishing on the exposed surfaces of the plurality of silicon crystal grains 20 in the stacked body X102 (that is, the exposed surface of the bonding layer 24 ).

[0128] Cleaning and / or polishing may be performed on the entire stacked body X102 including the exposed surfaces of the plurality of silicon crystal grains 20 (ie, the exposed surface of the bonding layer 24 ).

[0129] The cleaning method is not particularly limited, and examples thereof include plasma cleaning, two-fluid cleaning, ultrasonic cleaning, and cleaning with a cleaning liquid.

[0130] The polishing method is not particularly limited, and examples thereof include CMP (Chemical Mechanical Polishing).

[0131] (Process G)

[0132] Preparation method x1 includes Figure 2G Step G shown.

[0133] like Figure 2G As shown, step G is a step of hybrid bonding the semiconductor substrate 10 and the exposed surfaces of the plurality of silicon crystal grains 20 subjected to at least one of cleaning and polishing (ie, the exposed surfaces of the bonding layer 24 ) to obtain a laminate X103 .

[0134] The laminate X103 is an example of the laminate X3 in the manufacturing method X.

[0135] The semiconductor substrate 10 is Figure 1 The semiconductor substrate described in the example shown includes a substrate body 12 , a bonding layer 14 provided on one surface side of the substrate body 12 , and a through electrode 16 electrically connected to the bonding layer 14 and penetrating the substrate body 12 .

[0136] In step G, the bonding layer 24 in the plurality of silicon crystal grains 20 and the bonding layer 14 in the semiconductor substrate 10 are hybrid-bonded.

[0137] (Process G2)

[0138] Preparation method x1 includes Figure 2HStep H shown.

[0139] like Figure 2H As shown, process H is performed by Figure 2G A step of removing the second temporary fixing substrate 42 from the laminate X103 to obtain the semiconductor structure 100.

[0140] Through process H, we can obtain Figure 2H and Figure 1 The semiconductor structure 100 is shown.

[0141] The second temporary fixing substrate 42 can be removed by the same method as the removal of the first temporary fixing substrate 40 .

[0142] Hereinafter, preferred embodiments of the semiconductor structure disclosed herein will be described.

[0143] <Semiconductor Substrate>

[0144] The semiconductor structure of the present disclosure (eg, semiconductor structure 100 ) includes a semiconductor substrate (eg, semiconductor substrate 10 ).

[0145] The semiconductor substrate may include a substrate body (eg, substrate body 12) and a bonding layer (eg, bonding layer 14) disposed on one side of the substrate body. The bonding layer may also be disposed on both sides of the substrate body.

[0146] (Board main body)

[0147] The material of the substrate body is not particularly limited as long as it is a material commonly used as a semiconductor substrate.

[0148] The substrate body preferably contains at least one element selected from Si, Al, Ti, Zr, Hf, Fe, Ni, Cu, Ag, Au, Ga, Ge, Sn, Pd, As, Pt, Mg, In, Ta and Nb.

[0149] More specifically, as the material of the substrate body, for example, there are:

[0150] Semiconductors (e.g. Si, InP, GaN, GaAs, InGaAs, InGaAlAs, SiC, etc.);

[0151] Oxides, carbides, or nitrides (e.g., borosilicate glass (Pyrex (registered trademark)), quartz glass (SiO2), sapphire, ZrO2, Si3N4, AlN, etc.);

[0152] Piezoelectrics or dielectrics (e.g. BaTiO3, LiNbO3, SrTiO3, diamond, etc.);

[0153] Metals (e.g. Al, Ti, Fe, Cu, Ag, Au, Pt, Pd, Ta, Nb, etc.);

[0154] Resins (such as polydimethylsiloxane (PDMS), epoxy resin, phenolic resin, polyimide, benzocyclobutene resin, polybenzoxazole, etc.); etc.

[0155] The substrate body may include only one of these materials, or may include two or more of them.

[0156] The substrate body is preferably a silicon substrate, a GaAs substrate, a SiC substrate, a diamond substrate, a glass substrate, or a resin substrate, and is typically a silicon substrate.

[0157] The substrate body may have a multi-layer structure.

[0158] (Joint layer)

[0159] The bonding layer may include an insulating layer and an electrode (eg, a Cu electrode) penetrating the insulating layer.

[0160] The insulating layer in the bonding layer can be formed by a vapor phase growth method such as sputtering or CVD.

[0161] The electrodes in the bonding layer can be formed by a known manufacturing method such as a damascene process or a semi-additive process.

[0162] The insulating layer in the bonding layer preferably includes at least one selected from the group consisting of a SiO 2 layer, a SiCN layer, a SiN layer, and a resin layer containing a siloxane bond.

[0163] The SiO 2 layer, the SiCN layer, and the SiN layer serving as the insulating layer can be formed by vapor phase growth methods such as sputtering, CVD (Chemical Vapor Deposition), and ALD (Atomic Layer Deposition).

[0164] Examples of the material of the siloxane bond-containing resin layer of the insulating layer include the same materials as those of the “siloxane bond-containing resin layer” as the “silicon-containing layer” described later.

[0165] Regarding the method for forming the resin layer containing a siloxane bond as the insulating layer, the example of the method for forming the "resin layer containing a siloxane bond" as the "silicon-containing layer" described later may be appropriately referred to.

[0166] (Through electrode)

[0167] The semiconductor substrate may include a through-electrode penetrating the substrate body.

[0168] The through-electrode is not particularly limited, and a known through-electrode can be applied.

[0169] <Silicon Grains>

[0170] The semiconductor structure (eg, semiconductor structure 100 ) of the present disclosure includes a plurality of hybrid-bonded silicon grains (eg, silicon grain 20 ) on a semiconductor substrate (eg, semiconductor substrate 10 ).

[0171] As the silicon crystal grains, ordinary silicon crystal grains obtained by forming integrated circuits on a silicon substrate (eg, silicon crystal grains) and then cutting into chip shapes can be used.

[0172] The silicon die may include a bonding layer.

[0173] Preferred aspects of the bonding layer in the silicon crystal grains are the same as those of the bonding layer in the semiconductor substrate.

[0174] A preferred embodiment of the semiconductor structure disclosed herein is an embodiment in which the semiconductor substrate and the plurality of silicon crystal grains each include a bonding layer including an insulating layer and an electrode, and the bonding layer in the semiconductor substrate and the bonding layers in the plurality of silicon crystal grains are hybrid-bonded.

[0175] The interval between the plurality of silicon grains (ie, the distance between the side surface of a silicon grain and the side surface of an adjacent silicon grain) is preferably 0.1 μm to 100,000 μm, more preferably 1 μm to 10,000 μm, and further preferably 50 μm to 1,000 μm.

[0176] The thickness of the silicon crystal grains is preferably 5 μm to 700 μm, more preferably 10 μm to 300 μm, and even more preferably 15 μm to 100 μm.

[0177] Hybrid bonding can be performed by bonding the insulating layer and the electrode in the bonding layer of the silicon crystal grain to the insulating layer and the electrode in the bonding layer of the semiconductor substrate.

[0178] As the hybrid bonding, for example, a known hybrid bonding described in Patent Document 1 (US Patent Publication No. 2022 / 0013504) can be applied.

[0179] <Organic Gap Filling Materials>

[0180] The semiconductor structure (eg, semiconductor structure 100 ) disclosed herein includes an organic gap-filling material (eg, organic gap-filling material 30 ) filled between a plurality of silicon grains (eg, silicon grains 20 ) on a semiconductor substrate (eg, semiconductor substrate 10 ).

[0181] The organic gap-filling material includes at least one organic material (preferably a resin, more preferably a heat-resistant resin).

[0182] The glass transition temperature of the organic material in the organic gap-filling material is preferably 110°C to 300°C, more preferably 120°C to 300°C, and even more preferably 150°C to 300°C.

[0183] The glass transition temperature can be measured by the following method.

[0184] That is, a test piece of organic material with a width of 4 mm and a length of 20 mm was prepared. A thermal analyzer (TMA-50) manufactured by Shimadzu Corporation was used to analyze the sample in the temperature range of 25°C to 350°C at a heating rate of 5°C / min and a load of 14 g / mm. 2 The glass transition temperature (Tg) of the test piece can be determined by TMA measurement under the measurement conditions of the temperature-test piece elongation curve obtained.

[0185] Examples of the resin in the organic gap-filling material include polyimide, polyamide, polyamideimide, maleimide resin, polyparaxylene, polyalkylene ether, polybenzoxazole, benzocyclobutene resin, and epoxy resin.

[0186] In addition, examples of the resin in the organic gap-filling material include resins containing a siloxane bond.

[0187] Examples of the resin containing a siloxane bond include the same resins as those contained in the “resin layer containing a siloxane bond as a silicon-containing layer” described later.

[0188] The organic gap-filling material including a resin can be formed by a wet process such as a coating method (eg, a method including coating and heating) or a printing method.

[0189] In this case, for example, a coating liquid for forming an organic gap-filling material containing a resin precursor is applied to the side of the semiconductor substrate on which the silicon-containing layer is formed, and then heated to obtain the organic gap-filling material.

[0190] The purpose of heating here is to dry the solvent in the coating liquid and to cure the resin precursor in the coating liquid to obtain the resin. The heating for drying and the heating for curing the resin precursor may be carried out separately.

[0191] Coating can be performed by a known coating method such as spin coating, slit coating, spray coating, screen printing, doctor blade coating, or inkjet printing.

[0192] <An Example of a Coating Liquid for Forming an Organic Gap-Filling Material>

[0193] An example of the coating liquid for forming an organic gap-filling material is a solution containing a resin material.

[0194] The solution comprising the resin material preferably comprises:

[0195] Compound (A) having a cationic functional group containing at least one of a primary nitrogen atom and a secondary nitrogen atom, and having a weight average molecular weight of 90 to 400,000;

[0196] a cross-linking agent (B) having three or more -C(═O)OX groups (X is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms) in the molecule, one or more and six or less of the three or more -C(═O)OX groups being -C(═O)OH groups, and having a weight-average molecular weight of 200 to 600; and

[0197] Polar solvent (D).

[0198] (Compound (A))

[0199] Compound (A) is a compound having a cationic functional group containing at least one of a primary nitrogen atom and a secondary nitrogen atom and having a weight average molecular weight of 90 to 400,000. The cationic functional group is not particularly limited as long as it is a functional group capable of carrying a positive charge and containing at least one of a primary nitrogen atom and a secondary nitrogen atom.

[0200] Furthermore, the compound (A) may contain a tertiary nitrogen atom in addition to the primary and secondary nitrogen atoms.

[0201] In the present disclosure, "primary nitrogen atom" refers to a nitrogen atom bonded only to two hydrogen atoms and one atom other than a hydrogen atom (for example, a nitrogen atom contained in a primary amino group (-NH2 group)), or a nitrogen atom bonded only to three hydrogen atoms and one atom other than a hydrogen atom (cation).

[0202] In addition, a "secondary nitrogen atom" refers to a nitrogen atom bonded only to one hydrogen atom and two atoms other than hydrogen atoms (i.e., a nitrogen atom contained in a functional group represented by the following formula (a)), or a nitrogen atom bonded only to two hydrogen atoms and two atoms other than hydrogen atoms (cation).

[0203] Furthermore, a "tertiary nitrogen atom" refers to a nitrogen atom bonded only to three atoms other than hydrogen atoms (i.e., a nitrogen atom serving as a functional group represented by the following formula (b)), or a nitrogen atom bonded only to one hydrogen atom and three atoms other than hydrogen atoms (cation).

[0204] [Chemistry 1]

[0205]

[0206] In formula (a) and formula (b), * represents a bonding position to an atom other than a hydrogen atom.

[0207] The functional group represented by formula (a) may be a secondary amino group (-NHR a Base; among them, R a The functional group representing a part of the group (representing an alkyl group) may be a divalent linking group contained in the polymer skeleton.

[0208] In addition, the functional group represented by formula (b) (ie, the tertiary nitrogen atom) may be a tertiary amino group (-NR b R c Base; among them, R b and R c The functional groups each independently represent a part of an alkyl group may be trivalent linking groups contained in the polymer skeleton.

[0209] The weight average molecular weight of compound (A) is 90 or more and 400,000 or less. Examples of compound (A) include aliphatic amines, compounds having a siloxane bond (Si-O bond) and an amino group, and amine compounds having a ring structure but not having a Si-O bond in the molecule. When compound (A) is an aliphatic amine, the weight average molecular weight is preferably 10,000 or more and 200,000 or less. When compound (A) is a compound having a siloxane bond (Si-O bond) and an amino group, the weight average molecular weight is preferably 130 or more and 10,000 or less, more preferably 130 or more and 5,000 or less, and further preferably 130 or more and 2,000 or less. When compound (A) is an amine compound having a ring structure but not having a Si-O bond in the molecule, the weight average molecular weight is preferably 90 or more and 600 or less.

[0210] In addition, in this disclosure, the weight average molecular weight is the weight average molecular weight measured by GPC (Gel Permeation Chromatography) method for substances other than monomers and converted into polyethylene glycol.

[0211] Specifically, regarding the weight-average molecular weight, an aqueous solution having a sodium nitrate concentration of 0.1 mol / L was used as the developing solvent, and an analytical apparatus Shodex DET RI-101 and two analytical columns (TSKgel G6000PWXL-CP and TSKgel G3000PWXL-CP manufactured by Tosoh Corporation) were used to detect the refractive index at a flow rate of 1.0 mL / min. Polyethylene glycol / polyethylene oxide was used as the standard and the weight-average molecular weight was calculated using analytical software (Empower 3 manufactured by Waters).

[0212] Furthermore, the compound (A) may further have an anionic functional group, a nonionic functional group, or the like, as necessary.

[0213] The nonionic functional group may be a hydrogen bond accepting group or a hydrogen bond donating group. Examples of the nonionic functional group include a hydroxyl group, a carbonyl group, and an ether group (-O-).

[0214] The anionic functional group is not particularly limited as long as it is a functional group capable of carrying a negative charge. Examples of the anionic functional group include a carboxylic acid group, a sulfonic acid group, and a sulfate group.

[0215] Examples of the compound (A) include aliphatic amines, and more specifically, polymers of alkyleneimines such as ethyleneimine, propyleneimine, butyleneimine, pentyleneimine, hexyleneimine, heptyleneimine, octyleneimine, trimethyleneimine, tetramethyleneimine, pentamethyleneimine, hexamethyleneimine, and octamethyleneimine, i.e., polyalkyleneimines; polyallylamine; and polyacrylamide.

[0216] Polyethyleneimine (PEI) can be produced by the known methods described in Japanese Patent Publication No. 43-8828, Japanese Patent Publication No. 49-33120, Japanese Patent Application Laid-Open No. 2001-213958, International Publication No. 2010 / 137711, etc. Polyalkyleneimines other than polyethyleneimine can also be produced by the same method as polyethyleneimine.

[0217] Compound (A) is also preferably a derivative of the above-mentioned polyalkyleneimine (a polyalkyleneimine derivative; particularly preferably a polyethyleneimine derivative). The polyalkyleneimine derivative is not particularly limited as long as it can be produced using the above-mentioned polyalkyleneimine. Specifically, examples include polyalkyleneimine derivatives in which an alkyl group (preferably an alkyl group having 1 to 10 carbon atoms) or an aryl group is introduced into the polyalkyleneimine, and polyalkyleneimine derivatives in which a crosslinking group such as a hydroxyl group is introduced into the polyalkyleneimine.

[0218] These polyalkyleneimine derivatives can be produced by a commonly used method using the above-mentioned polyalkyleneimine, and specifically, can be produced according to the method described in, for example, Japanese Patent Application Laid-Open No. 6-016809.

[0219] Furthermore, as the polyalkyleneimine derivative, highly branched polyalkyleneimine obtained by reacting a cationic functional group-containing monomer with polyalkyleneimine to increase the branching degree of the polyalkyleneimine is also preferred.

[0220] Examples of methods for obtaining highly branched polyalkyleneimines include: a method in which a cationic functional group-containing monomer is reacted with a polyalkyleneimines having a plurality of secondary nitrogen atoms in its backbone to replace at least one of the plurality of secondary nitrogen atoms with the cationic functional group-containing monomer; a method in which a cationic functional group-containing monomer is reacted with a polyalkyleneimines having a plurality of primary nitrogen atoms at its terminals to replace at least one of the plurality of primary nitrogen atoms with the cationic functional group-containing monomer; and the like.

[0221] Examples of the cationic functional group introduced to increase the branching degree include aminoethyl, aminopropyl, diaminopropyl, aminobutyl, diaminobutyl, and triaminobutyl. From the perspective of reducing the cationic functional group equivalent and increasing the cationic functional group density, the aminoethyl group is preferred.

[0222] The polyethyleneimine and its derivatives may be commercially available products. For example, polyethyleneimine and its derivatives commercially available from Nippon Shokubai Co., Ltd., BASF Corporation, MP-Biomedicals Corporation, etc. may be appropriately selected and used.

[0223] Examples of the compound (A) include compounds having a Si—O bond and an amino group in addition to the aforementioned aliphatic amines.

[0224] The compound having a Si—O bond and an amino group will be described later in the description of the silicon-containing layer.

[0225] Examples of the compound (A) include amine compounds having a ring structure.

[0226] Among them, amine compounds having a weight average molecular weight of 90 to 600 or less having a ring structure are preferred. Examples of amine compounds having a weight average molecular weight of 90 to 600 or less having a ring structure include alicyclic amines, aromatic amines, and heterocyclic amines. The molecule may have multiple ring structures, which may be the same or different. As amine compounds having a ring structure, compounds having an aromatic ring are more preferred in order to easily obtain a compound that is more stable to heat.

[0227] In addition, as the amine compound having a ring structure and a weight-average molecular weight of 90 to 600, compounds having primary amino groups are preferred from the perspective of easily forming a thermally crosslinked structure such as an amide, amideimide, or imide with the crosslinking agent (B), thereby improving heat resistance. Furthermore, as the amine compound, diamine compounds having two primary amino groups and triamine compounds having three primary amino groups are preferred from the perspective of easily increasing the number of thermally crosslinked structures such as an amide, amideimide, or imide with the crosslinking agent (B), thereby further improving heat resistance.

[0228] Examples of the alicyclic amine include cyclohexylamine and dimethylaminocyclohexane.

[0229] Examples of the aromatic cyclic amine include diaminodiphenyl ether, xylylenediamine (preferably p-phenylenediamine), diaminobenzene, diaminotoluene, methylenedianiline, dimethyldiaminobiphenyl, bis(trifluoromethyl)diaminobiphenyl, diaminobenzophenone, diaminobenzanilide, bis(aminophenyl)fluorene, bis(aminophenoxy)benzene, bis(aminophenoxy)biphenyl, dicarboxydiaminodiphenylmethane, diaminoresorcinol, dihydroxybenzidine, diaminobenzidine, 1,3,5-triaminophenoxybenzene, 2,2'-dimethylbenzidine, tris(4-aminophenyl)amine, 2,7-diaminofluorene, 1,9-diaminofluorene, and dibenzylamine.

[0230] Examples of the heterocyclic ring of the heterocyclic amine include a heterocyclic ring containing a sulfur atom as a heteroatom (e.g., a thiophene ring), or a heterocyclic ring containing a nitrogen atom as a heteroatom (e.g., a 5-membered ring such as a pyrrole ring, a pyrrolidine ring, a pyrazole ring, an imidazole ring, and a triazole ring; a 6-membered ring such as an isocyanurate ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a piperidine ring, a piperazine ring, and a triazine ring; and a condensed ring such as an indole ring, an indoline ring, a quinoline ring, an acridine ring, a naphthyridine ring, a quinazoline ring, a purine ring, and a quinoxaline ring).

[0231] For example, examples of the heterocyclic amine having a nitrogen-containing heterocyclic ring include melamine, melamine diamide, melam, melem, and tris(4-aminophenyl)amine.

[0232] Furthermore, examples of the amine compound having both a heterocyclic ring and an aromatic ring include N2,N4,N6-tris(4-aminophenyl)-1,3,5-triazine-2,4,6-triamine.

[0233] Compound (A) has a primary or secondary amino group, and therefore can firmly bond the substrates to each other through electrostatic interaction with functional groups such as hydroxyl, epoxy, carboxyl, amino, and mercapto groups that may be present on the surfaces of the first and second substrates, or by tightly forming covalent bonds with the aforementioned functional groups.

[0234] Furthermore, compound (A) has primary or secondary amino groups and is therefore readily soluble in the polar solvent (D) described below. Using a compound (A) that readily dissolves in a polar solvent (D) increases affinity for the hydrophilic surface of substrates such as silicon substrates, making it easier to form a smooth film and reducing the thickness of the joint where multiple substrate stacks are mixed and bonded.

[0235] As described above, compound (A) has a cationic functional group comprising at least one of a primary nitrogen atom and a secondary nitrogen atom. Here, when compound (A) contains a primary nitrogen atom, the proportion of primary nitrogen atoms in all nitrogen atoms in compound (A) is preferably 20 mol% or more, more preferably 25 mol% or more, and even more preferably 30 mol% or more. Alternatively, compound (A) may have a cationic functional group comprising a primary nitrogen atom and excluding nitrogen atoms other than primary nitrogen atoms (e.g., secondary nitrogen atoms or tertiary nitrogen atoms).

[0236] When compound (A) contains secondary nitrogen atoms, the proportion of secondary nitrogen atoms in all nitrogen atoms in compound (A) is preferably 5 mol% to 50 mol%, more preferably 10 mol% to 45 mol%.

[0237] In addition, compound (A) may contain tertiary nitrogen atoms in addition to primary nitrogen atoms and secondary nitrogen atoms. When compound (A) contains tertiary nitrogen atoms, the proportion of tertiary nitrogen atoms in all nitrogen atoms in compound (A) is preferably greater than 20 mol% and less than 50 mol%, and more preferably greater than 25 mol% and less than 45 mol%.

[0238] In the present disclosure, the content of the component derived from compound (A) in the joint is not particularly limited. For example, it can be set to 1 mass % or more and 82 mass % or less, preferably 5 mass % or more and 82 mass % or less, and more preferably 13 mass % or more and 82 mass % or less, relative to the entire joint.

[0239] (Crosslinking agent (B))

[0240] The crosslinking agent (B) is a compound having three or more -C(=O)OX groups (X is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms) in the molecule, one or more and six or less of the three or more -C(=O)OX groups (hereinafter also referred to as "COOX") are -C(=O)OH groups (hereinafter also referred to as "COOH"), and a weight-average molecular weight of 200 to 600.

[0241] The crosslinking agent (B) is a compound having three or more -C(=O)OX groups (X is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms) in the molecule, preferably a compound having three or more to 6 -C(=O)OX groups in the molecule, and more preferably a compound having three or four -C(=O)OX groups in the molecule.

[0242] In the crosslinking agent (B), X in the -C(=O)OX group may be a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, with a hydrogen atom, a methyl group, an ethyl group, and a propyl group being preferred. It should be noted that X in the -C(=O)OX group may be the same or different.

[0243] The crosslinking agent (B) is a compound having one or more and six or less -C(=O)OH groups in which X is a hydrogen atom in the molecule, preferably a compound having one or more and four or less -C(=O)OH groups in the molecule, more preferably a compound having two or more and four or less -C(=O)OH groups in the molecule, and even more preferably a compound having two or three -C(=O)OH groups in the molecule.

[0244] The crosslinking agent (B) is a compound having a weight average molecular weight of 200 or more and 600 or less, preferably a compound having a weight average molecular weight of 200 or more and 400 or less.

[0245] The crosslinking agent (B) preferably has a ring structure in the molecule. Examples of the ring structure include alicyclic structures and aromatic ring structures. In addition, the crosslinking agent (B) may have multiple ring structures in the molecule, and the multiple ring structures may be the same or different.

[0246] Examples of the alicyclic structure include an alicyclic structure having 3 to 8 carbon atoms, preferably an alicyclic structure having 4 to 6 carbon atoms. The ring structure may be saturated or unsaturated. More specifically, examples of the alicyclic structure include saturated alicyclic structures such as a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, and a cyclooctane ring; and unsaturated alicyclic structures such as a cyclopropene ring, a cyclobutene ring, a cyclopentene ring, a cyclohexene ring, a cycloheptene ring, and a cyclooctene ring.

[0247] The aromatic ring structure is not particularly limited as long as it is a ring structure showing aromaticity. Examples thereof include benzene-based aromatic rings such as benzene ring, naphthalene ring, anthracene ring, and perylene ring; aromatic heterocycles such as pyridine ring and thiophene ring; and non-benzene-based aromatic rings such as indene ring and azulene ring.

[0248] The ring structure possessed by the crosslinking agent (B) in the molecule is preferably at least one selected from the group consisting of a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a benzene ring, and a naphthalene ring. From the perspective of further improving the heat resistance of the bonded portion, at least one of a benzene ring and a naphthalene ring is more preferred.

[0249] As described above, the crosslinking agent (B) may have a plurality of ring structures in the molecule. When the ring structure is benzene, the crosslinking agent (B) may have a biphenyl structure, a benzophenone structure, a diphenyl ether structure, or the like.

[0250] The crosslinking agent (B) preferably has a fluorine atom in the molecule, more preferably has 1 or more and 6 or less fluorine atoms in the molecule, and even more preferably has 3 or more and 6 or less fluorine atoms in the molecule. For example, the crosslinking agent (B) may have a fluoroalkyl group in the molecule, specifically a trifluoroalkyl group or a hexafluoroisopropyl group.

[0251] In addition, examples of the crosslinking agent (B) include carboxylic acid compounds such as alicyclic carboxylic acids, benzene carboxylic acids, naphthalene carboxylic acids, diphthalic acids, and fluorinated aromatic ring carboxylic acids; and carboxylate compounds such as alicyclic carboxylic acid esters, benzene carboxylic acid esters, naphthalene carboxylic acid esters, diphthalic acid esters, and fluorinated aromatic ring carboxylic acid esters. It should be noted that the carboxylate compound is a compound having a carboxyl group (-C(=O)OH group) in the molecule, and at least one X among three or more -C(=O)OX groups is an alkyl group having 1 or more and 6 or less carbon atoms (i.e., having an ester bond). In the present disclosure, since the crosslinking agent (B) is a carboxylate compound, the aggregation caused by the association of the compound (A) and the crosslinking agent (B) is suppressed, the number of aggregates and pits is reduced, and the adjustment of the film thickness becomes easy.

[0252] The carboxylic acid compound is preferably a tetravalent or less carboxylic acid compound containing four or less -C(=O)OH groups, and more preferably a trivalent or tetravalent carboxylic acid compound containing three or four -C(=O)OH groups.

[0253] The carboxylic acid ester compound preferably contains three or less carboxyl groups (—C(═O)OH groups) and three or less ester bonds in the molecule, and more preferably contains two or less carboxyl groups and two or less ester bonds in the molecule.

[0254] In the aforementioned carboxylate compound, when X in three or more -C(=O)OX groups is an alkyl group having 1 to 6 carbon atoms, X is preferably a methyl group, an ethyl group, a propyl group, a butyl group, or the like. From the perspective of further suppressing aggregation caused by the association of the compound (A) and the crosslinking agent (B), an ethyl group or a propyl group is preferred.

[0255] Specific examples of the carboxylic acid compound include, but are not limited to, alicyclic carboxylic acids such as 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, and 1,2,3,4,5,6-cyclohexanehexacarboxylic acid; phenylcarboxylic acids such as 1,2,4-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, pyromellitic acid, benzenepentacarboxylic acid, and mellitic acid; naphthalenetetracarboxylic acid such as 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, and the like. Carboxylic acids; 3,3',5,5'-tetracarboxydiphenylmethane, biphenyl-3,3',5,5'-tetracarboxylic acid, biphenyl-3,4',5-tricarboxylic acid, biphenyl-3,3',4,4'-tetracarboxylic acid, benzophenone-3,3',4,4'-tetracarboxylic acid, 4,4'-oxydiphthalic acid, 3,4'-oxydiphthalic acid, 1,3-bis(phthalic acid)tetramethyldisiloxane, 4,4'-(Ethyne-1,2-diyl)diphthalic acid acid), 4,4'-(1,4-phenylenebis(oxy))diphthalic acid, 4,4'-([1,1'-biphenyl]-4,4'-diylbis(oxy))diphthalic acid, 4,4'-((oxybis(4,1-phenylene))bis(oxy))diphthalic acid perylenecarboxylic acids such as perylene-3,4,9,10-tetracarboxylic acid; anthracenecarboxylic acids such as anthracene-2,3,6,7-tetracarboxylic acid; fluorinated aromatic ring carboxylic acids such as 4,4'-(hexafluoroisopropylidene)diphthalic acid, 9,9-bis(trifluoromethyl)-9H-xanthene-2,3,6,7-tetracarboxylic acid, and 1,4-bis(trifluoromethyl)pyromellitic acid.

[0256] Specific examples of the carboxylic acid ester compound include compounds in which at least one carboxyl group in the specific examples of the carboxylic acid compound is substituted with an ester group. Examples of the carboxylic acid ester compound include half-esterified compounds represented by the following general formulas (B-1) to (B-5).

[0257] [Chemistry 2]

[0258]

[0259] R in general formulae (B-1) to (B-5) is independently an alkyl group having 1 to 6 carbon atoms, preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and more preferably an ethyl group or a propyl group.

[0260] Y in the general formula (B-2) is a single bond, O, C=O, or C(CF 3 ) 2 , and is preferably O.

[0261] The half-esterified compound can be produced by, for example, mixing carboxylic acid anhydride, which is the anhydride of the aforementioned carboxylic acid compound, with an alcohol solvent and ring-opening the carboxylic acid anhydride.

[0262] The content of the component from the cross-linking agent (B) in the organic gap filling material is not particularly limited. For example, the ratio of the number of carbonyl groups (-(C=O)-Y) in the substance from the cross-linking agent (B) to the number of all nitrogen atoms in the substance from the compound (A) ((-(C=O)-Y) / N) is preferably 0.1 or more and 3.0 or less, more preferably 0.3 or more and 2.5 or less, and further preferably 0.4 or more and 2.2 or less. Here, in -(C=O)-Y, Y represents a nitrogen atom, OH or ester group cross-linked by imide or amide. By making -(C=O)-Y / N 0.1 or more and 3.0 or less, the joint portion suitably has a cross-linked structure such as amide, amideimide, or imide, and the heat resistance is more excellent.

[0263] It is believed that because compound (A) has uncrosslinked cationic functional groups, when the bonding portion comprises compound (A) and does not comprise a crosslinking agent (B), the crosslinking density is low and the heat resistance is insufficient. On the other hand, in an organic gap-filling material, the cationic functional groups of compound (A) react with the carboxyl groups of the crosslinking agent (B) to form covalent bonds, thereby increasing the crosslinking density and providing high heat resistance.

[0264] (Polar solvent (D))

[0265] Specific examples of the polar solvent (D) include:

[0266] Protic inorganic compounds such as water and heavy water;

[0267] Methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, isopentanol, cyclohexanol, ethylene glycol, propylene glycol, 2-methoxyethanol, 2-ethoxyethanol, benzyl alcohol, diethylene glycol, triethylene glycol, glycerol and other alcohols;

[0268] Ethers such as tetrahydrofuran and dimethoxyethane;

[0269] Furfural, acetone, methyl ethyl ketone, cyclohexane and other aldehydes / ketones;

[0270] Acid derivatives such as acetic anhydride, ethyl acetate, butyl acetate, ethylene carbonate, propylene carbonate, formaldehyde, N-methylformamide, N,N-dimethylformamide, N-methylacetamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and hexamethylphosphoramide;

[0271] Nitriles such as acetonitrile and propionitrile; nitro compounds such as nitromethane and nitrobenzene;

[0272] Sulfur compounds such as dimethyl sulfoxide.

[0273] As the polar solvent (D), a protic solvent is preferably contained, water is more preferably contained, and ultrapure water is further preferably contained.

[0274] The content of the polar solvent (D) in the solution is not particularly limited, and is, for example, 1.0% by mass to 99.99896% by mass, and preferably 40% by mass to 99.99896% by mass, based on the entire solution.

[0275] From the viewpoint of volatilizing the polar solvent (D) by heating during formation of the organic gap-filling material and reducing the amount of residual solvent in the organic gap-filling material, the boiling point of the polar solvent (D) is preferably 150° C. or lower, more preferably 120° C. or lower.

[0276] (Additive (C))

[0277] The solution containing the resin material may contain an additive (C).

[0278] Examples of the additive (C) include an acid (C-1) having a carboxyl group and a weight average molecular weight of 46 to 195, and a base (C-2) having a nitrogen atom and a weight average molecular weight of 17 to 120 without a ring structure.

[0279] Acid (C-1) is an acid having a weight average molecular weight of 46 or more and 195 or less having a carboxyl group. It is speculated that by including acid (C-1) as additive (C), the amino group in compound (A) and the carboxyl group in acid (C-1) form an ionic bond, thereby suppressing the aggregation caused by the association of compound (A) and cross-linking agent (B). In more detail, it is speculated that the interaction (for example, electrostatic interaction) between the ammonium ion from the amino group in compound (A) and the carboxyl ion from the carboxyl group in acid (C-1) is stronger than the interaction between the ammonium ion from the amino group in compound (A) and the carboxyl ion from the carboxyl group in cross-linking agent (B), thereby suppressing aggregation. In addition, the present invention is not limited by the above speculation.

[0280] The acid (C-1) is not particularly limited as long as it is a compound having a carboxyl group and a weight-average molecular weight of 46 to 195, and examples thereof include monocarboxylic acid compounds, dicarboxylic acid compounds, and hydroxydicarboxylic acid compounds. More specifically, examples of the acid (C-1) include formic acid, acetic acid, malonic acid, oxalic acid, citric acid, benzoic acid, lactic acid, glycolic acid, glyceric acid, butyric acid, methoxyacetic acid, ethoxyacetic acid, phthalic acid, terephthalic acid, picolinic acid, salicylic acid, and 3,4,5-trihydroxybenzoic acid.

[0281] In the present disclosure, the content of the acid (C-1) in the solution containing the resin material is not particularly limited. For example, the ratio of the number of carboxyl groups in the acid (C-1) to the number of all nitrogen atoms in the compound (A) (COOH / N) is preferably 0.01 or more and 10 or less, more preferably 0.02 or more and 6 or less, and even more preferably 0.5 or more and 3 or less.

[0282] Base (C-2) is a base having a weight average molecular weight of 17 or more and 120 or less having nitrogen atoms. It is speculated that by including base (C-2) as an additive (C) in the solution containing the resin material, the carboxyl group in the crosslinker (B) and the amino group in the base (C-2) form an ionic bond, thereby suppressing the aggregation caused by the association of compound (A) and crosslinker (B). More specifically, it is speculated that the interaction between the carboxyl group-derived carboxyl group in the crosslinker (B) and the ammonium ion derived from the amino group in the base (C-2) is stronger than the interaction between the ammonium ion derived from the amino group in the compound (A) and the carboxyl group-derived carboxyl group in the crosslinker (B), and thus aggregation is suppressed. In addition, the present invention is not limited by the above speculation.

[0283] The base (C-2) is not particularly limited as long as it is a compound having a nitrogen atom, a weight average molecular weight of 17 or more and 120 or less, and does not have a ring structure, and examples thereof include monoamine compounds and diamine compounds. More specifically, examples of the base (C-2) include ammonia, ethylamine, ethanolamine, diethylamine, triethylamine, ethylenediamine, N-acetylethylenediamine, N-(2-aminoethyl)ethanolamine, and N-(2-aminoethyl)glycine.

[0284] In the present disclosure, the content of the base (C-2) in the solution containing the resin material is not particularly limited. For example, the ratio of the number of nitrogen atoms in the base (C-2) to the number of carboxyl groups in the cross-linking agent (B) (N / COOH) is preferably 0.5 or more and 5 or less, and more preferably 0.9 or more and 3 or less.

[0285] In the solution containing the resin material, in order to improve insulation or mechanical strength, tetraethoxysilane, tetramethoxysilane, bis(triethoxysilyl)ethane, bis(triethoxysilyl)methane, bis(methyldiethoxysilyl)ethane, 1,1,3,3,5,5-hexaethoxy-1,3,5-trisilacyclohexane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahydroxycyclosiloxane, 1,1,4,4-tetramethyl-1,4-diethoxydisilylethylene, and 1,3,5-trimethyl-1,3,5-trimethyl-1,3,5-triethoxy-1,3,5-trisilacyclohexane may be mixed.

[0286] Furthermore, in order to improve the hydrophobicity of the organic gap filler material, methyltriethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, etc. may be mixed in order to control the etching selectivity.

[0287] The solution containing the resin material may contain a solvent other than the polar solvent (D), and examples thereof include n-hexane.

[0288] Furthermore, for example, in order to improve electrical characteristics, the solution containing the resin material may contain phthalic acid, benzoic acid, or the like, or derivatives thereof.

[0289] In addition, in order to suppress corrosion of, for example, copper, the solution containing the resin material may contain benzotriazole or a derivative thereof.

[0290] The pH of the solution containing the resin material is not particularly limited, but is preferably 2.0 or more and 12.0 or less.

[0291] When an acid (C-1) is used as the additive (C), it is preferable to mix the mixture of the acid (C-1) and the compound (A) with the crosslinking agent (B). Specifically, it is preferable to mix the compound (A) and the acid (C-1) before mixing them. This can preferably suppress turbidity and gelation of the solution containing the resin layer-forming material when the compound (A) and the crosslinking agent (B) are mixed (gelation may take time to clear the composition, which is undesirable).

[0292] When a base (C-2) is used as the additive (C), it is preferred to mix a mixture of the base (C-2) and the crosslinking agent (B) with the compound (A). Specifically, it is preferred to mix the crosslinking agent (B) and the base (C-2) before mixing the compound (A) and the crosslinking agent (B). This can preferably suppress turbidity and gelation of the solution containing the resin layer-forming material when the compound (A) and the crosslinking agent (B) are mixed (gelation may take time to clear the composition, which is unsatisfactory).

[0293] <Silicon-Containing Layer>

[0294] The semiconductor structure of the present disclosure (e.g., semiconductor structure 100) may further include a silicon-containing layer (e.g., silicon-containing layer 32) at least interposed between the organic gap-filling material (e.g., organic gap-filling material 30) and the semiconductor substrate (e.g., bonding layer 14 in semiconductor substrate 10). This further improves the adhesion between the organic gap-filling material and the semiconductor substrate.

[0295] The silicon-containing layer may be at least between the organic gap filling material and the semiconductor substrate, and between the organic gap filling material (for example, referring to Figure 1 As a result, the adhesion between the organic gap-filling material and the semiconductor substrate, and the adhesion between the organic gap-filling material and the silicon crystal grains are further improved.

[0296] The silicon-containing layer preferably includes at least one selected from the group consisting of a SiO 2 layer, a SiCN layer, a SiN layer, and a resin layer containing a siloxane bond.

[0297] (SiO2 layer, SiCN layer, SiN layer)

[0298] As the SiO 2 layer, the SiCN layer, and the SiN layer including the silicon, known layers formed by a vapor phase growth method such as sputtering, CVD, or ALD can be applied.

[0299] (Siloxane bond-containing resin layer)

[0300] The resin layer containing siloxane bonds as the silicon-containing layer can be formed by a wet process such as a coating method (eg, a method including coating and heating) or a printing method.

[0301] Preferred aspects of the method for forming the resin layer containing a siloxane bond are the same as those of the method for forming the organic gap-filling material.

[0302] The resin layer containing a siloxane bond as the silicon-containing layer includes, for example, structures represented by the following formulae (1) to (3).

[0303] [Chemistry 3]

[0304]

[0305] In a structure having a Si-O bond (siloxane bond), the group bonded to Si may be substituted by an alkylene group, a phenylene group, or the like. For example, a group having (-O-) x (R1) y Si-(R2)-Si(R1) y (-O-) xetc. (R1 represents a methyl group, etc., R2 represents an alkylene group, a phenylene group, etc., x and y are each independently an integer greater than 0, and x+y is 3).

[0306] Examples of materials for forming Si—O bonds include compounds represented by the following formulae (4) and (5).

[0307] Furthermore, the structures represented by formula (1) and formula (2) can be produced by, for example, heating the compounds represented by formula (4) and formula (5) to cause them to react.

[0308] [Chemistry 4]

[0309]

[0310] Examples of coating solutions for forming a resin layer containing a siloxane bond include those using a compound having a Si—O bond and an amino group as the compound (A) in the aforementioned coating solution for forming an organic gap-filling material.

[0311] Examples of the compound having a Si—O bond and an amino group include siloxane diamine, a silane coupling agent having an amino group, and a siloxane polymer of a silane coupling agent having an amino group.

[0312] As a silane coupling agent which has an amino group, the compound represented by following formula (A-3) is mentioned, for example.

[0313] [Chemistry 5]

[0314]

[0315] In formula (A-3), R 1 represents an alkyl group having 1 to 4 carbon atoms which may be substituted. 2 and R 3 Each independently represents an alkylene group having 1 to 12 carbon atoms, an ether group or a carbonyl group which may be substituted (a carbonyl group, an ether group or the like may be contained in the skeleton). 4 and R 5 Each independently represents an optionally substituted alkylene group having 1 to 4 carbon atoms or a single bond. Ar represents a divalent or trivalent aromatic ring. 1 represents hydrogen or an optionally substituted alkyl group having 1 to 5 carbon atoms. 2 represents hydrogen, a cycloalkyl group, a heterocyclic group, an aryl group, or an alkyl group having 1 to 5 carbon atoms which may be substituted (the skeleton may contain a carbonyl group, an ether group, etc.). 1 、R 2 、R 3 、R 4 、R 5 、X 1 Can be the same or different.

[0316] As R 1 、R 2 、R 3 、R 4 、R 5 、X 1 、X 2 The substituents of the alkyl group and the alkylene group in the group include, independently, amino, hydroxy, alkoxy, cyano, carboxylic acid, sulfonic acid, halogen and the like.

[0317] Examples of the divalent or trivalent aromatic ring in Ar include a divalent or trivalent benzene ring. 2 Examples of the aryl group include a phenyl group, a methylbenzyl group, and a vinylbenzyl group.

[0318] Specific examples of the silane coupling agent represented by formula (A-3) include N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminoisobutyldimethylmethoxysilane, N-(2-aminoethyl)-3-aminoisobutylmethyldimethoxysilane, N-(2-aminoethyl)-11-aminoundecyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, (aminoethylaminoethyl)phenyltriethoxysilane, methylbenzylaminoethylaminopropyltrimethoxysilane, benzylaminoethylaminopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, alkyl, (aminoethylaminoethyl)phenethyltrimethoxysilane, (aminoethylaminomethyl)phenethyltrimethoxysilane, N-[2-[3-(trimethoxysilyl)propylamino]ethyl]ethylenediamine, 3-aminopropyldiethoxymethylsilane, 3-aminopropyldimethoxymethylsilane, 3-aminopropyldimethylethoxysilane, 3-aminopropyldimethylmethoxysilane, trimethoxy[2-(2-aminoethyl)-3-aminopropyl]silane, diaminomethylmethyldiethoxysilane, methylaminomethylmethyldiethoxysilane, p-aminophenyltrimethoxysilane, N-methylaminopropyltriethoxysilane, N-methylaminopropylmethyldiethoxysilane, (phenylaminomethyl)methyldiethoxysilane, acetamidopropyltrimethoxysilane and hydrolyzates thereof.

[0319] Examples of amino group-containing silane coupling agents other than those represented by formula (A-3) include N,N-bis[3-(trimethoxysilyl)propyl]ethylenediamine, N,N′-bis[3-(trimethoxysilyl)propyl]ethylenediamine, bis[(3-triethoxysilyl)propyl]amine, piperazinylpropylmethyldimethoxysilane, bis[3-(triethoxysilyl)propyl]urea, bis(methyldiethoxysilylpropyl)amine, 2,2-dimethoxy-1,6-diaza-2-silacyclooctane, 3,5-diamino-N-(4-(methoxydimethylsilyl)phenyl)benzamide, 3,5-diamino-N-(4-(triethoxysilyl)phenyl)benzamide, 5-(ethoxydimethylsilyl)benzene-1,3-diamine, and hydrolyzates thereof.

[0320] The aforementioned silane coupling agent having an amino group may be used alone or in combination of two or more. In addition, a silane coupling agent having an amino group and a silane coupling agent not having an amino group may also be used in combination. For example, a silane coupling agent having a mercapto group may be used to improve adhesion to metals.

[0321] In addition, polymers (siloxane polymers) formed from these silane coupling agents via siloxane bonds (Si—O—Si) can also be used. For example, polymers having a linear siloxane structure, a branched siloxane structure, a cyclic siloxane structure, and a cage siloxane structure can be obtained from the hydrolyzate of 3-aminopropyltrimethoxysilane. The cage siloxane structure is represented, for example, by the following formula (A-1).

[0322] [Chemistry 6]

[0323]

[0324] Examples of the siloxane diamine include compounds represented by the following formula (A-2): In formula (A-2), i is an integer of 0 to 4, j is an integer of 1 to 3, and Me is a methyl group.

[0325] [Chemistry 7]

[0326]

[0327] Examples of the siloxane diamine include 1,3-bis(3-aminopropyl)tetramethyldisiloxane (in formula (A-2), i=0, j=1) and 1,3-bis(2-aminoethylamino)propyltetramethyldisiloxane (in formula (A-2), i=1, j=1).

[0328] The entire disclosure of Japanese Patent Application No. 2023-016420 filed on February 6, 2023 is incorporated into this specification by reference.

[0329] All documents, patent applications, and technical standards described in this specification are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference.

Claims

1. A semiconductor structure comprising: semiconductor substrates, a plurality of silicon grains disposed on the semiconductor substrate and hybrid-bonded with the semiconductor substrate; and An organic gap-filling material is filled between the plurality of silicon grains on the semiconductor substrate.

2. The semiconductor structure according to claim 1, wherein The semiconductor substrate and the plurality of silicon crystal grains each include a bonding layer including an insulating layer and an electrode. The bonding layer in the semiconductor substrate is hybrid-bonded with the bonding layers in the plurality of silicon grains.

3. The semiconductor structure according to claim 2, wherein: The insulating layer includes at least one selected from the group consisting of a SiO 2 layer, a SiCN layer, a SiN layer, and a resin layer containing a siloxane bond. The semiconductor structure according to claim 1 , wherein: The organic gap-filling material includes at least one selected from the group consisting of polyimide, polyamide, polyamideimide, maleimide resin, parylene, polyarylene ether polyimide, polybenzoxazole, benzocyclobutene resin, and epoxy resin. The semiconductor structure according to claim 1 , wherein: The organic gap-filling material includes a resin having a siloxane bond. The semiconductor structure according to claim 1 , further comprising a silicon-containing layer at least interposed between the organic gap-filling material and the semiconductor substrate.

7. The semiconductor structure according to claim 6, wherein: The silicon-containing layer includes at least one selected from the group consisting of a SiO 2 layer, a SiCN layer, a SiN layer, and a resin layer containing a siloxane bond.

8. A method for manufacturing a semiconductor structure, which is a method for manufacturing the semiconductor structure according to any one of claims 1 to 5, comprising: The process of temporarily fixing a plurality of silicon crystal grains on a first temporary fixing substrate, forming an organic gap-filling material on the side of the first temporary fixing substrate where the plurality of silicon crystal grains are temporarily fixed, thereby filling the organic gap-filling material between the plurality of silicon crystal grains; a step of temporarily fixing a second temporary fixing substrate to the side of the first temporary fixing substrate on which the organic gap-filling material is formed to obtain a laminate X1; a step of removing the first temporary fixing substrate from the stacked body X1 to obtain a stacked body X2 in which the plurality of silicon crystal grains are exposed; performing at least one of cleaning and polishing on the exposed surfaces of the plurality of silicon crystal grains in the stacked body X2, a step of hybrid bonding a semiconductor substrate and the exposed surfaces of the plurality of silicon crystal grains subjected to at least one of the cleaning and polishing to obtain a laminate X3; and A step of obtaining the semiconductor structure by removing the second temporary fixing substrate from the stacked body X3.

9. The method for manufacturing a semiconductor structure according to claim 8, further comprising: After the process of temporarily fixing the multiple silicon grains on the first temporarily fixed substrate and before the process of filling the organic gap filling material between the multiple silicon grains, a silicon-containing layer is formed on the side of the first temporarily fixed substrate to which the multiple silicon grains are temporarily fixed, thereby covering at least the exposed surface of the first temporarily fixed substrate with the silicon-containing layer.

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