Structure and method of manufacturing the same

Abstract

To provide a structure capable of adapting to a new semiconductor package mounting technology.SOLUTION: A structure comprises first and second members, and an insulation member that is arranged at a peripheral edge of a space between the first and second members.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a structure and a manufacturing method thereof. [Background technology]

[0002] In the mounting technology of semiconductor packages, resin materials called underfill materials for filling the gap between the substrate and the element, molding materials for covering the outer periphery of the element, etc. are used. Improvements in the physical properties of these resin materials are being studied to meet the requirements according to the intended use. For example, Patent Document 1 describes an underfill material that contains an aminophenol-type epoxy resin to suppress the increase in the thermal expansion coefficient after curing and reduce the viscosity during filling. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-011409 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, with the spread of 5th generation mobile communication standard (5G) technology, new issues have arisen in the mounting technology of semiconductor packages used in communication devices, etc. For example, it has been pointed out that the resin materials that have been used traditionally may cause a decrease in the transmission efficiency of high frequency radio waves, resulting in communication delays, etc.

[0005] In view of the above circumstances, an object of the present disclosure is to provide a structure that is compatible with new semiconductor package mounting techniques and a manufacturing method thereof. [Means for solving the problem]

[0006] <1> A structure comprising a first member, a second member, and an insulating member disposed on the periphery of a space between the first member and the second member. <2> The insulating member is a cured product of a curable resin composition. <1> The structure described in <3> The curable resin composition includes an epoxy resin. <2> The structure described in <4> The first member is a support and the second member is a semiconductor element. <1> ~ <3> 2. The structure according to any one of claims 1 to 11. <5> The method includes disposing a curable resin composition on a peripheral portion of a space between a first member and a second member, and curing the curable resin composition. <1> ~ <4> 13. A method for producing the structure according to any one of claims 1 to 12. Effect of the Invention

[0007] According to the present invention, a structure that can accommodate new semiconductor package mounting techniques and a method for manufacturing the same are provided. [Brief description of the drawings]

[0008] [Figure 1] 4A to 4C are cross-sectional views each showing a schematic example of the shape of an insulating member. [Diagram 2] 4A to 4C are cross-sectional views each showing a schematic example of the shape of an insulating member. [Diagram 3] 4A to 4C are cross-sectional views each showing a schematic example of the shape of an insulating member. [Figure 4] 1A to 1C are plan views each showing a schematic example of a shape of an insulating member. [Diagram 5] 1A to 1C are plan views each showing a schematic example of a shape of an insulating member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiment for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiment. In the following embodiment, the components (including element steps, etc.) are not essential unless specifically stated. The same applies to the numerical values ​​and their ranges, and they do not limit the present invention.

[0010] In the present disclosure, the term "step" includes not only a step that is independent of other steps, but also a step that cannot be clearly distinguished from other steps as long as the purpose of the step is achieved. In the present disclosure, a numerical range indicated using "~" includes the numerical values ​​before and after "~" as the minimum and maximum values, respectively. In the numerical ranges described in the present disclosure in stages, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. In addition, in the numerical ranges described in the present disclosure, the upper or lower limit value of the numerical range may be replaced with a value shown in the examples. In the present disclosure, each component may contain multiple types of the corresponding substance. When multiple substances corresponding to each component are present in the composition, the content or amount of each component means the total content or amount of the multiple substances present in the composition, unless otherwise specified. In the present disclosure, the particles corresponding to each component may include multiple types. When multiple types of particles corresponding to each component are present in the composition, the particle size of each component means the value for a mixture of the multiple types of particles present in the composition, unless otherwise specified.

[0011] <Structure> The structure of the present disclosure includes a first member, a second member, and an insulating member disposed on the periphery of a space between the first member and the second member.

[0012] In this disclosure, "periphery of the space between a first member and a second member" means the portion corresponding to the outline of the area sandwiched between the first member and the second member or its vicinity (which may be either the inside or the outside of the area, or both).

[0013] By applying the above-described structure to the manufacture of semiconductor packages, the following effects can be expected, for example. (1) If the periphery of the space between the opposing components is joined with an insulating material and the inside is not filled with resin, the inside of the periphery is filled with air, which has a lower dielectric constant than resin. As a result, the transmission efficiency of high-frequency radio waves is less likely to decrease, and communication delays and other issues are suppressed. (2) Inside a semiconductor package, the edges of opposing components are more likely to be subjected to stress than the center. By disposing the insulating material on the edges, the insulating material functions as a buffer material, effectively reducing the stress on the edges. (3) An insulating material can be placed on the periphery of the space between the opposing components, and a different material can be used to fill the inside. This makes it possible to select materials according to the location between the opposing components. For example, materials can be selected for the periphery of the space between the opposing components, taking into account their mechanical properties, and materials can be selected for the filling on the inside, taking into account their dielectric constant.

[0014] In the structure, the shape of the insulating member disposed on the periphery of the space between the first member and the second member is not particularly limited. Figures 1 to 3 are cross-sectional views that typically show specific examples of the shape of the insulating member. The shape of the insulating member may be a shape that contacts the surface of the first member 1, the side surface of the second member 2, and the back surface of the second member 2 (the surface on the first member side) as shown in Figure 1, a shape that contacts the surface of the first member and the side surface of the second member as shown in Figure 2, or a shape that contacts the surface of the first member 1 and the back surface of the second member 2 as shown in Figure 3.

[0015] The insulating member may be disposed over the entire periphery of the space between the members, or may be disposed partially. Figures 4 and 5 are plan views that show schematic examples of the shape of the insulating member. The insulating member may be disposed continuously over the periphery of the space between the members as shown in Figure 4, or may be disposed discontinuously over the periphery of the space between the members as shown in Figure 5.

[0016] The distance between the first member and the second member (if the distance is not constant, the distance at the periphery of the space) is not particularly limited and can be selected according to the size, type, etc. of the structure. For example, it can be selected from the range of 50 μm to 1000 μm. The height of the insulating member is not particularly limited and can be selected depending on the size, type, etc. of the structure, and can be selected, for example, from the range of 50 μm to 1000 μm. The width of the insulating member is not particularly limited and can be selected depending on the size, type, etc. of the structure, and can be selected, for example, from the range of 50 μm to 1000 μm.

[0017] The types of the first member and the second member in the structure are not particularly limited and can be selected according to the application of the structure, etc. For example, the first member may be a support and the second member may be a semiconductor element.

[0018] The type of insulating member in the structure is not particularly limited and can be selected according to the application of the structure. From the viewpoint of mechanical strength, heat resistance, etc., the insulating member is preferably a cured product of a curable resin composition. In the present disclosure, the curable resin composition means a composition containing at least a curable resin and other components according to the necessity.

[0019] Specific examples of the curable resin contained in the curable resin composition include thermosetting resins such as epoxy resins, phenolic resins, melamine resins, and unsaturated polyester resins, and ultraviolet-curable resins such as acrylic resins. Among these, epoxy resins are preferred.

[0020] From the viewpoint of forming an insulating member of a desired shape on the periphery of the space, the insulating member is preferably a cured product of a curable resin having a thixotropic index of 1.0 or more in the range of 25°C to 50°C. A curable resin having a thixotropic index of 1.0 or more in the range of 25°C to 50°C is unlikely to change the shape immediately after applying the curable resin composition to a desired region on the periphery of the space between members even if the viscosity is reduced by heating for curing, etc., and a cured product having a shape similar to that immediately after application can be obtained. In addition, the process of applying the curable resin composition can be performed in a room temperature environment, and it is easy to handle.

[0021] In the present disclosure, "the thixotropic index at 25°C to 50°C is 1.0 or more" means that the thixotropic index is 1.0 or more at any temperature between 25°C and 50°C.

[0022] From the viewpoint of shape retention, the thixotropic index of the curable resin composition at 25°C to 50°C is preferably 1.2 or more, more preferably 1.5 or more, and even more preferably 1.7 or more. There is no particular upper limit for the thixotropic index of the edge bond material in the range of 25° C. to 50° C. For example, it may be 5.0 or less.

[0023] The thixotropic index of the curable resin composition is measured by the method described in the Examples.

[0024] From the viewpoint of forming an insulating member of a desired shape on the periphery of the space, the insulating member is preferably a cured product of a curable resin composition that is liquid in the range of 25°C to 50°C. The curable resin composition, which is liquid in the range of 25° C. to 50° C., can be easily applied to a desired region of the periphery of the space between members. In addition, by curing the curable resin composition after application, a structure in which the periphery of the space between members is joined with a cured product of the curable resin composition can be easily formed.

[0025] In the present disclosure, "being liquid in the range of 25°C to 50°C" means being liquid at any temperature between 25°C and 50°C.

[0026] The viscosity of the curable resin composition at 25° C. to 50° C. is preferably 10 Pa·s or more, more preferably 20 Pa·s or more, and even more preferably 30 Pa·s or more. When the viscosity of the curable resin composition at 25° C. to 50° C. is 10 Pa·s or more, the edge bond material is applied to a desired portion of a substrate or the like and then allowed to stand, so that the original shape is likely to be maintained.

[0027] The viscosity of the curable resin composition at 25° C. is preferably 300 Pa·s or less, more preferably 250 Pa·s or less, and even more preferably 230 Pa·s or less. When the viscosity of the curable resin composition at 25°C is 300 Pa s or less, the curable resin composition can be applied to a desired portion of a substrate or the like using a dispenser, a screen printer, an inkjet printer, or the like, and the workability is excellent.

[0028] The viscosity of the curable resin composition at 50° C. is not particularly limited as long as the thixotropic index at 50° C. is 1.5 or more. For example, it may be 200 Pa s or less, 180 Pa s or less, or 150 Pa s or less.

[0029] The viscosity of the curable resin composition is measured by the method described in the Examples.

[0030] The properties of the cured product of the curable resin composition are not particularly limited and can be selected depending on the application of the structure, etc.

[0031] From the viewpoint of reliability, the coefficient of thermal expansion (CTE1) of the cured product of the curable resin composition is preferably 25 ppm / ° C. or less, more preferably 22 ppm / ° C. or less, and even more preferably 20 ppm / ° C. or less. The coefficient of thermal expansion (CTE2) of the cured product of the curable resin composition is preferably 80 ppm / ° C. or less, more preferably 75 ppm / ° C. or less, and even more preferably 70 ppm / ° C. or less.

[0032] From the viewpoint of heat resistance, the glass transition temperature (Tg) of the cured product of the curable resin composition is preferably 100° C. or higher, more preferably 120° C. or higher, and even more preferably 140° C. or higher.

[0033] In the present disclosure, the thermal expansion coefficient and glass transition temperature of the cured product of the curable resin composition are measured as follows. The liquid encapsulating resin composition thus prepared is cured at 120° C. for 15 minutes to obtain a cured product, which is then cut into a size of 8 mm in diameter and 20 mm in length to prepare a measurement sample. Using a thermomechanical analyzer (TMA2940, manufactured by TA Instruments), the change in length (linear expansion coefficient) of the sample was measured by the compression method when the temperature was raised from 0°C to 240°C at a rate of 5°C / min, and the average linear expansion coefficient in the measurement temperature range of 10°C to 30°C was taken as CTE1, and the average linear expansion coefficient in the measurement temperature range of 180°C to 200°C was taken as CTE2. The temperature corresponding to the intersection of the tangents at 100°C and 200°C was determined as the glass transition temperature.

[0034] The temperature at which the curable resin composition is cured (curing temperature) is not particularly limited, and from the viewpoint of workability, it is preferably 200° C. or lower, more preferably 170° C. or lower, and even more preferably 150° C. or lower. It is also preferably 80° C. or higher, more preferably 90° C. or higher, and even more preferably 100° C. or higher.

[0035] Hereinafter, as an example of the curable resin composition, an epoxy resin composition containing an epoxy resin and a curing agent will be described. The types of epoxy resin and curing agent contained in the epoxy resin composition are not particularly limited and can be selected depending on the desired physical properties, etc.

[0036] The epoxy resin composition may contain a combination of an epoxy resin and a curing agent that are liquid at 25° C. and a curing agent that are solid at 25° C. For example, the epoxy resin composition may contain an epoxy resin that is liquid at 25° C. and a curing agent that is solid at 25° C. By using a combination of an epoxy resin and a curing agent that are liquid at 25° C. and a curing agent that are solid at 25° C., it tends to be easier to obtain an epoxy resin composition that is liquid in the range of 25° C. to 50° C. and has a thixotropic index of 1.0 or more in the range of 25° C. to 50° C.

[0037] [Epoxy resin] The type of epoxy resin contained in the epoxy resin composition is not particularly limited. For example, bisphenol type epoxy resin, naphthalene type epoxy resin, glycidylamine type epoxy resin, hydrogenated bisphenol type epoxy resin, alicyclic epoxy resin, alcohol ether type epoxy resin, cyclic aliphatic type epoxy resin, fluorene type epoxy resin, and siloxane type epoxy resin can be mentioned. The epoxy resin may be used alone or in combination of two or more kinds.

[0038] Among the above epoxy resins, bisphenol type epoxy resins and glycidylamine type epoxy resins are preferred from the viewpoint of the balance of properties of the epoxy resin composition.

[0039] Specific examples of bisphenol type epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AD ​​type epoxy resins, etc. Among these, bisphenol type epoxy resins that are liquid at 25° C. are preferred, and bisphenol F type epoxy resins that are liquid at 25° C. are more preferred. An example of a commercially available bisphenol F type epoxy resin that is liquid at 25°C is "Epotohto YDF-8170C" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.

[0040] When the epoxy resin composition contains a bisphenol-type epoxy resin, its proportion in the entire epoxy resin is not particularly limited and can be selected according to the desired properties of the epoxy resin composition. For example, it may be 30% by mass to 100% by mass, 40% by mass to 90% by mass, or 50% by mass to 70% by mass of the entire epoxy resin.

[0041] Specific examples of the glycidylamine type epoxy resin include diglycidylamine type epoxy resins, trifunctional or higher functional glycidylamine type epoxy resins, etc. Among these, glycidylamine type epoxy resins that are liquid at 25° C. are preferred, and glycidylamine type epoxy resins that are liquid at 25° C. or higher functional are more preferred.

[0042] An example of a glycidylamine type epoxy resin that is liquid at 25° C. is triglycidyl-p-aminophenol. Commercially available triglycidyl-p-aminophenol products include “jER-630” and “jER-630LSD” from Mitsubishi Chemical Corporation, and “EP-3950S” from ADEKA Corporation.

[0043] When the epoxy resin composition contains a glycidylamine type epoxy resin, the proportion of the glycidylamine type epoxy resin in the entire epoxy resin is not particularly limited and can be selected according to the desired properties of the edge bond material. For example, it may be 10% by mass to 100% by mass, 20% by mass to 70% by mass, or 30% by mass to 50% by mass of the entire epoxy resin.

[0044] [Hardening agent] The type of curing agent contained in the epoxy resin composition is not particularly limited. For example, amine curing agent, phenol curing agent, acid anhydride curing agent, polymercaptan curing agent, polyaminoamide curing agent, isocyanate curing agent, blocked isocyanate curing agent, etc. may be mentioned. The curing agent may be used alone or in combination of two or more kinds.

[0045] Among the above epoxy resins, the amine curing agent is preferred from the viewpoint of the balance of properties of the epoxy resin composition. Examples of the amine curing agent include aliphatic amine compounds such as diethylenetriamine, triethylenetetramine, n-propylamine, 2-hydroxyethylaminopropylamine, cyclohexylamine, and 4,4'-diamino-dicyclohexylmethane; aromatic amine compounds such as diethyltoluenediamine, 3,3'-diethyl-4,4'-diaminodiphenylmethane, and 2-methylaniline; imidazole compounds such as imidazole, 2-methylimidazole, 2-ethylimidazole, and 2-isopropylimidazole; and imidazoline compounds such as imidazoline, 2-methylimidazoline, and 2-ethylimidazoline.

[0046] The curing agent contained in the epoxy resin composition may be liquid at 25° C. or may be solid at 25° C. From the viewpoint of the balance between the ease of application using a dispenser, a screen printer, an inkjet printer, or the like, and the shape retention, it is preferable to use a curing agent that is solid at 25° C., and it is more preferable to use an amine curing agent that is solid at 25° C.

[0047] Examples of the amine curing agent that is solid at 25° C. include the above-mentioned aliphatic amine compounds. Examples of commercially available amine curing agents that are solid at 25° C. include “Fujicure FXR-1020”, “Fujicure FXR-1030”, “Fujicure FXR-1081”, and “Fujicure FXR-1121” manufactured by T&K TOKA Corporation.

[0048] In order to minimize the amount of unreacted epoxy resin and curing agent, the compounding ratio of the epoxy resin and curing agent contained in the epoxy resin composition is preferably set so that the ratio of the number of functional groups of the curing agent (active hydrogen in the case of an amine curing agent) to the number of epoxy groups of the epoxy resin (number of functional groups of the curing agent / number of epoxy groups of the epoxy resin) is within the range of 0.5 to 2.0, more preferably within the range of 0.6 to 1.3, and even more preferably within the range of 0.8 to 1.2.

[0049] [Inorganic filler] The epoxy resin composition may contain an inorganic filler. By containing an inorganic filler, it is possible to reduce the thermal expansion coefficient and improve the thermal conductivity of a cured product of the epoxy resin composition.

[0050] Specific examples of the inorganic filler include silica, alumina, calcium carbonate, zirconium silicate, calcium silicate, silicon nitride, aluminum nitride, boron nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite, titania, talc, clay, and mica.

[0051] Among the above inorganic fillers, silica is preferred from the viewpoint of reducing the thermal expansion coefficient, and alumina is preferred from the viewpoint of improving thermal conductivity. The inorganic fillers may be used alone or in combination of two or more kinds.

[0052] The content of the inorganic filler contained in the epoxy resin composition is not particularly limited. From the viewpoint of reducing the thermal expansion coefficient and improving the thermal conductivity of the cured product, the content of the inorganic filler is preferably 40 mass% or more of the entire epoxy resin composition, more preferably 50 mass% or more, and even more preferably 60 mass% or more. From the viewpoint of suppressing the increase in viscosity of the epoxy resin composition, the content of the inorganic filler is preferably 90 mass% or less of the entire edge bond material, more preferably 80 mass% or less, and even more preferably 75 mass% or less.

[0053] When the inorganic filler is particulate, its average particle size is not particularly limited. For example, the volume average particle size is preferably 0.05 μm to 20 μm, and more preferably 0.1 μm to 15 μm. When the volume average particle size is 0.05 μm or more, the increase in viscosity of the edge bond material tends to be more suppressed. When the volume average particle size is 20 μm or less, the applicability to narrow gaps tends to be more improved.

[0054] The volume average particle size of the inorganic filler is defined as the particle size (D50) when the cumulative volume from the small diameter side in the volume-based particle size distribution obtained by a laser scattering diffraction particle size distribution measuring device is 50%.

[0055] [Various additives] The epoxy resin composition may contain various additives such as a thixotropic agent, a curing accelerator, a stress relaxation agent, a coupling agent, a colorant, and the like, in addition to the above-mentioned components. When the epoxy resin composition contains components other than the epoxy resin, the curing agent, and the inorganic filler, the total content thereof is preferably 10 mass % or less, and more preferably 5 mass % or less, of the entire epoxy resin composition.

[0056] <Method of manufacturing the structure> The method for producing a structure of the present disclosure includes the steps of placing a curable resin composition on the periphery of a space between a first member and a second member, and curing the curable resin composition.

[0057] The details and preferred aspects of the first member, the second member, and the curable resin composition used in the above method are the same as the details and preferred aspects of the first member, the second member, and the curable resin composition in the above-mentioned structure.

[0058] The method of disposing the curable resin composition on the periphery of the space between the first member and the second member is not particularly limited. For example, it can be performed by a known method using a dispenser, a screen printer, an inkjet printer, etc. In addition, the curable resin composition may be disposed on the first member and then the second resin may be disposed on the first member, or the curable resin composition may be disposed on the first member and then the second resin may be disposed on the first member. EXAMPLES

[0059] The present disclosure will be specifically described below using examples, but the scope of the present disclosure is not limited to these examples.

[0060] (Preparation of Epoxy Resin Composition) An epoxy resin composition was prepared by mixing the components shown in Table 1 in the amounts (parts by mass) shown in Table 1. Details of each component are as follows. The mixing ratio of the epoxy resin and the curing agent was set so that the number of epoxy groups in the epoxy resin was equal to the number of active hydrogens in the curing agent.

[0061] Epoxy resin 1: Bisphenol F type epoxy resin that is liquid at 25℃ Epoxy resin 2: Triglycidyl-p-aminophenol, liquid at 25°C

[0062] Hardener 1: Aliphatic amine that is solid at 25°C Hardener 2: Diethyltoluenediamine, liquid at 25℃ Hardener 3: 3,3'-diethyl-4,4'-diaminodiphenylmethane, liquid at 25°C

[0063] Thixotropic agent: Aerosil silica with a primary particle size of 10 nm to 20 nm, product name "AEROSIL R-202", Nippon Aerosil Co., Ltd. Inorganic filler: Spherical silica with a volume average particle size of 30 μm, product name "Exelica SE-30", Tokuyama Corporation Colorant: Carbon black, product name "MA-100", Mitsubishi Chemical Corporation

[0064] [Table 1]

[0065] (Viscosity measurement) The viscosity of the epoxy resin composition was measured at 10 rpm (revolutions per minute) using a dynamic viscoelasticity measuring device (AR-2000, manufactured by TA Instruments) under a specified temperature condition.

[0066] (Measurement of thixotropic index) The viscosity of the epoxy resin composition at 2.5 rpm (revolutions per minute) and at 10 rpm (revolutions per minute) was measured using a dynamic viscoelasticity measuring device (AR-2000, manufactured by TA Instruments) under specified temperature conditions. The thixotropic index was calculated by dividing the viscosity measurement at 2.5 rpm (revolutions per minute) by the viscosity measurement at 10 rpm (revolutions per minute).

[0067] (Preparation of evaluation structure) A silicon substrate and a semiconductor chip (10 mm×10 mm, thickness 400 μm) were prepared. An epoxy resin composition (25°C) was applied at 25°C using a dispenser (needle diameter 0.82 mm) to a portion corresponding to the outer periphery of a semiconductor chip (gap: 150 μm) placed on a silicon substrate. In this state, a heat treatment was performed at 120°C for 15 minutes to harden the epoxy resin composition.

[0068] The structures produced using the epoxy resin compositions prepared in Examples 1 to 3 were cut, and the cross sections were observed under an electron microscope, revealing that the cured product of the epoxy resin composition was disposed on the periphery of the space between the silicon substrate and the semiconductor chip. The shape of the cured product was almost the same as immediately after it was applied using a dispenser. The epoxy resin composition prepared in Comparative Example 1 spread in the surface direction of the silicon substrate immediately after it was applied onto the silicon substrate using a dispenser, and was unable to maintain its shape. [Explanation of symbols]

[0069] 1...Support 2. Semiconductor element 3...Insulating material

Claims

1. A structure comprising a first member, a second member, and an insulating member disposed on a periphery of a space between the first member and the second member.

2. The structure according to claim 1 , wherein the insulating member is a cured product of a curable resin composition.

3. The structure of claim 2 , wherein the curable resin composition comprises an epoxy resin.

4. The structure according to any one of claims 1 to 3, wherein the first member is a support and the second member is a semiconductor element.

5. The method for manufacturing the structure according to any one of claims 1 to 4, comprising the steps of: disposing a curable resin composition on a peripheral portion of a space between a first member and a second member; and curing the curable resin composition.

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