Method for evaluating the adhesiveness of a resin composition for sealing materials, method for manufacturing a resin composition for sealing materials, and method for manufacturing a semiconductor package

Abstract

To quantitatively measure the adhesive properties of sealing materials formed by compression molding. [Solution] The adhesive strength between the columnar body and the adherend is measured in a test piece comprising an adherend and a columnar body containing a resin composition for sealing material formed on the surface of the adherend by compression molding, and the adhesiveness of the sealing material formed with the tested resin composition for sealing material is evaluated based on the adhesive strength between the columnar body and the adherend.

Description

Technical Field

[0001] The present invention relates to a method for evaluating the adhesiveness of a resin composition for a sealing material, a method for producing a resin composition for a sealing material, and a method for producing a semiconductor package.

Background Art

[0002] In a semiconductor package, a sealing material is filled around a semiconductor element and cured to protect it from light, heat, moisture, dust, etc. As a method of filling and curing a sealing material around a semiconductor element, instead of using a liquid resin composition for a semiconductor sealing material, there is a method of compression molding using a particulate resin composition for a semiconductor sealing material. The sealing material is required to have excellent adhesiveness to a substrate, a resist film, etc.

[0003] However, a method for evaluating the adhesiveness of a sealing material, particularly a method for quantitatively evaluating the adhesiveness of a sealing material formed by compression molding, has not been established. For example, a test piece including a resist layer formed on the surface of a substrate on a flat plate and a sealing material layer formed on the resist layer was prepared, and the adhesiveness of the sealing material was evaluated from the area of the resist layer peeled off together with the sealing material layer when the sealing material layer was peeled off. Also, a test piece in which a columnar body containing a resin composition for a sealing material was formed on the surface of the adherend by transfer molding was prepared, and a shearing force was applied to the columnar body by a shear jig to measure the adhesive strength between the columnar body and the adherend. Further, Patent Document 1 discloses a method for evaluating the adhesiveness between a copper plate and a solid sealing material, in which an ultrasonic flaw detection image of the bonding state of the interface between the copper plate and the solid sealing material is obtained to evaluate peeling.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the above-described method has the problem that it is not possible to quantitatively evaluate the adhesiveness of the encapsulant formed by compression molding. Therefore, in view of this situation, the present disclosure aims to provide a method for evaluating the adhesiveness of a resin composition for encapsulants that can quantitatively evaluate the adhesiveness of a encapsulant formed by compression molding, a method for manufacturing a resin composition for encapsulants, and a method for manufacturing a semiconductor package. [Means for solving the problem]

[0006] Having achieved the objectives described above, this disclosure includes the following: <1> A method for evaluating the adhesiveness of a resin composition for sealing materials, comprising measuring the adhesive strength between a columnar body containing a resin composition for sealing materials formed on the surface of the adherend by compression molding in a test piece, and evaluating the adhesiveness of a sealing material formed from the tested resin composition for sealing materials based on the adhesive strength between the columnar body and the adherend. <2> The test specimen has a plurality of columnar bodies formed on the surface of the adherend. <1> A method for evaluating the adhesion of the resin composition for sealing materials described above. <3> The adhesive strength between the columnar body and the adherend is measured by a shear test in which a shear force is applied to the columnar body using a shear jig. <1> or <2> A method for evaluating the adhesion of the resin composition for sealing materials described above. <4> The adhesion of the sealing material is evaluated based on the adhesion strength measured for the columnar bodies other than those arranged at the periphery of the test piece, out of the adhesion strength measured for the plurality of columnar bodies with respect to the adherend. <2> A method for evaluating the adhesion of the resin composition for sealing materials described above. <5> The adherend includes a resist material, and the adhesion between the sealing material and the resist film formed from the resist material is evaluated. <1> ~ <4> A method for evaluating the adhesion of a resin composition for sealing materials as described in any one of the following. <6> <1> ~ <5> A method for producing a resin composition for sealing materials, comprising evaluating the adhesion between a sealing material formed from a tested resin composition and an adherend using the adhesion evaluation method for a resin composition for sealing materials described in any one of the above, and modifying the tested resin composition for sealing materials based on the evaluation results. <7> The modification of the resin composition for the sealing material involves changing at least one selected from the group consisting of inorganic filler particle size, inorganic filler content, thermosetting resin, and thermosetting resin amount. <6> A method for producing the resin composition for sealing materials described above. <8> The adhesive properties of the modified resin composition for sealing material are evaluated again using the adhesive evaluation method for the resin composition for sealing material. <6> or <7> A method for producing the resin composition for sealing materials described above. <9> <1> ~ <5> A resin composition for sealing materials evaluated by the adhesion evaluation method for a resin composition for sealing materials described in any one of the following, or <6> ~ <8> A method for manufacturing a semiconductor package, comprising sealing a semiconductor element by compression molding using a resin composition for sealing materials manufactured by a method for manufacturing a resin composition for sealing materials described in any one of the above. [Effects of the Invention]

[0007] According to the adhesiveness evaluation method for encapsulating resin compositions of this disclosure, the adhesiveness of an encapsulating material can be quantitatively evaluated based on the adhesive strength between the encapsulating material formed by compression molding using the encapsulating resin composition and the adherend. Furthermore, according to the manufacturing method for encapsulating resin compositions of this disclosure, an encapsulating resin composition capable of forming an encapsulating material with excellent adhesive properties can be manufactured by compression molding. Moreover, according to the manufacturing method for semiconductor packages of this disclosure, a semiconductor package equipped with an encapsulating material formed by compression molding and possessing excellent adhesive properties can be manufactured. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view showing one aspect of a test specimen relating to this disclosure. [Figure 2] This is a plan view showing another aspect of the test specimen relating to this disclosure. [Figure 3]This is a schematic cross-sectional view showing a shear test apparatus on which a test specimen is placed. [Figure 4] This is a characteristic diagram showing the results of measuring the adhesive strength of columnar bodies for test specimen 1. [Figure 5] This is a characteristic diagram showing the results of measuring the adhesive strength of columnar bodies for test specimen 2. [Figure 6] This is a characteristic diagram showing the average adhesive strength of columnar bodies for test specimen 1 and test specimen 2. [Figure 7] This is a characteristic diagram showing the average adhesive strength of columnar bodies for test specimens 3 and 4. [Modes for carrying out the invention]

[0009] The embodiments are described in detail below. However, this disclosure is not limited to the embodiments described below. In the embodiments described below, the components (including elemental steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit this disclosure.

[0010] In this disclosure, the term "process" includes not only processes that are independent of other processes, but also processes that cannot be clearly distinguished from other processes, provided that the purpose of such process is achieved. In this disclosure, the numerical range indicated using "~" includes the numbers before and after "~" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in the numerical ranges described, the upper or lower limit of that range may be replaced with the values ​​shown in the examples. In this disclosure, each component may contain multiple types of the corresponding substance. If multiple types of the substance 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 types of substances present in the composition, unless otherwise specified.

[0011] The method for evaluating the adhesiveness of the resin composition for a sealing material of the present disclosure is a method for measuring the adhesive strength between a columnar body including the resin composition for a sealing material formed on the surface of the adherend by compression molding and the adherend, and evaluating the adhesiveness of the sealing material formed of the tested resin composition for a sealing material based on the adhesive strength between the columnar body and the adherend. According to the method for evaluating the adhesiveness of the resin composition for a sealing material of the present disclosure, in a semiconductor package, the adhesiveness between the sealing material formed by compression molding and the member in contact with the sealing material can be quantitatively evaluated.

[0012] One aspect of the test piece used in the method for evaluating the adhesiveness of the resin composition for a sealing material of the present disclosure is shown in FIG. 1. The test piece 1 shown in FIG. 1 includes a plate-shaped adherend 2 and a columnar body 3 formed on the surface of the adherend 2 by compression molding. The columnar body 3 is formed by compression molding using the resin composition for a sealing material to be evaluated.

[0013] Here, the adherend is formed of the material of the member in contact with the sealing material in a semiconductor package in which a semiconductor element or the like is sealed with a sealing material. Therefore, the adhesiveness between the sealing material formed by compression molding and the adherend is equivalent to the adhesiveness between the sealing material and the member in contact with the sealing material in the semiconductor package. For example, in a semiconductor package, when the sealing material is in contact with a resist film, the adherend is formed of the material of the resist film. Thus, according to the method for evaluating the adhesiveness of the resin composition for a sealing material of the present disclosure, the adhesiveness between the sealing material and the resist film in the semiconductor package can be quantitatively evaluated based on the adhesive strength between the sealing material and the adherend.

[0014] Therefore, the material of the adherend in the method for evaluating the adhesiveness of the resin composition for a sealing material of the present disclosure is not particularly limited, and examples thereof include resist materials, resin materials, metals, glasses, silicon wafers, organic substrates, etc. constituting the semiconductor package. Further, the adherend may be formed by film-forming or laminating the above-mentioned various materials on a substrate. In the test piece, the adherend only needs to be formed on at least a part in contact with the columnar body.

[0015] In addition, in the test piece 1 shown in FIG. 1, the columnar body 3 has a frustum of a cone shape. However, the shape of the columnar body is not limited to a frustum of a cone, and different shapes may be used as long as they are applicable to the test for measuring the adhesive strength described later. As the columnar body, a frustum of a pyramid such as a frustum of a triangular pyramid or a frustum of a quadrangular pyramid may be used, a pyramid such as a cone, a triangular pyramid, or a quadrangular pyramid may be used, or a prism such as a cylinder, a triangular prism, or a quadrangular prism may be used. In the present disclosure, all of these are referred to as columnar bodies.

[0016] Further, FIG. 2 shows another aspect of the test piece used in the method for evaluating the adhesiveness of the resin composition for a sealing material of the present disclosure. The test piece 10 shown in FIG. 2 has a plurality of columnar bodies 12 formed on the surface of the adherend 11. In the example of the test piece 10 shown in FIG. 2, a total of 48 columnar bodies 12 are arranged in 4 columns and 12 rows. The example of the test piece 10 shown in FIG. 2 shows that it may have a plurality of columnar bodies 12, and the number of columnar bodies 12 may be less than or more than 48. In the test piece 10 shown in FIG. 2, the adhesive strength between each of the plurality of columnar bodies 12 and the adherend 11 can be measured by a test for measuring the adhesive strength described later.

[0017] On the other hand, in the method for evaluating the adhesiveness of the resin composition for a sealing material of the present disclosure, the test for measuring the adhesive strength is not particularly limited, and so-called shear tests, pull tests, etc. can be appropriately used. Particularly, as the test for measuring the adhesive strength in the present disclosure, it is preferable that the test is a test for measuring the adhesive strength between the columnar body and the adherend by a shear test in which a shearing force is applied to the columnar body by a shear jig.

[0018] Figure 3 shows one embodiment of a test apparatus for performing a shear test. The shear test apparatus 20 shown in Figure 3 is exemplified as a device for measuring the test piece 1 shown in Figure 1. The shear test apparatus 20 comprises a mounting table 21 on which the test piece 1 is placed, a restricting jig 22 that contacts one end of the test piece 1 placed on the mounting table 21 and restricts the movement of the test piece 1, and a shear jig 23 that applies a shear force to the columnar body 3 of the test piece 1. Although not shown, the shear test apparatus 20 also has a drive device that drives the shear jig 23 in the direction of arrow A in Figure 3 and a sensor that measures the load on the shear jig 23. In addition, the mounting table 21 in the shear test apparatus 20 may be equipped with an XY stage that can be freely driven within the plane on which the test piece 1 is placed.

[0019] In the shear testing apparatus 20 configured as described above, an adhesive strength test can be performed on a test piece 1 placed on a mounting table 21. First, the test piece 1 is placed on the mounting table 21, and the tip of the shear jig 23 is positioned at a predetermined distance (D in Figure 3) from the mounting table 21. Then, the shear testing apparatus 20 drives the shear jig 23 in the direction A in Figure 3, thereby applying a shear force to the columnar body 3, and the load at which the columnar body 3 detaches from the adherend 2 is measured. By this method, the adhesive strength between the columnar body 3 and the adherend 2 can be measured.

[0020] Similarly, with respect to the test specimen 10 shown in Figure 2, the adhesive strength between each of the multiple columnar bodies 12 and the adherend 11 can be measured using the shear test apparatus 20. In this case, since the adhesive strength with the adherend 11 is measured for each arrangement of the multiple columnar bodies 12 placed on the test specimen 10, it is also possible to determine the distribution of adhesive strength corresponding to the positions of the multiple columnar bodies 12.

[0021] In the adhesiveness evaluation method for resin compositions for encapsulants of this disclosure, when using a test specimen having multiple columnar bodies as shown in Figure 2, it is preferable to evaluate the adhesiveness of the encapsulant based on the adhesive strength measured for the columnar bodies other than those located at the periphery of the test specimen, out of the adhesive strength measured for the multiple columnar bodies with respect to the adherend. In the example of test specimen 10 shown in Figure 2, the columnar bodies located at the periphery of the test specimen refer to the 8 columnar bodies 12 in the 1st and 12th columns, or the 24 columnar bodies 12 in the 1st and 4th rows, etc., out of a total of 48 columnar bodies 12 in 4 rows and 12 columns. This is because the columnar bodies located at the periphery of the test specimen may already be subjected to stress during the manufacturing process of the test specimen, and it may not be possible to accurately measure the adhesive strength between the columnar bodies and the adherend. Thus, by basing the evaluation on the adhesive strength measured for the columnar bodies other than those located at the periphery of the test specimen, out of the adhesive strength measured for the multiple columnar bodies with respect to the adherend, the adhesiveness of the encapsulant can be evaluated more accurately. In the method for evaluating the adhesiveness of the resin composition for sealing materials of this disclosure, the measurement of adhesive strength may be performed on all columnar bodies other than those arranged at the periphery, or on only some of them.

[0022] As described above, the adhesiveness evaluation method for encapsulating resin compositions of this disclosure quantitatively evaluates the adhesiveness of encapsulating material formed from the tested encapsulating resin composition by measuring the adhesive strength between the columnar body and the adherend in the test piece. In particular, the adhesiveness evaluation method for encapsulating resin compositions of this disclosure allows for highly accurate evaluation of the adhesiveness of encapsulating material formed by compression molding in actual semiconductor packages by forming a columnar body by compression molding of the encapsulating resin composition.

[0023] [Method for producing particulate resin composition for encapsulating materials] The method for manufacturing a resin composition for sealing materials according to this disclosure is a method for quantitatively evaluating the adhesion of a sealing material formed from a tested resin composition for sealing materials using the adhesion evaluation method for resin compositions for sealing materials according to this disclosure described above, and modifying the tested resin composition for sealing materials based on the evaluation results. Evaluating adhesion means including quantitatively evaluating the adhesive strength of the sealing material formed from the tested resin composition for sealing materials to the member in contact with it. According to the method for manufacturing a resin composition for sealing materials according to this disclosure, a resin composition for sealing materials that can form a sealing material with excellent adhesion to the contacting portion can be manufactured by modifying the tested resin composition for sealing materials.

[0024] In the method for producing the resin composition for sealing materials of this disclosure, modifying the resin composition for sealing materials includes changing the composition contained in the resin composition for sealing materials, changing the particle size of the resin composition for sealing materials, and so on. The composition of the resin composition for sealing materials will be described in detail later, but it contains a thermosetting resin, a curing agent, and an inorganic filler, and may optionally contain various additives such as curing accelerators, colorants, coupling agents, ion exchangers, mold release agents, flame retardants, and stress relaxants. In addition to these additives, the resin composition for sealing materials may optionally contain various additives such as ultraviolet absorbers that are well known in the art.

[0025] Examples of modifying the composition of a resin composition for sealing materials include changing at least one selected from the group consisting of inorganic filler particle size, inorganic filler content, thermosetting resin, and thermosetting resin amount. Other examples of modifying the composition of a resin composition for sealing materials include changing the type of additive such as silicones and the amount of such additives.

[0026] Furthermore, in the method for manufacturing a resin composition for sealing materials of this disclosure, it is preferable to modify the resin composition for sealing materials as described above, and then re-evaluate the adhesion of the modified resin composition for sealing materials using the adhesion evaluation method for resin compositions for sealing materials of this disclosure. This allows confirmation that the adhesion of the modified resin composition for sealing materials formed by compression molding has improved. In addition, in the method for manufacturing a resin composition for sealing materials of this disclosure, the modification of the resin composition for sealing materials and the subsequent re-evaluation can be repeated multiple times. By repeating the modification of the resin composition for sealing materials and the subsequent re-evaluation multiple times, the adhesion of the resin composition for sealing materials formed by compression molding can be made even better.

[0027] As described above, the method for manufacturing a resin composition for encapsulating materials according to the present disclosure makes it possible to manufacture a resin composition for encapsulating materials that exhibits excellent adhesion when formed by compression molding. For example, by applying the method for manufacturing a resin composition for encapsulating materials according to the present disclosure and modifying a resin composition for encapsulating materials that had insufficient adhesion when formed by compression molding, it is possible to manufacture a resin composition for semiconductor encapsulating materials that can form an encapsulating material with improved adhesion.

[0028] [Manufacturing method for semiconductor package] The semiconductor package manufacturing method of this disclosure is a semiconductor encapsulant resin composition that can form an encapsulant exhibiting excellent adhesion by compression molding, as determined by the adhesiveness evaluation method for encapsulant resin compositions of this disclosure described above, or a method of encapsulating a semiconductor element by compression molding using an encapsulant resin composition manufactured by the manufacturing method for encapsulant resin compositions of this disclosure described above. According to the semiconductor package manufacturing method of this disclosure, since an encapsulant resin composition that becomes an encapsulant exhibiting excellent adhesion by compression molding can be used, a highly reliable semiconductor package with encapsulant peeling prevented can be manufactured.

[0029] The semiconductor package manufacturing method of the present disclosure may further include steps included in a conventional semiconductor package manufacturing method that applies compression molding. The semiconductor package manufacturing method of the present disclosure may include, for example, a step of arranging a semiconductor element on a support. The semiconductor package manufacturing method of the present disclosure may also include, for example, a step of arranging the support on which the semiconductor element is arranged in a cavity of a mold, and arranging a resin composition for sealing material in the cavity. In the semiconductor package manufacturing method of the present disclosure, a sealing material that seals the semiconductor element arranged on the support can be formed by compression molding using a mold in which the support and a particulate resin composition for semiconductor sealing material are arranged in a cavity.

[0030] The support structure is not particularly limited and can include lead frames, pre-wired tape carriers, wiring boards, glass, silicon wafers, organic substrates, etc. In addition to semiconductor elements, the semiconductor package may also include active elements such as transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, and coils.

[0031] More specifically, semiconductor packages include common resin-encapsulated ICs such as DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead package), TSOP (Thin Small Outline Package), and TQFP (Thin Quad Flat Package); TCP (Tape Carrier Package) which has a structure in which elements connected to a tape carrier with bumps are encapsulated; COB (Chip On Board) modules, hybrid ICs, multi-chip modules, etc. which have a structure in which elements connected to wiring formed on a support member with wire bonding, flip-chip bonding, solder, etc. are encapsulated; and BGA (Ball Grid Array), CSP (Chip Size Package), MCP (Multi Chip Package) which have a structure in which elements are mounted on the surface of a support member with terminals for connecting to a wiring board formed on the back, and the elements are connected to the wiring formed on the support member with bumps or wire bonding, and then the elements are encapsulated. In particular, the semiconductor package manufacturing method of this disclosure is preferably applied to semiconductor packages having a narrow gap structure, due to the increasing integration and miniaturization of semiconductor packages in recent years. Examples of such semiconductor packages include SiP (Single In-line Package) and HBM (High Bandwidth Memory).

[0032] [Resin composition for encapsulant] The following describes the adhesiveness evaluation method for the encapsulating resin composition of this disclosure, the manufacturing method for the encapsulating resin composition of this disclosure, and the encapsulating resin composition applicable to the manufacturing method for the semiconductor package of this disclosure. However, the adhesiveness evaluation method for the encapsulating resin composition of this disclosure, the manufacturing method for the encapsulating resin composition of this disclosure, and the manufacturing method for the semiconductor package of this disclosure are not limited to the encapsulating resin composition.

[0033] The resin composition for sealing materials according to this disclosure is obtained by atomizing a thermosetting resin composition that constitutes a sealing material. The resin composition for sealing materials contains a thermosetting resin, a curing agent, and an inorganic filler, and may optionally contain various additives such as a curing accelerator, a colorant, a coupling agent, an ion exchanger, a mold release agent, a flame retardant, and a stress relaxant. In addition to these additives, the resin composition for sealing materials may optionally contain various additives such as ultraviolet absorbers that are well known in the art.

[0034] (thermosetting resin) The resin composition for sealing materials according to this disclosure contains a thermosetting resin. The type of thermosetting resin is not particularly limited and includes epoxy resins, phenolic resins, thiol resins, urea resins, melamine resins, urethane resins, silicone resins, maleimide resins, unsaturated polyester resins, etc. In this disclosure, resins that exhibit both thermoplastic and thermosetting properties, such as acrylic resins containing epoxy groups, are included in "thermosetting resins." The thermosetting resin may be solid or liquid at room temperature and atmospheric pressure (for example, 25°C and atmospheric pressure), but it is preferable that it be solid. One type of thermosetting resin may be used alone, or two or more types may be used in combination.

[0035] The thermosetting resin preferably contains an epoxy resin. The type of epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. Specifically, novolac-type epoxy resins (phenol novolac-type epoxy resins, orthocresol novolac-type epoxy resins, etc.) are obtained by condensing or co-condensing a novolac resin obtained by condensing or co-condensing a novolac resin obtained by phenol compounds selected from the group consisting of phenol compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene under an acidic catalyst with an aliphatic aldehyde compound such as formaldehyde, acetaldehyde, or propionaldehyde, and then epoxidizing the novolac resin. Copolymer epoxy resins that have been modified; diphenylmethane-type epoxy resins that are diglycidyl ethers of bisphenol A, bisphenol F, etc.; biphenyl-type epoxy resins that are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins that are diglycidyl ethers of stilbene-based phenol compounds; sulfur atom-containing epoxy resins that are diglycidyl ethers of bisphenol S, etc.; epoxy resins that are glycidyl ethers of alcohols such as butanediol, polyethylene glycol, and polypropylene glycol; glycidyl ester-type epoxy resins that are glycidyl esters of polycarboxylic acid compounds such as phthalic acid, isophthalic acid, and tetrahydrophthalic acid; glycidylamine-type epoxy resins in which the active hydrogen bonded to the nitrogen atom of aniline, diaminodiphenylmethane, isocyanuric acid, etc. is replaced with a glycidyl group; dicyclopentadiene-type epoxy resins that are epoxidized from a copolymer resin of dicyclopentadiene and a phenol compound;Alicyclic epoxy resins such as vinylcyclohexene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 2-(3,4-epoxy)cyclohexyl-5,5-spiro(3,4-epoxy)cyclohexane-m-dioxane, which have epoxidized olefin bonds within the molecule; paraxylylene-modified epoxy resins, which are glycidyl ethers of paraxylylene-modified phenol resins; metaxylylene-modified epoxy resins, which are glycidyl ethers of metaxylylene-modified phenol resins; terpene-modified epoxy resins, which are glycidyl ethers of terpene-modified phenol resins; and dicyclopentadiene-modified phenol resins, which are glycidyl ethers of dicyclo Examples of epoxy resins include: pentadiene-modified epoxy resins; cyclopentadiene-modified epoxy resins, which are glycidyl ethers of cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified epoxy resins, which are glycidyl ethers of polycyclic aromatic ring-modified phenolic resins; naphthalene-type epoxy resins, which are glycidyl ethers of naphthalene ring-containing phenolic resins; halogenated phenol novolac-type epoxy resins; hydroquinone-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; and aralkyl-type epoxy resins, which are epoxidized aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins. Furthermore, epoxides of silicone resins and aminophenol-type epoxy resins, which are glycidyl ethers of aminophenols, can also be cited as epoxy resins. These epoxy resins may be used individually or in combination of two or more types.

[0036] Among the epoxy resins mentioned above, epoxy resins selected from the group consisting of biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, sulfur atom-containing epoxy resins, novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, copolymer-type epoxy resins, and aralkyl-type epoxy resins (these are referred to as "specific epoxy resins") from the viewpoint of balancing heat resistance and fluidity. Specific epoxy resins may be used individually or in combination of two or more types.

[0037] (Hardening agent) The resin composition for sealing materials according to this disclosure contains a curing agent. The type of curing agent is not particularly limited, as long as it is a compound that undergoes a curing reaction with the thermosetting resin used in combination. For example, examples of curing agents used in combination with epoxy resins include phenolic curing agents, amine curing agents, acid anhydride curing agents, polymercaptan curing agents, polyaminoamide curing agents, isocyanate curing agents, and blocked isocyanate curing agents. The curing agent may be used alone or in combination of two or more types. The curing agent may be solid or liquid at room temperature and pressure (e.g., 25°C, atmospheric pressure), but it is preferable that it be solid. When the thermosetting resin is an epoxy resin, a phenolic curing agent or an amine curing agent is preferred from the viewpoint of heat resistance.

[0038] Examples of phenolic curing agents include phenolic resins and polyhydric phenolic compounds having two or more phenolic hydroxyl groups in one molecule. Specifically, these include polyhydric phenolic compounds such as resorcinol, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenols; novolac-type phenolic resins obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene with an aldehyde compound such as formaldehyde, acetaldehyde, or propionaldehyde under an acidic catalyst; and phenolic resins synthesized from the above phenolic compounds with dimethoxyp-xylene, bis(methoxymethyl)biphenyl, etc. Examples include aralkyl-type phenolic resins such as ol-aralkyl resins and naphthol-aralkyl resins; para-xylylene and / or meta-xylylene-modified phenolic resins; melamine-modified phenolic resins; terpene-modified phenolic resins; dicyclopentadiene-type phenolic resins and dicyclopentadiene-type naphthol resins synthesized by copolymerization of the above phenolic compounds with dicyclopentadiene; cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified phenolic resins; biphenyl-type phenolic resins; triphenylmethane-type phenolic resins obtained by condensation or co-condensation of the above phenolic compounds with aromatic aldehyde compounds such as benzaldehyde and salicylaldehyde under an acidic catalyst; and phenolic resins obtained by copolymerizing two or more of these. Furthermore, monovalent phenolic compounds having one phenolic hydroxyl group in one molecule can also be used as phenolic curing agents. These phenolic curing agents may be used individually or in combination of two or more types.

[0039] Among phenolic curing agents, at least one selected from the group consisting of aralkyl-type phenolic resins, dicyclopentadiene-type phenolic resins, triphenylmethane-type phenolic resins, copolymerized phenolic resins of triphenylmethane-type phenolic resins and aralkyl-type phenolic resins, and novolac-type phenolic resins (these are referred to as "specific phenolic curing agents") is preferred from the viewpoint of heat resistance. Specific phenolic curing agents may be used individually or in combination of two or more types.

[0040] (Curing accelerator) The resin composition for sealing materials relating to this disclosure may contain a curing accelerator. The type of curing accelerator is not particularly limited and can be selected according to the type of curable resin, the desired properties of the thermosetting resin composition, etc.

[0041] From the viewpoint of curability and fluidity, it is preferable that the curing accelerator contains a phosphonium compound. Specifically, phosphonium compounds include triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkyl·alkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, and tris(tetraalkoxyphenyl)phosphine. It has intramolecular polarization formed by adding π-bonded compounds such as tertiary phosphines (sphing, trialkylphosphines, dialkylarylphosphines, alkyldiarylphosphines) to quinone compounds such as maleic anhydride, 1,4-benzoquinone, 2,5-tholquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, and diazophenylmethane. Compounds that do this; tertiary phosphines and 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, 3-chlorophenol, 2-chlorophenol, 4-iodidephenol, 3-iodidephenol, 2-iodidephenol, 4-bromo-2-methylphenol, 4-bromo-3-methylphenol, 4-bromo-2,6-dimethylphenol, 4-bromo-3,5-dimethylphenol, 4-bromo-2,6-di-tert-butylphenol, 4-chloro-1-naphthol, 1-bromo-2-na Examples include compounds with intramolecular polarization obtained by reacting halogenated phenol compounds such as phthol, 6-bromo-2-naphthol, and 4-bromo-4'-hydroxybiphenyl, followed by a dehalogenation step; salts of tetrasubstituted phosphoniums such as tetraphenylphosphonium and tetrasubstituted borates such as tetra-p-tolylborate; salts of tetrasubstituted phosphoniums with anions obtained by removing a proton from a phenol compound; and salts of tetrasubstituted phosphoniums with anions obtained by removing a proton from a carboxylic acid compound.

[0042] (Inorganic filler) The resin composition for semiconductor encapsulants according to this disclosure contains an inorganic filler. The type of inorganic filler is not particularly limited. Specifically, examples include silica such as spherical silica and crystalline silica, glass, alumina, calcium carbonate, zirconium silicate, calcium silicate, silicon nitride, aluminum nitride, boron nitride, beryllia, zirconia, zircon, fossterite, steatite, spinel, mullite, titania, talc, clay, and mica. Inorganic fillers having flame retardant properties may also be used. Examples of inorganic fillers having flame retardant properties include aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as magnesium-zinc composite hydroxides, and zinc borate. Among these, spherical silica is preferred from the viewpoint of reducing the coefficient of thermal expansion, and alumina is preferred from the viewpoint of high thermal conductivity. One type of inorganic filler may be used alone, or two or more types may be used in combination. Examples of inorganic filler states include powder, beads formed from spherical powder, and fibers.

[0043] The content of inorganic filler in the resin composition for sealing materials is not particularly limited. From the viewpoint of fluidity and strength, it is preferably 30% to 90% by volume of the total resin composition for sealing materials, more preferably 35% to 80% by volume, and even more preferably 40% to 70% by volume. When the inorganic filler content is 30% by volume or more of the resin composition for sealing materials, the properties such as the coefficient of thermal expansion, thermal conductivity, and elastic modulus of the cured product tend to improve further. When the inorganic filler content is 90% by volume or less of the resin composition for sealing materials, the increase in viscosity of the resin composition for sealing materials is suppressed, fluidity improves further, and moldability tends to be better.

[0044] The average particle size of the inorganic filler is not particularly limited. For example, the volume-average particle size is preferably 0.2 μm to 50 μm, and more preferably 0.5 μm to 30 μm. When the volume-average particle size is 0.2 μm or more, the increase in viscosity of the thermosetting resin composition tends to be more suppressed. When the volume-average particle size is 50 μm or less, the ability to fill narrow gaps tends to be more improved. The volume-average particle size of the inorganic filler refers to the value measured as the volume-average particle size (D50) using a laser diffraction scattering particle size distribution analyzer.

[0045] The volume-average particle size of inorganic fillers in cured materials can be measured by known methods. For example, inorganic fillers can be extracted from the cured material using an organic solvent, nitric acid, aqua regia, etc., and thoroughly dispersed using an ultrasonic disperser or the like to prepare a dispersion. Using this dispersion, the volume-average particle size of the inorganic fillers can be measured from the volume-based particle size distribution measured by a laser diffraction scattering particle size distribution analyzer. Alternatively, the volume-average particle size of the inorganic fillers can be measured from the volume-based particle size distribution obtained by embedding the cured material in a transparent epoxy resin or the like, polishing the resulting cross-section, and observing it with a scanning electron microscope. Furthermore, it can also be measured by continuously observing the two-dimensional cross-section of the cured material using a FIB (Focused Ion Beam Scanning Electron Microscope) and performing three-dimensional structural analysis.

[0046] From the viewpoint of the fluidity of the resin composition for sealing materials, the particle shape of the inorganic filler is preferably spherical rather than angular, and the particle size distribution of the inorganic filler is preferably widely distributed.

[0047] (Coupling agent) If the resin composition for sealing materials contains an inorganic filler, a coupling agent may be included to improve the adhesion between the resin component and the inorganic filler. The type of coupling agent is not particularly limited, and known coupling agents can be used. Examples of coupling agents include silane coupling agents and titanium coupling agents. One type of coupling agent may be used alone, or two or more types may be used in combination.

[0048] Examples of silane coupling agents include epoxy-based silane coupling agents such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and glycidoxyoctyltrimethoxysilane; amine-based silane coupling agents such as 3-aminopropyltriethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propyltriethoxysilane, 3-aminopropyltrimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane; mercapto-based silane coupling agents such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropyltriethoxysilane; and 3-ureidopropyltriethoxysilane, octenyltrimethoxysilane, and methacryloxyoctyltrimethoxysilane.

[0049] Examples of titanium coupling agents include isopropyl triisostearoyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl phosphite) titanate, bis(dioctyl pyrophosphate) oxyacetate titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacrylate isostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl isostearoyl diacrylic titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, and tetraisopropyl bis(dioctyl phosphite) titanate.

[0050] When the resin composition for sealing materials contains a coupling agent, the content of the coupling agent is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 8 parts by mass, and even more preferably 0.05 to 5 parts by mass, per 100 parts by mass of the inorganic filler, from the viewpoint of adhesion at the interface between the thermosetting resin and the inorganic filler.

[0051] (Ion exchanger) The resin composition for sealing materials may contain an ion exchanger. In particular, it is preferable to include an ion exchanger from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of electronic components. The ion exchanger is not particularly limited, and conventionally known ones can be used. Specifically, examples include hydrotalcite compounds and hydrated oxides of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, and bismuth. One type of ion exchanger may be used alone, or two or more types may be used in combination.

[0052] If the resin composition for sealing materials contains an ion exchanger, there are no particular restrictions on its content as long as it is sufficient to capture ions such as halogen ions. For example, it is preferably 0.1 to 30 parts by mass, and more preferably 1 to 15 parts by mass, per 100 parts by mass of the resin component.

[0053] (Release agent) The resin composition for sealing materials may contain a release agent to obtain good release properties from the mold during molding. The release agent is not particularly limited, and conventionally known ones can be used. Specifically, examples include carnauba wax, higher fatty acids such as montanic acid and stearic acid, higher fatty acid metal salts, ester waxes such as montanic acid esters, and polyolefin waxes such as polyethylene oxide and non-oxidized polyethylene. One type of release agent may be used alone, or two or more types may be used in combination.

[0054] When the resin composition for sealing materials contains a release agent, the amount is preferably 0.01 to 15 parts by mass, and more preferably 0.1 to 10 parts by mass, per 100 parts by mass of the resin component. When the amount of release agent is 0.01 parts by mass or more per 100 parts by mass of the resin component, sufficient release properties tend to be obtained. When the amount of release agent is 15 parts by mass or less per 100 parts by mass of the resin component, better adhesion tends to be obtained.

[0055] (Flame retardant) The resin composition for sealing materials may contain a flame retardant. The flame retardant is not particularly limited, and conventionally known ones can be used. Specifically, examples include organic or inorganic compounds containing halogen atoms, antimony atoms, nitrogen atoms, or phosphorus atoms, and metal hydroxides. The flame retardant may be used alone or in combination of two or more types.

[0056] If the resin composition for sealing material contains a flame retardant, the amount is not particularly limited as long as it is sufficient to obtain the desired flame retardant effect. For example, it is preferably 1 to 300 parts by mass, and more preferably 2 to 150 parts by mass, per 100 parts by mass of the resin component.

[0057] (Coloring agent) The resin composition for sealing materials may further contain a coloring agent. Examples of known coloring agents include carbon black, organic dyes, organic pigments, titanium dioxide, red lead, and red iron oxide. The amount of coloring agent can be appropriately selected depending on the purpose. One type of coloring agent may be used alone, or two or more types may be used in combination.

[0058] (Stress reliever) The resin composition for sealing materials may contain stress-relieving agents such as silicone oil and silicone rubber particles. Including stress-relieving agents can further reduce warping deformation and the occurrence of package cracks in semiconductor packages. Examples of stress-relieving agents include commonly used and known stress-relieving agents (flexible agents). Specifically, these include thermoplastic elastomers such as silicone-based, styrene-based, olefin-based, urethane-based, polyester-based, polyether-based, polyamide-based, and polybutadiene-based; rubber particles such as NR (natural rubber), NBR (acrylonitrile-butadiene rubber), acrylic rubber, urethane rubber, and silicone powder; methyl methacrylate-styrene-butadiene copolymer (MBS), methyl methacrylate-silicone copolymer, methyl methacrylate-butyl acrylate copolymer, indene-containing copolymers of indenes such as indene and alkylindene and styrenes such as styrene and alkylstyrene and phenols, with aromatic olefins such as coumarone as other constituent monomers; and epoxy-modified silicone resins. One type of stress-relieving agent may be used alone, or two or more types may be used in combination.

[0059] When the resin composition for sealing materials contains a stress-relieving agent, the amount of stress-relieving agent is preferably 1 to 50 parts by mass per 100 parts by mass of the resin component.

[0060] (Method for preparing resin compositions for sealing materials) The method for preparing the resin composition for sealing materials is not particularly limited. A common method involves thoroughly mixing predetermined amounts of components using a mixer or the like, then melt-kneading them using a mixing roll, extruder, or the like, followed by cooling and pulverization. More specifically, for example, a method involves uniformly stirring and mixing predetermined amounts of the above-mentioned components, then kneading them using a kneader, roll, extruder, or the like that has been preheated to 70°C to 140°C, followed by cooling and pulverization.

[0061] The resin composition for sealing is preferably solid at room temperature and atmospheric pressure (for example, 25°C and atmospheric pressure). Here, "particulate" is not particularly limited and includes powder, granules, tablets, pellets, granules, etc. When the resin composition for sealing is in tablet or pellet form, it is preferable from the viewpoint of handling that its dimensions and mass are such that they are suitable for the molding conditions of the package. [Examples]

[0062] The embodiments of this disclosure will be described in detail below with reference to examples, but the technical scope of this disclosure is not limited to these examples.

[0063] [Preparation of test specimens] In this example, two test specimens were prepared: Test specimen 1, which has an adherend containing a liquid resist material, and Test specimen 2, which has an adherend containing a resist film. Test specimens 1 and 2 were prepared similarly except for the difference in the adherend material. In Test specimens 1 and 2, the columnar bodies were formed by compression molding of a resin composition for sealing materials containing epoxy resin, a curing agent, a curing accelerator, a coupling agent, a release agent, a pigment, and an inorganic filler. As shown in Figure 2, Test specimens 1 and 2 have a total of 48 columnar bodies in 4 columns and 12 rows.

[0064] Test specimen 1 has a surface forming a columnar body coated with a liquid resist material, and the layer formed by the liquid resist material is used as the substrate. In this example, SR1 manufactured by Taiyo Ink Manufacturing Co., Ltd. was used as the liquid resist material. Test specimen 2 has a resist film attached to the surface forming a columnar body, and the resist film is used as the substrate. In this example, AUS308 manufactured by Taiyo Ink Manufacturing Co., Ltd. was used as the resist film.

[0065] Furthermore, for the compression molding that forms a columnar body on the adherend, the molding temperature was set to 175°C, the molding pressure to 20 tons, the molding time to 13 to 14 seconds, and the curing time to 120 seconds. Test specimens 1 and 2 were prepared in the manner described above.

[0066] [Adhesion strength test] The adhesive strength of columnar bodies to the adherend was measured using a shear test with ROYCE650 (Hugl Electronics) on test specimens 1 and 2. The measurement conditions were as follows: The tool lift height (D in the apparatus shown in Figure 3) of the ROYCE650 used in this example was set to 100 μm, and the axis speed (movement speed in the direction of arrow A in Figure 3) was set to 50 μm / s.

[0067] Figure 4 shows the results of measuring the adhesive strength of test piece 1, which uses liquid crystal resist, and Figure 5 shows the results of measuring the adhesive strength of test piece 2, which uses resist film. Figures 4 and 5 show the results of shear tests on a total of 48 columnar bodies, 4 rows and 12 columns in total. In Figures 4 and 5, the 4 rows and 12 columns of columnar bodies in test pieces 1 and 2 are conveniently labeled as rows A to D and columns 1 to 12. Table 1 shows the average values ​​of rows A to D calculated from the results shown in Figures 4 and 5.

[0068] [Table 1]

[0069] Furthermore, the average adhesive strength for all columnar bodies in test specimen 1 was 10.45, with (overall average - minimum) being 2.94 and (maximum - overall average) being 5.51. For all columnar bodies in test specimen 2, the average adhesive strength was 5.14, with (overall average - minimum) being 5.14 and (maximum - overall average) being 3.28. These results clearly show that the adhesive strength between the columnar bodies and the adherend (liquid resist) in test specimen 1 is superior to the adhesive strength between the columnar bodies and the adherend (resist film) in test specimen 2 (Figure 6).

[0070] Furthermore, as a comparative example, test specimens 3 and 4 were prepared by transfer molding, unlike test specimens 1 and 2 described above. Test specimen 3 had a liquid crystal resist as the substrate, similar to test specimen 1, and test specimen 4 had a resist film as the substrate, similar to test specimen 2. Shear tests were performed on test specimens 3 and 4 in the same manner, and the average adhesive strength was calculated for all columnar bodies. The results are shown in Figure 7. As can be seen from Figure 7, no difference in adhesive strength was observed between test specimens 3 and 4.

[0071] The results from test specimens 1 and 2, and test specimens 3 and 4, revealed that the adhesion between a sealing material formed by compression molding and the member in contact with it cannot be evaluated using test specimens formed by transfer molding. In contrast, it was found that by using test specimens 1 and 2, which are columnar bodies formed by compression molding, the adhesion between a sealing material formed by compression molding and the member in contact with it can be quantitatively evaluated. [Explanation of Symbols]

[0072] 1…Test specimen, 2…Adhesion substrate, 3…Columnar body, 10…Test specimen, 11…Adhesion substrate, 12…Columnar body, 20…Shear test apparatus, 21…Mounting platform, 22…Restraining jig, 23…Shear jig

Claims

1. The adhesive strength between the columnar body and the adherend is measured in a test piece comprising an adherend and a columnar body containing a sealing resin composition formed on the surface of the adherend by compression molding. A method for evaluating the adhesiveness of a resin composition for sealing materials, comprising evaluating the adhesiveness of a sealing material formed from the tested resin composition for sealing materials based on the adhesive strength between the columnar body and the adherend.

2. The method for evaluating the adhesion of a resin composition for sealing material according to claim 1, wherein the test piece has a plurality of columnar bodies formed on the surface of the adherend.

3. A method for evaluating the adhesiveness of a resin composition for sealing materials according to claim 1, wherein the adhesive strength between the columnar body and the adherend is measured by a shear test in which a shear force is applied to the columnar body using a shear jig.

4. A method for evaluating the adhesion of a resin composition for a sealing material according to claim 2, wherein the adhesion of the sealing material is evaluated based on the adhesion strength measured for the columnar bodies other than the columnar bodies arranged at the periphery of the test piece, among the adhesion strength measured for the plurality of columnar bodies with respect to the adherend.

5. The method for evaluating the adhesion of a resin composition for a sealing material according to claim 1, wherein the adherend includes a resist material, and the adhesion between the sealing material and a resist film formed from the resist material is evaluated.

6. The adhesion between the encapsulant formed from the tested encapsulant resin composition and the adherend is evaluated by the adhesion evaluation method for encapsulant resin compositions described in any one of claims 1 to 5. A method for producing a resin composition for sealing materials, comprising modifying the tested resin composition for sealing materials based on evaluation results.

7. The method for producing the resin composition for sealing material according to claim 6, wherein the modification of the resin composition for sealing material involves changing at least one selected from the group consisting of inorganic filler particle size, inorganic filler content, thermosetting resin, and thermosetting resin amount.

8. A method for producing a resin composition for sealing materials according to claim 6, wherein the adhesiveness of the modified resin composition for sealing materials is evaluated again using the adhesiveness evaluation method for resin compositions for sealing materials.

9. A method for manufacturing a semiconductor package, comprising sealing a semiconductor element by compression molding using a resin composition for sealing material that has been evaluated by the adhesion evaluation method for a resin composition for sealing material described in any one of claims 1 to 5, or a resin composition for sealing material manufactured by the method for manufacturing a resin composition for sealing material described in any one of claims 6 to 8.

Images