JP2017011254A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive film and a resin composition capable of realizing connection by a connecting metal with high reliability by improving heat resistance, a connection method of a circuit member in which a highly reliable connection by the connecting metal is realized, and a semiconductor device having a highly reliable connection structure.SOLUTION: A resin composition which has a flux function and is interposed between a mounting substrate 1 (first circuit member) equipped with an upper surface 152 (first surface) and a terminal 14 (first terminal) and a semiconductor element 2 (second circuit member) equipped with a lower surface 251 (second surface) and a terminal 242 (second terminal), and while a bump electrode 3 (connecting metal) provided at the terminal 242 is heated to a temperature which is lower than a melting point of the bump electrode 3, the terminal 14 and the terminal 242 are pressed against each other for jointing through the bump electrode 3. It contains a compound having a flux function and a tris (hydroxyphenyl) methane type epoxy resin.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a resin composition, an adhesive film, a circuit member connection method, and a semiconductor device.

  In recent years, miniaturization, weight reduction, and high performance of electronic devices have been demanded, and in multilayer printed wiring boards, miniaturization and high density of wiring are progressing. Along with this, there is an increasing demand for thinning and miniaturization of a structure for mounting a semiconductor chip on a mounting substrate.

  Therefore, as a method of mounting the semiconductor chip on the mounting substrate, a large number of bump electrodes are formed on the surface of the semiconductor chip electrode, and the chip-side electrode and the substrate-side electrode are electrically connected via the bump electrode. Flip chip mounting to connect to is popular. According to such flip-chip mounting, it is possible to easily realize a multi-pin and downsized connection structure.

  Patent Document 1 discloses manufacturing a semiconductor device by connecting a semiconductor chip to a mounting substrate via bump electrodes (solder bumps).

JP 2001-332583 A

  The object of the present invention is to improve the heat resistance, thereby realizing a resin composition and an adhesive film that can realize connection with a connection metal with high reliability, and highly reliable connection with a connection metal. Another object of the present invention is to provide a method for connecting circuit members and a semiconductor device having a highly reliable connection structure.

Such an object is achieved by the present inventions (1) to (7) below.
(1) a first circuit member comprising a first surface and a first terminal provided on the first surface side;
Interposing between a second circuit member comprising a second surface and a second terminal provided on the second surface side,
While heating the connection metal provided on at least one of the first terminal and the second terminal to a first temperature lower than the melting point of the connection metal, the first circuit member and the second circuit member A resin composition having a flux function, which is used when the first terminal and the second terminal are joined to each other via the connection metal,
A resin composition comprising a compound having a flux function and an epoxy resin, wherein the epoxy resin contains a tris (hydroxyphenyl) methane type epoxy resin.

  (2) The resin composition according to (1), wherein the compound having the flux function expresses the flux function at 220 ° C. or lower.

  (3) An adhesive film formed using the resin composition according to (1) or (2).

(4) a first circuit member comprising a first surface and a first terminal provided on the first surface side;
A second circuit member comprising: a second surface; and a second terminal provided on the second surface side;
A connecting metal provided on at least one of the first terminal and the second terminal;
Provided between the first surface and the second surface, the resin composition according to the above (1) or (2) or the adhesive film according to the above (3);
A preparation process to prepare,
While heating the connection metal to a first temperature lower than its melting point, pressing the first terminal and the second terminal through the connection metal and the resin composition or the adhesive film, A method for connecting circuit members, comprising: a joining step of joining the first terminal and the second terminal via the connection metal.

  (5) After the joining step, an alloy promoting step for further promoting alloying of the first terminal of the first circuit member, the second terminal of the second circuit member, and the joining metal. The circuit member connection method according to (4) above.

  (6) In the joining step, the heating temperature for heating the connection metal is (4) or (5), which is lower by 20 ° C. or more and 45 ° C. or less than the melting point of the solder component contained in the connection metal. The connection method of the circuit member as described in 2.

(7) a first circuit member, which is a semiconductor component, comprising a first surface and a first terminal provided on the first surface side;
A second circuit member comprising: a second surface; and a second terminal provided on the second surface side;
The resin composition according to (1) or (2) or the adhesive film according to (6),
While heating the connection metal provided on at least one of the first terminal and the second terminal to a first temperature lower than the melting point of the connection metal, the first circuit member and the second circuit member A semiconductor device obtained by bonding the first terminal and the second terminal via the connecting metal by pressing each other together.

  According to the present invention, by improving heat resistance, a resin composition and an adhesive film that can realize connection with a connection metal with high reliability can be obtained.

In addition, according to the present invention, a highly reliable connection using the connecting metal can be realized and the circuit members can be connected to each other.
Moreover, according to the present invention, a semiconductor device having a highly reliable connection structure can be obtained.

It is sectional drawing for demonstrating embodiment of the connection method of the circuit member of this invention. It is sectional drawing for demonstrating embodiment of the connection method of the circuit member of this invention. It is sectional drawing for demonstrating embodiment of the connection method of the circuit member of this invention, Comprising: It is a figure which shows the example which laminates | stacks two semiconductor elements on a mounting substrate. It is sectional drawing for demonstrating embodiment of the connection method of the circuit member of this invention, Comprising: It is a figure which shows the example which arranges two semiconductor elements on a mounting board | substrate. It is sectional drawing for demonstrating the 1st modification of the connection method of the circuit member which concerns on embodiment. It is sectional drawing for demonstrating the 2nd modification of the connection method of the circuit member which concerns on embodiment. It is sectional drawing for demonstrating the 3rd modification of the connection method of the circuit member which concerns on embodiment. In Example 1A and Comparative Examples 1A and 2A, it is a figure which shows the state of joining through the bump electrode of the terminals after giving a joining and hardening process. In Example 1C and Reference Example 1C, it is a figure which shows the state of the joining through the bump electrode of the terminals after giving a joining and hardening process.

  Hereinafter, the resin composition, adhesive film, circuit member connection method and semiconductor device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

  First, prior to describing the resin composition and adhesive film of the present invention, the circuit member connecting method of the present invention will be described. In the following, the circuit member connection method of the present invention is applied to the manufacture of a semiconductor device in which a semiconductor element is mounted on a mounting substrate, and an adhesive film is used for mounting the semiconductor element on the mounting substrate. explain.

  One form of the circuit member connection method according to the present embodiment is [1] a mounting substrate 1 (first circuit member), a semiconductor element 2 (second circuit member), a bump electrode 3 (connection metal), and a resin layer 4. And [2] a bonding step of pressing the semiconductor element 2 and the mounting substrate 1 while heating the bump electrode 3 at a temperature lower than its melting point, and [3] a terminal 14 of the mounting substrate 1. And an alloy promoting step for promoting alloying between the terminal 242 of the semiconductor element 2 and the bump electrode 3.

Hereinafter, each process will be described sequentially.
[1] First, the mounting substrate 1 and the semiconductor element 2 (semiconductor component) are prepared (preparation process).
A mounting substrate 1 (first circuit member) shown in FIG. 1 includes a base layer 11, a wiring layer 12, and a protective film 13, which are stacked in this order from the bottom of FIG. In such a mounting substrate 1, the upper surface 152 (first surface) is a mounting surface for mounting the semiconductor element 2. The base layer 11 is made of a semiconductor material such as silicon. The base layer 11 may be formed with circuit elements such as a transistor, a diode, and a resistor (not shown) as necessary.

  The wiring layer 12 electrically connects the semiconductor element 2 mounted on the mounting substrate 1 and the above-described circuit element, electrically connects the semiconductor element 2 or the circuit element, and an external circuit, An electric wiring for electrically connecting the elements or the semiconductor elements 2 is included, thereby forming a circuit.

  Examples of the constituent material of the protective film 13 include resin materials such as polyimide resins, polybenzoxazole resins, polyamide resins, and polyolefin resins, and inorganic dielectric materials such as SiN and SiO. .

  The mounting substrate 1 further includes a terminal 14 (first terminal) provided on the upper surface 152 of the wiring layer 12 and electrically connected to a circuit in the wiring layer 12. The upper end of the terminal 14 protrudes upward from the protective film 13 and is easily brought into contact with the terminal of the semiconductor element 2.

  The mounting substrate 1 is not limited to those described above, and can be replaced by various circuit members such as an organic wiring board, a glass wiring board, and a ceramic wiring board.

  A semiconductor element 2 (second circuit member) shown in FIG. 1 includes a semiconductor chip 21, a wiring layer 22, and a protective film 23, which are stacked in order from the bottom of FIG. In such a semiconductor element 2, the lower surface 251 (second surface) is a mounting surface when mounted on the upper surface 152 of the mounting substrate 1. That is, the semiconductor element 2 is mounted on the mounting substrate 1 face up with the lower surface 251 facing the upper surface 152 of the mounting substrate 1.

The semiconductor chip 21 is made of a semiconductor material such as silicon. Semiconductor chip 2
In 1, circuit elements such as a transistor, a diode, and a resistor (not shown) are formed.

  The wiring layer 22 includes electrical wiring for electrically connecting the above-described circuit elements and for electrically connecting the circuit elements and an external circuit such as the mounting substrate 1. Is formed.

  Moreover, as a constituent material of the protective film 23, the material quoted as a constituent material of the protective film 13 is used, for example.

  The semiconductor element 2 further includes a through electrode 241 provided in a through hole penetrating the semiconductor chip 21 in the thickness direction, and a terminal 242 provided at the lower end of the through electrode 241 and projecting downward from the lower surface 251 of the semiconductor chip 21. (Second terminal) and a terminal 243 provided at the upper end of the through electrode 241 and protruding upward from the upper surface 252 of the semiconductor chip 21. The through electrode 241 is, for example, a TSV (Through-Silicon Via), and the through electrode 241, the terminal 242, and the terminal 243 are electrically connected to each other.

  In addition, the semiconductor element 2 is not limited to the above-mentioned thing, For example, various circuit members, such as an organic wiring board, a glass wiring board, and a ceramic wiring board, can be substituted.

  By stacking the mounting substrate 1 and the semiconductor element 2 as described above, a semiconductor device having a connection structure in which highly reliable electrical bonding is realized can be obtained.

On the other hand, a bump electrode 3 (connection electrode) and a resin layer 4 are also prepared.
Among these, the bump electrode 3 is provided in the terminal 242 of the semiconductor element 2 in this embodiment.

  The bump electrode 3 is, for example, a solder bump, and electrically and mechanically connects the terminal 242 of the semiconductor element 2 and the terminal 14 of the mounting substrate 1.

  Examples of the solder composing the bump electrode 3 include lead-free solder such as Sn—Ag, Sn—Cu, Sn—Zn, and Sn—Ag—Cu. Of these, lead-free solder containing Sn as a main component and Ag as a subcomponent is preferably used. This lead-free solder has higher metal bonding strength and higher connection reliability than other lead-free solders. For this reason, it is useful as a solder constituting the bump electrode 3.

  In addition, although melting | fusing point of the bump electrode 3 changes according to the kind of solder, it is preferable that it is 130-300 degreeC as an example, and it is more preferable that it is 180-230 degreeC. As a result, when the bump electrode 3 is melted, the heat function exerted on other members is kept to a minimum, and the flux function of the resin layer 4 described later is sufficiently developed so that the electrical reliability is high. Connection can be achieved.

  Further, the bump electrode 3 shown in FIG. 1 is provided at the terminal 242 of the semiconductor element 2, but the position where the bump electrode 3 is provided may be provided at the terminal 14 of the mounting substrate 1. 242 and the terminal 14 may be provided.

  The resin layer 4 is provided on the lower surface 251 of the semiconductor element 2 as shown in FIG. The resin layer 4 is provided so as to cover the lower surface 251 and also cover the terminals 242 and the bump electrodes 3.

  This resin layer 4 is formed by sticking (bonding) the resin composition of the present invention or an adhesive film formed from the resin composition to the lower surface 251 of the semiconductor element 2 and has a flux function. ing.

  Therefore, when the bump electrode 3 and the terminal 14 are in contact with each other via the resin layer 4, the resin layer 4 exhibits a flux function due to the heating of the resin layer 4, and between the terminal 242 and the terminal 14 via the bump electrode 3. Can be firmly metal-bonded.

  In addition, the resin layer 4 in the preparation step includes a compound having a flux function and an epoxy resin, and is in an uncured or semi-cured state. The resin layer 4 has moderate heat fluidity and can exclude the resin layer from between the bump electrode 3 and the terminal 14. Further, it can be cured by a subsequent heat treatment (curing treatment).

  In the example of FIG. 1, the resin layer 4 is provided on the lower surface 251 of the semiconductor element 2, but the resin layer 4 may be provided on the upper surface 152 of the mounting substrate 1. It may be provided on both sides.

Hereinafter, the resin layer 4, that is, the resin composition of the present invention will be described in more detail.
The resin layer 4 includes a compound having a flux function and a tris (hydroxyphenyl) methane type epoxy resin as an epoxy resin. In this embodiment, the resin composition includes the following components (a) to (f). Composed of things.

(A) Epoxy resin The epoxy resin is contained in the resin layer 4 so that it is cured by the heat treatment of the resin layer 4, and in the uncured or semi-cured state before the heat treatment, the epoxy resin is moderate. Included to provide good hot fluidity.

  In the present invention, the epoxy resin contains a tris (hydroxyphenyl) methane type epoxy resin (TPM type epoxy resin) represented by the following chemical formula (2).

  In order to improve the heat resistance of the semiconductor device, it is desirable to increase the glass transition point Tg after curing of the cured product of the resin layer 4, that is, the resin composition. For this purpose, an epoxy resin having a rigid structure or a polyfunctional A solid epoxy resin is often used.

  However, when a solid epoxy resin is used, when the resin composition is used in the form of a film, the resin layer 4 before curing becomes brittle and the handling property is lowered, or the thermal fluidity of the resin layer 4 before curing is reduced. The resin may be easily bitten at the time of joining. Among these, the TPM type epoxy resin is excellent in terms of a balance between high Tg after curing, toughness of the resin layer 4 (film) before curing, and further, thermal fluidity in the joining process. In the present invention, a TPM type epoxy resin is contained as the epoxy resin.

  The ratio of the TPM type epoxy resin in the entire epoxy resin is not particularly limited, but is preferably 20% by mass or more and 70% by mass or less, and more preferably 30% by mass or more and 60% by mass or less.

［式中、ｎは、１以上の整数を表す。］

[Wherein n represents an integer of 1 or more. ]

  The average weight molecular weight of the TPM type epoxy resin is not particularly limited, but is preferably 200 or more and 1500 or less, and more preferably 300 or more and 1300 or less. By setting the average weight molecular weight within the above range, it is possible to increase the Tg of the resin layer 4 while imparting excellent heat fluidity to the resin layer 4.

  The content of the TPM type epoxy resin is preferably 5% by mass or more and 20% by mass or less, more preferably 6% by mass or more and 17% by mass or less, and more preferably 7% by mass with respect to the entire resin composition. It is particularly preferably 15% by mass or less. By setting the content of the TPM type epoxy resin to be equal to or higher than the lower limit, it is possible to increase the Tg of the resin layer 4 after curing. Further, by making the content of the TPM type epoxy resin not more than the above upper limit value, it is possible to more accurately suppress or prevent the resin layer 4 from remaining between the terminal 14 and the bump electrode 3. In addition, the handling property of the resin layer (adhesive film) 4 can be improved. Therefore, when the content of the TPM type epoxy resin is within the above-described range, the cured resin layer 4 has particularly excellent heat resistance and reliability. However, the content of the TPM type epoxy resin is not limited to the above-described range.

  In addition, the epoxy resin should just contain the tris (hydroxyphenyl) methane type | mold epoxy resin as an essential component, and may contain the other epoxy resin.

  Examples of such another epoxy resin include a monofunctional epoxy resin containing one epoxy group in one molecule, a bifunctional epoxy resin containing two epoxy groups in one molecule, and one molecule in one molecule. A polyfunctional epoxy resin containing 3 or more epoxy groups can be used, and one or more of them can be used in combination. Among them, 2 or more epoxy groups are contained in one molecule. Preferred are bifunctional epoxy resins and polyfunctional epoxy resins.

  Examples of the bifunctional epoxy resin include diallyl bisphenol A type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, o-allyl bisphenol A type epoxy resin, and the like.

Examples of the polyfunctional epoxy resin include phenol novolac type epoxy resin, cresol novolac type epoxy resin, cresol naphthol type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene skeleton type epoxy resin, 3,3 ′. , 5,5'-tetramethyl 4,4'-dihydroxybiphenyl type epoxy resin, 4,4'-dihydroxybiphenyl type epoxy resin, 1,6-dihydroxybiphenyl type epoxy resin, brominated cresol novolac type epoxy resin, dicyclo Examples thereof include pentadiene type epoxy resins, 1,6 naphthalenediol glycidyl ether epoxy resins, aminophenol triglycidyl ether epoxy resins, and the like. In order to improve the reliability of the resin composition, it is preferable that the ionic impurities (for example, Na ⁺ or Cl ⁻ ) contained in the epoxy resin be as small as possible.

  Further, such other epoxy resin is preferably at least partially liquid at 25 ° C. Thereby, the resin layer 4 can be satisfactorily filled around the terminals 242. Furthermore, the unevenness of the lower surface 251 of the semiconductor element 2 (for example, the unevenness generated by the terminal 242) can be effectively embedded. Furthermore, when it is set as an adhesive film, a softness | flexibility and a flexibility can be provided. For this reason, the adhesive film excellent in the handleability before hardening can be obtained.

  Epoxy resins that are at least partially liquid at 25 ° C. include, for example, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, o-allyl bisphenol A type epoxy resins, 3, 3 ′, 5, 5′-tetramethyl 4,4′-dihydroxybiphenyl type epoxy resin, 4,4′-dihydroxybiphenyl type epoxy resin, 1,6-dihydroxybiphenyl type epoxy resin, phenol novolac type epoxy resin, brominated cresol novolac type epoxy resin Bisphenol type epoxy resin, monoepoxy compound and the like, and one or more of these are included.

The epoxy resin that is at least partially liquid at 25 ° C. preferably has a viscosity at 25 ° C. of 5.0 × 10 ² mPa · s or more and 5.0 × 10 ⁴ mPa · s or less, and has a viscosity at 25 ° C. More preferably, it is 8.0 × 10 ² mPa · s or more and 4.0 × 10 ⁴ mPa · s or less. By making the viscosity at 25 ° C. within the above range, the produced film (resin layer 4) has appropriate flexibility and excellent handling properties.

  In addition, the monofunctional epoxy resin (monoepoxy compound) described above includes, for example, one or more kinds selected from glycidyl ether of 1,6 naphthalene diol, triglycidyl ether of aminophenols, and an epoxy group in the molecule. Have one.

  The other epoxy resin described above is particularly preferably a bisphenol A type epoxy resin or a bisphenol F type epoxy resin. As a result, excellent thermal fluidity can be imparted to the resin layer 4, so that it is possible to more accurately suppress or prevent the resin layer 4 from remaining between the terminal 14 and the bump electrode 3. . Moreover, the handleability of the resin layer 4 can be improved. Furthermore, the resin layer 4 has excellent mechanical properties after curing.

  Furthermore, the resin layer 4 (resin composition) may contain other thermosetting resins in addition to the epoxy resin. Examples of the thermosetting resins include phenoxy resins, cyanate resins, and silicones. Resin, oxetane resin, phenol resin, (meth) acrylate resin, polyester resin (unsaturated polyester resin), diallyl phthalate resin, maleimide resin, polyimide resin (polyimide precursor resin), bismaleimide-triazine resin, etc. Of these, those containing one or more of them are used.

(B) Compound having a flux function The resin composition (resin layer 4) according to the present embodiment contains a compound having a flux function. Thereby, the surface oxide film of the bump electrode 3 can be removed, and electrical connection can be easily performed.

  As will be described later, in the method for manufacturing a semiconductor device of the present embodiment, that is, in step [2] described later, terminals are connected to each other at a relatively low temperature. In order to remove the oxide film on the surface of the solder layer at such a low temperature, it can be said that it is a particularly preferable embodiment to include a compound having the flux function and to select an appropriate blend and an appropriate compound.

  The compound having a flux function is not particularly limited as long as it has a function of removing the oxide film on the solder surface, but a compound having a carboxyl group or both a carboxyl group and a phenolic hydroxyl group is preferable.

  Moreover, an acid anhydride compound can be mentioned as a compound which can express the same effect, even if it does not have a carboxyl group.

  The blending amount of the compound having a flux function in the total solid content of the resin composition is not particularly limited, but is preferably 1% by mass or more and 30% by mass or less, and more preferably 3% by mass or more and 20% by mass or less. preferable. When the compounding amount of the compound having the flux function is within the above range, the flux function can be improved, and when the resin composition is cured, an unreacted epoxy resin or a compound having the flux function remains. Can be prevented, and migration resistance can be improved.

  In addition, among the compounds that act as curing agents for epoxy resins, there are compounds having a flux function (hereinafter, such compounds are also referred to as curing agents having a flux function). For example, aliphatic dicarboxylic acids, aromatic dicarboxylic acids and the like that act as curing agents for epoxy resins also have a flux function. In the present embodiment, a curing agent having such a flux function that acts also as a compound having a flux function and also acts as a curing agent for an epoxy resin can be suitably used.

  In addition, the compound having a flux function having a carboxyl group refers to a compound having one or more carboxyl groups in the molecule, and may be liquid or solid. Further, the compound having a flux function including a carboxyl group and a phenolic hydroxyl group means a compound having one or more carboxyl groups and phenolic hydroxyl groups in the molecule, and may be liquid or solid.

  Of these, examples of the compound having a flux function having a carboxyl group include aliphatic carboxylic acids and aromatic carboxylic acids.

  Examples of the aliphatic carboxylic acid relating to the compound having a flux function having a carboxyl group include a compound represented by the following general formula (1), formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid pivalate, and capryl. Examples include acid, lauric acid, myristic acid, palmitic acid, stearic acid, acrylic acid, methacrylic acid, crotonic acid, oleic acid, fumaric acid, maleic acid, oxalic acid, malonic acid, oxalic acid, and the like.

_{HOOC- (CH 2) n -COOH (} 1)
(In formula (1), n represents an integer of 1 or more and 20 or less.)

Aromatic carboxylic acids related to the compound having a flux function with a carboxyl group include benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, hemimellitic acid, trimellitic acid, trimesic acid, merophanic acid, planitic acid, pyromellitic acid , Merit acid, xylyl acid, hemelic acid, mesitylene acid, prenylic acid, toluic acid, cinnamic acid, salicylic acid (2-hydroxybenzoic acid), 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid Examples include acids, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), 2,6-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, and the like, or derivatives thereof.

  Among these, it is preferable to use a compound having one carboxyl group and one hydroxyl group in the molecule as the compound having a flux function from the balance between the high flux function and the appropriate reactivity with the epoxy resin. Thereby, the metal oxide film on the surface of the bump electrode 3 can be effectively removed even under heating conditions at a relatively low temperature.

  Particularly preferable examples of such compounds include compounds having one phenolic hydroxyl group and one carboxyl group in the molecule, and specifically include salicylic acid (2-hydroxybenzoic acid), 3-hydroxybenzoic acid, 4 -Hydroxybenzoic acid can be mentioned.

  Among these compounds having a flux function having a carboxyl group, the activity of the compound having a flux function, the amount of outgas generated during curing of the resin composition, and the elastic modulus and glass transition temperature of the cured resin composition The compound represented by the general formula (1) is preferable from the viewpoint of good balance. And among the compounds shown by the general formula (1), the compound in which n is 3 to 10 can suppress an increase in the elastic modulus in the resin composition after curing, and the semiconductor chip and the substrate It can use preferably by the point which can improve the adhesiveness of circuit members, such as.

Among the compounds represented by the general formula (1), examples of the compound in which n is 3 to 10 include, for example, n = 3 glutaric acid (HOOC— (CH ₂ ) ₃ —COOH), n = 4 adipic acid _{(HOOC- (CH 2) 4 -COOH} ), n = 5 of pimelic acid _{(HOOC- (CH 2) 5 -COOH} ), sebacic acid of _{n = 8 (HOOC- (CH 2} ) 8 -COOH) , and n = 10 HOOC- (CH ₂ ) ₁₀ —COOH and the like.

  These derivatives are also useful as compounds having a flux function, such as glutaric acid, methyl glutaric acid, dimethyl glutaric acid, methyl adipic acid, dimethyl adipic acid, methyl pimelic acid, dimethyl pimelic acid, methyl sebacic acid, Derivatives such as dimethyl sebacic acid can be used similarly.

  The above-mentioned carboxyl group or a compound having both a carboxyl group and a phenol hydroxyl group is taken in three-dimensionally by reaction with an epoxy resin.

  Therefore, from the viewpoint of improving the formation of a three-dimensional network of the epoxy resin after curing, the compound having a flux function is a curing having a flux activity that acts as a curing agent for the epoxy resin. It is preferable to use an agent. As a hardening | curing agent which has flux activity, the compound provided with the hydroxyl group which can be added to an epoxy resin and the carboxyl group which shows a flux effect | action (oxide film removal effect | action) is mentioned in 1 molecule, for example.

  Examples of the curing agent having such a flux function include salicylic acid (2-hydroxybenzoic acid), 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, and gentidine. Examples include acids (2,5-dihydroxybenzoic acid), 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, and the like. These can be used alone or in combination of two or more.

  Among these, it is preferable to use a compound having one carboxyl group and one hydroxyl group in the molecule as the compound having a flux function from the balance between high flux activity and appropriate reactivity with the thermosetting resin. .

  Thereby, the surface oxide film of the solder layer can be effectively removed even under heating conditions at a relatively low temperature.

  Particularly preferred compounds include compounds having one phenolic hydroxyl group and one carboxyl group in the molecule, and specifically include salicylic acid (2-hydroxybenzoic acid), 3-hydroxybenzoic acid, 4-hydroxybenzoic acid. Mention may be made of hydroxybenzoic acids such as acids.

  Since these compounds are relatively easily available and have extremely high flux activity, they can be particularly preferably used in this embodiment.

  Further, the amount of the curing agent having a flux function in the total solid content of the resin composition is not particularly limited, but is preferably 1% by mass or more and 30% by mass or less, and preferably 1% by mass or more and 20% by mass or less. It is more preferable that When the blending amount of the curing agent having a flux function in the resin composition is within the above range, the flux activity of the resin composition can be improved and the resin composition is stably incorporated into the thermosetting resin. In particular, in the case where hydroxybenzoic acid is included as a curing agent having a flux function, the amount of hydroxybenzoic acid in the total solid content of the resin composition is 1% by mass or more and 5% by mass or less. preferable. Thereby, the said effect can be exhibited more notably. In this case, by including a curing agent having another flux function, the curing agent having a flux function, the total amount is preferably 1% by mass to 30% by mass, and preferably 1% by mass. More preferably, it is 20 mass% or less. Thereby, for example, when phenolphthaline is used as a curing agent having another flux function while maintaining low temperature curing of the resin composition, the cured product of the resin composition can have a high Tg.

  Moreover, as an acid anhydride which has a flux function, an alicyclic acid anhydride, an aromatic acid anhydride, etc., or these derivatives are mentioned.

  Examples of alicyclic acid anhydrides related to the compound having a flux function include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, and trialkyltetrahydrophthalic anhydride. And acid, methylcyclohexene dicarboxylic acid anhydride, and the like or derivatives thereof.

  Examples of the aromatic acid anhydride relating to the compound having a flux function include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, and the like, or derivatives thereof.

  Moreover, it is preferable that the compound which has such a flux function expresses a flux function at 220 degrees C or less, and it is more preferable that it expresses a flux function at 160 degreeC or more and 210 degrees C or less. By using a compound having such a temperature characteristic, when heated at a temperature lower than the melting point of the bump electrode 3 in the next step [2], the compound can reliably exhibit a flux function. Therefore, since the oxide film between the terminal 14 and the bump electrode 3 can be removed, the bonding between the bump electrode 3 and the terminal 14 can be made more reliable.

Further, in a combination with the tris (hydroxyphenyl) methane type epoxy resin represented by the above chemical formula (2) contained as an epoxy resin, a compound in which n is 3 to 10 among the compounds represented by the general formula (1) Alternatively, a derivative thereof is preferable, and among them, n = 8 sebacic acid (HOOC— (CH ₂ ) ₈ —COOH), n = 3 glutaric acid (HOOC— (CH ₂ ) ₃ —COOH), or these It is more preferable that it is a derivative of As a result, as described in detail in the next step [2], alloying and generation of intermetallic compounds accompanied by atomic diffusion between the bump electrode 3 and the terminal 14 and between the bump electrode 3 and the terminal 242, and after The promotion of alloying in step [3] will be performed more reliably.

  Examples of the glutaric acid derivative include 2-methylglutaric acid, 2,2 dimethyl glutaric acid and 3,3 dimethyl glutaric acid.

  Moreover, as a hardening | curing agent which has a flux function, when using the compound shown by the said General formula (1), the hardening | curing agent which has a flux function in the total solid of the resin layer 4 (the compound shown by the said General formula (1)) ) Is preferably 1% by mass or more and 13% by mass or less, and more preferably 5% by mass or more and 13% by mass or less. Thereby, the said effect can be exhibited more notably. In this case, by including a curing agent having another flux function, the curing agent having a flux function, the total amount is preferably 1% by mass to 30% by mass, and preferably 1% by mass. More preferably, it is 20 mass% or less. Thereby, for example, when phenolphthaline is used as a curing agent having another flux function while maintaining low temperature curing of the resin composition, the cured product of the resin composition can have a high Tg.

  Examples of acid anhydrides having a flux function include aliphatic acid anhydrides, alicyclic acid anhydrides, and aromatic acid anhydrides.

  Examples of the aliphatic acid anhydride related to the compound having a flux function include succinic anhydride, polyadipic acid anhydride, polyazeline acid anhydride, polysebacic acid anhydride, and the like.

  Examples of alicyclic acid anhydrides related to the compound having a flux function include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, and trialkyltetrahydrophthalic anhydride. Examples thereof include acid and methylcyclohexene dicarboxylic acid anhydride.

  Examples of aromatic acid anhydrides related to the compound having a flux function include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitate, glycerol tris trimellitate, etc. It is done.

  In addition, when it is set as the structure which uses the epoxy resin containing a TPM type epoxy resin as a thermosetting resin like this invention, the compounding ratio (mass ratio) of an epoxy resin and the compound which has a flux function is not specifically limited. , (Epoxy resin / compound having a flux function) is preferably 0.5 or more and 12 or less, particularly preferably 2 or more and 10 or less. By setting (epoxy resin / compound having a flux function) in the above range, the resin composition can be stably cured, and migration resistance can be improved.

  In the present embodiment, among these compounds having a flux function, one or more from the group consisting of the above-mentioned hydroxybenzoic acid, sebacic acid and glutaric acid or derivatives thereof, phthalic anhydride or phthalic anhydride derivatives Is a preferred embodiment.

(C) Film forming resin The film forming resin improves the film forming property of the resin layer 4. The film-forming resin is soluble in an organic solvent and can form a film alone.

  Examples of the film forming resin include (meth) acrylic resin, phenoxy resin, polyester resin, polyurethane resin, polyimide resin, siloxane-modified polyimide resin, polybutadiene, polypropylene, styrene-butadiene-styrene copolymer, and styrene-ethylene-butylene. -Styrene copolymer, polyacetal resin, polyvinyl butyral resin, polyvinyl acetal resin, butyl rubber, chloroprene rubber, polyamide resin, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-acrylic acid copolymer, acrylonitrile-butadiene-styrene copolymer , Polyvinyl acetate, nylon and the like, and those containing one or more of them are used. Specifically, the film-forming resin preferably contains at least one selected from the group consisting of (meth) acrylic resins, phenoxy resins, and polyimide resins. The film-forming resin may have an epoxy group, a (meth) acryl group, a carboxyl group, a phenolic hydroxyl group, or the like in the structure. The film forming resin is preferably any one of (meth) acrylic resin, phenoxy resin, polyimide resin, and acrylonitrile-butadiene copolymer. In this case, since the film-forming resin is excellent in flexibility, the temperature cycle reliability is improved. In the present embodiment, “(meth) acrylic resin” refers to (meth) acrylic acid polymer, (meth) acrylic acid derivative polymer, (meth) acrylic acid and other monomers. Or a copolymer of a derivative of (meth) acrylic acid and another monomer. Furthermore, “(meth) acrylic acid” means “acrylic acid” or “methacrylic acid”.

  The weight average molecular weight of the film-forming resin is preferably 10,000 or more, more preferably 20,000 to 1,000,000, and even more preferably 30,000 to 900,000. When the weight average molecular weight of the film forming resin is within the above range, the film forming resin can particularly enhance the film forming property of the resin layer 4.

  In addition, when preparing the resin layer 4 as a film, it is preferable that content of film forming resin is 0.5 mass% or more and 50 mass% or less with respect to the whole resin layer 4, 1 mass% or more It is more preferably 40% by mass or less, and further preferably 3% by mass or more and 35% by mass or less. When the content of the film forming resin is within the above range, the fluidity of the resin layer 4 can be suppressed, and the film (resin layer 4) can be easily handled. However, the content of the film forming resin is not limited to the above-described range.

  Depending on the combination of the compound having a flux function contained in the resin layer 4 and the epoxy resin, the addition of the film forming resin to the resin layer 4 can be omitted.

(D) Curing accelerator The curing accelerator promotes curing of the above-described (a) epoxy resin (TPM type epoxy resin).

The curing accelerator is, for example, an imidazole compound. The imidazole compound includes, for example, one or more selected from the group consisting of 2-phenyl-4-methylimidazole, 2-phenylhydroxyimidazole, and 2-phenyl-4-methylhydroxyimidazole. An imidazole compound is preferably used because of its excellent balance between bondability and curability. Furthermore, the imidazole compound preferably has a melting point of 150 ° C. or higher. Thereby, before the curing of the resin layer 4 is completed, the components constituting the bump electrode 3 can easily move on the surface of the terminal 14 or the surface of the terminal 242. Thereby, the electrical connection between the terminal 14 and the bump electrode 3 and the electrical connection between the terminal 242 and the bump electrode 3 can be improved. Examples of the imidazole compound having a melting point of 150 ° C. or higher include 2-phenyl-4-methylimidazole, 2-phenylhydroxyimidazole, 2-phenyl-
4-methylhydroxy imidazole etc. are mentioned, The thing containing 1 type, or 2 or more types of these is used.

  The content of the curing accelerator is preferably 0.005% by mass or more and 10% by mass or less, and more preferably 0.01% by mass or more and 5% by mass or less in the entire resin layer 4. Thereby, it can suppress that the viscosity of the resin layer 4 becomes high too high in the vicinity of the melting temperature of the bump electrode 3. Furthermore, the preservability of the resin layer 4 can be further improved. However, the content of the curing accelerator is not limited to the above-described range.

  Depending on the combination of the compound having a flux function contained in the resin layer 4 and the epoxy resin, the addition of the curing accelerator to the resin layer 4 can be omitted.

(E) Filler The filler reduces the linear expansion coefficient of the resin layer 4 and adjusts the minimum melt viscosity of the resin layer 4. The filler includes, for example, at least one of an organic filler and an inorganic filler. Examples of the organic filler include resin particles and rubber particles. Examples of the constituent material of the inorganic filler include silver, titanium oxide, silica, mica, alumina, aluminum nitride, titanium oxide, silicon nitride, and boron nitride, and one or more of these are used. It is done.

  The filler preferably contains an organic filler from the viewpoint of improving impact resistance. The organic filler used in this case preferably contains, for example, rubber particles containing a rubber component. Examples of the rubber component include acrylic rubber, silicon rubber, butadiene rubber, and the like, and one or more of these are used. Thereby, the toughness of the hardened | cured material of the resin layer 4 can be improved, and the impact resistance of the connection structure of the mounting substrate 1 and the semiconductor element 2 can be improved. The organic filler may have a core-shell structure. As an organic filler having a core-shell structure, for example, organic fine particles (manufactured by Dow Chemical: Paraloid EXL2655 impact resistance enhancer), stress relieving agent (manufactured by Mitsubishi Rayon: Metabrene J-), which are excellent in warpage suppression characteristics of circuit members when bonded, are used. 5800, W-5500) and the like.

  From the viewpoint of improving the reliability of the circuit member connection structure, the filler preferably contains an inorganic filler. Thereby, the linear expansion coefficient of the resin layer 4 can be reduced, and the reliability of the connection structure of a circuit member can be improved. More specifically, the inorganic filler preferably contains silica from the viewpoint of thermal conductivity of the cured resin layer 4. The shape of the silica is, for example, at least one of crushed silica and spherical silica. In the present embodiment, the shape of silica is preferably spherical silica. Furthermore, the inorganic filler preferably contains one or more selected from the group consisting of aluminum oxide, aluminum nitride, titanium oxide, silicon nitride and boron nitride from the viewpoint of thermal conductivity.

  The inorganic filler is preferably a surface-hydrophobized inorganic filler whose surface is modified with a hydrophobic functional group. Thereby, the conformability of the resin component such as the epoxy resin (a) and the compound (b) having a flux function contained in the resin composition and the inorganic filler can be improved. As a result, the resin composition Since the viscosity of the product is reduced and the surface properties of the inorganic filler are improved, the fluidity of the resin composition in the bonding step is improved. In addition, in order to achieve a good bonding state when pressed at a temperature lower than the solder melting point, it is necessary to give the resin fluidity at a lower temperature than before, but surface hydrophobized silica has its high heat flow. It can be suitably used because of its properties.

In the present specification, “hydrophobic” means having a property of having a low affinity for water and being difficult to dissolve in water or to be mixed with water.

  Examples of the surface hydrophobized inorganic filler include those obtained by subjecting the surface of the inorganic filler described above to a silylation treatment. These can use a well-known processing agent (silylation agent) without being restrict | limited at all.

  Examples of the silylating agent include tetramethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane, and n-butyl. Trimethoxysilane, i-butyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, Diphenyldiethoxysilane, i-butyltriethoxysilane, decyltriethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ -Glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ- (2-aminoethyl) ) Alkoxysilanes such as aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, silazanes such as hexamethyldisilazane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, phenyltrichlorosilane, Examples include chlorosilanes such as diphenyldichlorosilane, tert-butyldimethylchlorosilane, and vinyltrichlorosilane. One or more of these can be used in combination.

  In addition, as a treatment agent (hydrophobizing agent) for treating the surface of the inorganic filler in order to obtain a surface hydrophobized inorganic filler, for example, dimethyl silicone oil, methyl hydrogen silicone oil, methyl phenyl silicone oil, alkyl Modified silicone oil, chloroalkyl modified silicone oil, chlorophenyl modified silicone oil, fatty acid modified silicone oil, polyether modified silicone oil, alkoxy modified silicone oil, carbinol modified silicone oil, amino modified silicone oil, fluorine modified silicone oil, and terminal Examples include silicone oils such as reactive silicone oils.

  Furthermore, as the treating agent (hydrophobizing agent), fatty acids and metal salts thereof can be used. Specific examples thereof include undecyl acid, lauric acid, tridecylic acid, dodecylic acid, myristic acid, palmitic acid, pentadecylic acid, stearin. Long chain fatty acids such as acid, heptadecylic acid, arachidic acid, montanic acid, oleic acid, linoleic acid, arachidonic acid, and metal salts such as zinc, iron, magnesium, aluminum, calcium, sodium, and lithium Examples include salts.

  Such a surface-hydrophobized inorganic filler is preferably provided with an alkyl group as a hydrophobic functional group. Thereby, the said effect can be exhibited more notably.

  Examples of the alkyl group include, but are not limited to, methyl group, ethyl group, propyl group, iso-propyl group, butyl group, iso-butyl group, tert-butyl group, sec-butyl group, iso-pentyl group, neo -Pentyl group, tert-pentyl group, iso-hexyl group and the like are mentioned, and among them, at least one of methyl group and ethyl group is preferable. Thereby, the surface of an inorganic filler can be efficiently hydrophobized.

Furthermore, when the above-mentioned surface hydrophobized inorganic filler (for example, surface hydrophobized silica) and tris (hydroxyphenyl) methane type epoxy resin are combined, particularly good connection reliability can be obtained. The reason is that the TPM type epoxy resin exhibits a high Tg, so that it has a high bump protection effect at the time of temperature cycling, and also has a good affinity with the surface hydrophobized inorganic filler, or a relatively high resin fluidity. The bonding level is good. As a result, it is estimated that connection reliability is improved.

  Furthermore, the filler preferably contains both an inorganic filler and an organic filler from the viewpoint of improving the impact resistance and improving the reliability of the circuit member connection structure.

  The average particle diameter of the filler is not particularly limited, but is preferably 500 nm or less, and more preferably 300 nm or less. On the other hand, the lower limit value of the average particle diameter of the filler is, for example, 5 nm. When the average particle diameter of the filler is within the above range, the viscosity of the resin layer 4 can be made moderate. Further, the filler can be prevented from aggregating in the resin layer 4. Furthermore, when the light passes through the resin layer 4, it is possible to reduce the filler from inhibiting visible light transmission. In this case, even if the terminal 242 and the bump electrode 3 are embedded in the resin layer 4, the position of the terminal 242 and the position of the bump electrode 3 can be well recognized using visible light. When the filler contains silica, the visible light transmission is further improved. Thereby, alignment of the semiconductor element 2 becomes easy. However, the average particle diameter of the filler is not limited to the above-described range.

  The average particle diameter of the filler is, for example, the particle diameter when the cumulative particle diameter is 50% in the volume-based particle size distribution obtained by the laser diffraction method.

The content of the filler in the resin layer 4 is preferably 0.1% by mass or more and 80% by mass or less, and more preferably 20% by mass or more and 70% by mass or less. When the content of the filler is within the above range, the linear expansion coefficient difference between the semiconductor element 2 and the resin layer 4 can be reduced after the resin layer 4 is cured. Thereby, the stress which arises between the semiconductor element 2 and the resin layer 4 can be reduced. For this reason, it can suppress more reliably that the semiconductor element 2 peels from the resin layer 4. FIG. Furthermore, it can suppress that the elasticity modulus of the resin layer 4 after hardening becomes it too high that content of a filler exists in the said range. For this reason, the reliability of the connection structure of a circuit member increases. However, the content of the filler is not limited to the above-described range.
In addition, the addition of the filler to the resin layer 4 may be omitted.

(F) Other additive Furthermore, the resin layer 4 may contain components other than (a)-(e) mentioned above as needed. For example, the resin layer 4 according to the present embodiment may include a phenolic curing agent having a weight average molecular weight of 300 or more and 2500 or less. Thereby, the glass transition temperature of the hardened | cured material of the resin layer 4 can be raised, and connection reliability can be improved. Moreover, moderate flexibility can be imparted to the resin layer 4.

  The phenolic curing agent includes, for example, one or more selected from the group consisting of a phenol novolak resin, a cresol novolak resin, a bisphenol A type novolak resin, a bisphenol F type novolak resin, and a bisphenol AF type novolak resin. More specifically, the phenolic curing agent is preferably a phenol novolac resin or a cresol novolac resin.

The content of the phenol-based curing agent is preferably 1% by mass or more and 30% by mass or less, and more preferably 3% by mass or more and 25% by mass or less in the entire resin layer 4. By setting the content of the phenolic curing agent within the above range, the unevenness of the lower surface 251 of the semiconductor element 2 can be effectively embedded in the resin layer 4. Furthermore, the glass transition temperature of the hardened | cured material of the resin layer 4 can be raised effectively by making content of a phenol type hardening | curing agent into the said range. However, content of a phenol type hardening | curing agent is not limited to the range mentioned above.

  The weight average molecular weight of the phenolic curing agent is preferably 300 or more and 2500 or less, and particularly preferably 400 or more and 2300 or less. Thereby, the glass transition temperature of the hardened | cured material of the resin layer 4 can be raised, and also ion migration resistance can be improved efficiently. Moreover, moderate flexibility can be imparted to the resin layer 4. Here, the weight average molecular weight can be measured by GPC (gel permeation chromatogram).

  The resin layer 4 may further contain a silane coupling agent. In this case, the resin layer 4 can be favorably adhered to the semiconductor element 2. The silane coupling agent includes, for example, one or two selected from an epoxy silane coupling agent and an aromatic-containing aminosilane coupling agent. The blending amount of the silane coupling agent is preferably 0.01% by mass or more and 10% by mass or less, more preferably 0.05% by mass or more and 5% by mass or less, and still more preferably in the entire resin layer 4. It is 0.1 mass% or more and 2 mass% or less. However, the compounding amount of the silane coupling agent is not limited to this range.

  The resin layer 4 may further contain an additive in addition to the above components. The additive contains, for example, one or more selected from plasticizers, stabilizers, tackifiers, lubricants, antioxidants, antistatic agents, and pigments.

  The resin layer 4 having such a configuration can be formed, for example, by sticking the adhesive film of the present invention to the lower surface 251 of the semiconductor element 2, and the adhesive films are the above-described (a) to (f). A forming material (resin composition) prepared by mixing or dispersing each of the above components can be formed into a thin film and then dried.

  In addition, the mixing method and dispersion method of each component used when preparing the said forming material are not specifically limited, It can mix or disperse | distribute by a conventionally well-known method. More specifically, for example, the above-described forming material is prepared in a liquid form (varnish) by mixing the above-described components in a solvent or in the absence of a solvent. The solvent used at this time is inactive with respect to each component. Examples of the solvent include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone (DIBK), cyclohexanone and diacetone alcohol (DAA), and aromatics such as benzene, xylene and toluene. Hydrocarbons, alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butyl alcohol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, cellosolves such as ethyl cellosolve acetate, N-methyl-2- Pyrrolidone (NMP), tetrahydrofuran (THF), dimethylformamide (DMF), dibasic acid ester (DBE), ethyl 3-ethoxypropionate (EEP), dimethyl carbonate It includes over preparative (DMC) and the like, those containing one or more of them are used.

  The content of the solvent is preferably adjusted so that the concentration of the mass of the forming material with respect to the sum of the mass of the solvent and the solid content of the forming material is 10 to 80% by mass.

[2] Next, while heating the bump electrode 3 to a temperature lower than its melting point, the semiconductor element 2 is pressed against the mounting substrate 1 from above (joining step; see FIG. 2A). That is, the mounting substrate 1 and the semiconductor element 2 are pressed against each other. At this time, the terminal 14 of the mounting substrate 1 and the terminal 242 of the semiconductor element 2 approach each other and approach each other at a certain distance or more, so that the bump electrode 3 is deformed. As a result, the terminal 14 of the mounting substrate 1 and the terminal 242 of the semiconductor element 2 are joined via the deformed bump electrode 3, thereby mounting (mounting) the semiconductor element 2 on the mounting substrate 1 (FIG. 2B). )reference).

  Thereby, the terminal 14 of the mounting substrate 1 and the bump electrode 3 provided on the terminal 242 of the semiconductor element 2 approach each other and come into contact with each other. At this time, the resin layer 4 interposed between the terminal 14 and the bump electrode 3 is pushed away by the approach of the terminal 14 and the bump electrode 3. As a result, when the terminal 14 and the bump electrode 3 are in contact with each other, the resin layer 4 is removed (pushed away) at the contact point. At this time, since the bump electrode 3 is heated at a temperature lower than its melting point and is not melted, the resin layer 4 is smoothly pushed away by the proximity of the terminal 14 and the bump electrode 3. be able to.

  Under the present circumstances, as this epoxy resin contained in the resin layer 4, in this invention, the tris (hydroxyphenyl) methane type | mold epoxy resin represented by the said Chemical formula (2) is contained. For this reason, the resin layer 4 is more easily pushed away by the approach between the terminal 14 and the bump electrode 3, so that the resin layer 4 can be appropriately prevented from remaining between the terminal 14 and the bump electrode 3. This prevents the bump electrode 3 from spreading over the entire upper surface of the terminal 14. Moreover, Tg of the hardened | cured material of the resin layer 4 can be raised.

  Specifically, the state in which the bump electrode 3 spreads over the entire upper surface of the terminal 14 means that when the semiconductor element 2 is viewed from a direction orthogonal to the stacking direction in which the mounting substrate 1 and the semiconductor element 2 are stacked, the terminal 14 And the terminal 242 are bonded to each other through the bump electrode 3 and the bonding surface is preferably formed with a length of 90% or more with respect to the length of the surface of the terminal 14 or the terminal 242 and is 95% or more. More preferably, the length is more preferably 100%.

  In this step [2], generation of an alloy or an intermetallic compound accompanying atomic diffusion between the bump electrode 3 and the terminal 14 is included. As an epoxy resin, tris (2) represented by the above chemical formula (2) is used. By containing the hydroxyphenyl) methane type epoxy resin, the bump electrode 3 wets and spreads over the entire upper surface of the terminal 14, so that alloying and generation of intermetallic compounds associated with this atomic diffusion are performed more smoothly. be able to.

  Furthermore, by using a tris (hydroxyphenyl) methane type epoxy resin and a liquid epoxy resin such as a bisphenol A type epoxy resin or a bisphenol F type epoxy resin in combination, the resin layer 4 is provided with excellent thermal fluidity. As a result, it is possible to more accurately suppress or prevent the resin layer 4 from remaining between the terminal 14 and the bump electrode 3. Moreover, the handleability of the resin layer 4 can be improved. Furthermore, the resin layer 4 has excellent mechanical properties after curing.

  Therefore, the terminal 14 and the terminal are formed by the alloying or the generation of intermetallic compounds accompanying the atomic diffusion between the bump electrode 3 and the terminal 14 in the present step [2] and the promotion of the alloying in the subsequent step [3]. Since 242 can be firmly bonded to the bump electrode 3, the heat resistance of the obtained semiconductor device can be improved.

  Note that the bonding of the terminal 14 and the terminal 242 via the bump electrode 3 in this step means that the bump electrode 3 accurately eliminates the residual resin layer 4 and wets and spreads over the entire upper surface of the terminal 14. In addition, it means a state in which alloying or generation of an intermetallic compound occurs due to atomic diffusion. On the other hand, the contact or contact via the bump electrode 3 means that the bump electrode 3 does not wet and spread over the entire upper surface of the terminal 14, and alloying and generation of intermetallic compounds accompanying atomic diffusion occur smoothly. Say no state.

  Such a contact or contact state occurs under the conditions of Example 3 of International Publication No. 2011/007531. That is, in Example 3, the second step of contacting the connecting metal electrode and the connecting solder electrode is performed at a temperature of 180 ° C. In this system, the compound having a flux function is used. A compound having low activity is used. For this reason, wetting and spreading of the solder layer does not occur, and the solder layer is only partially in contact with the terminal. In the third embodiment, a step of first “contacting” the terminals using a flip chip bonder is performed. In this step, conditions are set so that the position control of the flip chip bonder also “contacts”. Accordingly, the terminals do not approach each other more than the contact state, so that wetting and spreading do not occur.

  In addition, since the heating temperature in this process is lower than the melting point of the bump electrode 3, significant softening of the resin layer 4 can be suppressed, and the resin layer 4 is prevented from protruding from between the mounting substrate 1 and the semiconductor element 2. can do.

  When the bump electrode 3 is heated, the temperature of the mounting substrate 1 and the semiconductor element 2 rises accordingly. By the way, in the mounting substrate 1 and the semiconductor element 2, the wiring layer and the protective layer are arranged on one side, and the warpage tends to occur at a high temperature due to the non-uniform structure. growing.

  Therefore, as in the present embodiment, the bump electrode 3 is heated to a temperature lower than its melting point, so that the mounting substrate 1 and the semiconductor element 2 can be prevented from greatly warping in this step. Thereby, even when the size of the mounting substrate 1 or the semiconductor element 2 is large, the amount of displacement due to warping can be kept small. As a result, for example, when a plurality of terminal pairs each including the terminal 14 and the terminal 242 are provided, it is possible to prevent the inter-terminal distance from becoming uneven depending on the position of the terminal pair. As a result, the conductivity of each terminal pair can be made uniform.

  Moreover, since the curvature of the mounting substrate 1 and the semiconductor element 2 is suppressed, peeling of the bump electrode 3 from the terminal 14 and the terminal 242 can be accurately suppressed.

  In this step [2], the temperature at which the terminal 14 and the terminal 242 are joined (first temperature) is set lower than the melting point of the bump electrode 3. Therefore, the bump electrode 3 does not melt, but even in such a configuration, an alloy is formed by thermal diffusion of atoms contained in the bump electrode 3 toward the terminal 242 side. Atoms also diffuse into the bump electrode 3 from the terminal 242 side. Further, the bump electrode 3 can be deformed as the terminal 14 and the terminal 242 approach each other. Therefore, the terminal 14 and the terminal 242 are joined via the bump electrode 3.

  Furthermore, the resin layer 4 has a flux function as described above. For this reason, even if an oxide film is formed on the surface of the bump electrode 3, this oxide film is reduced by the flux function of the resin layer 4 and is removed as a result. Therefore, the bonding of the terminal 14 and the terminal 242 via the bump electrode 3 by thermal diffusion of atoms contained in the bump electrode 3 to the terminal 242 side (the atoms are also diffused into the bump electrode 3 from the terminal 242 side). It will be done smoothly.

  As the compound having a flux function contained in the resin layer 4, a compound that exhibits the flux function at a temperature lower than the melting point of the bump electrode 3 is selected. Therefore, even if the heating temperature in this step is set to a low value, such as a temperature lower than the melting point of the bump electrode 3, the resin layer 4 exhibits a flux function, thereby realizing good metal bonding. be able to.

The heating temperature (first temperature) in this step may be lower than the melting point of the bump electrode 3,
When the melting point of the bump electrode 3 is Tm [° C.], it is preferably Tm−5 ° C. or less, and more preferably Tm−10 ° C. or less. More preferably, it is −20 ° C. or lower.

  Thereby, since the bump electrode 3 is not melted, it is possible to avoid the bump electrode 3 from being largely crushed in this step. Moreover, the displacement amount accompanying the curvature of the mounting substrate 1 or the semiconductor element 2 can be suppressed small, and for example, the conductivity of each terminal pair can be made uniform.

  Further, although the bump electrode 3 is not melted, the bump electrode 3 is in a state that can be deformed to some extent by pressing the semiconductor element 2 against the mounting substrate 1. Therefore, at the contact point between the terminal 14 and the bump electrode 3, a resin is used. Layer 4 can be eliminated more efficiently. Furthermore, since the bump electrode 3 is not melted, it is possible to more accurately suppress the bump electrode 3 from being crushed when the semiconductor element 2 is pressed against the mounting substrate 1.

  On the other hand, the lower limit value in this step is not particularly set, but is preferably Tm-70 ° C or higher, and more preferably Tm-45 ° C or higher. Thereby, since the resin layer 4 can be sufficiently softened, the resin layer 4 interposed between the terminal 14 and the bump electrode 3 can be pushed out more reliably. Further, since the flux function of the resin layer 4 is sufficiently developed, the metal oxide film on the surface of the bump electrode 3 can be removed in this step.

  The heating temperature in this step represents the highest temperature reached in the vicinity of the bump electrode 3 with a thermocouple held between the mounting substrate 1 and the semiconductor element 2.

  In addition, the specific heating temperature (first temperature) in this step varies as appropriate according to the melting point of the bump electrode 3, but as an example, it is preferably 160 ° C or higher and 220 ° C or lower, and 180 ° C or higher and 220 ° C or lower. More preferably, it is 180 degreeC or more and 200 degrees C or less.

  In addition, the time for applying pressure while heating in this step (first time) is not particularly limited, but is preferably 0.2 seconds or longer and 60 seconds or shorter, and more preferably 1 second or longer and 30 seconds or shorter. Thereby, even when there are a plurality of terminal pairs, their heating temperatures can be made sufficiently uniform, and the conductivity of each terminal pair can be made uniform. Moreover, sufficient time is secured to push away the resin layer 4.

  The bump electrode 3 is heated by heat conduction through a jig (for example, a flip chip bonder stage or head) for pressing the mounting substrate 1 and the semiconductor element 2 together.

  Moreover, the pressure (first pressure) when pressing the terminal 14 and the terminal 242 together in this step is not particularly limited, but is preferably 50 kPa or more and 500 kPa or less, and more preferably 100 kPa or more and 400 kPa or less. By setting the pressure within the above range, the distance between the terminal 14 and the terminal 242 is sufficiently close, and the resin layer 4 between the terminal 14 and the bump electrode 3 can be more reliably removed. As a result, the terminal 14 and the bump electrode 3 are in contact with each other, and a bonded state in which metal diffusion is started can be created. By forming such a state in this step, when the bump electrode 3 is melted in the step [3] described later, metal bonding (promotion of alloying) is performed quickly even in a short time. . Finally, a highly reliable electrical connection can be achieved between the terminal 14 and the terminal 242 via the bump electrode 3.

Note that the pressure applied when the terminals 14 and 242 are pressed against each other is such that the load applied when the mounting substrate 1 and the semiconductor element 2 are pressed against each other overlaps the upper surface 152 of the mounting substrate 1 and the lower surface 251 of the semiconductor element 2. It is obtained by dividing by the area of the portion (the area of the common portion).

  Further, another semiconductor element 2 may be stacked on the semiconductor element 2 mounted on the mounting substrate 1 as described above, as necessary. Thereby, a laminated body in which a plurality of semiconductor elements 2 are laminated is obtained.

FIG. 3 is a diagram illustrating an example in which two semiconductor elements 2 are stacked on the mounting substrate 1.
In the example shown in FIG. 3, another semiconductor element 2 is stacked on the semiconductor element 2 shown in FIG. The two semiconductor elements 2 have the same configuration. Further, the terminal 243 of the lower semiconductor element 2 and the terminal 242 of the upper semiconductor element 2 are electrically connected via the bump electrode 3. Further, the upper surface 252 of the lower semiconductor element 2 and the lower surface 251 of the upper semiconductor element 2 are bonded via the resin layer 4.

In such an example, the process [2] may be performed also when the upper semiconductor element 2 is stacked on the lower semiconductor element 2. Thereby, even when a plurality of semiconductor elements 2 are stacked, highly reliable electrical connection can be achieved while suppressing the protrusion of the resin layer 4.
The number of stacked semiconductor elements 2 is not particularly limited, but is about 2 to 50.

FIG. 4 is a diagram illustrating an example in which two semiconductor elements 2 are provided on the mounting substrate 1.
In the example shown in FIG. 4, two semiconductor elements 2 are mounted on a single mounting substrate 1 at a predetermined distance. The distance between the semiconductor elements 2 is not limited, but is, for example, about 50 to 500 μm.

  In such an example, when the resin layer 4 protrudes from one semiconductor element 2, depending on the amount of protrusion, it interferes with the mounting region of the other semiconductor element 2, and the mounting of the other semiconductor element 2 is hindered. In addition, a cutting line may be drawn between adjacent mounting regions when the mounting substrate 1 is cut into individual pieces, but the resin layer 4 protrudes from the semiconductor element 2 on the cutting line. In such a case, the cutting tool cannot recognize the cutting line and may not be able to cut.

  Therefore, the above-described problem is solved by suppressing the protrusion of the resin layer 4. As a result, the distance between the semiconductor elements 2 can be shortened. Thereby, high-density mounting of the semiconductor elements 2 mounted on the mounting substrate 1 can be realized, or the number of pieces cut out from one mounting substrate 1 can be increased.

[3] Next, the alloying of the terminal 14 of the mounting substrate 1, the terminal 242 of the semiconductor element 2, and the bump electrode 3 is promoted (alloy promoting step; see FIG. 2C).

  In this step, the method of promoting alloying of the terminal 14, the terminal 242, and the bump electrode 3 is not particularly limited, but for example, the following methods (A) to (C) are preferably used.

Hereinafter, the methods (A) to (C) will be described.
(A) Method for promoting the alloying after the resin layer 4 is cured [A3-1] First, the bump electrode 3 is heated at a temperature lower than the melting point of the bump electrode 3 (bonding and curing step).

  Thereby, the resin layer 4 is cured, and the mounting substrate 1 and the semiconductor element 2 are bonded by the cured resin layer 4. At this time, alloying accompanying atomic diffusion between the bump electrode 3 and the terminal 14 is promoted. That is, the terminal 14 and the terminal 242 are more reliably bonded via the bump electrode 3.

  Here, in the step [2], the mounting substrate 1 and the semiconductor element 2 are laminated in a state in which the occurrence of warpage is suppressed. In this state, the resin layer 4 is formed in the step [A3-1]. Harden. Therefore, the mounting substrate 1 and the semiconductor element 2 are bonded together in a state where the occurrence of warpage is suppressed.

  Moreover, as this epoxy resin contained in the resin layer 4, in the present invention, since the tris (hydroxyphenyl) methane type epoxy resin represented by the chemical formula (2) is contained, the Tg of the resin layer 4 is increased. ing. Therefore, adhesion between the mounting substrate 1 and the semiconductor element 2 by the cured resin layer 4 in this step [A3-1] can be made stronger.

  The heating temperature (second temperature) in this step is set lower than the melting point of the bump electrode 3 as in the step [2]. Note that the second temperature may be higher or lower than the first temperature.

  The specific heating temperature (second temperature) in this step varies as appropriate according to the melting point of the bump electrode 3, but as an example, it is preferably 100 ° C or higher and 250 ° C or lower, more preferably 130 ° C or higher and 240 ° C. Hereinafter, it is more preferably set to 150 ° C. or higher and 200 ° C. or lower.

  Moreover, the time (second time) for applying pressure while heating in this step is not particularly limited, but is set longer than the heating time (first time) in step [2], for example, 1 hour or more and 5 hours or less. It is preferable that it is 2 hours or more and 3 hours or less.

  Furthermore, the atmosphere in this step may be either an air atmosphere or an inert gas atmosphere.

  Further, the pressure of the atmosphere may be under normal pressure or under pressure, for example, preferably set to 0.4 MPa or more and 1.2 MPa or less, more preferably 0.6 MPa or more and 1.0 MPa or less. Set to In addition, generation | occurrence | production of the void in the resin layer 4 can be suppressed or prevented exactly by hardening the resin layer 4 under pressure.

  In addition, the heating temperature (second temperature) in this step may be changed from 150 ° C. to 200 ° C. in the middle of the process, and after heating at 150 ° C. for 2 hours, it is heated at 200 ° C. for 2 hours. It is good also as conditions.

  Alternatively, a pinching member may be used to fix it in accordance with the position in contact with the semiconductor device, and heating may be performed in a non-pressurized state. Thereby, the curvature at the time of hardening can be reduced.

  In addition, this process [A3-1] can be omitted when the curing of the resin layer 4 has progressed and completed in the above-mentioned process [2].

  In this step [A3-1], the alloying of the terminal 14, the terminal 242 and the bump electrode 3 may or may not be promoted.

[A3-2] Next, the terminal 14 of the mounting substrate 1, the terminal 242 of the semiconductor element 2, and the bump electrode 3 are heated. Thereby, alloying of the terminal 14, the terminal 242 and the bump electrode 3 is promoted.

  As a result, the terminal 14 of the mounting substrate 1 and the terminal 242 of the semiconductor element 2 are reliably electrically and mechanically connected via the bump electrode 3.

  Here, in the step [A3-1], the resin layer 4 is already cured. Therefore, even if the terminal 14, the terminal 242, and the bump electrode 3 are heated for alloying, the mounting substrate 1 and the semiconductor element 2 are fixed by the cured resin layer 4. Warpage is suppressed from occurring.

  The specific heating temperature (third temperature) in this step is not particularly limited, but as an example, the solder melting point is preferably −30 ° C. or higher and + 200 ° C. or lower, and the solder melting point is −15 ° C. or higher and + 50 ° C. or lower. It is more preferable that

  Further, the heating time (third time) in this step is not particularly limited, but for example, it is preferably 1 second or longer and 30 minutes or shorter, and more preferably 5 seconds or longer and 10 minutes or shorter.

  By heating under such conditions, alloying of the terminal 14, the terminal 242, and the bump electrode 3 can be promoted more smoothly.

(B) A method of simultaneously curing the resin layer 4 and promoting the alloying [B3-1] In this method (B), the semiconductor device in which the semiconductor element 2 and the mounting substrate 1 are joined is heated. To do. As a result, the resin layer 4 is cured and the alloying of the terminals 14, 242 and the bump electrodes 3 is promoted.

  Thereby, the resin layer 4 is cured, the mounting substrate 1 and the semiconductor element 2 are joined by the cured resin layer 4, and the terminal 14 of the mounting substrate 1 and the terminal 242 of the semiconductor element 2 are connected to the bump electrode 3. And mechanically and mechanically connected to each other.

  Here, in the step [2], the mounting substrate 1 and the semiconductor element 2 are stacked in a state in which the occurrence of warpage is suppressed. In this state, the resin layer 4 is formed in the step [B3-1]. Harden. Therefore, the mounting substrate 1 and the semiconductor element 2 are bonded together in a state where the occurrence of warpage is suppressed.

  Moreover, as this epoxy resin contained in the resin layer 4, in the present invention, since the tris (hydroxyphenyl) methane type epoxy resin represented by the chemical formula (2) is contained, the Tg of the resin layer 4 is increased. ing. Therefore, the bonding between the mounting substrate 1 and the semiconductor element 2 by the cured resin layer 4 in this step [B3-1] can be made stronger.

  The specific heating temperature in this step is not particularly limited as long as the resin layer 4 is cured and the alloying of the terminal 14, the terminal 242, and the bump electrode 3 is performed simultaneously. The melting point is preferably −30 ° C. or higher and + 80 ° C. or lower, and the solder melting point is −15 ° C. or higher and + 50 ° C. or lower.

  In addition, the heating time in this step is not particularly limited, but is preferably, for example, 30 minutes to 5 hours, and more preferably 1 hour to 3 hours.

  Furthermore, the atmosphere in this step may be either an air atmosphere or an inert gas atmosphere.

  Further, the pressure of the atmosphere may be under normal pressure or under pressure, for example, preferably set to 0.4 MPa or more and 1.2 MPa or less, more preferably 0.6 MPa or more and 1.0 MPa or less. Set to In addition, generation | occurrence | production of the void in the resin layer 4 can be suppressed or prevented exactly by hardening the resin layer 4 under pressure.

  By heating under the above conditions, alloying of the terminal 14, the terminal 242 and the bump electrode 3 can be promoted more smoothly.

  Note that in this step, a pinching member may be used, fixed in accordance with a position in contact with the semiconductor device, and heated in a non-pressurized state. Thereby, the curvature at the time of hardening can be reduced.

(C) Method of curing resin layer 4 after promoting the alloying [C3-1] First, the mounting substrate 1 and the semiconductor are heated while heating the semiconductor device in which the semiconductor element 2 and the mounting substrate 1 are joined. The element 2 is pressed against each other with a low load compared to the step [2]. Thereby, alloying of the terminal 14, the terminal 242 and the bump electrode 3 is promoted.

  As a result, the terminal 14 of the mounting substrate 1 and the terminal 242 of the semiconductor element 2 are reliably electrically and mechanically connected via the bump electrode 3.

  Here, in this step [C3-1], the mounting substrate 1 and the semiconductor element 2 are pressed against each other with a lower load than in the step [2]. Therefore, when the alloying of the terminal 14, the terminal 242 and the bump electrode 3 is promoted, the load causes the peeling between the terminal 14, the terminal 242 and the bump electrode 3 due to the semiconductor element warpage at a high temperature. While preventing, it can suppress or prevent that the bump electrode 3 is crushed by the terminal 14 and the terminal 242 exactly.

  Although the specific heating temperature in this process is not particularly limited, as an example, the solder melting point is preferably −30 ° C. or higher and + 160 ° C. or lower, and the solder melting point is −15 ° C. or higher and + 100 ° C. or lower. preferable.

  Further, the heating time (third time) in this step is not particularly limited, but for example, it is preferably 1 second or longer and 30 minutes or shorter, and more preferably 5 seconds or longer and 10 minutes or shorter.

  By heating under such conditions, alloying of the terminal 14, the terminal 242, and the bump electrode 3 can be promoted more smoothly.

  Furthermore, the pressure (second pressure) when the terminal 14 and the terminal 242 are pressed against each other in this step is lower than the pressure (first pressure) in the step [2], specifically, 30 kPa or less, preferably 20 kPa or less, more preferably 10 kPa or less. Thereby, the protrusion of resin can be suppressed.

On the other hand, the lower limit value of the pressure for pressing the terminal 14 and the terminal 242 together in this step may not be set, but is preferably 1 kPa or more, and more preferably 2 kPa or more. Thereby, even if there is a repulsive force of the resin layer 4, the distance between the terminal 14 and the terminal 242 can be easily maintained, so that the molten bump electrode 3, the terminal 14, and the terminal 242 are maintained.
The reliability of the metal bonding that occurs between the two can be further increased.

  Moreover, in the process of cooling after heating to such a temperature, it is preferable to set the pressure when pressing the terminal 14 and the terminal 242 to each other higher than the second pressure.

  In addition, in this process [C3-1], although hardening of the resin layer 4 progresses, it has not reached completion.

  [C3-2] Next, the semiconductor device in which the semiconductor element 2 and the mounting substrate 1 are bonded is heated at a temperature lower than the melting point of the bump electrode 3 (curing step).

  Thereby, the resin layer 4 is cured, and the mounting substrate 1 and the semiconductor element 2 are bonded by the cured resin layer 4.

  Here, the mounting substrate 1 and the semiconductor element 2 are laminated in a state in which the occurrence of warpage is suppressed, and in this state, the resin layer 4 is cured in this step [C3-2]. Therefore, the mounting substrate 1 and the semiconductor element 2 are bonded together in a state where the occurrence of warpage is suppressed.

  Moreover, as this epoxy resin contained in the resin layer 4, in the present invention, since the tris (hydroxyphenyl) methane type epoxy resin represented by the chemical formula (2) is contained, the Tg of the resin layer 4 is increased. ing. Therefore, adhesion between the mounting substrate 1 and the semiconductor element 2 by the cured resin layer 4 in this step [C3-2] can be made stronger.

  The heating temperature (second temperature) in this step is set lower than the melting point of the bump electrode 3 as in the step [2]. Note that the second temperature may be higher or lower than the first temperature.

  The specific heating temperature (second temperature) in this step varies as appropriate according to the melting point of the bump electrode 3, but as an example, it is preferably 100 ° C or higher and 250 ° C or lower, more preferably 130 ° C or higher and 240 ° C. Hereinafter, it is more preferably set to 150 ° C. or higher and 200 ° C. or lower.

  Moreover, the time (second time) for applying pressure while heating in this step is not particularly limited, but is set longer than the heating time (first time) in step [2], for example, 1 hour or more and 5 hours or less. It is preferable that it is 2 hours or more and 3 hours or less.

  Furthermore, the atmosphere in this step may be either an air atmosphere or an inert gas atmosphere.

  Further, the pressure of the atmosphere may be under normal pressure or under pressure, for example, preferably set to 0.4 MPa or more and 1.2 MPa or less, more preferably 0.6 MPa or more and 1.0 MPa or less. Set to In addition, generation | occurrence | production of the void in the resin layer 4 can be suppressed or prevented exactly by hardening the resin layer 4 under pressure.

  In addition, the heating temperature (second temperature) in this step may be changed from 150 ° C. to 200 ° C. in the middle of the process, and after heating at 150 ° C. for 2 hours, it is heated at 200 ° C. for 2 hours. It is good also as conditions.

  Alternatively, a pinching member may be used to fix it in accordance with the position in contact with the semiconductor device, and heating may be performed in a non-pressurized state. Thereby, the curvature at the time of hardening can be reduced.

By passing through the above processes, the laminated body (semiconductor device) formed by laminating the semiconductor element 2 on the mounting substrate 1 is manufactured.
In addition, you may make it seal the semiconductor element 2 with a sealing material as needed.

  Further, when two or more semiconductor elements 2 are provided on the mounting substrate 1, a plurality of semiconductor devices are cut out by dicing the mounting substrate 1 into pieces corresponding to the semiconductor elements 2. Thereby, a plurality of semiconductor devices are manufactured in a lump.

  In the present embodiment, in the step [1], an adhesive film formed using the resin composition containing the components (a) to (f) is attached to the lower surface 251 of the semiconductor element 2. The case where the resin layer 4 is formed has been described, but the resin layer 4 is not limited to the one formed by such a method. For example, the varnish-like resin composition (the resin composition of the present invention) is used as a semiconductor element. 2 may be formed by supplying to the lower surface 251 of the substrate 2 and then drying, or may be formed by supplying the paste-like resin composition to the lower surface 251 of the semiconductor element 2 or the upper surface 152 of the mounting substrate 1. There may be. However, the handling property when forming the resin layer 4 can be improved by sticking the adhesive film to the lower surface 251 to form the resin layer 4 as in the present embodiment.

  Further, in the present embodiment, a case will be described in which the terminal 14 provided in the mounting substrate 1 as the first circuit member and the terminal 242 provided in the semiconductor element 2 as the second circuit member are joined via the bump electrode 3. The mounting substrate 1 has no through electrode, and the semiconductor element 2 has the through electrode 241 that electrically connects the terminal 242 and the terminal 243. However, the present invention is not limited to this configuration, and the first circuit member Each of the second circuit member and the second circuit member may have a through electrode or not.

<First Modification>
FIG. 5 is a cross-sectional view for explaining a first modification of the circuit member connection method according to the embodiment.

  The modification shown in FIG. 5 is different from the circuit member shown in FIGS. 1 to 4 except that the bump electrode 3 is provided on the terminal 14 of the mounting substrate 1 and is not provided on the terminal 242 of the semiconductor element 2. The connection method is the same.

  Even if the position where the bump electrode 3 is provided is changed in this way, the same effect as described above, that is, reliability between the mounting substrate 1 and the semiconductor element 2 is suppressed while suppressing the protrusion of the resin layer 4. High electrical connection can be achieved.

<Second Modification>
FIG. 6 is a cross-sectional view for explaining a second modification of the circuit member connection method according to the embodiment.

  The modification shown in FIG. 6 is different from the circuit member connection method shown in FIGS. 1 to 4 except that the bump electrode 3 is provided on both the terminal 242 of the semiconductor element 2 and the terminal 14 of the mounting substrate 1. It is the same.

  Even if the position where the bump electrode 3 is provided is changed in this way, the same effect as described above, that is, reliability between the mounting substrate 1 and the semiconductor element 2 is suppressed while suppressing the protrusion of the resin layer 4. High electrical connection can be achieved.

<Third Modification>
FIG. 7 is a cross-sectional view for explaining a third modification of the circuit member connection method according to the embodiment.

  The modification shown in FIG. 7 is different from that shown in FIG. 1 except that the semiconductor element 2 is used in place of the mounting substrate 1, that is, the semiconductor elements 2 are stacked and the semiconductor elements 2 are turned upside down. It is the same as the connection method of the circuit member shown to -4. In other words, in the present modification, when two semiconductor elements 2 are stacked, the element surface of the upper semiconductor element 2 (the surface on the side where the wiring layer 22 is provided with respect to the semiconductor chip 21) is lower. They are stacked face down so as to face the semiconductor element 2 side.

  Specifically, in the semiconductor element 2 according to this modification, the protective film 23, the wiring layer 22, and the semiconductor chip 21 are stacked in this order from the bottom of FIG. In addition, the semiconductor element 2 according to this modification includes a through electrode 241 that penetrates the semiconductor chip 21 in the thickness direction, and a terminal 243 that is provided at the lower end of the through electrode 241 and protrudes downward from the lower surface of the semiconductor chip 21. And a terminal 242 provided at the upper end of the through electrode 241 and protruding upward from the upper surface of the semiconductor chip 21.

  Here, in this modification, the bump electrode 3 is provided on the terminal 243 of the semiconductor element 2.

  Even when the stacking surface (mounting surface) of the semiconductor elements 2 is changed in this way, the same effect as described above, that is, while the protrusion of the resin layer 4 is suppressed, between the semiconductor elements 2 (between circuit members) A reliable electrical connection can be achieved.

  The resin composition, the adhesive film, the circuit member connection method, and the semiconductor device of the present invention have been described above. However, the present invention is not limited to this, and the semiconductor device may be any device that can exhibit the same function. It can be replaced with the configuration of Moreover, arbitrary components may be added.

  The adhesive film may include a protective layer that protects the resin layer on at least one of the one surface and the other surface of the resin layer.

  Furthermore, in the circuit member connection method, an arbitrary step may be added to the embodiment.

Hereinafter, specific examples of the present invention will be described.
1. 1. Examination of types of epoxy resin 1-1. Preparation of raw materials First, raw materials used in the resin compositions of Examples and Comparative Examples are shown below.
Unless otherwise specified, the amount of each component is part by mass.

(Phenol novolac resin)
As a phenol novolac resin, “PR-55617” manufactured by Sumitomo Bakelite Co., Ltd. was prepared.

(Epoxy resin 1A)
As the epoxy resin 1A, a tris (hydroxyphenyl) methane type epoxy resin (manufactured by Mitsubishi Chemical Corporation: “jER 1032H60”) was prepared.

(Epoxy resin 2A)
As the epoxy resin 2A, a cresol novolak type epoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd .: “YDCN-800-70”) was prepared.

(Epoxy resin 3A)
A fluorene type epoxy resin (manufactured by Osaka Gas Chemical Co., Ltd .: “OGSOL CG-500”) was prepared as the epoxy resin 3A.

(Compound 1A having a flux function)
4-hydroxybenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as compound 1A having a flux function.

(Compound 2A having a flux function)
Phenolphthalene (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as compound 2A having a flux function.

(Film-forming resin 1)
As the film-forming resin 1, a bisphenol A type phenoxy resin (manufactured by Nippon Kayaku Epoxy Manufacturing Co., Ltd .: “YP-50”) was prepared.

(Curing accelerator 1)
As the curing accelerator 1, 2-phenyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd .: “2P4MZ”) was prepared.

(Filler 1)
As filler 1, a spherical silica filler (manufactured by Admatechs Co., Ltd .: “SC1050”) was prepared.

1-2. Preparation of sample for evaluation (Example 1A)
[1A] Preparation of resin layer <Preparation of resin varnish>
First, as a phenol novolac resin, an epoxy resin, a compound having a flux function, a film-forming resin, a curing accelerator, and a filler, those shown in Table 1 were weighed in parts by mass shown in Table 1, respectively, A resin varnish having a component concentration of 50% by mass was prepared by dissolving and dispersing in methyl ethyl ketone.

<Production of resin film (resin layer)>
The obtained resin varnish is applied to a base polyester film (base film, trade name: Lumirror) to a thickness of 50 μm, dried at 100 ° C. for 5 minutes, and a flux of 25 μm thickness. A resin film (resin layer) having a function was obtained.

[2A] Preparation of Member Next, a silicon wafer on which circuit elements and wirings were formed was prepared. Note that a Cu pad is exposed on the silicon wafer, and a bump electrode made of SnAg-based lead-free solder having a melting point of 221 ° C. is provided on the pad.

Next, the resin film prepared in [1A] was attached to a silicon wafer so as to cover the bump electrodes. And the base polyester film was peeled and only the resin film was transferred.

  Next, the silicon wafer on which the resin film was attached was cut into individual pieces together with the resin film to obtain a semiconductor element with the resin film. The obtained semiconductor element had a size of 10 mm × 10 mm and a thickness of 0.3 mm.

  On the other hand, a silicon mounting board having a Cu pad (terminal) with Ni / Au plating formed on the surface was prepared. The mounting board had a size of 6 inches and a thickness of 0.625 mm.

[3A] Connection between members Next, a semiconductor element with a resin film was picked up by a flip chip bonder and placed on a mounting substrate.

  In this process, first, the semiconductor element was pressed against the mounting substrate at 10 N for 10 seconds while heating the bump electrode to 180 ° C.

Subsequently, the semiconductor element and the mounting substrate that had undergone the bonding process were heated at 180 ° C. in a 0.8 MPa nitrogen atmosphere for 2 hours (3A-1: bonding and curing process). Thereafter, the bump electrode was heated at 240 ° C. for 5 seconds to promote alloying in the bump electrode 3 (3A-2: alloy promotion step).
As described above, an evaluation sample obtained by stacking semiconductor elements on a mounting substrate was obtained.

(Comparative Examples 1A, 2A)
In the production of the [1A] resin layer, the phenol novolak resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler shown in Table 1 are the masses shown in Table 1, respectively. A sample for evaluation was obtained in the same manner as in Example 1A except that the sample was weighed.

1-3. Evaluation of Sample for Evaluation 1-3. 1 Evaluation of Connectivity in Joining Step First, when obtaining samples for evaluation of Examples and Comparative Examples, joining and curing step [3A-1] between members [3A] The degree of bonding of the terminals through the bump electrode at the time when the process was completed was observed with an electron microscope.
FIG. 8 shows the state of bonding through the bump electrodes between the terminals, which was observed with an electron microscope.

1-3-2 Evaluation of Connection Reliability Next, the evaluation samples obtained in the examples and the comparative examples were each subjected to a reflow test. In this reflow test, the evaluation sample is exposed to 260 ° C. for 5 seconds and then returned to room temperature, and then this cycle is performed for 5 cycles.

  And before implementing a reflow test, the presence or absence of the generation | occurrence | production of the crack in the bump electrode of the sample for evaluation after completion of five cycles was observed with the electron microscope. And based on the observation result, it evaluated in light of the following evaluation criteria.

<Evaluation criteria for connection reliability>
○: No crack was observed in the reflow of 5 cycles.
X: Generation of cracks is observed in 5 cycles of reflow.
The evaluation results are shown in Table 1.

  As is clear from FIG. 8, in both the example and each comparative example, when the semiconductor element is viewed from the direction orthogonal to the stacking direction in which the mounting substrate and the semiconductor element are stacked, the terminals are bonded via the bump electrodes. The joining surface was formed with a length of 90% or more with respect to the length of the surface of the terminal, and it was considered that the connectivity in the connecting step was good in both the examples and the comparative examples.

On the other hand, as shown in Table 1, in the connection reliability by the reflow test, the example shows an excellent result, and the reliability between the terminals included in the semiconductor element and the mounting substrate via the bump electrode is high. Although high electrical connection is performed, each comparative example shows a result inferior to the example, and highly reliable electrical connection is achieved via the bump electrode between the terminals provided on the semiconductor element and the mounting substrate. It showed results that couldn't be said.

  That is, by using a TPM type epoxy resin as an epoxy resin, the bump electrode is less likely to be deteriorated as compared with the case where another epoxy resin is used. It was found that reliable electrical connection can be made through the bump electrodes.

  This is because the connectivity in the connection process does not seem to differ so much, but it is in a good bonded state with few resin bites, and as a result, in the bonding process, the atoms between the bump electrode and the terminal Alloying accompanying diffusion and generation of intermetallic compounds are performed more smoothly, and further, the cured resin component firmly surrounds the bump electrode, thereby stably protecting the bump electrode. It is guessed that it originates from the above.

2. 2. Examination of types of compounds having flux function 2-1. Preparation of raw materials First, raw materials used in the resin compositions of the respective examples are shown below.
Unless otherwise specified, the amount of each component is part by mass.

(Phenol novolac resin)
As a phenol novolac resin, “PR-55617” manufactured by Sumitomo Bakelite Co., Ltd. was prepared.

(Epoxy resin 1B)
As the epoxy resin 1B, a tris (hydroxyphenyl) methane type epoxy resin (manufactured by Mitsubishi Chemical Corporation: “jER 1032H60”) was prepared.

(Compound 1B having a flux function)
4-hydroxybenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as the compound 1B having a flux function.

(Compound 2B having a flux function)
Phenolphthalin (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as compound 2B having a flux function.

(Compound 3B having a flux function)
As compound 3B having a flux function, 4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 70/30 (manufactured by Shin Nippon Chemical Co., Ltd., “Licacid MH-700”) was prepared.

(Compound 4B having a flux function)
As compound 4B having a flux function, trialkyltetrahydrophthalic anhydride (manufactured by Mitsubishi Chemical Corporation, “YH-307”) was prepared.

(Compound 5B having a flux function)
As compound 5B having a flux function, glutaric acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared.

(Compound 6B having a flux function)
Sebacic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as the compound 6B having a flux function.

(Film-forming resin 1)
As the film-forming resin 1, a bisphenol A type phenoxy resin (manufactured by Nippon Kayaku Epoxy Manufacturing Co., Ltd .: “YP-50”) was prepared.

(Curing accelerator 1)
As the curing accelerator 1, 2-phenyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd .: “2P4MZ”) was prepared.

(Filler 1)
As filler 1, a spherical silica filler (manufactured by Admatechs Co., Ltd .: “SC1050”) was prepared.

2-2. Preparation of sample for evaluation (Example 1B)
[1B] Preparation of resin layer <Preparation of resin varnish>
First, as a phenol novolac resin, an epoxy resin, a compound having a flux function, a film-forming resin, a curing accelerator, and a filler, those shown in Table 2 were weighed in parts by mass shown in Table 2, respectively. A resin varnish having a component concentration of 50% by mass was prepared by dissolving and dispersing in methyl ethyl ketone.

<Production of resin film (resin layer)>
The obtained resin varnish is applied to a base polyester film (base film, trade name: Lumirror) to a thickness of 50 μm, dried at 100 ° C. for 5 minutes, and a flux of 25 μm thickness. A resin film (resin layer) having a function was obtained.

[2B] Preparation of Member Next, a silicon wafer on which circuit elements and wirings were formed was prepared. Note that a Cu pad is exposed on the silicon wafer, and a bump electrode made of SnAg-based lead-free solder having a melting point of 221 ° C. is provided on the pad.

  Next, the resin film prepared in [1B] was attached to a silicon wafer so as to cover the bump electrodes. And the base polyester film was peeled and only the resin film was transferred.

  Next, the silicon wafer on which the resin film was attached was cut into individual pieces together with the resin film to obtain a semiconductor element with the resin film. The obtained semiconductor element had a size of 10 mm × 10 mm and a thickness of 0.3 mm.

  On the other hand, a silicon mounting board having a Cu pad (terminal) with Ni / Au plating formed on the surface was prepared. The mounting board had a size of 6 inches and a thickness of 0.625 mm.

[3B] Connection between members Next, a semiconductor element with a resin film was picked up by a flip chip bonder and placed on a mounting substrate.

  In this process, first, while heating the bump electrode to 200 ° C., the semiconductor element was pressed against the mounting substrate at 10 N for 10 seconds.

Subsequently, the semiconductor element and the mounting substrate that had undergone the bonding process were heated at 180 ° C. in a 0.8 MPa nitrogen atmosphere for 2 hours (3B-1: bonding and curing process). Thereafter, the bump electrode was heated at 240 ° C. for 5 seconds to promote alloying in the bump electrode 3 (3B-2: alloy promotion step).
As described above, an evaluation sample obtained by stacking semiconductor elements on a mounting substrate was obtained.

(Examples 2B-5B)
In the production of the [1B] resin layer, the phenol novolac resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler shown in Table 2 are the masses shown in Table 2, respectively. A sample for evaluation was obtained in the same manner as in Example 1B except that it was weighed in the section.

2-3. Evaluation of Evaluation Sample 2-3-1. Evaluation of Connection Reliability Next, the evaluation samples obtained in Examples and Comparative Examples were each subjected to a reflow test. In this reflow test, the evaluation sample is exposed to 260 ° C. for 5 seconds and then returned to room temperature, and then this cycle is performed for 5 cycles.

  And before implementing a reflow test, the presence or absence of the generation | occurrence | production of the crack in the bump electrode of the sample for evaluation after completion of five cycles was observed with the electron microscope. And based on the observation result, it evaluated in light of the following evaluation criteria.

<Evaluation criteria for connection reliability>
○: No crack was observed in the reflow of 5 cycles.
X: Generation of cracks is observed in 5 cycles of reflow.
The evaluation results are shown in Table 2.

  As shown in Table 2, in the connection reliability by the reflow test, each example shows an excellent result, and a highly reliable electrical connection between the terminals of the semiconductor element and the mounting substrate via the bump electrode The result obtained is obtained.

3. 3. Examination of temperature conditions in joining process 3-1. Preparation of raw materials First, raw materials used in the resin compositions of Examples and Reference Examples are shown below.
Unless otherwise specified, the amount of each component is part by mass.

(Phenol novolac resin)
As a phenol novolac resin, “PR-55617” manufactured by Sumitomo Bakelite Co., Ltd. was prepared.

(Epoxy resin 1C)
As the epoxy resin 1C, a tris (hydroxyphenyl) methane type epoxy resin (manufactured by Mitsubishi Chemical Corporation: “jER 1032H60”) was prepared.

(Compound 1C having a flux function)
Glutaric acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as Compound 1C having a flux function.

(Film-forming resin 1)
As the film-forming resin 1, a bisphenol A type phenoxy resin (manufactured by Nippon Kayaku Epoxy Manufacturing Co., Ltd .: “YP-50”) was prepared.

(Curing accelerator 1)
As the curing accelerator 1, 2-phenyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd .: “2P4MZ”) was prepared.

(Filler 1)
As filler 1, a spherical silica filler (manufactured by Admatechs Co., Ltd .: “SC1050”) was prepared.

3-2. Preparation of sample for evaluation (Example 1C)
[1C] Preparation of resin layer <Preparation of resin varnish>
First, as a phenol novolac resin, an epoxy resin, a compound having a flux function, a film-forming resin, a curing accelerator, and a filler, those shown in Table 3 were weighed in parts by mass shown in Table 3, respectively. A resin varnish having a component concentration of 50% by mass was prepared by dissolving and dispersing in methyl ethyl ketone.

<Production of resin film (resin layer)>
The obtained resin varnish is applied to a base polyester film (base film, trade name: Lumirror) to a thickness of 50 μm, dried at 100 ° C. for 5 minutes, and a flux of 25 μm thickness. A resin film (resin layer) having a function was obtained.

[2C] Preparation of Member Next, a silicon wafer on which circuit elements and wirings were formed was prepared. Note that a Cu pad is exposed on the silicon wafer, and a bump electrode made of SnAg-based lead-free solder having a melting point of 221 ° C. is provided on the pad.

Next, the resin film prepared in [1C] was attached to a silicon wafer so as to cover the bump electrodes. And the base polyester film was peeled and only the resin film was transferred.

  Next, the silicon wafer on which the resin film was attached was cut into individual pieces together with the resin film to obtain a semiconductor element with the resin film. The obtained semiconductor element had a size of 10 mm × 10 mm and a thickness of 0.3 mm.

  On the other hand, a silicon mounting board having a Cu pad (terminal) with Ni / Au plating formed on the surface was prepared. The mounting board had a size of 6 inches and a thickness of 0.625 mm.

[3C] Connection between members Next, a semiconductor element with a resin film was picked up by a flip chip bonder and placed on a mounting substrate.

  In this process, first, the semiconductor element was pressed against the mounting substrate at 30 N for 10 seconds while the bump electrode was heated to 200 ° C.

Then, the semiconductor element and mounting board which passed through the joining process were heated for 2 hours in 180 degreeC and 0.8 Mpa nitrogen atmosphere (3C-1: joining and hardening process). Thereafter, the bump electrode was heated at 240 ° C. for 5 seconds to promote alloying in the bump electrode 3 (3C-2: alloy promotion step).
As described above, an evaluation sample obtained by stacking semiconductor elements on a mounting substrate was obtained.

(Reference Example 1C)
In the bonding and curing step [3C-1] in the connection of the [3C] members, the conditions for pressing the semiconductor element against the mounting substrate are as follows: An evaluation sample was obtained in the same manner as in Example 1C except that the conditions for pressing the element were used.

3-3. Evaluation of Evaluation Samples 3-3.1 Evaluation of Connectivity of Evaluation Samples First, for the evaluation samples of Examples and Reference Examples, at the time when the joining and curing step [3C-1] was completed, respectively, terminals The degree of joining via the bump electrodes was observed with an electron microscope. FIG. 9 shows the state of bonding through the bump electrodes between the terminals, which was observed with an electron microscope.

  As is apparent from FIG. 9, in the evaluation sample of the example, when the semiconductor element is viewed from the direction orthogonal to the stacking direction in which the mounting substrate and the semiconductor element are stacked, the terminals are bonded via the bump electrodes. The joining surface is formed with a length of 95% or more with respect to the length of the surface of the terminal, and a joining surface that can be said to be sufficiently joined to each other through the bump electrode is formed. On the other hand, in the sample for evaluation of the reference example, when the semiconductor element is viewed from a direction orthogonal to the stacking direction in which the mounting substrate and the semiconductor element are stacked, the bonding surface where the terminals are bonded via the bump electrode is The result is that the terminal is formed only with a length of less than 90% with respect to the length of the surface of the terminal, and the terminals are not sufficiently bonded to each other via the bump electrode, that is, via the bump electrode. The result of abutting or touching is shown.

  That is, by setting the heating temperature in the bonding step to be 21 ° C. lower than the melting point Tm of the bump electrode, the terminals are connected to each other as compared with the case where the heating temperature in the bonding step is 81 ° C. lower than the melting point Tm of the bump electrode. It was possible to sufficiently bond via the bump electrode.

  Although not shown in the figure, when the heating temperature in the bonding step is lower than the melting point Tm of the bump electrode by less than 20 ° C., a cured resin composition is formed between the mounting substrate and the semiconductor element. It showed a tendency to leak. Therefore, in the bonding process, the temperature at which the bump electrodes are heated is set to be 20 ° C. or more and 70 ° C. or less lower than the melting point Tm of the bump electrodes, so that the connectivity between the terminals via the bump electrodes in the evaluation sample is It was found that it can be good.

4). 4. Examination of hydrophobic treatment of filler 4-1. Preparation of raw materials First, raw materials used in the resin compositions of the respective examples are shown below.
Unless otherwise specified, the amount of each component is part by mass.

(Phenol novolac resin)
As a phenol novolac resin, “PR-55617” manufactured by Sumitomo Bakelite Co., Ltd. was prepared.

(Epoxy resin 1D)
As the epoxy resin 1D, a tris (hydroxyphenyl) methane type epoxy resin (manufactured by Mitsubishi Chemical Corporation: “jER 1032H60”) was prepared.

(Compound 1D having flux function)
As compound 1D having a flux function, glutaric acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared.

(Film-forming resin 1)
As the film-forming resin 1, a bisphenol A type phenoxy resin (manufactured by Nippon Kayaku Epoxy Manufacturing Co., Ltd .: “YP-50”) was prepared.

(Curing accelerator 1)
As the curing accelerator 1, 2-phenyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd .: “2P4MZ”) was prepared.

(Filler 1D)
As the filler 1D, a spherical silica filler (manufactured by Admatechs Co., Ltd .: “SC1050”) was prepared.

(Filler 2D)
As the filler 1, a hydrophobic treated spherical silica filler (manufactured by Tokuyama Corporation: “SSP-02M”) was prepared.

4-2. Preparation of sample for evaluation (Example 1D)
[1D] Preparation of resin layer <Preparation of resin varnish>
First, as a phenol novolac resin, an epoxy resin, a compound having a flux function, a film-forming resin, a curing accelerator, and a filler, those shown in Table 4 were weighed in parts by mass shown in Table 4, respectively, A resin varnish having a component concentration of 50% by mass was prepared by dissolving and dispersing in methyl ethyl ketone.

<Production of resin film (resin layer)>
The obtained resin varnish is applied to a base polyester film (base film, trade name: Lumirror) to a thickness of 50 μm, dried at 100 ° C. for 5 minutes, and a flux of 25 μm thickness. A resin film (resin layer) having a function was obtained.

[2D] Preparation of Member Next, a silicon wafer on which circuit elements and wirings were formed was prepared. Note that a Cu pad is exposed on the silicon wafer, and a bump electrode made of SnAg-based lead-free solder having a melting point of 221 ° C. is provided on the pad.

  Next, the resin film prepared in [1D] was attached to a silicon wafer so as to cover the bump electrodes. And the base polyester film was peeled and only the resin film was transferred.

  Next, the silicon wafer on which the resin film was attached was cut into individual pieces together with the resin film to obtain a semiconductor element with the resin film. The obtained semiconductor element had a size of 10 mm × 10 mm and a thickness of 0.3 mm.

  On the other hand, a silicon mounting board having a Cu pad (terminal) with Ni / Au plating formed on the surface was prepared. The mounting board had a size of 6 inches and a thickness of 0.625 mm.

[3D] Connection Between Members Next, a semiconductor element with a resin film was picked up by a flip chip bonder and placed on a mounting substrate.

  In this process, first, the semiconductor element was pressed against the mounting substrate at 30 N for 10 seconds while the bump electrode was heated to 200 ° C.

Then, the semiconductor element and mounting board which passed through the joining process were heated for 2 hours in 180 degreeC and 0.8 Mpa nitrogen atmosphere (3D-1: joining and hardening process). Thereafter, the bump electrode was heated at 240 ° C. for 5 seconds to promote alloying in the bump electrode 3 (3D-2: alloy promotion step).
As described above, an evaluation sample obtained by stacking semiconductor elements on a mounting substrate was obtained.

(Example 2D)
In the production of the [1D] resin layer, the phenol novolac resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler shown in Table 4 are the masses shown in Table 4, respectively. A sample for evaluation was obtained in the same manner as in Example 1D except that it was weighed in the part.

4-3. Evaluation of Evaluation Sample 4-3.1 Evaluation of Connection Reliability Next, each of the evaluation samples obtained in each example was subjected to a reflow test. In this reflow test, an evaluation sample is exposed to 260 ° C. for 5 seconds and then returned to room temperature, and then this cycle is performed for 10 cycles.

  And before implementing a reflow test, the presence or absence of the generation | occurrence | production of the crack in the bump electrode of the sample for evaluation after completion of 5 cycles after completion of 10 cycles was observed with the electron microscope. And based on the observation result, it evaluated in light of the following evaluation criteria.

<Evaluation criteria for connection reliability>
(Double-circle): Generation | occurrence | production of a crack is not recognized in any of reflow of 5 cycles and 10 cycles.
◯: Cracks are not observed in 5 cycles of reflow, but cracks are observed in 10 cycles of reflow.
X: Generation of cracks is observed in both 5 cycles and 10 cycles of reflow.
The evaluation results are shown in Table 4.

  As shown in Table 4, in each connection reliability in the reflow test, each example shows an excellent result, and a highly reliable electrical connection through the bump electrode between the terminals provided in the semiconductor element and the mounting substrate In particular, in Example 2D, a result showing better connection reliability was obtained.

  That is, by using a combination of a TPM type epoxy resin as an epoxy resin and a surface hydrophobized inorganic filler as an inorganic filler, a TPM type epoxy resin and a filler whose surface is not hydrophobized It was found that more reliable electrical connection can be made between the terminals provided on the semiconductor element and the mounting substrate via the bump electrode, as compared with the above combination.

5). Review of other evaluations 5-1. Preparation of raw materials First, raw materials used in the resin compositions of the examples and comparative examples are shown below.
Unless otherwise specified, the amount of each component is part by mass.

(Phenol novolac resin)
As a phenol novolac resin, “PR-55617” manufactured by Sumitomo Bakelite Co., Ltd. was prepared.

(Epoxy resin 1E)
As the epoxy resin 1E, a liquid bisphenol A type epoxy resin (manufactured by DIC Corporation: “EPICLON-840S”) was prepared.

(Epoxy resin 2E)
As the epoxy resin 2E, a liquid bisphenol F type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd .: “YL983U”) was prepared.

(Epoxy resin 3E)
As the epoxy resin 3E, a tris (hydroxyphenyl) methane type epoxy resin (manufactured by Mitsubishi Chemical Corporation: “jER 1032H60”) was prepared.

(Epoxy resin 4E)
As the epoxy resin 4E, a naphthalene type epoxy resin (manufactured by DIC Corporation: “EPICLONP-4700”) was prepared.

(Epoxy resin 5E)
A fluorene type epoxy resin (manufactured by Osaka Gas Chemical Co., Ltd .: “OGSOL CG-500”) was prepared as the epoxy resin 5E.

(Compound 1E having a flux function)
As compound 1E having a flux function, 3-hydroxybenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared.

(Compound 2E having a flux function)
4-hydroxybenzoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as the compound 2E having a flux function.

(Compound 3E having flux function)
Phenolphthalene (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared as compound 3E having a flux function.

(Film-forming resin 1)
As the film-forming resin 1, a bisphenol A type phenoxy resin (manufactured by Nippon Kayaku Epoxy Manufacturing Co., Ltd .: “YP-50”) was prepared.

(Curing accelerator 1)
As the curing accelerator 1, 2-phenyl-4-methylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd .: “2P4MZ”) was prepared.

(Filler 1)
As filler 1, a spherical silica filler (manufactured by Admatechs Co., Ltd .: “SC1050”) was prepared.

5-2. Preparation of sample for evaluation (Example 1E)
[1E] Preparation of resin layer <Preparation of resin varnish>
First, as a phenol novolac resin, an epoxy resin, a compound having a flux function, a film-forming resin, a curing accelerator, and a filler, those shown in Table 5 were weighed in parts by mass shown in Table 5, respectively. A resin varnish having a component concentration of 50% by mass was prepared by dissolving and dispersing in methyl ethyl ketone.

<Production of resin film (resin layer)>
The obtained resin varnish is applied to a base polyester film (base film, trade name: Lumirror) to a thickness of 50 μm, dried at 100 ° C. for 5 minutes, and a flux of 25 μm thickness. A resin film (resin layer) having a function was obtained.

[2E] Preparation of member Next, a silicon wafer on which circuit elements and wirings were formed was prepared. Note that a Cu pad is exposed on the silicon wafer, and a bump electrode made of SnAg-based lead-free solder having a melting point of 221 ° C. is provided on the pad.

  Next, the resin film prepared in [1E] was attached to a silicon wafer so as to cover the bump electrodes. And the base polyester film was peeled and only the resin film was transferred.

  Next, the silicon wafer on which the resin film was attached was cut into individual pieces together with the resin film to obtain a semiconductor element with the resin film. The obtained semiconductor element had a size of 10 mm × 10 mm and a thickness of 0.3 mm.

  On the other hand, a silicon mounting board having a Cu pad (terminal) with Ni / Au plating formed on the surface was prepared. The mounting board had a size of 6 inches and a thickness of 0.625 mm.

[3E] Connection between members Next, a semiconductor element with a resin film was picked up by a flip chip bonder and placed on a mounting substrate.

In this process, first, the semiconductor element was pressed against the mounting substrate at 20 N for 2 seconds while the bump electrode was heated to 200 ° C. (bonding step).

Subsequently, the semiconductor element and the mounting substrate that had undergone the bonding process were heated at 180 ° C. in a 0.8 MPa nitrogen atmosphere for 2 hours (3E-1: bonding and curing process). Thereafter, the bump electrode was heated at 240 ° C. for 5 seconds to promote alloying in the bump electrode 3 (3E-2: alloy promotion step).
As described above, an evaluation sample obtained by stacking semiconductor elements on a mounting substrate was obtained.

(Example 2E)
In the production of the [1E] resin layer, the phenol novolac resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler, each of those shown in Table 5 and the mass shown in Table 5 In the connection between the [3E] members, evaluation was performed in the same manner as in Example 1E except that the steps from the joining and curing steps to obtaining the evaluation sample were changed as follows. A sample was obtained.

(Process from joining and curing process to obtaining evaluation sample)
The semiconductor element and the mounting substrate that have undergone the bonding process are heated at 260 ° C. and 0.5 N for 5 seconds to promote alloying, and then the semiconductor element and the mounting substrate are further heated at 180 ° C. in a 0.8 MPa nitrogen atmosphere. The resin layer was cured by heating for 2 hours.

(Example 3E)
In the production of the [1E] resin layer, the phenol novolac resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler, each of those shown in Table 5 and the mass shown in Table 5 In the connection between the [3E] members, the steps from the joining step and the joining and curing step to obtaining the evaluation sample are the same as in the case of Example 1E, except that the steps from obtaining the evaluation sample are as follows. Thus, a sample for evaluation was obtained.

(Joining process)
While heating the bump electrode to 190 ° C., the semiconductor element was pressed against the mounting substrate at 20 N for 2 seconds.

(Process from joining and curing process to obtaining evaluation sample)
The semiconductor element and the mounting substrate that had undergone the bonding step were heated at 220 ° C. in a 0.8 MPa nitrogen atmosphere for 2 hours. This cured the resin film and promoted alloying.

(Comparative Example 1E)
In the production of the [1E] resin layer, the phenol novolac resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler, each of those shown in Table 5 and the mass shown in Table 5 In the connection between the [3E] members, the steps from the joining step and the joining and curing step to obtaining the evaluation sample are the same as in the case of Example 1E, except that the steps from obtaining the evaluation sample are as follows. Thus, a sample for evaluation was obtained.

(Joining process)
While heating the bump electrode to 240 ° C., the semiconductor element was pressed against the mounting substrate at 20 N for 5 seconds.

(Process from joining and curing process to obtaining evaluation sample)
The semiconductor element and the mounting substrate that had undergone the bonding step were heated at 180 ° C. in a 0.8 MPa nitrogen atmosphere for 2 hours. Thereby, the resin film was hardened.

(Comparative Example 2E)
In the production of the [1E] resin layer, the phenol novolac resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler, each of those shown in Table 5 and the mass shown in Table 5 In the connection between the [3E] members, the steps from the joining step and the joining and curing step to obtaining the evaluation sample are the same as in the case of Example 1E, except that the steps from obtaining the evaluation sample are as follows. Thus, a sample for evaluation was obtained.

(Joining process)
While the bump electrode was heated to 210 ° C., the semiconductor element was pressed against the mounting substrate at 20 N for 2 seconds.

(Process from joining and curing process to obtaining evaluation sample)
The semiconductor element and the mounting substrate that had undergone the bonding step were heated at 180 ° C. in a 0.8 MPa nitrogen atmosphere for 2 hours. Thus, after the resin film was cured, the bump electrode was heated at 220 ° C. for 10 minutes using an oven.

(Comparative Example 3E)
In the production of the [1E] resin layer, the phenol novolac resin, the epoxy resin, the compound having a flux function, the film-forming resin, the curing accelerator, and the filler, each of those shown in Table 5 and the mass shown in Table 5 In the connection between the [3E] members, the steps from the joining step and the joining and curing step to obtaining the evaluation sample are the same as in the case of Example 1E, except that the steps from obtaining the evaluation sample are as follows. Thus, a sample for evaluation was obtained.

(Joining process)
While the bump electrode was heated to 180 ° C., the semiconductor element was pressed against the mounting substrate at 20 N for 2 seconds.

(Process from joining and curing process to obtaining evaluation sample)
The semiconductor element and the mounting substrate that had undergone the bonding step were heated at 180 ° C. in a 0.8 MPa nitrogen atmosphere for 2 hours. Thereby, after hardening a resin film, the bump electrode was heated at 260 degreeC for 5 second, and the bump electrode 3 was reflowed.

5-3. Evaluation of Sample for Evaluation 5-3.1 Evaluation of Handling Properties of Resin Film First, the handling properties of the resin films obtained in the respective Examples and Comparative Examples were measured and evaluated in light of the following evaluation criteria.

<Evaluation criteria for resin film handling>
◯: No cracks are generated when the resin film is bent 180 °.
X: Cracks occur when the resin film is bent 180 °.
The evaluation results are shown in Table 5.

5-3.2 Evaluation of Connectivity First, with respect to the samples for evaluation obtained in the examples and the comparative examples, the regions where the terminals were connected to each other by the bump electrodes were observed using an optical microscope. And it evaluated in light of the following evaluation criteria by the connection state of the terminals by the bump electrode in this observed area | region.

<Evaluation criteria for connectivity>
A: Observing 20 connection terminals, there is no terminal whose resin bite is 1/3 or more of the terminal width.
A: 20 connection terminals are observed, and there is no terminal whose resin bite is 1/2 or more of the terminal width.
×: 20 connection terminals are observed, and one or more terminals having a resin bite of ½ or more of the terminal width are present.
The evaluation results are shown in Table 5.

5-3.3 Evaluation of Tg of Resin Layer First, regarding the resin layers included in the samples for evaluation obtained in each Example and each Comparative Example, a TMA apparatus (product name “TMA / The Tg was measured using SS6000 "). And it evaluated in light of the following evaluation criteria by Tg of the measured resin layer.

<Evaluation criteria for Tg>
○: It is 120 ° C. or higher. X: Less than 120 ° C. The evaluation results are shown in Table 5.

5-3.4 Evaluation of Connection Reliability Next, 20 evaluation samples obtained in each example and each comparative example were prepared. These were then subjected to a temperature cycle test. In this temperature cycle test, an evaluation sample is exposed to −55 ° C. for 30 minutes and then exposed to 125 ° C. for 30 minutes as one cycle, and this is repeated for 100 cycles.

  Next, the continuity test of the sample for evaluation subjected to the temperature cycle test was performed, the sample was further cut, and the cut surface near the bump electrode was observed with an electron microscope. And the inspection result was evaluated in light of the following evaluation criteria.

<Evaluation criteria for connection reliability>
A: There is no conduction problem in the continuity test. Moreover, the cross section of 20 connection terminals is confirmed, and a crack etc. are not confirmed inside an electrode.
○: No continuity problem in continuity test. Moreover, the cross section of 20 connection terminals is confirmed, and one or more that the crack has generate | occur | produced inside an electrode exist.
X: A disconnection occurred in the continuity test. One or more bonding states between the bump electrode and the terminal are defective.
The evaluation results are shown in Table 5.

As is clear from Table 5, in each example, that is, the circuit member connection method according to the present invention, excellent results were obtained in all of the handling properties of the resin film, the connectivity, the Tg of the resin layer, and the connection reliability. It was confirmed that a highly reliable electrical connection was achieved between the semiconductor element and the mounting substrate.

  On the other hand, each comparative example shows a result inferior to each example in any of the handling properties, connectivity, resin layer Tg and connection reliability of the resin film, between the semiconductor element and the mounting substrate. Results showed that reliable electrical connections were not made.

DESCRIPTION OF SYMBOLS 1 Mounting substrate 2 Semiconductor element 3 Bump electrode 4 Resin layer 11 Base layer 12 Wiring layer 13 Protective film 14 Terminal 21 Semiconductor chip 22 Wiring layer 23 Protective film 152 Upper surface 241 Through electrode 242 Terminal 243 Terminal 251 Lower surface 252 Upper surface

Claims (1)

A first circuit member comprising: a first surface; and a first terminal provided on the first surface side;
Interposing between a second circuit member comprising a second surface and a second terminal provided on the second surface side,
While heating the connection metal provided on at least one of the first terminal and the second terminal to a first temperature lower than the melting point of the connection metal, the first circuit member and the second circuit member A resin composition having a flux function, which is used when the first terminal and the second terminal are joined to each other via the connection metal,
A resin composition comprising a compound having a flux function and an epoxy resin, wherein the epoxy resin contains a tris (hydroxyphenyl) methane type epoxy resin.

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