JP2015052051A - Epoxy resin composition, and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an epoxy resin composition which effectively prevents the generation of voids, can form an insulation section excellent in bondability with a circuit board and an electronic component, and can be used for manufacture of a semiconductor device having high reliability, and to provide a semiconductor device which effectively prevents generation of voids, has an insulation section excellent in bondability with a circuit board and an electronic component, and has high reliability.SOLUTION: An epoxy resin composition is used for manufacture of a semiconductor device, and contains: a liquid epoxy resin having two or more epoxy groups in the molecule; a curing agent; an inorganic filler; and a pre-gelating agent consisting of a vinyl polymer. The pre-gelation agent has a content of 2.0 wt.% or more and 20 wt.% or less, and gelates before the epoxy resin is cured when heated at 190°C.

Description

  The present invention relates to an epoxy resin composition and a semiconductor device.

  In recent years, electronic components such as IC chips have been required to be mounted at high density on circuit boards such as printed wiring boards in order to further reduce the size and increase the functionality of electronic devices. Flip chip mounting is widely known as one of the effective means for increasing the mounting density.

  Usually, in flip chip mounting, a plurality of terminals on an electronic component and predetermined terminals on a circuit board are aligned through protrusions called bumps, and then electrical connections between these terminals are formed in a lump. Thereafter, a resin composition (underfill material) having electrical insulation is injected and cured between the electronic component and the circuit board. As the underfill material, a liquid resin composition containing an epoxy resin is widely used. However, in the above method, since the connection of the terminal and the curing of the resin composition are performed separately, there is a problem that the manufacturing efficiency is low. there were.

  Therefore, after applying a liquid epoxy resin to the surface of the circuit board, the electronic component is placed on the epoxy resin coating layer and heated and pressed from the back of the electronic component to cure the terminal connection and the resin composition in the same process. A pressure welding method has been proposed (see, for example, Patent Document 1).

  However, until now, when the pressure welding method is employed, there is a problem that bubbles (voids) are generated inside the cured resin (cured portion).

JP-A-10-120761

  An object of the present invention is to effectively prevent the generation of voids and form an insulating portion having excellent bonding properties with a circuit board and an electronic component, and is used for manufacturing a highly reliable semiconductor device. The present invention provides a highly reliable semiconductor device having an insulating portion excellent in bondability with a circuit board and an electronic component while effectively preventing generation of voids. There is.

Such an object is achieved by the present invention described in the following (1) to (13).
(1) An epoxy resin composition used for manufacturing a semiconductor device,
A liquid epoxy resin having two or more epoxy groups in the molecule, a curing agent, an inorganic filler, and a pregelling agent composed of a vinyl polymer;
The pregelator content is 2.0 wt% or more and 20 wt% or less,
An epoxy resin composition characterized by gelling before being cured by the epoxy resin when heated at 190 ° C.

  As a result, generation of voids can be effectively prevented, and an insulating part having excellent bonding properties with circuit boards and electronic components can be formed. Epoxy that can be used for manufacturing a highly reliable semiconductor device A resin composition can be provided.

  (2) The epoxy resin composition according to (1), wherein the epoxy resin includes a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and an aminophenol epoxy resin.

  As a result, the viscosity stability at room temperature can be made particularly excellent, the permeability at the time of application of the epoxy resin composition can be made particularly excellent, and further, generation of voids due to gelation Can be prevented more reliably.

(3) The content of the bisphenol A type epoxy resin is 0.5 wt% or more and 4.0 wt% or less,
The content of the bisphenol F type epoxy resin is 7.0% by weight or more and 40% by weight or less,
The epoxy resin composition according to the above (2), wherein the content of the aminophenol epoxy resin is 10% by weight or more and 30% by weight or less.

  Thereby, the affinity of an epoxy resin and a pregelling agent can be made especially excellent, and the effect by including a pregelling agent is exhibited more notably. Moreover, the wettability of the epoxy resin composition with respect to an electronic component or a circuit board can be made especially excellent, and generation | occurrence | production of a void can be prevented more effectively.

  (4) The epoxy resin composition according to (2) or (3), wherein the epoxy resin further contains a 1,6-hexanediol epoxy resin.

  Thereby, the affinity of an epoxy resin and a pregelling agent can be made further excellent, and the effect by including a pregelling agent is exhibited more notably. Moreover, the wettability of the epoxy resin composition with respect to an electronic component or a circuit board can be further improved, and the generation of voids can be more effectively prevented.

  (5) The epoxy resin composition according to (4), wherein the content of the 1,6-hexanediol epoxy resin is 1.0% by weight or more and 6.0% by weight or less.

  Thereby, the affinity of an epoxy resin and a pregelling agent can be made further excellent, and the effect by including a pregelling agent is exhibited more notably. Moreover, the wettability of the epoxy resin composition with respect to an electronic component or a circuit board can be further improved, and the generation of voids can be more effectively prevented.

  (6) The epoxy resin composition has a viscosity at 25 ° C. of 20 Pa · s or less, and when heated at 190 ° C., the time until gelation starts is within 5 seconds (1) to (5 The epoxy resin composition according to any one of items 1).

  As a result, it is possible to more effectively prevent void entrainment while more effectively suppressing the generation of voids due to volatile components.

  (7) The epoxy resin composition according to any one of (1) to (6), wherein the curing agent is a solid dispersion type amine adduct curing agent.

  Thereby, at the time of preservation | save of an epoxy resin composition, the curing reaction of an epoxy resin can be efficiently advanced by heating, while preventing the unintentional reaction of an epoxy resin more reliably. Moreover, the timing with which an epoxy resin hardens | cures and gelatinization of an epoxy resin composition at the time of heating an epoxy resin composition can be adjusted to a more suitable thing. Further, the hardness of the cured product can be made particularly excellent. Further, the storage stability as a one-pack type (non-mixed type) epoxy resin composition can be made particularly excellent, and the long-term storage in a state where each component is mixed can be made particularly excellent. it can.

  (8) The epoxy resin composition according to any one of (1) to (7), wherein the content of the curing agent is 3% by weight or more and 30% by weight or less.

  Thereby, the bondability (bonding strength) with the circuit board and electronic component of the hardened | cured part formed can be made especially excellent, preventing generation | occurrence | production of the void at the time of hardening more effectively.

  (9) The epoxy resin composition according to any one of (1) to (8), wherein the pregelator has a weight-average molecular weight of acetone-soluble component of 100,000 to 20 million.

  As a result, high gelling properties can be expressed even with a relatively small content, and the stability of the shape of the epoxy resin composition after gelation can be made particularly excellent and dissolved in the epoxy resin. It is possible to achieve a sufficient gel state in a short time.

  (10) The epoxy resin composition according to any one of (1) to (9), wherein the acetone-soluble component of the pregelator is 2.0% by weight or more and 35% by weight or less.

  This makes it possible to more effectively suppress a decrease in the glass transition temperature of a cured product obtained by curing the epoxy resin composition, while making the gelation characteristics during heating sufficiently excellent. The reliability of the obtained semiconductor device can be made particularly excellent.

  (11) The pregelling agent includes, as monomer components, methyl methacrylate: 70% by weight to 99% by weight and vinyl monomers other than methyl methacrylate: 1% by weight to 30% by weight (1) The epoxy resin composition of any one of (10) thru | or (10).

  Thereby, the affinity of an epoxy resin and a pregelling agent can be made especially excellent, and the effect by including a pregelling agent is exhibited more notably. Moreover, the wettability of the epoxy resin composition with respect to an electronic component or a circuit board can be made especially excellent, and generation | occurrence | production of a void can be prevented more effectively.

  (12) The vinyl monomer other than the methyl methacrylate is one or two selected from the group consisting of a carboxyl group-containing vinyl monomer, a hydroxyl group-containing vinyl monomer, and a glycidyl group-containing vinyl monomer. The epoxy resin composition according to the above (11), which contains the above functional group-containing monomer.

  Thereby, the affinity of an epoxy resin and a pregelling agent can be made further excellent, and the effect by including a pregelling agent is exhibited more notably. Moreover, the wettability of the epoxy resin composition with respect to an electronic component or a circuit board can be further improved, and the generation of voids can be more effectively prevented.

  (13) A semiconductor device manufactured using the epoxy resin composition according to any one of (1) to (12).

  Accordingly, generation of voids can be effectively prevented, and a highly reliable semiconductor device having an insulating portion excellent in bondability with a circuit board and an electronic component can be provided.

  According to the present invention, generation of voids can be effectively prevented, and an insulating portion excellent in bondability with a circuit board and an electronic component can be formed, and used for manufacturing a highly reliable semiconductor device. The present invention provides a highly reliable semiconductor device having an insulating portion excellent in bondability with a circuit board and an electronic component while effectively preventing generation of voids. be able to.

It is sectional drawing which shows typically suitable embodiment of the manufacturing method of the semiconductor device of this invention. It is the figure which showed an example of the time-dependent change of the viscosity of an epoxy resin composition at the time of heating the epoxy resin composition of this invention at a fixed temperature increase rate, and reaction calorie | heat amount.

DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
<< Semiconductor Device Manufacturing Method >>
First, an example of a method for manufacturing a semiconductor device of the present invention will be described.

  FIG. 1 is a cross-sectional view schematically showing a preferred embodiment of a method for manufacturing a semiconductor device of the present invention.

  As shown in FIG. 1, in the manufacturing method of the present embodiment, a circuit board preparation step (1 a) for preparing a circuit board (wiring board) 4 including a substrate 5 and a plurality of terminals 6, and terminals 6 of the circuit board 4 include An epoxy resin composition application step (1b) for applying an epoxy resin composition 8 ′ to the provided surface side, and a terminal (bump) of a semiconductor chip (electronic component) 1 including a substrate 2 and a plurality of terminals (bumps) 3 ) 3 is pressed and heated by the bonding tool 9 in a state where the surface provided with 3 faces the surface to which the epoxy resin composition 8 ′ of the circuit board 4 is applied. While joining the terminal (bump) 3 and the terminal 6 of the circuit board 4, it has the press-contacting process (1c) which hardens epoxy resin composition 8 'and makes it the hardening part (insulating part) 8. FIG. Thereby, the semiconductor device 100 is obtained (1d).

<Circuit board>
The circuit board 4 includes a board 5 and a plurality of terminals 6.

  The substrate 5 is composed of, for example, various glasses, various ceramics, semiconductor materials such as Si, various resin materials, or any combination thereof.

  The thickness (average) of the substrate 5 is not particularly limited, but is preferably 20 μm or more and 3 mm or less.

  Further, the substrate 5 is not limited to a single layer, but may be a multilayer structure.

  A wiring pattern 60 made of a conductive material (for example, Au, Sn, Cu, ITO, or an alloy containing these) is provided on one surface 51 side of the substrate 5. The end portions of the wiring pattern (lead) 60 constitute each terminal 6.

  Note that the wiring pattern 60 may be formed inside the substrate 5 when the substrate 5 is formed of a laminate of a plurality of layers.

<Epoxy resin composition application process>
In the epoxy resin composition application step, the epoxy resin composition 8 ′ is applied to the side of the circuit board 4 on which the terminals 6 are provided.

  The epoxy resin composition 8 'is applied in a single liquid state on the circuit board 4, and two or more liquids are not mixed on the circuit board 4. This is advantageous from the viewpoint of preventing the generation of voids.

  Examples of the method for applying the epoxy resin composition 8 ′ include dispensing application, printing application, transfer application, and the like.

The application amount of the epoxy resin composition 8 ′ is preferably adjusted so as to form an appropriate fillet for a semiconductor chip (electronic component) having a plurality of terminals (bumps) 3.
The epoxy resin composition 8 ′ of the present invention will be described in detail later.

<Pressing process>
First, the semiconductor chip 1 used in this step will be described.

(Semiconductor chip)
The semiconductor chip 1 has a substrate 2 and a plurality of terminals (bumps) 3 provided on one surface (lower surface) side of the substrate 2.

  The substrate 2 is made of a semiconductor material such as Si, for example. Although the thickness of the board | substrate 2 is not specifically limited, It is preferable that they are 30 micrometers or more and 1000 micrometers or less. Moreover, the board | substrate 2 may be comprised not only with what was comprised by the single layer but by the laminated body of a some layer.

  An integrated circuit (not shown) is formed on one surface 21 side of the substrate 2, and this integrated circuit is covered with a passivation film (insulating film) 212. A part of the wiring pattern 211 of the integrated circuit is exposed from the passivation film 212, and the terminal 3 is disposed so as to contact the exposed portion (pad) of the wiring pattern 211.

  The wiring pattern 211 is made of a conductive material (for example, Al, Cu, W, Mo, Si, Ni, Au, or an alloy containing these). The wiring pattern 211 may be a single layer film of these materials or a multilayer film in which two or more layers are laminated.

The passivation film 212 is made of, for example, silicon oxide (SiO ₂ ), silicon nitride (Si—N), polyimide, other oxides, nitrides, oxynitrides, and the like. The passivation film 212 may be a single layer film of these materials or a multilayer film in which two or more layers are stacked.

  The integrated circuit may be formed on the other surface 22 side of the substrate 2 or may be formed on both the surface 21 side and the surface 22 side. Further, in the case where the substrate 2 is configured by a stacked body of a plurality of layers, the integrated circuit may be formed inside the substrate 2.

  The constituent material of the terminal 3 is not particularly limited as long as it has conductivity. For example, Ni, Au, Ag, Cu, Al, Sn, P, B, Bi, In, Zn, or an alloy containing them Etc.

  Each of the terminals 3 is set to have substantially the same thickness (height), and the thickness is not particularly limited, but is preferably 15 μm or more and 25 μm or less.

  Moreover, the terminal 3 is formed so that a cross-sectional area becomes substantially constant along the thickness direction. As a result, it is possible to cope with the narrow pitch (increasing the wiring density of the terminals), which is required as electronic devices have higher performance and smaller size.

  In addition, the terminal 3 may be configured by a single layer or may be a laminated body including a plurality of layers.

(Pressurization / heating conditions)
The pressure applied to the semiconductor chip 1 by the bonding tool 9 is preferably 0.5 Pa or more and 5 Pa or less. Thereby, the connection reliability between the circuit board 4 and the semiconductor chip 1 can be made particularly excellent.

  The heating temperature by the bonding tool 9 is preferably 160 ° C. or higher and 220 ° C. or lower, and more preferably 180 ° C. or higher and 200 ° C. or lower. Thereby, the connection reliability between the circuit board 4 and the semiconductor chip 1 can be made particularly excellent, the heating time by the bonding tool 9 can be shortened, and the productivity of the semiconductor device 100 is particularly excellent. Can be. In the present invention, the epoxy resin composition defines the relationship between the timing of gelation of the epoxy resin composition at 190 ° C. and the timing of curing of the epoxy resin, but the heating temperature is a value within the above range. If it exists, since the relationship similar to the relationship of the gelatinization timing of the epoxy resin composition in 190 degreeC and the timing of hardening of an epoxy resin can be satisfied, the effect of this invention can be acquired reliably.

  The heating time by the bonding tool 9 is preferably 2 seconds or longer and 20 seconds or shorter, and more preferably 3 seconds or longer and 10 seconds or shorter. Thereby, the connection reliability between the circuit board 4 and the semiconductor chip 1 can be made particularly excellent, and the productivity of the semiconductor device 100 can be made particularly excellent.

  As will be described in detail later, the epoxy resin composition 8 ′ of the present invention contains a pregelling agent that satisfies a predetermined condition at a predetermined content, thereby reliably preventing generation of voids. The bonding strength of the hardened portion 8 to the circuit board 4 and the semiconductor chip 1 can be made excellent.

<Semiconductor device>
The semiconductor device of the present invention is obtained by sealing a semiconductor element using the epoxy resin composition of the present invention described in detail later.

Accordingly, generation of voids can be effectively prevented, and a highly reliable semiconductor device having an insulating portion excellent in bondability with a circuit board and an electronic component can be provided. In this specification, the term “bondability” refers to properties related to bonding such as bonding strength and bonding reliability.
The semiconductor device of the present invention can be manufactured using, for example, the method described above.

<< Epoxy resin composition >>
Next, preferred embodiments of the epoxy resin composition of the present invention will be described in detail.

  FIG. 2 is a diagram showing an example of the change over time in the viscosity of the epoxy resin composition and the amount of reaction heat when the epoxy resin composition of the present invention is heated at a constant rate of temperature increase.

  In recent years, electronic components such as IC chips have been required to be mounted at high density on circuit boards such as printed wiring boards in order to further reduce the size and increase the functionality of electronic devices. Flip chip mounting is widely known as one of the effective means for increasing the mounting density.

  Usually, in flip chip mounting, a plurality of terminals on an electronic component and predetermined terminals on a circuit board are aligned through protrusions called bumps, and then electrical connections between these terminals are formed in a lump. Thereafter, a resin composition (underfill material) having electrical insulation is injected and cured between the electronic component and the circuit board. As the underfill material, a liquid resin composition containing an epoxy resin is widely used. However, in the above method, since the connection of the terminal and the curing of the resin composition are performed separately, there is a problem that the manufacturing efficiency is low. there were.

  Therefore, after applying a liquid epoxy resin to the surface of the circuit board, the electronic component is placed on the epoxy resin coating layer and heated and pressed from the back of the electronic component to cure the terminal connection and the resin composition in the same process. A pressure welding method has been proposed.

  However, until now, when the pressure welding method is employed, there is a problem that bubbles (voids) are generated inside the cured resin (cured portion).

  Therefore, the present inventor has intensively studied for the purpose of solving the above-mentioned problems, and has arrived at the present invention. That is, the epoxy resin composition of the present invention includes an epoxy resin having two or more epoxy groups in a molecule, a curing agent, a filler, and a pregelling agent composed of a vinyl polymer. The content of the agent is 2.0% by weight or more and 20% by weight or less, and when heated at 190 ° C., it is gelled before the epoxy resin is cured. Thereby, even when the low boiling point component is vaporized when the epoxy resin is cured, the generation of voids is effectively prevented by effectively preventing entry into the formed cured portion. It is possible to provide an epoxy resin composition that can form an insulating portion excellent in bondability with a circuit board and an electronic component and can be used for manufacturing a highly reliable semiconductor device.

  On the other hand, when the above conditions are not satisfied, the excellent effects as described above cannot be obtained.

  For example, when the epoxy resin composition does not contain a predetermined pregelling agent or contains a predetermined pregelling agent, the epoxy resin composition has a pregelling agent content of less than a predetermined value. By heating for the effect, it is impossible to reliably prevent bubbles from being generated and voids from being formed in the formed cured portion.

  Moreover, when the content rate of a pregelling agent exceeds predetermined value, when manufacturing a semiconductor device, the bonding property (bonding strength) with respect to the circuit board and electronic component of the hardened | cured part (insulating part) formed is enough. It cannot be made excellent. When the content of the pregelling agent exceeds a predetermined value, the curing rate of the epoxy resin becomes too fast, resulting in variations in the bonding of the bumps, resulting in problems in the electrical connection of the terminal connection.

  Further, even when the epoxy resin composition contains a pregelling agent, the pregelling agent does not satisfy a predetermined relationship between the timing of gelation of the epoxy resin composition and the timing of curing of the epoxy resin. In this case, it is impossible to reliably prevent the generation of bubbles due to heating and the generation of voids in the formed cured portion.

<Epoxy resin>
The epoxy resin composition of the present invention includes a liquid epoxy resin having two or more epoxy groups in the molecule. Such an epoxy resin is advantageous in increasing the reactivity of the curing reaction and the hardness after curing among various curable resins. Moreover, such an epoxy resin is an advantageous material from the viewpoints of heat resistance and dimensional accuracy of a cured product among various curable resins. Moreover, even if it does not contain a solvent etc., it can have moderate fluidity | liquidity as the whole epoxy resin composition. Further, such an epoxy resin has appropriate compatibility with the pregelling agent, so that viscosity stability at room temperature and thickening during gelation can be obtained.

  The epoxy resin is not particularly limited as long as it is liquid at room temperature (25 ° C.), and any known liquid epoxy resin can be used. Examples of the liquid epoxy resin include bisphenol type epoxy resins such as bisphenol A type epoxy resins and bisphenol F type epoxy resins; alicyclic epoxy resins; phenol novolac type epoxy resins and novolac type epoxy resins such as cresol novolac type epoxy resins. ; Triphenolalkane type epoxy resin such as triphenolmethane type epoxy resin and triphenolpropane type epoxy resin; Phenol aralkyl type epoxy resin, Biphenyl aralkyl type epoxy resin, Naphthalene type epoxy resin, Biphenyl type epoxy resin, Cyclopentadiene type epoxy resin Etc.

  Among these, it is preferable to include a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and an aminophenol epoxy resin. As a result, the viscosity stability at room temperature can be made particularly excellent, the permeability at the time of application of the epoxy resin composition can be made particularly excellent, and further, generation of voids due to gelation Can be prevented more reliably.

  When the epoxy resin composition contains bisphenol A type epoxy resin, bisphenol F type epoxy resin, and aminophenol epoxy resin, the content of bisphenol A type epoxy resin is 0.5 wt% or more and 4.0 wt%. It is preferable that the content of the bisphenol F type epoxy resin is 7.0 wt% or more and 40 wt% or less, and the content of the aminophenol epoxy resin is 10 wt% or more and 30 wt% or less. Thereby, the affinity between the epoxy resin and the pregelling agent described in detail later can be made particularly excellent, and the effect of including the pregelling agent is more remarkably exhibited. In addition, when the semiconductor chip (electronic component) or the circuit board is made of the material as described above, the wettability of the epoxy resin composition to these can be made particularly excellent, and voids are generated. Can be prevented more effectively.

  The content of the bisphenol A type epoxy resin in the epoxy resin composition is preferably 0.5% by weight or more and 4.0% by weight or less, but is 0.7% by weight or more and 3.5% by weight or less. Is more preferable, and it is further more preferable that it is 1.0 to 3.0 weight%. Thereby, the effects as described above are more remarkably exhibited.

  The content of the bisphenol F-type epoxy resin in the epoxy resin composition is preferably 7.0% by weight or more and 40% by weight or less, but more preferably 8.0% by weight or more and 35% by weight or less. It is preferably 10% by weight or more and 33% by weight or less. Thereby, the effects as described above are more remarkably exhibited.

  The content of aminophenol epoxy resin in the epoxy resin composition is preferably 10% by weight to 30% by weight, more preferably 13% by weight to 25% by weight, and more preferably 15% by weight. More preferably, the content is 22% by weight or less. Thereby, the effects as described above are more remarkably exhibited.

  The epoxy resin composition preferably contains 1,6-hexanediol epoxy resin in addition to bisphenol A type epoxy resin, bisphenol F type epoxy resin, and aminophenol epoxy resin. As a result, the affinity between the epoxy resin and the pregelling agent described in detail later can be further improved, and the effect of including the pregelling agent is more remarkably exhibited. In addition, when the semiconductor chip (electronic component) or the circuit board is composed of the materials described above, the wettability of the epoxy resin composition to these can be further improved, and voids are generated. Can be more effectively prevented.

  When the epoxy resin composition contains 1,6-hexanediol epoxy resin, the content of 1,6-hexanediol epoxy resin in the epoxy resin composition is 1.0 wt% or more and 6.0 wt% or less. It is preferably 1.5% by weight or more and 4.5% by weight or less, more preferably 2.0% by weight or more and 3.5% by weight or less. When the content of the 1,6-hexanediol epoxy resin is a value within the above range, the affinity between the epoxy resin and the pregelling agent described in detail later can be further improved. The effect by including is exhibited more notably. In addition, when the semiconductor chip (electronic component) or the circuit board is composed of the materials described above, the wettability of the epoxy resin composition to these can be further improved, and voids are generated. Can be more effectively prevented.

  The content of the epoxy resin in the epoxy resin composition is preferably 20% by weight to 60% by weight, more preferably 24% by weight to 55% by weight, and more preferably 29% by weight to 50% by weight. More preferably. Thereby, while allowing the functions of the epoxy resin to be exhibited more reliably, the functions of other components constituting the epoxy resin (for example, pregelling agent, curing agent, filler, etc.) can be exhibited more reliably, While preventing the generation of voids at the time of curing more effectively, the bondability (bonding strength) between the formed cured portion and the circuit board or electronic component can be made particularly excellent. Moreover, the fluidity | liquidity of an epoxy resin composition can be made suitable, and the ease of handling of an epoxy resin composition improves.

<Curing agent>
The epoxy resin composition of the present invention contains a curing agent. The curing agent has a function of accelerating the curing reaction of the epoxy resin in the epoxy resin composition of the present invention. When the epoxy resin composition does not contain a curing agent, the curing reaction of the epoxy resin by heating cannot be rapidly advanced.

  As the curing agent, various curing agents such as an acid anhydride, an amine curing agent, a phenol curing agent, and an imidazole curing agent can be used. In the present invention, a solid dispersion type amine adduct curing agent is used. Is preferred.

  In the present invention, the solid-dispersed amine adduct curing agent is a solid that is insoluble in an epoxy resin at room temperature (25 ° C.), and is a reaction product of an amine compound and an epoxy compound that is solubilized by heating and functions as a curing agent. It refers to things. In the epoxy resin composition of the present invention, such a solid dispersion-type amine adduct curing agent prevents the unintentional reaction of the epoxy resin during storage more reliably, and heats the epoxy resin by heating when necessary. The curing reaction can proceed efficiently. Moreover, the timing with which an epoxy resin hardens | cures and gelatinization of an epoxy resin composition at the time of heating an epoxy resin composition can be adjusted to a more suitable thing. Further, the hardness of the cured product can be made particularly excellent. Further, the storage stability as a one-pack type (non-mixed type) epoxy resin composition can be made particularly excellent, and the long-term storage in a state where each component is mixed can be made particularly excellent. it can.

  Examples of the epoxy compound used as a raw material for producing the solid dispersion type amine adduct curing agent include polyhydric phenols such as bisphenol A, bisphenol F, bisphenol AD, catechol and resorcinol, polyhydric alcohols such as glycerin and polyethylene glycol, and epichlorohydrin. Polyglycidyl ether obtained by reacting with glycidyl ether; glycidyl ether ester obtained by reacting hydroxycarboxylic acid such as p-hydroxybenzoic acid and β-hydroxynaphthoic acid with epichlorohydrin; phthalic acid, terephthalic acid, etc. Polyglycidyl ester obtained by reacting polycarboxylic acid with epichlorohydrin, etc .; 4,4'-diaminodiphenylmethane, m-aminophenol and the like Glycidylamine compounds obtained by reacting with hydrin, etc., as well as polyfunctional epoxy compounds such as epoxidized phenol novolac resin, epoxidized cresol novolac resin, epoxidized polyolefin, butyl glycidyl ether, phenyl glycidyl ether, glycidyl And monofunctional epoxy compounds such as methacrylate.

The amine compound used as a raw material for producing the solid dispersion type amine adduct curing agent is an amino group (—NH ₂ ) that can undergo an addition reaction with an epoxy group, or one or two of the active hydrogens that the amino group has are alkyl groups. It may be a compound having a functional group substituted with, for example, a primary amine, a secondary amine, or a tertiary amine. Examples of such amine compounds include aliphatic amines such as diethylenetriamine, triethylenetetramine, n-propylamine, 2-hydroxyethylaminopropylamine, cyclohexylamine, and 4,4′-diamino-dicyclohexylmethane; Aromatic amine compounds such as 4'-diaminodiphenylmethane and 2-methylaniline, 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazoline, 2,4-dimethylimidazoline, piperidine, piperazine And nitrogen-containing heterocyclic compounds such as The amine compound as a raw material for producing the solid dispersion type amine adduct curing agent includes a urea compound (compound having a partial structure of NC (= O) N).

  Among amine compounds, tertiary amine is a raw material that gives a solid dispersion type amine adduct curing agent having particularly excellent curing acceleration. Examples of such compounds include amines such as dimethylaminopropylamine, diethylaminopropylamine, di-n-propylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, N-methylpiperazine and the like. Primary amine structure (amino group) with tertiary amine structure in the molecule such as compounds and imidazole compounds such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, etc. Or a secondary amine structure (tertiary amine, 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2-dimethylaminoethanol, 2-diethylaminoethanol, 1 Butoxymethyl-2-dimethylaminoethanol, 1- (2-hydroxy-3-phenoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-ethyl-4-methylimidazole, 1 -(2-hydroxy-3-butoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-butoxypropyl) -2-ethyl-4-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) ) -2-Phenylimidazoline, 1- (2-hydroxy-3-butoxypropyl) -2-methylimidazoline, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol, N- β-hydroxyethylformoline, 2-dimethylaminoethanethiol, 2- Mercaptopyridine, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 4-mercaptopyridine, N, N-dimethylaminobenzoic acid, N, N-dimethylglycine, nicotinic acid, isonicotinic acid, picolinic acid, N, N- Alcohols having a tertiary amine in the molecule, such as dimethylglycine hydrazide, N, N-dimethylpropionic hydrazide, nicotinic hydrazide, isonicotinic hydrazide, phenols, thiols, carboxylic acids, hydrazides, etc. Can be mentioned.

  Moreover, as a solid dispersion type amine adduct type hardening | curing agent, what processed the surface of the reaction product of an amine compound and an epoxy compound as mentioned above with an isocyanate compound or an acidic compound etc. may be used, for example.

  Among the solid dispersion type amine adduct type curing agents, those commercially available include, for example, “Fujicure FXR1081” (trade name of T & K Toka Co., Ltd.), “Amicure PN-23” (trade name of Ajinomoto Co., Inc.). ), "Amicure PN-H" (Ajinomoto Co., Ltd. trade name), "Amicure MY-24" (Ajinomoto Co., Ltd. trade name), "Hardener X-3661S" (A-C.R. Trade name) , “Hardener X-3670S” (trade name, ARC Corporation), “Novacure HX-3742” (trade name, Asahi Kasei Co., Ltd.), “Novacure HXA-3922HP” (trade name, Asahi Kasei Co., Ltd.), etc. Is mentioned.

  The content of the curing agent in the epoxy resin composition is preferably 3% to 30% by weight, more preferably 8% to 25% by weight, and more preferably 10% to 20% by weight. More preferably. As a result, the other components (for example, epoxy resin, pregelling) constituting the epoxy resin composition can be achieved while ensuring the functions of the above-described curing agent (in particular, the solid dispersion type amine adduct curing agent). The bonding function (bonding strength) of the cured part to be formed with the circuit board and electronic components while more effectively preventing the generation of voids during curing. It can be made particularly excellent. In addition, when using in combination of 2 or more types as a hardening | curing agent, the sum of the content rate of these components shall be employ | adopted as a content rate of a hardening | curing agent.

  The content of the curing agent with respect to 100 parts by weight of epoxy resin is preferably 10 parts by weight or more and 100 parts by weight or less, more preferably 15 parts by weight or more and 70 parts by weight or less, and more preferably 20 parts by weight or more and 60 parts by weight or less. More preferably, it is no more than parts by weight. As a result, the other components (for example, epoxy resin, pregelling) constituting the epoxy resin composition can be achieved while ensuring the functions of the above-described curing agent (in particular, the solid dispersion type amine adduct curing agent). The bonding function (bonding strength) of the cured part to be formed with the circuit board and electronic components while more effectively preventing the generation of voids during curing. It can be made particularly excellent.

<Filler>
The epoxy resin composition of the present invention contains an inorganic filler. By including the inorganic filler, the coefficient of thermal expansion of the cured portion formed using the epoxy resin composition of the present invention can be more effectively reduced. As a result, in the manufactured semiconductor device, the connection reliability between the electronic component and the circuit board can be increased.

  Examples of the inorganic filler include inorganic fillers such as silica, alumina, aluminum nitride, boron nitride, silicon nitride, silicon carbide, and calcium carbonate. In particular, when silica is used as the inorganic filler, the coefficient of thermal expansion is smaller than that of other fillers, and the coefficient of thermal expansion of the formed cured portion can be more effectively reduced. As a result, in the manufactured semiconductor device, the connection reliability between the electronic component and the circuit board can be made particularly high.

  The shape of the inorganic filler is not particularly limited, but is preferably spherical. Thereby, even if it is a case where the content rate of an inorganic filler is made into a comparatively high thing, the viscosity increase of an epoxy resin composition can be suppressed effectively.

  When spherical silica is used as the inorganic filler, the maximum particle size is preferably 0.1 μm or more and 10 μm or less. Thereby, the thermal expansion coefficient of the hardening part formed can be reduced further effectively. As a result, in the manufactured semiconductor device, the connection reliability between the electronic component and the circuit board can be further increased.

  The content of the inorganic filler in the epoxy resin composition is preferably 15% by weight to 70% by weight, more preferably 20% by weight to 66% by weight, and more preferably 25% by weight to 55% by weight. More preferably, it is as follows. As a result, the functions of the other components (for example, epoxy resin, curing agent, pregelling agent, etc.) constituting the epoxy resin composition are more reliably achieved while the functions of the inorganic filler as described above are more reliably exhibited. It is possible to make it particularly effective in improving the bondability (bonding strength) of the formed hardened part to the circuit board and electronic components while more effectively preventing the generation of voids during hardening. it can.

<Pregelling agent>
The epoxy resin composition of the present invention contains a pregelator composed of a vinyl polymer at a predetermined content. The pregelling agent is a component that gels the epoxy resin composition by heating.

  In particular, in the present invention, the pregelling agent gels the epoxy resin composition before the epoxy resin is cured when the epoxy resin composition is heated at 190 ° C.

  By including such a pregelling agent at a predetermined content, the epoxy resin composition can be smoothly applied to the circuit board, and in the press-contacting process, it is formed while preventing generation of voids. Therefore, it is possible to improve the bonding strength of the hardened portion to the circuit board and the electronic component, and to improve the reliability of the manufactured semiconductor device.

This is considered to be due to the following reasons.
That is, first, since the gelation of the epoxy resin composition does not proceed at the time of supply to the circuit board, the epoxy resin composition has sufficient fluidity and smoothly performs the epoxy resin composition application step. Therefore, the epoxy resin composition can surely enter into a narrow space such as the periphery of the electronic component.

  On the other hand, in the pressure welding process, the temperature of the epoxy resin composition applied on the circuit board rises due to heat conduction. By satisfying the above relationship, the temperature of the epoxy resin composition is increased. The epoxy resin composition gels before reaching the curing start temperature. For this reason, when hardening of an epoxy resin advances, it has already been in the state (high viscosity state) where the stability of the shape of the epoxy resin composition increased.

  By the way, circuit boards, electronic parts, and epoxy resin compositions usually contain substances having a relatively low boiling point by absorbing moisture contained in the atmosphere, and such low-boiling substances. It is considered that (mainly water) vaporizes during heating, which contributes to the generation of voids. The curing of the epoxy resin usually proceeds at a temperature higher than the boiling point of the low boiling point substance as described above.

  For this reason, when the curing of the epoxy resin proceeds in a state where the viscosity of the epoxy resin composition is low, the gas generated from the circuit board or the like is taken into the epoxy resin composition in the low viscosity state, and as a result, voids are generated. However, in the present invention, when the curing of the epoxy resin proceeds, since the stability of the shape of the epoxy resin composition has already been increased (high viscosity state), it is generated from a circuit board or the like. The gas is effectively prevented from being taken into the epoxy resin composition (cured part), and as a result, the generation of voids is effectively prevented.

  In addition, the epoxy resin composition has sufficient fluidity when supplied to the circuit board and in contact with the electronic component, and is sufficiently wetted on the surface of the circuit board and electronic component. In a state where the gelation of the epoxy resin composition has progressed and the curing of the epoxy resin has not progressed, that is, in a state where the fluidity has decreased, the epoxy resin composition is in close contact with the circuit board and the electronic component. Is maintained. For this reason, instead of using a flowable epoxy resin composition, the present invention is superior in bonding strength to the circuit board or electronic component of the cured portion to be formed in comparison with the case where a sheet material is used. be able to.

  Hereinafter, the state change of the epoxy resin composition in the press-contacting process will be described with reference to FIG.

  First, in the low temperature region before heating, the viscosity of the epoxy resin composition is sufficiently low. For this reason, the epoxy resin composition can be smoothly applied to the circuit board, and the epoxy resin composition can surely enter into a narrow space such as the periphery of the electronic component.

  In the initial stage of heating, that is, the stage corresponding to the initial stage of heat transfer for heating by the bonding tool, the temperature of the epoxy resin composition increases, and accordingly, the viscosity of the epoxy resin composition decreases. As a result, even if there is a portion where the epoxy resin composition is not sufficiently wetted on the circuit board or the electronic component, it is sufficiently wetted at this stage.

  Thereafter, when the temperature of the epoxy resin composition further increases, gelation of the epoxy resin composition proceeds, and the viscosity of the epoxy resin composition starts to increase.

  When the temperature of the epoxy resin composition continues to rise, gelation of the epoxy resin composition is completed, and the viscosity of the epoxy resin composition is stabilized (flattened on the graph).

Furthermore, when the temperature of the epoxy resin composition increases, the curing reaction of the epoxy resin proceeds, and the viscosity of the epoxy resin composition increases accordingly. At this time, the circuit board or the like is also at a high temperature, and the vaporization of the low boiling point compound is likely to proceed. As described above, the gelation of the epoxy resin composition is completed, and the epoxy resin composition Since the viscosity of this is sufficiently high, generation of voids is reliably prevented. In addition, since the curing of the epoxy resin does not progress during gelation, it does not hinder the bump connection by pressurization. If the heating continues thereafter, the curing reaction of the epoxy resin is completed, resulting in a cured part that has lost its fluidity. .

  In the present invention, the relationship between the gelation timing of the epoxy resin composition and the cure timing of the epoxy resin is defined as a relationship when the heating temperature is 190 ° C., but a temperature of 190 ° C. is adopted. This is because the heating performed in the pressure welding process is generally performed at a temperature of about 190 ° C., and at 190 ° C., if the above-described relationship is satisfied, the heating is generally performed in the pressure welding process. This is because it has been confirmed that the above-described effects can be obtained even in the heating temperature range.

  The excellent effects as described above are obtained by including a predetermined amount of the pregelling agent as described above, and when the pregelling agent as described above is not included, Even if it is included, if the content is too small, the excellent effects as described above cannot be obtained.

  The content of the pregelling agent in the epoxy resin composition may be 2.0% by weight or more and 20% by weight or less, preferably 2.5% by weight or more and 15% by weight or less, and 3.0% by weight. It is more preferable that the content is not less than 10% and not more than 10% by weight. Thereby, the effects as described above are more remarkably exhibited.

  Further, the content of the pregelling agent with respect to 100 parts by weight of the epoxy resin is preferably 5 parts by weight or more and 65 parts by weight or less, more preferably 7 parts by weight or more and 45 parts by weight or less, and more preferably 10 parts by weight or more. More preferably, it is 30 parts by weight or less. Thereby, the effect of this invention by containing the predetermined pregelling agent as mentioned above is exhibited more notably.

  The pregelling agent is composed of a vinyl polymer and may satisfy the above-mentioned relationship, but preferably satisfies the following conditions.

  That is, the pregelling agent preferably has an acetone-soluble weight average molecular weight of 100,000 or more and 20 million or less, more preferably 200,000 or more and 10 million or less, and 300,000 or more and 500,000 or less. More preferably, it should be 10,000 or less. As a result, high gelling properties can be expressed even with a relatively small content, and the stability of the shape of the epoxy resin composition after gelation can be made particularly excellent and dissolved in the epoxy resin. It is possible to achieve a sufficient gel state in a short time.

In the present specification, the acetone-soluble component means the dissolved weight (%) after a predetermined amount of pregelling agent is dissolved in 50 times the weight of acetone and refluxed at 70 ° C. for 6 hours. . More specifically, it refers to the required value. Specifically, 1 g of pregelling agent was dissolved in 50 g of acetone, refluxed and extracted at 70 ° C. for 6 hours, and then centrifuged at 4 ° C. using a centrifuge (for example, “CRG SERIES” manufactured by Hitachi, Ltd.). Centrifuge at 14,000 rpm for 30 minutes, then remove the separated acetone-soluble matter by decantation, and dry the acetone-insoluble matter in a vacuum dryer at 50 ° C. for 24 hours to measure the weight. The dissolved content (% by weight) can be calculated by the following formula.
(Acetone soluble matter) = (Weight of 1-acetone insoluble matter) × 100

  The acetone-soluble content of the pregelling agent is preferably 2.0% by weight or more and 35% by weight or less, more preferably 5.0% by weight or more and 30% by weight or less, and 8.0% by weight or more and 25% by weight or less. More preferably, it is not more than% by weight. This makes it possible to more effectively suppress a decrease in the glass transition temperature of a cured product obtained by curing the epoxy resin composition, while making the gelation characteristics during heating sufficiently excellent. The reliability of the obtained semiconductor device can be made particularly excellent.

  The acetone-soluble component can be appropriately adjusted by adjusting the content of the crosslinkable monomer in the monomer raw material. In order to increase the acetone-soluble content, the content of the crosslinkable monomer is decreased. To decrease the acetone-soluble content, the content of the crosslinkable monomer may be increased.

  The glass transition temperature of the pregelling agent is preferably 0 ° C. or higher and 250 ° C. or lower. As a result, even when the pregelling agent in the epoxy resin composition is relatively high, a decrease in the glass transition temperature of the cured product obtained by curing the epoxy resin composition can be suppressed, and gelation can be efficiently performed at a constant temperature. Can be in a state.

In the present specification, the glass transition temperature can be determined by the Fox equation. When the pregelling agent is a homopolymer, standard analytical values described in the “Polymer Data Handbook” edited by the Polymer Science Society can be adopted. It can be calculated by the formula (1) from the glass transition temperature (Tg) of the unit homopolymer.
The Fox formula is shown below.
1 / (273 + Tg) = Σ (wi / (273 + Tgi)) Equation (1)

  In the formula, Tg is Tg (° C.) of the copolymer, wi is a weight fraction of the monomer i, and Tgi is Tg (° C.) of a homopolymer obtained by polymerizing the monomer i.

  The pregelling agent is composed of a vinyl polymer. Thereby, when the semiconductor chip (electronic component) or the circuit board is composed of the material as described above, the affinity of the epoxy resin composition for these can be adjusted to a suitable one, and the epoxy resin The wettability of the composition can be made particularly excellent. As a result, generation of voids can be more effectively prevented.

  As the vinyl monomer component constituting the pregelator, those capable of radical polymerization can be suitably used. Specific examples of the vinyl monomer component constituting the pregelator include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meta ) Acrylate, t-butyl (meth) acrylate, i-butyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (Meth) acrylate, phenyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate Relate, tricyclo [5.2.1.02.6] decan-8-yl-methacrylate, dicyclopentadienyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N-methyl-2, (Meth) acrylates such as 2,6,6-tetramethylpiperidyl (meth) acrylate; vinyl cyanide monomers such as (meth) acrylonitrile; aromatic vinyl monomers such as styrene, α-methylstyrene and vinyltoluene Acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, fumaric acid, isocrotonic acid, salicylic acid vinyloxyacetic acid, allyloxyacetic acid, 2- (meth) acryloylpropanoic acid, 3- (meth) acryloylbutanoic acid, 4-vinyl Carboxyl group-containing vinyl monomers such as benzoic acid; hydroxymethyl (meth) acrylic Hydroxyl-containing vinyl monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and glycerol mono (meth) acrylate Glycidyl group-containing vinyl monomers such as glycidyl (meth) acrylate; (meth) acrylamide; vinyl monomers such as vinyl pyridine, vinyl alcohol, vinyl imidazole, vinyl pyrrolidone, vinyl acetate, 1-vinyl imidazole; monomethyl Itaconic acid esters such as itaconate, monoethyl itaconate, monopropyl itaconate, monobutyl itaconate, dimethyl itaconate, diethyl itaconate, dipropyl itaconate, dibutyl itaconate; Fumaric acid esters such as methyl fumarate, monoethyl fumarate, monopropyl fumarate, monobutyl fumarate, dimethyl fumarate, diethyl fumarate, dipropyl fumarate, dibutyl fumarate; and monomethyl malate, monoethyl maleate , Maleic acid esters such as monopropylmalate, monobutylmalate, dimethylmalate, diethylmalate, dipropylmalate, dibutylmalate, etc., and combinations of one or more selected from these Can be used.

  Among them, the pregelling agent preferably contains, as monomer components, methyl methacrylate: 70% by weight to 99% by weight and vinyl monomers other than methyl methacrylate: 1% by weight to 30% by weight. Thereby, the affinity of an epoxy resin and a pregelling agent can be made especially excellent, and the effect by including a pregelling agent is exhibited more notably. In addition, when the semiconductor chip (electronic component) or the circuit board is made of the material as described above, the affinity of the epoxy resin composition for these can be adjusted to a more suitable one, and the epoxy resin The wettability of the composition can be made particularly excellent. As a result, generation of voids can be more effectively prevented.

  Further, the vinyl monomer other than methyl methacrylate is one or more selected from the group consisting of a carboxyl group-containing vinyl monomer, a hydroxyl group-containing vinyl monomer, and a glycidyl group-containing vinyl monomer. It is preferable that it contains a functional group-containing monomer. Thereby, the affinity of an epoxy resin and a pregelling agent can be made further excellent, and the effect by including a pregelling agent is exhibited more notably. In addition, when the semiconductor chip (electronic component) or the circuit board is composed of the materials as described above, the affinity of the epoxy resin composition for these can be adjusted to a more suitable one, and the epoxy resin The wettability of the composition can be further improved. As a result, the generation of voids can be more effectively prevented. However, even when the pregelling agent includes a glycidyl group-containing vinyl monomer as a monomer component, the pregelling agent does not have two or more glycidyl groups in the molecule.

  The content of the functional group-containing monomer in the vinyl polymer (pregelling agent) (content in terms of monomer raw material) is preferably 2% by weight or more and 30% by weight or less, preferably 4% by weight. % To 20% by weight is more preferable. Thereby, the effects as described above are more remarkably exhibited.

Examples of the carboxyl group-containing vinyl monomer include methacrylic acid.
Examples of the hydroxyl group-containing vinyl monomer include 2-hydroxyethyl methacrylate.

  Examples of the glycidyl group-containing vinyl monomer include glycidyl methacrylate.

<Coupling agent>
The epoxy resin composition of the present invention may contain a coupling agent. By including the coupling agent, it is possible to further improve the adhesion between the cured product of the epoxy resin composition and the circuit board or electronic component.

  Examples of the coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, vinyltrimethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyltrimethoxysilane, 3- Examples include acryloxypropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, bis (triethoxysilylpropyl) tetrasulfide, and 3-isocyanatopropyltriethoxysilane. Among these, 3-glycidoxypropyltrimethoxysilane and 3-aminopropyltrimethoxysilane are preferable from the viewpoint of adhesion. Examples of commercially available products include KBM403, KBE903, and KBE9103 manufactured by Shin-Etsu Chemical.

  The content of the coupling agent in the epoxy resin composition is preferably 0.01 wt% or more and 1.0 wt% or less, more preferably 0.05 wt% or more and 0.7 wt% or less. 0.07 wt% or more and 0.50 wt% or less is more preferable. As a result, the functions of the other components (for example, epoxy resin, pregelling agent, inorganic filler, etc.) constituting the epoxy resin composition are more exhibited while ensuring the functions of the coupling agent as described above. It should be able to be demonstrated reliably, and the bondability (bonding strength) with the circuit board and electronic parts of the hardened part to be formed should be particularly excellent while preventing the generation of voids during curing more effectively. Can do. In addition, when using in combination of 2 or more types of components as a coupling agent, the sum of the content rate of these components shall be employ | adopted as a content rate of a hardening | curing agent.

<Other ingredients>
The epoxy resin composition of the present invention may contain components other than the above (other components). Examples of such components include resin components other than the epoxy resins described above (for example, resins having only one epoxy group in the molecule), thiol compounds having mercapto groups in the molecule, boric acid esters, and aggregation prevention. Agents, surfactants, various polymerization accelerators, luminescent materials, colorants, antifoaming agents, leveling agents, thixotropic agents, stress relaxation agents, ion catchers and the like. From the viewpoint of suppressing voids, it is preferable not to include an organic solvent, particularly a low boiling point organic solvent.

  The content of other components in the epoxy resin composition is preferably 10% by weight or less, and more preferably 3% by weight or less. In addition, when using in combination of 2 or more types of components as another component, the sum of the content rate of these components shall be employ | adopted as the content rate of other components.

  The viscosity of the epoxy resin composition at 25 ° C. (viscosity measured using a cone plate viscometer) is preferably 1 Pa · s to 50 Pa · s, and preferably 5 Pa · s to 20 Pa · s. Is more preferable. When the viscosity of the epoxy resin composition is a value within the above range, the epoxy resin composition can be smoothly applied to the circuit board, and voids due to air entrainment can be more effectively prevented. be able to. In addition, the epoxy resin composition can surely enter into a narrow space such as the periphery of the electronic component. The viscosity of the epoxy resin composition can be measured using, for example, a cone plate viscometer.

  The gelation temperature of the epoxy resin composition is preferably 70 ° C. or higher and 99 ° C. or lower, more preferably 74 ° C. or higher and 97 ° C. or lower, and further preferably 75 ° C. or higher and 95 ° C. or lower. Thereby, the effects as described above can be more remarkably exhibited. The gelation temperature can be determined as follows. That is, using a cone plate type viscosity measuring device (for example, HAAKE Roto Visco-1 manufactured by Thermo Co., Ltd.), parallel plate diameter: 20 mm, gap: 0.3 mm, frequency: 1 Hz, start temperature: 25 ° C., heating rate : The temperature dependence of the viscoelasticity of the epoxy resin composition is measured under the condition of 10 ° C./min, and the temperature at which thickening starts can be defined as the gelation temperature.

  The curing start temperature of the epoxy resin composition is preferably 100 ° C. or higher and 200 ° C. or lower, more preferably 102 ° C. or higher and 125 ° C. or lower, and still more preferably 104 ° C. or higher and 120 ° C. or lower. In the present invention, the curing start temperature of the epoxy resin composition refers to a starting temperature: 25 ° C. and a heating rate: 10 ° C./min with a differential thermal analyzer (for example, DTG-60 manufactured by Shimadzu Corporation). The temperature at which the reaction heat is measured under conditions and the reaction heat is increased.

  The difference between the curing start temperature of the epoxy resin composition and the gelation temperature of the epoxy resin composition is preferably 10 ° C. or more and 40 ° C. or less, more preferably 15 ° C. or more and 32 ° C. or less, It is more preferable that the temperature is not lower than 26 ° C. As a result, the effects as described above can be exhibited more remarkably.

  The epoxy resin composition preferably satisfies the following conditions. That is, when 5 mg of the epoxy resin composition is heated at 190 ° C., the heating time until the degree of cure reaches 95% is preferably 2 seconds to 10 seconds, and preferably 3 seconds to 8 seconds. Is more preferable. Thereby, in the manufacture of the semiconductor device, the bonding strength between the hardened portion, the circuit board, and the electronic component can be made particularly excellent while performing the pressure welding process in a shorter time. Accordingly, the reliability of the manufactured semiconductor device can be made particularly high while making the productivity of the semiconductor device particularly excellent.

  The degree of cure can be measured using various devices such as a differential thermal analyzer (manufactured by Shimadzu Corp.) and a differential scanning thermal analyzer (manufactured by SI Corp.).

  The epoxy resin composition has a viscosity at 25 ° C. of 20 Pa · s or less, and it is preferable that the time until gelation starts when heated at 190 ° C. is within 5 seconds. As a result, it is possible to more effectively prevent void entrainment while more effectively suppressing the generation of voids due to volatile components.

  A cured product obtained by curing the epoxy resin composition of the present invention has a high glass transition temperature and a low thermal expansion coefficient. For this reason, it is possible to more effectively prevent the occurrence of problems such as a decrease in the adhesion of the hardened part to the electronic components and the circuit board or a crack in the hardened part due to the heat history during or after the manufacture of the semiconductor device. be able to.

  The glass transition temperature of the cured product of the epoxy resin composition of the present invention is preferably 100 ° C. or higher, and more preferably 130 ° C. or higher.

  The linear expansion coefficient in the range of 25 ° C. to 100 ° C. of the cured product of the epoxy resin composition of the present invention is preferably 50 ppm / ° C. or less, and more preferably 40 ppm / ° C. or less. Thereby, the effects as described above are more remarkably exhibited.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to these.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

[1] Production of epoxy resin composition (Example 1)
Bisphenol A type epoxy resin (850 LVP, manufactured by DIC Corporation): 2.0 parts by weight, Bisphenol F type epoxy resin (830 LVP, manufactured by DIC Corporation): 13 parts by weight, and aminophenol epoxy resin (630 LSD) , Manufactured by Mitsubishi Chemical Corporation): 20 parts by weight, solid dispersion type amine adduct curing agent (HXA-3922HP, manufactured by Asahi Kasei E-Materials Co., Ltd.): 15 parts by weight, spherical silica filler (MP- 15EF, manufactured by Tatsumori Co., Ltd., maximum particle size: 5 μm): 50 parts by weight, KBM-403 as a coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.): 0.1 part by weight, pregelling agent Pregelling agent A as: 4.0 parts by weight was mixed, uniformly dispersed with a three-roll mill, added and stirred under reduced pressure to produce an epoxy resin composition.
In addition, as the pregelling agent A, what was prepared as follows was used.

  In a separable flask equipped with a Max blend stirrer, reflux condenser, temperature controller, dropping pump and nitrogen inlet tube, ion-exchanged water: 78.00 parts by weight, methyl methacrylate: 2.83 parts by weight and n-butyl methacrylate: 2 .17 parts by weight were added, and nitrogen gas was bubbled for 30 minutes while stirring at 120 rpm.

  Thereafter, the temperature was raised to 80 ° C. in a nitrogen atmosphere, and an aqueous solution of ammonium persulfate: 0.02 parts by weight and ion-exchanged water: 2.00 parts by weight prepared in advance was added and held for 60 minutes to form seed particles. I let you.

  In the flask in which the seed particles were formed, methyl methacrylate: 92.94 parts by weight, n-butyl methacrylate: 2.00 parts by weight, allyl methacrylate: 0.06 parts by weight, ammonium di-2-ethylhexyl sulfosuccinate: 1 0.000 part by weight, 2,2′-azobis (2,4-dimethylvaleronitrile): 0.02 part by weight and 50.00 parts by weight of ion-exchanged water were mixed with a homogenizer (manufactured by IKA, “Ultra Turrax T- 25 ”, 25000 rpm), the mixture obtained by emulsification was added dropwise over 300 minutes, and then held for 1 hour to complete the polymerization.

  The obtained vinyl polymer emulsion was spray-dried using an L-8i type spray dryer manufactured by Okawara Chemical Industries Co., Ltd. to obtain a pregelator A as a vinyl polymer powder.

  The glass transition temperature of the pregelling agent A is 100 ° C., the average particle size of the pregelling agent A is 0.63 μm, the weight-average molecular weight of the acetone-soluble component for the pregelling agent A is 460,000, and the acetone for the pregelling agent A The weight ratio of the soluble component was 10% by weight.

(Examples 2 to 6)
An epoxy resin composition was produced in the same manner as in Example 1 except that the components used as raw materials and the amounts used thereof were as shown in Table 1.

(Comparative Example 1)
An epoxy resin composition was produced in the same manner as in Example 1 except that the pregelling agent was not used as a raw material and the amounts of each component used were as shown in Table 1.

(Comparative Example 2)
An epoxy resin composition was produced in the same manner as in Example 2 except that the pregelling agent was not used as a raw material, and the amounts of each component used were as shown in Table 1.

(Comparative Examples 3 and 4)
An epoxy resin composition was produced in the same manner as in Example 1 except that the amounts of components used as raw materials were as shown in Table 1.

(Comparative Example 5)
As the curing agent, 2MA-OK-PW (manufactured by Shikoku Kasei Co., Ltd.) as a curing agent other than the solid dispersion type amine adduct curing agent is used in place of the solid dispersion type amine adduct curing agent, and pregelling is performed. An epoxy resin composition was produced in the same manner as in Comparative Example 4 except that the content of the agent was changed.

(Comparative Example 6)
An epoxy resin composition was produced in the same manner as in Example 1 except that Zefiac F351 (manufactured by Aika Industry Co., Ltd.) was used as the pregelling agent.

Table 1 summarizes the compositions of the epoxy resin compositions of the above Examples and Comparative Examples. In the table, bisphenol A type epoxy resin (850 LVP, manufactured by DIC Corporation) is “ERA”, bisphenol F type epoxy resin (830 LVP, manufactured by DIC Corporation) is “ERF”, aminophenol epoxy resin ( 630LSD, manufactured by Mitsubishi Chemical Co., Ltd.) "ERAP", 1,6-hexanediol epoxy resin (YED216D, manufactured by Mitsubishi Chemical Corporation) "ERHD", solid dispersion type amine adduct curing agent (HXA- 3922HP, manufactured by Asahi Kasei E-Materials Co., Ltd.) “EHA”, 2MA-OK-PW (manufactured by Shikoku Kasei Co., Ltd.) as a curing agent other than the solid dispersion type amine adduct curing agent “EHB”, Spherical silica filler (MP-15EF, manufactured by Tatsumori Co., Ltd., maximum particle size: 5 μm) KBM-403 (“FEF” coupling agent) “KAE” for Koe Chemical Co., Ltd., “PGA” for pregelling agent A as a pregelling agent, and “PGF” for Zefiac F351 (manufactured by Aika Industries) as a pregelling agent. .
Table 1 also shows the viscosity value at 25 ° C. of the epoxy resin composition measured using a cone plate viscometer (manufactured by Themo).

[2] Evaluation of Epoxy Resin Composition [2.1] Relationship Between Gelation Timing and Curing Timing For each of the epoxy resin compositions of the above Examples and Comparative Examples, 10 mg and a surface temperature of 190 ° C., respectively. It was placed on the set ASONE hot plate (DP-1S) and stirred with a stir bar so as to draw a circle. The color tone of the epoxy resin composition did not change, but the fluidity was impaired and changed to a high viscosity state. The state was gelled, and the color tone of the epoxy resin composition was changed from white to brown and solidified without any fluidity. The case where the epoxy resin composition was gelled before the epoxy resin was cured was designated as “◯”, and the case where the epoxy resin composition was not gelled before the epoxy resin was cured was designated as “x”.

[2.2] Gelation temperature For the epoxy resin compositions of the above Examples and Comparative Examples, a cone plate type viscosity measuring device (HAAKE Roto Visco-1 manufactured by Thermo Co., Ltd.) was used, and parallel plate diameter: 20 mm. , Gap: 0.3 mm, frequency: 1 Hz, start temperature: 25 ° C., temperature increase rate: 10 ° C./minute, the temperature dependence of the viscoelasticity of the epoxy resin composition is measured, and the temperature at which thickening starts Was determined as the gelation temperature.

[2.3] Curing start temperature With respect to the epoxy resin compositions of the above examples and comparative examples, a starting temperature: 25 ° C. and a heating rate: 10 ° C. using a differential thermal analyzer (DTG-60, manufactured by Shimadzu Corporation). The temperature dependence of the reaction heat was measured under the conditions of / min, and the temperature at which the reaction heat increased was determined as the curing start temperature.

[2.4] Time to Reach Predetermined Curing Degree First, 5 mg of each of the epoxy resin compositions of the above Examples and Comparative Examples was applied to a thermal analysis clamp cell (material aluminum, 5 mmφ).

  Next, the clamp cell to which the epoxy resin composition was applied was previously placed on a hot plate (DP-1S) manufactured by AS ONE with a surface temperature set at 190 ° C., and the degree of cure of the fat composition was 95%. The heating time to reach was determined. A differential thermal analyzer (manufactured by Shimadzu Corporation, manufactured by DTG-60) was used for the measurement of the degree of curing.

[2.5] Storage Stability The epoxy resin compositions of the above Examples and Comparative Examples were allowed to stand for 5 days in an environment of temperature: 25 ° C. and humidity: 50% RH.

  Then, about each epoxy resin composition, the viscosity in 25 degreeC was measured using the cone-plate-type viscosity measuring apparatus (Thermo Co., Ltd. product HAAKE Roto Visco-1), and the viscosity from the viscosity immediately after manufacture (25 degreeC) The amount of change was determined and evaluated according to the following criteria. It can be said that the smaller the amount of change in viscosity, the better the storage stability.

A: The amount of change in viscosity is less than 25% of the initial value.
B: The amount of change in viscosity is 25% or more and less than 100% of the initial value.
C: The amount of change in viscosity is 100% or more of the initial value.

[2.6] Permeability (fillability)
About the epoxy resin composition of each said Example and a comparative example, the permeability was evaluated with the following method.

  Masking of 20 μm was provided on both sides of the cover glass (22 × 22 × 0.1 mm thickness), and the same size cover glass was shifted by 2 mm and fixed. 100 mg of the epoxy resin composition was applied to the shifted position, placed on a hot plate (DP-1S) manufactured by AS ONE with a surface temperature set at 190 ° C., the penetration distance was measured, and evaluated according to the following criteria.

A: The penetration distance is less than 5 mm.
B: The penetration distance is 5 mm or more and less than 10 mm.
C: The penetration distance is 10 mm or more.

[3.1] Glass transition temperature Using each of the epoxy resin compositions of the above Examples and Comparative Examples, after heat treatment at 190 ° C. for 5 minutes, the heat treatment at 150 ° C. for 60 minutes is performed to obtain an epoxy resin composition. The product was cured to obtain a cured product. The obtained cured product was cut out at 5 mm × 50 mm × thickness 1 mm, DMA measurement was performed from room temperature to 200 ° C. using EXSTAR-600 manufactured by SII, and the maximum value of loss elasticity was obtained.

[3.2] Coefficient of linear expansion Using the epoxy resin compositions of the above examples and comparative examples, after heat treatment at 190 ° C. for 5 minutes, respectively, heat treatment at 150 ° C. for 60 minutes to obtain an epoxy resin composition The product was cured to obtain a cured product. The obtained cured product was cut out at 5 mm × 50 mm × thickness 1 mm and measured from room temperature to 200 ° C. with an XSTAR-600 manufactured by SII, and the coefficient of thermal expansion from 40 ° C. to 80 ° C. was measured.

[4] Manufacture of Semiconductor Device Using the epoxy resin compositions of the examples and comparative examples, semiconductor devices were manufactured as follows.

First, about 10 mg of the above resin composition B is placed at the center of the electronic component mounting position on a printed wiring board (0.1 mm thick glass epoxy board FR-4, copper foil thickness 18 μm) with Au / Ni plating on the electrode surface. Applied. Next, a 10 mm × 10 mm × 0.3 mm silicon chip (gold stud bump size 50 μm × 50 μm × 25 μm, number of bumps: 200, bump pitch: 120 μm to 120 μm) 200 μm) was bonded together by heating and pressing for 5 seconds under the conditions of 190 ° C. and 15 kg / cm ² using a bonding apparatus, to obtain a semiconductor device as a sample for characteristic evaluation.

[5.1] Situation of generation of voids For the semiconductor device obtained in [4] above, the void area ratio of the cured interior was measured using an ultrasonic microscope manufactured by Hitachi Construction Machinery Finetech Co., and the following criteria were used. evaluated.

A: Generation of voids is not recognized at all.
B: The total area of all voids is less than 1% with respect to the area of the semiconductor element.
C: The total area of all voids is 1% or more with respect to the area of the semiconductor element.

[5.2] Initial Bondability For each of the 20 semiconductor devices obtained in [4] above, a digital multimeter probe is applied to the measurement terminals formed on the conductor wiring of the circuit board, and the electrical operation is confirmed. The initial connectivity was evaluated. And about each said Example and the comparative example, initial stage connectivity was evaluated by the number of what the disconnection defect generate | occur | produced among each 20 semiconductor devices.
These results are summarized in Table 2.

  As is clear from Table 2, excellent results were obtained in the present invention. On the other hand, in the comparative example, a satisfactory result was not obtained. The epoxy resin compositions of the above Examples (present invention) all have a viscosity at 25 ° C. of 20 Pa · s or less, and the time until gelation starts when heated at 190 ° C. is 5 Within seconds.

1 Semiconductor chip (electronic component)
2 substrate 21 surface 211 wiring pattern 212 passivation film 22 surface 3 terminal (bump)
4 Circuit board (wiring board)
5 Substrate 51 Surface 6 Terminal 60 Wiring pattern 8 Hardened part (insulating part)
8 'Epoxy resin composition 9 Bonding tool 100 Semiconductor device

Claims (13)

An epoxy resin composition used for manufacturing a semiconductor device,
A liquid epoxy resin having two or more epoxy groups in the molecule, a curing agent, an inorganic filler, and a pregelling agent composed of a vinyl polymer;
The pregelator content is 2.0 wt% or more and 20 wt% or less,
An epoxy resin composition characterized by gelling before being cured by the epoxy resin when heated at 190 ° C.   The epoxy resin composition according to claim 1, wherein the epoxy resin includes a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and an aminophenol epoxy resin. The content of the bisphenol A type epoxy resin is 0.5 wt% or more and 4.0 wt% or less,
The content of the bisphenol F type epoxy resin is 7.0% by weight or more and 40% by weight or less,
The epoxy resin composition according to claim 2, wherein the content of the aminophenol epoxy resin is 10% by weight or more and 30% by weight or less.   The epoxy resin composition according to claim 2, wherein the epoxy resin further contains a 1,6-hexanediol epoxy resin.   The epoxy resin composition according to claim 4, wherein the content of the 1,6-hexanediol epoxy resin is 1.0% by weight or more and 6.0% by weight or less.   6. The epoxy resin composition has a viscosity at 25 ° C. of 20 Pa · s or less, and the time until gelation starts when heated at 190 ° C. is within 5 seconds. 6. The epoxy resin composition described in 1.   The epoxy resin composition according to claim 1, wherein the curing agent is a solid dispersion type amine adduct curing agent.   The epoxy resin composition according to any one of claims 1 to 7, wherein a content of the curing agent is 3 wt% or more and 30 wt% or less.   The epoxy resin composition according to any one of claims 1 to 8, wherein the pregelling agent has a weight average molecular weight of 100,000 to 20 million in an acetone-soluble component.   The epoxy resin composition according to any one of claims 1 to 9, wherein an acetone-soluble content of the pregelling agent is 2.0 wt% or more and 35 wt% or less.   11. The pregelling agent includes, as monomer components, methyl methacrylate: 70% by weight to 99% by weight and vinyl monomers other than methyl methacrylate: 1% by weight to 30% by weight. The epoxy resin composition according to any one of the above.   The vinyl monomer other than methyl methacrylate is one or more functional groups selected from the group consisting of a carboxyl group-containing vinyl monomer, a hydroxyl group-containing vinyl monomer, and a glycidyl group-containing vinyl monomer. The epoxy resin composition according to claim 11, comprising a group-containing monomer.   A semiconductor device manufactured using the epoxy resin composition according to claim 1.

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