JP2006028265A - Liquid encapsulation resin composition, electronic component device and its manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid encapsulation resin which does not cure before solder melts and cures quickly after bump joining and has high productivity and highly reliable heat resistance, an electronic component device using it and a manufacturing process of the electronic component device. <P>SOLUTION: The liquid encapsulation resin composition contains at least a cyanate ester resin having ≥2 cyanate ester groups in a molecule, has viscosity at 25°C of ≤50 Pa×s, a rate of increase in the viscosity at 25°C of ≤500% after it is left for 24 hours at 25°C, a gel time at 260°C of 1-120 seconds, a Tg after curing of 100-300°C and contains a compound having the function of a flux. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid sealing resin composition, an electronic component device, and a method for manufacturing an electronic component device.

Due to the demand for higher integration and higher density of semiconductor devices and smaller and thinner semiconductor packages, flip chip mounting packages that connect and mount semiconductor devices to printed circuit boards in a face-down manner have rapidly increased their production volume. Yes. This package mounting method enables a reduction in size and thickness by electrically connecting the surface of the semiconductor element and the wiring circuit board with metal bumps such as solder, instead of the conventional wire bonding connection. However, since the thermal expansion coefficients of the printed circuit board and the solder are different, thermal stress is likely to occur during the thermal shock test. For this reason, cracks are generated in the joint portions, and the operation reliability of the circuit is greatly reduced.
Therefore, sealing is performed by injecting a liquid sealing material (commonly referred to as an underfill material) for the purpose of relaxing thermal stress. However, in this method, before injecting the underfill material, the oxide film formed on the surface of the solder bump is reduced and removed, and the flux material is preliminarily used for the purpose of ensuring the wettability of the solder bump to the electrode on the substrate. The process is complicated because it is necessary to apply a process of washing and removing the residue of the flux material with an organic solvent after the semiconductor element with solder bumps is mounted on the substrate by coating on the substrate and heating in a reflow furnace. There was a problem. In addition, a large amount of waste liquid is generated in the flux material residue, which affects the environment. Furthermore, the bump pitch accompanying the increase in the density of the semiconductor element, the reduction of the gap between the semiconductor element and the substrate, it becomes technically difficult to extend the time for injecting the liquid sealing material and to finely clean the flux material residue. This complicates the assembly process and increases costs.

As a means for solving the above problems, a liquid sealing material is applied on a substrate in advance, a semiconductor element with solder bumps is temporarily mounted, and then the solder is melt-connected by heating in a reflow furnace, and then the liquid sealing is performed. Collective joining and sealing technology that hardens the stop material has appeared (for example, see Non-Patent Documents 1 and 2). The concept of this technology is that the liquid encapsulant contains a component having flux activity, so that it is possible to simultaneously bond and seal the semiconductor elements with solder bumps to the substrate, especially in the new assembly process. It is attracting attention as a technology. The liquid sealing material (commonly referred to as a non-flow underfill material) applied to such a process can have a low-viscosity liquid form, has a track record as a semiconductor application, and is cost effective. For reasons of low cost, epoxy resin is most frequently studied. Such a non-flow underfill material generally includes a liquid epoxy resin, a curing agent, and a flux component as main components, and a filler is added for the purpose of improving reliability (see, for example, Patent Documents 1, 2, and 3). .)
IEEE Transactions on components and packaging technologies, vol. 25, no. 1, p140 (2002) IEEE Transactions on components and packaging technologies, vol. 26, no. 2, p466 (2003) JP 2002-121358 A JP 2002-241469 A JP 2003-160639 A

  As the liquid sealing material, it is necessary to seal the resin material itself while bonding bumps formed of solder. Therefore, a material that does not cure before the solder melts and that quickly cures after bump bonding is desirable. . If the resin material is cured before the solder melts, bump connectivity will be extremely reduced. Conversely, if the curing is slow, post-cure will be required after joining by reflow or pulse heat, and assembly time will be required. It becomes long and deviates from the original purpose of the non-flow underfill material. In addition, since these materials are used by dispensing, it is desirable to have a low viscosity, and in terms of securing the pot life and pot life (shell life) of the product. Viscosity management is important. Furthermore, in order to increase reliability, (1) adhesion to an adherend, (2) moisture resistance reliability, (3) a low thermal expansion coefficient, (4) high Tg, etc. are important. Required as a characteristic. Moreover, it is necessary to be in a liquid form when supplying the product. However, the conventional epoxy resin-based underfill material has a narrow material design margin due to the restriction of liquidity, and it is extremely difficult to achieve both of the above characteristics.

As a result of intensive studies to solve these problems, the present invention has found that it can be effectively solved by using a cyanate ester resin having two or more cyanate ester groups in one molecule. Over time, the present invention has been completed.
The present invention relates to the following.
(1) Containing at least a cyanate ester resin having two or more cyanate ester groups in one molecule, the viscosity at 25 ° C. is 50 Pa · s or less, and the rate of increase in viscosity at 25 ° C. after standing for 24 hours at 25 ° C. A liquid sealing resin composition comprising a compound having a gel time of 500% or less, a gel time at 260 ° C. of 1 to 120 seconds, a Tg after curing of 100 to 300 ° C., and a flux function.
(2) A flux in which a solder ball is placed on a liquid sealing resin composition applied on a substrate with a copper foil, and when the solder ball is heated at 260 ° C. for 60 seconds, the wet spread ratio of the solder ball on the copper foil is 5% or more. The liquid sealing resin composition according to (1), which exhibits activity.

(3) The liquid sealing resin composition according to any one of (1) and (2), wherein the cyanate ester resin contains at least a cyanate ester resin that is liquid at normal temperature represented by the formula (I).
(4) As a compound having the flux function, a compound having at least two —OH functional groups (hydroxyl groups) per molecule as a compound having a flux function with respect to 100 parts by weight of the cyanate ester resin. The liquid sealing resin composition according to any one of (1) to (3), comprising 100 parts by weight.
(5) The liquid sealing resin composition according to (4), wherein the compound containing at least two —OH functional groups (hydroxyl groups) per molecule is an alcohol substance.

(6) A method of manufacturing an electronic component device in which a printed circuit board and an electronic component element are electrically joined by a connection electrode portion disposed in advance on at least one of the substrate and the element,
(A) On the wired circuit board, a solid or liquid compound at a room temperature having a flux function that has a melting temperature lower than the melting temperature of the connection electrode portion and a volatilization end temperature higher than the melting temperature of the connection electrode portion. Including the liquid sealing resin composition according to any one of (1) to (5),
(B) The electronic component element is mounted on the substrate with the liquid sealing resin composition of (a), and the element and the substrate are brought into contact with each other through the connection electrode portion that has pushed the liquid sealing resin composition. By temporarily mounting and filling the liquid sealing resin composition in the gap between the element and the substrate,
(C) When the substrate with the element of (b) is heated by a reflow furnace or an apparatus having a heater and a pressing portion, the connecting electrode portion is melted, and the device is mounted on the substrate by electrical bonding. Simultaneously, the manufacturing method of the electronic component apparatus which seals by hardening the said liquid sealing resin composition.
(7) An electronic component device sealed with the liquid sealing resin composition according to any one of (1) to (5).

  The liquid encapsulating resin composition of the present invention is used for sealing between an element of an electronic component device having a face-down structure and a printed circuit board, whereby the element bump and the printed circuit board electrode are metal-connected using a flux material. Later, without taking the conventional complicated process of injecting a sealing resin into the gap between the element and the printed circuit board, it is possible to easily perform batch bonding and resin sealing / metal bonding formation by sealing technology. A component device can be manufactured with high productivity, and an electronic component device having high heat resistance reliability can be obtained.

The liquid sealing resin composition of the present invention contains at least a cyanate ester resin having two or more cyanate ester groups in one molecule. Thereby, the material design which can adjust Tg after hardening in the range of 100-300 degreeC is made easy. The cyanate ester resin is not particularly limited as long as it is a compound having two or more cyanate ester groups in one molecule. Examples of such cyanate ester resins include 2,2′-bis (4-cyanatephenyl) isopropylidene and 2,2′-bis (4-cyanatephenyl) -1,1,1,3,3,3. -Hexafluoroisopropylidene, 1,1'-bis (4-cyanatephenyl) ethane, bis (4-cyanate-3,5-dimethylphenyl) methane, 1,3-bis (4-cyanatephenyl-1- (1) -Methylethylidene)) benzene, cyanated phenol-dicyclopentanediene adduct, cyanated novolak, bis (4-cyanatephenyl) thioether, etc. Among them, 1,1′-bis (4 -Cyanatephenyl) ethane, 1,3-bis (4-cyanatephenyl-1- (1-methylethyl) )) Benzene, cyanated phenol-dicyclopentanediene adduct, cyanated novolak (also known as polyphenol cyanate or 3-methylene-1,5-phenylene cyanate), preferably low viscosity, that is, a viscosity at 25 ° C. of 50 Pa · s or less 1,1'-bis (4-cyanatephenyl) ethane (also known as 4,4'-ethylidenediphenyl dicyanate or cyanate ethylidenedi-4,1-phenylene ester represented by the following formula (I) ) Is more preferable. These can be used alone or in combination of two or more. In this case, the blending ratio is adjusted so that the viscosity at 25 ° C. does not exceed 50 Pa · s. In addition, said "liquid at normal temperature" means showing a liquid state at 10-30 degreeC.

  Generally, a cyanate ester resin having two or more cyanate ester groups in one molecule easily undergoes crosslinking by a trimerization reaction by heating in the presence of a catalyst to give a cured resin having a high Tg. Examples of the catalyst include metal complexes such as metal naphthenates such as cobalt, zinc, iron, copper, chromium, manganese, nickel, and titanium, acetylacetonate, salts of derivatives thereof, various carboxylates, alkoxides, and the like. These organic acid salts may be used alone or in combination. The amount added is preferably 0.001 to 2 parts by weight, more preferably 0.005 to 1 part by weight, and still more preferably 0.005 to 0.5 part by weight, based on 100 parts by weight of the total cyanate ester resin. Within these ranges, the addition amount is adjusted so that the rate of increase in viscosity at 25 ° C. after standing at 25 ° C. for 24 hours is 500% or less and the gel time at 260 ° C. is 1 to 120 seconds. When the amount is less than 0.001 part by weight, the reaction promoting effect is low, the curing time becomes long, and the productivity tends to be inferior. On the other hand, when the amount is more than 2 parts by weight, the reaction promoting effect becomes too high, and the usable time (pot life) and storage time (shell life) as a product tend to be impaired.

The liquid sealing resin composition of the present invention is liquid at 25 ° C. In the present specification, “liquid” means fluidity, and the viscosity is 25 ° C. after standing at 25 ° C. for 24 hours at a viscosity of 50 Pa · s or less at 25 ° C. from the viewpoint of excellent fluid filling properties. The rate of increase in the viscosity is 500% or less. The viscosity is a value when measured using an E-type rotational viscometer under conditions of 25 ° C. and 5 rpm. The viscosity increase rate after being left for 24 hours was calculated by the following formula (1).
Viscosity increase rate after standing for 24 hours = (viscosity after standing at 25 ° C. for 24 hours−viscosity immediately after blending) × 100
/ Viscosity immediately after compounding (Formula 1)
The viscosity at 25 ° C. is more preferably 30 Pa · s or less, and further preferably 10 Pa · s or less. If the viscosity is higher than 50 Pa · s, dispensing tends to be difficult. The rate of increase in viscosity at 25 ° C. after standing at 25 ° C. for 24 hours is 500% or less, more preferably 300% or less, and even more preferably 100% or less. When the viscosity increase rate exceeds 500%, the pot life (pot life) and storage time (shell life) as a product are shortened, and the productivity tends to be impaired.

  The liquid sealing resin composition of the present invention is characterized in that the gel time at 260 ° C. is 1 to 120 seconds, more preferably 5 to 90 seconds, and still more preferably 10 to 60 seconds. . The gel time is a value obtained by measuring the time until gelation starts after an appropriate amount of the blended liquid sealing resin composition is placed on a hot plate at 260 ° C. using a gel timer. If the gel time is less than 1 second, connection tends to be difficult, and if the gel time exceeds 120 seconds, productivity tends to be impaired.

  The liquid encapsulating resin composition of the present invention is characterized in that the Tg after curing is 100 to 300 ° C, more preferably 120 to 280 ° C, and even more preferably 150 to 250 ° C. The above Tg means that the cured product obtained by gelling the liquid sealing resin composition on a 260 ° C. hot plate and then heating it in an oven at 165 ° C. for 2 hours is converted into a DSC (differential scanning calorimeter). Sample amount: 10 mg, temperature increase rate: 10 ° C./min, temperature increase to 25-300 ° C., temperature increase: measured at two times. When the Tg is less than 100 ° C., the connection reliability at the time of high-temperature reflow tends to be lowered. Tend.

  The liquid sealing resin composition of the present invention contains a compound having a flux function (hereinafter referred to as a flux agent). Thereby, the liquid sealing resin composition of this invention has a flux function. The flux function is to remove the oxide film, organic matter, etc. on the metal surfaces to be joined at the time of joining to the substrate, for example, soldering, preventing the progress of oxidation during heating, and reducing the surface tension of the molten solder. It is a function.

The liquid encapsulating resin composition of the present invention is obtained by placing a solder ball on the liquid encapsulating resin composition coated on a substrate with a copper foil and wetting the solder ball on the copper foil when heated at 260 ° C. for 60 seconds. The spreading rate is preferably 5% or more. 4 to 6 are schematic cross-sectional views illustrating an example of a solder ball wetting spread rate test process. As shown in FIG. 4, the solder ball wetting and spreading rate is obtained by applying a liquid sealing resin composition 7 on a copper foil substrate (MCL-E-679, manufactured by Hitachi Chemical Co., Ltd.) 5. Installed on an 80 ° C. hot platen, the solder balls (M705 (Sn / 3.0Ag / 0.5Cu), ball diameter, manufactured by Senju Metal Industry Co., Ltd.) in the liquid sealing resin composition 7 as shown in FIG. 6: 200 μm, melting point: 220 ° C.) 4 pieces were added and left on a heating plate at 260 ° C. for 60 seconds to melt the solder balls 6 and then cooled to room temperature, and then the test piece shown in FIG. The maximum diameter S of the solder ball 6 after wetting and spreading is measured by cross-sectional observation, and is an average value calculated from each of the four maximum diameters S by the following equation (2).
Solder ball wetting spread rate = maximum diameter S of solder ball 6 after wetting spread−solder ball diameter before wetting spread)) × 100 / solder ball diameter before wetting spread (Formula 2)
If the wet spreading rate at this time is less than 5%, there is a tendency that good connection between the solder balls and the printed circuit board cannot be obtained.

The flux agent for imparting a flux function to the liquid sealing resin composition of the present invention is a compound or composition that is solid or liquid at room temperature and can impart flux activity to the liquid sealing resin composition. Although there is no particular limitation, flux agents such as amine hydrohalide salts that have been generally used as flux liquids from the past tend to become ions when subjected to moisture absorption, resulting in a significant reduction in electrical properties. Tend to bring about. Preferred fluxing agents include, for example, organic compounds containing highly acidic carboxylic acids such as compounds having phenolic hydroxyl groups and carboxylic acids, acid anhydrides containing carboxylic acids such as trimellitic acid, and compounds having hydroquinone skeletons. In addition to acids and the like, compounds containing at least two —OH functional groups (hydroxyl groups) per molecule can be mentioned. Examples of such a compound having an —OH functional group (hydroxyl group) are compounds having an alcoholic hydroxyl group or a phenolic hydroxyl group, and examples thereof include an alcohol substance (alcohol compound), a phenolic compound, and a phenoxy resin. These fluxing agents can be used alone or in combination of two or more.
In addition, in order to perform good bonding with the substrate, for example, soldering, when mounting the electronic component, in addition to removing the oxide film, a connection electrode portion provided on at least one of the electronic component element and the substrate is configured. It is necessary to reduce the interfacial tension of the material (for example, solder) to ensure good wetting and spreading. For this purpose, it is preferable that when the connecting electrode portion is in a liquid state, the volatilization of the fluxing agent is not completed and the liquid state is in a liquid state. That is, for example, when the connecting electrode portion is made of solder, the TG% (thermal weight change rate) by the TGA (Thermal Gravity Analysis) method of the flux agent is 0%, that is, the lowest temperature at which the remaining weight becomes 0 ( In the following, the volatilization end temperature is also higher than the melting temperature of the solder, and when a solid flux agent is selected at room temperature, the mp (melting temperature) is equal to or lower than the mounting temperature (that is, the melting temperature of the solder). A fluxing agent is preferred. As described above, the fluxing agent is appropriately selected in consideration of the melting temperature of the material of the connection electrode part at the time of mounting. The temperature of TG% = 0% (the volatilization end temperature) is a value when measured at a heating rate of 10 ° C./min, an Air flow rate of 200 mL / min, and a sample weight of 8 to 10 mg.

The above fluxing agent is preferably a compound containing at least two —OH functional groups (hydroxyl groups) in one molecule. Among them, an alcohol substance is preferable in that it has a low viscosity and can suppress an increase in viscosity after standing. The alcohol substance is not particularly limited as long as it is a compound containing at least two alcoholic —OH functional groups (hydroxyl groups) in the molecule. Examples of such alcohol substances include 1,3-dioxane-5,5-dimethanol, 1,5-pentanediol, 2,5-furandethanol, n-butyldiethanolamine, ethyldiethanolamine, diethanolamine, diethylene glycol, tetra Ethylene glycol, triethylene glycol, hexaethylene glycol, pentaethylene glycol, 1,2,3-hexanetriol, 1,2,4-butanetriol, 1,2,6-hexanetriol, 2,3,4-trihydroxy Benzophenone, 2 ', 3', 4'-trihydroxyacetophenone, 3-methylpentane-1,3,5-triol, glycerin, triethanolamine, trimethylolethane, trimethylolpropane, pyrogallol, erythri , N, N-bis (2-hydroxyethyl) isopropanolamine, pentaerythritol, bis (2-hydroxymethyl) iminotris (hydroxymethyl) methane, ribitol, sorbitol, 2,4-diethyl-1,5-pentanediol , Propylene glycol monomethyl ether, propylene glycol monoethyl ether, 1,3-butylene glycol, 2-ethyl-1,3-hexanediol, etc., monosaccharides such as triose, tetrose, pentose, hexose, glucose, etc. ,
2,4-diethyl-1,5-pentanediol-adipic acid polycondensate represented by the following formula (II):
(In the formula (II), n is an integer of 1 or more.)
Butylethylpropanediol-adipic acid polycondensate represented by the following formula (III):
(In the formula (III), n is an integer of 1 or more.)
Polyols, such as these, are mentioned, One or more types can be selected.
The above alcohol substance is compatible with other components contained in the liquid sealing resin composition of the present invention, improves the contact efficiency with the bump surface, and can effectively reduce and remove the oxide film formed on the surface. In addition, for the purpose of suppressing the viscosity at 25 ° C. to 50 Pa · s or less, a polyhydric alcohol substance that is liquid at room temperature and highly compatible with the resin composition is preferable.

  The content of the above fluxing agent is preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the cyanate ester resin. This content is particularly preferred when the fluxing agent is a compound containing at least two —OH functional groups (hydroxyl groups) per molecule. If the amount is less than 0.1 parts by weight, there is a tendency that the flux activity cannot be effectively imparted. If the amount exceeds 100 parts by weight, the Tg after curing tends to be less than 100 ° C., and the heat resistance tends to be impaired. Within a certain range, the addition amount is adjusted so that the rate of increase in viscosity at 25 ° C. after standing at 25 ° C. for 24 hours is 500% or less.

The liquid sealing resin composition of the present invention has (1) a viscosity at 25 ° C. of 50 Pa · s or less, (2) an increase rate of viscosity at 25 ° C. after standing at 25 ° C. for 24 hours, and (3) 260 In order to effectively impart the properties of a gel time of 1 to 120 seconds at 4 ° C. and (4) a Tg of 100 to 300 ° C. after curing, and in some cases, to impart flexibility, the cyanate is optionally added. In addition to the ester resin, one or more kinds of resins such as epoxy resin, bismaleimide resin, phenol resin, silicone resin, urethane resin, bisallyl nadiimide, triallyl isocyanurate, and benzoxazine resin can be combined. In particular, in order to set the viscosity at 25 ° C. to 50 Pa · s or less, it is preferable to select a liquid resin as the resin. As the bismaleimide resin, polytetramethylene ether glycol di (2-maleimidoacetate) represented by the following formula (IV) is preferably used because it is liquid and can impart flexibility.
(In the formula (IV), n is an integer of 2 to 5.)
As for the bisallylnadiimide, 1,6-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) hexane represented by the following formula (V) is used. It is preferably used because it is liquid and can impart flexibility.
(In the formula (V), n = 6.)
In addition, when combining these resin, in order to accelerate | stimulate hardening, a hardening | curing agent, an accelerator, a catalyst, etc. can be added as needed. At this time, the addition amount is adjusted so that (2) the rate of increase in viscosity at 25 ° C. after standing at 25 ° C. for 24 hours is 500% or less, and (3) the gel time at 260 ° C. is 1 to 120 seconds. The content of these resins is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the cyanate ester resin. If the amount is less than 1 part by weight, there is a tendency that the effect of the modification cannot be obtained. If the amount exceeds 100 parts by weight, there is a high possibility that the Tg after curing is less than 100 ° C., and the heat resistance tends to be impaired.

  In addition to the above resin, a thermoplastic resin may be added as necessary. Examples of the thermoplastic resin that can be added include polyamide resin, polyimide resin, urethane resin, silicone resin, phenoxy resin, acrylic copolymer, and the like. Since the phenoxy resin contains a hydroxyl group in the side chain and has flux activity, it can be used as a flux agent. Furthermore, addition of a silicone rubber filler or the like is also effective in that flexibility can be imparted. These resins can be used alone or in combination of two or more. The content of these resins is preferably 1 to 100 parts by weight with respect to 100 parts by weight of the cyanate ester resin. If the amount is less than 1 part by weight, the effect of modification tends to be lost, and if it exceeds 100 parts by weight, the heat resistance tends to be impaired.

  Since the liquid sealing resin composition of the present invention is used for sealing electronic component elements such as semiconductor elements, high reliability is required. In particular, it is preferable to add an inorganic filler in order to bring the water resistance and linear expansion coefficient closer to the adherend. Examples of such inorganic fillers include aluminum nitride, alumina, silica, and the like, and silica particles are preferable from the viewpoint of heat dissipation and cost, and more preferable if they are low radiation. There are spherical shapes, crushed shapes, flakes, and the like, but spherical shapes are desirable because the filler can be highly filled. Moreover, as for the addition amount of a filler, 10 to 80 weight% is desirable with respect to the whole composition. If it is less than 10% by weight, the moisture resistance and the thermal expansion coefficient of the cured product tend to increase, and the dispersion of the filler also tends to occur. On the other hand, if it exceeds 80% by weight, the viscosity of the resulting composition becomes too high, and the flow characteristics at the time of joining tend to deteriorate. These inorganic fillers can be used alone or in combination of two or more. Mixing and kneading of the filler can be performed by appropriately combining dispersers such as a normal stirrer, a raking machine, a triple roll, and a ball mill.

  In addition to the above-described components, additives such as a coupling agent, a diluent, a flame retardant, and an antifoaming agent can be added to the liquid sealing resin composition of the present invention as necessary.

  The liquid sealing resin composition of the present invention can be produced, for example, as follows. That is, a predetermined amount of a resin containing a cyanate ester resin, a fluxing agent such as a compound containing at least two —OH functional groups (hydroxyl groups) in a molecule, and an inorganic filler, and various components as necessary. For example, a composition containing a predetermined amount of a curing agent, a curing accelerator, a plasticizer, a silane coupling agent, etc. is applied to a kneader such as a stirring kettle and melt mixed. Next, if necessary, this is filtered using a filter or the like, and then degassed under reduced pressure, whereby the intended liquid sealing resin composition can be produced.

In FIG. 1, an example of the electronic component apparatus of this invention manufactured with the liquid sealing resin composition of this invention is shown with a longitudinal cross-sectional view. As shown in FIG. 1, a structure in which a semiconductor element 3 is mounted on one side of a printed circuit board 1 via a plurality of connection electrode portions 2 is employed. A sealing resin layer 4 that is a cured product of the liquid sealing resin composition of the present invention is formed between the printed circuit board 1 and the semiconductor element 3.
The plurality of connection electrode portions 2 that electrically connect the wired circuit board 1 and the semiconductor element 3 may be disposed in advance on the surface of the wired circuit board 1 or disposed on the surface of the semiconductor element 3. May be. Furthermore, it may be previously arranged on both the printed circuit board 1 surface and the semiconductor element 3 surface.

The material of the printed circuit board 1 is not particularly limited, but is roughly classified into a ceramic substrate and a plastic substrate. Examples of the plastic substrate include an epoxy substrate, a bismaleimide triazine substrate, and a polyimide substrate. . Even when the liquid sealing resin composition of the present invention cannot set the bonding temperature to a high temperature due to the problem of heat resistance, such as a combination of a plastic substrate and a connecting electrode portion using low melting point solder, It does not specifically limit and is used suitably.
The material of the plurality of connection electrode portions 2 is not particularly limited, and examples thereof include a low melting point by solder and a high melting point bump, a tin bump, a silver-tin bump, a silver-tin-copper bump, and the like. Further, for the electrode part on the circuit wiring board made of the above-mentioned material, the connection electrode part 2 in the figure may be a gold bump, a copper bump or the like.
The semiconductor element 3 is not specifically limited, What is normally used can be used. For example, various semiconductors such as elemental semiconductors such as silicon and germanium, and compound semiconductors such as gallium arsenide and indium phosphide are used.

A method for manufacturing an electronic component device using the liquid sealing resin composition of the present invention will be described in order with reference to the drawings. 2 and 3 are schematic cross-sectional views showing an example of the manufacturing process of the electronic component device.
(1) First, as shown in FIG. 2, on the printed circuit board 1, the melting temperature is equal to or lower than the melting temperature of the connection electrode portion 2, and the volatilization end temperature is higher than the melting temperature of the connection electrode portion. The liquid sealing resin composition 7 of the present invention containing a state or liquid flux agent is applied by a dispensing method.
(2) Next, as shown in FIG. 3, a plurality of connection electrode portions (joint balls) for electrical bonding to the substrate at predetermined positions on the liquid sealing resin composition 7 of the substrate of (1). 2 is mounted, the liquid sealing resin composition 7 is melted on a heating stage to be in a molten state, and the connecting electrode portion 2 of the semiconductor element 3 is in a molten state. The object 7 is pushed away, the element 3 and the substrate 1 are brought into contact with each other through the connection electrode portion 2 and temporarily mounted, and a molten liquid seal is placed in the gap between the semiconductor element 3 and the printed circuit board 1. The stop resin composition 7 is filled.
(3) Thereafter, metal bonding by solder reflow is performed for mounting, and at the same time, the liquid sealing resin composition 7 is cured, thereby sealing the gap and forming the sealing resin layer 4 (see FIG. 1). At this time, the solder reflow method in which the solder is melted by heating the substrate and the semiconductor element 3 is electrically bonded to the substrate is a bonding method using a reflow furnace. A bonding method in which the heater portion is heated to a temperature equal to or higher than the melting point of the solder simultaneously with the mounting of the element to melt the solder may be used. In this way, the electronic component device shown in FIG. 1 is manufactured. Examples of the method for applying the liquid sealing resin composition 7 on the printed circuit board 1 include a printing method and a transfer method in addition to the dispensing method.

In the above-described method for manufacturing an electronic component device, the case where the semiconductor element 3 provided with the plurality of connection electrode portions 2 is used has been described. However, the present invention is not limited to this. An electrode provided with the connecting electrode portion 2 may be used.
Further, the thickness and weight of the liquid sealing resin composition 7 are the same as those described above, and the size of the semiconductor element 3 to be mounted and the size of the spherical connection electrode provided on the semiconductor element, that is, the semiconductor element 3 and the wiring. It is set appropriately depending on the volume occupied by the sealing resin layer 4 formed by filling the gap with the circuit board 1 and sealing.
In the method for manufacturing the electronic component device, the liquid sealing resin composition 7 does not necessarily have to be heated and melted during the temporary mounting of (2). Furthermore, as the heating temperature when the liquid sealing resin composition 7 is heated to a molten state, the heat resistance of the semiconductor element 3 and the printed circuit board 1, the melting point of the connection electrode portion 2, and the liquid sealing resin composition It is appropriately set in consideration of the softening point, heat resistance, etc. of the object 7.

  Next, the present invention will be described based on examples and comparative examples. In addition, this invention is not limited by these Examples.

Example 1
Cyanate ester resin (1,1′-bis (4-cyanatephenyl) ethane, product name; Primaset LECy) 100 parts by weight from Lonza, 0.1 part by weight cobalt naphthenate as a catalyst, Meiwa Kasei Co., Ltd. 1.9 parts by weight of allyl group-modified liquid phenol novolac resin MEH-8000H, 10 parts by weight of pentaethylene glycol, 190 parts by weight of spherical silica filler SE-1 (average particle size: 1.0 μm) manufactured by Tokuyama Corporation, Nippon Unicar Co., Ltd. Weighed 1 part by weight of a silane coupling agent (γ-glycidpropyltrimethoxysilane, product name: A-187) manufactured by the company, kneaded and dispersed with three rolls, and then subjected to a vacuum degassing treatment to obtain a liquid sealing resin Composition A was obtained.

Example 2
Cyanate ester resin (1,1′-bis (4-cyanatephenyl) ethane, product name; Primaset LECy) 100 parts by weight, zinc acetylacetonate 0.01 parts by weight as catalyst, polyester manufactured by Kyowa Hakko Kogyo Co., Ltd. 50 parts by weight of polyol (product name: Kyowapol 2000PA), 190 parts by weight of spherical silica filler SE-1 (average particle size: 1.0 μm) manufactured by Tokuyama Corporation, silane coupling agent (γ-glycid manufactured by Nihon Unicar Co., Ltd.) Propyltrimethoxysilane, product name: A-187) 1 part by weight was weighed, kneaded and dispersed with three rolls, and then subjected to vacuum degassing to obtain a liquid sealing resin composition B.

Example 3
Cyanate ester resin (1,1′-bis (4-cyanatephenyl) ethane, product name; Primaset LECy) 100 parts by weight from Lonza, 0.1 part by weight cobalt naphthenate as a catalyst, Meiwa Kasei Co., Ltd. 1.9 parts by weight of allyl group-modified liquid phenol novolak resin MEH-8000H, polyether bismaleimide acetate (polytetramethylene ether glycol di (2-maleimide acetate), manufactured by Dainippon Ink & Chemicals, Inc., product name; MIA200 ) 30 parts by weight, 5 parts by weight of gentisic acid, 190 parts by weight of spherical silica filler SE-1 (average particle size: 1.0 μm) manufactured by Tokuyama Corporation, silane coupling agent (γ-glycidpropylpropyltri) manufactured by Nippon Unicar Co., Ltd. Methoxysilane, product name; A-187) single An amount part was weighed, kneaded and dispersed with three rolls, and then subjected to a vacuum detachment treatment to obtain a liquid sealing resin composition C.

Example 4
Cyanate ester resin (1,1′-bis (4-cyanatephenyl) ethane, product name; Primaset LECy) 100 parts by weight, 0.5 part by weight of copper naphthenate as a catalyst, and Meiwa Kasei Co., Ltd. as a promoter 9.5 parts by weight of an allyl group-modified liquid phenol novolac resin MEH-8000H, bisallylnadiimide (1,6-bis (allylbicyclo [2.2.1] hept-5-ene-2, manufactured by Maruzen Petrochemical Co., Ltd.) , 3-dicarboximide) hexane, product name: BANI-H) 20 parts by weight, phenoxy resin (product name: PKHP-200) 5 parts by weight, Tokuyama Corporation spherical silica filler SE-1 ( Average particle size: 1.0 μm) 190 parts by weight, Nihon Unicar Co., Ltd. silane coupling agent (γ-glycidpropyl) Rimethoxysilane, product name: A-187) 1 part by weight was weighed, kneaded and dispersed with three rolls, and then subjected to a vacuum detachment treatment to obtain a liquid sealing resin composition D.

Example 5
100 parts by weight of cyanate ester resin (1,1′-bis (4-cyanatephenyl) ethane, product name; Primaset LECy) manufactured by Lonza, 0.01 parts by weight of zinc acetylacetonate as a catalyst, Toray Dow Corning Silicone Co., Ltd. Company-made silicone powder (product name: Trefil E-601) 10 parts by weight, hexaethylene glycol 10 parts by weight, Tokuyama Co., Ltd. spherical silica filler SE-1 (average particle size: 1.0 μm) 190 parts by weight, Nippon Unicar Co., Ltd. Weighed 1 part by weight of a silane coupling agent (γ-glycidpropyltrimethoxysilane, product name: A-187) manufactured by the company, kneaded and dispersed with three rolls, and then subjected to a vacuum degassing treatment to obtain a liquid sealing resin Composition E was obtained.

Comparative Example 1
100 parts by weight of bisphenol F type epoxy resin (product name; YDF-8170C, epoxy equivalent: 160, property: liquid) manufactured by Toto Kasei Co., Ltd., acid anhydride-based curing agent (product name: Epicure YH306) manufactured by Japan Epoxy Resin Co., Ltd. 146 parts by weight, 1.5 parts by weight of an imidazole-based curing accelerator manufactured by Shikoku Kasei Kogyo Co., Ltd. (product name: Curesol 2P4MHZ property: solid), spherical silica filler SE-1 manufactured by Tokuyama Corporation (average particle size: 1.0 μm) ) 190 parts by weight, Nihon Unicar Co., Ltd. silane coupling agent (γ-glycidpropyl propyltrimethoxysilane, product name: A-187) 1 part by weight was weighed, kneaded and dispersed with three rolls, then vacuum degassed A foam treatment was performed to obtain a liquid sealing resin composition F.

Comparative Example 2
Bisphenol F type epoxy resin (product name; YDF-8170C, epoxy equivalent: 160, property: liquid) manufactured by Toto Kasei Co., Ltd., phenol novolac resin (product name; H-1, OH equivalent: manufactured by Meiwa Kasei Co., Ltd.) 106, property: solid) 66 parts by weight, Shikoku Kasei Kogyo Co., Ltd. imidazole curing accelerator (product name: Curezol 2P4MHZ, property: solid) 1 part by weight, triethanolamine 10 parts by weight, Tokuyama Corporation spherical 190 parts by weight of silica filler SE-1 (average particle size: 1.0 μm) and 1 part by weight of a silane coupling agent (γ-glycidpropyltrimethoxysilane, product name: A-187) manufactured by Nihon Unicar Co., Ltd. were weighed. After kneading and dispersing with three rolls, vacuum defoaming treatment was performed to obtain a liquid sealing resin composition G.

Comparative Example 3
Cyanate ester resin (1,1′-bis (4-cyanatephenyl) ethane, product name; Primaset LECy) 100 parts by weight from Lonza, 0.1 part by weight cobalt naphthenate as a catalyst, Meiwa Kasei Co., Ltd. 1.9 parts by weight of allyl group-modified liquid phenol novolac resin MEH-8000H, 190 parts by weight of spherical silica filler SE-1 (average particle size: 1.0 μm) manufactured by Tokuyama Corporation, silane coupling agent manufactured by Nihon Unicar Corporation ( 1 part by weight of γ-glycidpropyltrimethoxysilane, product name: A-187) was weighed, kneaded and dispersed with three rolls, and then subjected to vacuum degassing treatment to obtain a liquid sealing resin composition H.

Comparative Example 4
Bisphenol F type epoxy resin (product name; YDF-8170C, epoxy equivalent: 160, property: liquid) manufactured by Toto Kasei Co., Ltd., phenol novolac resin (product name; H-1, OH equivalent: manufactured by Meiwa Kasei Co., Ltd.) 106, property: solid state 62 parts by weight, Japan Epoxy Resin Co., Ltd. acid anhydride curing agent 62 parts by weight (product name; Epicure YH306), Shikoku Kasei Kogyo Co., Ltd. imidazole curing accelerator (product name: Curezol) 2P4MHZ, properties: 1 part by weight, Tokuyama Co., Ltd. spherical silica filler SE-1 (average particle size: 1.0 μm) 190 parts by weight, Nihon Unicar Co., Ltd. silane coupling agent (γ-glycidpropylpropyltri) Methoxysilane, product name: A-187) Weigh 1 part by weight, knead and disperse with 3 rolls, then vacuum release A foam treatment was performed to obtain a liquid sealing resin composition I.

The resin composition characteristics of Examples 1 to 5 are shown in Table 1, and the resin composition characteristics of Comparative Examples 1 to 4 are shown in Table 2, respectively.
The viscosity in the table is a value when measured using an E-type rotational viscometer under the conditions of 25 ° C. and 5 rpm. The viscosity increase rate is the viscosity increase rate after being left at 25 ° C. for 24 hours, and was calculated by the following formula (1).
Viscosity increase rate after standing for 24 hours = (viscosity after standing at 25 ° C. for 24 hours−viscosity immediately after blending) × 100
/ Viscosity immediately after compounding (Formula 1)
The gel time in the table is a value obtained by measuring the time until gelation starts after a suitable amount of the blended liquid sealing resin composition is placed on a hot plate at 260 ° C. using a gel timer. Moreover, Tg is a value when the cured product obtained by gelling the liquid sealing resin composition on a 260 ° C. hot plate and then heating in a 165 ° C. oven for 1 hour is measured by DSC. is there. The DSC measurement conditions are as follows. Sample amount: about 10 mg, temperature increase rate: 10 ° C./min, temperature increase from 25 ° C. to 300 ° C., temperature increase: 2 times.

With the solder ball wetting spread rate in the table, as shown in FIG. 4, the liquid sealing resin composition 7 is applied on the copper foil substrate (MCL-E-679 manufactured by Hitachi Chemical Co., Ltd.) 5. This was placed on an 80 ° C. hot platen, and solder balls (M705 (Sn / 3.0Ag / 0.5Cu), manufactured by Senju Metal Industry Co., Ltd.) in the liquid sealing resin composition 7 as shown in FIG. Four balls 6 (ball diameter: 200 μm, melting point: 220 ° C.) were added and left on a heating plate at 260 ° C. for 60 seconds to melt the solder balls 6. After cooling to room temperature, the cross section of the test piece is observed as shown in FIG. 6, the maximum diameter S of the solder ball 6 after wetting and spreading is measured, and calculated from each of the four maximum diameters S by the following equation (2). This is the average of the values obtained.
Solder ball wetting spread rate = (maximum diameter S of solder ball 6 after wetting spread−solder ball diameter before wetting spreading) × 100 / solder ball diameter before wetting spreading (Equation 2)

As can be seen from Table 1 and Table 2, Comparative Examples 1, 2, and 4 not containing a cyanate ester resin having two or more cyanate ester groups in one molecule tend to have a high viscosity at 25 ° C. and a viscosity increase rate. Therefore, coating is difficult and workability is low, and the working time and storage time are short, and the productivity may be low. Tg involved in heat resistance reliability also tends to be low. Further, Comparative Example 3 including the cyanate ester resin but not including the compound having a flux function is inferior in productivity and connection reliability because the solder ball wetting spread rate is poor. On the other hand, it can be seen that the resin compositions of Examples 1 to 5 can be expected to ensure high productivity and good heat resistance reliability while maintaining good workability and good connection reliability.

FIG. 1 is a schematic cross-sectional view illustrating an example of an electronic component device. FIG. 2 is a schematic cross-sectional view showing an example of the manufacturing process of the electronic component device. FIG. 3 is a schematic cross-sectional view showing an example of the manufacturing process of the electronic component device. FIG. 4 is a schematic cross-sectional view showing one step of the solder wetting spread rate test. FIG. 5 is a schematic cross-sectional view showing the next step of the solder wetting spread rate test. FIG. 6 is a schematic cross-sectional view showing a further next step of the solder wetting spread rate test.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wiring circuit board 2 Electrode part 3 for connection 3 Semiconductor element 4 Sealing resin layer 5 Copper foil board | substrate 6 Solder ball 7 Liquid sealing resin composition

Claims (7)

  Contains at least a cyanate ester resin having two or more cyanate ester groups in one molecule, has a viscosity at 25 ° C. of 50 Pa · s or less, and a viscosity increase rate at 25 ° C. after standing at 25 ° C. for 24 hours is 500% or less A liquid sealing resin composition comprising a compound having a gel time at 260 ° C. of 1 to 120 seconds, a Tg after curing of 100 to 300 ° C., and a flux function.   A solder ball is placed on the liquid sealing resin composition applied onto the substrate with copper foil, and when the solder ball is heated at 260 ° C. for 60 seconds, the solder ball exhibits a flux activity of 5% or more on the copper foil. The liquid sealing resin composition according to claim 1. The liquid sealing resin composition according to any one of claims 1 and 2, wherein the cyanate ester resin contains at least a cyanate ester resin that is liquid at normal temperature represented by the formula (I).
  The compound having 0.1 to 100 parts by weight of a compound having at least two —OH functional groups (hydroxyl groups) per molecule as the compound having the flux function, based on 100 parts by weight of the cyanate ester resin. The liquid sealing resin composition in any one of 1-3.   The liquid sealing resin composition according to claim 4, wherein the compound containing at least two —OH functional groups (hydroxyl groups) per molecule is an alcohol substance. A method of manufacturing an electronic component device in which a printed circuit board and an electronic component element are electrically joined to each other by a connection electrode portion disposed in advance on at least one of the substrate and the element,
(A) On the wiring circuit board, the melting temperature is equal to or lower than the melting temperature of the connecting electrode portion, and the volatilization end temperature is higher than the melting temperature of the connecting electrode portion, which is solid or liquid at room temperature having a flux function. Applying the liquid sealing resin composition according to any one of claims 1 to 5, comprising a compound,
(B) The electronic component element is mounted on the substrate with the liquid sealing resin composition of (a), and the element and the substrate are brought into contact with each other through the connection electrode portion that has pushed the liquid sealing resin composition. By temporarily mounting and filling the liquid sealing resin composition in the gap between the element and the substrate,
(C) When the substrate with the element of (b) is heated by a reflow furnace or an apparatus having a heater and a pressing portion, the connecting electrode portion is melted, and the device is mounted on the substrate by electrical bonding. Simultaneously, the manufacturing method of the electronic component apparatus which seals by hardening the said liquid sealing resin composition.   An electronic component device sealed with the liquid sealing resin composition according to claim 1.