JP2001053112A - Method for connecting circuit substrate and composite circuit substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for connecting a circuit substrate, which reduces voids left behind in a resinous composition layer, and moreover decreases thermal stresses between the resin composition layer, a semiconductor chip and a substrate with high reliability, and provide a composite circuit substrate connecting circuit substrates with each other. SOLUTION: A first resin composition layer 31 is formed on a wiring plane of a first circuit substrate 1, and a second resin composition layer 32 of a melting viscosity lower than the first resin composition layer is formed on the first resin composition layer 31 or a wiring plane of a second circuit substrate 5, and the wiring planes of the first and second circuit substrates are stationed counterposed to each other, so as to interpose bump electrodes 2, 6, and an interval between the first and second circuit substrates is joined with the resinous composition, and also an interval between mutual wirings of the circuit substrate is electrically connected with a bump electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting circuit substrates such as a semiconductor chip and a wiring substrate, and a composite circuit substrate in which the circuit substrates are connected.

[0002]

2. Description of the Related Art Conventionally, in order to manufacture a resin-encapsulated semiconductor device by connecting a semiconductor chip to a wiring board, it is necessary to form the semiconductor device on a wiring surface of the semiconductor chip and on an electrode pad on a wiring forming surface on the wiring board. A method has been developed in which a bump electrode is formed, a bump electrode of a semiconductor chip is pressure-bonded to a wiring board, and then an underfill resin is injected into a gap between a wiring surface of the semiconductor chip and a wiring surface of the wiring board. However, in such a manufacturing method, not only time is required for the resin sealing step with the underfill resin, but also the fluidity of the resin and the amount of the filler are restricted, so that it is difficult to secure sufficient reliability. .

Also, unlike the above-described underfill method, a method has been developed in which a resin composition is interposed between a semiconductor chip and a wiring board in advance, and then the semiconductor chip and the wiring board are electrically joined. I have. For example, JP-A-9-237806 discloses that a thermoplastic resin layer is formed on a semiconductor chip provided with bump electrodes, and this thermoplastic resin layer is melted when the semiconductor chip is mounted, and the semiconductor chip is joined to a mounting substrate. In addition, it is shown that sealing can be performed together.

However, when a resin composition layer is formed on a semiconductor chip or a wiring board, it is difficult to form a flat resin composition layer due to the presence of bump electrodes, warpage or undulation of the wiring board, and the like. . In the case where the surface of the resin composition layer has irregularities, when the semiconductor chip and the wiring board are joined in this state, the air layer remains in the resin composition layer and becomes void. The voids accumulate water when absorbing moisture, accelerating the corrosion of the wiring of the semiconductor chip, and when the bump electrodes are formed of a solder material, the solder bumps flow out during mounting and a bridge is formed between the solder bumps, resulting in short-circuit failure. May occur.

A method for suppressing voids is disclosed in, for example, Japanese Patent Application Laid-Open No. 58-73126.
In this publication, a resin mold member is applied to a circuit board (wiring board) in advance, the semiconductor chip is mounted on the circuit board via the resin mold member, and the semiconductor chip is pressed using a heater tool or the like. A method of mounting a semiconductor device in which a circuit board and a semiconductor chip are joined by heating and a semiconductor chip is simultaneously sealed is shown.

Further, Japanese Patent Application Laid-Open No. 6-89914 discloses that
A thermoplastic resin is applied to the center of the semiconductor chip with a nozzle and temporarily cured, and then pressed in a direction in which the electrodes of the semiconductor chip and the electrodes of the circuit board are in contact with each other. A sealing method of a semiconductor device in which a semiconductor chip and a circuit board are electrically connected by diffusing and sealing from a central portion to a periphery is shown.

However, in both the above-mentioned Japanese Patent Application Laid-Open No. 58-73126 and Japanese Patent Application Laid-Open No. Hei 6-89914, when a resin is applied in a hemispherical shape in a convex shape and a circuit board and a semiconductor chip are joined together, Is flowed to the periphery to suppress the generation of voids, and a resin is applied to the circuit board or the semiconductor chip using a nozzle. Many resins that can be applied using a nozzle are liquid at room temperature. In general, resin compositions that are liquid at room temperature often have a resin composition that is inferior in hydrolysis resistance, and in order to be liquid at room temperature, there is also a limitation on the amount of filler added,
The resin composition has a large coefficient of thermal expansion. When the coefficient of thermal expansion is large, the difference between the coefficient of thermal expansion between the semiconductor chip and the resin composition, and between the wiring board and the resin composition is large, and during the heat cycle, the interface between the semiconductor chip and the resin composition and between the wiring board and the resin The stress generated at the interface with the composition is large, and there is a possibility that interface delamination may occur, leading to defects such as bump cracks and poor conduction.

[0008]

The conventional semiconductor device using the above-described underfill resin has a complicated process because it is necessary to inject a sealing resin into a gap between a semiconductor chip and a wiring board. There's a problem. Furthermore, in order to avoid the occurrence of an uninjected portion with respect to the sealing resin,
It is required to increase the fluidity of the resin, and there is a limit to increasing the amount of the filler. If the amount of the filler is small, the thermal expansion coefficient of the resin composition becomes large, and the thermal stress between the resin composition layer and the semiconductor chip or the substrate becomes large, so that a defect such as a heat cycle test may occur. There is a problem that is high.

In the prior art in which a resin composition is interposed in advance between a semiconductor chip and a wiring board and then the semiconductor chip and the wiring board are electrically joined, any method for suppressing the generation of voids is required. It is necessary to apply a resin using a nozzle, and such a resin composition that is liquid at room temperature has a limit to increasing the amount of filler,
The resin composition has a large coefficient of thermal expansion. Therefore,
There is a problem that thermal stress between the resin composition layer and the semiconductor chip or the substrate is large, and there is a high possibility that a defect occurs in a test such as a heat cycle.

The present invention has been made in view of the above-mentioned problems of the prior art, and reduces the voids remaining in the resin composition layer, and furthermore, the thermal stress between the resin composition layer and the semiconductor chip or substrate. It is an object of the present invention to provide a method for connecting a circuit substrate such as a semiconductor chip or a wiring substrate with high reliability and a composite circuit substrate connecting the circuit substrates.

[0011]

According to a first method of the present invention, a method of connecting a circuit substrate comprises forming a first resin composition layer on a wiring surface of a first circuit substrate, and forming a first resin composition layer on a wiring surface of the first circuit substrate. A second resin composition layer having a lower melt viscosity than the first resin composition layer is formed on the composition layer or on the wiring surface of the second circuit substrate, and the wiring surfaces of the first and second circuit substrates are formed. The first and second circuit boards are opposed to each other with a bump electrode interposed therebetween, and the first and second circuit boards are joined with the resin composition, and the wiring between the circuit boards is electrically connected with the bump electrodes.

According to a second method of the present invention, in the first method, the circuit substrate is a semiconductor chip or a wiring board.

[0013] The method for connecting a circuit board according to a third method of the present invention is a method for connecting a circuit board after forming a first resin composition layer on a wiring surface of the first circuit board in the first or second method. And a second resin composition layer.

According to a fourth method of the present invention, in the third method, the surface of the second resin composition layer is formed in a hemispherical shape in the third method.

The method for connecting circuit boards according to a fifth method of the present invention is the method according to the third or fourth method, wherein the second resin composition layer uses a resin composition that is liquid at room temperature. is there.

According to a sixth aspect of the present invention, there is provided a method of connecting a circuit substrate according to the first or second aspect, wherein the second resin composition layer is laminated on the first resin composition layer. The film is attached to the wiring surface of the first circuit substrate.

According to a seventh aspect of the present invention, in the method for connecting a circuit substrate according to any one of the first to sixth aspects, the resin amount of the second resin composition layer is equal to the first resin composition. It is smaller than the resin amount of the material layer.

According to an eighth method of the present invention, in the method for connecting a circuit substrate according to any one of the first to seventh methods, the first and second resin composition layers may have a melting point higher than the melting point of the bump electrode. It melts at low temperatures.

According to a ninth method of the present invention, in any one of the first to eighth methods, the first or second resin composition layer contains an epoxy resin. .

According to a tenth method of the present invention, there is provided a method of connecting a circuit substrate according to any one of the first to eighth methods, wherein the first or second resin composition layer comprises an epoxy resin and a phenol cured resin. It contains an agent.

According to an eleventh method of the present invention, in any one of the first to tenth methods, the first or second resin composition layer contains a filler. .

According to a twelfth method of the present invention, in any one of the first to eleventh methods, bump electrodes are formed on both the first and second circuit substrates. Things.

The composite circuit board according to the first configuration of the present invention is manufactured by using the circuit board connecting method according to any one of the first to twelfth aspects.

The composite circuit substrate according to the second aspect of the present invention is a composite circuit substrate in which opposing circuit substrates are joined with a resin composition and wiring between the circuit substrates is electrically connected by bump electrodes. A circuit substrate, wherein the resin composition is a plurality of types of resin compositions having different melt viscosities.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A circuit substrate according to the present invention is a semiconductor chip or a wiring board on which a wiring circuit is formed. As a combination of two circuit substrates according to the present invention,
(A) a semiconductor chip and a semiconductor chip, (b) a semiconductor chip and a wiring board, and (c) a wiring board and a wiring board. The composite circuit substrate manufactured by the combination of (a) can be used as a semiconductor device by mounting it on a lead frame, a wiring board, or the like. The composite circuit substrate produced by the combination (b) is a semiconductor device itself, and the circuit substrate produced by the combination (c) is a multilayer wiring substrate.

Embodiment 1 A method of connecting a circuit substrate according to Embodiment 1 of the present invention will be described with reference to FIG. In the figure, reference numeral 1 denotes a first circuit substrate, which is a wiring substrate in the present embodiment. 2,
Reference numeral 6 denotes a bump electrode, and reference numeral 3 denotes a resin composition layer, which comprises a first resin composition layer 31 and a second resin composition layer 32 having a lower melt viscosity than this. 4 is a heating stage. 5 is the second
And a semiconductor chip in the present embodiment. 7, a heating head; and 8, an external bump electrode.

In the connection method, first, the bump electrodes 2 are formed on the wiring board 1 (step (ii)). Next, after forming the first resin composition layer 31 on the wiring substrate 1 on which the bump electrodes 2 are formed (step (iii) -1), the first resin composition layer 31 is formed on the first resin composition layer 31. Forming a second resin composition layer 32 having a lower melt viscosity than the composition layer 31 (step (iii));
2).

Next, the wiring board 1 on which the resin composition layer 3 is formed is positioned on a heating stage 4 which is set at a predetermined temperature, that is, lower than the melting point of the bump electrodes 2 and 6 and higher than the melting point of the resin composition layer 3. (Step (iv)). Further, the semiconductor chip 5 on which the bump electrodes 6 are formed is positioned and fixed on the heating head 7. Since the heating stage 4 is heated to a predetermined temperature, that is, a temperature lower than the melting point of the bump electrodes 2 and 6 and higher than the melting point of the resin composition layer 3, the resin composition layer 3 formed on the wiring board 1 is in a molten state. Has become.

Next, the heating head 7 is moved to bring the bump electrodes 6 of the semiconductor chip 5 fixed to the heating head 7 into contact with the bump electrodes 2 of the wiring board 1 fixed to the heating stage 4. Further, while keeping the distance between the semiconductor chip 5 and the wiring board 1 constant so that the bump electrodes 2 and 6 keep the contact state, the heating head 7 is heated at a predetermined profile to increase the bump electrodes 2 and 6 and the resin. The composition layer 3 is heated to the extent that the resin composition layer 3 does not gel, so that the resin composition layer 3 and the bump electrodes 2 and 6 are both in a molten state to electrically connect the wiring board 1 and the semiconductor chip 5 ( Step (v)). In this case, the second resin composition layer 32 having a lower melt viscosity of the upper layer
Are used to flatten irregularities generated on the surface of the resin composition layer 3, and most are pushed out together with voids remaining when the semiconductor chip 5 is joined to the wiring board 1, and a part is extruded. Remains in 3. The gelation of the resin means that the resin does not show fluidity due to the reaction. However, the gelation time (also related to the temperature) of the resin composition used in the present invention is not particularly limited, but the process during the production may differ depending on the gelation time of the resin. The process when the gelation time is short will be described in Examples 2 and 3 described later.

Next, while keeping the distance between the wiring board 1 and the semiconductor chip 5 constant, the temperature of the heating head 7 is lowered according to a predetermined profile, and the wiring board 1, the semiconductor chip 5, the bump electrodes 2, 6, and the resin composition are formed. The material layer 3 is cooled to a temperature lower than the melting points of the bump electrodes 2 and 6 and the resin composition layer 3. Both the resin composition layer 3 and the bump electrodes 2 and 6 solidify.

Next, the resin composition layer 3 is cured in an oven in which the joined composite circuit substrate, that is, the semiconductor device, is set at a predetermined temperature at which the melting point of the bump electrodes 2 and 6 is lower than the melting point and the resin composition layer 3 can be cured. After a predetermined time, the resin composition layer 3 is cured (step (vi)). Further, after the resin composition layer 3 is cured, the external bump electrodes 8 can be formed on the wiring board 1 (step (vii)).

According to the connection method as described above, it is possible to reduce the time and the number of steps compared with the conventional underfill method in which a resin is poured into a narrow gap, and it is difficult to use the underfill method. The formation of the resin composition layer 3 in advance is possible even for an ultra-narrow gap.

Further, in the resin composition layer 3, the melt viscosity of the upper second resin composition layer 32 is lower than that of the lower first resin composition layer 31. 5
The voids trapped during the bonding are discharged outside from between the first and second circuit substrates 1 and 5, so that no voids remain in the resin composition layer 3. Therefore, the bump electrodes 2
When the solder bumps 6 are formed of a solder material and the solder bumps are re-melted during mounting, there is no fear that the solder bumps flow out into the void space. Further, the problem that water accumulates in the void portion during moisture absorption and accelerates the corrosion of package cracks and the corrosion of the wiring material of the circuit substrate during reflow can be reduced.

Further, in the conventional method for reducing the generation of voids, the resin composition is applied to the central portion of the circuit substrate with a nozzle or the like, and the entire resin composition flows when it is joined to another circuit substrate. Reduces the occurrence of voids,
The resin composition is required to have high fluidity characteristics, and the amount of the filler added is limited, so that the coefficient of thermal expansion is large, and the difference in the coefficient of thermal expansion with the circuit substrate is large. The second resin composition layer 32 only needs to flow at the time of joining,
In addition, since most of the second resin composition layer 32 flows out at the time of joining, the resin composition layer 3 having a coefficient of thermal expansion close to the coefficient of thermal expansion of the circuit substrates 1 and 5 can be obtained.

Further, according to the above connection method,
Since the resin composition layer 3 is brought into contact with the solid bumps 2 and 6 in a molten state, the bumps 2 and 6 can be joined without the resin composition being bitten between the bumps 2 and 6, and the composite circuit substrate has high electrical connection reliability. Is obtained. Further, when the bumps 2 and 6 are melted to electrically connect the first and second circuit substrates 1 and 5, the surrounding resin composition is also melted. The bumps 2 and 6 can be formed in an optimum joint shape without being restrained, so that a composite circuit substrate having high reliability of electrical connection can be obtained. Further, since the first and second circuit substrates 1 and 5 are always kept at a constant interval, even if the resin composition layer 3 and the bumps 2 and 6 are melted and liquefied, the first and second circuit substrates 1 and 5 are liquefied. Since there is no loss from the space between the substrates 1 and 5, the reliability of bonding is improved.

The material of the bump electrodes 2 and 6 that can be used in the present embodiment is not particularly limited as long as electrical conductivity can be ensured. As a material for the solder bump electrode, a tin-lead eutectic solder (63% by weight of tin, melting point: 183 ° C.) is easy to use on the process side and has high reliability. Also, since it does not contain lead, it is possible to reduce the burden on the environment, so tin-silver, tin-copper,
A tin-zinc system, a tin-bismuth system, and any solder material obtained by further adding bismuth, copper or bismuth and copper to these systems can be applied in the present embodiment. Also, materials other than solder can be used as the material of the bump electrodes 2 and 6, for example, gold and the like can be used.

As a method for forming the bump electrodes 2 and 6 on the circuit substrates 1 and 5, any method such as a heat-melt transfer method, a vapor deposition method, a plating method, a wire bonding method, a printing method, and a ball mounting method is used in the present embodiment. Applicable in form. Further, the molten solder is jetted using the principle of the ink jet printer method, and the bump electrodes 2 and 2 are jetted.
6 can also be applied in the present embodiment.

In this embodiment, if the melt viscosity of the second resin composition layer 32 in the upper layer is lower than the melt viscosity of the first resin composition layer 31 in the lower layer, The resin composition is not limited, and any of a thermosetting resin and a thermoplastic resin composition can be used. However,
When a thermoplastic resin composition is used, the step of curing the resin composition by heating (step (vi)) is unnecessary. Also,
The melt viscosity of the uppermost resin composition (second resin composition layer) is not necessarily required to be a two-layer structure, and even in a multilayer structure of three or more layers, the lower layer resin composition (first resin composition) What is necessary is that it is lower than the melt viscosity of the resin composition layer).

The method for forming the resin composition layer 3 on the circuit substrates 1 and 5, that is, the method for forming the first resin composition layer 31 on the circuit substrates 1 and 5, and the method for forming the first resin composition layer 31 on the first resin composition layer 31 2
As a method for forming the resin composition layer 32, any method such as a printing method, a dispensing method, a stamping method, a casting method, a spin coating method, and a curtain coating method can be applied in the present embodiment. Further, it may be formed while heating.

Incidentally, the first and second resin compositions 31,
After the printing and application of 32, heating under reduced pressure can be performed to remove air remaining around the bump electrode 2 and volatile components in the resin composition. Furthermore, when the first and second resin composition layers 31 and 32 are formed in a reduced-pressure atmosphere, it is possible to form the resin composition layer 3 by suppressing generation of voids.

As the liquid resin composition, a resin composition containing a solvent is also applicable in the present embodiment. After application to the circuit substrates 1 and 5, the solvent is volatilized to form the resin composition layer 3. The solvent is not particularly limited as long as it dissolves other than the inorganic material in the resin composition.For example, solvents such as dimethyl sulfoxide, dimethylformamide, methylene chloride, chloroform, methyl ethyl ketone, acetone, tetrahydrofuran, and ethyl acetate A single solvent or a mixed solvent thereof can be used. In particular,
A single or mixed solvent which can be volatilized at 80 to 150 ° C. is preferable, and methyl ethyl ketone or a mixed solvent thereof is preferable because it can be dried at 80 to 100 ° C. and can dissolve the resin composition.

First and second resin composition layers 31 and 32
At least one of them has been used in the semiconductor field, and preferably contains an epoxy resin since it imparts adhesiveness to the resin composition. The epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD type Epoxy resin, diallyl bisphenol A type epoxy resin, diallyl bisphenol F type epoxy resin, diallyl bisphenol AD type epoxy resin, tetramethyl biphenol type epoxy resin, biphenol type epoxy resin, cyclopentadiene type epoxy resin, terpene phenol type epoxy resin, tetrabromo Bisphenol A type epoxy resin, phenol novolak type epoxy resin, cresol novolak type epoxy resin, triphenylmethane type epoxy resin, cycloaliphatic epoxy resin, Glycidyl ester epoxy resins, and heterocyclic epoxy resins and the like, alone or a mixture thereof. Among the above epoxy resins, bisphenol A epoxy resin, bisphenol F epoxy resin, cycloaliphatic epoxy resin and glycidyl ester epoxy resin are liquid resins at room temperature.

The first and second resin composition layers 3
For at least one of 1, 32, it is preferable to use a phenol resin which has been used in the field of semiconductors requiring high reliability without worrying about hydrolyzability as a curing agent for epoxy resin. Phenol resins include phenol novolak, cresol novolak, xylesol novolak, bisphenol A novolak, bisphenol F
Novolak, bisphenol AD novolak, bisphenol A, bisphenol F, bisphenol A
D, diallyl bisphenol A, diallyl bisphenol F, and diallyl bisphenol AD, and the like, or a mixture thereof is used.

The first and second resin composition layers 3
It is preferable that at least one of 1 and 32 contains a filler in order to reduce the coefficient of thermal expansion or to impart low water absorption. Examples of the filler include silica such as fused silica and crystalline silica, alumina, silicon nitride, calcium carbonate, zinc oxide and the like. Above all, it is preferable to use fused silica from the viewpoint of reducing the coefficient of thermal expansion of the obtained resin composition and improving the mechanical strength. Further, spherical fused silica is preferred from the viewpoint of imparting fluidity.

The device used to electrically connect the wiring between the circuit substrates 1 and 5 with the bump electrodes 2 and 6 is not particularly limited. However, from the viewpoints of positioning accuracy and temperature raising / lowering functions, a flip chip bonder is used. Is preferably used in the present embodiment, for example, a commercially available flip chip bonder CB-1
750 (manufactured by Miss FA Corporation) and the like can be used.

When joining the first circuit substrate 1 and the second circuit substrate 5 with a flip chip bonder, if the resin composition layer 3 is solid, the bump electrodes 2 and 6 are brought into contact with each other to conduct electricity. It is necessary to apply a large weight to the circuit substrates 1 and 5 to secure the circuit board 1 and 5, and damage of the circuit substrates 1 and 5 and the bump electrodes 2 and
Since the shape of No. 6 is bad and the contact state is unstable, problems such as a decrease in reliability occur. Further, in a state where both the bump electrodes 2 and 6 and the resin composition layer 3 are molten, it is difficult to make sure that the bump electrodes 2 and 6 formed on the circuit substrates 1 and 5 are in contact with each other. Reliability decreases. On the other hand, when the resin composition layer 3 is in a molten state and the bump electrodes 2 and 6 are in a solid state, the bump electrodes 2 and 6 formed on the circuit substrates 1 and 5 can be easily brought into contact with each other. It is preferable because it becomes possible.

For the above reasons, the first and second circuit substrates 1
When joining between 5 and 5, the resin composition layer 3 is
It is preferable that the resin be melted at a temperature lower than the melting point of No.6. When a tin-lead (eutectic 63% by weight) eutectic solder is used as the bump electrodes 2 and 6, the melting point is 183 ° C. It is preferable that the composition layer 3 is melted before being heated to 183 ° C. In this case, there is no problem even if it is liquid at room temperature.

It is preferable that the resin amount of the uppermost second resin composition layer 32 having a lower melt viscosity is smaller than the resin amount of the lower first resin composition layer 31. In this case, the uppermost second resin composition layer 32 is
It is used to compensate for unevenness that occurs in
Most of the resin is preferably pushed out together with the confined void when the two circuit substrates 1 and 5 are joined. Therefore, the amount of resin in the uppermost second resin composition layer 32 is preferably smaller than the amount of resin in the lower second resin composition layer 32, and the amount of resin in the second resin composition layer 32 is preferably smaller. Is 50% of the resin amount of the first resin composition layer 31
The following (volume ratio) is preferable. Furthermore, if the lower first resin composition layer 31 has a thickness corresponding to the gap between the circuit substrates 1 and 5 which is originally intended, the amount of resin in the uppermost second resin composition layer 32 is the first. Resin composition layer 3
It is preferably 30% or less (volume ratio) with respect to the amount of the resin (1).

In this embodiment, the bump electrodes 2 and
6 is formed on both the first and second circuit substrates 1 and 5, and the circuit substrates 1 and 5 are warped or undulated, and each bump electrode 2 is formed.
This is preferable because variations in height 6 can be buffered and electrical connection can be performed more reliably.

Further, in the above embodiment, the case where the second resin composition layer 32 is formed on the first resin composition layer 31 has been described, but the second resin composition layer 32 is formed on the wiring surface of the second circuit substrate 5. It may be formed, and the same effect as in the above embodiment can be obtained.

Embodiment 2 FIG. 2 is an explanatory view showing a method of connecting circuit substrates according to a second embodiment of the present invention in the order of steps. In the present embodiment, the second resin composition layer 32 is
It is the same as that of the first embodiment, except that it is applied using a dispensing method or the like (step (iii) -2) so that the central portion is high and the surface shape is hemispherical on the resin composition layer 31 of (1). . In the present embodiment, it is preferable that the second resin composition layer 32 be liquid at room temperature because it can be easily applied by a dispensing method or the like.

According to the present embodiment, the second resin composition layer 32 is formed so that its central portion is high and its surface shape is hemispherical.
By flowing the resin composition in the vicinity, the generation of voids can be effectively suppressed.

Although the second embodiment has described the case where the second resin composition layer 32 is formed on the first resin composition layer 31, the second resin composition layer 32 is formed on the wiring surface of the second circuit substrate 5. The same effect as in the second embodiment can be obtained.

Embodiment 3 FIG. FIG. 3 is an explanatory view showing a method of connecting circuit substrates according to a third embodiment of the present invention in the order of steps. In the present embodiment, a film-shaped resin composition having a configuration in which a second resin composition layer 32 having a lower melt viscosity is laminated on a first resin composition layer 31 is applied to the first circuit substrate 1. Except that the resin composition layer 3 was formed by sticking to the wiring surface,
This is the same as the first embodiment. The attachment of the film-shaped resin composition can be performed by pressing the film-shaped resin composition onto the wiring board 1 using a laminator, a hot press, or the like. Note that the same material as that described in Embodiment 1 can be used as the material of the resin composition in the form of a film.

In the drawings, the case where a film-shaped resin composition having a two-layer structure is used has been described. However, it is not always necessary to have two layers, and the second resin composition having the lowest melt viscosity is provided on the uppermost layer. It is also possible to use three or more layers using the material layer 32 or an inclined type film in which the melt viscosity gradually decreases from the lower layer to the upper layer. In addition,
After the film is attached to the circuit substrate 1, the film is heated to a temperature at which the resin compositions 31 and 32 are melted in order to remove voids remaining in the uneven portions of the circuit substrate 1 and voids remaining in the resin composition layer 3. By reducing the pressure, residual voids can be prevented.

According to the present embodiment, since the resin composition is a film, handling is easy and production efficiency can be improved.

In the third embodiment, the case where the second resin composition layer 32 is formed on the first resin composition layer 31 has been described. The same effect as in the third embodiment can be obtained.

Embodiment 4 FIG. 4 is an explanatory view showing a method of connecting circuit substrates according to a fourth embodiment of the present invention in the order of steps. Except for forming the resin composition layer 3 on one circuit substrate 1 (step (iii) -1, 2 and step (iv)) and forming the bump electrode 6 on the other circuit substrate 2 (step (v)). This is the same as in the second embodiment. Note that the present invention is not limited to the second embodiment, and may be the same as the first and third embodiments.

According to the present embodiment, since the resin composition layer 3 can be formed on the flat first circuit substrate 1 without the bump electrode 2, it can be formed uniformly without voids and the reliability can be improved. It becomes possible.

Although the fourth embodiment has described the case where the second resin composition layer 32 is formed on the first resin composition layer 31, the second resin composition layer 32 on which the bump electrode 6 is formed is formed. The second resin composition layer 32 may also be formed on the wiring surface of the circuit substrate 5, and in this case also, most of the second resin composition layer 32 is pushed out together with the voids remaining at the time of bonding. Even if voids are formed between the material layers 32, the voids can be removed or the irregularities on the surface of the first resin composition layer 31 can be flattened, thereby improving the effect of reducing voids as in the fourth embodiment. Can be achieved.

Embodiment 5 FIG. 5 is an explanatory view showing a method of connecting circuit substrates according to a fifth embodiment of the present invention in the order of steps. A bump electrode 2 and a resin composition layer 3
(Step (ii), step (iii) -1,
2 and step (iv)), except that neither the bump electrode nor the resin composition layer was formed on the other circuit substrate 2. Note that the present invention is not limited to the second embodiment, and may be the same as the first and third embodiments.

According to the present embodiment, since both the bump 2 and the resin composition layer 3 are formed on only one circuit substrate 1, both circuit substrates 1 and 5 are formed as in the first to third embodiments.
And the resin composition layer 3 on one circuit substrate 1.
Respectively, or in a case where the resin composition layer 3 is formed on one circuit substrate 1 and the bump electrode 6 is formed on the other circuit substrate 5 as in the fourth embodiment, respectively. Production efficiency is improved.

In the first, second, fourth and fifth embodiments,
In the above, a second resin composition layer 32 may be formed by a method such as printing or dispensing after a film is used as the first resin composition layer 31 and attached to the wiring substrate 1. When the first resin composition layer 31 is formed on the first circuit substrate 1 and the second resin composition layer 32 is formed on the second circuit substrate 5, the first and second resin composition layers 32 are formed.
Both the resin composition layers 31 and 32 may be in the form of a film. In these cases, in addition to the effects of the respective embodiments, an effect of facilitating handling is obtained because the resin composition is in the form of a film.

In each of the above embodiments, the case where the first circuit substrate 1 is a wiring substrate and the second circuit substrate 5 is a semiconductor chip has been described. Needless to say, this is obtained. In addition, the first and second circuit substrates 1 and 5 may both be semiconductor chips, or both may be wiring substrates. In this case, the same effect can be obtained.

[0065]

EXAMPLES Specific examples are shown below, but the present invention is not limited to these examples. Each of the following examples,
The case where the first circuit substrate 1 is a wiring substrate and the second circuit substrate 5 is a semiconductor chip is shown. In each example, the bump electrode material formed on at least one of the semiconductor chip 5 and the wiring board 1 and the resin composition layer 3 formed on the wiring board 1 were combined in the combinations shown in Table 1.
Moreover, the resin composition used in each Example used the material shown in Table 2. The gelation time is a value measured on a hot plate set at a predetermined temperature in advance. Table 2
The middle, lower and upper layers are the first and second resin composition layers 31 and 32, respectively.

[0066]

[Table 1]

[0067]

[Table 2]

Embodiment 1 Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate.

First, a eutectic solder bump electrode 2 of tin-lead (63% by weight of tin) is formed on a wiring board 1,
The wiring substrate 1 with the bump electrodes 2 was manufactured (step (i)
i)). Next, the resin composition (A) in the form of a two-layer film is heated and pressed (80 ° C., 10 seconds,
0.1 kgf / mm ² ) to form a resin composition layer 3 (step (iii)). Next, on the flip chip bonder, the wiring substrate 1 on which the resin composition layer 3 was formed was positioned and fixed on the heating stage 4 set at a predetermined temperature (150 ° C.) (step (iv)). Further, the semiconductor chip 5 with the bump electrode 6 was positioned and fixed on the heating head 7 (150 ° C.). According to Table 2, the melting temperature of the resin composition (A) was 8
0 ° C. and the heating stage 4 is at a higher temperature (15 ° C.).
(0 ° C.), the resin composition layer 3 formed on the wiring board 1 is in a molten state.

Next, the heating head 7 was moved to bring the bump electrodes 6 of the semiconductor chip 5 fixed to the heating head 7 into contact with the bump electrodes 2 on the wiring board 1 fixed to the heating stage 4. Next, the distance between the semiconductor chip 5 and the wiring board 1 is kept constant (90 μm) while the bump electrodes 2 and 6 are in contact with each other.
After the temperature of the heating head 7 was raised to 230 ° C. in 5 seconds while maintaining the temperature in m), the temperature was maintained at 230 ° C. for 10 seconds to heat the bump electrodes 2 and 6 and the resin composition layer 3. The bump electrodes 2 and 6 and the resin composition layer 3 were both in a molten state, and the wiring board 1 and the semiconductor chip 5 were electrically connected via the bump electrodes 2 and 6 (step (v)). In this case, the upper resin composition layer 32 having a low melt viscosity is the resin composition layer 3
Mostly, the semiconductor chip 5 was pushed out together with the remaining voids when the semiconductor chip 5 was bonded to the wiring board 1, and a part thereof was left in the resin composition layer 3. Next, the distance between the wiring board 1 and the semiconductor chip 5 is fixed (90
While maintaining the temperature, the heating head 7 was cooled down with a predetermined profile to cool the wiring board 1, the semiconductor chip 5, the bump electrodes 2, 6, and the resin composition layer 3 to 100 ° C. Then, the bump electrodes 2 and 6 were solidified, and then taken out from the flip chip bonder and left at room temperature to solidify the resin composition layer 3.

Next, the bonded wiring board 1 and semiconductor chip 5 are left in an oven set at 170 ° C. lower than the melting temperature of the bump electrodes 2 and 6 (183 ° C.) for 2 hours.
The resin composition layer 3 was cured (step (vi)). Finally, an external bump electrode 8 was formed on the wiring board 1 to obtain a semiconductor device (step (vii)).

Embodiment 2 FIG. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate.

First, a eutectic solder bump electrode 2 of tin-lead (63% by weight of tin) was formed on the wiring board 1 in the same manner as in Example 1 (step (ii)). Next, the resin composition (B) in the form of a two-layer film was heated and pressed (80 ° C., 10 seconds, 0.1 kgf / mm ² ) on the wiring substrate 1 to form the resin composition layer 3 (step). (Iii)). Next, on the flip chip bonder, the wiring board 1 on which the resin composition layer 3 was formed was positioned and fixed on the heating stage 4 set at a predetermined temperature (80 ° C.) (step (iv)). Further, the semiconductor chip 5 with the bump electrode 6 is moved to the heating head 7 (150
° C) and fixed. According to Table 2, the melting temperature of the resin composition (B) was 80 ° C.
Since the substrate is heated to 0 ° C., the resin composition layer 3 formed on the wiring board 1 is in a molten state.

Next, the heating head 7 is moved to apply a constant pressure (15 kgf / chip) between the bump electrode 6 of the semiconductor chip 5 fixed to the heating head 7 and the bump electrode 2 on the wiring board 1 fixed to the heating stage 4. In addition, they were brought into contact and kept in this state for 60 seconds. According to Table 2, the gel time of the resin composition layer 3 is 30 seconds at 150 ° C., and during this time, the eutectic solder bumps 2 and 6 of both the wiring board 1 and the semiconductor chip 5 are kept in contact with each other. Layer 3 gelled (step (v)). In this case, the upper second resin composition layer 32 having a low melt viscosity is used for flattening irregularities generated in the resin composition layer 3, and most of the second resin composition layer 32 is used when the semiconductor chip 5 is bonded to the wiring board 1. It was extruded out together with the remaining voids, and a part thereof remained in the resin composition layer 3. Next, the temperature of the heating head 7 is lowered with a predetermined profile, and the wiring board 1, the semiconductor chip 5, the bump electrodes 2, 6, and the resin composition
Cooled to 0 ° C.

Next, the bonded wiring board 1 and the semiconductor chip 5 are heated at 150 ° C. lower than the melting temperature of the bump electrodes 2 and 6.
Was left in the oven set for 1 hour to cure the resin composition layer 3 (step (vi)).

Finally, external bump electrodes 8 were formed on the wiring board 1 to obtain a semiconductor device (step (vii)). In addition,
Since the semiconductor device is exposed to a temperature range higher than the melting point of solder when forming the external bump electrodes 8 on the wiring board 1, the bump electrodes 2, 6 between the wiring board 1 and the semiconductor chip 5 are exposed.
Was melted, and electrical continuity could be secured in a state where the bump electrodes 2 and 6 were metal-bonded.

Embodiment 3 FIG. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate.

In the connection method, first, the gold bump electrode 2 was formed on the wiring substrate 1 (step (ii)). Next, the resin composition (B) in the form of a two-layer film was heated and pressed (80 ° C., 10 seconds, 0.1 kgf / mm ² ) on the wiring substrate 1 to form the resin composition layer 3 (step). (Iii)). next,
The wiring substrate 1 on which the resin composition layer 3 was formed on the flip chip bonder was positioned and fixed on the heating stage 4 set at a predetermined temperature (80 ° C.) (step (iv)). Further, the semiconductor chip 5 with the bump electrode 6 is moved to the heating head 7 (150
° C) and fixed.

Next, the heating head 7 is moved to apply a constant pressure (15 kgf / chip) between the bump electrode 6 of the semiconductor chip 5 fixed to the heating head 7 and the bump electrode 2 on the wiring board 1 fixed to the heating stage 4. In addition, they were brought into contact and kept in this state for 60 seconds. According to Table 2, the gel time of the resin composition layer 3 is 30 seconds at 150 ° C., so that the gold bumps 2 and 6 of both the wiring board 1 and the semiconductor chip 5 are kept in contact during this time. 3 was gelled (step (v)). In this case, the upper second resin composition layer 32 having a low melt viscosity is used for flattening irregularities generated in the resin composition layer 3, and most of the second resin composition layer 32 is used when the semiconductor chip 5 is bonded to the wiring board 1. The resin was extruded out together with the remaining voids, and a part thereof remained in the resin composition layer 3. Next, the temperature of the heating head 7 is lowered with a predetermined profile to remove the wiring board 1, the semiconductor chip 5, the bump electrodes 2, 6, and the resin composition layer 3 by 100.
Cooled to ° C.

Next, the bonded wiring board 1 and the semiconductor chip 5 are heated at 150 ° C. lower than the melting temperature of the bump electrodes 2 and 6.
Was left in the oven set for 1 hour to cure the resin composition layer 3 (step (vi)). Finally, an external bump electrode 8 was formed on the wiring board 1 to obtain a semiconductor device (step (vii)). In this embodiment, the bump electrodes 2, 6
Since gold having a melting point of 1000 ° C. or more was used, no melting occurred during the formation of the external bump electrode 8 as in Example 2.

Embodiment 4 FIG. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate.

The connection method is as follows. First, a eutectic solder bump electrode 2 of tin-lead (63% by weight of tin) is formed on a wiring board 1,
The wiring substrate 1 with the bump electrodes 2 was manufactured (step (i)
i)). Next, the resin composition (C) -1 is placed on the wiring board 1.
Is printed as a first resin composition layer 31 after heating (80 ° C.) (step (iii) -1), and further, a resin composition (C) -2
Was printed as a second resin composition layer 32 by heating (80 ° C.) to form a resin composition layer 3 (step (iii)).
2). Thereafter, in the same steps as in Example 1, heating, bonding,
The semiconductor device was obtained by curing the resin and forming the eight external bump electrodes.

Embodiment 5 FIG. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate.

The connection method is as follows. First, a eutectic solder bump electrode 2 of tin-lead (63% by weight of tin) is formed on a wiring board 1,
The wiring substrate 1 with the bump electrodes 2 was manufactured (step (i)
i)). Next, a film-shaped resin composition (D) -1 is applied as a first resin composition layer 31 on the wiring board 1 by applying heat and pressure (80 ° C., 10 seconds, 0.1 kgf / mm ² ). (Step (iii) -1), and further heating the resin composition (D) -2 as a second resin composition layer 32 thereon (80).
° C) to form a resin composition layer 3 (step (ii)
i) -2). Thereafter, in the same process as in Example 1, heating,
Bonding, resin curing, and formation of the external bump electrode 8 were performed to obtain a semiconductor device.

Embodiment 6 FIG. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate. In the connection method, first, a eutectic solder bump electrode 2 of a tin-lead system (63% by weight of tin) was formed on the wiring substrate 1, and the wiring substrate 1 with the bump electrode 2 was manufactured (step (ii)). Next, a film-shaped resin composition (E) -1 is applied as a first resin composition layer 31 on the wiring board 1 by applying heat and pressure (80 ° C., 10 seconds, 0.1 kgf / mm ² ). (Step (iii) -1), on which the resin composition (E) is formed as a second resin composition layer 32 by the dispenser 10.
-2 was dispensed such that the central portion was convex and the surface shape was hemispherical (step (iii) -2). Hereinafter, Example 1
In the same steps as those described above, heating, bonding, resin curing, and formation of the external bump electrode 8 were performed to obtain a semiconductor device.

Practical example 7. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate. The connection method is as follows. First, a gold bump electrode 2 is formed on a wiring substrate 1, and the wiring substrate 1 with the bump electrode 2 is formed.
Was prepared (step (ii)). Next, the film-shaped resin composition (F) -1 was heated and pressed (80 ° C., 10 seconds, 0.1 kg) on the wiring board 1 as a first resin composition layer 31.
f / mm ² ) and affixed (step (iii) -1), on which the dispenser 10 is formed as a second resin composition layer 32.
The resin composition (F) -2 was dispensed so that the central part was convex and the surface shape was hemispherical (step (iii)).
2). Thereafter, in the same steps as in Example 3, heating, bonding,
The resin was cured and the external bump electrodes 8 were formed to obtain a semiconductor device.

Embodiment 8 FIG. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate. In the connection method, first, a eutectic solder bump electrode 2 of a tin-lead system (63% by weight of tin) was formed on the wiring substrate 1, and the wiring substrate 1 with the bump electrode 2 was manufactured (step (ii)). Next, a resin composition (G) in the form of a gradient film, whose melt viscosity gradually decreases from the lower layer to the upper layer, is heated and pressed (80 ° C., 10 seconds, 0.1 kg) on the wiring board 1.
f / mm ² ) to form the resin composition layer 3 (step (iii)). Thereafter, in the same steps as in Example 1, heating, bonding, resin curing, and formation of the external bump electrode 8 were performed to obtain a semiconductor device.

Embodiment 9 FIG. Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate. The connection method is as follows. First, a film-shaped resin composition (E) -1 is formed on the wiring substrate 1 as a first resin composition layer 31 by heating and pressing (80 ° C., 10 seconds, 0.1 kgf).
/ Mm ² ) and affixed (step (iii) -1), on which the resin composition (E) -2 was formed as a second resin composition layer 32 by the dispenser 10 so that the central part was convex and the surface shape was convex. Dispensed into a hemispherical shape (step (iii))
2). Thereafter, in the same steps as in Example 1, heating, bonding,
The resin was cured and the external bump electrodes 8 were formed to obtain a semiconductor device.

Embodiment 10 FIG. By connecting the wiring board 1 and the semiconductor chip 5 according to the process of FIG. 5, a semiconductor device as a composite circuit base was manufactured. In the connection method, first, a eutectic solder bump electrode 2 of a tin-lead system (63% by weight of tin) was formed on the wiring substrate 1, and the wiring substrate 1 with the bump electrode 2 was manufactured (step (ii)). Next, a resin composition (E) is
-1 as a first resin composition layer 31 after heating (80 ° C.) printing (step (iii) -1), and further thereon a resin composition (E) -2 as a second resin composition layer 32 Heat printing was performed to form a resin composition layer 3 (step (iii))
2).

Next, the wiring board 1 on which the resin composition layer 3 was formed on the flip chip bonder was positioned and fixed on the heating stage 4 set at a predetermined temperature (150 ° C.) (step (iv)). The semiconductor chip 5 is connected to the heating head 7 (1
(50 ° C.) and fixed. From Table 2, the resin composition (E) -1 is liquid at room temperature, the melting temperature of the resin composition (E) -2 is 80 ° C., and the wiring board 1 is heated because the heating stage 4 is heated to 150 ° C. Resin composition layer 3 formed on
Is in a molten state.

Thereafter, bonding and bonding are performed in the same steps as in the first embodiment.
The resin was cured and the external bump electrodes 8 were formed to obtain a semiconductor device.

Embodiment 11 FIG. According to the process of FIG. 3, the wiring substrate 1 and the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate. In the connection method, first, the gold bump electrodes 2 were formed on the wiring substrate 1, and the wiring substrate 1 with the bump electrodes 2 was manufactured (step (ii)). Next, the resin composition (H) in the form of a two-layer film is heated and pressurized (80
C., 10 seconds, 0.1 kgf / mm ² ) to form a resin composition layer 3 (step (iii)). Next, the wiring board 1 on which the resin composition layer 3 was formed on the flip chip bonder was positioned and fixed on the heating stage 4 set at a predetermined temperature (180 ° C.) (step (iv)). Also, the bump electrode 6
The attached semiconductor chip 5 was positioned and fixed to the heating head 7 (180 ° C.). From Table 2, the melting temperature of the resin composition (H) is 150 ° C.
Since the substrate is heated to 80 ° C., the resin composition layer 3 formed on the wiring board 1 is in a molten state.

Next, the heating head 7 is moved, and the bump electrode 6 of the semiconductor chip 5 fixed to the heating head 7 and the bump electrode 2 on the wiring board 1 fixed to the heating stage 4 are applied with a constant pressure (15 kgf / chip). In addition, contact was made. The gold bumps 2 and 6 of both the wiring board 1 and the semiconductor chip 5 were in contact (step (v)). At this time, the second resin composition layer 32 having a low melt viscosity is used to flatten the unevenness generated in the resin composition layer 3, and most of the second resin composition layer 32 is pushed out when the semiconductor chip 5 is joined to the wiring board 1. And a part remains in the resin composition layer 3. Next, the temperature of the heating head 7 is lowered according to a predetermined profile, and the wiring substrate 1, the semiconductor chip 5, the bump electrodes 2, 6,
And the resin composition layer 3 was cooled to 100 degreeC. Then, the molten resin composition layer 3 was solidified. Finally, external electrodes 8 were formed on the wiring substrate 1 to obtain a semiconductor device (step (vii)).

Comparative Example 1 FIG. 6 is an explanatory view showing a method of connecting circuit substrates according to Comparative Example 1 in the order of steps. By connecting the wiring board 1 and the semiconductor chip 5 according to the process of FIG. 6, a semiconductor device as a composite circuit base was manufactured.

The connection method is as follows. First, a eutectic solder bump electrode 2 of tin-lead (63% by weight of tin) is formed on a wiring board 1,
The wiring substrate 1 with the bump electrodes 2 was manufactured (step (i)
i)). Next, the resin composition (I) in the form of a single-layer film is heated and pressed (80 ° C., 10 seconds, 0.1 kg) on the wiring board 1.
f / mm ² ) and affixed to form a resin composition layer 3 on the wiring board 1 (step (iii)). Thereafter, in the same steps as in Example 1, heating, bonding, resin curing, and formation of the external bump electrode 8 were performed to obtain a semiconductor device.

Comparative Example 2 Wiring board 1 according to the process of FIG.
And the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate.

[0097] In the connection method, first, the gold bump electrodes 2 were formed on the wiring substrate 1, and the wiring substrate 1 with the bump electrodes 2 was manufactured (step (ii)). Next, the film-shaped resin composition (J) is heated and pressed (80 ° C., 10 seconds,
0.1 kgf / mm ² ) and affixed to form a resin composition layer 3 on the wiring board 1 (step (iii)). Since then
In the same steps as in Example 3, heating, bonding, resin curing, and formation of external bump electrodes 8 were performed to obtain a semiconductor device.

Comparative Example 3 FIG. 7 is an explanatory view showing a method of connecting circuit substrates according to Comparative Example 3 in the order of steps. According to the process of FIG. 7, the wiring board 1 and the semiconductor chip 5 were connected to manufacture a semiconductor device as a composite circuit substrate.

The connection method is as follows. First, a eutectic solder bump electrode 2 of tin-lead (63% by weight of tin) is formed on a wiring board 1,
The wiring substrate 1 with the bump electrodes 2 was manufactured (step (i)
i)).

Next, the dispenser 1 is placed on the wiring board 1.
At 0, the resin composition (K) was dispensed so that the central portion was convex and the surface shape was hemispherical (step (iii)). Thereafter, in the same steps as in Example 1, heating, bonding, resin curing, and formation of the external bump electrode 8 were performed to obtain a semiconductor device.

In order to confirm the voids present in the resin composition layers 3 of the semiconductor devices manufactured in Examples 1 to 11 and Comparative Examples 1 to 3, observations were made with an ultrasonic microscope and section polishing. Table 3 shows the results of the observation.

[0102]

[Table 3]

From Table 3, no voids were observed in the resin composition layer 3 of the semiconductor devices manufactured based on Examples 1 to 11. On the other hand, although no void was observed in the resin composition layer 3 of the semiconductor device manufactured based on Comparative Example 3, the resin composition layer 3 of the semiconductor device manufactured based on Comparative Examples 1 and 2 did not. When the semiconductor chip 5 and the wiring substrate 1 were joined, an air layer (void) which was considered to be trapped was observed.

Next, in the semiconductor device manufactured based on Examples 1 to 11 and Comparative Example 3, one cycle was -4.
1000 cycles of a temperature cycle test at 0 ° C./30 minutes to 125 ° C./30 minutes were performed. Table 3 shows the results.
From Table 3, no change in the connection resistance was observed in the semiconductor devices manufactured based on Examples 1 to 11. On the other hand, the semiconductor device manufactured based on Comparative Example 3 has 10
An open failure was found in the continuity measurement evaluation after 00 cycles.

[0105]

According to the first method of the present invention, a method for connecting a circuit substrate includes forming a first resin composition layer on a wiring surface of the first circuit substrate, and forming the first resin composition layer on the first resin composition layer. Alternatively, a second resin composition layer having a lower melt viscosity than the first resin composition layer is formed on the wiring surface of the second circuit substrate, and the wiring surfaces of the first and second circuit substrates are interposed with bump electrodes. And the first and second circuit boards are joined with the resin composition, and the wiring between the circuit boards is electrically connected with the bump electrodes, so that the wiring remains on the resin composition layer. The voids are reduced, and the thermal stress between the resin composition layer and the circuit substrate is also reduced, so that a highly reliable circuit substrate connection method can be obtained.

According to the method for connecting a circuit substrate according to the second method of the present invention, since the circuit substrate is a semiconductor chip or a wiring substrate in the first method, voids remaining in the resin composition layer can be reduced. The thermal stress between the resin composition layer and the circuit substrate is also reduced, so that a highly reliable semiconductor device or multilayer wiring board can be obtained.

The method for connecting a circuit board according to the third method of the present invention is the method for connecting a circuit board according to the first or second method, after forming the first resin composition layer on the wiring surface of the first circuit board. , The second resin composition layer is formed.
Although it is difficult to obtain a layered structure, those having good material properties can be used alone.

In the method for connecting circuit boards according to the fourth method of the present invention, since the surface shape of the second resin composition layer is formed to be hemispherical in the above-described third method, the circuit board can be connected with the circuit board at a time of joining. In addition, the second resin composition can be flowed to the periphery to effectively suppress the generation of voids.

In the method of connecting a circuit substrate according to the fifth method of the present invention, a resin composition that is liquid at room temperature is used as the second resin composition layer in the third or fourth method. The application of the resin composition becomes easy. In particular, it is advantageous for forming the surface shape of the resin composition layer into a hemispherical shape by a dispensing method or the like.

The method of connecting a circuit substrate according to the sixth method of the present invention is the same as the first or second method, except that the second resin composition layer is laminated on the first resin composition layer. Since the film is attached to the wiring surface of the first circuit substrate,
Since the resin composition is a film, it is easy to handle and the production efficiency can be improved.

The method for connecting a circuit substrate according to a seventh method of the present invention is the method according to any one of the first to sixth methods, wherein the amount of resin in the second resin composition layer is less than the first resin composition. Since the amount of resin in the second resin composition layer is smaller than the amount of resin in the first resin composition layer, the first resin composition layer can secure the required amount of resin between circuit substrates even if most of the second resin composition layer flows out. The composition can be prevented from becoming excessive.

The method of connecting a circuit substrate according to an eighth method of the present invention is the method according to any one of the first to seventh methods, wherein the first and second resin composition layers are formed by melting the bump electrode at a melting point. Since the resin composition layer is melted at a low temperature, the resin composition layer can be aligned with high accuracy without melting the bump electrode, and the reliability of electrical connection is improved.

The method of connecting a circuit substrate according to the ninth method of the present invention is the same as the method of any one of the first to eighth methods, since the first or second resin composition layer contains an epoxy resin. It is possible to impart adhesiveness to the resin composition.

According to a tenth method of the present invention, there is provided a method of connecting a circuit substrate according to any one of the first to eighth methods, wherein the first or second resin composition layer is made of an epoxy resin and a phenol cured resin. Since the resin composition contains the agent, the epoxy resin can impart adhesiveness to the resin composition, and the phenol curing agent can cure the epoxy resin without concern for hydrolysis.

The method for connecting a circuit substrate according to the eleventh method of the present invention is the same as the method of any one of the first to tenth methods, since the first or second resin composition layer contains a filler. In addition, the thermal expansion coefficient of the resin composition layer can be reduced, the thermal stress generated between the circuit substrate and the resin composition can be reduced, and low water absorption can be imparted.

According to a twelfth method of the present invention, in any one of the first to eleventh methods, bump electrodes are formed on both the first and second circuit substrates. Therefore, warpage and undulation of the circuit substrate, variations in the height of the bump electrodes, and the like can be buffered, and the electrical connection can be performed more reliably.

Since the composite circuit board according to the first aspect of the present invention is manufactured by using the circuit board connecting method according to any one of the first to twelfth aspects, the voids remaining in the resin composition layer are reduced. In addition, the thermal stress between the resin composition layer and the circuit substrate is reduced, and a highly reliable composite circuit substrate can be obtained.

The composite circuit substrate according to the second configuration of the present invention is a composite circuit substrate in which opposing circuit substrates are joined with a resin composition and wiring between the circuit substrates is electrically connected by bump electrodes. A circuit substrate, wherein the resin composition is a plurality of types of resin compositions having different melt viscosities, so that voids remaining in the resin composition layer are reduced, and thermal stress between the resin composition layer and the circuit substrate is reduced. And a highly reliable composite circuit substrate can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a method of connecting circuit substrates according to a first embodiment of the present invention in the order of steps.

FIG. 2 is an explanatory view showing a method of connecting circuit substrates according to a second embodiment of the present invention in the order of steps.

FIG. 3 is an explanatory view showing a method of connecting circuit substrates according to a third embodiment of the present invention in the order of steps.

FIG. 4 is an explanatory view showing a method of connecting a circuit substrate according to a fourth embodiment of the present invention in the order of steps.

FIG. 5 is an explanatory view showing a method of connecting circuit substrates according to a fifth embodiment of the present invention in the order of steps.

FIG. 6 is an explanatory view showing a method of connecting circuit substrates according to a comparative example in the order of steps.

FIG. 7 is an explanatory view showing a method of connecting circuit substrates according to another comparative example in the order of steps.

[Explanation of symbols]

1 second circuit substrate (wiring board), 2 bump electrode, 3
Resin composition layer, 31 first resin composition, 32 second resin composition layer, 4 heating stage, 5 second circuit substrate (semiconductor chip), 6 bump electrode, 7 heating head,
8 External bump electrodes, 10 dispensers.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hirofumi Fujioka 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation (72) Inventor Toshihiro Tomita 2-3-2 Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Naoto Ueda 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 5E319 AA03 AB05 BB04 BB20 CC33 CC58 CD16 GG05 5E346 AA22 CC09 CC41 EE12 FF24 GG25 GG28 HH11 5F044 KK01 KK16 LL11 QQ01 RR17

Claims (14)

[Claims] A first resin composition layer is formed on a wiring surface of a first circuit substrate, and a first resin composition layer is formed on the first resin composition layer or on a wiring surface of a second circuit substrate. Forming a second resin composition layer having a lower melt viscosity than the material layer, arranging the wiring surfaces of the first and second circuit substrates facing each other with a bump electrode interposed therebetween, and connecting the first and second circuit substrates. A method of connecting a circuit substrate, comprising: bonding with the resin composition; and electrically connecting the wiring between the circuit substrates with the bump electrode. 2. The method according to claim 1, wherein the circuit substrate is a semiconductor chip or a wiring substrate. 3. The circuit according to claim 1, wherein the second resin composition layer is formed after the first resin composition layer is formed on the wiring surface of the first circuit substrate. How to connect the substrate. 4. The method according to claim 3, wherein the surface of the second resin composition layer is formed in a hemispherical shape. 5. The method according to claim 3, wherein a resin composition that is liquid at room temperature is used as the second resin composition layer. 6. A film having a structure in which a second resin composition layer is laminated on a first resin composition layer is attached to a wiring surface of a first circuit substrate. The method for connecting circuit substrates according to the above. 7. The method for connecting circuit boards according to claim 1, wherein the amount of resin in the second resin composition layer is smaller than the amount of resin in the first resin composition layer. 8. The method according to claim 1, wherein the first and second resin composition layers are melted at a temperature lower than a melting point of the bump electrode. 9. The method according to claim 1, wherein the first or second resin composition layer contains an epoxy resin. 10. The method according to claim 1, wherein the first or second resin composition layer contains an epoxy resin and a phenol curing agent. 11. The method according to claim 1, wherein the first or second resin composition layer contains a filler. 12. The method according to claim 1, wherein the bump electrodes are formed on both the first and second circuit substrates. 13. A composite circuit substrate manufactured by using the circuit substrate connection method according to claim 1. 14. A composite circuit substrate in which opposing circuit substrates are joined by a resin composition and wiring between the circuit substrates is electrically connected by bump electrodes, wherein the resin composition is melted. A composite circuit substrate comprising a plurality of types of resin compositions having different viscosities.