JPH1154667A - Hybrid integrated circuit device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a board against cracking by mounting a second board on a first board constituting a major part and resin sealing the first and second boards compactly such that no air gap is present between. SOLUTION: After a second board 2 and a device 7 are mounted on a first board 1, a compact resin 31 is injected into the gap between the first and second boards 1, 2 and a lead terminal 9 is fixed by solder 8 to the first board 1 thus producing a half-finished produced 33 to be packaged. The half-finished produced 33 is then fitted in a case 10 under a state where the lead terminal 9 is directed upward and the first board 1 is held horizontally, and the second board 2 is immersed into a moisture resistant liquid resin 34 along with the device 7 mounted on the same mount surface as the second board 2. The mount surface on the opposite side of the second board 2 is filled with a specified quantity of moisture resistant liquid resin 34 and heat treated for a predetermined. Consequently, the moisture resistant liquid resin 34 is cured and moisture resistant resin 32 sealing is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid integrated circuit device, and more particularly to a hybrid integrated circuit device having high reliability with respect to a change in environmental temperature.

[0002]

2. Description of the Related Art FIG. 4 is a cross-sectional view showing a conventional hybrid integrated circuit device. In FIG. 4, reference numeral 1 denotes a first substrate constituting a main part of the hybrid integrated circuit device, and reference numeral 2 denotes a device mounted on the first substrate 1. A second substrate, 4 is a conductor material constituting wiring, 5 is a component mounting land for mounting various components, 6 is a protective cover, 7 is various mounting components mounted on the first substrate 1, and 8 is a mounting component. solder,
Reference numeral 9 denotes a lead terminal, 10 denotes a case for accommodating the substrates 1, 2 and the mounted components 7, and 11 denotes a urethane resin which is a kind of thermosetting resin filled in the case 10.

In this hybrid integrated circuit device, the second substrate 2
The mounting components 7 are mounted on the first substrate 1 by solder 8, and the lead terminals 9 are also attached to the first substrate 1 by solder 8. The exterior is made by filling a case 10 with a urethane resin 11. The urethane resin 11 has a function of maintaining moisture resistance and bonding and fixing the first substrate 1 on which the mounting components 7 are mounted and the case 10.

Next, a case sealing step of the hybrid integrated circuit device will be described with reference to FIG. First, FIG.
As shown in (2), the second substrate 2 and the mounted component 7 are mounted on the first substrate 1 by solder 8 and the lead terminals 9 are also attached to the first substrate 1 by solder 8 to obtain a semi-finished product 21 before exterior. . Next, as shown in FIG. 2B, the case 10 is placed horizontally, and a predetermined amount of the liquid urethane resin 2 is placed in the case 10.
Inject 2.

Next, as shown in FIG. 1C, the semi-finished product 21 is fitted into a horizontally placed case 10 with the lead terminals 9 facing upward and the first substrate 1 held horizontally. The second substrate 2 and the mounting component 7 on the same mounting surface as the mounting surface of the second substrate 2 are immersed in the liquid urethane resin 22.
In this case, since the first substrate 1 is immersed in the liquid urethane resin 22 in a horizontal state, the liquid urethane resin 22 does not sufficiently penetrate between the first substrate 1 and the second substrate 2 and the air 1
2 may not be completely removed and may remain.

Next, as shown in FIG. 1D, a predetermined amount of liquid urethane resin 22 is filled on the mounting surface of the first substrate 1 opposite to the second substrate 2. Thereafter, a heat treatment is performed at a predetermined temperature for a predetermined time, so that the liquid urethane resin 2
2 is cured to form a urethane resin 11, and the first substrate 1,
The entire mounting component including the second substrate 2 and the mounting component 7 is packaged. Here, the air 12 remaining between the first substrate 1 and the second substrate 2 remains in the urethane resin 11 as a void (gap) 13 as it is.

[0007]

A first problem is that when a ceramic substrate is used as the first substrate 1 or the second substrate 2, for example, a temperature cycle test or the like is performed. When the expansion and contraction of the urethane resin is repeated due to the temperature change by repeating the high and low temperatures, the ceramic substrate receives the stress caused by this expansion and contraction,
The point is that cracks and cracks are generated in the ceramic substrate due to thermal stress that is repeated between high and low temperatures.

In this case, if both the front and back surfaces of the ceramic substrate are filled with the urethane resin, the force exerted on the ceramic substrate due to the expansion and contraction of the urethane resin is offset on both surfaces of the substrate, but one side of the substrate does not. If the surface is hollow due to voids, bending stress is applied to the substrate, and cracks and cracks occur in the substrate.

The problem is that, in the case sealing step of the hybrid integrated circuit device described above, when the semi-finished product 21 is fitted into the case 10 and immersed in the liquid urethane resin 22, the first substrate 1 and the second substrate When the liquid 12 is hardened, the air 12 cannot be completely removed.
No. 3 is a problem caused by remaining in the urethane resin 11.

The second problem is that even if the substrate is not cracked or cracked by the effect of the voids 13 remaining in the urethane resin 11, the mounted components 7 to be mounted and the solder 8 of the second substrate 2 Also, since mechanical stress is applied, the solder 8 may be peeled or distorted, and the reliability of the connection portion is concerned. For example, mounted components 7
When a void exists around it, the urethane resin 11 expands, so that a stress toward the void acts on the mounted component 7, and this stress is directly applied to the solder 8 and becomes a stress. It is.

The present invention has been made in view of the above circumstances, and does not cause cracks or cracks in a substrate even when a thermal stress that repeats high and low temperatures is applied, and may cause poor connection due to solder. Accordingly, it is an object of the present invention to provide a hybrid integrated circuit device capable of improving reliability.

[0012]

In order to solve the above-mentioned problems, the present invention employs the following hybrid integrated circuit device. That is, in the hybrid integrated circuit device according to the first aspect, at least one or more second substrates are mounted on the first substrate constituting the main part, and the first substrate and the second substrate are resistant to moisture. In a hybrid integrated circuit device sealed in a case with a resin, at least the space between these substrates is sealed with a dense resin having no void.

According to a second aspect of the present invention, in the hybrid integrated circuit device, the moisture-resistant resin is a urethane-based resin.

According to a third aspect of the present invention, in the hybrid integrated circuit device, the dense resin is a resin having an expansion coefficient close to those of the first substrate and the second substrate.

According to a fourth aspect of the present invention, in the hybrid integrated circuit device, the entire mounting component including the first substrate and the second substrate is covered with a resin having an expansion coefficient close to those of the first substrate and the second substrate. It is a thing.

According to a fifth aspect of the present invention, there is provided the hybrid integrated circuit device, wherein the components mounted on the first substrate and / or the second substrate and between the mounted components and the substrate mounted with the components are mounted. A resin having an expansion coefficient close to that of the first substrate and the second substrate is injected between them.

According to a sixth aspect of the present invention, there is provided the hybrid integrated circuit device, wherein the first substrate and / or the second substrate are close to the first substrate and the second substrate in a region where a plurality of mounting components are mounted. A resin having an expansion coefficient is injected and the plurality of mounted components are pre-coated.

According to a seventh aspect of the present invention, the resin having an expansion coefficient close to those of the first substrate and the second substrate is a phenolic resin.

In the hybrid integrated circuit device according to the first, second, third or seventh aspect of the present invention, at least the space between these substrates is sealed with a dense resin having no space, so that a space is formed between these substrates. There is no danger of occurrence. This allows
Even if the moisture-resistant resin expands and contracts due to temperature changes due to repeated high and low temperatures, such as in a temperature cycle test, there is no void around these substrates, eliminating the risk of bending stress acting on the substrates. In addition, it is possible to prevent the occurrence of defects such as cracks and cracks in the substrate.

Further, since the substrates are sealed with a dense resin, the substrates are fixed to each other, and even when a mechanical stress is applied to these substrates due to a stress caused by expansion and contraction of the moisture resistant resin. The mechanical stress on the solder portion of the substrate is reduced, and there is no possibility that the solder portion will be peeled or distorted, and the reliability of the connection portion will be improved.

In the hybrid integrated circuit device according to a fourth aspect, the entire mounting component including the first substrate and the second substrate is covered with a resin having an expansion coefficient close to those of the first substrate and the second substrate. As a result, the entire mounting components including these substrates are fixed, and even if the stress due to the expansion and contraction of the moisture-resistant resin applies mechanical stress to the entire mounting components including these substrates, the mounting of these substrates and each component is also possible. The mechanical stress on the solder portion is reduced, and the reliability of the solder portion of these boards and components is improved.

In the hybrid integrated circuit device according to the fifth aspect, between the mounted components mounted on the first substrate and / or the second substrate, and between the mounted components and the substrate mounted with the mounted components. In the meantime, by injecting a resin having an expansion coefficient close to that of the first substrate and the second substrate, by injecting the resin between the components and the component and the substrate, which are portions where voids are easily formed, A gap is prevented from being formed between the components to be mounted and between the component and the substrate. As a result, even when the stress due to expansion and contraction of the moisture-resistant resin applies mechanical stress to these components and the substrate, the mechanical stress on the solder portions of these components is reduced, and the solder portions of these components are reduced. Reliability is improved.

According to a sixth aspect of the present invention, in the hybrid integrated circuit device, the first substrate and / or the second substrate are close to the first substrate and the second substrate in a region where a plurality of mounting components are mounted. By injecting a resin having an expansion coefficient and pre-coating the plurality of mounted components, the entire components mounted in this region are fixed, and stress due to expansion and contraction of the moisture-resistant resin causes mechanical stress on each component in this region. Is added, the mechanical stress on the solder portion of each component in this region is reduced, and the reliability of the solder portion of each component in this region is improved.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the hybrid integrated circuit device of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a sectional view showing a hybrid integrated circuit device according to a first embodiment of the present invention. In the figure, reference numeral 31 denotes a first substrate 1, a second substrate 2 and 32 is a dense resin having no voids (voids) for sealing the space between them, and 32 is a moisture-resistant resin for sealing the entire mounting components such as the first substrate 1, the second substrate 2 and the mounting components 7 in the case 10. is there. The dense resin 31 is a resin whose expansion coefficient is substantially equal to that of the first substrate 1 and the second substrate 2, and a phenol resin is preferably used. As the moisture-resistant resin 32, a urethane resin (urethane-based resin) is preferably used.

The outline of this hybrid integrated circuit device will be described. Wiring patterns made of a conductive material 4 are formed on both surfaces of a first substrate 1 and component mounting lands 5 of the conductive material 4 are formed.
Others are covered by a protective cover 6. The second substrate 2 and the mounted component 7 are mounted on the component mounting land 5, and are fixed with solder 8 and electrically connected. The lead terminals 9 are also fixed by solder 8 and are electrically connected. These first substrate 1 and second substrate 2
The mounted component 7 is sealed in the case 10 by the moisture-resistant resin 32.

In this hybrid integrated circuit device, the first substrate 1
Between the first substrate 2 and the second substrate 2 is a dense resin 31 having no voids.
Even when subjected to a stress that repeatedly applies a high temperature and a low temperature as in a temperature cycle test, for example, the bending resistance of the substrates 1 and 2 is reduced even when the moisture resistant resin 32 repeatedly expands and contracts. However, it is possible to prevent problems such as substrate cracks and cracks from occurring.

The dense resin 31 has a role of mechanically fixing the first substrate 1 and the second substrate 2, and its expansion coefficient is different from that of the materials of the substrates 1 and 2. Since they are almost equal, it is possible to prevent mechanical stress on the solder 8 even when repeated stress of temperature is applied. Therefore, it is possible to improve the reliability of the connection part by the solder 8.

Next, a case sealing step of the hybrid integrated circuit device will be described with reference to FIG. First, FIG.
As shown in (2), after mounting the second substrate 2 and the mounting component 7 on the first substrate 1 by soldering 8, a dense resin 31 is injected between the first substrate 1 and the second substrate 2. , Lead terminal 9
Is attached to the first substrate 1 with the solder 8 to obtain a semi-finished product 33 before the exterior. As the dense resin 31, a phenol resin is preferable. Next, as shown in FIG. 2B, the exterior case 10 is placed horizontally, and
A predetermined amount of a thermosetting liquid moisture-resistant resin 34 is injected into the inside. As the liquid moisture-resistant resin 34, a liquid urethane resin is preferable.

Next, as shown in FIG. 1C, the semi-finished product 33 is placed in the case 10 placed horizontally with the lead terminals 9 facing up and the first substrate 1 held horizontally. The second substrate 2 and the mounting component 7 on the same mounting surface as the mounting surface of the second substrate 2 are immersed in the liquid moisture-resistant resin 34. In this case, the space between the first substrate 1 and the second substrate 2 is already filled with the dense resin 31, so that no air pool is generated.

Next, as shown in FIG. 1D, a predetermined amount of liquid moisture-resistant resin 34 is filled on the mounting surface of the first substrate 1 opposite to the second substrate 2. Thereafter, a heat treatment is performed at a predetermined temperature for a predetermined time so that the liquid moisture-resistant resin 3
4 is cured to form a moisture-resistant resin 32, and the entire mounted component including the first substrate 1, the second substrate 2, and the mounted component 7 is packaged.

In the case sealing step, the space between the first substrate 1 and the second substrate 2 was filled with the dense resin 31.
The packaging can be performed without a void between the substrates 1 and 2. Further, even if the stress from the moisture resistant resin 32 is applied to the substrates 1 and 2, the voids do not exist between the substrates 1 and 2 due to the filled dense resin 31, so that the bending stress is hardly applied. No cracks or cracks occur in the substrates 1 and 2.

According to the hybrid integrated circuit device of the present embodiment,
Since the dense resin 31 having no void is filled between the first substrate 1 and the second substrate 2, the moisture-resistant resin 32 around these substrates 1 and 2 expands and contracts due to a change in environmental temperature. Even if it occurs, no bending stress acts on the substrates 1 and 2, cracks and cracks of the substrates 1 and 2 can be prevented, and reliability with respect to heat resistance can be improved.

Further, the first substrate 1 and the second substrate 2 are
Since it is mechanically fixed with a dense resin 31 having an expansion coefficient substantially equal to those of the substrates 1 and 2, even if the surrounding moisture resistant resin 32 expands and contracts due to a change in environmental temperature, the solder 8 No mechanical stress is applied to the part,
The expansion / contraction of the resin 31 itself does not affect the solder 8 portion, so that peeling, distortion, cracks and the like can be prevented from being generated in the mounted solder 8 portion. Reliability can be improved.

(Second Embodiment) FIG. 3 is a sectional view showing a hybrid integrated circuit device according to a second embodiment of the present invention. The difference from the hybrid integrated circuit device is that the first substrate 1 and the second substrate
A void-free dense resin 31 having an expansion coefficient substantially equal to (close to) the substrate 2 of the first substrate 1 and the second substrate 2
And that it is applied so as to cover the whole including the mounted components 7.

In this hybrid integrated circuit device, the dense resin 3
Since the entire mounting component is fixed by 1, the moisture-resistant resin 3
Even when the stress due to expansion and contraction of 2 applies mechanical stress to the entire mounted component, the mechanical stress on the solder 8 of the substrates 1 and 2 and each mounted component 7 can be reduced, It is possible to improve the reliability of the solders 8 of the substrates 1 and 2 and each mounting component 7.

In the hybrid integrated circuit device of this embodiment, the dense resin 31 having an expansion coefficient substantially equal to that of the first substrate 1 and the second substrate 2 is applied to the first substrate 1 and the second substrate 2. Although the coating is performed so as to cover the entirety including the mounting components 7, various configurations can be made according to the shapes and sizes without being limited to the present embodiment.

For example, a configuration in which the resin 31 is injected between mounted components mounted on the first substrate and / or the second substrate, and between the mounted components and the substrate on which the mounted components are mounted, Alternatively, the resin 31 may be injected into a region of the first substrate and / or the second substrate where a plurality of mounted components are mounted, and the plurality of mounted components may be pre-coated.

[0039]

As described above, according to the first aspect of the present invention,
According to the hybrid integrated circuit device described in 2, 3 or 7, since at least the space between these substrates is sealed with a dense resin having no space, there is no possibility that a space is formed between these substrates. Even if the moisture-resistant resin expands or contracts, there is no gap around these substrates, and there is no risk of bending stress acting on the substrates, so that problems such as cracks and cracks are prevented from occurring on the substrates. Can be.

Further, since the substrates are sealed with a dense resin, these substrates are fixed to each other, and the expansion of the moisture-resistant resin is prevented.
Even when a stress due to shrinkage applies a mechanical stress to these substrates, it is possible to reduce the mechanical stress on the solder portions of these substrates. Therefore, there is no possibility that peeling, distortion, cracks, etc. will occur in the solder portion, and the reliability of the connection portion by solder can be improved.

According to the hybrid integrated circuit device of the fourth aspect, the entire mounting component including the first substrate and the second substrate is made of a resin having an expansion coefficient close to that of the first substrate and the second substrate. Even when the stress due to the expansion and contraction of the moisture-resistant resin applies mechanical stress to the entire mounted components, the mechanical stress on the solder parts of these boards and components can be alleviated. It is possible to improve the reliability of the solder part of the board and each component.

According to the hybrid integrated circuit device of the fifth aspect, between the mounted components mounted on the first substrate and / or the second substrate and between the mounted components and the substrate mounted with the mounted components Between the first substrate and the second substrate, a resin having an expansion coefficient close to that of the first substrate and the second substrate is injected. In addition, mechanical stress on the solder portion of these components can be reduced, and the reliability of the solder portions of these components can be improved.

According to the hybrid integrated circuit device of the sixth aspect, the first substrate and / or the second substrate are provided in a region of the first substrate and / or the second substrate where a plurality of mounting components are mounted.
Since a resin having an expansion coefficient close to that of the substrate is injected and the plurality of mounted components are pre-coated, the stress due to the expansion and contraction of the moisture-resistant resin may cause a mechanical stress on each component in this region. The mechanical stress on the solder portion of each component can be reduced, and the reliability of the solder portion of each component in this region can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a hybrid integrated circuit device according to a first embodiment of the present invention.

FIG. 2 is a process diagram showing a case sealing step of the hybrid integrated circuit device according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a hybrid integrated circuit device according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a conventional hybrid integrated circuit device.

FIG. 5 is a process diagram showing a case sealing step of a conventional hybrid integrated circuit device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first substrate 2 second substrate 4 conductive material 5 component mounting land 6 protective cover 7 mounting component 8 solder 9 lead terminal 10 case 11 urethane resin 12 air 13 void (gap) 21 semi-finished product 22 liquid urethane resin 31 dense Resin 32 Moisture resistant resin 33 Semi-finished product 34 Liquid moisture resistant resin

Claims (7)

[Claims] At least one or more second substrates are mounted on a first substrate constituting a main part, and the first and second substrates are sealed in a case with a moisture-resistant resin. A hybrid integrated circuit device, characterized in that at least the space between the substrates is sealed with a dense resin having no void. 2. The hybrid integrated circuit device according to claim 1, wherein said moisture-resistant resin is a urethane-based resin. 3. The hybrid integrated circuit device according to claim 1, wherein said dense resin is a resin having an expansion coefficient close to that of said first substrate and said second substrate. 4. The whole mounting component including the first substrate and the second substrate is covered with a resin having an expansion coefficient close to that of the first substrate and the second substrate. A hybrid integrated circuit device as described. 5. The method according to claim 1, wherein the first substrate and / or the second substrate are mounted on the first substrate and / or the second substrate, and between the mounted component and the substrate on which the mounted component is mounted. 2. The hybrid integrated circuit device according to claim 1, wherein a resin having an expansion coefficient close to that of the second substrate is injected. 6. A resin having an expansion coefficient close to that of the first substrate and the second substrate is injected into a region of the first substrate and / or the second substrate on which a plurality of mounting components are mounted. 2. The hybrid integrated circuit device according to claim 1, wherein a plurality of mounted components are pre-coated. 7. The hybrid integrated circuit device according to claim 3, wherein the resin having an expansion coefficient close to those of the first substrate and the second substrate is a phenolic resin. .