JPH1131761A - Semiconductor component and manufacture of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the outflow of liquid resin to the outside of a sealing range, in a simple constitution at the time of application and hardening liquid resin on a substrate, and providing a sealing resin layer. SOLUTION: After a semiconductor chip has been mounted on a substrate A, and electrically connected with this, a liquid resin B is applied so that the semiconductor chip can be covered. In the application process, the liquid resin B is gradually leaded and spread from the central side of the substrate A to the outer side. A contact angle θ at a contact point P1 at the edge part of the liquid resin B is balanced and stabilized, when Rs=Rl cosθ+Rsl (where Rs, Rl and Rsl are respectively the surface tension of the substrate A, the surface tension of the liquid resin B, and the surface tension of a boundary face) is established. When the edge part of the substrate A is microscopically is rounded, an apparent contact angle θ' of the liquid resin B made with the upper face of the substrate A is made large in the balanced state at a contact point P2 at the edge part of the substrate A such that the edge part of the substrate A can function as the flow stopper for the liquid resin B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor component in which a semiconductor chip mounted on a substrate is sealed with a sealing resin layer, and a method for manufacturing the same.

[0002]

For example, BGA, MCM
7 and 8, after a semiconductor chip (not shown) is mounted on a substrate 1 such as a ceramic substrate and an electrical connection (such as wire bonding) with the substrate 1 is performed, The semiconductor chip and the like on the substrate 1 are resin-sealed by the sealing resin layers 2 and 3. 7 and 8 show an example of a BGA (ball grid array) package. On the back side of the substrate 1, a number of ball-shaped solder bumps 4 are arranged and provided. I have.

At this time, as a method of forming the sealing resin layers 2 and 3, a method using a mold compound using a mold as shown in FIG. 7 and a liquid method so as to cover a semiconductor chip as shown in FIG. And hardening the resin. However, in the case of using a mold, the cost of manufacturing the mold is high in the case of small-scale production.
In the case where a small number of products are mainly manufactured, such as M (multi-chip module), a method of applying a liquid resin as shown in FIG. 8 is generally adopted.

When the sealing resin layer 3 is formed by applying a liquid resin on the substrate 1 as described above,
It is necessary to prevent the liquid resin from flowing out of the area where the upper sealing resin layer is to be formed. Therefore, conventionally, in order to prevent the flow of the liquid resin, Japanese Patent Application Laid-Open No. 58-484
No. 42 and JP-A-61-216438, a resin frame (printing frame) is formed around the mounting position of the semiconductor chip to serve as a wall for preventing liquid resin from flowing out. Filling the frame with a casting resin material has been considered.

However, in such a method, in order to obtain a sufficient effect, the resin frame must be formed to have a sufficient height and a thick wall shape, and it takes considerable time and effort to form the resin frame. And the disadvantage that many materials are required. Also,
There was also a concern that the size of the package would be increased by the wall thickness (width) of the resin frame.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a sealing resin layer by applying a liquid resin on a substrate and curing the liquid resin. Accordingly, it is an object of the present invention to provide a semiconductor component capable of preventing a liquid resin from flowing out of a sealing range and a method of manufacturing the same.

[0007]

SUMMARY OF THE INVENTION The present inventor has found that when a liquid resin is applied to the upper surface of a substrate and the liquid resin is spread, when the end of the liquid resin reaches the edge of the substrate, It has the property that its surface tension has increased, and it does not easily overflow outside the edge of the substrate. He has achieved the invention. The details of the principle are considered as follows.

That is, as shown in FIG. 1A, when a certain amount of liquid resin B is applied to the upper surface of a substrate A, when the contact point P1 at the end is located on the substrate A, The rise angle (contact angle) θ of the liquid resin B at the point P1 is as follows: Rs = Rl cos θ + Rsl (1) (where Rs is the magnitude of the surface tension of the substrate A, and Rl is the magnitude of the surface tension of the liquid resin B) , Rsl is the substrate A and the liquid resin B
(The magnitude of the surface tension at the interface with the surface) is established and stable. When the liquid resin B is further applied from the state shown in FIG. 1A, the liquid resin B spreads again until the same angle θ is obtained.

However, when the edge of the substrate A is viewed microscopically, as shown in FIG. 1 (b), it is considered that the substrate has a so-called R, so that the liquid resin B is additionally applied and When the contact point P2 reaches the edge of the substrate A, the tangential direction of the contact point P2 changes from a horizontal state to an inclined shape that descends outward, and the direction of the surface tension (Rs, R1, Rsl) changes. In this state, the balance is stabilized where the above equation (1) is satisfied. Since the R portion at the edge of the substrate A is very small, the influence of gravity is extremely small as compared with the surface tension and is considered to be almost negligible.

In this case, in a balanced state at the edge of the substrate A, the swelling angle θ ′ of the liquid resin B at the contact point P2 with respect to the upper surface of the substrate A (ie, the apparent contact angle) θ ′ is shown in FIG. It becomes larger than the angle θ shown in a). This means that when the edge of the liquid resin B reaches the edge of the substrate A, the edge of the substrate A
Means that the apparent contact angle with respect to the upper surface of the substrate A exceeds the angle θ even if the apparent contact angle with the upper surface of the substrate A exceeds the angle θ ′. It does not overflow.

According to a first aspect of the present invention, a semiconductor resin is mounted on a substrate, and a sealing resin layer for sealing the semiconductor chip by coating and curing a liquid resin on the substrate. The sealing resin layer is provided in a state where at least a part of the edge of the substrate is kept from flowing the liquid resin.

According to this, since the sealing resin layer is provided in a state where at least a part of the edge of the substrate is kept from flowing the liquid resin, the liquid resin is applied when the liquid resin is applied as described above. The resin can be effectively prevented from overflowing from the edge of the substrate, and the liquid resin can be prevented from flowing out of the sealing range. Also, it is only necessary to set the edge of the substrate to coincide with the edge of the resin sealing, and there is no need to separately provide a frame or the like as a wall for preventing the liquid resin from flowing out. Can be done.

[0013] In this case, the edge of the substrate, which serves as a stopper for the liquid resin, may be formed in an acute angle with a reverse taper toward the back surface side. According to this, the amount of change in the direction of the surface tension at the contact point of the liquid resin at the edge of the substrate can be further increased, and the effect of preventing the liquid resin from overflowing can be further enhanced.

Further, a flow stopper having a surface tension smaller than that of the substrate may be provided at an edge portion of the substrate at which the liquid resin stops flowing (the invention of claim 3). According to this, Rs in the above equation (1) is reduced, and as a result, cos θ can be reduced, that is, the angle θ at the time of balancing can be increased, and the effect of preventing overflow of the liquid resin can be further enhanced. Can be.

By the way, in the case of MCM, COB, etc., it may be difficult or impossible to bring the end of the sealing resin layer to the edge of the substrate due to the design of the semiconductor component. A semiconductor component according to a fourth aspect of the present invention is configured such that a semiconductor chip is mounted on a substrate and a sealing resin layer for sealing the semiconductor chip is provided by applying and curing a liquid resin on the substrate. The sealing resin layer forming region on the substrate has a stepped shape higher than the surrounding portion.

According to this, the edge of the step portion higher than the peripheral portion on the substrate can be given the same function as the edge of the substrate as described above, and as a result, the sealing resin layer Even when it is difficult to bring the edge to the edge of the substrate, the liquid resin can be effectively prevented from overflowing from the edge of the step when the liquid resin is applied, and the The outflow outside the sealing range can be prevented. In addition, a simple configuration in which steps are provided in a so-called island shape on the substrate can be achieved.

According to a fifth aspect of the present invention, there is provided a method of manufacturing a semiconductor component, comprising mounting a semiconductor chip on a substrate and providing a sealing resin layer for sealing the semiconductor chip. In the method, a step of mounting a semiconductor chip on the substrate, a step of applying a liquid resin to cover the semiconductor chip on the substrate, and a step of curing the liquid resin, the liquid resin The application step is characterized in that at least a part of the edge of the substrate is performed with the liquid resin stopped.

According to this, the step of applying the liquid resin so as to cover the semiconductor chip mounted on the substrate is performed in a state where at least a part of the edge of the substrate is kept from flowing the liquid resin. So, as mentioned above, with a simple configuration,
When the liquid resin is applied, the liquid resin can be effectively prevented from overflowing from the edge of the substrate, and the liquid resin can be prevented from flowing out of the sealing range.

According to a sixth aspect of the present invention, there is provided a method for manufacturing a semiconductor component, comprising: mounting a semiconductor chip on a substrate;
A method of manufacturing a semiconductor component provided with a sealing resin layer for sealing the semiconductor chip, wherein a step of forming an island-shaped step portion higher than a peripheral portion in a sealing resin layer forming region on the substrate is provided. And a step of mounting a semiconductor chip on the island-shaped step, a step of applying a liquid resin to cover the semiconductor chip on the island-shaped step, and a step of curing the liquid resin, The application step of the liquid resin is characterized in that the step is performed in a state where the edge of the island-shaped step portion is kept from flowing the liquid resin.

According to this, as described above, the liquid resin can be effectively prevented from overflowing from the edge portion of the island-shaped step portion at the time of applying the liquid resin with the relatively simple structure,
It is possible to prevent the liquid resin from flowing out of the sealing range. In this case, the island-shaped step portion can be formed by applying a solder resist to the sealing resin layer formation region on the substrate (the invention of claim 7), thereby forming the island-shaped step portion. Can be easily performed. still,
According to the experiment of the present inventor, the height of the island-shaped step portion is 30 to 5
If it is 0 μm or more, the desired effect can be obtained.

Further, in each of the above-mentioned manufacturing methods, it is desirable that the step of applying the liquid resin is performed by multipoint application or scanning application (the invention of claim 8). Thereby, the application step of the liquid resin can be performed more efficiently than in the case of one-point application.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to FIGS. 2 to 6 and FIG. (1) First Embodiment FIG. 2 shows a configuration of a semiconductor component (BGA) 11 according to a first embodiment (corresponding to claims 1, 5 and 8) of the present invention.

The semiconductor component 11 is constructed by mounting a semiconductor chip 13 on the surface of a rectangular substrate 12 made of a ceramic substrate or a printed circuit board. Although not shown in detail, a front surface electrode is formed on the front surface of the substrate 12, and a large number of back electrodes connected to the front electrode through through holes and the like are formed on the back surface of the substrate 12. It is formed in a lattice shape, and on the back surface of the substrate 12,
A large number of ball-shaped solder bumps 14 connected to the respective back electrodes are provided.

On the front side of the substrate 12, the semiconductor chip 13 is connected to a surface electrode by a bonding wire or the like (not shown).
The semiconductor chip 13 is resin-sealed by a sealing resin layer 15 made of, for example, an epoxy (or silicon) thermosetting resin. At this time, the sealing resin layer 15 is designed so that the formation region thereof coincides with the entire substrate 12, and the sealing resin layer 15 covers the entire upper surface of the substrate 12, that is, the end of the sealing resin layer 15. The edge is provided so as to coincide with the edge of the substrate 12.

Now, a procedure for manufacturing the semiconductor component 11 configured as described above will be described. First, a step of mounting the semiconductor chip 13 on the substrate 12 on which the front surface electrode and the back surface electrode are formed as described above and performing an electrical connection with the substrate 12 is performed. Next, a step of applying a liquid resin (an epoxy-based thermosetting resin) to the upper surface of the substrate 12 so as to cover the semiconductor chip 13 is performed.

This step is performed by multi-point application (or scanning application) of a required amount of liquid resin from the upper surface side of the substrate 12 using, for example, a dispenser. Is gradually spread from the center side to the outside, and the edge of the four sides of the substrate 12 is kept in a state where the flow of the liquid resin is stopped.

Here, when the liquid resin is applied to the upper surface of the substrate 12 to spread the liquid resin, the apparent surface tension of the liquid resin becomes large when the edge of the liquid resin reaches the edge of the substrate 12. As a result, the edge portion of the substrate 12 does not easily overflow outside the edge portion of the substrate 12, and as a result, the edge portion of the substrate 12 serves to stop the flow of the liquid resin.

That is, referring to FIG. 1, as shown in FIG. 1 (a), when a certain amount of the liquid resin B is applied to the upper surface of the substrate A, the contact point P1 at the end thereof is located on the substrate A. In this case, the swelling angle (contact angle) θ of the liquid resin B at the contact point P1 is: Rs = Rl cos θ + Rsl (1) (where Rs is the magnitude of the surface tension of the substrate A, and Rl is the liquid resin The magnitude of the surface tension of B, Rsl is the substrate A and the liquid resin B
(The magnitude of the surface tension at the interface with the surface) is established and stable. When the liquid resin B is further applied from the state shown in FIG. 1A, the liquid resin B spreads again until the same angle θ is obtained.

However, when the edge of the substrate A is viewed microscopically, as shown in FIG. 1B, it is considered that a so-called R is provided. When the contact point P2 reaches the edge of the substrate A, the tangential direction of the contact point P2 changes from a horizontal state to an inclined shape that descends outward, and the direction of the surface tension (Rs, R1, Rsl) changes. ,
In this state, the balance is stabilized where the above equation (1) is satisfied. Since the R portion at the edge of the substrate A is very small, the influence of gravity is extremely small as compared with the surface tension and is considered to be almost negligible.

In this case, the substrate A as shown in FIG.
In the equilibrium state at the edge of the contact point P2
Of the liquid resin B with respect to the upper surface of the substrate A (ie, the apparent contact angle) θ ′ becomes larger than the angle θ shown in FIG. This means that when the edge of the liquid resin B reaches the edge of the substrate A, the liquid resin B does not easily overflow from the edge of the substrate A, and the coating amount is reduced. Even if the apparent contact angle with respect to the upper surface of the substrate A exceeds the angle θ, the apparent contact angle becomes
It will not overflow until you cross'.

Therefore, when the liquid resin is spread on the substrate 12, the edges of the four sides of the substrate 12 can be used as a stop for the flow of the liquid resin without providing a frame or the like for blocking the spread of the liquid resin. Thus, the step of applying the liquid resin can be performed without the liquid resin overflowing from the upper surface of the substrate 12.

Thereafter, a step of curing the applied liquid resin is performed. In this step, the substrate 12 is placed in a heating furnace in which the internal temperature is maintained at, for example, 150 to 180 ° C.
Is carried out and left for about several hours, and the liquid resin is cured to form the sealing resin layer 15. Note that the sealing resin layer 15 thus formed has a sufficiently high flatness on the upper surface, and has excellent vacuum suction properties as the semiconductor component 11 and also has excellent appearance. Thereafter, the solder bumps 14 are formed on the back surface of the substrate 12.
Is performed, and the semiconductor component 11 is obtained.

As described above, according to the present embodiment, attention is paid to the fact that the edge of the substrate 12 serves to stop the flow of the liquid resin, and the sealing is performed with the edge of the substrate 12 being the stop for the liquid resin. Since the stop resin layer 15 is provided, unlike the conventional case in which a resin frame serving as a wall for preventing the liquid resin from flowing out is formed, a simple configuration is required, but the liquid resin is sealed out of the sealing range. This has an excellent practical effect that the outflow of water can be prevented. Further, in the present embodiment, the application step of the liquid resin is performed by multi-point application or scanning application, so that the application step of the liquid resin can be performed more efficiently than in the case of single-point application. Can also be obtained.

In the above embodiment, all the four edges of the substrate 12 are made to stop the flow of the liquid resin.
May be configured so that at least a part of the edge portion of the edge portion serves as a stopper for the liquid resin.

(2) Second and Third Embodiment FIGS. 3 and 4 show a second embodiment (corresponding to claim 2) of the present invention. As shown in FIG. 3, this embodiment is different from the first embodiment in that when the sealing resin layer 17 is provided in a state where the edge of the substrate 16 is kept from flowing the liquid resin, the substrate An edge portion 16 of the liquid resin 16 serving as a flow stopper is formed in an acute angle with a reverse taper toward the back surface side. According to this, the effect of preventing the liquid resin from overflowing at the edge of the substrate 16 can be further enhanced.

FIG. 4 shows the edge of the substrate 16 microscopically, and the edge of the substrate 16 is formed at an acute angle.
Again, a so-called R is attached to the tip. Here, the liquid resin B spreads over the upper surface of the substrate 16 and
If the influence of gravity is ignored even at the edge of the liquid resin B, it is considered that the liquid resin B can be additionally applied until the end of the liquid resin B wraps around to the lower surface side to reach the state of the contact point P3. Can be

In this state, the surface tension (Rs, Rl, R
The direction of (sl) changes by 90 degrees or more compared to the case where the contact point P1 is on the upper surface of the substrate 16 (FIG. 1A). Of the liquid resin B can be considerably increased, so that even if a considerably large amount of the liquid resin B is applied, it does not overflow. 4 is exaggerated because of the influence of gravity. However, a certain high effect can be obtained as compared with the state shown in FIG. This is effective when the surface tension Rl is large.

FIG. 5 shows a third embodiment of the present invention.
). This embodiment differs from the first embodiment in that a flow stopper 18 having a lower surface tension than the substrate 12 is provided at the edge of the substrate 12. The flow stopper 18 is made of, for example, Teflon or the like, and is provided on the end surface of the substrate 12 by applying a liquid material or pasting a tape-shaped material.

According to this, the surface tension of the substrate 12 at the point where the edge of the liquid resin comes into contact, that is, Rs of the above-described formula (1)
Becomes smaller, and consequently, cos θ becomes smaller, and the angle θ at the time of balancing can be increased. As a result, the swelling angle (the apparent contact angle) θ ′ of the liquid resin at the contact point with respect to the upper surface of the substrate 12 can be further increased, and the effect of preventing the liquid resin from overflowing can be further enhanced. You can do it.

(3) Fourth Embodiment Referring to FIG. 6, a fourth embodiment of the present invention will be described.
6 and 7). FIG. 6 illustrates a main configuration of a semiconductor component (COB) 21 according to the present embodiment.
The semiconductor component 21 is obtained by mounting a semiconductor chip (not shown) on a large-sized substrate 22 made of, for example, a printed board, and partially providing a sealing resin layer 23 for sealing the semiconductor chip on the substrate 22. It is configured.

At this time, an island-shaped step portion 24 which is higher than the surrounding portion is formed in the region (square region) where the sealing resin layer 23 is formed on the upper surface of the substrate 22.
The semiconductor chip is mounted on the island-shaped step portion 24, and the edge of the sealing resin layer 23 coincides with the edge of the island-shaped step portion 24. In the present embodiment, the island-shaped steps 24
Is made of a solder resist, and its height (the thickness of the solder resist applied) is, for example, 30 to 50 μm.

In manufacturing the semiconductor component 21, the island-shaped step portion 24 is formed in advance by printing and applying the solder resist to the formation region of the sealing resin layer 23 when printing the solder resist at the time of manufacturing the substrate 22. Keep it. Then, after a semiconductor chip is mounted on the island-shaped step portion 24 of the substrate 22 and required electrical connection is made, the island-shaped step portion 24
The liquid resin is applied on the top so as to cover the semiconductor chip.
The process is performed in a state where the edges of the four sides of No. 4 are made to stop the flow of the liquid resin.

In this case, similar to the first embodiment and the like,
Since the liquid resin that spreads out does not easily overflow outside the edge of the island-shaped step portion 24, the edge portion of the island-shaped step portion 24 functions as a flow stopper for the liquid resin. With a relatively simple configuration,
This can prevent the liquid resin from flowing out of the sealing range. In particular, in the present embodiment, since the island-shaped steps 24 are formed of a solder resist, the step of forming the island-shaped steps 24 can be simplified.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view for explaining the operation of the present invention, in which surface tension when a contact point of an edge of a liquid resin is located on an upper surface of a substrate (a) and when it is located on an edge of the substrate (b). Vertical sectional view showing the relationship between

FIG. 2 is a longitudinal sectional front view of the semiconductor component according to the first embodiment of the present invention.

FIG. 3 shows a second embodiment of the present invention and is a longitudinal sectional front view of a main part of a semiconductor component.

FIG. 4 is an enlarged vertical sectional view for explaining the operation.

FIG. 5 is a longitudinal sectional front view of a main part of a semiconductor component according to a third embodiment of the present invention.

FIG. 6 is a longitudinal sectional front view of a main part of a semiconductor component according to a fourth embodiment of the present invention.

FIG. 7 shows a conventional example and is equivalent to FIG.

FIG. 8 is a diagram corresponding to FIG. 2 showing another conventional example.

[Explanation of symbols]

In the drawings, 11, 21 are semiconductor components, 12, 16, 22 are substrates, 13 is a semiconductor chip, 15, 17, and 23 are sealing resin layers, 18 is a flow stopper, 24 is an island-shaped step, and A is a substrate. ,
B indicates a liquid resin.

Claims (8)

[Claims] Claims: 1. A semiconductor chip is mounted on a substrate, and a sealing resin layer for sealing the semiconductor chip is provided by applying and curing a liquid resin on the substrate. A semiconductor component, wherein the sealing resin layer is provided in a state where at least a part of the edge of the substrate is kept from flowing the liquid resin. 2. The semiconductor component according to claim 1, wherein an edge portion of the substrate serving as a stopper for the liquid resin is formed in an acute angle with a reverse taper toward a back surface side. 3. The semiconductor according to claim 1, wherein a flow stopper having a surface tension smaller than that of the substrate is provided at an edge portion of the substrate at which the liquid resin stops flowing. parts. 4. A method for mounting a semiconductor chip on a substrate, and applying a liquid resin on the substrate and curing the resin to provide a sealing resin layer for sealing the semiconductor chip. A semiconductor component, wherein a sealing resin layer forming region on the substrate has a stepped shape higher than a peripheral portion thereof. 5. A method for manufacturing a semiconductor component comprising mounting a semiconductor chip on a substrate and providing a sealing resin layer for sealing the semiconductor chip, wherein the semiconductor chip is mounted on the substrate. A step of applying a liquid resin on the substrate so as to cover the semiconductor chip, and a step of curing the liquid resin. The step of applying the liquid resin includes at least an edge of the substrate. A method of manufacturing a semiconductor component, wherein the method is performed in a state in which a liquid resin is stopped in a part. 6. A method for manufacturing a semiconductor component comprising mounting a semiconductor chip on a substrate and providing a sealing resin layer for sealing the semiconductor chip, comprising: forming a sealing resin layer on the substrate. A step of forming an island-shaped step portion higher than a peripheral portion in the region, a step of mounting a semiconductor chip on the island-shaped step portion, and applying a liquid resin on the island-shaped step portion so as to cover the semiconductor chip. The method includes a step of applying and a step of curing the liquid resin, wherein the step of applying the liquid resin is performed in a state in which an edge of the island-shaped step portion is set to stop the flow of the liquid resin. Of manufacturing semiconductor components. 7. The method according to claim 6, wherein the island-shaped step is formed by applying a solder resist to a sealing resin layer forming region on the substrate. 8. The method according to claim 5, wherein the step of applying the liquid resin is performed by multi-point application or scanning application.