JP2001237257A - Semiconductor device and method of mounting the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device of high connection reliability and a method of manufacturing the same by using one-point dispense coating, which is a cheap and high-productivity resin-supply method, in LSI mounting in which a pressure-welding method is used. SOLUTION: By arranging a plurality of solder-resist protuberances 2 inside a mounting pad, applying on-point coating of sealing resist to a position at the center with respect to the arrangement of the plurality of the solder-resist protuberances 2, and mounting a semiconductor device on a circuit substrate 1 by applying heat and pressure, each top of the solder-resist protuberances 2 formed on the peripheral parts of the circuit substrate 1 is penetrated by the sealing resist, and fillets of equal amount for each are formed in the inside.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a method for manufacturing the semiconductor device, and more particularly, to a semiconductor device uniformly filled with a sealing resin and a method for mounting the same.

[0002]

2. Description of the Related Art Conventionally, a pressure welding method has been known as a method for mounting a bare chip. This method does not require supply of a bonding material such as solder or conductive resin, as disclosed in, for example, Japanese Patent Publication No. 27770821 “Method and mounting of semiconductor device”. The pad is electrically connected only by mechanical contact by the contraction force of a sealing resin filled between the LSI and the substrate.

In this method, first, a sealing resin is supplied to an LSI mounting portion on a substrate. The LSI is mounted thereon, heated and pressed, and the sealing resin is cured to obtain connection between the electrodes. In the pressure welding method, a sealing resin supplied on a substrate in advance is filled with a gap between the LSI and the substrate while being spread by the LSI. In this way, it is difficult to form the fillet by spreading the sealing resin evenly in the gap of the LSI, and the shape is greatly affected by the method of supplying the sealing resin.

[0004] The supply method is roughly divided into a method using a dispenser and a printing method. Methods using a dispenser include one-point application, multi-point application, multi-point nozzle application, and the like. The one-point application is a method in which a required amount is applied at once to the center of the mounting portion, and is most commonly used. Such one-point coating is a method which is inexpensive as compared with a method using a plurality of dispensers and has a short coating time.

[0005]

However, when a high-viscosity resin is used as a sealing resin or when a fast-curing resin (a conventional thermosetting resin takes more than one minute at 200 ° C., When the resin is cured in about half of the curing time or less), it is spread out while the shape of the resin applied on the substrate remains, and then sealed by applying the temperature to the curing temperature When the resin is cured, the resin is cured in a state where the shape of the sealing resin generated at the time of application remains. In the usual one-point coating, the supplied sealing resin becomes semi-spherical on the substrate due to surface tension, and such a semi-spherical sealing resin is generally replaced with a square LSI.
, The sealing resin spreads out in a circular shape.
A fillet having a shape in which the sealing resin is insufficient at the corner of I is obtained.

The conventional solder resist pattern of the LSI mounting portion on the substrate has a typical shape shown in FIGS. In such a conventional pattern, no resistance is given to the flow of the sealing resin supplied on the substrate at the time of mounting the LSI. Therefore, when the LSI descends to be mounted on the substrate, it is pushed by the LSI and spreads in a circular shape. As a result, the sealing resin is insufficient at the corners of the LSI, and is cured while holding the sealing resin, resulting in a mounted body having no sealing resin at the corners. Since the volume of the sealing resin used in the present invention shrinks when it is cured, the bump electrodes come into close contact with the mounting pads, and complete electrical connection between the circuit board and the LSI can be achieved. Therefore, if the sealing resin is insufficient at at least one of the corners as described above, a portion where electrical connection cannot be established between the circuit board and the LSI, or even if electrical connection can be established during production, but thereafter, disconnection occurs. It is likely to be in a state.

For this reason, for example, Japanese Patent Application Laid-Open No. 11-3075
As described in Japanese Patent Publication No. 84, “Method of Manufacturing Semiconductor Device”, an LSI is heated in a stepwise manner so that a relatively low temperature region (1
(About 00 ° C.) by temporarily holding this temperature to lower the viscosity of the sealing resin to spread the sealing resin evenly under the LSI, and then raise the temperature to cure the sealing resin. Have been. By using this method, LS
A fillet can be formed evenly at each edge of I.

However, if a resin that cures in a shorter time is employed to improve the productivity, it is difficult to secure a stage where the resin spreads under the LSI, and as a result, the shape of the fillet is affected. In particular, when the one-point coating method is used, the corner portion is not filled with the sealing resin. That is, in such a case, since the sealing resin spreads in a circular shape under a square LSI, for example, the only solution is to increase the amount of the sealing resin sufficient at the corners. The amount of fillets on the sides becomes very large, and the MCM (multi chip mod
ule), there is a risk of interference with an adjacent LSI.

In order to solve such a problem, after applying by a multi-point coating method in which coating is repeated using a dispenser instead of one-point coating, the LSI is placed on a substrate and the sealing resin is spread. There is a way. By adopting this method, the shortage of resin at the corners observed in one-point coating is eliminated, and the shape of the fillet is improved. However, when this method is employed, since one-point application by a dispenser is repeated a plurality of times, there is a problem that the application time is lengthened and productivity is reduced as a whole.

[0010] Further, if a multi-point nozzle coating method in which a plurality of nozzles are provided and applied is used, a nozzle provided with a plurality of discharge ports at a point position to be applied is used. And the productivity of the semiconductor device does not decrease. However, the multi-point nozzle used in the multi-point nozzle coating method requires a new multi-point nozzle separately every time the shape of the LSI is changed, and the multi-point nozzle is expensive, which affects the production cost. There is a point.

As a second coating method without using a dispenser, a printing method for printing a required amount is also known. In the present method, it is possible to supply according to the shape of the LSI, and it does not spread in a circle as in single point application by dispensing. However, since this supply step needs to be performed before the LSI mounting step, a resin having a short pot life cannot be used. In addition, the substrate side is often heated so that heat from the LSI side does not escape during the mounting process, and there is a problem that the curing reaction of the supplied resin proceeds by this heat.

As described above, in consideration of cost, productivity, etc., single-point application using a dispenser is advantageous for resin supply, but there is a problem in fillet formation.

SUMMARY OF THE INVENTION An object of the present invention has been made in view of the above-mentioned problems of the prior art, and corrects incomplete conduction between a circuit board and an LSI due to insufficient or excessive sealing resin. It is an object of the present invention to provide a semiconductor device capable of stabilizing the performance of a semiconductor device after manufacturing and to provide a mounting method of such a semiconductor device. The present invention also provides a semiconductor device mounting method using a pressure welding method, which is a low-cost, high-productivity resin supply method and uses a single-point application by dispensing to provide a semiconductor device mounting method with high connection reliability. Is to do.

[0014]

According to a first aspect of the present invention, there is provided a semiconductor device, wherein a plurality of solder resists are provided between substantially parallel mounting pad rows, and the solder resist has a plurality of sealing resins. When the semiconductor device having the protruding electrodes is mounted, the semiconductor device is provided so as to spread almost evenly to the corners of the mounting pad row.

According to a second aspect of the present invention, a plurality of solder resists are provided between mounting pad rows provided substantially in parallel, and the plurality of solder resists are transferred to a corner portion of the mounting pad row. It is characterized in that the sealing resin before curing is divided so as to flow substantially evenly by mounting a semiconductor device having a plurality of projecting electrodes.

According to a third aspect of the present invention, there is provided a semiconductor device according to the third aspect of the present invention, wherein between the mounting pad rows provided substantially in parallel, an end angle of the mounting pad row is in an angular relationship with the end. A solder resist is provided by dividing or forming a groove portion up to the vicinity of the end of one of the mounting pad rows, and the mounting pad row is formed by mounting a semiconductor device having a sealing resin having a plurality of projecting electrodes. Characterized in that it flows almost evenly to the corners of.

According to a fourth aspect of the present invention, a plurality of solder resists are provided between substantially parallel mounting pad rows, and the solder resist is hardened to the corners of the mounting pad rows. It is characterized by being divided in a diagonal direction so that the previous sealing resin flows.

According to a fifth aspect of the present invention, there is provided a semiconductor device mounting method, wherein a plurality of protrusions are applied after a single point application is applied to the vicinity of the center of the mounting portion on which the mounting pads on the substrate are formed, and the sealing resin is applied. A method of mounting a semiconductor device having a plurality of protruding electrodes thereon, the method comprising: mounting a semiconductor device having electrodes thereon, and heating and pressing the semiconductor device to mount the semiconductor device on the substrate. A plurality of raised solder resists are provided in the mounting pad row provided substantially in parallel so that the sealing resin flows evenly to the peripheral portion of the device, thereby forming a fillet.

According to a sixth aspect of the present invention, in the method for mounting a semiconductor device according to the fifth aspect, when the semiconductor device is mounted on the substrate, the sealing resin spreads to the vicinity of each vertex of the semiconductor device. Thus, the rod-shaped solder resist is provided inside the mounting pad row on the substrate.

According to a seventh aspect of the present invention, in the semiconductor device mounting method according to the fifth aspect, a solder resist is divided and provided inside the mounting pad row on the substrate, and the semiconductor device is mounted on the substrate. Each of the vertices of the semiconductor device when mounted on the semiconductor device is sealed substantially evenly so that the sealing resin reaches the end of the mounting pad row on the substrate side which is mounted substantially in parallel. It is characterized in that the solder resist through which the resin flows is provided.

According to an eighth aspect of the present invention, there is provided the semiconductor device mounting method according to the fifth aspect, wherein the solder resist is provided by dividing or forming a groove inside the mounting pad row on the substrate. The sealing resin before curing is moved to the corner of the LSI by placing the LSI.
Characterized in that it flows almost evenly to the corners of.

According to a ninth aspect of the present invention, there is provided a semiconductor device mounting method according to any one of the fifth to eighth aspects, wherein the thickness of the plurality of solder resists is provided in a range of 10 to 30 μm. I do.

According to a tenth aspect of the present invention, there is provided a semiconductor device mounting method according to any one of the fifth to ninth aspects, wherein the sealing resin has a curing shrinkage rate larger than a thermal expansion coefficient after curing. It is characterized by using a mold quick-setting resin.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the present invention, a solder resist 2 is divided and provided in a mounting pad row composed of a plurality of mounting pads 3, 3,... Provided substantially in parallel on a substrate. It is characterized by being. Using such a substrate, an LSI having a bump electrode (bump electrode) is fixed by thermosetting a sealing resin and mounted to manufacture a semiconductor device. When the semiconductor device is mounted on the substrate, the sealing resin is sealed up to each vertex of the semiconductor device and to an end of the mounting pad row on the substrate side which is mounted substantially in parallel. It is preferable to divide the solder resist or to form a groove so as to provide the solder resist in which the sealing resin flows almost uniformly so that the sealing resin spreads.

Hereinafter, a semiconductor device of the present invention and a method of mounting the device will be described with reference to the drawings. FIG. 4 is a cross-sectional view of the flip-chip mounting process according to the embodiment of the present invention, which is cut by mounting pads on a circuit board.

(A) LSI 4 having bump electrodes 5 formed thereon
Is shown. Here, the material of the bump electrode 5 is not limited, but a material that is deformed on the mounting pads 3 on the circuit board 1 by a load applied when mounting the LSI 4 is preferable. In this embodiment, Au is used as the material. Further, it is preferable that the shape of the bump electrode 5 is formed such that the tip of the tail is pointed.

FIG. 2B shows an unmounted circuit board 1. Although the type of the base material of the circuit board 1 used in the present invention is not particularly limited, a printed wiring board manufactured by a build-up method is used in the present embodiment. FIG. 1 shows a solder resist pattern according to an embodiment of the present invention. Although the material of the solder resist 2 is not limited, a photosensitive liquid resist is used in the present embodiment.
As shown in FIG. 1, a pattern made of the solder resist 2 is formed in the LSI 4 mounting area so as to be resistant to the flow of the sealing resin 6. The thickness of the solder resist 2 is preferably 10 to 30 μm on the substrate and the pattern of the circuit board 1, and in the present embodiment, 30 μm on the substrate,
The pattern was 20 μm.

Next, as shown in FIG.
The sealing resin 6 is supplied to the center of the upper mounting portion. The supply method used in the present invention is a one-point coating method using a known dispenser. As the sealing resin 6, an epoxy-based thermosetting fast-curing resin having a curing shrinkage value larger than the thermal expansion coefficient of the cured sealing resin was used. The encapsulating resin 6 completes curing at 200 ° C. for about 30 seconds (curing at 220 ° C. for 1 second: curing at a tool temperature of 260 ° C. for 1 second). In the present invention, further, the curing condition of the sealing resin is 200 ° C. for about 10 seconds, for example, 1 to 1.
An epoxy resin in a range of 10 seconds, particularly about 5 seconds can be used as the sealing resin. The sealing resin 6 is supplied onto the circuit board 1 by the one-point coating method, and the applied sealing resin 6 has a shape close to a semicircular sphere due to the surface tension of the resin.

Subsequently, as shown in (d), the bump electrodes 5 of the LSI 4 heated to a predetermined temperature are aligned with the mounting pads 3 on the circuit board 1 heated to a predetermined temperature. The temperature at which the LSI 4 and the circuit board 1 are heated may be lower than the temperature at which the sealing resin is cured, and is not particularly limited as long as the temperature is such a temperature. The temperature is higher than room temperature (30 ° C.), preferably from a temperature lower by 80 ° C. than the curing temperature to about 55 ° C. In this embodiment, the temperature is set to 80 ° C.

Finally, as shown in (e), the LSI 4 is mounted on the circuit board 1, and the LSI 4 is pressurized and heated. Here, the amount of pressurization is a pressure at which all the bump electrodes 5 come into contact with the mounting pads 3 and are crushed to a predetermined amount. In the present embodiment, the pressure per bump electrode 5 is 30 g. This pressure crushes the bump height from 100 μm to 60 μm. Heating was performed at 200 ° C on the LSI 4 side and 80 ° C on the circuit board 1 side.
The holding time was 30 seconds. At this time, as shown in FIGS. 1 to 3, the direction of the flow of the sealing resin is given by the solder resist 2 formed on the circuit board 1 at the corners as shown in FIGS. To the corner.

According to the above method, as shown in FIG. 3 (f), a uniform amount of fillet is formed around the LSI 4, and a highly reliable mounting structure can be obtained.

In the above-described embodiment, the case where the shape of the solder register has the pattern shown in FIG. 1 has been described as an example. However, as another embodiment of the solder resist, as shown in FIGS. It can also be a pattern. By using the solder resist pattern as shown in FIGS. 1 to 3, it is possible to give the direction of flow of the resin when mounting the LSI such that it is guided to the corners of the LSI 4. Note that in FIGS. 1 (1), 2 (1) and 3 (1), the directionality of the flow of the sealing resin is indicated by arrows.

In the solder resist pattern of the present invention, the solder resist 2 is provided outside the mounting pad 3 so as to surround the mounting pad 3. The solder resist 2 is provided inside the mounting pad 3 in a predetermined arrangement and shape in order to give a flow toward the corner of the LSI 4 to the flow of the solder.

In the embodiment shown in FIGS. 1 and 2, mounting pads 3 are provided in four directions in parallel with the inner side of the solder resist 2 formed on the peripheral portion of the circuit board 1. In the embodiment shown in FIG. 1, a rectangular solder resist 2 is provided inside each of the mounting pads 3 so as to be parallel to the mounting pads 3. In the embodiment shown in FIG. 2, the mounting pad 3 side is a lower bottom, the center side of the circuit board 1 is an upper bottom, and the lower bottom is longer than the upper bottom and the upper and lower bottoms are the mounting pads. A solder resist 2 having a trapezoidal shape parallel to 3 is provided for each mounting pad 3.

In the embodiment shown in FIG. 3, mounting pads 2 are provided in two opposing directions. Inside these mounting pads 2, the mounting pad 3 side is a lower bottom, the center side of the circuit board 1 is an upper bottom, and the lower bottom is longer than the upper bottom and the upper and lower bottoms are parallel to the mounting pad 3. A solder resist 2 having a trapezoidal shape is provided for each mounting pad 2, and a triangular shape in which the outside of the circuit board 1 is a bottom and the center side of the circuit board 1 is a vertex in two other opposing directions. A solder resist 2 is provided for each of the two directions.

With the solder resist pattern thickness as in the above-described embodiment, the resin can naturally get over this pattern in the process of spreading, but there is a difference in the ease of flow when compared with a place where this pattern does not exist. Come. If the direction of the corner of the LSI 4 is given to this flow by utilizing the ease of the flow, the LSI can be mounted at the time of mounting the LSI.
The same amount of resin as that at the center of the I4 side can be obtained at the corner of the LSI.

Although the above-described embodiment is a preferred embodiment of the present invention, the present invention is not limited to this embodiment. When the device is mounted on the substrate, the sealing resin is substantially evenly distributed so as to reach each vertex of the semiconductor device and the end of the mounting pad row on the substrate side which is mounted substantially in parallel. The present invention can be implemented as long as the LSI mounting portion has a solder resist having such a shape as to give a sealing resin flowing direction.

[0038]

As is apparent from the above description, according to the present invention, in the LSI mounting by the pressure welding method, the mounting process time and the resin supply amount can be increased without using a special and expensive resin supply method. A highly reliable connection can be obtained by one-point application without the need.

The reason is that the present invention makes it possible to control the flow of the resin supplied between the LSI and the mounting board, and as a result, it is possible to make the fillet amount around the chip uniform, which was difficult with one-point coating. It is possible.

[Brief description of the drawings]

FIG. 1 is a view showing a solder resist pattern according to a first embodiment of the present invention, wherein FIG.
It is sectional drawing in the A line.

FIG. 2 is a view showing a solder resist pattern according to a second embodiment of the present invention.
It is sectional drawing in the B line.

FIG. 3 is a view showing a solder resist pattern according to a third embodiment of the present invention.
It is sectional drawing in the C line.

FIG. 4 is a diagram illustrating a mounting process of the semiconductor device according to the embodiment of the present invention.

FIG. 5 is a diagram showing a first example of a conventional solder resist pattern.

FIG. 6 is a view showing a second example of a conventional solder resist pattern.

FIG. 7 is a view showing a third example of a conventional solder resist pattern.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Circuit board 2 Solder resist 3 Mounting pad 4 LSI 5 Bump electrode 6 Sealing resin 7 Pulse heating tool

Claims (10)

[Claims] A plurality of solder resists are provided between mounting pad rows provided substantially in parallel, and the solder resist is used for mounting the semiconductor device when a semiconductor device having a plurality of projecting electrodes is mounted on a sealing resin. A semiconductor device provided so as to be substantially evenly spread to a corner portion of a pad row for use. 2. A plurality of solder resists are provided between mounting pad rows provided substantially in parallel, and the plurality of solder resists are divided into a plurality of sealing resin before curing to a corner portion of the mounting pad row. A semiconductor device, wherein a semiconductor device having a protruding electrode is mounted so as to be divided so as to flow substantially uniformly. 3. An end portion of another mounting pad row which has a positional relationship between the mounting pad row provided substantially in parallel and an odd angle from the end of the mounting pad row. Up to the vicinity, divided or formed a groove portion to provide a solder resist, so that the sealing resin flows substantially evenly to the corner portion of the mounting pad row by mounting a semiconductor device having a plurality of projecting electrodes. A semiconductor device characterized by the following. 4. A plurality of solder resists are provided between mounting pad rows provided substantially in parallel with each other, and the solder resist flows into the corners of the mounting pad rows so that the sealing resin before curing flows into the corners of the mounting pad rows. A semiconductor device which is divided in a diagonal direction. 5. A semiconductor device having a plurality of protruding electrodes is placed on the substrate at one point near the center of the mounting portion on which the mounting pads are formed, and a sealing resin is applied. A mounting method of mounting the semiconductor device on the substrate, wherein the semiconductor device having the plurality of protruding electrodes is placed, and the sealing resin flows uniformly to a peripheral portion of the semiconductor device. A method of mounting a semiconductor device, comprising: forming a fillet by providing a plurality of raised solder resists in the mounting pad row provided substantially in parallel as described above. 6. A rod-shaped inside of the mounting pad row on the substrate, such that when the semiconductor device is mounted on the substrate, the sealing resin spreads to the vicinity of each vertex of the semiconductor device. The method for mounting a semiconductor device according to claim 5, wherein a solder resist is provided. 7. A solder resist is separately provided inside the mounting pad row on the substrate, and is substantially parallel to each vertex of the semiconductor device when the semiconductor device is mounted on the substrate. 6. The solder resist according to claim 5, wherein the sealing resin flows substantially evenly so that the sealing resin reaches the end of the mounting pad row on the substrate placed on the substrate. Semiconductor device mounting method. 8. A solder resist is provided by dividing or forming a groove on the inside of the mounting pad row on the substrate, and the sealing resin before hardening is applied to the LSI until a corner of the LSI is formed. 6. The method for mounting a semiconductor device according to claim 5, wherein the mounting causes the semiconductor device to flow substantially evenly to a corner portion of the LSI. 9. The thickness of the plurality of solder resists,
The method for mounting a semiconductor device according to claim 1, wherein the semiconductor device is provided in a range of 10 to 30 μm. 10. The thermosetting resin according to claim 5, wherein the sealing resin is a thermosetting fast-curing resin having a curing shrinkage greater than a thermal expansion coefficient after curing. Semiconductor device mounting method.