JPH1131704A - Manufacture of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and inexpensively manufacture a semiconductor device whose surface made of sealing resin is flat. SOLUTION: Sealing resin 4 is applied to the entire face of the part of a base substrate 1 on which a bare chip 2 is mounted, the thickness is made almost uniform through the surface tension, and then the sealing resin 4 is heated and hardened. Then, the base substrate 1 is divided into each unit block 1b along a V groove 1a formed at the base substrate 1, so that a semiconductor device can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method of manufacturing a semiconductor device in which a package base substrate on which a bare chip of a semiconductor integrated circuit is mounted is sealed with a resin.

[0002]

As a prior art of a method of manufacturing a semiconductor device, there is known a method of manufacturing a semiconductor device. There is a potting method in which a resin is applied to the surface. In this potting method,
Since the unit partition area of the base substrate is relatively small, the surface of the applied resin hardly has a flat portion, and the resin has a substantially convex shape. For this reason, when the semiconductor device completed by dividing the base substrate coated with the resin is surface-mounted on the circuit board, there has been a problem that the suction performance of the vacuum suction nozzle of the mounting device is not good.

In order to solve such a problem, a molding method is used in which a resin is press-fitted in a state in which a base substrate on which a bare chip is mounted is put in a mold, so that the resin is coated flat in each unit section. Is now available. However, in this molding method, there is a problem that the production of the mold is very costly, and in addition, the process becomes complicated.

Japanese Patent Application Laid-Open No. 58-135 discloses that a region such as a memory cell formed on a semiconductor chip is protected by a silicone film under a resin mold in order to protect α-rays existing in nature. In order to make the surface of the silicone film flat in such a case, before the applied silicone film is cured, a material which achieves the purpose by disposing an insulating resin thin film of another member on the surface of the silicone film is disclosed. Have been.

Although the technique disclosed in Japanese Patent Application Laid-Open No. 58-135 seems to be applicable to the formation of a sealing resin as it is, the use of a separate member also increases the cost and the number of steps. Exists as an issue without being solved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method of manufacturing a semiconductor device which can easily and inexpensively manufacture a flat surface of a sealing resin.

[0007]

According to a method of manufacturing a semiconductor device according to the present invention, a sealing resin is applied over the entire mounting surface of a package base substrate on which a bare chip of a semiconductor integrated circuit is mounted. , By the action of surface tension,
Since the thickness of the applied sealing resin becomes substantially uniform, the surface of the sealing resin of each semiconductor device divided along the dividing groove formed in the base substrate after the sealing resin is cured is flat. Formed. Therefore, the molding method and
For example, when mounting on a circuit board by a mounting apparatus having a nozzle for performing vacuum suction without using an expensive mold or another member as in the technique disclosed in Japanese Patent Application Laid-Open No. 8-135, suction by the nozzle is used. A semiconductor device having good performance can be manufactured easily and at low cost.

According to the method of manufacturing a semiconductor device of the present invention, a thermosetting sealing resin is applied to the entire package mounting substrate on which the bare chip of the semiconductor integrated circuit is mounted. In the hardened state in the latter half, the jig is pressed against the surface of the sealing resin at a position corresponding to the divisional groove formed on the base substrate to form an auxiliary divisional groove. Therefore, by forming the auxiliary division grooves on the surface of the sealing resin, the step of dividing the base substrate into unit sections can be performed more easily.

According to the method of manufacturing a semiconductor device of the present invention, since the jig for forming the auxiliary dividing groove is heated, the curing of the sealing resin is accelerated, and the time required for the curing is shortened. Can be.

According to the method of manufacturing a semiconductor device of the present invention, the depth of the auxiliary dividing groove formed on the surface of the sealing resin is substantially equal to the thickness of the applied sealing resin.
The step of dividing the base substrate into unit sections can be performed more easily.

According to the method of manufacturing a semiconductor device of the present invention, the shape of the auxiliary dividing groove formed on the sealing resin surface is such that the dividing end of the sealing resin for each unit section has a curved shape. Since the sealing resin is formed, the volume of the sealing resin becomes smaller as approaching the divided end, as compared with the case where the divided end has a linear shape.

Therefore, it is possible to reduce the thermal expansion or thermal shrinkage of the sealing resin near the divided end when the temperature changes, and to reduce the stress near the joint surface between the sealing resin and the base substrate at the divided end. Therefore, it is possible to prevent the sealing resin from peeling off from the base substrate at the bonding surface, and to improve the yield of the semiconductor device.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a plan view showing a state in which a bare chip and other components of a semiconductor integrated circuit are mounted on a base substrate. The base substrate 1 is made of, for example, glass epoxy or alumina having a thickness of 0.5 mm, and the substrate dimensions are about 40 mm long × 55 mm wide. The base substrate 1 has six pieces as an example, and is divided into six unit sections 1b by a dividing V-groove (divided groove portion) 1a formed by a cutter or the like. The size of each unit section 1b is 15 mm square.

The six unit sections 1b are arranged in 2 × 3 rows, and the periphery of the base substrate 1 has a width of 5 mm which is used as a holder when dividing into each unit section 1b as described later. Are formed. On each unit section 1b, a bare chip 2, and chip components 3 such as resistors and capacitors are mounted. The bare chip 2 has a semiconductor integrated circuit formed on its surface, and is connected to a wiring pattern formed on the base substrate 1 by bonding wires 2a.

FIG. 1 is a cross-sectional view showing a state where a sealing resin 4 is applied by a dispense method to a component surface (a mounting surface of the bare chip 2 and the like) of the base substrate 1 shown in FIG. The sealing resin 4 is made of a thermosetting epoxy resin, and is applied so as to have a thickness of about 1.0 mm over the entire component surface of the base substrate 1.

That is, when the sealing resin 4 is applied over the entire component surface of the base substrate 1, the thickness of the applied resin becomes substantially uniform due to the effect of the surface tension of the sealing resin 4. Also,
The depth dimension of the V-groove 1 a formed on the front and back of the base substrate 1 is about １ ／ of the thickness dimension of the base substrate 1.

The base substrate 1 to which the sealing resin 4 has been applied is
It is carried into a heating furnace or the like and heated to cure the sealing resin 4. As the heating conditions, for example, 1
It is about 4 hours at 50 degrees. When the sealing resin 4 is cured, the base substrate 1 is moved along the V-groove 1a into each unit section 1b.
Each semiconductor device 5 is divided as shown in FIG.
Is formed. In addition, the method of division may be such that a stress is applied with the V-groove 1a as the center of division, and may be manually applied, or a jig or a dedicated device may be used.

As described above, according to the present embodiment, the sealing resin 4 is applied over the entire component surface of the base substrate 1 on which the bare chip 2 is mounted, so that the thickness of the applied resin is increased by the action of surface tension. After the dimensions are made substantially uniform and the sealing resin 4 is cured, the V-groove 1a formed in the base substrate 1 is formed.
The base substrate 1 is divided into the unit sections 1b along the line.

Therefore, the surface of the sealing resin 4 of each divided semiconductor device 5 is formed flat, so that the semiconductor device 5
Is mounted on a circuit board by a mounting device having a nozzle for performing vacuum suction, the suction property of the nozzle is improved, and the molding method and
The semiconductor device 5 having such good adsorbability can be easily and inexpensively manufactured without using an expensive mold or another member as in the technique disclosed in Japanese Patent Publication No. 35-35.

(Second Embodiment) FIGS. 4 to 6 show a second embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. Only the parts will be described. In the second embodiment, while the sealing resin 4 is applied to the base substrate 1 as shown in FIG. 1, heating is performed so that the sealing resin 4 is in a semi-cured state. Here, the “semi-cured state” refers to a state before the sealing resin 4 is completely cured.

For example, in the first embodiment, the sealing resin 4 is
Although it was completely cured by heating at 50 degrees for about 4 hours, in the second embodiment, the sealing resin 4 is heated to 100 degrees for 5 minutes to be in a semi-cured state.

Next, as shown in FIG. 4, the jig 6 is pressed from above onto the surface of the sealing resin 4 in a semi-cured state, so that the auxiliary V-groove is also formed on the surface of the sealing resin 4. (Auxiliary division groove) 4a is formed. FIG. 5 is a perspective view in which the jig 6 is turned upside down to partially show the shape of the cutting edge. In FIG. 5, the jig 6 has a triangular cutting edge.
The configuration is such that they are combined in a grid pattern so as to have a pitch of 15 mm in accordance with the position of the V groove 1a formed on the base substrate 1.

By pressing such a jig 6 against the surface of the sealing resin 4, auxiliary V-grooves 4 a corresponding to the positions of the V-grooves 1 a on the substrate 1 are collectively formed on the surface of the sealing resin 4. . Auxiliary V
The depth dimension of the groove 4a is, for example, about 0.3 mm. After that, similarly to the first embodiment, the sealing resin 4 is completely cured by heating at 150 ° C. for about 4 hours (or under a heating condition obtained by discounting a half-cured amount).
The semiconductor device 5 is manufactured by being divided into the unit sections 1b along the V-groove 1a and the auxiliary V-groove 4a.

As described above, according to the second embodiment, the sealing resin 4 is applied over the entire component surface of the base substrate 1 and the sealing resin 4 is semi-cured. By pressing the jig 6 against the surface of the sealing resin 4 at a position corresponding to the formed V-groove 1a, the auxiliary V
The groove 4a was formed at once. Therefore, the V groove 1a and the auxiliary V
The base substrate 1 can be more easily divided into the unit sections 1b along the grooves 4a.

In the second embodiment, as shown in FIG. 6, the depth of the auxiliary V-groove (auxiliary divided groove) 4a 'is set to be substantially equal to the thickness of the sealing resin 4. You may. By forming the auxiliary V-groove 4a 'in this manner, the base substrate 1 can be more easily divided into the unit sections 1b.

(Third Embodiment) FIGS. 7 to 9 show a third embodiment of the present invention. The same parts as those of the second embodiment are denoted by the same reference numerals, and description thereof will be omitted. Only the parts will be described. In the third embodiment, an auxiliary groove (auxiliary divided groove portion) 4b is collectively formed on the surface of the sealing resin 4 by using the jig 7 as in the second embodiment, but the shape of the auxiliary groove 4b is auxiliary. It is different from the V groove 4a. That is, as shown in FIG. 8, the shape of the cutting edge of the jig 7 is not triangular, but in FIG. 8, it has a curved shape (with a so-called R) that expands downward.

The jig 7 having such a cutting edge shape divides the sealing resin 4 of each unit section 1b according to the shape of the auxiliary groove 4b formed on the surface of the sealing resin 4 as shown in FIG. The shape of the end 4c is also curved. By forming the divided end portion 4c in such a shape, the following operation and effect can be obtained.

That is, in FIG. 7, since the divided end 4c has a curved shape, the volume of the sealing resin 4 is smaller than that of the second embodiment in which the shape of the divided end is linear. Becomes smaller as approaching the divided end 4c. Therefore, the stress accompanying the thermal expansion or thermal contraction of the sealing resin 4 near the divided end 4c at the time of temperature change is reduced, and the vicinity of the joint surface 8 between the sealing resin 4 and the base substrate 1 at the divided end 4c is reduced. Since the thermal stress acting on the base member 1 is suppressed, it is possible to prevent the sealing resin 4 and the base substrate 1 from being separated from each other on the bonding surface 8.

Further, as the package size of the semiconductor device 5 increases, the degree of curvature of the divided end portion 4c increases as shown in FIG. At one end 8a, the inclination angle θ indicated by the curved shape of the divided end 4c is set to be small. With this setting, it is possible to reduce the effect of thermal stress that increases as the package size increases.

As described above, according to the third embodiment, the jig 7
Auxiliary groove 4b having a curved shape on the surface of sealing resin 4 by using
Is formed, the shape of the divided end 4c of the sealing resin 4 in each unit section 1b is curved, so that the heat acting near the joint surface 8 between the sealing resin 4 and the base substrate 1 when the temperature changes. The stress is reduced, and the sealing resin 4
Separation from the base substrate 1 can be prevented, and the yield of the semiconductor device 5 can be improved.

The present invention is not limited to the embodiment described above and shown in the drawings, and the following modifications or extensions are possible. In the second or third embodiment, the jig 6 or 7 may be pressed against the surface of the sealing resin 4 while being heated to an appropriate temperature. In this way,
The curing of the sealing resin 4 is accelerated, and the time required for curing can be reduced. Alternatively, the auxiliary V-groove 4a or the auxiliary groove 4b may be formed by heating under a heating condition of semi-curing the jig 6 or 7 without performing the heat treatment for semi-curing the sealing resin 4. By doing so, the sealing resin 4 can be semi-cured if the required time elapses while the jig 6 or 7 is pressed against the surface of the sealing resin 4, so that the semi-curing process is separately performed. There is no need to do it.

The V-groove 1a formed in the base substrate 1 may be provided only on the component surface or only on the surface opposite to the component surface.
The number of base substrates is not limited to six. In addition, the dimensions shown in each embodiment are merely examples, and can be implemented by appropriately changing the dimensions. The ears formed around the base substrate may be provided as needed. The shape of the jig is not limited to one in which a plurality of blades are combined in a lattice shape, and may be one formed of one blade. Such a jig is moved according to the size of a unit section of the base substrate. The auxiliary division groove may be formed by pressing the sealing resin a plurality of times.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a state where a sealing resin is applied over the entire bare chip mounting surface of a base substrate in a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a semiconductor device divided into unit sections.

FIG. 3 is a plan view of a base substrate on which a bare chip and other components are mounted.

FIG. 4 is a view corresponding to FIG. 1 showing a second embodiment of the present invention.

FIG. 5 is a perspective view showing the shape of the cutting edge of the jig by turning the jig upside down;

FIG. 6 is a view corresponding to FIG. 1 showing a modification of the embodiment.

FIG. 7 is a view corresponding to FIG. 1 showing a third embodiment of the present invention.

FIG. 8 is a diagram corresponding to FIG. 5;

FIG. 9 is a diagram illustrating an inclination angle θ indicated by a curved shape of a divided end portion at one end of a bonding surface between a sealing resin and a base substrate.

[Description of Signs] 1 is a base substrate, 1a is a V-groove (divided groove portion), 1b is a unit section, 2 is a bare chip, 4 is a sealing resin, 4a and 4a '
Denotes an auxiliary V-groove (auxiliary division groove), 4b denotes an auxiliary groove (auxiliary division groove), 4c denotes a division end, 5 denotes a semiconductor device, and 6 and 7 denote jigs.

Claims (5)

[Claims] 1. A bare chip of a semiconductor integrated circuit is mounted in each unit section, and a thermosetting sealing resin is provided on a base substrate for a package in which a division groove for dividing the unit section is formed. A step of applying over the entire mounting surface; a step of curing the sealing resin; and a step of dividing the base substrate along the division grooves formed on the base substrate. Semiconductor device manufacturing method. 2. A bare chip of a semiconductor integrated circuit is mounted in each unit section, and a thermosetting sealing resin is provided on a base substrate for a package in which a division groove for unit division is formed. Applying over the entire mounting surface, semi-curing the sealing resin, and pressing a jig against the sealing resin surface at a position corresponding to the dividing groove formed on the base substrate. A method of forming an auxiliary division groove by the method, a step of curing the sealing resin, and a step of dividing the base substrate along the division groove. 3. The method according to claim 2, wherein the jig is heated. 4. The method according to claim 2, wherein a depth of the auxiliary dividing groove formed on the surface of the sealing resin is set to be substantially equal to a thickness dimension of the applied sealing resin. 4. The method for manufacturing a semiconductor device according to item 3. 5. The shape of the auxiliary dividing groove formed on the surface of the sealing resin is such that the dividing end of the sealing resin for each unit section has a curved shape. A method for manufacturing a semiconductor device according to claim 2.