JP2000100821A - Semiconductor device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve productivity and to reduce the cost of a package material by providing a chip where a plurality of electronic parts are formed on one plane and a plurality of solder balls which connect the respective electronic parts to the outer part of a device, and forming a wiring part connecting the respective electronic components and the respective solder balls with conduction paste. SOLUTION: Innumerable electronic components are formed on one plane 2a of the chip 2 of a semiconductor device 10, and a plurality of pads 21 connecting the respective electronic components with a wiring part 4 are formed. Metal bumps 22 constituted of ball bonding formed of gold and solder are installed on one face 2a of the respective pads. The wiring part 4 is formed of the wirings 41 of conduction paste, which are patterned by screen printing on one plane 2a of the chip 2, and it is extended from the center of the chip 2 to the vicinity of an end part and is connected to the pads 21 via the metal bump 22. Since the wiring part 4 is formed of conduction paste, the cost of a package material can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device and a method of manufacturing a semiconductor device, and more particularly to a ball grid array type semiconductor device and a method of manufacturing a semiconductor device.

[0002]

2. Description of the Related Art Conventionally, semiconductor devices 50 and 60 which are chip scale packages of a ball grid array type having a plurality of solder balls for connecting internal electronic components to the outside of the device are shown in FIGS. 23 and 24, respectively. Show. As shown in the figure, in the semiconductor device 50, the lead frame 5
3 and a solder ball 54 on a lead frame 53. The lead frame 53 is connected by wire bonding to a pad 56 communicating with each electronic component on the chip 51. Except for the solder balls 54, the whole is sealed with a sealing resin 55.

A semiconductor device 60 has a lead frame 63 mounted on a chip 61 via an elastomer (adhesive body) 62, and a load beam 63 a extending from the lead frame 63 is provided on the chip 61. Connected to the pad 64. A solder ball 65 is provided on the lead frame 63, and a region other than the solder ball 65 is covered with a polyimide base material 66. The load beam 63a is sealed by a sealing resin 67.

[0004]

However, in each of the above semiconductor devices 50 and 60 and other conventional semiconductor devices, a wiring board such as a printed board, an adhesive tape, and a lead frame is relayed, and a load beam and a wire are further connected therefrom. The connection between the pad and the solder ball has been performed using bonding or the like.

For this reason, as a constituent material of a package of a semiconductor device, a wiring board such as a lead frame and a bonding means thereof and a connecting means such as a bonding wire and a load beam are indispensable, and these are costs of the package material of the semiconductor device. There has been an inconvenience that it becomes a major obstacle to reduction.

Further, the chip must be designed according to the existing lead frame, which limits the degree of freedom in designing and hinders the miniaturization of the chip.

Further, in a conventional semiconductor device, a sealing resin having a black color or a color similar thereto is used.
If the sealing resin is applied before cutting out the chips from the wafer, it is difficult to confirm the cutting position. Therefore, the chips must be individually resin-sealed after the cutting, which has a disadvantage of low productivity.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a semiconductor device and a method of manufacturing a semiconductor device which can solve the disadvantages of the conventional example, is suitable for reducing the cost of package materials, and has high productivity. .

[0009]

According to the present invention, there are provided a chip having a plurality of electronic components formed on one plane, a plurality of solder balls for connecting each electronic component to the outside of the device, each electronic component and each solder. And a wiring portion for connecting to a ball, and the wiring portion is formed of a conductive paste. In this case, it is desirable to form the conductive paste on one plane of the chip, particularly by screen printing.

In such a configuration, the conductive paste connects the electronic component and the solder ball instead of the lead frame.

Further, in addition to the above configuration, a plurality of pads for connecting each electronic component to the wiring portion are formed on one plane of the chip, and a convex metal bump is provided on each pad, and the wiring is formed from above. It is good also as composition which forms a part. Here, the pad indicates a so-called electrode. A large contact area with the wiring portion is secured by the metal bump, and the wiring portion is firmly fixed on the chip.

In particular, when the shape of the metal bump in the vicinity of the contact surface with the pad is set to a shape in which the cross-sectional area increases as the distance from the contact surface increases, the conductive paste enters the gap between the metal bump and the pad, Fix the wiring part firmly.

Further, each of the above-mentioned solder balls may be provided on the wiring portion via a thin metal plate.

Further, the above-mentioned wiring portion and each solder ball may be entirely formed on one plane of the chip, and one plane of the chip excluding each solder ball may be covered with a sealing resin. In this case, it is desirable that the sealing resin is transparent. In particular, if the sealing resin is transparent, the chip is cut out from the wafer by observing the wiring portion on one plane on the chip after the sealing, so that it is not necessary to individually perform resin sealing after the cutting. .

Further, regarding a method of manufacturing a semiconductor device,
A printing mask on which a wiring pattern is engraved on a wafer on which the electronic components of each chip and a plurality of pads for wiring connection of each electronic component are formed on one plane of the material of the plurality of chips. Position and mount, screen printing conductive paste on the wafer through the mask,
After the mask is removed, a plurality of solder balls for connecting each electronic component to the outside of the device are provided on the conductive paste, and each chip is divided from the wafer.

At this time, before mounting the mask, a convex metal bump may be provided on each pad, and a step of printing a conductive paste from above each metal bump may be added. Before mounting the solder balls, a thin metal plate may be mounted on the conductive paste at a position where each solder ball is to be mounted.

Further, after each solder ball is mounted and before each chip is cut, a sealing resin for sealing the conductive paste except for each solder ball may be applied to one surface of the chip. At this time, the sealing resin is desirably transparent.

The present invention is intended to achieve the above-mentioned object by each of the above-mentioned constitutions.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. FIG. 1A is a front view showing a cross section of a part of the semiconductor device 10 according to the present embodiment.

The semiconductor device 10 is a ball grid array type chip scale package, and has a flat surface 2a.
Chip 2 on which a plurality of electronic components (not shown) are formed
And a plurality of solder balls 3 for connecting each electronic component to the outside of the device, a wiring portion 4 for connecting each electronic component and each solder ball 3, and a plane 2a on which the electronic components of the chip 2 are formed. And a sealing resin 5 for coating.

Hereinafter, each part will be described in detail.

First, the chip 2 is cut out from a silicon wafer 20, which will be described later, and has a flat surface 2a.
An infinite number of electronic components (semiconductor elements) are formed thereon. Further, a plurality of pads 21 for connecting these electronic components to the wiring section 4 are formed on one plane 2a of the chip 2. The plurality of pads 21 are provided in a line in a row passing substantially through the center of the chip 2.

FIG. 1B is an enlarged explanatory view of a portion around the pad 21. As shown in this figure, a convex metal bump 22 is provided on one plane 2 a of each pad 21. The metal bump 22 is made of gold, solder, or the like, and the wiring portion 4 is formed on the metal bump 22 so as to surround the metal bump 22. This metal bump 22
It is preferable to use a bump formed by ball bonding and having a shape crushed by a ball, rather than a cylindrical bump formed by punching a metal ribbon.

By adopting such a shape, the shape of the vicinity of the contact surface 22a of the metal bump 22 with the pad 21 (the lower part of the metal bump 22) becomes larger as the distance from the contact surface 22a increases. The shape becomes larger. Therefore, when the conductive paste forming the wiring portion 4 is applied, the conductive paste 4 is applied to the region B between the surface around the contact surface 22a of the metal bump 22 and the upper surface of the pad.
Invades. Therefore, after the conductive paste is solidified, the metal bumps 22 are connected to the conductive paste 4 and the pads 21.
The conductive paste 4 is firmly fixed to the upper surface of the pad 21 so as to function as a wedge for joining the conductive paste 4 and the conductive paste 4. Further, since the metal bumps 22 are provided, a large contact area between the metal bumps 22 and the conductive paste 4 is ensured, so that the conductive paste 4 is firmly held.

Next, the wiring section 4 will be described. The wiring portion 4 is formed from a conductive paste wiring 41 patterned on the one plane 2a of the chip 2 by screen printing. As the conductive paste, for example, a silver paste is used. The wiring 41 of each conductive paste is
On one plane 2a of the chip 2, the chip 2 extends from the center to the vicinity of the end. One end of each wiring 41 of the conductive paste is connected to the pad 21 via the metal bump 22 as described above. The other end of each wiring 41 is provided with a land 42 which is a disk-shaped thin metal plate. For the land 42, a 42 alloy (Ni-iron alloy having a Ni content of 42%) or a Cu alloy is used.

On each of these lands 42, solder balls 3 are brazed. The solder ball 3 is a substantially spherical body made of solder. As described above, the myriad of semiconductor elements formed on the chip 2 are connected to the solder balls 3 via the pads 21, the metal bumps 22, the conductive paste wirings 41 and the lands 42 so as to be able to conduct electricity.

Then, a sealing resin 5 is applied on the semiconductor element forming surface of the chip 2 while covering the wiring portion 4. As shown in FIG. 1A, the sealing resin 5 covers only the base of each solder ball 3 and exposes the upper end side. In addition, a transparent resin is used for the sealing resin 5.

Next, a method of manufacturing the above-described semiconductor device 10 will be described with reference to FIGS. FIG. 2 is a flowchart showing the steps of the method of manufacturing the semiconductor device 10 in order, and FIGS. 3 to 11 are explanatory diagrams of each step.
Hereinafter, description will be made in order.

FIG. 3A shows a silicon wafer 20 used as a material of the chip 2. A plurality of chips 2 are finally formed by dividing the wafer 20 into squares. Further, as shown in FIG. 3 (B), the wafer 20 has innumerable semiconductor elements (not shown) of all the chips 2 and a plurality of pads for connecting the semiconductor elements to the wiring section 4 on one plane. 21 are formed.

A metal bump 22 is formed on the pad 21 of each chip 2 in the state of the wafer 20 by using a bump bonder (step S1, FIG. 4).

Next, the wafer 20 on which the metal bumps 22 are formed is covered with a metal mask on which a wiring pattern is decorated and positioned (step S2). After the positioning of the mask, a conductive paste such as a silver paste is screen-printed to form a wiring 41 made of the conductive paste on one plane 2a of the chip 2 (step S3, FIG. 5A). At this time, the metal bumps 22 are surrounded by the conductive paste (FIG. 5B). Next, 42 alloy or C is added to the ball mounting position on the wiring 41 formed of the conductive paste.
A land (a thin metal plate) 42 made of a u alloy is installed (step S4, FIG. 6A). It is desirable that the solder ball mounting surface of the land 42 be preliminarily subjected to the solder plating 42a (FIG. 6B).

Next, the solder ball 3 having a very small amount of the flux 3a applied to the lower portion is mounted (installed) on the land 42 (step S5, FIG. 7).

Next, in this state, the entire wafer 20 is subjected to reflow by infrared heating. By performing this reflow, the conductive paste 41 is hardened, and the metal bumps 22, the surface of the chip 2, and the lands 42 are bonded (Step S6). On the other hand, the solder ball 3 is heated and melted and brazed to the land 42 (FIG. 8).

Next, the transparent liquid sealing resin 11 is dropped on the wafer 20 to seal the surface of the wafer 20 with resin (step S7, FIG. 9). Then, the entire wafer 20 is baked in a baking furnace to cure the liquid sealing resin 11 (Step S8). The sealing resin 11 is not limited to the type that is cured by heating, but may be a type that is cured by UV irradiation or the like.

Next, after the resin-cured wafer 20 is affixed to a UV sheet or the like, the wafer 20 is cut into a chip size by a dicer along a dotted line in FIG. 10 to be separated as respective semiconductor devices 10 (step S9). ). FIG.
11A shows a completed semiconductor device 10, FIG. 11A is a front view of the semiconductor device 10, and FIG.
11 (C) shows a bottom view. Thus, a desired package of the semiconductor device 10 is completed.

In this embodiment having the above configuration, the wiring section 4 for connecting the semiconductor element on the chip 2 and the solder ball 3 is formed.
Is formed by a conductive paste, so that wiring boards such as printed circuit boards, adhesive tapes, and lead frames, which are conventionally required, and bonding means thereof and connection means such as bonding wires and load beams can be eliminated. In addition, it is possible to reduce the cost of the package material of the semiconductor device 10.

Further, since a lead frame or a wiring board and a tape for bonding the lead frame or the wiring board are not required, the thickness of the entire semiconductor device 10 can be made extremely thin. at the same time,
It is not necessary to match the size of the semiconductor device 10 with the existing lead frame, and the size of the semiconductor device can be reduced.

In particular, since the wiring portion 4 is in a paste form, it can be easily formed into a desired shape by screen printing. Therefore, it is not necessary to design a pad position according to an existing lead frame or the like, and the degree of design freedom is increased. , The productivity can be improved.

Further, since the wiring section 4 is formed on one plane 2a of the chip 2 on which the semiconductor element is provided and these are sealed with resin, the resin sealing is performed on the one plane 2a in the state of the wafer 20. It is sufficient to cut the individual chips 2 after the operation, and it is not necessary to individually perform resin sealing after cutting the chips 2 from the wafer 20 as in the related art, so that it is possible to improve productivity. .

At this time, by making the sealing resin 11 transparent, the cutting position can be easily confirmed when each chip 2 is cut from the wafer 20, and the productivity can be further improved. In addition to this, the cutting can be performed accurately, so that the processing accuracy can be improved.

Next, a semiconductor device 10A according to a second embodiment of the present invention will be described with reference to FIGS. Note that the same components as those of the semiconductor device 10 described above are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 12 is a partially cutaway front view of the semiconductor device 10A. This semiconductor device 10A has a configuration in which the metal bumps 22 on the pads 21 and the lands 42 are omitted from the configuration as compared with the above-described semiconductor device 10, thereby further simplifying the configuration.

That is, a conductive paste such as a silver paste is printed on a plurality of pads 21 provided on the chip 2 and on one surface 2a of the chip 2 by screen printing according to a predetermined wiring pattern, so that the wiring portion is formed. 4 are formed. The solder ball 3 is adhered to the one plane 2a of the chip 2 via the conductive paste wiring 41.

At this time, the pad 21 and the conductive paste,
Since the solder ball 3 and the conductive paste have a structure in which they are joined only by the adhesive force of the conductive paste, the characteristics of the conductive paste used in this embodiment include the conductive paste used in the semiconductor device 10. Rather, it is required that the adhesiveness to metal be strong.

The surface of the chip 2, the wiring 41 formed of the conductive paste, and the root of the solder ball 3 are:
The semiconductor device is covered with a transparent sealing resin 11 in the same manner as the semiconductor device 10.

Next, a method of manufacturing the semiconductor device 10A according to the present invention will be described with reference to FIGS. FIG. 13 is a flowchart showing a method of manufacturing the semiconductor device 12, and FIGS. 14 to 20 are explanatory diagrams of each step. Hereinafter, description will be made in order.

First, dicing (division for each chip 2)
A previous wafer 20 is prepared (FIG. 14A). The wafer 20 has the pads 21 for connection to the wiring portion 4 of the semiconductor element as described above.
(B)). The wafer 20 is covered with a metal mask on which a wiring pattern is decorated and positioned (Step S).
2).

After the positioning of the mask, a conductive paste such as a silver paste is screen-printed, and the wiring portion 4 is formed on the chip 2.
Is formed (step S3, FIG. 15). Next, the solder ball 3 is set at the ball mounting position on the wiring 41 formed of the conductive paste (step S5, FIG. 16),
In this state, reflow is performed for the entire wafer 20 (step S6). By performing such reflow, the conductive paste is hardened and adheres to the pads 21, the surface of the chip 2, and the solder balls 3 (FIG. 17).

Next, a transparent liquid sealing resin 11 is dropped on the wafer 20 to seal the surface of the wafer with the resin. The entire wafer is baked in a bake oven to cure the sealing resin (step S8, FIG. 18). The sealing resin 11 may be of a type that is cured by heating, or a type that is cured by UV irradiation or the like.

Next, after the resin-cured wafer 20 is affixed to a UV sheet or the like, the wafer is cut into a chip size along a dotted line in FIG. 19 by a dicer, thereby separating each of the semiconductor devices 10A (step S9). ). FIG.
Shows a completed semiconductor device 10A, FIG. 20 (A) is a front view of the semiconductor device 10A, FIG. 20 (B) is a right side view of the semiconductor device 10A, and FIG. 20 (C) is a bottom view. Thus, the package of the desired semiconductor device 10A is completed.

The semiconductor device 10A having such a configuration is as follows.
Since the configuration is simplified, the adhesive force between the solder ball 3 and the wiring 41 and the adhesive force between the wiring 41 and the chip 2 need to be compensated for by changing the material of the conductive paste. It has almost the same effect as the semiconductor device 10. Also, the metal bump 22 and the land 4
In order to reduce the material cost of No. 2 and reduce the number of manufacturing steps, it is possible to further improve productivity.

21 and 22 are partially cutaway sectional views of the semiconductor devices 10B and 10C based on the same concept as the semiconductor device 10A. The semiconductor device 10B
An example in which the metal bumps 22 are omitted from the configuration as compared with the semiconductor device 10 is shown.
In this example, the land 42 is omitted from the configuration in comparison with the example.

Since these semiconductor devices 10B and 10C have simplified structures, the adhesive force between the wiring 41 and the chip 2 or the adhesive force between the solder ball 3 and the wiring 41 is compensated for by changing the material of the conductive paste. Other than that, it has almost the same effect as the semiconductor device 10 described above. Also, the metal bump 22 or the land 42
In order to reduce material costs and reduce the number of manufacturing processes,
It is possible to further improve productivity.

[0054]

According to the present invention, the wiring portions for connecting the electronic components on the chip and the solder balls are formed by a conductive paste, so that conventionally required printed circuit boards, adhesive tapes, lead frames and the like are not required. It is possible to eliminate the need for the wiring board and the bonding means thereof and the connecting means such as the bonding wire and the load beam, so that the cost of the package material of the semiconductor device can be reduced.

Further, since a lead frame or a wiring board and a tape for bonding the lead frame or the wiring board are not required, the thickness of the entire semiconductor device can be made extremely thin. At the same time, it is not necessary to adjust the size of the semiconductor device to an existing lead frame, and the size of the semiconductor device can be reduced.

In particular, since the wiring portion is in a paste form, it can be easily formed into a desired shape by screen printing. Therefore, it is not necessary to design a pad position according to an existing lead frame or the like, and the degree of freedom in design is increased. Because it spreads, it is possible to improve productivity.

Further, by providing a wiring portion made of a conductive paste from above the metal bump on the pad, a large contact area between the conductive paste and the metal bump can be secured, and the wiring portion can be formed on the pad. Can be fixed firmly.

In particular, by forming the shape near the contact surface of the metal bump such that the cross-sectional area increases as the distance from the contact surface increases, the space where the conductive paste enters between the periphery of the contact surface and the pad is reduced. As a result, when the metal bumps are solidified, the metal bumps function as wedges, and the wiring portion can be more firmly fixed on the pads.

Further, since a wiring portion is formed on one plane of a chip provided with electronic components and these are sealed with a resin, after the resin is sealed on the one plane in a wafer state, individual parts are formed. You only have to cut it into chips.
Since it is not necessary to individually perform resin sealing after cutting the chips from the wafer, it is possible to improve productivity.

Further, by performing resin sealing after mounting the solder balls, the base portion of the solder balls and the space between the chips are filled with the resin, so that the joints of the solder balls are reinforced and the reliability after mounting the substrate is high. Become.

Further, at this time, by making the sealing resin transparent, when cutting each chip from the wafer, the cutting position can be easily confirmed, and the productivity can be further improved. Since the cutting can be performed accurately, the processing accuracy can be improved.

Since the present invention is constructed and functions as described above, according to the present invention, it is possible to provide an unprecedented excellent semiconductor device and its manufacturing method.

[Brief description of the drawings]

FIG. 1A is a partially cutaway front view of a semiconductor device according to a first embodiment of the present invention, and FIG. 1B is a partially enlarged view thereof.

FIG. 2 is a flowchart illustrating a method for manufacturing a semiconductor device.

FIG. 3 (A) is a perspective view showing a wafer of chip material, and FIG. 3 (B) is an enlarged perspective view showing one chip on the wafer.

FIG. 4A is a perspective view showing a state where metal bumps are provided on each pad of a chip, and FIG. 4B is a cross-sectional view of a part of the pad viewed from the side.

5 (A) is a perspective view showing a state where a wiring portion is formed from the state of FIG. 4 (A), and FIG. 5 (B) is a cross-sectional view of a part thereof as viewed from the side.

6 (A) is a perspective view showing a state where a thin metal plate is installed from the state of FIG. 5 (A), and FIG. 6 (B) is a side view of a part thereof.

7 (A) is a perspective view showing a state where solder balls are installed from the state of FIG. 6 (A), and FIG. 7 (B) is a side view of a part thereof.

FIG. 8 is a partially cutaway side view showing a state where the wafer has been reflowed from the state shown in FIG. 7A.

9A is a perspective view of a wafer in which a sealing resin is dropped from the state of FIG. 8, and FIG. 9B is an enlarged perspective view of one chip on the wafer at that time. It is a figure and FIG.9 (C) is the side view with which one part was notched partially.

FIG. 10 is a perspective view showing a cutting position of a wafer after resin sealing.

FIG. 11A is a front view of a divided semiconductor device, FIG. 11B is a right side view thereof, and FIG.
(C) is a bottom view thereof.

FIG. 12 is a partially cutaway front view of a semiconductor device according to a second embodiment of the present invention.

FIG. 13 is a flowchart illustrating a method for manufacturing a semiconductor device.

FIG. 14A is a perspective view showing a wafer made of a chip material, and FIG. 14B is an enlarged perspective view showing one chip on the wafer.

FIG. 15 is a perspective view showing a state where a wiring portion is formed from the state of FIG. 14 (B).

FIG. 16 is a perspective view showing a state where solder balls are installed from the state of FIG.

FIG. 17 is a partially cutaway side view showing a state where the wafer has been reflowed from the state shown in FIG. 16;

18A is a perspective view of a wafer in which a sealing resin is dropped from the state of FIG. 17, and FIG. 18B is an enlarged perspective view of one chip on the wafer at that time. FIG.

FIG. 19 is a perspective view showing a cutting position of a wafer after resin sealing.

FIG. 20A is a front view of a divided semiconductor device, FIG. 20B is a right side view thereof, and FIG.
(C) is a bottom view thereof.

FIG. 21 is a partially cutaway front view of a semiconductor device according to another example of the present invention.

FIG. 22 is a partially cutaway front view of a semiconductor device according to still another example of the present invention.

FIG. 23 is a partially cutaway front view of a conventional semiconductor device.

FIG. 24 is a partially cutaway front view of another conventional semiconductor device.

[Explanation of symbols]

 Reference Signs List 2 chip 2a one plane 21 pad 22 metal bump 22a bonding surface 3 solder ball 4 wiring part 41 wiring 42 land (metal thin plate) 10, 10A, 10B, 10C semiconductor device

Claims (12)

[Claims] 1. A chip having a plurality of electronic components formed on one plane, a plurality of solder balls for connecting each of the electronic components to the outside of the device, and connecting each of the electronic components to each of the solder balls. And a wiring portion, wherein the wiring portion is formed of a conductive paste. 2. The semiconductor device according to claim 1, wherein said conductive paste is formed on one plane of said chip by screen printing. 3. A plurality of pads for connecting each of the electronic components to the wiring portion are formed on one plane of the chip, a convex metal bump is provided on each pad, and the wiring portion is formed from above. 3. The semiconductor device according to claim 1, wherein the semiconductor device is formed. 4. The metal bump according to claim 3, wherein a shape of the metal bump in the vicinity of the contact surface with the pad is set to a shape in which a cross-sectional area increases as the distance from the contact surface increases.
13. The semiconductor device according to claim 1. 5. The semiconductor device according to claim 1, wherein each of the solder balls is provided on the wiring portion via a metal thin plate.
5. The semiconductor device according to 2, 3, or 4. 6. The semiconductor device according to claim 6, wherein the wiring portion and each of the solder balls are all formed on one plane of the chip, and the one plane of the chip except for the solder balls is covered with a sealing resin. Claims 1, 2,
6. The semiconductor device according to 3, 4, or 5. 7. The semiconductor device according to claim 6, wherein said sealing resin is transparent. 8. A wiring pattern is formed on a wafer which is a material of a plurality of chips, and on one surface of which a plurality of electronic components of the respective chips and a plurality of pads for wiring connection of the respective electronic components are formed. The printed mask is positioned and mounted, and a conductive paste is screen-printed on one plane of the wafer via the mask. After the mask is removed, the electronic components are placed on the conductive paste. A method of manufacturing a semiconductor device, comprising: a plurality of solder balls connected to the outside of a device; and each of the chips is divided from the wafer. 9. The method according to claim 8, wherein before mounting the mask, a convex metal bump is provided on each of the pads, and the conductive paste is printed from above each of the metal bumps. A method for manufacturing a semiconductor device. 10. The semiconductor device according to claim 8, wherein, before mounting the solder balls, a thin metal plate is mounted at a position where the solder balls are to be mounted on the conductive paste. Manufacturing method. 11. After the mounting of each of the solder balls and before cutting of each of the chips, a sealing resin for sealing the conductive paste is applied on one surface of the chip except for each of the solder balls. 11. The method for manufacturing a semiconductor device according to claim 8, 9, or 10. 12. The method according to claim 11, wherein the sealing resin is transparent.