JP2001015630A - Bga-semiconductor package and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To assure good flatness of the lowest plane of a package without being influenced by package materials and a manufacturing process by pushing a flat plate against solder balls to make substrate-mounting faces of the solder balls flat with respect to the substrate to be mounted. SOLUTION: A semiconductor package 15 is placed with solder-balls 11 side up on a first flat plate 16, which is a jig having a flat upper plane. A second flat plate 17 of glass, ceramic or metal is placed on the semiconductor package 15, and is pressed. By such means, substrate-mounting faces of the solder balls 11 are made flat with respect to a substrate to be mounted, and a BGA(ball grid array)-type semiconductor package having a flat lowest plane is obtained. As a result, good flatness of the lowest plane is assured without being influenced by package materials and manufacturing process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a BGA (Ball Grid Array) type semiconductor package on which solder balls are mounted,
In particular, the present invention relates to a BGA type semiconductor package in which the top of a solder ball is flat.

[0002]

2. Description of the Related Art At present, B is one of the semiconductor packages.
There is a GA (Ball Grid Array) package. this is,
A package in which solder balls are arranged in an area array mainly on the lower surface of the package in order to form ball bumps as connection leads between the mounting substrate and the package.
al Inline Package) and QFP (Quad Flat Package)
As compared with a package of the type in which lead terminals are arranged in the periphery as described above, there is an advantage that the package size can be reduced even with the same number of pins, and thus it has been widely adopted recently.

[0003] Solder balls as the external connection terminals are usually formed on the lower surface of the package by mounting spherical solder balls on the lower surface of the package and melting them by heating. Since the solder ball is formed on the package by heating and melting, as shown in FIG. 2A, the surface is usually spherical due to the surface tension of the solder.

On the other hand, as a BGA type semiconductor package which handles a solder ball having a flat top, there is, for example, one disclosed in Japanese Patent Application Laid-Open No. 10-4127. This is because, on a wiring board, an intaglio filled with solder paste is arranged so that the recess faces downward, and the solder paste is melted in a reflow furnace. Flatten the top of the solder ball all at once,
The height of the solder balls is made uniform. According to this,
There is an advantage that the coplanarity of the solder ball can be reduced, so that the bonding property between the wiring board and the flip chip or the printed board can be improved, and the continuity test and the insulation test can be reliably performed. .

[0005]

A solder ball as a terminal of a BGA type semiconductor package is usually spherical as described in the prior art.

[0006] On the other hand, EIAJ (Electronic Manufacturers Association of Japan) has published EGAJ
DR-7315 and EDR-7316 have been established.
Items relating to the ball in the design guide are mainly the ball diameter and the uniformity of the lowermost surface of the package. The ball diameter is determined by the diameter of the solder ball to be mounted, and the flatness of the lowermost surface of the package depends on the flatness of the package material itself and the variation of the ball diameter. According to the EIAJ standard, the flatness of the lowermost surface of the package is 0.1 mm when the terminal linear interval is 0.8 mm. The current tolerance of the solder ball diameter is ± 10 μm (Senju Metal Industry), and the difference (a difference of ± 10 μm) is 20 μm, and the tolerance of the solder ball alone already occupies 20% of the allowable tolerance.

Here, as a BGA type semiconductor package, TAB (Tape Automat) which is a flexible wiring board is used.
ed Bonding) Tapes are attracting attention. FIG.
In the stiffener 9 made of a metal plate, a concave portion 23 for mounting a semiconductor chip is formed at the center of the lower surface of the stiffener 9 by integral bending, and a TAB base material 22 made of polyimide resin is formed on the lower surface of the stiffener 9 via an adhesive 24. Wiring pattern 21
TAB tape 20 including package (package base material 14)
And a semiconductor chip 40 is fixed at the center of the bottom surface of the concave portion and sealed with a sealing resin 50. By attaching the stiffener 9 to the top surface of the package body, flatness on the solder ball surface of the package is ensured and heat dissipation is improved.

FIG. 11 shows a semiconductor device which is reduced in size by using a TAB tape with an elastomer for BGA. This was assembled as follows. First, the film elastomer 10 is attached to a TAB tape 20 having a TAB base material 22 and a wiring pattern 21 to form a TAB tape 30 with an elastomer for BGA (FIG. 11A). T with Elastomer for BGA
The semiconductor chip 40 is mounted on the AB tape 30 (FIG. 11B). The semiconductor chip 40 is connected to the TA via the elastomer 10 made of a film having adhesive properties on both sides.
It is adhered to the B tape 20. Next, the inner leads 21a of the obtained TAB tape 30 with elastomer for BGA are used.
Are formed in an S shape and connected to the electrodes of the semiconductor chip 40 (FIG. 11C). That is, the bonding tool cuts the notch of the lead, further forms the lead in an S-shape, and bonds the electrode on the electrode by heat and ultrasonic waves. Next, the electrodes of the bonded semiconductor chip 40 and the leads 21a are sealed with a sealing resin 50 (FIG. 11D). Then, the solder balls 11 are mounted on the lands of the TAB tape 20 (FIG. 11E), and laser marking or printing is performed on the chip surface (FIG. 11F). Finally, T with BGA elastomer
It is cut into pieces by punching out from AB tape 30, and B
The GA type semiconductor package 15 is used.

If a tape-type material such as the above-mentioned TAB tape is used for the package base material, the flatness of the material needs to be suppressed to within ± 40 μm. However, in the conventional technique of heating and melting the whole, the lowermost flatness of the BGA type semiconductor package is entirely determined by the finished dimensions at the time of product completion. In other words, B
The lowermost flatness of the GA type semiconductor package depends on the package material and the manufacturing process. Therefore, it is very difficult, if not impossible, to satisfy the above requirements with such passive technology, which is very difficult and problematic.

[0010] This point is a method in which the solder paste is filled into an intaglio plate and melted in a reflow furnace, that is, at the time of melting, the tops of a plurality of solder balls are collectively flattened using the bottom surface of the intaglio recess, and the height of the solder balls is reduced. The same problem also exists in the method of equalizing (Japanese Patent Laid-Open No. 10-4127). In addition, in the case of Japanese Patent Application Laid-Open No. H10-4127, it is necessary to temporarily place the intaglio mounted on the wiring board in a reflow furnace, and to heat the solder to the melting point of the solder or higher and then cool it down. It takes time to remove the intaglio afterwards.

Accordingly, an object of the present invention is to solve the above-mentioned problems, and to provide a BGA which can ensure excellent flatness at the lowermost surface without being influenced by a package material and a manufacturing process.
It is an object of the present invention to provide a semiconductor package and a method of manufacturing the same.

[0012]

In order to achieve the above object, a BGA type semiconductor package according to the present invention is configured as follows.

(1) According to the first aspect of the present invention, in a BGA type semiconductor package on which solder balls are mounted, a shape of a mounting portion of the mounting substrate of the solder balls is mounted by pressing a flat plate against the solder balls. It has a structure having a flat portion with respect to the substrate. The solder ball is a soft alloy, and when pressed against a flat plate, the lower surface is crushed and becomes a flat lower surface. Therefore, a flat surface having the same height and the same inclination is formed very simply and on the top of each solder ball, and required flatness of the lowermost surface of the package can be secured.

(2) The invention described in claim 2 is the first invention.
In the BGA type semiconductor package described above, the flat portion of the solder ball is formed by pressing a flat plate made of a glass plate, a ceramic plate, or a metal plate having flatness. The flatness of the flat plate made of a glass plate, a ceramic plate or a metal plate pressed against the solder balls is preferably, for example, within ± 2 μm. As a result, even in a semiconductor package using a TAB tape, the lower surface shape of the ball having good flatness can be collectively obtained for each solder ball, and the required lowermost surface flatness of the package can be provided.

(3) The invention described in claim 3 is the invention according to claim 1.
In the BGA type semiconductor package described above, the flat portion of the solder ball is formed by previously heating a flat plate made of a material that does not wet with solder to near the solder melting point and pressing the flat plate against the solder ball with a minimum necessary pressure. It is of a structure. Since the flat plate is pre-heated to near the solder melting point, the lower surface of the ball with good flatness can be easily formed collectively and easily by pressing the solder ball with the minimum necessary pressure, and the required lower surface flatness of the required package Can be provided.

(4) According to a fourth aspect of the present invention, in the BGA type semiconductor package according to the first, second or third aspect, the flat portion of the solder ball has an arbitrary in-plane shape such as a cross. It has a structure with the remaining shape. The in-plane shape of the flat portion of the solder ball has a shape such as a cross shape that leaves an arbitrary convex portion, so that the wettability to the solder paste on the mounting board is improved compared to a surface shape without such a convex portion. Can be improved.

(5) A method of manufacturing a BGA type semiconductor package according to claim 5, wherein one or a plurality of BGA type semiconductor packages on which solder balls are mounted are arranged such that the solder balls are on the upper side and are substantially the same. Use a jig so that they are flush with each other, and press a common flat plate against each solder ball of each of the BGA type semiconductor packages. To form a flat portion. Thereby, a flat portion is simultaneously formed for each solder ball of one or a plurality of BGA type semiconductor packages,
The required flatness of the lowermost surface of the package for each type semiconductor package can be ensured.

(6) A method of manufacturing a BGA type semiconductor package according to claim 6, wherein one or more BGA type semiconductor packages on which solder balls are mounted are mounted on a flat jig such that the solder ball side is on the upper side. On each of them B
By pressing a flat plate in common to each solder ball of the GA type semiconductor package, a flat portion with respect to the mounting board is formed at the mounting board mounting portion of the solder ball. Thereby, a flat portion is simultaneously formed on each solder ball of one or a plurality of BGA type semiconductor packages, and required flatness of the lowermost surface of the package for each BGA type semiconductor package can be secured. BGA having the structure of FIG. 10 in which a stiffener is attached to a TAB tape
Suitable for semiconductor package.

(7) The invention according to claim 7 is the invention according to claim 5
Or the method of manufacturing a BGA type semiconductor package according to 6, wherein a flat plate made of a material that does not wet with solder is used as the flat plate, and the flat plate is heated to near the solder melting point in advance,
By pressing the solder ball against the solder ball with a minimum necessary pressure, a flat portion is formed on the mounting board mounting portion of the solder ball. Since the flat plate is preheated to near the melting point of the solder, pressing the solder ball with the minimum necessary pressure makes it possible to very easily form a flat bottom surface with good flatness, and to use each BGA
The required flatness of the lowermost surface of the package for each type semiconductor package can be ensured. It is suitable for the BGA type semiconductor package having the structure shown in FIG. 5, FIG. 10, or FIG.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment.

The method for obtaining the BGA type semiconductor package of the present invention is roughly classified into two types, a pressurizing method and a heating method.

A. Pressurization method First, as shown in FIG. 1 (a), a BGA mounted with solder balls
The mold semiconductor package 15 is placed on a first flat plate (with a flatness within ± 2 μm) 16 which is a jig having a flat upper surface such that the solder balls 11 face upward. When the type shown in FIG. 10 is used as the BGA type semiconductor package 15, the stiffener 9 has the convex portion 9 a corresponding to the concave portion 23 for mounting the semiconductor chip. It is preferable to prepare a jig with a flat upper surface having a recess for depression of the convex portion 9a. However, a jig whose upper surface is simply flat may be prepared as the first flat plate 16.

When the BGA type semiconductor package 15 is merely mounted on the first flat plate 16, the shape of the solder ball 11 at this time is still spherical as a whole as shown in FIG. In FIG. 2A, reference numeral 12 denotes a solder resist resin provided around a land (copper foil) 13 serving as a solder ball mounting electrode, and is not shown in FIG.

Next, as shown in FIG.
The semiconductor package 15 is mounted on a second flat plate (flatness ±) made of a flat glass plate, ceramic plate or metal plate.
(Within 2 μm) using a pressure of 17 (up to 10 μm)
kg / cm ² ) (FIG. 1 (c)). As a result, the shape of the mounting portion of the solder ball 11 on the mounting substrate is changed to a flat portion 11 with respect to the mounting substrate (not shown) as shown in FIG.
a, and a BGA type semiconductor package with good flatness of the lowermost surface is obtained.

(2) Heating method First, a BGA type semiconductor package 15 on which solder balls are mounted is placed on a first flat plate (flatness ± 2 μm Within), the solder ball 11 is placed on 16 so as to face upward.

Next, a second flat plate 27 (within a flatness of ± 2 μm) made of a material which does not get wet with metal is heated to near the solder melting point in advance, and this heated second flat plate 27 is heated. Is pressed against the solder ball 11 with a minimum necessary pressure. As a result, the shape of the mounting board mounting portion of the solder ball 11 is made into a shape having a flat portion 11a with respect to the mounting board as shown in FIG. 2B, and a BGA type semiconductor package with good flatness on the lowermost surface is obtained. .

The above embodiment has been described on the assumption that the in-plane shape of the flat portion of the solder ball is uniformly flat. However, in order to improve the wettability to the solder paste on the mounting board, in the BGA type semiconductor package 15, the flat portions 11a of the solder balls 11 are formed.
Can have a shape in which an arbitrary convex portion such as a cross shape is left.

FIG. 3 shows a flat portion 11 of the solder ball 11.
This is an example in which the in-plane shape of a is formed so as to have a shape that leaves a rectangular convex portion 11b as viewed from the upper surface, and the ball tip shape is a cube. FIG. 4 shows the in-plane shape of the flat portion 11a of the solder ball 11 as viewed from the upper surface.
This is an example in which it is formed to have a shape leaving 1c.

Next, by using a jig, a plurality of BGA
A method for simultaneously handling the type semiconductor package will be described. That is, this is a method in which a plurality of semiconductor packages are set and processed at once instead of a single product.

FIG. 5 shows the structure of a target BGA type semiconductor package. This is a small CSP (Chip Scale)
Package), and a sheet-like flexible circuit board 7 cut out from the flexible tape 4 shown in FIG. 9 is pre-opened in the opening 2 provided four adjacent to the metal frame 1 shown in FIG. What is pasted with an adhesive 8 (FIG. 8) provided on the periphery is an intermediate product for a semiconductor package (FIG. 6). Then, by transporting the intermediate product for semiconductor package to each process, the existing QFP
The semiconductor device mounting, wire bonding, resin sealing, solder ball mounting, and other processes are performed using the manufacturing equipment for manufacturing the (Quad Flat Package) as it is.

The flexible circuit board 60 shown in FIG.
Is a single circuit board 6 (FIG. 6,
As shown in FIG. 9), four of them are continuously formed in a cross shape, and have a circuit pattern 21 made of copper foil on one side.

First, a sheet-like flexible circuit board 7 cut out from the flexible tape 4 of FIG. 9 is attached to the opening 2 of the metal frame 1 shown in FIG. 7 via an adhesive 8 (FIG. 8), A resist resin 12 is applied to the surface of the pattern to produce an intermediate product for a semiconductor package. Reference numeral 3 denotes a guide hole for positioning the metal frame 1 and reference numeral 5 denotes a guide hole for the flexible tape 4. Then, the semiconductor chip 40 is mounted on the conductive circuit board 6 of the semiconductor package intermediate product.

Next, the gap between the electrode 19 of the semiconductor chip 40 and the connection pad (gold plating 13b) of the circuit pattern is
Wire bonding is performed by the bonding wire 18.

Further, a sealing resin 50 or a potting material is applied on the semiconductor chip 40 and the bonding wires 18.

After resin sealing, solder balls 11 are attached to the lower surface of the circuit board 60 as external connection terminals to be connected to the mounting board. Note that a part of the circuit pattern is
0 is led out to one side on the other side through a via hole provided with gold plating 13a penetrating through the solder ball 1a.
1 is connected.

The BGA type semiconductor package 15 on which the solder balls 11 are mounted is a sheet-like flexible circuit board (collective circuit board) 7 cut out from the flexible tape 4 in the intermediate product for a semiconductor package (FIG. 6).
The unit is set using a jig such that the solder ball side 11 is on the upper side and substantially flush with each other.

Next, a second flat plate 27 (within a flatness of ± 2 μm) made of a material which does not get wet with metal and having a good flatness is heated to near the melting point of the solder in advance, and the heated second flat plate 27 is heated. Is pressed against the solder ball 11 with a minimum necessary pressure (FIGS. 1A to 1C). Thereby, the shape of the mounting board mounting portion of the solder ball 11 is made into a shape having a flat portion 11a with respect to the mounting board as shown in FIG. 5, and a BGA type semiconductor package with good flatness on the lowermost surface is obtained.

In the above embodiment, the flexible tape 4
The size of the sheet-like flexible circuit board (assembled circuit board) 7 cut out from the above is defined as a unit (pressing range) handled by one operation, and the flat portion 11a is collectively formed on the solder balls 11 included in the range. However, a unit (pressing range) in which the size of a plurality of sheet-like flexible circuit boards (assembled circuit boards) 7 which are gathered by a plurality of sheets, for example, the size of the intermediate product for a semiconductor package (FIG. 6) in one operation. Alternatively, a flat portion 11a may be collectively formed on the solder balls 11 included in the range.

Finally, by removing the flexible circuit board 7 from the metal frame 1 or the circuit board 60 from the flexible circuit board 7, a small grid area array type semiconductor package can be obtained as a single BGA product.

Normally, flexible tape for a small grid area array type semiconductor package as described above cannot be produced using an apparatus for manufacturing a lead frame package, and investment such as introduction of a new apparatus is required. Required. However, if the intermediate product for a semiconductor package according to the present embodiment is used, it is possible to manufacture a semiconductor package by using a device for a large lead frame package. That is, according to the method of manufacturing a semiconductor package according to the above-described embodiment, a conventional apparatus for manufacturing a QFP is called a FBGA (Fine Pitch Ball Grid Array).
The SP can be manufactured. In addition, the present invention has no limitation on the semiconductor element to which the present invention is applied, and is applicable to any of memories such as DRAM and SRAM, and logic systems such as CPU and MPU.

The above manufacturing method can also be applied to a plurality of BGA type semiconductor packages 15 of the type shown in FIGS. Type B of FIG.
When the present invention is applied to a package in which a plurality of GA type semiconductor packages 15 are arranged, the jig to be set is on a first flat plate (flatness within ± 2 μm) 16 which is a jig having a flat upper surface. The solder balls 11 may be placed so that the solder balls 11 face upward. Since the stiffener 9 has the convex portion 9a, the first flat plate 16 is preferably a jig having a flat upper surface having a concave portion for the convex portion 9a corresponding to the concave portion for mounting a semiconductor chip. prepare. This is because handling is easy in securing accuracy.

There is also a BGA type semiconductor package structure similar to that shown in FIG. 10, but a type in which the convex portion 9a is not formed on the surface of the stiffener 9 and has a flat surface. In the case where a plurality of BGA type semiconductor packages similar to those shown in FIG. 10 are continuously provided on the frame, the flat portion 11a can be easily formed as follows.

That is, in the case of the pressure method, (1) BGA type semiconductor packages 15 on which the solder balls 11 are mounted are prepared in a size corresponding to the number to be processed in one operation.

(2) These BGA type semiconductor packages 15 are placed on a first flat plate 16 such as glass, ceramic or metal having a surface flatness smaller than ± 2 μm.
Is placed so that the surface opposite to the surface on which the solder balls 11 are mounted is in contact.

(3) The flatness of the surface of another prepared glass, ceramic, metal or the like is ± 2 μm.
a second flat plate 17 smaller than m and a first flat plate 16 on which the semiconductor package 15 is placed from above the package.
Drop parallel to.

(4) The second flat plate 1 in which all surfaces of the solder balls 11 mounted on the semiconductor package 15 are lowered
The upper first flat plate 16 is lowered until it touches 7.

(5) The first flat plate 16 is lowered to a required position (an arbitrary position within the ball radius when the position where the upper flat plate is in contact with the ball is set to zero). At that time, the pressing pressure is set to 10 g / cm ² or less.

(6) Thus, a semiconductor package having a required shape is completed.

In the case of the heating method, (1) a BGA type semiconductor package 15 on which the solder balls 11 are mounted is prepared.

(2) It is placed on a first flat plate 16 such as glass, ceramic or metal having a surface flatness smaller than ± 2 μm so that the surface opposite to the ball mounting surface is in contact.

(3) The flatness of the surface of another prepared glass, ceramic, metal or the like is ± 2 μm.
The second flat plate 17 smaller than m is lowered from above the package in parallel to the first flat plate 16 on which the package is placed. At this time, the upper flat plate has a solder ball melting point of ± 5 ° C.
Has been adjusted.

(4) Lower the upper second flat plate 17 until all surfaces of the solder balls 11 mounted on the package touch the lowered second flat plate 17.

(5) Required position (upper second flat plate 1)
If the position where 7 contacts the ball is set to zero, the second flat plate 17 is lowered to an arbitrary position within the ball radius length). At that time, the pressing pressure is set to 10 g / cm ² or less.

(6) Thus, a semiconductor package having a required shape is completed.

By using either the pressurizing method or the heating method, the lowermost surface flatness is better than that of the conventional type, that is, the lowermost surface flatness ± 10 μm with respect to the current maximum tolerance ± 20 μm.
The BGA type semiconductor package within is surely formed.

When the top surface of the flat portion of the ball mounting portion has a shape having convex portions 11a and 11b of an arbitrary shape, the ball contact portion of the flat plate 17 on the side contacting the solder ball 11 is formed. A groove is formed in advance, and the flat plate 17
The protrusion 1 of an arbitrary shape is formed at the tip of the solder ball 11 by using
1a, 11b and the like are formed.

In the above embodiment, the semiconductor package is set so that the solder balls are on the upper side, and the second
However, the second flat plate 17 can be pressed against the solder balls with the semiconductor package being set upside down.

[0058]

The flatness of the lowermost surface of the conventional BGA type semiconductor package is determined by the finished dimensions when the product is completed. However, the BGA type semiconductor package of the present invention (Claims 1 to 4) or a manufacturing method thereof (Claim 5)
According to 7), the mounting board of the solder ball is pressed by pressing the flat plate against the solder ball, or by pressing the flat plate heated in advance to the vicinity of the solder melting point with the minimum necessary pressure. Since the mounting part is shaped to have a flat part with respect to the mounting board,
Even in a semiconductor package using a TAB tape, a flat surface having the same height and the same inclination can be formed on the top of each solder ball very easily. Therefore, it is possible to manufacture and supply a BGA type semiconductor package with good flatness on the bottom surface without being affected by the package material and the manufacturing process.

[Brief description of the drawings]

FIG. 1 is a view illustrating a pressing process for manufacturing a BGA type semiconductor package according to the present invention.

FIG. 2 shows the shape of a solder ball mounted on a BGA type semiconductor package of the present invention, wherein (a) is a cross-sectional view of the solder ball before pressing according to the present invention, and (b) is a solder ball after pressing. FIG.

3A and 3B show a modified example of a solder ball shape of a BGA type semiconductor package according to the present invention, wherein FIG. 3A is a longitudinal sectional view of a solder ball having a cubic shape at the ball tip;
(B) is a top view thereof.

4A and 4B show another modified example of the solder ball shape of the BGA type semiconductor package according to the present invention. FIG. 4A is a longitudinal sectional view of a solder ball having a ball tip having a cross shape.
(B) is a top view thereof.

FIG. 5 is a view illustrating a B manufactured by a method according to an embodiment of the present invention.
It is sectional drawing which shows an example of a GA type semiconductor package.

FIG. 6 is a plan view showing an intermediate product for a semiconductor package obtained during a manufacturing method according to an embodiment of the present invention.

FIG. 7 is a plan view showing a metal frame used in the manufacturing method according to one embodiment of the present invention.

FIG. 8 is a view showing an opening of a metal frame used in the manufacturing method according to the embodiment of the present invention.

FIG. 9 is a view showing a flexible tape used for producing a flexible circuit board used in the manufacturing method according to one embodiment of the present invention.

FIG. 10 is a cross-sectional view showing a BGA type semiconductor package having a structure in which a stiffener is bonded to a conventional TBA tape.

FIG. 11 shows a conventional B using a TAB tape with an elastomer.
It is a figure showing a manufacturing process of a GA type semiconductor package.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Solder ball 11a Flat part 12 Resist resin 13 Land 14 Package base material 15 BGA type semiconductor package 16 1st plane board 17 2nd plane board

Claims (7)

[Claims] In a BGA type semiconductor package on which a solder ball is mounted, a flat board is pressed against the solder ball, so that the mounting portion of the solder ball has a flat portion with respect to the mounting substrate. A BGA type semiconductor package characterized by the above-mentioned. 2. The BGA type semiconductor package according to claim 1, wherein the flat portion of the solder ball is formed by pressing a flat plate made of a glass plate, a ceramic plate or a metal plate having flatness. A BGA type semiconductor package characterized by the above-mentioned. 3. The BGA type semiconductor package according to claim 1, wherein a flat plate of the solder ball is heated in advance to a solder melting point near a flat plate made of a material that does not wet the solder.
A BGA type semiconductor package formed by pressing a solder ball with a minimum necessary pressure. 4. The BGA type semiconductor package according to claim 1, wherein the in-plane shape of the flat portion of the solder ball has a shape such as an arbitrary cross portion or the like. BGA type semiconductor package. 5. One or a plurality of Bs on which solder balls are mounted.
The GA type semiconductor package is set using a jig so that the solder ball side thereof is on the upper side and substantially flush with each other, and a flat plate is commonly used for each of the solder balls of each of the BGA type semiconductor packages. And forming a flat portion with respect to the mounting board on the mounting board mounting portion of the solder ball by pressing the solder ball. 6. One or a plurality of BGA-type semiconductor packages on which solder balls are mounted are placed on a flat jig such that the solder balls are on the upper side, and each of the solder balls of each of the BGA-type semiconductor packages is mounted. A method of manufacturing a BGA type semiconductor package, characterized in that a flat plate is formed on a mounting board mounting portion of a solder ball by pressing a common flat plate against the mounting board. 7. The method of manufacturing a BGA type semiconductor package according to claim 5, wherein a flat plate made of a material that does not wet with solder is used as the flat plate, and the flat plate is heated to near the melting point of solder beforehand. A method of manufacturing a BGA type semiconductor package, wherein a flat portion is formed on a mounting board mounting portion of a solder ball by pressing the solder ball against the solder ball with a minimum pressure.