JP2990130B2 - Manufacturing method of molded BGA type semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a BGA type semiconductor device.
It relates to a method of manufacturing, in particular, the mold BGA type semiconductor device
And a method for producing the same.

[0002]

2. Description of the Related Art A conventional BGA (Ball grid array) type semiconductor device is, for example, as shown in FIG. A polyimide tape 13 to which the copper wiring 11 is bonded is attached, the copper wiring 11 is bonded to the pad 2 of the semiconductor chip by thermocompression bonding, and the structure is sealed with a sealing material 12. Here, the example in which the pad 2 is provided in the peripheral portion of the semiconductor chip is shown, but there is also a case where the pad 2 is provided in the central portion.

[0003]

The conventional BGA type semiconductor device requires a polyimide tape to which an elastomer or copper wiring is bonded, and requires many parts and is expensive.

Since various polyimide tapes must be prepared according to the dimensions of the semiconductor chip and the arrangement of the pads, production management becomes complicated.

[0005] The pad and the copper wiring are joined by thermocompression bonding.
There are difficulties in achieving joint strength and uniformity, and there is a grudge that it is not easy to ensure reliability.

SUMMARY OF THE INVENTION An object of the present invention is to provide a molded BGA type semiconductor device which can more easily secure reliability with a smaller number of parts and a method of manufacturing the same.

[0007]

[0008]

Means for Solving the Problems] mold BGA of the present invention
The method of manufacturing a semiconductor device includes a set jig provided with a recess for mounting a semiconductor chip, and a set jig provided on a surface of the set jig where the recess is provided at a first predetermined distance from the recess. Preparing a work to be mounted, mounting and fixing a semiconductor chip in the recess, connecting a pad of the semiconductor chip and the work with a thin metal wire by wire bonding, and filling the recess with a mold resin. Forming a recess exposing the tip of the fine metal wire by selectively removing the mold resin and cutting the thin metal wire outside the mold resin; Forming an external terminal connected to the thin wire. In this case, the work is at a first height and a second height larger than the surface where the recess of the set jig is provided, respectively, and is at a first predetermined dimension and larger than the recess from the recess. It may have a first plane and a second plane separated by a second predetermined dimension.
Also, solder balls can be formed as external terminals by a reflow method.

Since the thin metal wires are directly connected to the external terminals, no elastomer or polyimide tape is required.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Manufacturing according to one embodiment of the present invention.
The molded BGA type semiconductor device is shown in FIG.
As shown in (b), a semiconductor chip 1 having pads 2 on its surface is sealed with a mold resin 8 and a mold B in which ball-shaped external terminals are arranged in an array on the surface of the mold resin 8.
In the GA type semiconductor device, the above-mentioned external terminals (solder balls 10) are provided directly on the pad 2 and the thin metal wires 3 on the surface of the mold resin 8 above the pads 2.

Next, a manufacturing method according to this embodiment will be described.

As shown in FIGS. 2A and 2B, a recess 51 occupying a rectangular area in a plane and having a width reduced in the depth direction.
Is prepared. The depth of the recess 51 is larger than the thickness of the semiconductor chip 1, the bottom is flat, and the bottom has the vacuum suction hole 7 and the eject pin insertion hole 61. The work 4 is set at a distance a from the recess 51. For example, a stainless steel work 4 has a flat surface 4 having a height b and a width c.
1 and a plane 42 of height d.

The semiconductor chip 1 is placed on the recess 51 of the set jig 5 with the surface on which the pads 2 are provided facing upward, and the vacuum suction hole 7 is connected to an exhaust pipe (not shown) to be vacuum-suctioned and fixed. I do. The planar shape of the semiconductor chip 1 is rectangular, and the pads 2r1, 2r2,
,..., 2l1, l2,... Are provided, and pads 2c1, 2c are also provided on an intermediate line passing through the center between the left and right long sides
2,... Are provided. It is assumed that coordinate points are regularly arranged on a plane 52 (indicated by a broken line) occupied by the aforementioned rectangular area. It is assumed that a solder ball is provided at this coordinate point and in the vicinity thereof. The distribution of the coordinate points corresponds to, for example, the position distribution of the solder balls defined by a standard by an external organization. The position distribution of the pads is not always constant depending on the type of the semiconductor device.

The pad and the work are connected by a thin metal wire, for example, a gold wire by a wire bonding method. The trajectory of the bonding head is numerically controlled so that the intersection (indicated by a black circle) of one thin metal wire and the plane 52 passes through the one coordinate point. According to the current numerical control bonding apparatus, the shape of the thin metal wire after bonding can be controlled in the X, Y, and Z directions with an accuracy of about ± 50 μm in consideration of the plastic deformation of the thin metal wire. The deviation between the intersection indicated by the black circle and the target coordinate point is about ± 50 μm or less.

Pads 2c1, 2c2 and 2c3 on the intermediate line
Are connected to the right plane 41, the left plane 41, and the right plane 41 of the work 4 by the thin metal wires 3c1, 3c2, 3c3,. The right pads 2r1,... Are connected to the left plane 42 by thin metal wires 3r1,.

Next, as shown in FIG. 3A, a liquid resin is dropped, solidified, and sealed with a mold resin 8.

Next, as shown in FIG. 3B, the thin metal wires 311 and 3r1 outside the mold resin 8 are cut and irradiated with an ultraviolet laser beam 9 to partially sublimate the mold resin 8. The dents 15 are formed by removing them. The irradiation position of the ultraviolet beam 8 is the above-described coordinate point and a circular area having a diameter of 300 to 400 μm around the coordinate point.

Next, as shown in FIG. 3C, a solder ball 10 is formed by a reflow method or the like. Since the size of the solder ball is 450 to 500 μm, it can be connected to the corresponding thin metal wire. Next, the semiconductor chip 1 is pushed up by the eject pin 6 and separated from the set jig 5 together with the mold resin.

The case where a work having four rows of solder balls and a level difference of 1 is used has been described above. When the number of rows is increased to 6,8, it is sufficient to use a work in which the step of the work is increased to 2,3.

[0020]

As described above, according to the present invention,
Since the pad and the external terminal are directly connected by a thin metal wire,
This eliminates the need for a polyimide tape or an elastomer to which copper wiring is bonded, reduces the number of components, and is advantageous for a CSP (chip size package). Even if the relative position between the external terminal and the pad changes due to the difference in thermal expansion between the mold resin and the semiconductor chip, there is no problem because the thin metal wire is flexible.
Since the connection between the pad and the thin metal wire is made by the wire bonding method, sufficient bonding strength and uniformity can be secured. Further, it can easily cope with various semiconductor chip dimensions. Since the structure of the set jig and the work is simple, the cost is low.

As described above, there is an effect that cost reduction and improvement in reliability of the molded BGA type semiconductor device can be easily realized.

[Brief description of the drawings]

FIG. 1 is a plan view (FIG. 1A) showing a molded BGA type semiconductor device manufactured according to an embodiment of the present invention, and a cross-sectional view taken along line XX of FIG. FIG. 1 (b).

FIG. 2 is a plan view (FIG. 2A) and a cross-sectional view (FIG. 2) for describing a manufacturing method according to an embodiment of the present invention.
(B)).

FIG. 3 is a process order sectional view shown in (a), (b), and (c) for explaining the manufacturing method of the embodiment of the present invention, following FIG. 2;

FIG. 4 is a cross-sectional view showing an example of the related art.

[Explanation of symbols]

1 semiconductor chip 2, 2c1, 2c2,...
.. 2r1, 2r2,..., Pad 3, 3c1, 3c2,.
· 3r1, 3r2, ··· Fine metal wire 4 Work 41 Flat surface 42 Flat surface 5 Set jig 51 Recess 52 Flat surface 6 Eject pin 61 Eject pin insertion hole 7 Vacuum suction hole 8 Mold resin 9 Ultraviolet laser beam 10 Solder ball 11 Copper Wiring 12 Sealant 13 Polyimide tape 14 Elastomer 15 Depression

Claims (3)

(57) [Claims] The method according to claim 1] workpiece recess setting jig and the setting jig having a recess for mounting the semiconductor chip is mounted from said recess in a surface which is provided apart first predetermined size Prepare, place and fix the semiconductor chip in the recess,
Connecting the pad of the semiconductor chip and the work with a thin metal wire by wire bonding, forming the mold resin by filling the recess, cutting the thin metal wire outside the mold resin, A step of forming a recess for exposing the tip of the thin metal wire by selectively removing the fine wire, and a step of forming an external terminal connected to the thin metal wire by filling the recess. Of manufacturing a semiconductor device. 2. The workpiece is at a first height and a second height greater than the surface of the set jig where the recess is provided, and the workpiece has a first predetermined dimension and a predetermined height from the recess. 2. The method of manufacturing a molded BGA type semiconductor device according to claim 1, further comprising a first plane and a second plane separated from each other by a larger second predetermined dimension. 3. The mold BG according to claim 1 , wherein a solder ball is formed by a reflow method as the external terminal.
A method for manufacturing an A-type semiconductor device.