JP2001135769A - Method of manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a semiconductor device, with which a semiconductor device having a compact appearance and a favorable mounting property can be manufactured, without having to increase manufacturing cost or accompanied by deterioration in the product quality. SOLUTION: This method of manufacturing a semiconductor device includes steps of mounting a semiconductor chip 4 on a lead frame 10, having a plurality of leads 11 via an insulating bonding material, connecting the semiconductor chip 4 and the leads 11 to each other via-bonding wires 5, resin-sealing the semiconductor chip 4, the bonding wires 5 and a sealed region 10P of the lead frame 10 by a package 2, forming an opening 12h corresponding to the leads 11 in a package 2 mounting surface (lower surface) by laser processing and providing solder balls (external connection terminals) 3, having continuity with the leads 11 via the opening 12h on the package 2 mounting surface (lower surface) 2a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method of manufacturing a semiconductor device, and more particularly to a method of manufacturing a BGA (ball grid array) type semiconductor device using a lead frame.

[0002]

2. Description of the Related Art A recent semiconductor device is required to have a smaller size and a larger number of pins as the density of the semiconductor device is increased on a printed circuit board. (Ball Grid Array) type semiconductor device is provided.

A BGA type semiconductor device A shown in FIG.
A semiconductor chip Ab is mounted on a wiring board Aa made of glass epoxy resin or the like on which a wiring pattern is formed, and the wiring pattern of the wiring board Aa is electrically connected to the semiconductor chip Ab. Ab is sealed with a mold resin Ac, and a solder ball Ad as an external connection terminal is provided on the wiring board Aa.

On the other hand, a BGA type semiconductor device B shown in FIG. 7 is a semiconductor device manufactured by using a lead frame, in which a semiconductor chip Bb is mounted on a pad Bp, and each lead Ba and the semiconductor chip Bb are mounted. Are connected by a bonding wire Bc, and they are sealed with a molding resin Bd.
(Package) A solder ball Be is provided on the lower surface of Bd as an external connection terminal that is electrically connected to each lead Ba.

[0005]

According to the conventional semiconductor device A shown in FIG. 6, although the appearance can be reduced as much as possible, the wiring board Aa is an essential component. However, there is a disadvantage that the cost is increased.

Further, in the above-described semiconductor device A, since the molding resin Ac protecting the semiconductor chip Ab is formed only on one surface (upper surface) of the wiring board Aa,
When the molding resin Ac is molded at a high temperature (for example, 160 to 200 ° C.), warping deformation occurs due to a difference in thermal expansion coefficient between the molding resin Ac and the wiring board Aa.

[0007] For this reason, when the level of the wiring board Aa is deteriorated, not only the mountability with respect to the printed circuit board is reduced, but also the wiring board Aa with insufficient adhesion.
And the mold resin Ac peeled off.

On the other hand, according to the conventional semiconductor device B shown in FIG. 7, the size can be reduced as much as possible, and the cost due to the use of the wiring board Aa (FIG. 6) increases. Can be prevented.

In the semiconductor device B, the molding resin Bd covers the top and bottom of each lead Ba and the semiconductor chip Bb, and the lead frame having good adhesion to the molding resin Bd is used. Warp deformation when the mold resin Bd is molded at a high temperature is suppressed, mountability on a printed circuit board is improved, and peeling of the mold resin Bd from the pads Bp and the leads Ba is prevented as much as possible.

On the other hand, when manufacturing the semiconductor device B, it is necessary to form a large number of openings Bh on the lower surface of the molding resin (package) Bd for conducting each solder ball Be with each lead Ba.

For this reason, in the lower mold of the resin sealing mold, it is necessary to form a large number of convex portions for molding the respective openings Bh, Bh. There has been an inconvenience that the cost increases and the manufacturing cost of the semiconductor device increases.

Further, since a large number of convex portions formed on the lower mold of the resin sealing mold hinder the smooth flow of the mold resin at the time of resin sealing, resin molding failure, that is, molding resin (package) ) Bd chipping is likely to occur,
There has been a disadvantage that the product quality as a semiconductor device is reduced.

An object of the present invention is to provide a semiconductor device capable of manufacturing a semiconductor device having a compact appearance and good mountability without increasing the manufacturing cost or lowering the product quality in view of the above-mentioned situation. An object of the present invention is to provide a method for manufacturing a device.

[0014]

In order to achieve the above object, a method of manufacturing a semiconductor device according to the present invention comprises a step of mounting a semiconductor chip on a lead frame having a plurality of leads via an insulating adhesive. Connecting the semiconductor chip and the lead to each other via a bonding wire;
A step of resin-sealing the semiconductor chip, the bonding wires, and the sealing area of the lead frame with a package,
The method includes a step of punching an opening facing the lead on the lower surface of the package by laser processing, and a step of providing an external connection terminal electrically connected to the lead through the opening on the lower surface of the package.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing embodiments. A semiconductor device 1 manufactured by the manufacturing method of the present invention shown in FIG. 1 is a BGA (ball grid array) type semiconductor device using a lead frame described later, and a mounting surface (lower surface) of a package 2. The 2a is provided with a large number of solder balls (external connection terminals) 3, 3,... Connected to a semiconductor chip described later.

As shown in FIGS. 2 and 3, the semiconductor device 1 has a plurality of leads 11, 11... Bonded and fixed to the lower surface of a semiconductor chip 4 via an insulating adhesive. Are located at four edges of the semiconductor chip 4.

The semiconductor chip 4 and the leads 11, 11,... Are connected to each other via bonding wires 5, 5,.
11 and the bonding wires 5, 5,... Are resin-sealed by a package 2 formed by molding a mold resin.

Also, solder balls 3, 3,... As external connection terminals are provided at the tips of the leads 11, 11,..., And these solder balls 3, 3,. Openings 2h formed in 2a, 2h ...
, The mounting surface (lower surface) 2a of the package 2 is exposed.

On the other hand, as shown in FIG. 4, a lead frame 10 used when manufacturing the above-described semiconductor device 1 is:
A plurality of leads 1 are respectively formed from the pair of side rails 10S, 10S and the pair of support bars 10B, 10B.
Are formed so as to extend toward the center.

Here, the lead frame 10 is formed by etching or punching, and the leads 11, 11,... Of the lead frame 10 have a flat plate shape and extend on the same plane.

In the lead frame 10,
A region surrounded by an outer edge of the package 2 indicated by a dashed line in the drawing is a sealing region 10P where the package 2 is formed in a manufacturing process described later.

The lead frame 10 according to this embodiment has leads 11, 11 constituting one semiconductor device.
Are formed in only one row between the side rails 10S, 10S. However, the form of the lead frame is not limited to the above-described embodiment, and two rows or more rows of leads constituting one semiconductor device are formed. It may be formed in multiple rows.

Hereinafter, the manufacturing process of the semiconductor device according to the present invention will be described in detail with reference to FIG. First, as shown in FIG. 5A, the semiconductor chip 4 is connected to the lead frame 1.
At a predetermined position (position indicated by a two-dot chain line in FIG. 4) on each of the leads 11, 11,..., Using an insulative adhesive (not shown).

Next, as shown in FIG. 5B, the semiconductor chip 4 and each of the leads 11, 11,... Are individually connected (wire-bonded) using bonding wires 5, 5,.

Next, as shown in FIG. 5C, the semiconductor chip 4, the bonding wires 5, 5,..., And the sealing region 10P in the lead frame 10 are melted in a resin sealing mold (not shown). Is sealed with a package 2 which is molded by filling the molded resin.

FIG. 5 (c) and FIG.
5D and FIG. 5E are cross-sectional side views of the package 2 in which the resin is continuously sealed along the longitudinal direction of the side rails 10S in the lead frame 10 as viewed from the side rail 10S side. .

Next, as shown in FIG. 5D, openings 2h, 2h... For exposing the tips of the leads 11, 11... In the lead frame 10 on the mounting surface (lower surface) 2a of the package 2 by laser processing. Perforate.

Although each of the leads 11, 11,... Is molded inside the package 2, its position can be accurately estimated based on the outer shape of the lead frame 10 as an example. The openings 2h, 2h... Can be formed at predetermined positions of the package 2 by using a laser beam machine.

Further, the perforation of the package 2 by laser irradiation makes it possible to form an opening only in a necessary portion in a short time without damaging the mold resin.

After the openings 2h, 2h,... Are formed in the package 2, molten solder is poured into the openings 2h, 2h, and solidifies to form the tips of the leads 11, 11,. Solder balls exposed on the mounting surface 2a of the package 2 through the openings 2h, 2h.
(External connection terminals) 3, 3,... Are formed.

Next, each lead 1 of the lead frame 10 is
1, 11, ... are cut off at the end face of the package 2,
When the semiconductor device 1 (see FIGS. 1 to 3) is taken out of the lead frame 10, the semiconductor device 1 is completed.

As described above, in the method for manufacturing a semiconductor device according to the present invention, the opening 2h in the mounting surface (lower surface) 2a of the package 2 is perforated by laser processing.
It is not necessary to provide a large number of convex portions for forming the opening 2h in the above-described resin molding die, so that the manufacturing cost of the resin molding die can be reduced and the semiconductor device Can be significantly reduced in manufacturing cost.

Further, in the method of manufacturing a semiconductor device according to the present invention, since the resin molding die is not provided with a large number of projections for forming the opening 2h as described above,
At the time of resin sealing, the mold resin flows smoothly inside the resin sealing mold, thereby producing a semiconductor device having good product quality without resin sealing failure.

In the method of manufacturing a semiconductor device according to the present invention, since a BGA type semiconductor device is manufactured using a lead frame, the wiring board is used as a component while achieving a compact semiconductor device. The manufacturing cost can be reduced compared to the conventional semiconductor device (see FIG. 6).

Further, in the semiconductor device 1 having the above-described structure manufactured according to the present invention, the upper and lower portions of the semiconductor chip 4 resin-sealed by the package 2 have the molding resin, respectively. In addition, when the package 2 is molded at a high temperature, even if there is a difference in the coefficient of thermal expansion between the mold resin and the semiconductor chip 4, the package 2 does not warp and deform with respect to the semiconductor chip 4. , A very good mountability to a printed circuit board can be obtained.

In the above-described embodiment, since the solder balls 3 as the external connection terminals are formed at the tips of the leads 11, no waste is caused in the length of the leads. Can be set at an arbitrary position on the lead 11.

In the process of manufacturing the semiconductor device 1, the step of perforating the openings 2h, 2h... In the package 2 and the step of providing the solder balls 3, 3. It is also possible to carry out in a state where it is taken out.

Each lead 1 is provided on the lower surface of the semiconductor chip 4.
Needless to say, an insulating adhesive tape for fixing and installing 1, 11,... Includes an insulating adhesive tape.

Further, in the semiconductor device 1 in the above-described embodiment, the leads 11
.. On which the semiconductor chip 4 is mounted. Similar to the conventional semiconductor device B shown in FIG. 7, a semiconductor device in which a semiconductor chip is mounted on the pads using a lead frame having a large number of leads and pads. It goes without saying that the present invention can also be effectively applied to manufacturing.

Even in the case of manufacturing the semiconductor device having the above configuration, the steps after mounting the semiconductor chip on the pads of the lead frame are no different from the manufacturing steps of the semiconductor device 1 described above. It goes without saying that the same operation and effect as the accompanying operation and effect can be obtained.

[0041]

As described above in detail, the method of manufacturing a semiconductor device according to the present invention comprises a step of mounting a semiconductor chip on a lead frame having a plurality of leads via an insulating adhesive, and a step of mounting the semiconductor chip and the leads. And a step of connecting the semiconductor chip, the bonding wire and the sealing region of the lead frame with a resin by a package, and punching an opening facing the lead on the lower surface of the package by laser processing. Process and
Providing an external connection terminal electrically connected to the lead through the opening on the lower surface of the package.

According to the above configuration, since the opening in the lower surface of the package is perforated by laser processing, it is not necessary to provide the resin sealing mold with a large number of projections for forming the opening. Therefore, the manufacturing cost of the resin sealing mold can be kept low, and the manufacturing cost of the semiconductor device can be greatly reduced.

Further, as described above, the resin molding die is not provided with a large number of projections for forming an opening, so that the molding resin is not sealed inside the resin molding die during resin sealing. Flows smoothly, so that a semiconductor device having good product quality without resin sealing failure can be manufactured.

Furthermore, in the present invention, since a BGA type semiconductor device is manufactured using a lead frame, the manufacturing cost is reduced as compared with a conventional semiconductor device having a wiring board as a component while achieving a compact semiconductor device. Can be reduced, and good mountability to a printed circuit board can be achieved.

Thus, according to the method for manufacturing a semiconductor device according to the present invention, a semiconductor device having a compact appearance and good mountability can be manufactured without a rise in manufacturing cost and a decrease in product quality. Becomes possible.

[Brief description of the drawings]

FIGS. 1A and 1B are a side view and a bottom view showing a semiconductor device manufactured by a method for manufacturing a semiconductor device according to the present invention.

FIG. 2 (a) is a fragmentary plan view showing a semiconductor device manufactured by a method for manufacturing a semiconductor device according to the present invention,
(b) is a sectional view taken along line bb of (a).

FIG. 3 is a view showing a semiconductor device manufactured by a method of manufacturing a semiconductor device according to the present invention;
II sectional drawing.

FIG. 4 is a plan view of a main part of a lead frame used in the method of manufacturing a semiconductor device according to the present invention.

FIGS. 5A to 5E are conceptual process diagrams showing a method for manufacturing a semiconductor device according to the present invention.

FIG. 6 is a conceptual cross-sectional side view showing a conventional semiconductor device.

FIG. 7 is a conceptual cross-sectional side view showing a conventional semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Semiconductor device, 2 ... Package, 2a ... Mounting surface (lower surface), 2h ... Opening, 3 ... Solder ball (external connection terminal), 4 ... Semiconductor chip, 5 ... Bonding wire, 10 ... Lead frame, 11 ... Lead, 10P: sealing area.

Continued on the front page (72) Inventor Takeshi Takahashi 2-10-1 Komine, Yawatanishi-ku, Kitakyushu-shi, Fukuoka F-term in Mitsui High-Tech Co., Ltd. 4E068 AF00 DA11 5F067 AA01 AA10 AB04 BE10 DE01

Claims (2)

[Claims] A step of mounting a semiconductor chip on a lead frame having a plurality of leads via an insulating adhesive; a step of connecting the semiconductor chip and the leads to each other via bonding wires; And a step of resin-sealing the bonding wire and the sealing region of the lead frame with a package, a step of punching an opening facing the lead on the lower surface of the package by laser processing, and forming the opening on the lower surface of the package. Providing an external connection terminal that is electrically connected to the lead through the semiconductor device. 2. The method according to claim 1, wherein the plurality of leads in the lead frame are cut off at an end face of the package.