JPH11126854A - Manufacture of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deformations such as warpages from being formed in a substrate, even if a cure is performed after a resin-sealing of a semiconductor chip and leads by a method, wherein after a process of cutting the substrate in a pattern unit, the semiconductor chip and the leads are resin-encapsulated. SOLUTION: A TAB tape 32 is cut by an isolation hole 9 using a metal mold or the like, and an external shape cut part 16 is formed. Then, an individual piece-shaped reinforcing plate 21 with a bonding agent 22 provided on one main surface thereof is pasted on a base film 34 of the tape 32. Then, inner leads 4 and ILB parts 33 are coated on a semiconductor chip 1 with a resin 11 by a potting method or the like, and after that, a cure is performed for 30 to 60 minutes at 150 deg.C. Then, metal balls 13 such as solder balls are bonded to a land 7 by a reflow or the like. An individual piece-shaped heat sink 37 with a bonding agent 36 formed at a prescribed position on one main surface thereof is made to oppose to the chip 1 with a bonding agent 38 formed on the rear thereof and the reinforcing plate 21 and the heat sink 37 is pasted on the chip 1 and the plate 21 via the bonding agents 36 and 38.

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 semiconductor device having a semiconductor chip mounted on a film carrier tape.

[0002]

2. Description of the Related Art A semiconductor device using a conventional film carrier tape is manufactured by the following method. First, a base film is prepared in which an insulating film such as polyimide, polyester, or glass epoxy is formed with a device hole, which is an opening where a semiconductor chip is arranged, and a sprocket hole for transport and positioning. A metal foil made of copper or the like is adhered thereon via an adhesive, and the metal foil is processed into a desired shape by etching or the like, thereby forming a lead having a desired shape and a pad for electrical selection.

A lead (inner lead) projecting into a device hole of a film carrier tape formed as described above and a bump made of a metal projection provided in advance on an electrode terminal of a semiconductor chip are bonded by thermo-compression bonding. Inner lead bonding (ILB: inner)
lead bonding), screening of electrical properties and burn-in test (BT: burn
-in test). Next, the inner lead is connected to an outer lead bond (OLB).
g) Cut to the desired length possible.

Here, in the case of a large number of pins having a large number of leads, a method is often used in which an insulating film is left on the outer ends of the outer leads in order to prevent the outer lead bonding portion of the leads from scattering. . Then, the lead is placed on a bonding pad such as a printed circuit board by OL.
B.

In the method of mounting a semiconductor device using such a film carrier tape, when the leads are mounted on a printed circuit board by OLB, the thickness of the leads is very small, about 35 μm, and thus the coplanarity of the leads is low. In order to cope with this, an OLB bonder dedicated to a film carrier tape was required.

Further, when this semiconductor device is mounted on the same substrate together with another surface mounting package that can be mounted by batch reflow such as QFP, the reflow process cannot be performed. It had to be mounted in a separate process. For this reason, the semiconductor device using the film carrier tape is handled as a special package, and has a problem that it lacks versatility.

On the other hand, the outer reflow pitch of a reflowable QFP or the like is limited to about 0.4 mm pitch. One solution to this limitation is a BGA (Ball Grid Arra) which is a surface mount type package in which solder bumps are arranged in a grid on the back surface of the package as external terminals.
y) has been proposed (see, for example, Nikkei Microdevices, August 1994, pp. 58-64).

This BGA is, for example, a 220 pin class 2
1.5 to implement a 3 to 24 mm square package
mm, which is excellent in mountability as compared with a conventional QFP that requires a pitch of 0.4 mm.
In addition, since the BGA has a small package outer size, the wiring length inside the package can be shortened.
There is a feature that the electrical characteristics are also improved. Substrates used for the BGA include a multilayer printed circuit board, a ceramic substrate, a film carrier tape, and the like.

FIG. 8 is a process diagram showing a method for manufacturing a BGA using a film carrier tape disclosed in, for example, JP-A-8-31866. First, as shown in FIG. 1A, the bumps 2 on the semiconductor chip 1 and the inner leads 4 of the film carrier tape 3 are connected using a bonding tool 5 to form an ILB portion 6.
Here, a land 7 is formed on the base film 3a of the film carrier tape 3, a solder resist 8 is formed on the land 7, and an isolation hole 9 penetrating vertically is formed.

Next, as shown in FIG. 1B, the semiconductor chip 1, the inner leads 4, and the ILB portion 6 are sealed with a resin 11 by a potting method or the like. Then, the suction unit 1
2, metal balls 13 such as solder balls are arranged so as to coincide with the positions of the lands 7 of the film carrier tape 3, and as shown in FIG. To the land 7 by thermocompression bonding or the like.

Next, after selecting characteristics by using an electric characteristic selection pad (not shown) provided on the film carrier tape 3, as shown in FIG. 1 (d), using a cutting tool 15 or the like. Film carrier tape 3
Is cut at the portion of the isolation hole 9 to obtain a semiconductor device 17 having an outer surface cut portion 16 as shown in FIG.

BG using this film carrier tape
As another example of A, as shown in FIG. 9, a film carrier tape 3 having a structure in which a reinforcing plate 21 is attached with an adhesive 22 to a surface opposite to a surface to which metal balls 13 are joined, As shown in FIG. 10, a structure in which a heat radiating plate 23 is attached with adhesives 22 and 24 so as to cover the entire semiconductor chip 1 and the film carrier tape 3 has also been proposed. BGA using this film carrier tape
Is characterized in that the film carrier tape 3 is conveyed by a long film carrier tape 3 until the electrical characteristics are selected, and then the film carrier tape 3 is cut at the isolation hole 9 into individual pieces. is there.

[0013]

By the way, in the conventional method of manufacturing a BGA using a film carrier tape, a long film carrier tape 3 is used until the electrical characteristics are selected. Are cut into individual pieces, but if the resin 11 is cured after sealing with the resin 11 by a potting method or the like, the film carrier tape 3 is liable to be deformed such as warpage due to heat at the time of curing. Therefore, when the metal ball 13 is bonded to the land 7 after the resin 11 is cured, there is a problem that the metal ball 13 is likely to be displaced during the period from the supply to the land 7 to the bonding, and the manufacturing yield is reduced. Was.

In addition, a long film carrier tape 3 is used up to selection of electrical characteristics.
Since this method is for producing a large number of products of the same type while winding up the film carrier tape 3, there is also a problem that it is difficult to handle products of various types in small quantities.

The present invention has been made in view of the above circumstances, and improves the manufacturing yield when manufacturing a semiconductor device in which a semiconductor chip is mounted on a flexible substrate having a wiring pattern formed thereon. It is another object of the present invention to provide a method of manufacturing a semiconductor device which can obtain a semiconductor device with improved reliability, and which can automate a manufacturing process and can cope with a small number of products.

[0016]

In order to solve the above problems, the present invention provides the following method for manufacturing a semiconductor device. That is, a method for manufacturing a semiconductor device in which a semiconductor chip is mounted on a flexible substrate having a wiring pattern formed thereon, wherein a step of connecting an electrode on the semiconductor chip and a lead of the substrate is performed, The method includes a step of cutting in units and a step of resin-sealing the semiconductor chip and the leads.

After the resin sealing step, a step of bonding a conductive protruding electrode on the wiring pattern of the substrate may be provided. Further, a step of attaching a reinforcing plate to the substrate via an adhesive may be provided either before or after the resin sealing step. Further, after the step of bonding the protruding electrodes, a step of attaching a heat sink to the semiconductor chip via an adhesive may be provided.

Further, the substrate may be a film-like substrate having a wiring pattern formed of a metal layer on at least one main surface. Further, the film-shaped substrate may be a film carrier tape having a metal foil wiring layer on at least one main surface of a base film.

In the method of manufacturing a semiconductor device according to the present invention, the method further comprises the step of resin-sealing the semiconductor chip and the leads after the step of cutting the substrate in pattern units, so that curing is performed after resin sealing. Even so, there is no possibility that deformation such as warpage occurs in the substrate, and the occurrence of problems due to the deformation such as warpage is eliminated. Thereby, the manufacturing yield is improved, and the reliability of the obtained product is also improved. Further, by cutting a flexible substrate in units of patterns, it is possible to use an automation line of a manufacturing process which has been conventionally used. In addition, since individual pieces cut in pattern units can be sent to processes required for each product type, it is easy to deal with a small number of products.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the method for manufacturing a semiconductor device according to the present invention will be described with reference to the drawings.

[First Embodiment] FIG. 1 is a process diagram showing a method of manufacturing a semiconductor device according to a first embodiment of the present invention.
First, as shown in FIG. 1A, the electrode 31 on the semiconductor chip 1 and a part of a metal foil wiring layer of a TAB (tapeautomated bonding) tape (film carrier tape) 32 are formed and protrude into the device hole 32a. The inner leads 4 are connected by an ILB method such as a single point method or a gang method to form an ILB unit 33.

The electrode 31 is formed of a thin film of Al or the like, or a metal (A)
u) or other bumps may be formed. Also, TA
The B tape 32 has a land 7 constituting a part of a metal foil wiring layer formed on a long base film 34, a solder resist 8 formed on the land 7, and an isolation hole penetrating vertically. 9 are formed.

Next, as shown in FIG. 2B, the TAB tape 32 is inserted into the isolation holes 9 using a mold or the like.
To form the outer shape cutting portion 16. Next, as shown in FIG. 3C, the individual reinforcing plate 21 provided with the adhesive 22 on one main surface is attached to the base film 34 of the TAB tape 32. Here, the adhesive 22 can be appropriately selected and used such as a room temperature adhesive type, a thermoplastic type, and a thermosetting type.

As the reinforcing plate 21 and the adhesive 22, for example, those having a dimensional relationship shown in FIG. 2 or FIG. 3 are preferably used. In FIG. 2, the adhesive 22 is formed on the entire main surface on the side to which the rectangular frame-shaped reinforcing plate 21 is attached, and the adhesive 22 and the reinforcing plate 21 are formed to have the same dimensions. I have. In FIG. 3, the adhesive 22 is the reinforcing plate 21.
Is formed on the surface except for the side of the main surface on the side to be adhered. For example, the dimension W1 of the reinforcing plate 21 is 5 mm, and the adhesive 2
The size W2 of the adhesive 22 is formed to be smaller than the size W1 of the reinforcing plate 21 so that the size W2 of No. 2 is 3.0 to 3.5 mm.

Next, as shown in FIG. 2D, the surface of the semiconductor chip 1, the inner leads 4 and the ILB portion 33 are coated with a resin 11 by a potting method or the like.
Thereafter, for example, curing is performed at 150 ° C. for 30 to 60 minutes. Next, as shown in FIG. 3E, a metal ball 13 such as a solder ball is supplied onto the land 7, and the metal ball 13 is joined to the land 7 by reflow or the like.

Next, as shown in FIG. 3 (f), an individual heat spreader (radiator plate) 37 having an adhesive 36 formed at a predetermined position on one main surface, and an adhesive 38 formed on the back surface. The semiconductor chip 1 and the reinforcing plate 21 are attached to the semiconductor chip 1 and the reinforcing plate 21 via adhesives 36 and 38 so as to face the semiconductor chip 1 and the reinforcing plate 21. The adhesive 36 can be appropriately selected and used, such as a normal temperature adhesive type, a thermoplastic type, and a thermosetting type, like the adhesive 22 described above. Thus, the assembly process of the semiconductor device is completed.

As the shape of the adhesive 36 on the heat spreader 37, for example, various shapes shown in FIG. 4 are preferably used. FIG. 4A shows an example in which an air hole 41 which is a region without the adhesive 36 is formed at each corner on one diagonal line.
When the outer dimension W3 of the heat spreader 37 is 40 mm, it is 2-3 mm. These air holes 41,
41 is formed in order to prevent the popcorn phenomenon when mounting on a motherboard.

As shown in FIG. 4B, the air holes 41 may be formed at two corners of the heat spreader 37 on two diagonal lines. FIG.
As shown in (c), when the outer dimension W3 of the heat spreader 37 is 40 mm, an adhesive having a length W5 of 15 to 25 mm and a width W6 of 3 to 3.5 mm is attached to the center of each side of the heat spreader 37. An agent 36 may be formed. Alternatively, as shown in FIG. 4D, when the outer dimension W3 of the heat spreader 37 is 40 mm, one side length W7 is provided at each corner of the heat spreader 37.
May be formed with an adhesive 36 having a thickness of 3 to 4 mm.

According to the method of manufacturing a semiconductor device of this embodiment, the electrodes 31 on the semiconductor chip 1 are connected to the inner leads 4 of the TAB tape 32, and then the TAB tape 32
Is cut in the isolation hole 9, and then the semiconductor chip 1, the inner lead 4 and the ILB portion 33 are
Therefore, even if resin sealing and curing are performed, deformation such as warpage of the TAB tape 32 due to heat can be suppressed.

Accordingly, the joining by supply and reflow of the metal balls 13 is stabilized, and the yield in the assembling process can be improved. Also, heat spreader 37
Since the air hole 41, which is a region without the adhesive 36, is formed thereon, the popcorn phenomenon at the time of mounting on the motherboard can be prevented, and the reliability in mounting can be improved.

[Second Embodiment] FIGS. 5 and 6 are process diagrams showing a method for manufacturing a semiconductor device according to a second embodiment of the present invention. First, similarly to the manufacturing method of the first embodiment, the electrodes 31 on the semiconductor chip 1 and the inner leads 4 of the TAB tape 32 are connected to form an ILB 33 (FIG. 5).
(A)) Then, the TAB tape 32 is cut at the isolation hole 9 to form the outer cut portion 16 (FIG. 5).
(B)).

Next, as shown in FIG. 5 (c), the base film 34 of the TAB tape 32 is stuck on a frame-shaped reinforcing plate 51 provided with the adhesive 22 on one main surface. Here, as the frame-shaped reinforcing plate 51, for example, one as shown in FIG. 7 is prepared. In this frame-shaped reinforcing plate 51, a rectangular frame-shaped reinforcing plate portion 53 is connected to a long frame portion 52 via a suspender portion 54, and positioning holes 55 are provided on both sides of the frame portion 52 at predetermined positions. It is formed at intervals.

Here, the relation between the width W11 of the reinforcing plate 53 and the width W12 of the adhesive 22 is W11 = W12 or W12.
12−W11 = 1 to about 2 mm. In addition, the number of the reinforcing plate portions 53 is three in this example, but may be four or another number.

Next, as shown in FIG. 5D, the surface of the semiconductor chip 1, the inner leads 4 and the ILB portion 33 are coated with a resin 11 by a potting method or the like.
Thereafter, for example, curing is performed at 150 ° C. for 30 to 60 minutes to cure the resin 11. Next, as shown in FIG. 5E, a metal ball 13 such as a solder ball is supplied onto the land 7, and the metal ball 13 is joined to the land 7 by reflow or the like.

Next, as shown in FIG. 6F, the suspenders 54 of the frame-shaped reinforcing plate 51 are formed by using a mold or the like.
Is cut to form an outer cut portion 56, thereby forming an individual package 57. Next, as shown in FIG. 6 (g), a piece-shaped heat spreader 37 having an adhesive 36 formed at a predetermined position on one main surface is attached to the semiconductor chip 1 having an adhesive 38 formed on the back surface and a reinforcing plate portion. 53, the semiconductor chip 1 and the reinforcing plate 5 through the adhesives 36 and 38.
Paste on 3. As the shape and size of the adhesive 36 on the heat spreader 37, for example, those having various shapes shown in FIG. 4 are used. Thus, the assembly process of the semiconductor device is completed.

According to the semiconductor device manufacturing method of the present embodiment, the electrodes 31 on the semiconductor chip 1 are connected to the inner leads 4 of the TAB tape 32, and then the TAB tape 32
Is cut, and then the base film 34 of the TAB tape 32 is pasted on the frame-shaped reinforcing plate 51.
Deformation such as warpage of the tape 32 is suppressed, and the attachment and joining of the metal balls 13 can be performed in a stable state. In addition, since the frame-shaped reinforcing plate 51 can be used for conveyance, automation of the assembling process can be easily performed, and
It is possible to easily cope with many kinds in small quantities.

Although the above has been specifically described based on the two embodiments, the present invention is not limited to the above-described first and second embodiments, and can be variously modified. For example, the heat spreader 37 may be omitted if it is not necessary due to thermal resistance or the like. Further, as in the two embodiments described above, not only a one-metal film carrier tape having a metal foil wiring layer on only one surface of the TAB tape 32 but also a TAB tape 32 may be used.
A film carrier tape having a two-metal structure in which a signal and power supply wiring layer is formed on one surface and a ground wiring layer is formed on the opposite surface may be used.

In connection with the description of the claims, the present invention can further take the following aspects. (1) The reinforcing plate is a flexible reinforcing plate. (2) The flexible reinforcing plate is a frame-shaped reinforcing plate. (3) The adhesive is formed on either the entire surface of the main surface on the side to which the reinforcing plate is attached or on a surface excluding a side portion of the main surface. (4) An air hole, which is a region without adhesive, is formed on the heat sink.

[0039]

As described above, according to the method of manufacturing a semiconductor device of the present invention, after the step of cutting the substrate in pattern units, the step of resin sealing the semiconductor chip and the lead is provided. Even if curing is performed after sealing, there is no possibility that deformation such as warpage occurs in the substrate, and it is possible to prevent the occurrence of troubles caused by deformation such as warpage. Therefore, the production yield can be improved, and the reliability of the obtained product can be improved.
Further, since the flexible substrate is cut in pattern units, it is easy to automate the manufacturing process and to cope with a small number of products.

[Brief description of the drawings]

FIG. 1 is a process chart showing a method for manufacturing a semiconductor device according to a first embodiment of the present invention.

FIGS. 2A and 2B are diagrams illustrating an example of a dimensional relationship between a reinforcing plate and an adhesive of the semiconductor device according to the first embodiment of the present invention, wherein FIG. 2A is a plan view and FIG.

FIG. 3 is a diagram illustrating another example of the dimensional relationship between the reinforcing plate and the adhesive of the semiconductor device according to the first embodiment of the present invention;
(A) is its top view, (b) is its side view.

FIG. 4 is a plan view showing various shapes of an adhesive on a heat spreader of the semiconductor device according to the first embodiment of the present invention.

FIG. 5 is a process chart illustrating a method for manufacturing a semiconductor device according to a second embodiment of the present invention.

FIG. 6 is a process chart illustrating a method for manufacturing a semiconductor device according to a second embodiment of the present invention.

FIG. 7 is a plan view showing a frame-like reinforcing plate of a semiconductor device according to a second embodiment of the present invention.

FIG. 8 shows a BG using a conventional film carrier tape.
It is a process figure showing the manufacturing method of A.

FIG. 9 shows a BG using a conventional film carrier tape.
It is sectional drawing which shows another example of A.

FIG. 10 shows B using a conventional film carrier tape.
It is sectional drawing which shows another example of GA.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Semiconductor chip 2 Bump 3 Film carrier tape 3a Base film 4 Inner lead 5 Bonding tool 6 ILB part 7 Land 8 Solder resist 9 Isolation hole 11 Resin 12 Suction part 13 Metal ball 15 Cutting tool 16 External cutting part 17 Semiconductor device 21 Reinforcement Plate 22 Adhesive 23 Heat sink 24 Adhesive 31 Electrode 32 TAB tape (Film carrier tape) 32a Device hole 33 ILB part 34 Base film 36 Adhesive 37 Heat spreader (Heat radiator) 38 Adhesive 41 Air hole 51 Frame-shaped reinforcement Plate 52 Frame part 53 Reinforcement plate part 54 Suspender part 55 Positioning hole 56 External cutting part 57 Package

Claims (6)

[Claims] 1. A method of manufacturing a semiconductor device in which a semiconductor chip is mounted on a flexible substrate having a wiring pattern formed thereon, the method comprising: connecting an electrode on the semiconductor chip to a lead of the substrate; A method of manufacturing a semiconductor device, comprising: a step of cutting the substrate in pattern units; and a step of resin-sealing the semiconductor chip and the leads. 2. The method of manufacturing a semiconductor device according to claim 1, further comprising, after the step of sealing with a resin, a step of joining a protruding electrode having conductivity on the wiring pattern of the substrate. 3. The semiconductor device according to claim 1, further comprising a step of attaching a reinforcing plate to the substrate via an adhesive before or after the step of resin sealing. Production method. 4. The method according to claim 2, further comprising the step of attaching a heat sink to the semiconductor chip via an adhesive after the step of joining the protruding electrodes. 5. The method for manufacturing a semiconductor device according to claim 1, wherein the substrate is a film-like substrate having a wiring pattern formed of a metal layer formed on at least one main surface. 6. The method according to claim 5, wherein the film substrate is a film carrier tape having a metal foil wiring layer on at least one main surface of a base film.