JP2681145B2 - Resin-sealed semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-encapsulated semiconductor device in which a semiconductor chip portion is encapsulated with a resin encapsulant and a plurality of external leads are provided from the side of the resin encapsulant.

[0002]

2. Description of the Related Art A conventional semiconductor device of this type is shown in FIG. 5A. 1 is a semiconductor chip such as an IC chip (hereinafter “chip”)
(Hereinafter referred to as)) is die-bonded on the die pad 3 formed on a part of the lead frame by the die bond material 6. Reference numeral 4 is a plurality of inner lead portions, and 5 is an outer lead extended from each inner lead portion and bent. On the peripheral side of the surface of the chip 1, as shown in FIG.
Is formed, and each electrode 2 and each inner lead portion 4 corresponding thereto are wire-bonded with a thin metal wire 7. The thin metal wire 7 has a diameter of 25 to 30 μm. From this state, as shown in FIG. 5A, the chip 1 part is sealed with a resin sealing body (package) 8 formed by transfer molding with epoxy resin or the like.

The wire bonding shown in FIG. 5B is as follows. The thin metal wire 7 is passed through a capillary chip (not shown) of the wire bonding device, and the tip of the thin metal wire 7 protruding from the lower end of the capillary chip is melted to form a spherical shape. The spherical portion of the metal thin wire 7 is pressed and pressed against the 100 μm square electrode (bonding pad) 2 on the chip 1, and the metal diffusion bonding is performed by applying temperature and ultrasonic waves. Subsequently, the capillary chip is moved onto the inner lead portion 4 while feeding out the thin metal wire 7, the thin metal wire 7 is pressed, and metal diffusion bonding is performed in the same manner as above.

In this wire bonding, there are the following constraints. (a) The electrode 2 on the chip 1 is on the peripheral side. (b) The distance between the electrode 2 of the chip 1 and the internal lead portion 4 must be 0.5 mm or more in order to connect them with the thin metal wire 4. (c) The distance between the inner lead portion 4 and the die pad 3 must be 0.2 mm or more from the standpoint of insulation. (d) In order to bond to the inner lead portion 4, the length of the inner lead 4 is
Must be 0.2 mm or more.

As a result, the outer shape of the resin sealing body 8 is
At least the width of the wire bond of the internal lead portion 4 and the length of the interconnection are required between the chip 1 and the encapsulated chip 1. Therefore, in the conventional device of FIG. 5, the outer shape of the resin encapsulant 8 is 0.5 mm or more from the periphery of the chip 1.

The chip 1 such as an IC chip tends to become larger due to the recent higher integration and higher functionality of IC devices. However, due to the demand for downsizing and thinning of electronic equipment, small surface mounting is required. A resin-sealed semiconductor device is required.
FIG. 6 shows the transition of the size of the semiconductor chip 1 and the resin sealing body 8.
The relationship with the external shape is shown. This figure shows an example of a memory IC, which progresses in the order of A → B → C with age, and the resin encapsulation body 8 is in the direction of miniaturization, and the chip 1 is in the direction of contradictory direction. As shown in FIG. C, the distance between the chip 1 and the outer shape of the resin encapsulant 8 is 0.5 mm or less, which cannot be handled by the conventional semiconductor device by wire bonding.

As described above, in order to cope with the increase in the size of the chip 1 and the reduction in the size of the resin encapsulation body 5, the resin encapsulation according to the TAB (Tape Automated Bonding) method shown in FIG. Semiconductor devices have been devised. 8A is a plan view before resin sealing, and FIG. 8B is an enlarged cross-sectional view of the completed semiconductor device. 10 is an insulating tape, on the upper surface of which a plurality of leads 11 made of copper foil or the like are wired. An insulating tape 10 is formed on each of the electrodes 2 on the peripheral side of the chip 1 through a metal bump 12.
The inner ends of the leads 11 are connected. A part of the chip in this state is sealed with a resin sealing body 13.

A conventional wire bonding type semiconductor device corresponding to the TAB type semiconductor device of FIG. 8 is shown in FIGS. 7A and 7B in a plan view before resin sealing and an enlarged sectional view after completion. Chip 1 on die pad 3 by lead frame
Are die-bonded with the die-bonding material 6, and the plurality of electrodes 2 formed on the peripheral side of the chip 1 and the corresponding inner lead portions 4 are wire-bonded with the thin metal wires 7. The chip 1 part in this state is replaced with the internal lead part 4
Including the above, the resin sealing body 8 is used for sealing.

[0009]

In the conventional resin-encapsulated semiconductor device as described above, the one using the wire bonding method has an outer shape of the resin-encapsulated body which requires a considerable distance from the outer periphery of the chip 1 portion, and is miniaturized. There was a problem that it hindered. In the TAB method, the lead 11 is made of copper foil or the like and has a weak strength and requires a special mounting method, which is a mounting method different from the conventional resin-encapsulated semiconductor device shown in FIG. There is a problem that the resin-encapsulated semiconductor device is not compatible.

The present invention has been made in order to solve such a problem, and a plurality of electrodes on the chip surface can be easily connected to internal lead portions in a short time, and a resin encapsulating the chip portion is sealed. The outer shape of the body is smaller than the conventional one, and the position of the electrode on the chip is not restricted by the arrangement of the electrode on the peripheral side for connection with the internal lead portion unlike the conventional one,
It is an object of the present invention to obtain a resin-sealed semiconductor device which can be arranged at a required position and has a high degree of freedom in designing an internal pattern of a chip.

[0011]

[MEANS FOR SOLVING THE PROBLEMS] The electrode position on the chip is arranged at a convenient position from the pattern of the chip without being restricted by the peripheral side, the lead frame does not need a die pad, and the upper surface of the insulating tape is provided. A plurality of connection wirings are formed, and conductive connection portions are provided at both ends of each connection wiring so as to penetrate the front and back sides, and each electrode on the chip and each corresponding internal lead portion are arranged on the insulating tape. The conductive connection portion is joined via a bump, the chip portion and the insulating tape portion are sealed with a resin encapsulant, and the external lead is extended from the side of the resin encapsulant.

[0012]

In the present invention, the insulating tape joins the chip and the internal lead portions to the corresponding conductive connecting portions through the bumps, and the chip does not require die bonding.
By the bump connection method, they are joined at once, and the manufacturing process is greatly shortened. Since bump connection is used instead of wire bonding, the distance between the outer periphery of the chip and the outer shape of the resin sealing body may be smaller than that of the conventional one, and the outer shape can be reduced.

[0013]

1 to 4 show an embodiment of a resin-sealed semiconductor device according to the present invention. In FIG. 3A, 21 is an IC
Semiconductor chips such as chips (hereinafter referred to as "chips")
Then, on the upper surface, a plurality of electrodes 22 are formed in the long side direction at the central portion position in the short side direction. A metal bump 23 is attached on each electrode 22. For the metal bump 23, for example, a solder material or a gold material is used. The electrode 22 part is shown in an enlarged sectional view in FIG. 3B. Reference numeral 24 is a passivation film formed on the surface of the chip 21.

FIG. 4A is a plan view of the lead frame.
A plurality of inner lead portions 26 and outer leads 27 are formed on the strip-shaped lead frame 25, adjacent leads are connected by tie bar portions 28, and are also connected to connecting portions 29 on both sides. A metal bump 30 made of a solder material, a gold material, or the like is attached on each inner lead portion 26. Each internal lead part
In the conventional device, the tip of 26 was extended for wire bonding as shown by a chain line, but in the device of the present invention, it is shortened as a solid line, and each tip is aligned in the direction of arrow C. There is. In addition, the lead frame 25,
The die pad which was conventionally required is not provided. The inner lead portion 26 is shown in cross section in FIG. 4B.

FIG. 2 shows an insulating tape. An insulating tape 31 is made of an insulating material such as polyimide. Through holes are provided in the insulating tape 31 at positions corresponding to the electrodes 22 and the internal lead portions 26 of the chip 21 (see FIG. 1),
These through holes have conductive connection parts 33a made of a metal conductive material.
And 33b are attached through the front and back. Since the conductive connecting portions 33a and 33b are connected to each other, the insulating tape 31
A plurality of connection wirings 32 made of copper foil or the like are formed on the surface.

Bonding by bumps using the chip 21, lead frame 25 and insulating tape 31 formed as described above will be described below. First, as shown in FIG.
Position and fix the lead frame 25 on a table (not shown). Next, the chip 21 is fixed to a fixing base (not shown)
Positioned on top and fixed by vacuum suction etc., lead frame
With respect to 25, the fixed base is moved and rotated in the X and Y axes and adjusted so that the horizontal plane position and the X and Y axis direction positions on the plane and the rotation position become predetermined. In this way, the relative relationship between the connection parts is corrected, and the bumps 23 on the chip 21 and the bumps 30 on the internal lead parts 26 are positioned in height so that they are on the same horizontal plane. In this state, lower the insulating tape 31 from above,
As shown in FIG. 1, each conductive connection portion 33a is applied onto each corresponding bump 23, and each conductive connection portion 33b is connected to each corresponding bump 30.
The bumps and the conductive connecting portions of the insulating tape 31 are collectively joined at one time by pressing on the upper surface and pressing the entire surface of the joint from above with a heated pressing body (not shown).

Thus, the lead frame 25 having the chip 21 and the internal lead 26 connected thereto and the insulating tape
31 and 31 are put in a resin-sealing die device, and are sealed by molding a resin-sealed body 35 as shown in FIG. Then,
The tie bar 28 and the connecting portion 29 of the lead frame 25 are cut by a press, and the external lead 27 is bent by a press work, and the resin-sealed semiconductor device is completed.

[0018]

As described above, according to the present invention, the distance between the outer periphery of the chip and the outer shape of the resin encapsulant can be reduced, the outer shape can be miniaturized, and the resin encapsulant can have the same outer shape. For example, a chip that is larger than the conventional one can be accommodated, and the external leads maintain the same strength as in the conventional wire bond system. In addition, the electrode position on the chip is not restricted to the peripheral side as in the past, but it can be placed in the central part. In this case, the wiring length to the electrode in the chip can be shortened, and the noise resistance is improved at high speed. It Further, the die bonding step of the chip is omitted for the lead frame, the connection of each electrode of the chip and each internal lead is collectively processed, and the manufacturing process is shortened. Furthermore, the die pad of the lead frame is not provided, and the resin sealing body has a chip housing structure in which the die pad is omitted, and the crack resistance due to thermal stress is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a resin-sealed semiconductor device according to the present invention.

FIG. 2 is an exploded perspective view of the device of FIG. 1 before resin sealing.

3 is a perspective view of the semiconductor chip of FIG. 2, and FIG. 3B is an enlarged cross-sectional view of the electrode portion of FIG.

4 is a plan view of the lead frame shown in FIG. 2, and FIG. 4 is a sectional view taken along line BB of FIG.

FIG. 5 is a perspective view showing a conventional resin-encapsulated semiconductor device partially broken away, and FIG. 5 is an enlarged view of a wire bonding portion in FIG.

6A, 6B, 6C, 6D, 6E, 6F, 6G, and 6G are explanatory views sequentially showing a large-scale change in the outer shape of the resin encapsulant as the semiconductor chip becomes larger.

7A and 7B are a plan view before resin encapsulation and a cross-sectional view after resin encapsulation showing another example of a resin-encapsulated semiconductor device according to a conventional wire bonding method.

8A and 8B are a plan view before resin sealing and a cross-sectional view after resin sealing of a conventional TAB type resin-sealed semiconductor device.

[Explanation of symbols]

 21 Semiconductor chip 22 Electrode 23 Metal bump 25 Lead frame 26 Inner lead section 27 External lead 30 Metal bump 31 Insulation tape 32 Connection wiring 33a One conductive connection section 33b Other conductive connection section 35 Resin encapsulant

Claims (1)

(57) [Claims] 1. The inside without being restricted to the peripheral side of the upper surface
Multiple electrodes arranged in the central position according to the pattern
A semiconductor chip having metal bumps attached to each electrode; a die pad is omitted; a plurality of internal lead parts for the semiconductor chip and external leads extended from the internal lead parts are formed. The inner ends of the parts are aligned and a metal bump is attached on each inner end, a plurality of one conductive connection parts corresponding to the bumps of each electrode of the semiconductor chip, and each of the inner leads. A plurality of other conductive connection portions corresponding to the bumps are provided so as to penetrate through the front and back surfaces, and an insulating tape having a plurality of connection wirings for respectively connecting the conductive connection portions on both sides is formed, A semiconductor chip is arranged in the lead frame,
The upper surface of the electrode and the upper surface of the internal lead portion are made to be in the same horizontal plane, covered with the insulating tape from above, and the conductive connection portions are collectively bonded by heating and pressing to the corresponding electrode and internal lead portion via the bumps. The lead frame is provided with a resin encapsulant formed by encapsulating the semiconductor chip section, the internal lead section, and the insulating tape section by removing unnecessary portions of the lead frame. The resin-encapsulated semiconductor device in which the external leads are exposed.