JP3445930B2 - 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-sealed semiconductor device in which a semiconductor chip and signal connection leads connected to the semiconductor chip are sealed with a sealing resin, and a die pad is embedded in the sealing resin, and to manufacture the same. The present invention relates to a method, and more particularly to improvement of a thin type.

[0002]

2. Description of the Related Art In recent years, in order to cope with miniaturization of electronic equipment, it has been required to mount semiconductor parts mounted on the electronic equipment at a high density, and accordingly, the miniaturization and thinning of semiconductor parts have been advanced. I'm out.

A conventional resin-sealed semiconductor device will be described below.

FIG. 21 is a sectional view of a conventional resin-sealed semiconductor device. As shown in FIG. 21, the conventional resin-encapsulated semiconductor device is a resin-encapsulated semiconductor device of a type having external electrodes on the back surface side.

A conventional resin-sealed semiconductor device includes an inner lead 101, a die pad 102 upset with respect to the inner lead 101, and the die pad 10.
And a lead frame composed of a suspension lead (not shown) that supports the wire 2. Then, the semiconductor chip 104 is bonded onto the die pad 102 with an adhesive,
The electrode pads (not shown) of the semiconductor chip 104 and the inner leads 101 are electrically connected by the fine metal wires 105. The die pad 102, the semiconductor chip 104, a part of the inner lead 101, the suspension lead and the thin metal wire 105 are sealed with a sealing resin 106. In this structure, the sealing resin 106 does not exist on the back surface side of the inner lead 101, the back surface side of the inner lead 101 is exposed, and the lower portion of the inner lead 101 including this exposed surface becomes the external electrode 107. There is. In addition,
In order to ensure adhesion with the sealing resin 106, the inner side surface of the inner lead 101 is not orthogonal to the front and back surfaces, but is tapered so as to expand upward.

The die pad 102 is upset with respect to the inner lead 101 by depressing the suspension leads. Therefore, the sealing resin 106
Is also thinly formed on the back side of the die pad.

In the manufacturing process of the resin-sealed semiconductor device having the structure shown in FIG. 21, first, the inner lead 1
01 or a lead frame having an upset die pad 102 is prepared and mechanically or chemically processed to taper the side surfaces of the inner leads. next,
After the semiconductor chip 104 is bonded on the die pad 102 of the prepared lead frame with an adhesive, the semiconductor chip 104 and the inner lead 101 are electrically connected by the fine metal wire 105. As the metal thin wire 105, an aluminum thin wire, a gold (Au) wire, or the like is appropriately used. next,
The die pad 102, the semiconductor chip 104, the inner lead 101, the suspension lead and the thin metal wire 105 are sealed with the resin 1.
Seal with 06. In this case, the lead frame to which the semiconductor chip 104 is bonded is housed in the sealing mold,
Although transfer molding is performed, resin sealing is performed particularly in a state where the back surface of the lead frame is in contact with the upper mold or the lower mold of the sealing mold. Finally, the outer leads protruding outward from the sealing resin 106 after resin sealing are cut to complete the resin-sealed semiconductor device.

[0008]

However, in the conventional resin-encapsulated semiconductor device described above, since the encapsulating resin exists below the die pad, it is necessary to reduce the thickness of the entire semiconductor device. The thickness of the semiconductor chip 104 may be reduced, the height of the metal thin wire 105 connecting the electrode on the semiconductor chip 104 and the inner lead 101 may be lowered, or the shape of the metal thin wire 105 may be special. There was a need. As a result, the productivity of the resin-encapsulated semiconductor device deteriorates, which is a factor that hinders the reduction in thickness.

Further, since resin burrs that deteriorate the mountability on the mounting substrate are formed on the lower surface of the external electrodes, it is necessary to introduce a process such as a water jet to remove the burrs. The productivity of semiconductor devices has been getting worse.

The present invention has been made in view of the above points, and an object thereof is to provide an external electrode on the back surface of a sealing resin and to have a structure in which a semiconductor chip is embedded in the sealing resin. the resin-sealed semiconductor equipment suitable for thinning
To provide.

[0011]

The first resin-encapsulated semiconductor device of the present invention In order to achieve the above object, according a da Ipaddo, a plurality of suspension leads for supporting the die pad, a lead signal connection,
An electrode pad on a main surface, is supported by the bottom surface of the die pad in a state with its major surface downward, from the die pad
A semiconductor chip having a large area, a connecting member for electrically connecting the electrode pad of the semiconductor chip and the signal connecting lead, the die pad, the semiconductor chip, the signal connecting lead and the connecting member. and a sealing resin for, the portion of the signal connecting leads are functioning as external terminals exposed on the back surface side of the sealing resin, the die pad is embedded in the sealing resin, the Die
The pad and the semiconductor chip of the suspension lead are mounted.
The area that is formed is thinly formed by half etching.
The two have the same thickness .

The semiconductor of the die pad and the suspension lead
The area where the chip is mounted is the half-edge from the bottom side.
It is preferable that

Each of the above-mentioned suspension leads is arranged above the die pad.
Since the suspension leads are provided between the signal connection leads, the suspension leads of the suspension leads are different from those of the suspension lead provided between the corner portion of the die pad and the outer frame. Since the length can be greatly shortened, the strength of the suspension lead can be largely secured. Therefore, even when a large area die pad is required, it is possible to suppress the deformation of the die pad due to the flow of the sealing resin or the like. Particularly in a thin resin-encapsulated semiconductor device, deformation of the die pad increases the risk of exposing the die pad from the encapsulating resin, but the present invention can prevent such a problem.

[0014] The upper SL each hanging lead, can be processed, such as more and this provided some bending unit, to remove some of the suspension lead at any time after the resin sealing step Becomes

The upper SL Each hanging leads, semiconductor chips and more that you have been cut in some above, it is possible to avoid electrical conduction between the lead hanging the die pad, equipped with bipolar transistors The structure can be applied to.

[0016] More and this the vicinity of the cut has been that portion of the upper Symbol each hanging lead is thin, some of the cutting of the suspension lead by a laser cutting is facilitated structure.

A second resin-encapsulated semiconductor device of the present invention is
And da Ipaddo, a plurality of suspension leads for supporting the die pad, a lead signal connection, the electrode pads on the main surface, is supported by the bottom surface of the die pad in a state with its main surface down A semiconductor chip, a connecting member for electrically connecting the electrode pad of the semiconductor chip and the signal connecting lead, and a sealing resin for sealing the die pad, the semiconductor chip, the signal connecting lead and the connecting member. A part of the signal connection lead is exposed on the back surface side of the sealing resin and functions as an external terminal, the die pad is embedded in the sealing resin, and a part of each suspension lead is provided. is not exposed at the back surface side of the sealing resin, a part which is the exposed functions as an external terminal for reinforcement, the
In the second resin-sealed semiconductor device, each hanging
Of the reinforcing external terminal in the
The bottom surface of the external terminal is
Are running.

This improves the connection strength when the resin-sealed semiconductor device is mounted on the mounting board. For example, in the type in which the electrodes on the mounting board and the external electrodes of the resin-sealed semiconductor device are connected by solder, the external terminals for reinforcement of the resin-sealed semiconductor device and the dummy terminals on the mounting board are used. By interposing solder between them, the connection strength between the two is improved. Then, for example, the self-alignment property when the resin-sealed semiconductor device is mounted on the mounting substrate via the molten solder is improved, so that the mounting time is shortened and the mounting position accuracy is improved.

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The resin-encapsulated semiconductor device of the present invention has a common structure in which a die pad is embedded in an encapsulating resin, and various embodiments will be described below.

(First Embodiment) FIG. 1 is a sectional view of a resin-sealed semiconductor device according to the first embodiment. However, in FIG. 1, the sealing resin 17 is treated as a transparent body, and illustration of each suspension lead is omitted.

As shown in FIG. 1, the resin-sealed semiconductor device according to the present embodiment has a signal connecting lead 12, a die pad 13 for supporting a semiconductor chip, and a suspension lead for supporting the die pad 13. It is equipped with a lead frame. A semiconductor chip 15 having electrode pads (not shown) arranged on the main surface is bonded to the lower surface of the die pad 13 with an adhesive with the main surface facing downward. The lower surface of the signal connecting lead 12 is electrically connected to each other by a thin metal wire 16. Then, the signal connecting leads 12,
The die pad 13, the suspension leads, the semiconductor chip 15, and the thin metal wires 16 are sealed in a sealing resin 17.

Here, the first feature of this embodiment is that the thickness of the die pad 13 is thinned by half etching or the like, the die pad 13 is upset, and the die pad 13 is embedded in the sealing resin 17. That is the point. Therefore, in the state of being sealed with the sealing resin 17, the sealing resin 17 is thin above the die pad 13.

The second feature of the present embodiment is that the inner surface of the signal connecting lead 12 close to the semiconductor chip 15 is half-etched on the lower surface to make it thinner. The height position is higher than the height position of the lower surface of the outer portion, and the metal thin wire 16 connects between the lower surface of the inner portion of the signal connecting lead 12 and the electrode pad of the semiconductor chip. It is a point that is configured in.

Further, the third feature of this embodiment is that the lower surface of the outer portion of the signal connecting lead 12 is exposed on the back surface side of the sealing resin 17, and the outer portion of the signal connecting lead 12 is exposed. Is the connection surface with the mounting substrate, that is, the lower part of the outer portion of the signal connection lead 12 is the external electrode 18. The external electrode 18 exposed from the sealing resin does not originally have a resin burr that is a resin protruding portion in the resin sealing step, and the external electrode 18 is lower than the back surface of the sealing resin 17. A little overhanging. Such a structure of the external electrode 18 having no resin burr and protruding downward can be easily realized by the manufacturing method described later.

According to the resin-sealed semiconductor device of this embodiment, since the die pad 13 is embedded in the sealing resin 17, the sealing resin 17 also exists thinly above the die pad 13. Therefore, the holding force of the sealing resin 17 with respect to the die pad 13 is increased, and the reliability of the resin-sealed semiconductor device is improved, as compared with the case where the upper and lower surfaces of the die pad are exposed from the sealing resin.

Moreover, since the die pad 13 is thinned by half-etching or the like, there is an advantage that the entire resin-sealed semiconductor device can be thinned without thinning the semiconductor chip 15. . That is, restrictions on the type and number of semiconductor elements such as transistors provided in the semiconductor chip 15 which are caused by thinning the semiconductor chip 15 can be relaxed, high performance can be maintained, and the application field is expanded.

Further, the inner portion of the signal connecting lead 12 is half-etched from the lower surface side so that the lower surface of the inner portion and the electrode pad on the main surface of the semiconductor chip 13 facing downward are connected by the fine metal wire 16. With such a structure, the narrow space can be efficiently utilized so that the thin metal wire 16 can be formed so as not to protrude from the sealing resin.

In this embodiment, there is no outer lead as an external electrode terminal on the side of the sealing resin 17,
Since the lower portion of the signal connecting lead 12 corresponding to the inner lead is the external electrode 18, the semiconductor device can be downsized. Moreover, since there is no resin burr on the lower surface of the external electrode 18, the reliability of bonding with the electrode of the mounting substrate is improved. Further, since the external electrode 18 is formed so as to project from the surface of the sealing resin 17, the external electrode 18 is bonded to the electrode of the mounting substrate when mounting the resin-sealed semiconductor device on the mounting substrate. This means that the standoff height of is secured in advance. Therefore,
The external electrode 18 can be used as it is as an external terminal, and it is not necessary to attach a solder ball to the external electrode 18 for mounting on the mounting substrate, which is advantageous in terms of manufacturing steps and manufacturing cost.

Next, a method of manufacturing the resin-encapsulated semiconductor device of this embodiment will be described with reference to the drawings. 2 to 6 are cross-sectional views showing the manufacturing process of the resin-encapsulated semiconductor device of this embodiment.

First, in the step shown in FIG. 2, the signal connecting leads 12 and the die pad 1 for supporting the semiconductor chip are formed.
A lead frame 20 provided with 3 and 3 is prepared.
In the figure, the die pad 13 is supported by suspension leads, but the suspension leads are not shown because they do not appear in this section. By bending the suspension leads upward, the die pad 13 is upset so as to be located above the outer frame. The outer side of the signal connecting lead 12 is connected to the outer frame of the lead frame 20, but since the outer frame is continuous with the signal connecting lead,
No boundary appears on this step. Here, the die pad 13 is entirely thinned by half etching. Furthermore, the lead frame 20 to be prepared is
The lead frame does not have a tie bar for stopping the outflow of the sealing resin.

In addition, the lead frame 20 in the present embodiment has a nickel (Ni) layer as a base plating, a palladium (Pd) layer thereon, and a thin film as the uppermost layer, with respect to a frame made of a copper (Cu) material. 3 is a metal-plated lead frame in which gold (Au) layers are plated. However, other than copper (Cu) material, 42 alloy material and the like can be used, and may be plated with a noble metal other than nickel (Ni), palladium (Pd), and gold (Au). It is not always necessary to use three-layer plating.

Next, in the step shown in FIG. 3, the semiconductor chip 15 is placed on the lower surface of the die pad 13 of the prepared lead frame, and the two are bonded to each other with an adhesive. This process is a so-called die bonding process. Incidentally, the member for supporting the semiconductor chip is not limited to the lead frame, a member capable of supporting other semiconductor chips,
For example, a TAB tape or a substrate may be used.

Then, in the process shown in FIG. 4, the die pad 1
The electrode pads on the main surface of the semiconductor chip 15 which is bonded to the lower surface of the lower surface 3 of the semiconductor chip 15 and the lower surface of the inner portion of the signal connecting lead 12 are electrically bonded to each other by the fine metal wires 16. This process is a so-called wire bond process. As the metal thin wire, an aluminum thin wire, a gold (Au) wire, or the like can be appropriately selected and used.

Next, in a step shown in FIG. 5, with the semiconductor chip 15 bonded to the die pad 13 of the lead frame, the sealing tape 21 is attached to the lower surface of the external electrode 18 of the signal connecting lead 12.

The sealing tape 21 serves to serve as a mask for preventing the sealing resin from wrapping around around the lower surface of the external electrode 18 of the signal connection lead 12 during resin sealing. Due to the presence of the sealing tape 21, it is possible to prevent the resin burr from being formed on the lower surface of the external electrode 18. This sealing tape 21 is a resin-based tape containing polyethylene terephthalate, polyimide, polycarbonate or the like as a main component, and can be easily peeled off after resin sealing and is resistant to a high temperature environment during resin sealing. If there is In this embodiment, a tape containing polyethylene terephthalate as a main component is used, and the thickness is 50 [μm].

Next, in the step shown in FIG. 6, the semiconductor chip 1
The lead frame to which 5 is bonded and the sealing tape 21 is attached is housed in a mold, and the sealing resin 17 is poured into the mold to perform resin sealing. Alternatively, the sealing tape 21 can be attached in the mold. At this time, so that the sealing resin 17 does not go around to the lower surface side of the external electrode 18,
The outer side (outer frame) of the lead 12 for signal connection of the lead frame is pressed downward with a die to seal with resin. Further, there is a gap between the upper surface of the die pad 13 and the die surface, and the resin sealing step is performed so that the sealing resin 17 is sufficiently spread over the die pad 13.

Finally, the sealing tape 21 attached to the lower surface of the external electrode 18 is removed by peeling off. As a result, a structure in which the sealing resin 17 exists above the die pad 13 is obtained. An external electrode 18 protruding downward from the lower surface of the sealing resin 17 is formed on the back surface side of the sealing resin 17. Then, the tip end side of the signal connecting lead 12 is cut off so that the tip end surface of the signal connecting lead 12 and the side surface of the sealing resin 17 are substantially flush with each other, so that the resin sealing type as shown in FIG. The semiconductor device is completed.

According to the manufacturing method of this embodiment, it is possible to easily manufacture the resin-sealed semiconductor device in which the entire die pad 13 is formed thin and the sealing resin 17 is present above the die pad 13. it can.

Moreover, according to the manufacturing method of the present embodiment,
Since the sealing tape 21 is attached to the lower surface of the external electrode 18 of the signal connecting lead 12 in advance before the resin sealing step, the sealing resin 17 does not go around and the lower surface of the external electrode 18 has a resin burr. Does not occur. Therefore, it is not necessary to remove the resin burr formed on the external electrode 18 by a water jet or the like unlike the conventional method for manufacturing a resin-sealed semiconductor device in which the lower surface of the signal connection lead is exposed. That is, by omitting the troublesome process for removing the resin burr, it is possible to simplify the process in the mass production process of the resin-encapsulated semiconductor device. Further, conventionally, nickel (Ni) in the lead frame, which may be generated in the resin burr removal process using a water jet,
Peeling off of metal plating layers such as palladium (Pd) and gold (Au) and adhesion of impurities can be eliminated. Therefore, it is possible to pre-plat each metal layer before the resin sealing step.

Although the resin burr removing step by the water jet can be omitted, a step of attaching the sealing tape is newly required, but the step of attaching the sealing tape 21 is more preferable than the water jet step. Since the cost is low and the process control is easy, the process can be surely simplified. Above all, in the conventionally required water jet process, the metal plating of the lead frame is peeled off, and quality problems such as the adhesion of impurities occur, but in the method of the present embodiment, by applying the sealing tape, The fact that the water jet is unnecessary and the plating can be removed is a great process advantage. In addition, even if resin burrs may occur due to the sealing tape attachment state, etc., since it is an extremely thin resin burr, it is possible to remove the resin burrs by water jet processing with low water pressure and prevent plating peeling. A layer pre-plating process is possible.

After the resin sealing step, the laser beam is radiated from above the sealing tape 21 with the sealing tape 21 still attached to the side surface of the sealing resin 17 of the signal connection lead 12 so as to project. You may cut the existing part. In this way, since the periphery of the cut portion of the lead frame is covered with the sealing tape, even if the melted material due to the laser scatters around, the scattered tape can be peeled off to remove the scattered material from the resin-sealed semiconductor device. There is an advantage that it can be easily removed from.

As shown in FIG. 6, in the resin sealing step, the sealing tape 21 is softened and thermally contracted by the heat of the sealing die, so that the external electrode 18 greatly cuts into the sealing tape 21. A step is formed between the lower surface of the external electrode 18 and the back surface of the sealing resin 17. Therefore, the external electrode 18 has a structure protruding from the back surface of the sealing resin 17, and the protruding amount of the external electrode 18 (standoff height).
Can be secured. For example, in this embodiment, the sealing tape 2
Since the thickness of 1 is 50 μm, the standoff height can be set to about 20 μm, for example. Thus, the standoff height of the external electrode 18 can be maintained at an appropriate amount by adjusting the thickness of the sealing tape 21. This means that the external electrode 1
8 means that the standoff height can be controlled only by setting the thickness of the sealing tape 21, and no means or process for controlling the standoff height amount needs to be separately provided. This is an extremely advantageous point in terms of cost. The thickness of this sealing tape 21 is 10
It is preferably about 150 μm.

Regarding the sealing tape 21 used,
A material having a predetermined hardness, thickness, and heat-softening property can be selected according to a desired standoff height.

However, in the first embodiment, the external electrode 1 is adjusted by adjusting the pressure applied to the sealing tape 21.
The standoff height of 8 may be adjusted, for example, it is also possible to make the standoff height almost "0".

(Second Embodiment) Next, a second embodiment will be described. The resin-encapsulated semiconductor device in this embodiment may have any structure in each embodiment, but is different only in the shape of the die pad and the shape of the connecting portion between the die pad and the suspension lead. Therefore, in the present embodiment, description of other parts except the die pad and the suspension leads connected thereto is omitted.

-First Specific Example- FIG. 7A is a plan view of a die pad 13 according to a first specific example of the present embodiment, and FIG. 7B is a VIIb-shown in FIG. 7A.
FIG. 7 is a sectional view taken along line VIIb. As shown in FIGS. 7A and 7B, the die pad 13 according to the present specific example is formed to have a small thickness by half etching (in the present embodiment, half etching is performed from the lower surface side). The area is smaller than that of the semiconductor chip 15. Also, die pad 1
The thickness of the suspension lead 14 that supports 3 is also the same as that of the die pad 13 in the portion connected to the die pad 13. However, half etching is not performed outside the portion away from the die pad 13.

According to the resin-sealed semiconductor device of the first specific example of the present embodiment, the semiconductor chip 15 has a larger area than the die pad 13, so that the die pad 1
The presence of the sealing resin on the side of 3 and in the region above the semiconductor chip 15 significantly improves the holding force of the sealing resin 17 with respect to the semiconductor chip 15. As a result, the holding force of the sealing resin 17 with respect to the die pad 13 bonded to the semiconductor chip 15 is also improved, so that it is possible to improve the reliability while reducing the thickness of the resin-sealed semiconductor device.

Further, since the thickness of the suspension lead 14 is the same as the thickness of the die pad 13, it is possible to surely realize the thinning of the entire resin-sealed semiconductor device. In that case, it is advantageous that the suspension leads 14 are half-etched from the lower surface side, even if the semiconductor chip 15 having a larger area than the die pad 13 is mounted, interference between the suspension leads 14 and the semiconductor chip 15 can be easily avoided. is there.

FIG. 8 is a plan view showing only the die pad and the suspension leads of the resin-sealed semiconductor device according to the modified example of this specific example. The plane shape of the die pad 13 according to this specific example does not have to be a rectangle as shown in FIG. 7A, but may be a shape as shown in FIG. That is, the die pad 13 may be a single disc provided in the central portion or a disc in the central portion to which four discs (see broken lines) provided in each corner are further added.

-Second Specific Example- FIG. 9A is a plan view of a die pad 13 according to a second specific example of the present embodiment, and FIG. 9B is IXb-IX shown in FIG. 9A.
It is sectional drawing in line b. As shown in FIGS. 9A and 9B, the die pad 13 according to this specific example has a rectangular opening 30a formed in the central portion. This opening 30a
Are formed inside the mounting region of the semiconductor chip 15. Further, the die pad 13 is thinly formed by half etching or the like.

In the resin-sealed semiconductor device according to the second specific example of the present embodiment, since the opening 30a is formed in the die pad 13, the area inside the opening 30a and above the semiconductor chip 15 is formed. Since the sealing resin 17 is present, the holding force of the sealing resin 17 with respect to the semiconductor chip 15 and the die pad 13 is significantly improved.

As shown in the modification of FIG. 10A, an opening 30b surrounded by a frame having a circular area at a corner and an opening 30c surrounded by a frame having a rectangular area at a corner. It may be the die pad 13 having.

(Third Embodiment) Next, each specific example of the third embodiment relating to the structure of the signal connecting lead will be described.

-First Specific Example- FIG. 11 is a sectional view of a resin-sealed semiconductor device according to a first specific example of the third embodiment. As shown in the figure, the inner portion of the signal connection lead 12 is half-etched from the lower surface side to be thinner than the outer portion, and the metal between the lower surface of the inner portion and the semiconductor chip 15 is reduced. A thin wire 16 is provided. Two groove portions 31 are provided on the upper surface of the outer portion of the signal connecting lead 12, that is, above the external electrode 18. Further, although not shown, a portion of the outer portion of the signal connecting lead 12 where the groove is formed is wider than the lower portion.

As in this example, the signal connecting lead 12
By half-etching the inner part of the from the bottom side,
Since the height position of the lower surface of the inner portion is higher than the height position of the lower surface of the outer portion, a certain amount of space is provided between the lower surface of the inner portion and the back surface of the sealing resin 17 without increasing the overall thickness. Can be secured. Therefore, even if one end of the thin metal wire 16 is connected to the lower surface of the inner portion of the signal connecting lead 12,
The thin metal wire 16 can be reliably embedded in the sealing resin 17.

That is, it is possible to prevent the thin metal wires 16 from being exposed from the sealing resin 17 while making the resin-sealed semiconductor device thin.

Moreover, since the sealing resin 17 wraps around the inner side of the signal connecting lead 12, the holding force of the sealing resin 17 with respect to the signal connecting lead 12 also increases.

Further, by providing the groove portion 31 on the upper surface of the outer portion of the signal connecting lead 12, the holding force of the sealing resin 17 with respect to the signal connecting lead 12 is increased, and the outside of the signal connecting lead 12 is increased. By making the width of the upper part of the one part wider than that of the lower part, the holding force of the sealing resin 17 is further increased.

-Second Specific Example- FIG. 12 is a sectional view of a resin-sealed semiconductor device according to a second specific example. As shown in the figure, in this specific example, the inner portion of the signal connecting lead 12 is half-etched from the lower surface side, and the inner portion is upset, and the lower surface of the upset portion is One end of the thin metal wire 16 is connected to.

In this specific example, the inner portion of the signal connecting lead 12 can be brought closer to the semiconductor chip 15 as compared with the first specific example, so the reliability of the metal thin wire 16 is improved. Further, since a sufficient space is secured below the inner portion of the signal connecting lead 12, the thin metal wire 16 can be reliably embedded in the sealing resin 17, and the thin metal wire 16 is exposed from the sealing resin 17. Can be prevented more reliably.

-Third Specific Example- FIG. 13 is a sectional view of a resin-sealed semiconductor device according to a third specific example. As shown in the figure, in this specific example, the signal connecting lead 12 is not half-etched, but the inner portion of the signal connecting lead 12 is set up more than the outer portion thereof.

Also in this example, the signal connecting lead 1 is used.
Since the inner part of 2 can be brought close to the semiconductor chip 15, the reliability of the wire bonding of the thin metal wires 16 is improved. Further, since a sufficient space is secured below the inner portion of the signal connecting lead 12, the thin metal wire 16 can be reliably embedded in the sealing resin 17, and the thin metal wire 16 is exposed from the sealing resin 17. Can be reliably prevented.

-Fourth Specific Example- FIG. 14 is a sectional view of a resin-sealed semiconductor device according to a fourth specific example. As shown in the figure, in this specific example, the signal connecting leads 12 are half-etched from the lower surface side,
In addition, the inner portion of the signal connecting lead 12 extends to a region below the semiconductor chip 15. In addition, the semiconductor chip 1
The electrode pads (not shown) on the main surface of No. 5 are arranged not in the vicinity of the outer periphery of the semiconductor chip but in a region near the center thereof. Then, a thin metal wire 16 is provided between the electrode pad of the semiconductor chip and the lower surface of the inner portion of the signal connecting lead 12.

In this example, since the inner portion of the signal connecting lead 12 can be brought close to the position where the electrode pads of the semiconductor chip 15 are arranged, the length of the thin metal wire 16 can be shortened. Therefore, it is possible to improve the reliability and characteristics of wire bonding of the thin metal wires 16 while making the resin-sealed semiconductor device thinner.

Needless to say, in the fourth specific example, the inner portion of the signal connecting lead 12 may be upset.

(Fourth Embodiment) Next, a fourth embodiment will be described. In this embodiment, a specific example of the structure of the die pad 13 for further thinning will be described.

-First Specific Example- FIG. 15 is a sectional view of a resin-sealed semiconductor device according to a first specific example of the fourth embodiment. As shown in the figure, the die pad 13 is provided only on the side of the semiconductor chip 15, and supports the semiconductor chip 15 from the main surface side, that is, the lower surface side of the semiconductor chip 15. The inner portion of the signal connection lead 12 is half-etched from the lower surface side to be thinner than the outer portion, and extends to the lower region of the semiconductor chip 15. Further, an electrode pad is arranged in the central portion of the main surface of the semiconductor chip 15, and a thin metal wire 16 is provided between the electrode pad and the lower surface of the inner portion of the signal connecting lead 12.

17A and 17B show the die pad 13
It is a top view which shows the example of the planar shape of. As shown in FIG. 17A, a die pad including four rectangular portions isolated from each other may be provided only in the vicinity of a corner of the side portion of the die pad, or as shown in FIG. 17B, two side portions may be provided. It may be a die pad 13 composed of two strip-shaped portions extending along. Further, the semiconductor chip 1 is formed by the die pad 13 having a planar shape as shown in FIGS.
The main surface side of 5 may be supported.

As in this example, the die pad 13 supports the semiconductor chip 15 at the side of the main surface thereof, and the inner portion of the signal connection lead 12 is extended to the lower region of the semiconductor chip 15 so that the metal wire With the structure in which 16 is connected to the lower surface of this inner portion, the space between the semiconductor chip and the signal connecting lead 12 can be used very effectively. As a result, the overall thickness of the resin-sealed semiconductor device can be made thinner and smaller.

In this case, the height position of the lower surface of the inner portion is higher than the height position of the lower surface of the outer portion by half-etching the inner portion of the signal connecting lead 12 from the lower surface side. Therefore, it is possible to secure a certain amount of space with the back surface of the sealing resin 17 without increasing the overall thickness. Therefore, even if one end of the thin metal wire 16 is connected to the lower surface of the inner portion of the signal connecting lead 12, the thin metal wire 16 can be reliably embedded in the sealing resin 17.

That is, it is possible to prevent the thin metal wires 16 from being exposed from the sealing resin 17 while making the resin-sealed semiconductor device thin.

Moreover, since the sealing resin 17 wraps around the inner side of the signal connecting lead 12, the holding force of the sealing resin 17 with respect to the signal connecting lead 12 also increases.

Further, by providing the groove portion 31 on the upper surface of the outer portion of the signal connecting lead 12, the holding force of the sealing resin 17 with respect to the signal connecting lead 12 is increased, and the outside of the signal connecting lead 12 is increased. By making the width of the upper part of the one part wider than that of the lower part, the holding force of the sealing resin 17 is further increased.

-Second Specific Example- FIG. 16 is a sectional view of a resin-sealed semiconductor device according to a second specific example. As shown in the figure, also in this example, the die pad 13 is provided only on the side portion of the semiconductor chip 15, and moreover, supports the semiconductor chip 15 from the main surface side, that is, the lower surface side of the semiconductor chip 15. In the present specific example, unlike the first specific example, the inner portion of the signal connecting lead 12 is half-etched from the lower surface side, and the inner portion is upset and upset. One end of the thin metal wire 16 is connected to the lower surface of the cut portion.

In this specific example, the inner portion of the signal connecting lead 12 can be brought closer to the semiconductor chip 15 as compared with the first specific example, so that the reliability of the thin metal wire 16 is improved. Further, since a sufficient space is secured below the inner portion of the signal connecting lead 12, the thin metal wire 12 can be reliably embedded in the sealing resin 17, and the thin metal wire 16 is exposed from the sealing resin 17. Can be prevented more reliably.

In this specific example as well, the bipad 1
The plane shape of 3 may be formed by four rectangular portions isolated from each other only near the corners of the side portions of the die pad as shown in FIG.
Alternatively, the die pad 13 may include two strip-shaped portions extending along two sides as shown in FIG. In addition, FIG.
The main surface side of the semiconductor chip 15 may be supported by the die pad 13 having a planar shape as shown in (a) and (b).

(Fifth Embodiment) Next, a resin-sealed semiconductor device according to a fifth embodiment of the structure of the suspension lead 14 will be described. The resin-encapsulated semiconductor device in this embodiment may have any structure in each embodiment, but is different only in the shape of the suspension lead. Therefore, in the present embodiment, the description of the other parts except the suspension lead and the die pad connected thereto is omitted.

FIG. 18 (a) is a plan view of the lead frame according to this embodiment, and FIG. 18 (b) is FIG. 18 (a).
FIG. 9 is a cross-sectional view of the lead frame taken along the line XVIIIb-XVIIIb shown in FIG. As shown in FIGS. 18A and 18B, the suspension lead 14 is provided between the signal connection lead 12 connected to the outer frame 46 and the die pad 13. That is, the die pad 13 is configured to be supported by the outer frame 46 via the suspension leads 14 and the signal connection leads 12. This suspension lead 14 has a suspension lead 1
A U-shaped bent portion 45 for exposing a part of the resin 4 from the sealing resin is provided. Further, the die pad 13 is upset so that the die pad 13 is higher than the outer frame 46. In this embodiment, the upset amount is about 40 to 80 μm. Further, in this embodiment, the inner side portion of the signal connecting lead 12 is half-etched from the back surface side, and the suspension lead 14 and the die pad 13 are half-etched and thinned as a whole. Further, two grooves that are orthogonal to the direction in which the signal connecting leads 12 extend are formed on the front side of the signal connecting leads 12.

As described above, by providing the suspension lead 14 between the signal connecting lead 12 and the side portion of the die pad 13, the suspension lead 14 can be shorter than the suspension lead 14 provided at the corner portion, and the suspension lead 14 has a high strength. Can be improved. Further, by supporting the die pad position by the bent portion, it is possible to further stabilize the die pad position. Therefore,
The function of suppressing the deformation of the die pad due to the flow of the sealing resin 17 in the resin sealing step can be further enhanced, and the deformation of the die pad due to the flow of the sealing resin or the like can be performed even when a large area die pad is required. Can be suppressed. In particular, in a thin resin-encapsulated semiconductor device, deformation of the die pad increases the risk of the die pad protruding from the encapsulation resin, but this specific example can effectively prevent such a problem. .

By providing such a bent portion 45 in a part of the suspension lead 14, it is possible to cut a part of the suspension lead 14 exposed by a laser or the like after the resin sealing step. The advantage is that the die pad 13 and the signal connecting lead 12 connected to the outside of the suspension lead 14 can be electrically separated. That is, by cutting a part of the suspension lead 14 after the resin sealing step, for example, the electrical connection between the signal connection lead 12 and the die pad 13 can be cut off, and also for the semiconductor chip on which the bipolar transistor is mounted. There is an advantage that such a structure can be applied.

Further, before the resin sealing step, the sealing tape is brought into close contact with the surface of the bent portion 45 to be exposed, and after the resin sealing step is completed, the sealing tape is still attached and the sealing tape is attached. A part of the bent portion 45 of the suspension lead 14 may be cut from above 21. By cutting a part of the suspension lead 14 in this manner, the above-described effects can be obtained in the resin-sealed semiconductor device to be formed. Moreover, the bent portion 4
Since the periphery of 5 is covered with the sealing tape, even if the melted material due to the laser scatters around, the scattered material can be easily removed from the resin-sealed semiconductor device by peeling off the sealing tape. is there.

(Sixth Embodiment) Next, a sixth embodiment will be described. In this embodiment, a structure for using the suspension lead as a reinforcing external terminal will be described.

FIG. 19 is a plan view showing the structure of the back surface of the resin-sealed semiconductor device according to the sixth embodiment.

As shown in the figure, in the resin-sealed semiconductor device of this embodiment, the external electrodes 18 connected to the signal connection leads are exposed on the back surface and the die pad 13 is supported at four corners. The outer end of the suspension lead 14 for exposing is exposed, and this portion functions as a reinforcing external terminal 49. That is, when the resin-sealed semiconductor device is mounted on the mounting substrate, the electrodes on the mounting substrate side and the external electrodes 1 of the resin-sealed semiconductor device are soldered or the like.
And 8 are connected. At that time, the mounting strength can be extremely increased by interposing solder or the like between the reinforcing external terminal 49 and the dummy terminal on the mounting substrate side.
Further, the presence of the reinforcing external terminal 49 makes the self-alignment action due to the tension of the solder remarkable, so that the time required for mounting can be shortened and the mounting position accuracy can be improved.

It goes without saying that the structure of each of the concrete examples and modified examples of the fifth embodiment can be applied to the suspension lead 14 functioning as an external terminal in this embodiment.

The reinforcing external terminal 49 and the external electrode 18
By changing the height position of and, it is possible to further improve the alignment property, and it is possible to shorten the time required for mounting and significantly improve the positional accuracy of mounting. In that case, the height difference between the lower surface of the exposed portion of the reinforcing external terminal 49 and the lower surface of the exposed portion of the external electrode 18 is preferably 10 to 150 μm.

The external electrodes 18 in the present invention are not necessarily provided on the four sides of the back surface of the resin-encapsulated semiconductor device, but are provided only along any two parallel sides. May be.

(Seventh Embodiment) In this embodiment, a resin sealing method for adjusting the protrusion amount of the external electrode from the sealing resin will be described.

FIG. 20 is a sectional view showing a resin encapsulation process in the manufacturing process of the resin-encapsulated semiconductor device according to this embodiment. As shown in the figure, the upper die 50a and the lower die 50
The semiconductor die 15 is mounted on the die pad 13 by using a sealing die composed of b, and the electrode pad of the semiconductor chip and the signal connecting lead 12 are connected by the fine metal wire 16 is a lower die of the sealing die. It is mounted on the mold 50b, and resin sealing is performed with the sealing tape 21 in close contact with the lower surface of the lead frame.

Here, the feature of the manufacturing method of the present embodiment is that
In the lower die 50b, the external electrode 18 (and the outer frame 4) which is an outer portion of the lead 12 for signal connection of the lead frame.
It is a point that a concave escape portion 52 is provided in a region facing 6).

By thus providing the escape portion 52 in the sealing die, the sealing tape 21 is allowed to escape toward the escape portion 52, so that the amount of the signal connecting lead 12 biting into the sealing tape 21. Becomes smaller. As a result, the amount of protrusion of the portion to be protruded can be adjusted to a desired value by not only the mold clamping force of the sealing mold but also the depth of the escape portion 52, and the amount of resin burr generated is also minimized. be able to.

Similarly, in each of the above-described embodiments, by providing a relief portion on the mold surface facing the exposed portion (for example, the bent portion), the amount of protrusion of the exposed portion from the sealing resin and the resin burr can be adjusted. Can be minimized.

However, in the case of adjusting the mold clamping force between the upper mold and the lower mold of the sealing mold and making the size of the lead frame larger than the size between the upper mold and the lower mold. The amount of protrusion of the exposed portion in each of the above-described embodiments may be adjusted according to the set amount of dimensions.

(Other Embodiments) By providing a hole for vacuuming in the die and performing resin sealing while vacuuming the sealing tape 21, generation of wrinkles in the sealing tape is suppressed, The back surface of the sealing resin can be flattened.

[0101]

According to the resin-sealed semiconductor equipment of the present invention, even when a die pad of a large area is required, a high thickness of the ability to prevent exposure of the sealing resin due to the deformation of the die pad It is possible to provide a resin-encapsulated semiconductor device that has been completed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a resin encapsulation type semiconductor device according to a first embodiment of the present invention through a sealing resin.

FIG. 2 is a cross-sectional view showing a step of preparing a lead frame in the manufacturing process of the resin-encapsulated semiconductor device of the first embodiment.

FIG. 3 is a cross-sectional view showing a step of joining a semiconductor chip to a die pad in the manufacturing process of the resin-encapsulated semiconductor device of the first embodiment.

FIG. 4 is a cross-sectional view showing a step of forming thin metal wires in the manufacturing process of the resin-encapsulated semiconductor device of the first embodiment.

FIG. 5 is a cross-sectional view showing a step of laying a sealing tape under a lead frame in the manufacturing process of the resin-sealed semiconductor device of the first embodiment.

FIG. 6 is a cross-sectional view showing a resin encapsulation process in the process of manufacturing the resin-encapsulated semiconductor device of the first embodiment.

FIG. 7 is a plan view and a sectional view of a lead frame according to a first example of the second embodiment of the present invention.

FIG. 8 is a plan view of a lead frame according to a modification of the first example of the second embodiment of the present invention.

FIG. 9 is a plan view and a cross-sectional view of a lead frame according to a second example of the second embodiment of the present invention.

FIG. 10 is a plan view of a lead frame according to a modification of the second specific example of the second embodiment of the present invention.

FIG. 11 is a sectional view of a resin-sealed semiconductor device according to a first example of the third embodiment of the present invention.

FIG. 12 is a sectional view of a resin-sealed semiconductor device according to a second specific example of the third embodiment of the present invention.

FIG. 13 is a sectional view of a resin-encapsulated semiconductor device according to a third example of the third embodiment of the present invention.

FIG. 14 is a sectional view of a resin-encapsulated semiconductor device according to a fourth example of the third embodiment of the present invention.

FIG. 15 is a cross-sectional view of a resin-sealed semiconductor device according to a first example of the fourth embodiment of the present invention.

FIG. 16 is a sectional view of a resin-sealed semiconductor device according to a second example of the fourth embodiment of the present invention.

FIG. 17 is a plan view showing a planar shape of a die pad of a resin-encapsulated semiconductor device according to first and second specific examples of a fourth embodiment of the present invention.

FIG. 18 is a plan view and a sectional view of a lead frame according to a fifth embodiment of the present invention.

FIG. 19 is a plan view showing the structure of the back surface of the resin-sealed semiconductor device according to the sixth embodiment of the present invention.

FIG. 20 is a cross-sectional view showing a resin-sealing step in a manufacturing process of a resin-sealed semiconductor device according to a seventh embodiment of the present invention.

FIG. 21 is a cross-sectional view of a conventional resin-sealed semiconductor device of a type having an external electrode on the back surface side.

[Explanation of symbols]

12 signal connection leads 13 die pad 14 Hanging lead 15 semiconductor chips 16 thin metal wires 17 Sealing resin 18 External electrode 21 sealing tape 30 openings 31 groove 45 Bend 46 Outer frame 49 External terminal for reinforcement 50a Upper mold 50b Lower mold 52 Runaway

Claims (7)

(57) [Claims] 1. A lower surface of the die pad having a die pad, a plurality of suspension leads for supporting the die pad, a signal connecting lead, an electrode pad on a main surface, and a main surface facing downward. A semiconductor chip having an area larger than that of the die pad, a connecting member for electrically connecting the electrode pad of the semiconductor chip and the signal connecting lead, the die pad, the semiconductor chip, the signal connecting lead And a sealing resin that seals the connection member, a part of the signal connecting lead is exposed on the back surface side of the sealing resin and functions as an external terminal, and the die pad is in the sealing resin. The die pad and the region of the suspension lead on which the semiconductor chip is mounted are thinly formed by half-etching and are the same as each other. Resin-sealed semiconductor device, characterized by having himself. 2. The resin-sealed semiconductor device according to claim 1, wherein the die pad and the region of the suspension lead on which the semiconductor chip is mounted are half-etched from the lower surface side. Sealed semiconductor device. 3. The resin-sealed semiconductor device according to claim 1, wherein each of the suspension leads is interposed between the die pad and the signal connection lead. Semiconductor device. 4. The resin-encapsulated semiconductor device according to claim 1, wherein each of the suspension leads is partially provided with a bent portion. 5. The resin-sealed semiconductor device according to claim 4, wherein each of the suspension leads is cut at the part. 6. The resin-sealed semiconductor device according to claim 5, wherein the vicinity of the cut portion of each suspension lead is thin. 7. A bottom surface of the die pad having a die pad, a plurality of suspension leads for supporting the die pad, signal connecting leads, and an electrode pad on the main surface, with the main surface facing downward. And a connecting member for electrically connecting the electrode pad of the semiconductor chip and the signal connecting lead, and a seal for sealing the die pad, the semiconductor chip, the signal connecting lead and the connecting member. A part of the signal connecting lead is exposed on the back surface side of the sealing resin and functions as an external terminal, and the die pad is embedded in the sealing resin. Part of the lead is exposed on the back surface side of the sealing resin, and this exposed part functions as a reinforcing external terminal, and the lower surface of the reinforcing external terminal in each of the suspension leads and the above The resin-encapsulated semiconductor device is characterized in that the height position is different from the lower surface of the external terminal in the signal connecting lead.