JP3535760B2 - Resin-sealed semiconductor device, method of manufacturing the same, and lead frame - 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 and a lead frame are encapsulated with an encapsulating resin, and in particular, a lower surface of a die pad for dissipating heat generated from a power element. Regarding the improvement of the exposed one.

[0002]

2. Description of the Related Art In recent years, in order to cope with miniaturization of electronic equipment, it is required to mount semiconductor parts mounted on the electronic equipment at a high density, and accordingly, the semiconductor chip and the lead frame are sealed with resin. 2. Description of the Related Art Semiconductor parts such as resin-sealed semiconductor devices that have been sealed by means of smaller and thinner semiconductor components are being advanced. As one type of resin-encapsulated semiconductor device that achieves such an object, the outer lead protruding laterally of the package is eliminated, and an external electrode for electrically connecting to the mother substrate is provided on the lower surface side. The so-called QFN (Quad Fla)
A tpack (Non-leaded package) type package is known.

Here, in particular, when a power element is built in a semiconductor chip, it is necessary to reduce the size and thickness while taking heat dissipation into consideration. Therefore, conventionally, as a QFN for a power element (hereinafter referred to as a power QFN), a lower surface exposed type structure in which a lower surface of a die pad on which a semiconductor chip is mounted is exposed without being covered with a sealing resin is adopted. Hereinafter, a structure and a manufacturing method of a conventional QFN for a power device will be described.

FIG. 17A is a perspective view of a conventional power QFN, and FIG. 17B is a XVIIb-XVIIb of FIG. 17A.
17C is a cross-sectional view taken along the line, and FIG. 17C is a back view of the conventional power QFN.

As shown in FIGS. 17A to 17C, a conventional power QFN is provided with a lead frame composed of a signal lead 101, a die pad 102, and a suspension lead 103 supporting the die pad 102. There is. A semiconductor chip 104 containing a power element is bonded onto the die pad 102 with an adhesive 108,
The electrode pads (not shown) of the semiconductor chip 104 and the signal leads 101 are electrically connected by the thin metal wires 105. Then, the portion of the die pad 102 excluding the lower surface, the semiconductor chip 104, the signal leads 101,
The suspension lead 103 and the thin metal wire 105 are sealed resin 10
It is sealed by 6. In this structure, the sealing resin 106 does not exist on the back surface side of the signal lead 101, the back surface side of the signal lead 101 is exposed, and the lower portion of the signal lead 101 including this exposed surface is the external electrode 101a. Has become.

The lower surface 102a of the die pad 102
Is not covered with the sealing resin 106 and is exposed and functions as a heat dissipation plate. By contacting the die pad 102 with the heat dissipation part of the mother substrate, the amount of heat emitted from the power element with high power consumption is externally exposed. It is released to suppress the temperature rise in the package.

Further, conventionally, when the power QFN is mounted on a mounting board such as a printed board, the sealing resin 106 necessary for joining the external electrode 101a, which is the lower portion of the signal lead 101, to the electrode of the mounting board. In order to secure the standoff height from the back surface, a ball electrode made of solder is provided on the external electrode 101a, and the standoff height is secured by the ball electrode and mounted on the mounting substrate.

Such a power QFN is formed by the following steps, for example. First, the signal lead 10
1. A lead frame having the die pad 102, the suspension leads 103, etc. is prepared. Incidentally, this lead frame is often provided with a dam bar for stopping the outflow of the sealing resin at the time of resin sealing. Next, the semiconductor chip 1 is placed on the die pad 102 of the prepared lead frame.
04 is joined by the adhesive 108. This process is a so-called die bonding process. Then, the die pad 102
The semiconductor chip 104 and the signal lead 10 joined together
1 and 1 are electrically connected by a thin metal wire 105. This process is a so-called wire bond process. Fine metal wire 1
For 05, an aluminum thin wire, a gold (Au) wire, or the like is appropriately used.

Next, the die pad 102 and the semiconductor chip 1
The part of the wire 04 except the lower surface, the signal lead 101, the suspension lead 103, and the thin metal wire 105 are sealed with a sealing resin 106 made of epoxy. In this case, the semiconductor chip 1
The lead frame to which 04 is bonded is housed in a sealing mold and is transfer-molded. Especially, in the state where the back surface of the signal lead 101 is in contact with the upper mold or the lower mold of the sealing mold. , Resin sealing is performed. Finally, the tip end of the signal lead 101 protruding outward from the sealing resin 106 after the resin sealing is cut. By this cutting process,
The tip surface of the signal lead 101 after cutting and the sealing resin 106
The sides of and are almost on the same plane. That is, it has a structure without an outer lead that has conventionally functioned as an external terminal, and a ball electrode made of solder is externally provided below the external electrode 101a exposed under the signal lead 101 without being covered with the sealing resin. It is formed as a terminal. Further, a solder plating layer may be formed instead of the solder ball.

[0010]

However, the above-mentioned conventional power QFN has the following problems. On the back surface of the semiconductor device, since the lower surface of the external electrode 101a and the surface of the sealing resin 106 are substantially on the same surface,
The standoff height from the sealing resin 106 cannot be obtained.
Therefore, a ball electrode made of solder or the like must be provided and mounted on the mounting substrate, which causes a problem that efficient mounting cannot be performed.

Further, in the resin encapsulation step of the conventional method for manufacturing a resin encapsulation type semiconductor device, the lead frame to which the semiconductor chip is joined is housed in the encapsulation die and the surface of the lower die is used for signal. Although the leads are pressed and brought into close contact with each other for resin encapsulation, the encapsulating resin still wraps around the back side of the signal leads, causing resin burrs (resin protrusion) on the surface of the external electrodes. There was also a defect.

Therefore, for example, in a resin sealing step, a sealing tape is interposed between the lower surface of the outer frame or the signal lead and the mold surface of the sealing mold, and the lower end portion of the signal lead is attached to the sealing tape. By encapsulating the resin with the
Some measures have been taken such that the lower ends of the signal leads are projected below the sealing resin. In that case, when the outer frame is deformed mainly by the mold clamping force applied to the outer frame and the signal leads adjacent to the outer frame, the deformation extends to the die pad through the suspension leads, causing deformation of the die pad and position change. There is. To avoid this problem,
It is possible to eliminate the suspension leads, but if the die pad cannot be reliably supported, reliability may be impaired.

In consideration of the above points, a bending absorption portion (a spring-like function) is provided by forming a bent portion in a part of the suspension lead and forming a rising portion which is higher than other portions. Therefore, it is preferable to avoid a defect such as deformation of the die pad due to the mold clamping force applied to the outer frame of the lead frame.

However, when the suspension lead is provided with a rising portion so as to have a deformation absorbing function, when a large-sized semiconductor chip is to be mounted, the semiconductor chip and the signal lead are not mounted regardless of the small-sized semiconductor chip. There was a problem that it interfered with the rising part, that is, it had poor adaptability to the chip size.

An object of the present invention is to provide a resin-sealed semiconductor device which can be applied over a wide range of semiconductor chip sizes, a method of manufacturing the same, and a lead frame suitable for the same.

[0016]

A lead frame of the present invention is a lead frame used for manufacturing a resin-sealed semiconductor device, and has an opening provided in a region where a semiconductor chip is to be mounted, An outer frame surrounding the opening,
A die pad for supporting a semiconductor chip arranged in the opening, a plurality of suspension leads for supporting the die pad, and a plurality of signals connected to the outer frame at the edge of the opening and extending toward the die pad. For each of the suspension leads, a rising portion that is higher than the other portions is formed, and the central portion of the die pad is upset from the peripheral portion thereof, and the semiconductor chip is It functions as a chip support part for supporting, and the rising part of the suspension lead is
The height of the pad decreases from the part near the pad to the outside.
It is inclined to become .

Thus, since the suspension lead is provided with the rising portion, the suspension lead has a deformation absorbing function, and this lead frame is used to project the lower portion of the signal lead from the sealing resin. It is possible to prevent the position of the die pad from being changed or deformed due to the deformation of the suspension lead due to the mold clamping force applied to the outer frame of the lead frame when the resin sealing is performed using the sealing tape. Further, since the central portion of the die pad is upset from the peripheral portion thereof, even if the size of the semiconductor chip is large, interference between the semiconductor chip and the suspension leads does not occur. That is, it is possible to improve the selectivity of the size of the semiconductor chip that can be mounted on the lead frame. In addition, since the semiconductor chip is mounted only in the central portion of the die pad, the sealing resin is also present between the peripheral portion of the die pad and the semiconductor chip. As a result, the semiconductor chip is securely held by the sealing resin and is resistant to moisture. Thus, it becomes possible to form a resin-encapsulated semiconductor device having a high price.

In the lead frame, the central portion of the die pad is upset from the peripheral portion by the semi-cut portion, so that a state in which the central portion is upset can be realized with almost no distortion of the die pad. .

In the lead frame, the upper surface of the central portion of the die pad is located above the uppermost surface of the rising portion of the suspension lead, so that the semiconductor chip after mounting the semiconductor chip can easily interfere with the suspension lead. It can be avoided without fail.

In the lead frame, a punched portion is provided between the central portion and the peripheral portion of the die pad, so that when the lead frame is used for resin sealing, the sealing resin is applied to the central portion. Can be made to flow into the lower part of the die pad, and it can be used for forming a resin-sealed semiconductor device in which the central portion of the die pad and the sealing resin have high adhesion.

The first resin-encapsulated semiconductor device of the present invention is
A semiconductor chip, a die pad that supports the semiconductor chip, an adhesive member that adheres the semiconductor chip onto the die pad, a plurality of suspension leads for supporting the die pad, and a plurality of extending extending toward the die pad. A signal lead, a connecting member for electrically connecting the semiconductor chip and the signal lead to each other, and a sealing resin for sealing the semiconductor chip, die pad, adhesive member, connecting member, suspension lead and signal lead. And a part of the signal lead protrudes below the lower surface of the encapsulating resin and functions as an external terminal. The upper part of the die pad is formed higher than that of the semiconductor chip, and the central part of the die pad is upset from its peripheral part. Flop, have been mounted on the central part
The bottom surface of the semiconductor chip is the top of the suspension lead.
It is located above the plane .

As a result, due to the above-mentioned effects, it is possible to improve the selectivity and the moisture resistance of the semiconductor chip in the resin-sealed semiconductor device.

In the first resin-encapsulated semiconductor device, it is preferable that the lower surface of the semiconductor chip is located above the uppermost surface of the suspension lead.

In the first resin-encapsulated semiconductor device, the rising portion of the suspension lead can be inclined such that the height position thereof becomes lower from the portion near the die pad toward the outside.

In the first resin-encapsulated semiconductor device, a punched portion is provided between the central portion and the peripheral portion of the die pad, and the encapsulating resin is embedded below the central portion of the die pad. By setting it, the adhesiveness between the central portion of the die pad and the sealing resin can be further enhanced.

In the first resin-encapsulated semiconductor device, a closed-loop groove is formed on the lower surface of the peripheral portion of the die pad, so that the resin-encapsulated semiconductor without encapsulation of the encapsulating resin on the lower surface of the peripheral portion. The device can be obtained.

[0027]

[0028]

[0029]

The method of manufacturing a resin-encapsulated semiconductor device of the present invention comprises a step (a) of preparing a semiconductor chip, an opening provided in a region where the semiconductor chip is to be mounted, and an outer portion surrounding the opening. A frame, a die pad for supporting the semiconductor chip arranged in the opening, a plurality of suspension leads for supporting the die pad, and a plurality of extending to the die pad connected to the outer frame at the edge of the opening. Prepare a lead frame that has a signal lead, a part of each suspension lead is a rising part higher than other parts, and the center part of the die pad is upset from its peripheral part. Step (b), step (c) of fixing the semiconductor chip on the central portion of the die pad of the lead frame, and the connecting member The body tip and the signal leads and each other step of electrically connecting (d), is interposed a sealing tape between the back and the sealing die of the lead frame,
With the mold clamping force applied to the lead frame and the sealing tape, the semiconductor chip, the die pad, the connecting member,
And a step (e) of sealing the suspension lead and the signal lead with a sealing resin.

With this method, the lower portion of the signal lead projects from the sealing resin while relaxing the size limitation of the semiconductor chip as described above and preventing the die pad from being deformed or moved in the resin sealing step. The obtained structure can be obtained.

In the method of manufacturing a resin-sealed semiconductor device, in the step (e), a mold clamping force is applied to the outer frame of the lead frame and the sealing tape so that the lead frame is adjacent to the outer frame. The amount of protrusion of the lower portion of the signal lead from the sealing resin can be increased.

In the method of manufacturing a resin-sealed semiconductor device described above, in the step (a), a closed loop groove is formed in the lower surface of the peripheral portion of the die pad to seal the lower surface of the peripheral portion of the die pad. It is possible to reliably prevent the resin from getting around.

In the method of manufacturing a resin-sealed semiconductor device, in the step (a), a punched portion is formed between the central portion and the peripheral portion of the die pad,
In the resin sealing step, the sealing resin can be embedded below the center of the die pad.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) In the following embodiments, a structure in which the present invention is applied to a power QFN incorporating a power element as a resin-sealed semiconductor device will be described as an example.

—Structure of Power QFN— FIG. 1A shows the power Q according to the first embodiment of the present invention.
It is sectional drawing which expands and shows the structure of FN, Comprising: FIG.
It is sectional drawing in the Ia-Ia line shown in FIG. Also, FIG.
(B) is a plan view of the power QFN of the present embodiment.
However, in FIG. 1A, the dimension enlargement ratio in the vertical direction of the cross section is set higher than the dimension enlargement ratio in the horizontal direction in order to facilitate understanding of the structure. In addition, FIG.
In the above, the sealing resin 6 is treated as a transparent body.

FIG. 2 is a rear view of the power QFN according to the present embodiment. In FIG. 2, the sealing resin is treated as an opaque body.

As shown in FIGS. 1 (a), 1 (b) and 2, the power QFN of this embodiment includes the following members separated from the lead frame. That is, a signal lead 1 for transmitting an electric signal including a power source and ground,
A die pad 2 for mounting the semiconductor chip 4 and a suspension lead 3 for supporting the die pad 2 are provided.

Here, the feature of this embodiment is that the central portion 2a is upset more than the peripheral portion 2b by the circular semi-cut portion 11 in the die pad 2, and the hanging lead 3 has two bent portions. That is, the suspension leads 3 are provided with the deformation absorbing function. The semiconductor chip 4 is bonded onto the central portion 2a of the die pad 2 with a DB (die bond) paste 7, and the electrode pad (not shown) of the semiconductor chip 4 and the signal lead 1 are connected by a thin metal wire 5. Electrically connected to each other.

The circular semi-cutting portion 11 stops the punching process by a press on the metal plate forming the die pad 2, and the circular portion is connected to the metal plate in a semi-cutting state before punching in a circular shape. It is the part that is being done. The half-cut portion 11 has a structure in which a circular half-cut portion is broken by the pressing force in the protruding direction.

Instead of the semi-cut portion 11 of the die pad 2, it is possible to upset the central portion 2a from the peripheral portion by half etching.

Then, the signal leads 1, the die pad 2,
The suspension lead 3, the semiconductor chip 4, and the thin metal wire 5 are sealed in a sealing resin 6. However, the lower part of the signal lead 1 and the lower part of the outer end of the suspension lead 3 are sealed with the resin 6
Projects downward from the lower surface of the. This signal lead 1
The lower part of the electrode functions as an external electrode 9 (external terminal) for electrically connecting to the mother substrate. Further, on the lower surface of the external electrode 9, there is no protruding portion (resin burr) of the sealing resin in the resin sealing step. Such a structure of the external electrode 9 having no resin burr and protruding downward can be easily realized by a manufacturing method described later.

On the other hand, the lower surface of the peripheral portion 2b of the die pad 2 is in a substantially common plane with the lower surface of the sealing resin 6 and is exposed without being covered with the sealing resin 6. as a result,
The lower surface of the peripheral portion 2b of the die pad 2 is located above the lower surfaces of the outer end portions of the signal lead 1 and the suspension lead 3, and the suspension lead 3 becomes lower in height toward the outside. Is so inclined. Further, on the lower surface of the peripheral portion 2b of the die pad 2, there is formed a fine groove 12 having a substantially square planar shape in which only one corner portion is chamfered for displaying the first pin.

The function, function and effect of the structure of the power QFN of this embodiment will be described below.

First, there is no outer lead on the side of the signal lead 1, and the lower part of the signal lead 1 is the outer electrode 9.
Therefore, the size of the power QFN can be reduced while maintaining the size of the semiconductor chip. Moreover, since there is no resin burr on the lower surface of the external electrode 9, the reliability of bonding with the electrode on the mounting substrate side is improved. In addition, since the external electrode 9 is formed so as to project from the lower surface of the sealing resin 6, the external electrode is used when the external electrode and the electrode of the mounting substrate are joined when the resin-sealed semiconductor device is mounted on the mounting substrate. The standoff height of 9 is secured in advance. Therefore, the external electrode 9 can be used as it is as an external terminal, and it is not necessary to attach a solder ball to the external electrode 9 for mounting on a mounting board as in the conventional case, which is advantageous in terms of manufacturing steps and manufacturing cost. Become. As will be described later, the effect of preventing the formation of resin burrs becomes more prominent by providing the thin groove 12.

Since the intermediate portion (the rising portion) of the suspension lead 3 has a sectional shape which is lifted upward by the two bent portions 13 and 14, the suspension lead 3
Has a deformation absorbing function, and is used for the outer frame of the lead frame when resin sealing is performed using a sealing tape to project the lower portion of the signal lead 1, that is, the external electrode 9 from the sealing resin 6. It is possible to prevent the position of the die pad 2 from being changed or deformed due to the deformation of the suspension lead 3 caused by the applied mold clamping force.

Further, since the central portion 2a of the die pad 2 is lifted up by the semi-cut portion 11, the size of the semiconductor chip 4 is so large that the semiconductor chip 4 protrudes outside the bent portion 13 of the suspension lead 3. Even if
It is possible to position the lower surface of the semiconductor chip 4 mounted on the central portion 2a above the uppermost surface of the suspension lead 3, which may cause interference between the semiconductor chip 4 and the rising portion of the suspension lead 3. Absent. In other words, it is possible to improve the size selectivity of the semiconductor chip 4 while providing a rising portion on a part of the suspension lead 3 to have a deformation absorbing function.

Further, as a result, the entire lower surface of the semiconductor chip 4 is not in contact with the die pad 2 but only with the central portion 2a of the die pad 2, so that the moisture resistance is improved. The reason will be described below. FIG. 17
In the case of the conventional structure shown in (a) to (c), since the semiconductor chip and the die pad are in a so-called solid state when the size of the semiconductor chip is small,
If moisture or water enters between the die pad 2 and the sealing resin 6, the adhesion between the semiconductor chip and the die pad may be deteriorated, or the moisture resistance may be deteriorated such as cracks. On the other hand, as in the present embodiment, the semiconductor chip 4 and the die pad 2 are the central portion 2a of the die pad 2.
If the size of the semiconductor chip 4 is as small as the die pad 2, the die pad 2
The sealing resin 6 also exists between the peripheral portion 2b and the semiconductor chip 4. As a result, even the small-sized semiconductor chip 4 is reliably held by the sealing resin 6,
Since moisture and water can be prevented from entering from the back side, the package will not be cracked.

In the state shown in FIG. 1A, it seems that the semiconductor chip 4 and a part of the suspension lead 3 are in contact with each other, but even if the semiconductor chip 4 and the suspension lead 3 are in contact with each other. Good or not in contact. Further, the upper surface of the central portion 2a when the die pad 2 is upset may be formed so as to be located above the uppermost surface of the suspension lead 3, or the central portion 2a when the die pad 2 is upset. Is located below the uppermost surface of the suspension lead 3, but considering the thickness of the DB paste 7, the lower surface of the semiconductor chip 4 is located above the uppermost surface of the suspension lead 3. Good. When the semiconductor chip 4 and a part of the suspension lead 3 are in contact with each other, there is an advantage that the stability of supporting the semiconductor chip 4 is improved.

Further, as shown in FIG. 1A, according to the power QFN of this embodiment, even if the semiconductor chip 4 overlaps the signal lead 1 above the signal lead 1, the semiconductor chip 4 does not overlap. Since the signal lead 1 does not interfere with the signal lead 1, there is an advantage that the inner length of the signal lead 1 can be made sufficiently large and the adhesion between the signal lead 1 and the sealing resin 6 can be enhanced.

-Description of Manufacturing Method- Next, the manufacturing method of the power QFN of this embodiment will be described.
A description will be given with reference to the drawings. 3 to 8 are cross-sectional views showing the manufacturing process of the power QFN according to this embodiment.

First, in a step shown in FIG. 3A, a copper alloy plate is patterned by etching to form a lead frame 20 having a large number of openings 22 for mounting semiconductor chips. In FIG. 3A, only one opening is shown for easy viewing. The lead frame 20 includes a signal lead 1 extending from the outer frame 21 toward the inside of the opening 22, a die pad 2 for mounting a semiconductor chip, and the die pad 2 and the outer frame 21 connected to each other. And a suspension lead 3 for supporting the. The lead frame 20 is not provided with a tie bar that prevents the sealing resin from flowing out during resin sealing.

In this state, a metal plating layer of nickel (Ni), palladium (Pd), gold (Au) or the like may be formed on the lead frame 20, and the following FIG.
You may form a metal plating layer after the process shown in FIG.

Next, in the step shown in FIG. 3B, press working is performed to form a semi-cut portion 11 that divides the die pad 2 of the lead frame 20 into a central portion 2a and a peripheral portion 2b. 4A and 4B are cross-sectional views showing the procedure of this press working. First, a punching die including a die 31 having a circular opening and a punch 32 having a circular planar shape that substantially matches the opening is prepared. Then, as shown in FIG. 4A, the die pad 2 of the lead frame 20 is placed on the punch 32, and the die 31 is brought into contact with the upper surface of the die pad 2 from above. Next, as shown in FIG. 4B, the die 31 is lowered.
At this time, the die 31 and the punch 32 bite into the die pad 2 from both sides thereof, but when the thickness a of the sheared portion and the thickness b of the unsheared portion become substantially the same value,
The descending amount of the die 31 is set in advance so that the descending of the die 31 is stopped. That is, while using the punching die, the central portion 2a of the die pad 2 is not punched but left in a semi-cut state. As a result, the central portion 2a that is upset from the peripheral portion 2b is formed.

By performing the semi-cutting process, the central part 2a of the die pad 2 which is a wide range can be upset without causing distortion in each part of the die pad 2 as compared with the general bending process. There is an advantage that can be.

Next, press working for forming the bent portions 13 and 14 of the suspension lead 3 and the peripheral portion 2b of the die pad are performed.
The press working for forming the narrow groove 12 on the lower surface of the is performed sequentially or simultaneously.

In FIG. 5 to FIG. 8 below, FIG.
7 shows a change in structure of a cross section corresponding to the cross section taken along line Ia-Ia shown in FIG. Further, in each figure, the enlargement ratio in the vertical direction is made larger than the enlargement ratio in the horizontal direction.

In the step shown in FIG. 5, the semiconductor chip 4 is placed on the central portion 2a of the die pad 2 of the prepared lead frame, and the two are mutually separated by the DB paste 7 made of silver paste using epoxy resin as a binder. To join.
This process is a so-called die bonding process.

Next, in the step shown in FIG. 6, the semiconductor chip 4 is
The electrode pad (not shown) and the signal lead 1 are electrically connected by the thin metal wire 5. This process is a so-called wire bond process. As the metal thin wire 5, an aluminum thin wire, a gold (Au) wire, or the like can be appropriately selected and used. Further, the electrical connection between the semiconductor chip 4 and the signal lead 1 may be made by a bump or the like instead of the metal thin wire 5.

Next, in the step shown in FIG. 7, the semiconductor chip 1
The sealing tape 15 is interposed between the lead frame 20 and the back surface of the signal lead 1 in a state where the lead frame 20 to which 5 is bonded and the sealing tape 15 is attached is attached to the sealing mold. . At this time, the sealing tape 15 is supplied by a roll as described later. Further, in the present embodiment, the lead frame is set upside down in the state shown in FIG. 7 and set in the sealing mold, but it may be set up in the state shown in FIG. 7. In the state shown in FIG. 7, the mold clamping force has not yet acted.

The sealing tape 15 serves to act as a mask for preventing the sealing resin from getting around the back surface of the signal lead 1 in the resin sealing process. The presence of the tape 15 can prevent the resin burr from being formed on the back surface of the signal lead 1. The sealing tape 15 is a tape based on a resin containing polyethylene terephthalate, polyimide, polycarbonate or the like as a main component, and can be easily peeled off after the resin sealing and is resistant to a high temperature environment at the time of resin sealing. If there is Here, a tape containing polyethylene terephthalate as a main component was used, and the thickness was 50 [μm].

Here, the sealing tape 15 is
The outer frame 21 of the lead frame 20, the signal leads 1, the portions other than the rising portions of the suspension leads 3, and the lower surfaces of the peripheral portion 2b of the die pad 2 are in close contact with each other.

Next, in the step shown in FIG. 8, the sealing resin 6 made of epoxy resin is poured into the sealing mold to perform resin sealing. At this time, the mold sealing force of the mold is applied to the outer frame of the lead frame 20 and the sealing tape 15 so that the sealing resin 6 does not wrap around the back surface of the signal lead 1. That is, the surface of the sealing tape 15 on the back surface side of the signal lead 1 adjacent to the outer frame is pressed against the mold surface to perform resin sealing. Therefore, since the die clamping force is not directly applied to the die pad 2, the die pad 2 is lifted upward and the suspension lead 3 is inclined so that the height position becomes lower toward the outside.

Finally, when the sealing tape 15 attached to the back surface of the signal lead 1 is removed by peeling off, the external electrode 9 protruding from the back surface of the sealing resin 6 is formed.
Then, the tip portion of the signal lead 1 is separated so that the tip surface of the signal lead 1 and the side surface of the sealing resin 6 are substantially flush with each other, so that the power QFN as shown in FIG. Is completed.

According to the manufacturing method of the present embodiment, since the sealing tape 15 is previously interposed between the back surface of the signal lead 1 and the sealing die before the resin sealing step, the sealing resin 6 Does not go around to the lower surface of the signal lead 1, and there is no resin burr on the back surface of the signal lead 1 that serves as an external electrode. Therefore, it is not necessary to remove the resin burr formed on the signal lead 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 lead is exposed. That is, by eliminating the troublesome process for removing the resin burr, the process in the mass production process of the resin-sealed semiconductor device (power QFN) can be simplified. Further, the peeling of the metal plating layer of nickel (Ni), palladium (Pd), gold (Au) or the like of the lead frame, which may occur in the conventional resin burr removal process using a water jet, can be eliminated. Therefore, it is possible to pre-plat each metal layer before the resin sealing step.

In addition, since the external electrode 9 formed by the above manufacturing method projects downward from the lower surface of the encapsulating resin 6, the external electrode 9 can be used as it is without attaching solder balls as in the conventional case. It can be used as an external terminal.

As shown in FIG. 8, in the resin sealing step, the sealing tape 15 is softened and thermally contracted by the heat of the molten sealing resin 6, so that the signal lead 1 is sealed. The tape 15 bites largely, and a step is formed between the back surface of the signal lead 1 and the back surface of the sealing resin 6. Therefore, the back surface of the signal lead 1 is covered with the sealing resin 6
Since it has a structure projecting from the back surface, the standoff height of the external electrode 9 below the signal lead 1 can be secured. Therefore, this protruding external electrode 9 can be used as it is as an external terminal.

Further, the back surface of the signal lead 1 and the sealing resin 6
The size of the step between the back surface and the back surface can be controlled by the thickness of the sealing tape 15 attached before the sealing step. In the present invention, since the sealing tape 15 having a thickness of 50 [μm] is used, the size of the step, that is, the protruding amount of the external electrode 9 is generally about half that, and the maximum is 50 [μm]. That is, since the amount of the sealing tape 15 entering above the back surface of the signal lead 1 is determined by the thickness of the sealing tape 15, the amount of protrusion of the external electrode 9 can be adjusted.
The thickness can be self-controlled to facilitate manufacturing. In order to control the protrusion amount of the external electrode 9, it is only necessary to control the thickness of the sealing tape 15 in the mass production process, and it is not necessary to provide another process. This is an extremely advantageous method. Regarding the sealing tape 15 to be interposed, the hardness, thickness, and material of the material are adjusted according to the desired size of the step.
And thermal softness can be determined.

Further, since the narrow groove 12 is provided on the lower surface of the peripheral portion 2b of the die pad 2, the peripheral portion 2 of the die pad is formed by the injection pressure of the sealing resin 6 melted at the time of resin sealing.
Since b is pressed downward and the sealing tape 15 is caught in the edge portion of the narrow groove 12, the wraparound of the sealing resin 6 is more effectively prevented.

-Details of Resin Sealing Step- Next, details of the resin sealing step in this embodiment will be described.

FIG. 9A is a plan view of a sealing die (lower die) used in this embodiment, and FIG. 9B is a resin encapsulation on the center line of FIG. 9A. It is a cross-sectional view showing the state of. 10 (a) to 10 (c) are perspective views for schematically explaining a resin sealing device provided with a sealing tape supplying device and a resin sealing procedure in the present embodiment. FIG. 11 is a cross-sectional view showing a state inside the sealing die during resin sealing.

As shown in FIGS. 9A and 9B, the sealing mold 51 used in this embodiment is the upper mold 51a and the lower mold 1.
It consists of 5b. And the upper die 51a has 4
There are provided vacuum suction holes 53 and vacuum suction grooves 52 for communicating the respective vacuum suction holes 53. Further, as shown in FIG. 10A, the lower mold 51b of the sealing mold 51 is formed.
Includes two semiconductor product molding parts 60 (lead frame 2
(A portion in which a number of die cavities corresponding to the number of semiconductor chips 4 mounted on 0 are formed) and a sealing resin flow path 6 for supplying a sealing resin to each semiconductor product molding portion 60.
1 and are provided.

9 (a) and 9 (b), only the structure and set state in one die cavity are shown for the sake of clarity, but the same structure and set state in other die cavities are also shown. ing. First, the state of resin sealing in one die cavity will be described with reference to FIG.

First, the lead frame 20 is set on the lower mold 51b so that each semiconductor chip 4 is housed in each die cavity of the lower mold 51b. At this time, the lower surface of the upper mold 51a and the upper surface of the sealing tape 15 are in contact with each other. Then, while pressing the upper mold 51a, the upper mold 51 is evacuated by a vacuuming device (not shown).
The sealing tape 15 is evacuated in four directions in the sealing die through the four vacuum suction holes 53 formed in a to maintain the state of being uniformly extended. By performing the resin sealing step in this state, the sealing tape 1 due to heat shrinkage at the time of resin sealing
It is possible to prevent wrinkles of No. 5 from occurring. As a result, the back surface of the resin of the resin-encapsulated semiconductor device is formed flat.

The mechanism of eliminating the above-mentioned wrinkles of the sealing tape will be described in more detail below. At the time of resin sealing, the sealing tape 15 undergoes heat shrinkage, and the vacuum tape 53 is evacuated against the shrinking action, so that the sealing tape 15 is pulled in the direction of each vacuum vacuum hole 53. To be In this way, by giving the stretched state to the sealing tape 15, the shrinkage of the sealing tape 15 is suppressed and the occurrence of wrinkles is prevented. Therefore, the sealing tape 15 is formed on the back surface of the formed resin-sealed semiconductor device.
The surface of the sealing resin 6 that was in contact with is flat.

It is desirable that the vacuum drawing groove 52 connected to the vacuum drawing hole 53 of the upper mold 51a be formed in depth and width in consideration of the elongation rate of the sealing tape 15.

However, it is also possible to pull the sealing tape individually from each vacuum drawing hole without providing the vacuum drawing groove.
The effect of preventing wrinkles from being generated on the sealing tape can be exerted.

The shape and number of the vacuum suction grooves are shown in FIG. 9 (a).
It is not limited to the shape and the number shown in. For example, it is possible to provide a plurality of rows of vacuum suction grooves.

In addition to the structure shown in FIG. 9B, an engraved portion is provided in a region located above the signal lead 1 on the upper surface of the upper die 51a to seal the resin when sealing. By escaping a part of the stop tape 15 into the engraved portion, a deep groove that is likely to be formed between the signal leads 1 may be suppressed shallowly.

Further, the method of preventing the sealing tape 15 from wrinkling is not limited to the method of providing the vacuum drawing groove, and the concave and convex portions engaging with each other are formed in the upper mold and the lower mold. It is also possible to apply tension to the sealing tape by forming the respective parts and engaging the concave part and the convex part when the mold clamping force is applied between the upper mold and the lower mold. Further, it is possible to provide a clamper on the sealing die and apply tension to the sealing tape by the clamper.

Next, the method for supplying the sealing tape 15 and the procedure for the overall resin sealing will be described with reference to FIGS.
11 and FIG. 11 will be described.

As shown in FIG. 10A, in the resin sealing device of this embodiment, the sealing tape is continuously applied while applying a constant tension between the unwinding roll 56a and the winding roll 56b. A sealing tape supply device configured to be able to unwind and wind up 152 is additionally provided.

Then, as shown in FIG. 10B, when the lead frame 20 on which a large number of semiconductor chips are mounted is set in the lower mold 51b, the resin tablet 62 becomes the sealing resin supply portion of the lower mold 51b. Be thrown into.

Next, as shown in FIG. 11, a sealing mold 51 is used.
The upper mold 51a and the lower mold 51b are clamped, and the sealing resin melted from below by the piston 58 is supplied to each semiconductor product molding unit 60, and the resin-sealed semiconductor device 55 is provided for each die cavity. (Power QFN) is injection molded. Then, when the injection molding is completed, the lower mold 51b is opened.

At this time, at the same time when the lower die 51b is opened, the sealing tape 15 is separated from the resin cull 63 and the resin-sealed semiconductor device 55 shown in FIG. Further, of the sealing tape 15, the portion used in this resin sealing step is wound up by the winding roll 56b, and the portion used in the next resin sealing step is supplied from the unwinding roll 56a. In the meantime, the resin cull 63 and the resin-sealed semiconductor device 5
5 is taken out from the lower mold 51b.

According to this embodiment, the unwinding roll 56
By continuously supplying the sealing tape 15 between "a" and the winding roll 56b, the resin sealing process using the sealing tape can be performed quickly, and the production efficiency can be improved. it can. Further, by applying a rotational force to the unwinding roll 56a and the winding roll 56b,
Appropriate tension can be applied to the sealing tape 15, and wrinkling of the sealing tape 15 in the resin sealing step can be more effectively suppressed.

In the present embodiment, the sealing tape 15 is supplied to the sealing die to be brought into close contact with the lead frame 20 with the lead frame 20 mounted on the die. Instead of the simple roll supply method, the sealing tape 15 may be attached to the lower surface of the signal lead 1 of the lead frame in advance before the resin sealing step.

(Second Embodiment) Next, a second embodiment of the present invention will be described. In the above-described first embodiment, as shown in FIG. 2, in the structure in which the central portion (chip supporting portion) of the die pad 2 is upset, the central portion 2
The encapsulating resin 6 does not exist below a and is simply a concave portion. However, in the present embodiment, the encapsulating resin is also filled under the central portion (chip supporting portion) of the die pad. To do.

FIGS. 12A and 12B are a plan view of a lead frame for forming the power QFN of this embodiment and a back view of the power QFN after resin sealing.

As shown in FIG. 12A, the die pad 2
The portion except the peripheral portion 2b of the above is a square-shaped central portion 2a that is upset, four connecting portions 2c that connect the central portion 2a and the peripheral portion 2b to each other, and the punched-out punched portion 2
and d. The central portion 2a is upset from the peripheral portion 2b by forming the bent portions 35 and 36 at two places of the connecting portion 2c.

However, the central portion 2a may be upset by performing the same semi-cutting processing as in the first embodiment at one place of the connecting portion 2c.

Further, in the first embodiment, only one thin groove 12 is formed on the lower surface of the peripheral portion 2b of the die pad 2, but in the present embodiment, a closed loop is formed on the lower surface of the peripheral portion 2b. A plurality of fine grooves 12a and 12b are provided. This is because the sealing resin may come around not only from the outer side of the peripheral portion 2b of the die pad 2 but also from the inner side.

Although the description of the manufacturing process in this embodiment is omitted, the sealing tape in the resin sealing process as well as the die bonding process for mounting the semiconductor chip on the die pad and the wire bonding process for forming the thin metal wires. Basically, the manufacturing method according to the first embodiment described above, such as a method for interposing the sealing tape between the lead frame and the sealing die, and supplying the sealing tape with a roll for eliminating wrinkles of the sealing tape. The process can be applied almost as it is.

As shown in FIG. 12 (b), the lead frame of this embodiment was used and the result of resin sealing with a sealing tape interposed between the lower surface of the peripheral portion 2b and the sealing mold. On the back surface of the obtained power QFN, the die pad 2
The sealing resin 6 also wraps around the lower part of the central portion 2a.

According to the power QFN of this embodiment, by providing such a punched portion 2d, the sealing resin 6 is passed from the periphery of the die pad 2 through the punched portion 2d to the lower portion of the central portion 2a in the resin sealing step. It will flow.
Therefore, since the sealing resin 6 can be embedded below the central portion 2a of the die pad 2, the adhesion between the sealing resin 6 and the die pad 2 is improved, and the reliability of the entire power QFN including the improvement of the moisture resistance is improved. It is possible to improve the sex.

(Third Embodiment) Next, a resin-sealed semiconductor device (power QFN) according to a third embodiment of the present invention.
Will be described. 13A to 13C are respectively a plan view of a lead frame used in the power QFN of this embodiment, a cross-sectional view taken along line XIIIb-XIIIb, and XIIIc-XII.
It is sectional drawing in the Ic line. FIG. 14 is a perspective view of the lead frame of this embodiment.

As shown in FIGS. 13A to 13C and FIG. 14, the die pad 40 of the lead frame of the present embodiment.
Is a square central portion 41 (chip supporting portion), circular corner portions 42 provided at the four corner portions, four side portions 43 directly connected to the corner portions 42, and the central portion 41.
Is divided into four connecting portions 44 that are connected to each side portion 43 and four punched portions 45 that are punched out.
The central portion 41, the side portion 43, and the connecting portion 44 are upset from the four corner portions 42. The suspension lead 3 is similar to the lead frame structure in the first embodiment in that the suspension lead 3 has a cross-sectional shape that is raised by the two bending portions 13 and 14 on the way.

Although the description of the manufacturing process in the present embodiment is omitted, the sealing tape in the resin sealing process as well as the die bonding process for mounting the semiconductor chip on the die pad, the wire bonding process for forming the thin metal wires, and the like. Basically, the manufacturing method according to the first embodiment described above, such as a method for interposing the sealing tape between the lead frame and the sealing die, and supplying the sealing tape with a roll for eliminating wrinkles of the sealing tape. The process can be applied almost as it is.

In this embodiment, since the area of the corner portion 42 in contact with the sealing tape is small, the first and second corners are not formed.
Even if the thin groove is not provided as in the embodiment, it is possible to reliably prevent the sealing resin from getting around to the lower surface of the corner portion 42.

FIG. 15 shows the back surface of the power QFN obtained as a result of resin sealing using the lead frame of this embodiment with a sealing tape interposed between the lower surface of the corner portion 42 and the sealing die. It is a figure. As shown in the figure, on the back surface of the power QFN according to the present embodiment, only the external electrode 9, the outer side end portion of the suspension lead 3 and the corner portion 42 of the die pad 40 are covered with the sealing resin 6. It is exposed without. That is, the sealing resin 6 is also embedded under the central portion 41 of the die pad 40. Further, in the manufacturing process of the power QFN of the present embodiment, the semiconductor chip is supported only by the central portion 41 of the die pad in the die bonding process of mounting the semiconductor chip on the die pad. That is, the punching portion 45 prevents the DB paste from spreading. The semiconductor chip is strongly held by the sealing resin existing below the punched portion 45. Since the contact area between the die pad 40 and the semiconductor chip is small as described above, it is possible to suppress deterioration of the moisture resistance of the resin-sealed semiconductor device as described above.

According to the power QFN of the present embodiment, the punching portion 45 is provided in a part of the die pad 40, so that the sealing resin 6 passes through the punching portion 45 and the central portion 41 (chip supporting portion) at the time of resin sealing. Since it flows downward, the sealing resin can be embedded under the central portion 41, and the same effect as that of the second embodiment can be exhibited.

(Fourth Embodiment) Next, a resin-sealed semiconductor device (power QFN) according to a fourth embodiment of the present invention.
Will be described. FIG. 16 shows the power QF of this embodiment.
It is a cross-sectional view of N and shows a shape in a cross-section corresponding to the line Ia-Ia in FIG.

In the lead frame used for the power QFN of this embodiment, the die pad 2 is not formed with a half-cut portion, and the die pad 2 is entirely formed flat. Therefore, there is no upset portion in the die pad 2. The suspension lead 3 is provided with two bent portions 13 and 14, and the middle portion of the suspension lead 3 is a rising portion that is higher than the end portion.
The semiconductor chip 4 is supported by the suspension leads 3 at the rising portion of the suspension leads 3. Also, the semiconductor chip 4 and the die pad 2 are fixed to each other by providing a thick DB paste 7 for joining the semiconductor chip 4 and the die pad 2. The structure of other parts is the same as the first
It is the same as the structure of each part in the power QFN of the embodiment.

Although the description of the manufacturing process in the present embodiment is omitted, the sealing tape in the resin sealing process as well as the die bonding process for mounting the semiconductor chip on the die pad, the wire bonding process for forming the thin metal wires, and the like. Basically, the manufacturing method according to the first embodiment described above, such as a method for interposing the sealing tape between the lead frame and the sealing die, and supplying the sealing tape with a roll for eliminating wrinkles of the sealing tape. The process can be applied almost as it is.

According to the power QFN of the present embodiment, since the gravity of the semiconductor chip 4 is not applied to the DB paste 7 in the die bonding process, the DB paste 7 hardly spreads on the die pad 2 due to the surface tension of the DB paste 7. Therefore, the area of the region where the semiconductor chip 4 and the die pad 2 are in contact with each other with the DB paste 7 sandwiched therebetween can be reduced, and the moisture resistance of the power QFN can be favorably maintained due to the above-described effects. Further, by supporting the semiconductor chip 4 by the suspension leads 3, the stability of chip support is also kept high.

(Other Embodiments) In each of the above embodiments, the present invention is applied to the resin-sealed semiconductor device (power QFN) that houses the semiconductor chip 4 having the power element built therein. The present invention can also be applied to a resin-sealed semiconductor device that houses a semiconductor chip containing an element that does not generate much heat.

[0107]

According to the lead frame of the present invention, in the lead frame used for manufacturing the resin-sealed semiconductor device, the suspension lead is provided with a rising portion higher than other portions, and the central portion of the die pad is Since I made it up-set from the peripheral part and made it function as a chip support part,
It is possible to improve the selectivity of the size of the semiconductor chip that can be mounted on the lead frame and to form a resin-sealed semiconductor device having high moisture resistance.

According to the first resin-encapsulated semiconductor device of the present invention, a part of the signal lead projects downward from the lower surface of the encapsulation resin to function as an external terminal, and the suspension lead has a higher function than the other part. While providing a raised rising part,
Since the semiconductor chip is mounted in the central part by upsetting the central part of the die pad from the peripheral part, it is possible to improve the selectivity and the moisture resistance of the semiconductor chip.

The structure of the first resin-encapsulated semiconductor device can be easily realized by the method for manufacturing a resin-encapsulated semiconductor device of the present invention.

[0110]

[Brief description of drawings]

FIG. 1 shows a power QFN according to a first embodiment of the present invention.
It is sectional drawing in the Ia-Ia line, and the top view of power QFN.

FIG. 2 is a rear view of the power QFN according to the first embodiment.

FIG. 3 is a step of preparing a lead frame in the manufacturing process of the first embodiment, which is a state when the lead frame is patterned from a copper alloy plate, and a state after the lead frame is pressed. It is a top view which respectively shows.

FIG. 4 is a cross-sectional view showing a change in cross-sectional shape when a die pad of a lead frame is subjected to a semi-cutting process in the manufacturing process of the first embodiment.

FIG. 5 is a cross-sectional view showing a step of joining a semiconductor chip onto a die pad in the manufacturing process of the first embodiment.

FIG. 6 is a cross-sectional view showing a step of forming a thin metal wire in the manufacturing process of the first embodiment.

FIG. 7 is a cross-sectional view showing a step of interposing the sealing tape between the lead frame and the sealing die in the manufacturing process of the first embodiment.

FIG. 8 is a cross-sectional view showing a resin sealing step in the manufacturing process of the first embodiment.

9A and 9B are a plan view of a lower mold used in the first embodiment and a cross-sectional view showing a resin-sealed state.

FIG. 10 is a perspective view for schematically explaining a resin sealing device provided with a sealing tape supply device and a resin sealing procedure in the first embodiment.

FIG. 11 is a cross-sectional view showing a state inside a sealing die during resin sealing in the manufacturing process of the first embodiment.

FIG. 12 is a plan view of a lead frame for forming a power QFN according to a second embodiment of the present invention, and a back view of the power QFN after resin sealing.

FIG. 13 is a plan view of a lead frame used for a power QFN according to a third embodiment of the present invention, a sectional view taken along line XIIIb-XIIIb, and a sectional view taken along line XIIIc-XIIIc.

FIG. 14 is a perspective view of a lead frame according to a third embodiment.

FIG. 15 is a back view of a power QFN obtained by using the lead frame of the third embodiment.

FIG. 16 is a sectional view of a power QFN according to a fourth embodiment of the present invention.

17 is a perspective view of a conventional power QFN, a cross-sectional view taken along line XVIIb-XVIIb of FIG. 17A, and a rear view of the conventional power QFN, respectively.

[Explanation of symbols]

1 Signal lead 2 die pad 3 suspension leads 4 semiconductor chips 5 thin metal wires 6 Sealing resin 7 DB paste 9 External electrode 11 Semi-cut section 12 narrow groove 13 Bend 14 Bend 15 sealing tape 20 lead frame 21 Outer frame 31 die 32 punch 51 sealing mold 51a Upper mold 51b Lower mold 52 Vacuum drawing groove 53 Vacuum draw hole 55 Resin-sealed semiconductor device 56a Unwinding roll 56b winding roll 58 piston 60 Semiconductor Product Molding Department 61 Sealing resin flow path 62 resin tablets 63 resin

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Fumito Ito 1-1 Sachimachi, Takatsuki City, Osaka Prefecture Matsushita Electronics Industrial Co., Ltd. (72) Takahiro Matsuo 1-1 Sachimachi, Takatsuki City, Osaka Matsushita Electronic Industry Co., Ltd. (56) Reference JP-A-10-12793 (JP, A) JP-A-3-149864 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 23/50

Claims (12)

(57) [Claims] 1. A lead frame used for manufacturing a resin-encapsulated semiconductor device, comprising: an opening provided in a region where a semiconductor chip is to be mounted; an outer frame surrounding the opening; and an inside of the opening. A die pad for supporting the semiconductor chip, a plurality of suspension leads for supporting the die pad, and a plurality of signal leads connected to the outer frame at the edge of the opening and extending toward the die pad. Each of the suspension leads is formed with a rising portion that is higher than other portions, and the central portion of the die pad is upset from its peripheral portion to support the semiconductor chip. It functions as a chip support part of the above, and the rising part of the suspension lead is a part close to the die pad.
Inclining from the minute toward the outside so that its height position decreases
Lead frame characterized by being inclined . 2. The lead frame according to claim 1, wherein the central portion of the die pad is upset from the peripheral portion by a semi-cut portion. 3. The lead frame according to claim 1, wherein an upper surface of a central portion of the die pad is located above an uppermost surface of a rising portion of the suspension lead. 4. The lead frame according to claim 1, wherein a punched portion is present between the central portion and the peripheral portion of the die pad. Lead frame to 5. A semiconductor chip, a die pad for supporting the semiconductor chip, an adhesive member for adhering the semiconductor chip onto the die pad, a plurality of suspension leads for supporting the die pad, and a facing toward the die pad. A plurality of extending signal leads, a connecting member for electrically connecting the semiconductor chip and the signal lead to each other, a semiconductor chip, a die pad, an adhesive member, a connecting member, a suspension lead and a signal lead are sealed. A resin-encapsulated semiconductor device having a sealing resin for stopping, wherein a part of the signal lead projects below the lower surface of the sealing resin and functions as an external terminal. The lead has a rising part that is higher than other parts, and the center part of the die pad is upset from the peripheral part. The semiconductor chip may be mounted on a said central portion, the lower surface of the semiconductor chip, the top surface of the suspension leads
A resin-encapsulated semiconductor device characterized in that it is located above the top . 6. The resin-encapsulated semiconductor device according to claim 5, wherein the rising portion of the suspension lead is inclined so that the height position thereof becomes lower from the portion near the die pad toward the outside. A resin-encapsulated semiconductor device comprising: 7. The resin-encapsulated semiconductor device according to claim 5 , wherein a punched portion is present between the central portion and the peripheral portion of the die pad, and the central portion of the die pad is A resin-encapsulated semiconductor device characterized in that the encapsulating resin is also embedded in the lower part. 8. The resin-encapsulated semiconductor device according to claim 5 , wherein a closed loop groove is formed on a lower surface of a peripheral portion of the die pad. Sealed semiconductor device. 9. A step (a) of preparing a semiconductor chip, an opening provided in a region where the semiconductor chip is to be mounted, an outer frame surrounding the opening, and a semiconductor chip disposed in the opening and supporting the semiconductor chip. A suspension pad for supporting the die pad, a plurality of suspension leads for supporting the die pad, and a plurality of signal leads connected to the outer frame at the edge of the opening and extending toward the die pad. Part (b) is a rising part that is higher than other parts, and a step (b) of preparing a lead frame in which the central part of the die pad is upset from the peripheral part thereof; and the die pad of the lead frame. (C) fixing the semiconductor chip on the central portion of the semiconductor chip, and electrically connecting the semiconductor chip and the signal lead to each other by a connecting member. In the step (d) of electrically connecting, a sealing tape is interposed between the back surface of the lead frame and the sealing die, and a mold clamping force is applied to the lead frame and the sealing tape, A method of manufacturing a resin-encapsulated semiconductor device, comprising the step (e) of encapsulating the semiconductor chip, die pad, connecting member, suspension lead, and signal lead with an encapsulating resin. 10. The method for manufacturing a resin-encapsulated semiconductor device according to claim 9 , wherein in the step (e), a mold clamping force is applied to the outer frame of the lead frame and the sealing tape. Method for manufacturing a resin-encapsulated semiconductor device. 11. The method for manufacturing a resin-encapsulated semiconductor device according to claim 9 or 10 , wherein in the step (a), a closed loop groove is formed on a lower surface of a peripheral portion of the die pad. Method for manufacturing a resin-encapsulated semiconductor device. 12. The method for manufacturing a resin-encapsulated semiconductor device according to claim 9 , wherein in the step (a), punching is performed between a central portion and a peripheral portion of the die pad. A method of manufacturing a resin-encapsulated semiconductor device, comprising forming a portion.