JP3153197B2 - 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, and more particularly to an SON for realizing a thin semiconductor device.
(Small Outline Non-lead P
As in the case of the package structure, a portion of the external terminal portion of the lead is embedded in the sealing resin while the lower surface is exposed, and the lower surface of the external terminal portion and the sealing resin bottom surface are substantially flat. The present invention relates to a structure of a lead of a fixed semiconductor device.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for smaller and thinner semiconductor devices. One solution to this requirement is SON (Small Outline).
A resin-sealed semiconductor device having a structure in which leads are exposed from the bottom surface of a sealing resin like a non-lead package structure has been proposed.

FIG. 8 is a diagram schematically showing a first conventional example of this type of resin-sealed semiconductor device, and FIG.
FIG. 8B is a cross-sectional view of the first conventional example corresponding to a cross section taken along the line AA ′ of FIG. 1, and FIG. 8B is a plan view of the resin-sealed semiconductor device 100 of the first conventional example viewed from the back.

[0004] Referring to FIG. 8, a depressed lead 110 of a resin-encapsulated semiconductor device 100 has an internal terminal portion 111, a connection portion 112 and an internal terminal 111 electrically connected to a semiconductor chip 140 by, for example, a bonding wire 150. It includes an external terminal portion 113, a connection portion between the internal terminal portion 111 and the connection portion 112, and a connection portion 112 and the external terminal portion 113.
Each of the connecting portions is bent. The semiconductor chip 140 is mounted and fixed to the island 130 via a conductive adhesive or the like (not shown), and the internal terminal portion 111, the connecting portion 112, a part of the external terminal portion 113, the island 130, and the semiconductor chip 140 are sealed. Stop resin 120
It is sealed with. Further, the lower surface of the external terminal portion 113 is substantially flat with the bottom surface of the sealing resin 120 and is not covered with the sealing resin 120 but is exposed.

As a second conventional example, Japanese Patent Laid-Open No.
Japanese Patent No. 40940 discloses a resin-sealed semiconductor device of this type together with a method of manufacturing the same.

FIG. 9 is a sectional view showing a manufacturing method disclosed in Japanese Patent Application Laid-Open No. 2-240940. Referring to FIG. 9, in a semiconductor device 200 of the second conventional example, convex electrodes 210 and 23 are provided on one surface of a flat supporting portion 271.
The adhesive 230 is applied on the electrode 230 using the lead frame 270 provided with the
Are mounted, and the electrode 210 and the integrated circuit element 240 are connected to each other by a connector 250, and at least the integrated circuit element 240
After covering the connection member 250 with the sealing resin 220, the other surface of the support portion 271 is removed until the electrode 210 is exposed (for example, by grinding with a surface grinder provided with a grindstone 290), so that the outside is removed. A connection terminal is formed.

[0007]

First, in the first conventional example, as shown in FIG. 8 (a), when the lead is depressed, the bending at the connecting portion between the connecting portion 112 and the external terminal portion 113 is performed. In processing, an edge (corner) cannot be obtained, and an R portion (roundness) is formed. For this reason, FIG.
As shown in FIG. 8B, the boundary between the lead and the sealing resin (FIG. 8)
There is a drawback that thin resin burrs are irregularly generated in the (Q part) of (b) and the shape of the exposed surface of the external terminal part is not stable.
It has been required to reduce this resin burr.

Further, when the manufacturing method as in the second conventional example is used, irregular occurrence of thin resin burrs at the boundary between the electrode 210 (lead) and the sealing resin 220 is suppressed, In addition to the assembling step, an additional step of backside polishing is required, and there is a problem that the assembling processing cost increases.

According to the present invention, there is provided a resin-encapsulated semiconductor device having a structure in which a lead is exposed from the bottom surface of a sealing resin, such as an SON structure, in an external terminal at a boundary between an external terminal portion of the lead and the sealing resin. A sealed semiconductor device in which the shape of the external terminal portion exposed surface is stabilized by suppressing the occurrence of thin resin burrs on the portion, without adding a process such as back surface polishing after resin sealing, The purpose is to provide it at low cost.

[0010]

According to the present invention, there is provided a semiconductor device comprising:
In a semiconductor device including a semiconductor chip, a lead electrically connected to the semiconductor chip, and a sealing resin for sealing the semiconductor chip and at least a part of the lead, the lead is at least the semiconductor chip An internal terminal portion electrically connected to the semiconductor device, an external terminal portion connected to a conductor on the circuit board when the semiconductor device is mounted on the circuit board, and connecting the internal terminal portion and the external terminal portion. And a concave portion that crosses the connecting portion in the width direction on a surface of the first end portion of the connecting portion that is connected to the external terminal portion and that is continuous with a lower surface of the external terminal portion. The connecting portion including at least the semiconductor chip, the internal terminal portion of the lead, and the recess, and the external portion, wherein the connecting portion includes at least a first end of the connecting portion and a depressed bending process. The lower surface of the portion of the terminal portion is the sealed in the sealing resin and the external terminal portions are exposed on the bottom surface of the sealing resin, further wherein said semiconductor chip and the leads
The internal terminals are connected via bumps. This half
Inside of the lead where the conductor chip is depressed and bent
When connected to the top side of the terminal,
Heat sink made of high thermal conductivity material
Can Ru.

[0011] In addition, other semiconductor device of the present invention relates to a semiconductor
The chip is electrically connected to the semiconductor chip
Lead, semiconductor chip and at least a part of lead
And a sealing resin for sealing.
An internal terminal electrically connected to the semiconductor chip;
When mounting the device on a circuit board,
Connected external terminal, internal terminal and external terminal
And a connecting portion for connecting the connecting portion, wherein the thickness of the connecting portion is
1/3 to 3/4 of the thickness of the terminal part and the external terminal of the connecting part
Depressed at the first end connected to the semiconductor chip and at least the internal terminal of the semiconductor chip and the lead.
A part of the connecting portion and the external terminal portion is sealed with the sealing resin and
The lower surfaces of the terminal portions are exposed on the bottom surface of the sealing resin.

The lead recess of the semiconductor device of the present invention is
It can be formed by chemical etching or coining.

At this time, the depth of the recess is preferably about 1/4 to 2/3 of the lead thickness in order to obtain a good depressed bending shape while maintaining the lead strength.

Further, in the semiconductor device of the present invention, when the semiconductor device is mounted on a circuit board, the surface of the external terminal portion that contacts the conductor on the circuit board is flat with the bottom surface of the sealing resin. Alternatively, it can protrude from the bottom surface of the sealing resin within a range not exceeding the depth of the concave portion formed in the connecting portion.

[0015]

Next, the present invention will be described with reference to the drawings.

In the following description, an example in which leads are provided on four sides of a semiconductor device will be used. However, it is needless to say that the same can be applied to a case in which leads are provided on only two opposite sides.

FIG. 1 shows a semiconductor device of the present invention and a semiconductor device of the present invention.
Related a schematic appearance perspective view of one technique, Figure 3 (from figure B direction) of the semiconductor device of FIG. 1 from the bottom side is a plan view. 2 (a) and 2 (b) respectively show the present invention.
FIG. 1 is a cross-sectional view and a cross-sectional view taken along line AA ′ of FIG.
FIG. 2 is an enlarged cross-sectional view illustrating a main part of a mode.

Referring to FIGS. 1 to 3, a semiconductor device according to the related art of the present invention includes a depressed bent lead 10 including an inner terminal portion 11, a connecting portion 12, and an outer terminal portion 13,
The semiconductor device includes a semiconductor chip mounted on the island, a bonding wire for electrically connecting the semiconductor chip to the lead, and a part of the internal terminal portion, the connection portion and the external terminal portion of the lead, Island 30,
The semiconductor chip 40 and the bonding wires 50 are sealed with the sealing resin 20. Depress bending of the lead 10 is performed at the first end 15 and the second end 16 respectively. In the first end 15, a concave portion 14 is formed on a surface opposite to the bending direction at the first end 15 (a surface on the lower surface 13 b side of the external terminal portion) over the entire width of the connecting portion 12. The recess 14 is also sealed with the sealing resin 20.

The upper surface 13a and a part of both side surfaces of the external terminal portion 13 are sealed with the sealing resin 20, while the lower surface 13b is substantially flat with the bottom surface of the sealing resin 20 and It is not covered with but exposed and serves as an external electrode.

Next , a lead frame for realizing the lead of the semiconductor device of the present invention will be briefly described.

FIG. 4 is a schematic plan view of a lead frame 70 used for manufacturing the semiconductor device of the present invention, and FIG.
FIG. 5 is an enlarged view of a portion centered on the lead of FIG.
FIG. 5A is an enlarged plan view of a portion centered on a lead, and FIG.
FIG. 5B is a cross-sectional view taken along the line XX ′ of FIG.
FIG. 5C is a schematic plan view of FIG. 5B viewed from above.

An example of a method for manufacturing the lead frame shown in FIGS. 4 and 5 is as follows.

First, after forming the leads 10, the islands 30, etc. by using a known press technique or etching technique, the external terminal portions 13 of the respective leads 10 and the connecting portions 12 are formed.
A concave portion 14 having a predetermined opening width h is formed in advance on the connecting portion side (first end portion 15) of the boundary portion with the portion. At this time, the recess 32 may be formed also in the suspension lead 31 supporting the island 30. Then, after subjecting a predetermined area to surface treatment such as plating, the lead 10 is subjected to depress bending using a known bending technique. If necessary, the island suspension leads 31 are also depressed and bent.

As described above, the lead frame 70 used for manufacturing the semiconductor device of the present invention is completed.

The surface on which the recess 14 is formed is a surface opposite to the depressing bending direction at the first end 15, in other words, a surface that is continuous with the lower surface 13 b of the external terminal portion.

As the means for forming the concave portion 14, a method based on coining technology is possible in addition to chemical etching. The depth d of the concave portion 14 (see FIG. 5B) is preferably １ ／ to の of the lead thickness D of the connecting portion 12 in consideration of the steepness of the rising at the time of bending and the lead strength. Further, the opening width h of the concave portion 14 is sufficient if it is about 0.2 mm or more, and the concave portion 14 can be formed by reducing the thickness of the entire connecting portion 12.

The manufacturing of the semiconductor device 1 according to the related art of the present invention is performed by a lead for realizing the lead of the semiconductor device of the present invention.
This is performed as follows using the same lead frame 70 as the lead frame.

First, the semiconductor chip 40 is mounted and fixed (die-bonded) to the island 30 of the lead frame 70 via a conductive adhesive (for example, silver paste) or the like (not shown). 11 is wire-bonded with a bonding wire 50 of a thin metal wire such as a gold wire, and is transfer-molded with a sealing resin 20, whereby the semiconductor device 1 according to the related art of the present invention can be manufactured.

In the manufacture of the semiconductor device 1,
The manufacturing equipment used in any of the processes such as die bonding, wire bonding, and transfer mold encapsulation can be used because it has been used in the past, and there is no need to prepare special new manufacturing equipment or modify existing manufacturing equipment. is there.

Next, first and second embodiments of the semiconductor device of the present invention will be described. In these embodiments, the processing of the recess for the lead frame used is:
Since what has been performed by the above-described lead frame manufacturing method is used, the description thereof is omitted.

FIGS. 6 (a) and 6 (b) show the first and the second, respectively.
FIG. 4 is a cross-sectional view schematically illustrating a cross section taken along line AA ′ in FIG. 1 of the semiconductor device according to a second embodiment. These second and first
In each of the embodiments, the internal terminal portion 11 and the semiconductor chip 40 are connected via the bump 60.

Referring to FIG. 6A, in the semiconductor device 1 of the first embodiment, the semiconductor chip 40 is resin-sealed face down, and the back surface thereof is formed of a high thermal conductivity material such as metal. The radiating plate 80 is fixed with a heat conductive adhesive (not shown) (not shown), and the surface of the radiating plate 80 opposite to the surface on which the semiconductor chip 40 is mounted is exposed from the sealing resin 20. It is almost flat with the sealing resin 20. Therefore, the semiconductor device of this embodiment is excellent in heat dissipation, and is more effective for a semiconductor chip which consumes a large amount of power and generates a large amount of heat.

Referring to FIG. 6B, in the semiconductor device 1 of the second embodiment, the semiconductor chip 40 has bumps 60 on the lower surface side of the depressed and bent internal terminal portions 11.
And is more effective when applied to make the semiconductor device 1 thinner.

Next, a third embodiment of the semiconductor device of the present invention will be described.

FIG. 7 is a cross-sectional view schematically showing a cross section taken along the line AA ′ in FIG. 1 of the semiconductor device of the third embodiment.

Referring to FIG. 7, in the semiconductor device 1 of the third embodiment, when the semiconductor device 1 is mounted on a circuit board, the external terminal portions 3 contacting the conductors on the circuit board.
Is lower than the bottom surface of the sealing resin 20 by t (however,
0 <t <depth d of recess 14) Projecting. By doing so, when mounting the semiconductor device 1 on a circuit board,
Even if there are some irregularities on the circuit board, it is possible to mount the circuit stably.

[0037]

According to the semiconductor device 1 of the present invention, as described above,
The concave portion 1 is formed on the surface of the connecting portion 12 on which the lead 10 is subjected to the depressing bending process, on the surface opposite to the bending direction of the first end portion 15.
4, the rising of the connecting portion 12 is much steeper than in the conventional example having no concave portion 14.

As a result, the semiconductor device 1 of the present invention has a boundary portion between the end of the external terminal portion 13 and the sealing resin 20 ( P in FIG. 3 ).
Portion) became clear, and a great effect that the generation of thin burrs in the external terminal portion 13 at the time of transfer molding sealing with the sealing resin 20 can be greatly suppressed was obtained.

Further, since the generation of the thin burrs can be suppressed, the lower surface 13b of the external terminal portion can be reliably exposed in a stable shape, the deburring process can be simplified, and extra stress can be applied. As a result, a package crack can be avoided, and a great effect of improving the mountability can be obtained.

When manufacturing the lead frame,
By forming the concave portion, the stress was relieved, and the effect of improving the reproducibility of the depressing bending was also obtained.

The semiconductor device of the present invention can be realized by a conventional assembling process simply by performing an additional process of providing a concave portion when manufacturing a lead frame, and can be realized by capital investment for a new manufacturing device or an existing manufacturing device. It is also a great effect that the present invention can be realized without requiring modification or the like.

[Brief description of the drawings]

FIG. 1 is an external perspective view schematically showing a semiconductor device according to the present invention and related technology of the present invention .

FIGS. 2A and 2B are cross-sectional views taken along the line AA ′ in FIG. 1 of the semiconductor device according to the related art of the present invention; FIG. 2A is a cross-sectional view of the entire line AA ′; FIG.

FIG. 3 shows the semiconductor device of FIG. 1 on the bottom side (from the direction B in the figure)
FIG.

FIG. 4 is a schematic plan view of a lead frame used for manufacturing a semiconductor device of the present invention.

FIG. 5 is an enlarged view of a portion centered on the lead in FIG . 4, (a) is an enlarged plan view of a portion centered on the lead,
(B) is a sectional view taken along line XX 'of (a), and (c) is a schematic plan view of (b) as viewed from above.

FIG. 6 is a diagram illustrating first and second embodiments of the present invention.
In, (a), (b), respectively, first, the A-A 'sectional view of FIG. 1 of the semiconductor device of the second embodiment is a cross-sectional view schematically showing.

FIG. 7 is a cross-sectional view schematically showing a cross section taken along line AA ′ of FIG. 1 of a semiconductor device according to a third embodiment of the present invention;

8A and 8B are diagrams schematically showing a first conventional example, and FIG.
1 is a cross-sectional view of a corresponding first conventional example, and FIG. 2B is a plan view of the resin-sealed semiconductor device of the first conventional example viewed from the back surface.

FIG. 9 is a cross-sectional view illustrating a manufacturing method according to a second conventional example.

[Explanation of symbols]

 1,100,200 Semiconductor device 10,110 Lead 11,111 Internal terminal portion 12,112 Connecting portion 13,113 External terminal portion 13a Upper surface of external terminal portion 13b Lower surface of external terminal portion 14 Recess 15 First end 16 First Ends of 2, 20, 120, 220 Sealing resin 30, 130 Island 31 Suspended lead 32 Suspended lead recess 40, 140 Semiconductor chip 50, 150 Bonding wire 60 Bump 70, 270 Lead frame 80 Heat sink 210, 230 Electrode 231 Adhesion Agent 240 integrated circuit element 250 connector 271 support 290 grindstone

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-11-330343 (JP, A) JP-A-2000-49270 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 23/50 H01L 21/56 H01L 23/28

Claims (11)

(57) [Claims] 2. A semiconductor device comprising: a semiconductor chip; a lead electrically connected to the semiconductor chip; and a sealing resin for sealing the semiconductor chip and at least a part of the lead. At least an internal terminal electrically connected to the semiconductor chip, an external terminal connected to a conductor on the circuit board when the semiconductor device is mounted on the circuit board, and an internal terminal connected to the external terminal. And a connecting portion for connecting the terminal portion to the external terminal portion. The connecting portion is connected to the external terminal portion at a first end connected to a lower surface of the external terminal portion. The connection including at least the semiconductor chip, the internal terminal portion of the lead, and the concave portion, wherein the connection portion includes a concave portion that crosses the semiconductor chip, and is depressed at least at a first end of the connection portion. Department and the lower surface of the portion of the external terminal portion is sealed in the sealing resin and the external terminal portion is exposed at the bottom of the sealing resin and further the semiconductor chip and the front
A semiconductor device , wherein the internal terminals of the leads are connected via bumps . 2. A high thermal conductivity material is formed on the back surface of the semiconductor chip.
The semiconductor device of claim 1, wherein that having a made the radiating plate further. 3. A semiconductor chip, and the semiconductor chip and an
A lead electrically connected, the semiconductor chip and
A sealing resin for sealing at least a part of the lead.
In the semiconductor device, the lead is at least
An internal terminal portion electrically connected to the semiconductor chip;
When mounting a semiconductor device on a circuit board,
An external terminal connected to a conductor, the internal terminal,
And a connecting portion for connecting to an external terminal portion.
A first end connected to the external terminal of the connection portion;
Connect the connecting part in the width direction on the surface
Having a transverse recess and at least the connecting portion
Depressed bending at the first end, at least
The semiconductor chip and the internal terminal portion of the lead;
The connecting portion including the recess and a part of the external terminal portion are sealed.
Sealed with resin and the lower surface of the external terminal portion is sealed
Exposed on the bottom of the resin, and further depressed
Via a bump on the lower surface side of the internal terminal portion of the lead
And the semiconductor chip is connected to the
That the semiconductor device. 4. The concave portion forming surface of the lead is provided
On the side of the lead opposite to the bending direction of the press bending process
The semiconductor device according to one of claims 1 to 3 any one. Wherein the concave portion is formed by a chemical etching
Semiconductor device according to any one of claims 1 to 3. 6. The recess is formed by coining.
The semiconductor device according to claim 1 . 7. A depth of the recess, the consolidated portion of the lead thickness
The semiconductor device according to any one of claims 1 to 6, which is a 1/4 to 2/3. 8. A semiconductor chip, and the semiconductor chip and an electric
A lead electrically connected, the semiconductor chip and
A sealing resin for sealing at least a part of the lead.
In the semiconductor device, the lead is at least
An internal terminal portion electrically connected to the semiconductor chip;
When mounting a semiconductor device on a circuit board,
An external terminal connected to a conductor, the internal terminal,
And a connecting portion for connecting to an external terminal portion.
The thickness of the connecting portion is 1/3 to 3/4 of the thickness of the external terminal portion.
And a first terminal connected to the external terminal portion of the connecting portion.
Depressed bending at the end, at least the half
The conductor chip, the internal terminal portion of the lead, and the connection portion
And a part of the external terminal portion is sealed with the sealing resin, and
The lower surface of the external terminal portion is exposed at the bottom of the sealing resin
A semiconductor device. 9. A connecting portion connected to an external terminal portion of a lead .
At the first end, the bending direction of the depress bending
9. The semiconductor device according to claim 8 , wherein the surface of the lead on the opposite side has a step . 10. A bottom surface of an external terminal portion is a bottom surface of a sealing resin.
The semiconductor device according to any one of claims 1 to 9 is flat. 11. lower surface of the outer portion the terminal portion, the bottom surface of the sealing resin
More protruding, and the protruding amount is formed on the connecting portion.
And does not exceed the depth of the recess are claims 1 to 7 or 1
13. The semiconductor device according to item 9.