JP2001077130A - Manufacture of resin sealed semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a resin sealed semiconductor device, where no defect or chipping takes place at a lead or sealing resin in a cutting process where the resin sealed semiconductor device is separated from a lead frame or substrate, for enhanced productivity. SOLUTION: When cutting a lead after a metal sheet 13 is allowed to tightly contact a lead 4 before resin sealing, the metal sheet 13 together with the lead 4 are cut completely to prevent occurrence of a burr (metal burr) on the cut surface of the read part 4. In particular, with the metal sheet harder than the lead part 4, common-cut effect is enhanced, the occurrence of a burr is prevented, and lead cutting can be made.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a QFN (Quad).
Flat Non-leaded Package)
The present invention relates to a method for manufacturing a small / thin resin-encapsulated semiconductor device in which a lead portion serving as an external terminal is sealed on one side, and particularly to improve production efficiency and reliability of the lead portion. And a method for realizing a resin-sealed semiconductor device.

[0002]

2. Description of the Related Art In recent years, in order to cope with miniaturization of electronic equipment, high-density mounting of semiconductor components such as resin-encapsulated semiconductor devices has been required.
Thinning is progressing. In addition, the number of pins has been increased while being small and thin, and a high-density small and thin resin-sealed semiconductor device has been demanded.

Hereinafter, a lead frame used in a conventional QFN-type resin-sealed semiconductor device will be described.

FIG. 21 is a view showing the structure of a conventional lead frame, and FIG. 21 (a) is a plan view, and FIG.
FIG. 22B is a cross-sectional view taken along a line A-A1 in FIG.

As shown in FIG. 21, a conventional lead frame comprises a frame 101 and a rectangular die pad 10 on which a semiconductor element is mounted.
2 and a suspension lead 1 having a corner portion of the die pad portion 102 supported at its tip end and an end portion connected to the frame 101.
03, and a beam-shaped lead portion 104 electrically connected to the mounted semiconductor element by a connecting means such as a thin metal wire when the semiconductor element is mounted. When the lead portion 104 is sealed with the sealing resin, a portion embedded in the sealing resin portion constitutes an inner lead portion 104a, and a portion exposed from the sealing resin portion constitutes an outer lead portion 104b. And the inner lead portion 10
4a and the outer lead portion 104b are provided integrally and continuously. In FIG. 21, a region indicated by a broken line indicates a region sealed with a sealing resin when a semiconductor element is mounted to form a resin-sealed semiconductor device, and a portion indicated by a dashed line indicates After the semiconductor element is mounted and resin-sealed to form a resin-sealed semiconductor device, the lead 1
FIG. 4 shows a portion where the outer lead portion 104b is cut by a mold.

FIG. 21 shows a conventional lead frame.
As shown in (b), the die pad portion 102 is supported by the suspension lead portion 103, and the die pad portion 10 is supported by the depress portion provided on the suspension lead portion 103.
2 is set up so as to be disposed above the upper surface of the lead portion 104.

Next, a conventional resin-sealed semiconductor device will be described. FIG. 22 is a view showing a resin-sealed semiconductor device using the lead frame shown in FIG.
(A) is a perspective plan view showing the internal configuration by a broken line,
FIG. 22B is a cross-sectional view taken along a line B-B1 in FIG.

As shown in FIG. 22, a semiconductor element 105 is mounted on a die pad section 102 of a lead frame, and the semiconductor element 105 and an inner lead section 104a of the lead section 104 are electrically connected by a thin metal wire 106. I have. Then, the semiconductor element 10 on the die pad portion 102
5. The outer periphery of the inner lead portion 104a is the sealing resin 107.
Is sealed. The bottom portion of the lead portion 104 (the inner lead portion 104a) is
Is exposed with a standoff from the bottom surface of the external terminal 1
08. Although the outer lead portion 104b is exposed from the side surface of the sealing resin 107, it is substantially the same as the side surface of the sealing resin 107.

Next, a method of manufacturing a conventional resin-encapsulated semiconductor device will be described.

[0010] First, as shown in FIG.
In the frame, the semiconductor device is mounted in a rectangular shape, and the upset die pad portion 102 and the corners of the die pad portion 102 are supported at their tip portions, and the ends are connected to the frame frame. When the semiconductor device is mounted on the suspension lead portion, the beam-shaped lead portion 10 electrically connected to the mounted semiconductor device by connecting means such as a thin metal wire.
4 is prepared.

Then, as shown in FIG. 24, the semiconductor element 10 is placed on the die pad 102 with an adhesive such as a silver paste.
5 is mounted and bonded.

Next, as shown in FIG.
02 and the inner lead 1 of the lead 104 on the surface of the semiconductor element 105 mounted on the
04a is electrically connected with the thin metal wire 106.

Next, as shown in FIG.
The sealing sheet 109 is brought into close contact with at least the bottom surface of the lead portion 104 of the lead frame in which 5 is mounted. The sealing sheet 109 is a member for protecting the sealing resin from flowing around the bottom surface of the lead portion 104 and exposing the bottom surface of the lead portion 104.

Next, as shown in FIG. 27, the lead frame is placed in a mold, and the lead portion 104 is pressed against the sealing sheet 109 by the mold. Is implanted to seal the upper surface area of the die pad portion 102, the semiconductor element 105, the lead portion 104, and the connection region of the thin metal wire 106 as the outer periphery of the lead frame. FIG. 28 shows a state where the outer periphery is sealed with a sealing resin 107.

Next, as shown in FIG. 29, the sealing sheet adhered to the bottom surface of the lead portion 104 of the lead frame is removed by peeling off or the like.

Next, as shown in FIG.
Is cut with a cutting blade 111 using a die.

As shown in FIG. 31, a semiconductor element 105 is mounted on a die pad section 102 of a lead frame, and the semiconductor element 105 and an inner lead section 104a of the lead section 104 are electrically connected by a thin metal wire 106. The outer periphery is sealed with a sealing resin 107, and the bottom surface of the lead portion 104 (inner lead portion 104 a) is exposed with a standoff from the bottom surface of the sealing resin 107 to form an external terminal 108. At the same time, the outer lead portion 104b is exposed from the side surface of the sealing resin 107, and a resin-sealed semiconductor device having substantially the same surface as the side surface of the sealing resin 107 is obtained.

[0018]

However, in a conventional lead frame and a method of manufacturing a resin-encapsulated semiconductor device using the same, particularly after the lead frame is resin-encapsulated, the lead is cut by a cutting blade of a mold. Since the cutting was performed, in the cutting process, there were problems such as resin chips and cracks occurring in the sealing resin portion adjacent to the lead portion due to the impact at the time of lead cutting, and the lead portion falling off from the sealing resin portion. there were. Since the structure of the conventional resin-encapsulated semiconductor device is a so-called single-sided encapsulation structure in which only the upper surface of the lead portion is covered with an encapsulating resin, the lead cutting by the cutting blade of the mold causes an The lead portion and the sealing resin portion were easily damaged.

Furthermore, in recent years, a semiconductor device has been mounted on a large-sized lead frame substrate, connected with thin metal wires, and then encapsulation has been progressing in which the outer periphery is entirely sealed. In the case where the entire structure is covered with the sealing resin, not only the lead cut but also the sealing resin portion must be cut, and thus the problem that the cutting means using the cutting blade of the mold cannot cope with the problem has become apparent. .

The present invention provides a method of manufacturing a resin-encapsulated semiconductor device which can cope with the above-mentioned conventional problems and future trends in the manufacturing process of the resin-encapsulated semiconductor device.
Provided is a method for manufacturing a resin-encapsulated semiconductor device that improves productivity and does not cause defects or defects in a lead portion and an encapsulation resin portion in a cutting step when separating the resin-encapsulated semiconductor device from a lead frame and a substrate. Things.

[0021]

In order to solve the above-mentioned conventional problems, a method of manufacturing a resin-encapsulated semiconductor device according to the present invention comprises a frame main body made of a metal plate and a substantially central region of the frame main body. A die pad portion for mounting the semiconductor element, a suspension lead portion supporting the die pad portion at the tip end, and connected to the frame at the other end portion, at least the tip end portion extends toward the die pad portion. A step of preparing a lead frame having a lead portion having the other end connected to the frame frame, and a cut portion provided in the vicinity of a region of the lead portion connected to the frame frame; and A step of mounting a semiconductor element on a die pad portion; and an electrode pad on a main surface of the semiconductor element mounted on the die pad portion, and each upper surface of a lead portion of the lead frame. Connecting with a thin metal wire, forming a metal film on at least each bottom surface of the lead portion on the back surface side of the lead frame, applying a pressing force to at least the end of the lead portion, and applying a pressing force to the bottom surface of the lead portion. In the state of being pressed against the metal film, the semiconductor element, the die pad portion, the fine metal wire, and the cutting portion provided near the region where the bottom surface of the lead portion is connected to the frame of the lead portion as the upper surface side of the lead frame. A step of sealing the area except for the resin with a sealing resin, cutting the upper surface of the cut portion of the lead with a blade, cutting the cut portion together with the metal film formed on the lower surface of the cut portion, and sealing the resin. A step of separating the stop-type semiconductor device, and a step of removing the metal film formed on the bottom surface of the separated resin-sealed semiconductor device to obtain a resin-sealed semiconductor device. A method of manufacturing sealed semiconductor devices.

Further, the method of manufacturing a resin-encapsulated semiconductor device according to the present invention is characterized in that a frame main body made of a metal plate, a die pad portion for mounting a semiconductor element disposed in a substantially central region of the frame main body, A supporting lead portion supporting the die pad portion at the other end and connected to the frame frame, at least a leading end portion extends toward the die pad portion, and a lead portion connected at the other end portion to the frame frame, A step of preparing a lead frame including a cut section provided in the vicinity of a region connected to a frame of the lead section; a step of mounting a semiconductor element on the die pad section of the prepared lead frame; Connecting the electrode pads on the main surface of the semiconductor element mounted thereon to the respective upper surfaces of the lead portions of the lead frame by thin metal wires; A step of bringing a sealing sheet into close contact with at least each bottom surface of the lead portion on the back surface side of the program, and applying a pressing force to at least an end of the lead portion, and pressing the bottom surface of the lead portion against the sealing sheet. The semiconductor element as a top surface side of the lead frame, a die pad portion,
A step of resin-sealing a metal thin wire and a region excluding a cut portion provided in the vicinity of a bottom surface of the lead part and a frame connected to the frame of the lead part with a sealing resin, and a step of removing the sealing sheet Forming a metal film on at least each bottom surface of the lead portion on the back surface side of the lead frame; cutting the upper surface of the cut portion of the lead portion with a blade to form a metal film on the lower surface of the cut portion A step of cutting the cut portion together with the film to separate the resin-encapsulated semiconductor device, and a step of removing the metal film formed on the bottom surface of the separated resin-encapsulated semiconductor device to obtain a resin-encapsulated semiconductor device And a method for manufacturing a resin-sealed semiconductor device.

More specifically, the step of forming a metal film on at least each bottom surface of the lead portion on the back side of the lead frame is a step of forming a metal film by closely attaching a metal sheet as the metal film. This is a method for manufacturing a semiconductor device.

In the step of forming a metal film on at least each bottom surface of the lead portion on the back surface side of the lead frame, the metal film is formed by a method of manufacturing a resin-encapsulated semiconductor device in which a metal film of the same material as the lead frame is formed. is there.

In the step of forming a metal film on at least each bottom surface of the lead portion on the back surface side of the lead frame, the metal film is a resin-encapsulated semiconductor device that forms a metal film made of a metal harder than the material of the lead frame. It is a manufacturing method of.

As described above, in the method of manufacturing a resin-sealed semiconductor device according to the present invention, when a lead frame is cut to separate the resin-sealed semiconductor device from a metal, The film is brought into close contact with at least the bottom surface of the lead portion, resin-sealed in that state, and then the lead is cut. Can be prevented from occurring. In this case, since the material of the metal film is particularly harder than the lead portion (lead frame), no burrs are generated on the end surface of the cut lead portion. In addition, since the metal film is a metal sheet, it can be used in a sealing step, and one-side sealing can be performed on a lead portion.
Since the metal sheet is not made of resin, shrinkage is small, generation of a groove at the boundary between the sealed resin and the lead portion can be prevented, and a highly reliable resin-encapsulated semiconductor device can be realized. In addition, since the metal film is made of the same material as the lead frame, the effect of thermal expansion due to heat applied at the time of resin sealing is eliminated, and highly reliable resin sealing and a product can be realized.

Before the resin sealing, a sealing sheet made of resin is brought into close contact with the bottom surface of the lead portion, and thereafter the resin sealing is performed. Later, the metal film is adhered to the bottom surface of the lead part, and the lead is cut in that state, so the blade is cut along with the metal film, so that it cuts together, preventing the occurrence of burrs on the cut end surface of the lead You can do it. That is, the members (sealing sheet, metal film) added to the bottom surface of the lead portion can be changed depending on the contents of the process,
A manufacturing method having a range of choice can be realized.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a lead frame according to the present invention and a method for manufacturing a resin-encapsulated semiconductor device using the same will be described below with reference to the drawings.

First, the lead frame of this embodiment will be described.

FIG. 1 is a view showing a part of the lead frame of the present embodiment, and FIG. 1 (a) is a plan view, and FIG.
FIG. 2B is a cross-sectional view taken along a line C-C1 in FIG.

As shown in FIG. 1, a lead frame according to the present embodiment has a frame 1, a rectangular die pad 2 on which a semiconductor element is mounted, and a corner of the die pad 2. When the semiconductor element is mounted on the suspension lead 3 whose end is connected to the frame frame 1 and the semiconductor element is mounted, the semiconductor chip is electrically connected to the mounted semiconductor element by connecting means such as a thin metal wire. And a beam-shaped lead portion 4. When the lead portion 4 is sealed with the sealing resin, a portion embedded in the sealing resin portion constitutes an inner lead portion 4a, and a portion exposed from the sealing resin portion constitutes an outer lead portion 4b. The inner lead portion 4a and the outer lead portion 4b are provided integrally and continuously. In FIG. 1, a region indicated by a broken line indicates a region to be sealed with a sealing resin when a semiconductor element is mounted to form a resin-encapsulated semiconductor device, and a portion indicated by a dashed line indicates After the semiconductor element is mounted and resin-sealed to form a resin-sealed semiconductor device, the lead 4
The cutting portion 5 that cuts the (outer lead portion 4b) is shown.

In the lead frame of this embodiment, as shown in FIG. 1B, the die pad portion 2 is supported by the suspension lead portion 3, and the die pad portion is provided by the depress portion provided on the suspension lead portion 3. Die pad 2 is lead 4
It is upset so as to be disposed above the upper surface.

The lead frame is not a single pattern having the structure shown in FIG. 1, but a plurality of patterns arranged continuously in the left, right, up and down directions.

Next, a resin-sealed semiconductor device using the lead frame of the present embodiment will be described. FIG. 2 shows FIG.
2A is a diagram showing a resin-encapsulated semiconductor device using the lead frame shown in FIG. 2A, FIG. 2A is a perspective plan view showing the internal configuration by a broken line, and FIG. ) DD
It is sectional drawing of one place.

As shown in FIG. 2, a semiconductor element 6 is mounted on the die pad section 2 of the lead frame, and the semiconductor element 6 and the inner lead section 4a of the lead section 4 are electrically connected by a thin metal wire 7. I have. The outer periphery of the semiconductor element 6 and the inner lead portion 4a on the die pad portion 2 is sealed with a sealing resin 8. And the lead part 4
The bottom portion of the (inner lead portion 4 a) is exposed with a standoff from the bottom surface of the sealing resin 8 to form an external terminal 9. Although the outer lead portions 4b are exposed from the side surfaces of the sealing resin 8, they are substantially the same as the side surfaces of the sealing resin 8.

Next, a method of manufacturing the resin-encapsulated semiconductor device of this embodiment will be described.

First, as shown in FIG. 3, a frame frame, a die pad portion 2 having a rectangular shape on which a semiconductor element is mounted, and an upset die pad portion 2 and a corner portion of the die pad portion 2 are placed in the frame frame. A suspension lead supported at its tip and connected to the frame frame at the end, and a beam-shaped beam electrically connected to the mounted semiconductor element by a connecting means such as a thin metal wire when the semiconductor element is mounted. A lead frame having the lead portion 4 is prepared.

Then, as shown in FIG.
The semiconductor element 6 is mounted thereon with an adhesive such as a silver paste and bonded.

Next, as shown in FIG. 5, an electrode pad (not shown) on the surface of the semiconductor element 6 mounted on the die pad portion 2 and an inner lead portion 4a of the lead portion 4 are electrically connected by a thin metal wire 7. Connect to

Next, as shown in FIG. 6, at least the lead portion 4 of the lead frame with the semiconductor element 6 mounted thereon.
The sealing sheet 10 is brought into close contact with the bottom surface of. The sealing sheet 10 is a member for protecting the sealing resin from flowing around the bottom surface of the lead portion 4 and exposing the bottom surface of the lead portion 4.

Next, as shown in FIG. 7, the lead frame is placed in a mold, and the lead 4 is sealed with the sealing sheet 1 by the mold.
A sealing resin 8 made of an epoxy resin is injected in a state where the sealing member 8 is pressed against the upper surface of the die pad portion 2, the semiconductor element 6, and the connection region of the upper surface region of the lead portion 4 and the connection region of the thin metal wire 7. Stop. In FIG.
Shows the state sealed with.

Next, as shown in FIG. 9, the sealing sheet 10 adhered to the bottom surface of the lead portion 4 of the lead frame is removed by peel-off or the like.

Next, as shown in FIG. 10, the lead 5 is cut on the cut portion 5 of the lead portion 4 by the rotating blade 11.

As shown in FIG. 11, the semiconductor element 6 is mounted on the die pad 2 of the lead frame, and the semiconductor element 6 and the inner lead 4a of the lead 4 are electrically connected by the thin metal wire 7. , The enclosing resin 8
And the bottom surface of the lead portion 4 (inner lead portion 4a) is exposed with a standoff from the bottom surface of the sealing resin 8 to form the external terminal 9 and to form the external terminal 9. The outer lead portion 4b is exposed from the side surface, and a resin-sealed semiconductor device having substantially the same surface as the side surface of the sealing resin 8 is obtained.

As described above, when manufacturing a resin-sealed semiconductor device using the lead frame of the present embodiment, in the lead cutting step after resin sealing, the semiconductor device is used for substrate dicing or the like instead of the cutting blade of the mold. Lead portion 4 (cut portion 5) that is cut by cutting with a simple rotating blade 11
, The impact due to the pressing force at the time of cutting is not applied,
The lead portion 4 and the sealing resin 8 in the vicinity of the lead portion 4 can be damaged and the lead can be cut. Therefore, a highly reliable resin-encapsulated semiconductor device can be obtained by eliminating defects and defects in the lead portion and the encapsulation resin portion.

Next, another problem which may occur in the resin-encapsulated semiconductor device obtained by the method of manufacturing a resin-encapsulated semiconductor device of this embodiment will be described.

FIG. 12 is a sectional view showing the problem of the resin-encapsulated semiconductor device of this embodiment. The resin-encapsulated semiconductor device shown in FIG. 12 has the same basic configuration as that of the resin-encapsulated semiconductor device shown in FIG. 2, except that the cutting portion 5 of the lead portion 4 is cut by a rotating blade in the manufacturing process. The lead portion 4 is formed by cutting the lead portion 4 of the cut lead portion 4 with the burrs 12 (metal) on the surface of the outer lead portion 4b of the cut lead portion 4 due to the relationship between the rotating force of the rotating blade and the metal material that is the material of the lead portion 4. Burrs) are formed. When the resin-encapsulated semiconductor device is mounted on a substrate, the burrs 12 may cause a mounting failure or cause a solder bridge at the time of solder bonding. Or the burrs that occurred 1
2 has to be removed. In FIG. 12,
The burrs 12 are shown on the bottom side of the lead 4,
It may also occur on the side surface of the lead portion 4 and on the upper surface side of the lead portion 4.

Normally, factors that cause the burrs 12 include:
The metal material (for example, Cu
Material) is flipped up, and a part of the metal material protrudes in the form of a thin film,
It is considered that the burrs 12 remain on the end surface of the cut lead 4.

Hereinafter, a method of manufacturing a resin-encapsulated semiconductor device according to the present invention will be described with reference to an embodiment in which a flash portion 12 generated mainly on a side surface and a bottom surface side of a lead portion 4 is prevented or generation of the flash portion 12 itself is prevented. Embodiments for solving the problems will be described with reference to the drawings.

FIGS. 13 to 20 are cross-sectional views showing the steps of a method for manufacturing the resin-encapsulated semiconductor device of this embodiment. Note that the lead frame used here has the same configuration as the configuration shown in FIG.

First, as shown in FIG.
In the frame, the die pad 2 having a rectangular shape on which the semiconductor element is mounted, and the upset die pad 2 and the corners of the die pad 2 were supported at the tip end, and the end was connected to the frame. When a semiconductor element is mounted, a lead frame having a suspended lead part and a beam-shaped lead part 4 electrically connected to the mounted semiconductor element by a connecting means such as a thin metal wire is prepared.

Then, as shown in FIG. 14, the semiconductor element 6 is mounted on the die pad portion 2 with an adhesive such as a silver paste and bonded.

Next, as shown in FIG.
The electrode pads (not shown) on the surface of the semiconductor element 6 mounted thereon are electrically connected to the inner lead portions 4 a of the lead portions 4 by the thin metal wires 7.

Next, as shown in FIG. 16, a metal sheet 13 is brought into close contact with at least the bottom surface of the lead portion 4 of the lead frame on which the semiconductor element 6 is mounted. The metal sheet 13 is a member for protecting the sealing resin from wrapping around the bottom surface of the lead portion 4 and exposing the bottom surface of the lead portion 4. To eliminate this, the metal sheet 13 is made of the same material as the lead frame. Therefore, when the lead frame is made of copper (Cu) as a base metal, a copper sheet is adhered. Also, a metal sheet made of a material harder than the lead frame may be used instead of the same material as the lead frame. In this case, a material whose hardness is harder than that of the lead frame and whose expansion coefficient is similar to that of the lead frame is selected. The metal sheet 13 may be adhered to the lead portion 4 by using an adhesive layer on its surface. However, after forming the resin-encapsulated semiconductor device, the metal sheet 13 is easily removed. A metal sheet provided with an easily peelable adhesive layer is used.

Next, as shown in FIG. 17, the lead frame is placed in a mold, and the lead resin 4 is pressed against the metal sheet 13 by the mold to remove the sealing resin 8 made of epoxy resin. Injection is performed to seal the die pad portion 2, the semiconductor element 6, the upper surface region of the lead portion 4, and the connection region between the fine metal wires 7 as the outer periphery of the lead frame. FIG. 18 shows a state in which the outer periphery is sealed with a sealing resin 8.

Next, as shown in FIG.
The lead blade is cut by the rotating blade 11 on the cutting part 5 of the lead part 4 in the state of passing through. In this cutting, the full cutting is performed on the lead portion, and the entire cutting is not performed on the metal sheet 13.

As shown in FIG. 20, the semiconductor element 6 is mounted on the die pad portion 2 of the lead frame by removing the metal sheet adhered to the bottom surface of the lead portion 4 by peeling means such as peel-off. The semiconductor element 6
And the inner lead portion 4a of the lead portion 4 are electrically connected by the thin metal wire 7, the outer periphery is sealed by the sealing resin 8, and the bottom portion of the lead portion 4 (the inner lead portion 4a) is sealed. From the bottom surface of the resin 8, a small amount of protrusion (with a stand-off) is exposed to form an external terminal 9, and the outer lead portion 4 is formed from the side surface of the sealing resin 8.
b is exposed and a resin-sealed semiconductor device having substantially the same surface as the side surface of the sealing resin 8 is obtained.

In the method of manufacturing the resin-encapsulated semiconductor device according to the present embodiment, the metal film is brought into close contact with at least the bottom surface of the lead portion, the resin is sealed in that state, and then the lead is cut. By cutting, it is possible to prevent the occurrence of burrs on the cut end surface of the lead portion because the cutting is performed. In this case, since the material of the metal film is particularly harder than the lead portion (lead frame), no burrs are generated on the end surface of the cut lead portion. In addition, since the metal film is a metal sheet, it can be used in a sealing step, can be sealed on one side with respect to the lead portion, and since the metal sheet is not made of a resin, there is little shrinkage and the sealed resin The formation of a groove at the boundary between the lead and the lead portion can be prevented, and a highly reliable resin-encapsulated semiconductor device can be realized. In addition, since the metal film is made of the same material as the lead frame, the effect of thermal expansion due to heat applied at the time of resin sealing is eliminated, and highly reliable resin sealing and a product can be realized.

As described above, in this embodiment, when the lead is cut to separate the resin-encapsulated semiconductor device, the cut portion of the lead portion on which the tape-shaped metal film is formed is fully cut by the blade. The occurrence of burrs on the cut end face portions of the leads can be prevented. That is, by cutting the lead portion together with the metal film (metal sheet), the degree of splashing of the metal material, which is the material of the lead portion, is reduced by cutting the rotating blade to the vertical position to the end surface of the lead portion, It is possible to suppress the generation of the burrs remaining on the end face.

It is to be noted that optimal values are set as appropriate for the rotation speed of the blade at the time of cutting, the feed speed of the object to be cut, the size of the blade, the material of the blade, and the like.

Further, in the present embodiment, a configuration in which a metal sheet is closely adhered to the bottom surface of the lead is shown as a representative, but a metal film, for example, a metal harder than the lead material, is formed on the upper surface of a portion corresponding to the cut portion of the lead portion of the lead frame. A metal film made of a material harder than the lead material is adhered to the bottom surface of the lead before resin sealing, and the lead portion is formed into a sandwich structure between the metal film and the metal sheet, and the lead is cut and cut. By doing so, it is possible to cut the lead by forming a state where both sides of the lead part are sandwiched between metal materials,
The occurrence of burrs can be further prevented and lead cutting can be performed. In the step of performing a full cut on the lead portion, in addition to one full cut, a plurality of cuts in which the same portion is blade-cut twice or more may be performed.

In this embodiment, one frame is set in the frame.
A package consisting of a unit consisting of two die pads and a plurality of leads arranged in opposition to the lead frame having a plurality of units in its area is resin-sealed for each unit to form a package. Then, the example in which the lead portion exposed between the units is cut by the cut portion is shown. However, as shown in the present embodiment, the lead portion is gradually cut, and the cut is performed in the shape of the blade. ,width,
By means of performing lead cutting by changing the direction of the surface to be cut, all the units in the lead frame are comprehensively resin-sealed as a one-piece molding, and the upper surface of the lead portion between each unit, that is, the lead between each unit, Even when the sealing resin is formed at the cut portion of the portion, the same operation and effect can be obtained.

In the present embodiment, a semiconductor element is mounted on a lead frame as a representative and connected with a thin metal wire. Then, a metal film is formed on the bottom surface of the lead portion before resin sealing, and the resin sealing is performed. Although the example of cutting the lead together with the metal film was shown, the formation of the metal film may be performed only in the step before cutting the lead, and a sealing sheet such as a resin tape is adhered to the bottom surface of the lead portion before resin sealing. Then, the sealing sheet is removed, the sealing sheet is removed, a metal film is separately formed on the bottom surface of the lead portion, and the lead is cut off.

[0064]

As described above, in the method of manufacturing a resin-encapsulated semiconductor device of the present invention, in the lead cutting step after resin encapsulation, a rotary blade used for substrate dicing or the like is used instead of the cutting blade of the mold. By cutting and cutting, an impact due to the pressing force at the time of cutting is not applied to the lead portion to be cut, and the lead portion and the sealing resin in the vicinity of the lead portion are eliminated to cut the lead. be able to. Therefore, a highly reliable resin-encapsulated semiconductor device can be obtained by eliminating defects and defects in the lead portion and the encapsulation resin portion.

When separating the resin-encapsulated semiconductor device by cutting the lead from the lead frame after resin encapsulation, the metal film is brought into close contact with at least the bottom surface of the lead portion.
Since resin sealing is performed in that state and then lead cutting, cutting the blade together with the metal film, and cutting it together, can prevent generation of burrs on the cut end surface of the lead, and provide a highly reliable resin. A sealed semiconductor device can be obtained.

[Brief description of the drawings]

FIG. 1 is a view showing a lead frame according to an embodiment of the present invention;

FIG. 2 is a diagram showing a resin-sealed semiconductor device according to one embodiment of the present invention;

FIG. 3 is a cross-sectional view illustrating a method for manufacturing a resin-sealed semiconductor device according to one embodiment of the present invention.

FIG. 4 is a cross-sectional view illustrating a method for manufacturing a resin-sealed semiconductor device according to one embodiment of the present invention.

FIG. 5 is a sectional view showing the method for manufacturing the resin-sealed semiconductor device according to the embodiment of the present invention;

FIG. 6 is a sectional view showing the method of manufacturing the resin-sealed semiconductor device according to one embodiment of the present invention;

FIG. 7 is a sectional view showing the method of manufacturing the resin-sealed semiconductor device according to one embodiment of the present invention;

FIG. 8 is a sectional view showing the method for manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 9 is a sectional view showing the method of manufacturing the resin-sealed semiconductor device according to one embodiment of the present invention;

FIG. 10 is a sectional view showing the method of manufacturing the resin-sealed semiconductor device according to one embodiment of the present invention;

FIG. 11 is a sectional view showing the method of manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 12 is a sectional view showing a problem of the resin-sealed semiconductor device according to the embodiment of the present invention;

FIG. 13 is a sectional view showing the method of manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 14 is a sectional view showing the method of manufacturing the resin-sealed semiconductor device according to one embodiment of the present invention;

FIG. 15 is a sectional view showing the method of manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 16 is a sectional view showing the method of manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 17 is a sectional view showing the method of manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 18 is a sectional view showing the method of manufacturing the resin-sealed semiconductor device according to one embodiment of the present invention;

FIG. 19 is a sectional view showing the method of manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 20 is a sectional view showing the method of manufacturing the resin-encapsulated semiconductor device according to one embodiment of the present invention;

FIG. 21 shows a conventional lead frame.

FIG. 22 shows a conventional resin-encapsulated semiconductor device.

FIG. 23 is a sectional view showing a method for manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 24 is a sectional view showing a method of manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 25 is a sectional view showing a method for manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 26 is a sectional view showing a method of manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 27 is a sectional view showing a method for manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 28 is a sectional view showing a method of manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 29 is a cross-sectional view showing a method for manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 30 is a sectional view showing a method for manufacturing a conventional resin-encapsulated semiconductor device.

FIG. 31 is a sectional view showing a method of manufacturing a conventional resin-encapsulated semiconductor device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frame frame 2 Die pad part 3 Suspended lead part 4 Lead part 5 Cutting part 6 Semiconductor element 7 Thin metal wire 8 Sealing resin 9 External terminal 10 Sealing sheet 11 Rotating blade 12 Flash part 13 Metal sheet 101 Frame frame 102 Die pad part 103 Hanging Lead part 104 Lead part 105 Semiconductor element 106 Thin metal wire 107 Sealing resin 108 External terminal 109 Sealing sheet 110 Cutting part 111 Cutting blade

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Osamu Adachi 1-1, Yukicho, Takatsuki-shi, Osaka Matsushita Electronics Co., Ltd. (72) Katsuyoshi Utsumi 1-1, Yukicho, Takatsuki-shi, Osaka Matsushita Electronics Incorporated (72) Inventor Masanori Minao 1-1, Sachimachi, Takatsuki-shi, Osaka Matsushita Electronics Co., Ltd.

Claims (5)

[Claims] 1. A frame main body made of a metal plate, a die pad portion for mounting a semiconductor element disposed in a substantially central region of the frame main body, and the die pad portion is supported at a front end portion, and the frame is supported at the other end portion. Suspended lead portion connected to the frame, at least the tip portion extends toward the die pad portion,
A step of preparing a lead frame including a lead portion having the other end connected to the frame frame, and a cut portion provided near a region of the lead portion connected to the frame frame; and a die pad of the prepared lead frame. Mounting a semiconductor element on the die pad portion, connecting the electrode pads on the main surface of the semiconductor element mounted on the die pad portion, and connecting each upper surface of the lead portion of the lead frame with a thin metal wire; A step of forming a metal film on each bottom surface of at least the lead portion on the back surface side of the lead frame, and applying a pressing force to at least an end of the lead portion, and pressing the bottom surface of the lead portion against the metal film, The semiconductor element, the die pad portion, the thin metal wire, and the region where the bottom surface of the lead portion is connected to the frame of the lead portion as the upper surface side of the lead frame. A step of resin-sealing a region other than the cut portion provided in the vicinity with a sealing resin, and cutting the upper surface of the cut portion of the lead with a blade, and cutting together with the metal film formed on the lower surface of the cut portion Cutting the portion to separate the resin-sealed semiconductor device; and removing the metal film formed on the bottom surface of the separated resin-sealed semiconductor device to obtain a resin-sealed semiconductor device. A method for manufacturing a resin-encapsulated semiconductor device, comprising: 2. A frame main body made of a metal plate, a die pad portion for mounting a semiconductor element disposed in a substantially central region of the frame main body, a tip end portion supporting the die pad portion, and the other end portion supporting the frame. Suspended lead portion connected to the frame, at least the tip portion extends toward the die pad portion,
A step of preparing a lead frame including a lead portion having the other end connected to the frame frame, and a cut portion provided near a region of the lead portion connected to the frame frame; and a die pad of the prepared lead frame. Mounting a semiconductor element on the die pad portion, connecting the electrode pads on the main surface of the semiconductor element mounted on the die pad portion, and connecting each upper surface of the lead portion of the lead frame with a thin metal wire; A step of bringing a sealing sheet into close contact with at least each bottom surface of the lead portion on the back surface side of the lead frame, and a state in which a pressing force is applied to at least an end portion of the lead portion and the bottom surface of the lead portion is pressed against the sealing sheet The semiconductor element, the die pad portion, the thin metal wire, and the bottom surface of the lead portion and the frame frame of the lead portion as the upper surface side of the lead frame. A step of resin-sealing a region except a cut portion provided in the vicinity of the continuous region with a sealing resin, a step of removing the sealing sheet, and forming a metal on at least each bottom surface of the lead portion on the back surface side of the lead frame. A step of forming a film, and a step of performing cutting with a blade on the upper surface of the cut portion of the lead, and cutting the cut portion together with the metal film formed on the lower surface of the cut portion to separate the resin-encapsulated semiconductor device. And a step of removing the metal film formed on the bottom surface of the separated resin-encapsulated semiconductor device to obtain a resin-encapsulated semiconductor device. 3. The step of forming a metal film on at least each bottom surface of the lead portion on the back side of the lead frame is a step of forming a metal film by closely attaching a metal sheet as the metal film. A method for manufacturing a resin-encapsulated semiconductor device according to claim 1. 4. The method according to claim 1, wherein in the step of forming a metal film on at least each bottom surface of the lead portion on the back surface side of the lead frame, the metal film is formed of the same material as the lead frame. Item 3. A method for manufacturing a resin-sealed semiconductor device according to any one of Items 2. 5. The step of forming a metal film on at least each bottom surface of the lead portion on the back surface side of the lead frame, wherein the metal film is formed of a metal film made of a metal harder than the material of the lead frame. 3. The method for manufacturing a resin-encapsulated semiconductor device according to claim 1 or 2.