JPH06350009A - Manufacture of semiconductor device and lead frame - Google Patents

Abstract

PURPOSE:To provide a manufacturing method of a semiconductor device having excellent positioning accuracy and the high product yield rate without deviation at the time of bonding an inner lead and the terminal of a semiconductor chip in the manufacturing method of the semiconductor device based on a lead on- chip method. CONSTITUTION:A lead frame 4, wherein the tip of each inner lead 4b extends to a terminal 2A of a semiconductor chip 2, is formed of a metal plate. A linking part 4i is provided between the respective inner leads 4b at the outside of the outer surface part of the semiconductor chip 2 mounted at this time. Then, the inner lead 4b and the terminal 2A are bonded with a gold bump 7. Thereafter, the linking part 4i of the inner leads 4b is cut with a laser beam. Then, the semiconductor chip 2 and the inner leads 4b are sealed as a unitary body with a mold part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device, and more particularly to a QF having outer leads in four directions.
A method of manufacturing a semiconductor device having a configuration of a plastic flat package called P (Quad Flat Package),
And a lead frame used in the process.

[0002]

2. Description of the Related Art QF with outer leads in four directions
A semiconductor device having a structure of a plastic flat package called P (Quad Flat Package) has a semiconductor chip mounted on a metal lead frame, and each lead (inner lead) and a terminal of the semiconductor chip are electrically connected. The inner lead portions of these lead frames and the semiconductor chip are sealed by resin molding. In recent years, there has been a strong demand for high-density mounting and high integration of semiconductor chips, and in order to meet this demand, lead frames on which semiconductor chips are mounted have been developed with fine and highly precise dimensions and shapes. Is coming.
In particular, the number of pins of the lead frame is being emphasized, and along with this, a processing technique such as laser processing has been developed which is capable of finely processing the pitch of the inner lead tips narrowly.

In such a semiconductor device, the connection between each inner lead and the terminal of the semiconductor chip is often wire-bonded by a gold wire or the like, and the minimum pitch between the terminals of the semiconductor chip at that time is about 110 μm. .
On the other hand, in the one disclosed in Japanese Patent Laid-Open No. 1-128893, the terminals of the mounted semiconductor chip and the inner leads of the lead frame are directly connected by bumps such as solder.

On the other hand, as a plastic flat package that does not use a lead frame, TAB (Tap Automate) is used.
d Bonding) method. This is, for example, Japanese Patent Laid-Open No. 2-6
As described in Japanese Patent No. 5166, etc., a Cu foil lead is formed on a polyimide film, the lead and a terminal of a semiconductor chip are directly bonded, and these are integrally sealed with a resin mold. It is possible to form a fine pattern and to narrow the pitch between leads to about 70 μm (narrower pitch).

Further, a lead-on-chip system (hereinafter referred to as LOC system) of a type in which the TAB system is applied to the system described in Japanese Patent Laid-Open No. 1-128893.
A method called is known. This uses a lead frame and extends the tips of the inner leads, which are finely and narrowly processed, to the terminals of the semiconductor chip, and the tips of the inner leads and the terminals of the semiconductor chip are directly connected by gold bumps or the like. It is a method of joining. According to this method, in a semiconductor device using a lead frame having a high strength to some extent, miniaturization and narrow pitch can be realized, and the semiconductor device can be miniaturized, have high performance, and have a large number of pins. There are many advantages. That is, unlike the case of wire bonding, there is no concern that the gold wire will be broken, and there is no need to secure a space for bonding, so that the pitch can be made extremely fine and narrow. Further, since the tips of the inner leads and the terminals of the semiconductor chip are firmly and surely joined, the joining reliability is high. Laser cutting or the like can be used as a method of processing the tips of the inner leads into a fine and narrow pitch.

[0006]

In the LOC method, the tips of the inner leads joined to the terminals of the semiconductor chip are extremely fine and have a narrow pitch. For example, the width of the inner leads is shorter than the plate thickness. In such a case, the rigidity of that portion is insufficient, the portion is easily deformed by a slight external impact, and it is very likely to be displaced at the time of joining with the terminal of the semiconductor chip. Moreover, this joining portion requires high dimensional accuracy and positioning accuracy, but its positioning is extremely difficult due to the fineness and narrow pitch, and as described above, the inner lead is not deformed or displaced during joining. If it occurs, the dimensional accuracy and the positioning accuracy will be significantly reduced.

For example, when a low melting point metal such as a gold bump is used for joining the two, if the tip of the inner lead is superposed on the gold bump, this portion will ride on the convex gold bump surface. Due to the low rigidity, it becomes very difficult to perform alignment and superposition with high accuracy.

An object of the present invention is to provide a method of manufacturing a semiconductor device by the LOC method, which does not shift when the inner lead and the terminal of the semiconductor chip are joined, has good positioning accuracy, and has a high product yield. And to provide a lead frame used in the process.

[0009]

In order to solve the above-mentioned problems, according to the present invention, terminals of a semiconductor chip are electrically connected to inner leads of a lead frame, and the inner leads of the semiconductor chip and the lead frame are formed in a molding portion. In the method of manufacturing a semiconductor device integrally sealed with a semiconductor device, a lead frame is formed from a metal plate in which the tips of the inner leads extend to the terminal portion of the semiconductor chip, and at that time, each inner portion is provided outside the outer peripheral portion of the semiconductor chip. A connecting portion is provided between the leads, then the inner lead and the terminal of the semiconductor chip are joined, the connecting portion of the inner lead is cut by a laser beam, and then the semiconductor chip and the lead frame are formed into a molding portion. Provided is a method for manufacturing a semiconductor device, which comprises integrally sealing

In the above method of manufacturing a semiconductor device, preferably, when the inner lead and the terminal of the semiconductor chip are joined, a melting point lower than that of the lead frame is provided between the terminal of the semiconductor chip and the vicinity of the tip of the inner lead. This metal having a low melting point is used for joining.

Further, preferably, after forming the lead frame from a metal plate and before joining each inner lead and a terminal of the semiconductor chip, an inner lead is formed on an outer peripheral portion of the connecting portion of the inner lead. Affix a reinforcing tape to fix the mutual position of each other.

In order to solve the above-mentioned object, according to the present invention, a plurality of inner leads joined to each terminal of a semiconductor chip and outer leads continuous to the outside of the inner leads are provided, and the center lead is provided. In the lead frame on which the semiconductor chip is mounted, the inner lead has a length such that its tip extends to the terminal portion of the semiconductor chip, and each inner lead is outside the outer peripheral portion of the mounted semiconductor chip. A lead frame is provided, which is characterized in that a connecting portion is provided between the leads.

[0013]

In the present invention constructed as described above, the LO
A semiconductor device is manufactured by the C method. That is, the lead frame is formed by cutting out the metal plate so that the tips of the fine and narrow inner leads extend to the terminals of the semiconductor chip, and the tips of the inner leads and the terminals of the semiconductor chip are directly joined. It At this time, in the lead frame, a connecting portion for connecting the inner leads is provided outside the outer peripheral portion of the mounted semiconductor chip.

By providing the connecting portion as described above,
Since the mutual interval near the tip portion of the inner lead joined to the terminal of the semiconductor chip is fixed and constrained, the terminal of the semiconductor chip and the tip portion of the inner lead can be easily aligned and superposed, and the joint portion Dimensional accuracy and positioning accuracy are improved. Further, since the rigidity near the tip of the inner lead is improved, the inner lead is not deformed or displaced by an external impact.

After the above-mentioned joining work, the connecting portion connecting the inner leads is cut by laser processing and separated into individual inner leads. Since this laser processing is a method of rapidly heating locally and melting and cutting, it is processed with high dimensional accuracy. Further, since the connecting portion exists outside the outer peripheral portion of the semiconductor chip, the semiconductor chip is not damaged by the cutting at the time of this cutting. And
The semiconductor chip and the lead frame are integrally sealed by the mold part.

Further, according to the present invention, the tips of the inner leads extended to the vicinity of the terminals of the semiconductor chip are directly joined to the terminals, and the inner leads are connected to each other before the joining. The terminals of the chip can be connected at one time, which shortens the processing time. Also,
Since wire bonding is not used, there is no need to secure a space for bonding and it is possible to make it extremely fine and narrow pitch.Also, even if the lead pitch is made finer, there is no breakage of the gold wire during wire bonding or resin molding. The problem of contact between gold wires does not occur.

Further, when the inner lead and the terminal of the semiconductor chip are joined as described above, if a metal having a melting point lower than that of the lead frame such as a gold bump is interposed between the inner lead and the terminal of the semiconductor chip, the joining is surely performed. It becomes possible to do.

After forming the lead frame from a metal plate and before joining the leads and the terminals of the semiconductor chip, a reinforcing tape is attached to the outer peripheral portion of the connecting portion of the inner lead, whereby The mutual position of the leads is further fixed and restrained.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method of manufacturing a semiconductor device according to the present invention will be described with reference to FIGS. FIG. 1 shows a lead frame used in the method of manufacturing a semiconductor device according to this embodiment. In FIG. 1, a die pad 4 a on which a semiconductor chip (not shown) is mounted is provided in the central portion of the lead frame 4.
A large number of inner leads 4b are provided so as to surround a, and outer leads 4c continuous with these inner leads 4b are arranged. The inner lead 4b and the outer lead 4c adjacent to each other are supported by the dam bar 4d so as to be connected to each other. Further, a cutout portion 4f is provided around the die pad 4a except for the arm 4e, and the inner lead 4b is separated from the die pad 4a by the cutout portion 4f.
The inner leads 4b adjacent to each other are each divided by the cutout portion 4f. Further, an outer frame portion 4g for fixing each portion is provided on the outer peripheral portion of the lead frame 4,
The outer frame portion 4g is provided with a positioning hole 4h for positioning when the terminals of the semiconductor chip and the inner leads 4b are connected. The dam bar 4d has a role of blocking the resin when the semiconductor chip is molded and a role of reinforcing the inner leads 4b and the outer leads 4c, and is removed after the molding.

Further, the inner leads 4b are extended so as to converge toward the die pad 4a, and the gap between the adjacent inner leads 4a is extremely fine, especially the gap in the inner portion is narrower than the plate thickness (for example, a very fine structure). , The thickness of the metal plate is 0.
In the case of 15 mm, it is about 0.07 mm), and the processing of this portion is the most strict in dimensional accuracy and cleanliness in the processing of the lead frame. The inner lead 4b has a length that extends to a terminal portion on the semiconductor chip when the semiconductor chip (see FIG. 5) is mounted on the die pad 4a, and connects the inner leads outside the outer peripheral portion of the semiconductor chip. A section 4i is provided. Incidentally, as a processing method for forming such a lead frame from a metal plate, there are conventional press processing, etching processing and the like, but laser processing is particularly suitable as a processing method for the fine inner lead 4b having a narrow pitch. ing.

Next, the structure of a semiconductor device using the above lead frame will be described with reference to FIG. In the semiconductor device 1 shown in FIG. 2, the semiconductor chip 2 is mounted on the die pad 4a by being bonded with a thermosetting resin 6, and the inner leads 4b and the terminals of the semiconductor chip 2 are electrically connected by the gold bumps 7. A portion that is connected and includes the semiconductor chip 2 and the inner lead 4b is sealed with a resin mold 5. The outer leads 4c are individually divided by cutting the dam bars 4d (see FIG. 1), and are further bent and formed outside the resin mold 5. The bent portion of the outer lead 4c is connected to the circuit pattern of the printed circuit board when the semiconductor device 1 is mounted on the printed circuit board later.
Instead of the gold bump 7, a metal bump having a melting point lower than that of the lead frame such as a solder bump or a tin bump may be used.

Next, one embodiment of the method for manufacturing the above-mentioned semiconductor device 1 will be described with reference to FIGS. First, in step 100 of FIG. 3, a metal plate such as steel, copper alloy, 42 alloy, and Kovar is placed on a leveler and processed into a predetermined thickness. Next, in step 101, the metal plate is processed to form a lead frame as shown in FIG.
At this time, laser processing is particularly suitable for processing the fine and narrow-pitch inner leads 4b. Next, solder plating is applied to the entire surface of the metal plate processed as described above.

Next, in step 102, a thermosetting adhesive 6 is applied to the circuit forming surface of the semiconductor chip 2 and gold bumps 7 are formed on the terminals of the semiconductor chip 2. In addition, before applying the thermosetting adhesive, the semiconductor chip 2
It is preferable to form an electrically insulating protective film on the circuit formation surface.

Next, in step 103, the semiconductor chip 2 is mounted on the die pad 4a of the lead frame 4 formed as described above. At this time, the semiconductor chip 2 is arranged such that the circuit forming surface coated with the adhesive faces the die pad 4a, and the tips of the inner leads 4a are aligned with the gold bumps 7 arranged at the terminals of the semiconductor chip 2. The semiconductor chip is mounted and positioned with the inner leads 4b and the die pad 4a kept in the same plane. Further, at this time, since the inner leads 4b are connected by the connecting portions 4i, the mutual intervals of the inner leads 4b are fixed and restrained, and the alignment and the superposition with the terminals of the semiconductor chip 2 can be easily performed.

Next, at step 104, heat and pressure are applied by pressing a trowel heated to a high temperature from above the die pad 4a to cure the thermosetting adhesive to bond the semiconductor chip 2 and the die pad 4a. Similarly, a trowel that has been heated to a high temperature is also pressed against the tips of the inner leads 4 to apply heat and pressure to electrically join the tips of the inner leads 4b and the terminals of the semiconductor chip 2 via gold bumps. . In this case, the two trowels are pressed together so that the semiconductor chip 2 and the die pad 4a are joined together and the tips of the inner leads 4b and the terminals of the semiconductor chip 2 are joined at the same time. FIG. 4 shows how the tips of the inner leads 4b and the terminals of the semiconductor chip 2 are joined at this time.

As shown in FIGS. 4A to 4C, the tip of the inner lead 4b and the terminal of the semiconductor chip 2 are bonded to each other by
The inner lead 4b is connected with the connecting portion 4i. That is, each inner lead 4 is formed on each terminal 2A of the semiconductor chip 2 as described in step 103 above.
b is positioned, and both are directly bonded via the gold bumps 7 as they are. In addition, since the inner leads 4b are connected by the connecting portions 4i, the rigidity of this portion is improved, and the inner leads 4b are not deformed or displaced by an external impact during or after the joining. Further, the connecting portion 4i indicated by hatching in FIG. 4 is cut off by laser processing after the joining work. Then, as shown in FIG. 5, the connecting portions 4i are sequentially cut off, and finally all the connecting portions 4i are cut off to separate the inner leads 4b individually. Since this laser processing is a method of locally rapidly heating and melting cutting,
Processed with high dimensional accuracy. Further, since the connecting portion 4i exists outside the outer peripheral portion of the semiconductor chip 2, the semiconductor chip 2 is not damaged during the cutting.

Next, in step 105, the semiconductor chip 2, the die pad 4a bonded as described above, and the inner leads 4b separated after bonding are integrally sealed with a resin mold 5.

Next, at step 106, the dam bar 4
The semiconductor chip 2 and the lead frame 4 are cut by cutting laser beam d and cutting the outer frame portion 4g by pressing or the like.
Then, in step 107, the outer lead 4c is bent and molded, the product number, the manufacturing number, etc. are marked, and finally in step 108, the product is inspected, packaged, and shipped.

In the present embodiment as described above, since the connecting portion 4i for connecting the inner leads 4b is provided outside the outer peripheral portion of the semiconductor chip 2, the inner leads 4 are formed.
Since the mutual distance near the tip portion of b is fixed and constrained, the terminal 2A of the semiconductor chip 2 and the tip portion of the inner lead 4b can be easily aligned and superposed. Therefore, the dimensional accuracy and the positioning accuracy of the joint portion can be improved, and the rigidity in the vicinity of the tip portion of the inner lead 4b can be improved, so that the joint portion will not be deformed or displaced due to external impact.

After the joining operation, the connecting portion 4i can be cut off by laser processing to be cut into individual inner leads 4b. Since this laser processing is a method of rapidly heating locally and melting and cutting, it is possible to perform processing with high dimensional accuracy. Further, since the connecting portion 4i exists outside the outer peripheral portion of the semiconductor chip 2, the semiconductor chip 2 is not damaged by the cutting at the time of the cutting.

The tip of the inner lead 4b extended to the vicinity of the terminal of the semiconductor chip 2 is directly joined to the terminal,
Moreover, since the inner leads are connected to each other before joining, the individual inner leads 4b and the terminals 2A of the semiconductor chip 2 can be collectively connected, and the processing time is shortened. In addition, since wire bonding is not used, it is not necessary to secure a space for bonding and it is possible to make a very fine and narrow pitch, and even if the lead pitch is made finer, there is a break in the gold wire at the time of wire bonding,
The problem of contact between the gold wires during resin molding does not occur.

In this embodiment, a low melting point metal such as a gold bump was used at the time of joining, but without using this, the inner lead 4b and the terminal 2A of the semiconductor chip 2 are brought into direct contact with each other and the laser is applied to this portion. Bonding can also be performed by converging a light or electron beam and heating locally and rapidly.

Another embodiment of the method of manufacturing a semiconductor device according to the present invention will be described with reference to FIGS. First, in step 200 of FIG. 6, a metal plate of steel, copper alloy, 42 alloy, Kovar or the like is placed on a leveler and processed into a predetermined thickness, as in FIG. Next, in step 201, the metal plate is processed to form a lead frame as shown in FIG. At this time, laser processing is particularly suitable for processing the fine inner lead 4b having a narrow pitch. Next, solder plating is applied to the entire surface of the metal plate processed as described above.

Next, at step 202, as shown in FIG. 7, the reinforcing tape 8 is attached to the outer peripheral portion of the connecting portion 4i of the lead frame 4. The reinforcing tape 8 reliably fixes and constrains the mutual positions of the inner leads 4b and prevents the displacement. In addition, step 206 described later
When the semiconductor chip 2, the die pad 4a, and the inner lead 4b are integrally sealed with the resin mold 5, the intermediate portions of the inner lead 4b are prevented from contacting each other.

Next, in step 203, the thermosetting adhesive 6 is applied to the circuit forming surface of the semiconductor chip 2 and the gold bumps 7 are formed on the terminals of the semiconductor chip 2.

Next, at step 204, the semiconductor chip 2 is mounted on the die pad 4a of the metal plate formed as described above. Also at this time, the semiconductor chip 2 is arranged so that the circuit forming surface coated with the adhesive faces the die pad 4a, and the tips of the inner leads 4a are aligned with the gold bumps 7 arranged on the terminals of the semiconductor chip 2. Since the inner leads 4b are connected by the connecting portions 4i, the mutual intervals of the inner leads 4b are fixed and constrained, and the alignment and superposition with the terminals of the semiconductor chip 2 can be easily performed.

Next, at step 205, the thermosetting adhesive is hardened to bond the semiconductor chip 2 and the die pad 4a, and the tips of the inner leads 4b and the terminals of the semiconductor chip 2 are electrically connected via gold bumps. To join. This joining is also performed while the inner leads 4b are still connected by the connecting portion 4i, so that the inner leads 4b are not deformed or displaced due to an external impact during and after the joining. And
The connecting portion 4i is cut off by laser processing after the above-mentioned joining work, and the inner leads 4b are individually cut off.

Next, in step 206, the semiconductor chip 2, the die pad 4a joined as described above, and the inner leads 4b which have been individually separated after joining are integrally sealed with a resin mold 5. Subsequently, the four corner portions of the lead frame 4 outside the resin mold 5 are cut by pressing or the like. This part to be cut is an unnecessary part in the final product, and after cutting, the part shown in FIG.
As shown in (a), the outer sides of the outer leads 4c are connected by the outer frame portion 4g.

Next, in step 207, the outer leads 4c are bent and formed based on the final shape of the outer leads 4c, as shown in FIG. 8B, while the outer leads 4c are still connected by the outer frame portion 4g. However, in the cross-sectional view shown in FIG. 8B, the structure inside the resin mold 5 is omitted.
After that, the outer frame portion 4g outside the outer leads 4c is cut by pressing or the like. After that, the dam bar 4d is cut by laser processing.

By the way, the semiconductor device manufactured in this embodiment is called a surface mount type semiconductor device which can be directly mounted and bonded on a printed wiring board. Lead)
Has a protruding structure. Therefore, as described above, the tips of the outer leads are appropriately bent so that they can be easily mounted on the printed wiring board. The pitch of the outer leads tends to be narrower like the inner leads for downsizing, high performance, and high pin count of semiconductor devices, and semiconductor devices with a pitch of 0.3 mm or less have been developed. Is the current situation. In order to reliably and reliably bond the narrow pitch outer leads to the wiring pattern on the printed wiring board, the pitch accuracy and bending accuracy of the outer leads must also be strictly controlled.

In the present embodiment, as described above, the outer leads 4c are bent and formed based on the shape of the outer leads 4c while being connected to each other by the outer frame portion 4g, and thereafter the outer leads 4c are formed outside the outer leads 4c. Since the outer frame portion 4g is cut by pressing or the like, even if the outer leads 4c have a narrow pitch, the mutual intervals of the outer leads 4c are fixed and restrained. Therefore, the pitch accuracy and the bending accuracy are good, and the mounting on the wiring pattern on the printed wiring board can be performed reliably and with high reliability.

Next, in step 208, the connection between the semiconductor chip 2 and the lead frame 4 is inspected, the product number, the manufacturing number, etc. are marked, and finally in step 209, the product is inspected, packaged and shipped.

According to the present embodiment as described above, not only the same effect as the embodiment of FIGS. 1 to 5 can be obtained, but also the reinforcing tape 8 is provided on the outer peripheral portion of the connecting portion 4i of the lead frame 4. Since they are attached to each other, the mutual positions of the inner leads 4b are securely fixed and restrained to prevent the displacement, and it is possible to prevent the intermediate portions of the inner leads 4b from contacting each other when they are integrally sealed with the resin mold 5.

Further, each outer lead 4c has an outer frame portion 4g.
Since the outer frame portion 4g is cut after being bent and formed in a state where the outer leads 4c are connected to each other, the mutual interval of the outer leads 4c is fixed and restrained. Therefore, the pitch accuracy and the bending accuracy are good, and the mounting on the wiring pattern on the printed wiring board can be performed reliably and with high reliability.

Although the outer frame portion 4g of the lead frame 4 is used for fixing and restraining the mutual distance between the outer leads 4c in the above embodiment, the outer lead portion 4g is not used but the outer lead 4c is separately provided. You may provide a connection part.

Still another embodiment of the method of manufacturing a semiconductor device according to the present invention will be described with reference to FIG.
In this embodiment, the cutting of the dam bar 4d is performed by cutting the outer lead 4c.
Unlike the embodiment shown in FIG. 6 which is performed after the bending and shaping of the outer frame portion 4g and the bending of the outer lead 4c, the dam bar 4d is cut before the bending and shaping of the outer lead 4c.

That is, in step 206a, the four corners outside the resin mold 5 are cut by press working or the like, and then the dam bar 4d is cut by laser working or the like. Therefore, in the next step 207a, only the bending of the outer lead 4c and the cutting of the outer frame portion 4g are performed. Other than the above, it is the same as the embodiment of FIG.

According to this embodiment as described above, the same effects as those of the embodiments of FIGS. 6 to 8 can be obtained.

[0049]

According to the present invention, since the connecting portion for connecting the inner leads is provided, the mutual interval of the inner leads is fixed and restrained, and the alignment and the superposition with the semiconductor chip can be easily performed. it can. Therefore, it is possible to improve the dimensional accuracy and the positioning accuracy of this joint portion,
Since the rigidity near the tip of the inner lead can be improved,
It does not deform or shift even when subjected to external impact.

Further, since the connecting portion is provided outside the outer peripheral portion of the semiconductor chip, the semiconductor chip is not damaged when the connecting portion is cut.

Further, since the tips of the inner leads extended to the vicinity of the terminals of the semiconductor chip are directly joined to the terminals, and the inner leads are connected to each other before the joining,
Individual inner leads and the terminals can be collectively connected, and the processing time is shortened. Further, since wire bonding is not used, it is not necessary to secure a bonding space, and it is possible to make the pitch extremely fine and to have a narrow pitch, and there is no problem such as breaking of the gold wire or contact between the gold wires during resin molding.

Further, since the reinforcing tape is attached to the outer peripheral portion of the connecting portion, the mutual positions of the inner leads are securely fixed and restrained to prevent the displacement, and the inner leads come into contact with each other when sealing with the resin mold. Is prevented.

Further, since the outer leads are bent and formed in a state of being connected to each other by the outer frame portion, and then the outer frame portion is cut, the mutual intervals of the outer leads are fixed and restrained. Therefore, the pitch accuracy and bending accuracy are good,
Mounting to the wiring pattern on the printed wiring board can be performed reliably and with high reliability.

[Brief description of drawings]

FIG. 1 is a diagram showing a lead frame used in a method of manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a semiconductor device using the lead frame of FIG.

FIG. 3 is a flowchart showing manufacturing steps of the semiconductor device shown in FIG.

FIG. 4 is a diagram showing how the tips of the inner leads are joined to the terminals of the semiconductor chip.

FIG. 5 is a view showing a state in which the connecting portion is being cut off in order.

FIG. 6 is a flowchart showing manufacturing steps of a semiconductor device according to another embodiment of the present invention.

FIG. 7 is a diagram showing a state in which a reinforcing tape is attached to a portion on the outer periphery of the lead frame with respect to the connecting portion.

FIG. 8A is a view showing a state in which four corner portions of the lead frame outside the resin mold are cut, and FIG. 8B is a view of bending the outer lead with the outer frame portion connected. It is sectional drawing which shows the state.

FIG. 9 is a flowchart showing manufacturing steps of a semiconductor device according to still another embodiment of the present invention.

[Explanation of symbols]

 1 semiconductor device 2 semiconductor chip 2A terminal 4 lead frame 4b inner lead 4c outer lead 4d dam bar 4g outer frame part 4i connecting part 5 resin mold 7 gold bump 8 reinforcing tape

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeyuki Sakurai 650 Kazutachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd.Tsuchiura factory (72) Inventor Yoshiya Nagano 650 Kintate-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co. Ceremony Company Tsuchiura Factory

Claims (4)

[Claims] 1. A method of manufacturing a semiconductor device, wherein terminals of a semiconductor chip are electrically connected to inner leads of a lead frame, and the inner leads of the semiconductor chip and the lead frame are integrally sealed by a mold part. A lead frame whose tip extends to the terminal portion of the semiconductor chip is formed of a metal plate, and a connecting portion is provided between the inner leads outside the outer peripheral portion of the semiconductor chip, and then the inner lead and the semiconductor are provided. A semiconductor device, characterized in that the terminals of a chip are joined together, then the connecting portion of the inner lead is cut by a laser beam, and then the semiconductor chip and the lead frame are integrally sealed by a molding portion. Production method. 2. The method of manufacturing a semiconductor device according to claim 1, wherein when the inner lead and the terminal of the semiconductor chip are joined, the lead frame is provided between the terminal of the semiconductor chip and the vicinity of the tip of the inner lead. Also, a method of manufacturing a semiconductor device, characterized in that a metal having a low melting point is interposed and bonding is performed by the metal having a low melting point. 3. The method of manufacturing a semiconductor device according to claim 1, wherein after forming the lead frame from a metal plate and before joining each inner lead and a terminal of the semiconductor chip, A method of manufacturing a semiconductor device, further comprising affixing a reinforcing tape for fixing mutual positions of inner leads to an outer peripheral portion of the connecting portion. 4. A lead frame having a large number of inner leads joined to respective terminals of a semiconductor chip, and outer leads continuous to the outside of the inner leads, and having the semiconductor chip mounted in a central portion, The inner lead has a length that extends to the terminal portion of the semiconductor chip, and a connecting portion is provided between the inner leads outside the outer peripheral portion of the semiconductor chip to be mounted. Lead frame to