JPH09115951A - Semiconductor device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve improved package characteristics in all characteristic surfaces such as packaging characteristic for a semiconductor device with a structure which is similar to QTP and its manufacturing method. SOLUTION: In a semiconductor device which is surface-mounted on a packaging substrate, a lead member 4 is constituted of a frame-shaped base member 6 for supporting a resin package 5 on the packaging substrate and a foil-shaped lead 7 which is protected by the frame-shaped base member 6 while being provided inside the frame-shaped base member 6. Also, the foil-shaped lead 7 is curved and protrudes downward from the frame-shaped base member 6 while it is not placed on the packaging substrate yet and at the same time the base member 6 and the foil-shaped lead 7 are flush with the packaging surface since the foil-shaped lead 7 is flexibly deformed in packaged state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a method of manufacturing the same, and more particularly to a QTP (Quad Tape carrier Packag).
The present invention relates to a semiconductor device having a structure similar to that of e) and a method of manufacturing the same. 2. Description of the Related Art In recent years, with the downsizing and high performance of electronic devices, the semiconductor devices mounted therein are also tending to have a large number of pins and are small and thin. Further, in recent years, semiconductor devices have been rapidly increased in speed, and in order to cope with this increase in speed, improvement in electrical characteristics such as noise countermeasures and improvement in thermal characteristics are also required.

[0002]

2. Description of the Related Art Conventionally, the QFP (QFP (Q
uad Flat Package), QTP (Quad Tape carrier Packag
Various types of packages such as e) and BGA (Ball Grid Array) have been developed.

The QFP has a structure in which leads extend from each of the four side surfaces of a rectangular resin package, and each lead is formed in a gull-wing shape so as to correspond to surface mounting. In addition, the QTP is a TAB having a lead formed by a copper foil or the like on a tape-shaped insulating film as a lead
(Tape Automated Bonding) tape is used so that the lead pitch is narrower than that of QFP. Further, the BGA has a structure in which a large number of balls functioning as external terminals are arranged on the back surface side of the printed wiring board, and a semiconductor element is mounted on the front surface side and sealed with resin.

Here, the above-mentioned QFP, QTP, BGA
The various characteristics of each are summarized in the table below.

[0005]

[Table 1]

From Table 1 above, the following can be said for each characteristic. (1) Higher density The BGA, which can arrange terminals in a grid pattern, is the most efficient and high-density package. Next to this, QT capable of narrowing pitch
P density can be increased. (2) Package cost The lowest cost is QFP, which is mainly composed of single-layer metal plate lead members, wires, resin, etc., except for semiconductor elements. In addition, a BG having a structure in which the lead member is replaced with a multi-layer substrate with respect to the QFP, and a ball attaching process is added.
A is the highest cost. Further, QTP has a higher cost than QFP in that the lead member is a TAB tape (multilayer film), but it is possible to suppress the cost increase more than BGA. (3) Mounting cost Since BGA and QFP can be collectively reflow mounted, the mounting cost is low. In addition, since BGA generally has a higher mounting yield, BGA has the lowest cost. On the other hand, in QTP, the outer lead is normally formed and individually mounted by a hot bar or the like, so that the mounting cost becomes very high. (4) Regarding thermal characteristics Regarding thermal characteristics, QFP, QTP, and BGA all show similar characteristics, but when mounted on a mounting board, the distance between the mounting board and the semiconductor element is short, so that the heat transfer path Short QTP is the best. (5) Electrical characteristics BGA has a power supply and ground (GN
Although D) is easy to separate and integrate, the signal line itself is not constant in length and arrangement, and it is difficult to control the characteristics. On the other hand, QTP has good electrical characteristics because the length from the semiconductor element to the mounting board is short and uniform. (6) Thinning QTP using TAB tape as a lead is overwhelmingly advantageous as compared with other configurations. (7) Mounting part reliability Regarding the mounting part reliability against temperature cycle, BG
A has few data and is difficult to evaluate under the present conditions. Therefore, it can be said that the risk is high. In addition, QTP has a greater life-prolonging effect due to stress relaxation than QFP.

As described above, although QTP is inferior to other package structures in mounting cost, it has good other characteristics.

[0008]

As described above, the QTP
Shows good characteristics except the mounting cost. Therefore, QT
If the mounting cost can be reduced in P, a package having extremely good characteristics can be realized. That is, a semiconductor device that satisfies all characteristics can be realized by configuring the QTP so that it can be packaged in a single flow.

Therefore, the problems to be solved in order to implement the QTP batch reflow mounting will be described below. (1) Acquisition of lead flatness In order to carry out reflow soldering of QTP at one time, it is necessary to preliminarily shape the outer lead into a shape that facilitates mounting such as QFP. However, the QTP lead is usually formed of copper foil, and its strength is very weak. Therefore, the Q of the conventional configuration
The TP has a problem that it is only possible to obtain lead flatness at the time of collective reflow mounting, and thus it is impossible to perform collective reflow mounting. (2) Lead protection As described above, the QTP having the conventional structure has very weak strength because the leads are made of copper foil. Therefore, it is necessary to protect the molded outer leads until the mounting is performed after the lead molding. However, the conventional QTP does not have a structure for protecting the outer leads, and thus has a problem that the outer leads may be deformed before mounting after lead molding. (3) Correspondence to narrow pitch mounting Even if the above problems are solved and the outer lead accuracy equal to that of QFP is obtained, the arrangement of the mounting portion equivalent to QFP can achieve only the same high density as QFP. At the present time, the narrow pitch limit of QFP by batch reflow mounting is about 0.3 mm, and the narrow pitch limit of QTP by individual mounting (that is, in the mounting process currently performed) is 0.15 mm. Therefore, if batch reflow mounting cannot be realized while maintaining a narrow pitch of 0.15 mm, QT
It makes no sense to carry out the reflow mounting of P collectively (the high density cannot be achieved).

The present invention has been made in view of the above points, and it is an object of the present invention to provide a semiconductor device and a method of manufacturing the same which can realize good package characteristics in all characteristics.

[0011]

Means for Solving the Problems To solve the above problems, the present invention is characterized by taking the following means. According to another aspect of the invention, a semiconductor device is provided which includes a semiconductor element, a lead member for mounting the semiconductor element, and a package for sealing a part of the lead member and the semiconductor element, and which is surface-mounted on a mounting board. In the above, the lead member is disposed inside the frame-shaped base member that supports the package on the mounting substrate, and the tip portion is connected to the frame-shaped base member. And a foil-shaped lead protected by a frame-shaped base member, and the foil-shaped lead is curved and protrudes from the frame-shaped base member toward the mounting board when not mounted on the mounting board. The frame-shaped base member and the foil-shaped leads are mounted on the mounting board by the flexible deformation of the foil-shaped leads when mounted on the mounting board. It is characterized in that it has configured to be dihedral one-state.

According to a second aspect of the invention, in the semiconductor device according to the first aspect, the lead member extends from one side surface of the package, and the package is formed by the frame-shaped base member. The present invention is characterized in that the mounting board is supported in an upright state.

According to a third aspect of the present invention, in the semiconductor device according to the first or second aspect, the mechanical strength is weaker at the lowermost end portion of the foil-shaped lead as compared with other portions. It is characterized in that a fragile portion configured as described above is formed.

According to a fourth aspect of the present invention, in the semiconductor device according to the third aspect, the foil-shaped leads are arranged in a zigzag manner at the positions where the weak portions are formed, and the foil is in a curved state. It is characterized in that the lowermost end portion of the linear lead is staggered.

According to a fifth aspect of the invention, in the semiconductor device according to any one of the first to fourth aspects, the frame-shaped base member is formed of a conductive material, and
The foil-shaped lead is connected to the frame-shaped base member via an insulating material, and the frame-shaped base member is electrically connected to the semiconductor element, whereby the frame-shaped base member is used as a lead. To do.

Further, according to the invention of claim 6, in the method of manufacturing a semiconductor device, a plurality of strip-shaped leads are arranged on the frame-shaped base member having the slits so as to be located in the slits. A lead member forming step of forming a flat plate-shaped lead member, and a semiconductor element mounting step of mounting a semiconductor element on the lead member and electrically connecting the inner lead portion of the foil lead and the semiconductor element. A package forming step of forming a package for encapsulating the inner lead portion of the lead member and the semiconductor element, and folding the frame-shaped base member so that the foil-shaped leads protrude from the frame-shaped base member toward the mounting substrate. And a lead member forming step of bending.

Each of the above means operates as follows. According to the first aspect of the present invention, the lead member is formed by the frame-shaped base member and the foil-shaped lead which is disposed inside the frame-shaped base member and whose tip is connected to the frame-shaped base member. With this configuration, the foil-shaped lead is protected by the frame-shaped base member. Therefore, the molded foil-shaped leads are protected by the frame-shaped base member and are prevented from being deformed until they are mounted after the foil-shaped leads are molded. It is possible to prevent the occurrence of defects.

Further, since the tip end of the foil-shaped lead is connected to the frame-shaped base member and the other end is supported by the package, the foil-shaped lead is convex downward when not mounted on the mounting board. The parabolic shape is obtained. The lower end of the foil-shaped lead is projected from the frame-shaped base member toward the mounting substrate, and the portion of the foil-shaped lead projected from the frame-shaped base member functions as an external connection terminal.

The portion of the foil-shaped lead that functions as an external connection terminal is flexibly deformed when mounted on the mounting board and electrically connected to the mounting board. Even if there is some variation in the amount of protrusion, the variation is absorbed by the flexible deformation of the foil lead. That is, in the mounted state (the mounted state before performing the reflow process), each foil-shaped lead is in a state of reliably contacting the mounting substrate. Therefore, it is possible to substantially maintain the flatness of the foil-shaped leads, and it is possible to carry out the collective reflow mounting.

Furthermore, since the foil-shaped lead is protected by the frame-shaped base member as described above, it is not necessary to give the foil-shaped lead itself mechanical strength for preventing deformation. Therefore, the foil-shaped leads can be formed thin and thin, and the lead pitch can be narrowed. This enables narrow pitch mounting.

According to the second aspect of the present invention, the lead member extends from one side surface of the package, and the package is supported by the frame-shaped base member in an upright state on the mounting substrate. As a result, the packaging density can be improved as compared with the configuration in which the packages are mounted side by side.

According to the third aspect of the invention, the fragile portion is formed at the lowermost portion of the foil-like lead so as to have a mechanical strength lower than that of the other portions. The foil-like lead has a curved shape with the fragile portion being the lower end. Therefore, by appropriately setting the formation position of the fragile portion, it is possible to realize the foil lead having an arbitrary curved shape.

Further, according to the invention of claim 4, the positions where the fragile portions are formed are arranged in a zigzag manner by the adjacent foil-shaped leads, and the lowermost end portion of the foil-shaped leads in a curved state is a zigzag shape. With such a configuration, the lead pitch can be narrowed while separating the bonding (for example, solder bonding) positions of the mounting substrate and the foil-shaped leads. That is, it is possible to reduce the pitch of the foil leads and improve the mountability.

According to the fifth aspect of the present invention, the frame-shaped base member is formed of a conductive material, and the foil-shaped leads are connected to the frame-shaped base member through an insulating material to form a frame-shaped base member. The frame-shaped base member can be used as a lead by electrically connecting the semiconductor elements. As a result, the number of leads can be increased, and the degree of freedom in electrical connection between the semiconductor device and the mounting substrate can be improved. In particular, since the frame-shaped base member has a smaller electric resistance than the foil-shaped leads, the electric characteristics can be improved by using it as a power or ground lead.

Further, according to the invention of claim 6, in the lead member forming step, the foil-shaped lead is arranged so as to be positioned in the slit formed in the frame-shaped base member to form the flat lead member. Then, the frame-shaped base member that constitutes this lead member is bent and formed in the lead member molding step, so that the frame-shaped base member and the foil-shaped leads are molded (curved) at the same time. You can Therefore, the molding process of molding the lead member can be performed easily and efficiently.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will now be described with reference to the drawings. 1 and 2 show a semiconductor device 1 which is a first embodiment of the present invention, and FIG.
2 is a plan view of the semiconductor device 1. FIG. 1 and 2 show a state before the semiconductor device 1 is mounted on the mounting substrate 2 (unmounted state), and FIG. 3 shows a state in which the semiconductor device 1 is mounted on the mounting substrate 2.

The semiconductor device 1 is roughly composed of a semiconductor element 3
(Appears in FIG. 6), the lead member 4, the resin package 5, and the like. The semiconductor element 3 is a highly densified element, and accordingly has a large number of electrode pads. The resin package 5 is formed by transfer molding of epoxy resin, for example.
By sealing a part of the lead member 4 and the semiconductor element 3, they have a function of protecting them.

The lead member 4 is a feature of the present invention, and is roughly composed of a frame-shaped base member 6, a foil-shaped lead 7, an insulating material 8 (shown in FIGS. 4 and 5) and the like. . The lead member 4 mounts the semiconductor element 2 at a portion embedded in the resin package 5, and in the present embodiment, extends outward from each of the four side surfaces of the resin package 5 to form outer lead portions. There is.

The frame-shaped base member 6 is made of, for example, a copper alloy such as 42 alloy, and its thickness is set relatively thick, for example, about 0.1 to 0.2 mm.
A stage portion 9 (shown in FIG. 6) on which the semiconductor element 3 is mounted is formed in the central portion of the frame-shaped base member 6, and four frame-shaped portions are provided at four outer peripheral positions of the stage portion 9. 10 are formed. The frame-shaped portion 10 is formed by punching a rectangular slit 11 in the plate-shaped frame-shaped base member 6.

Further, in this embodiment, the frame-shaped base member 6 is electrically connected to the semiconductor element 3 in the resin package 5 and is configured so as to also function as a lead. As a result, since the frame-shaped base member 6 can be used as a lead in addition to the foil-shaped lead 7, the number of leads can be increased, and the degree of freedom in electrical connection between the semiconductor device 1 and the mounting substrate 2 can be increased. Can be improved. In particular, since the frame-shaped base member 6 has a large cross-sectional area and a small electrical resistance with respect to the foil-shaped leads 7, the electrical characteristics can be improved by using it as a power or ground lead.

On the other hand, the foil-shaped lead 7 has a thickness of 0.01, for example.
A copper foil of 5 to 0.075 mm is formed in a strip pattern, and is composed of an inner lead portion 7a and an outer lead portion 7b (shown in FIG. 6). The inner lead portion 7 a is electrically connected to the semiconductor element 3 inside the resin package 5.

The inner lead portion 7a of the foil-shaped lead 7
Is held by being sealed in the resin package 5, and the tip portion of the outer lead portion 7b is attached to the frame-shaped portion 10 of the frame-shaped base member 6 by the insulating material 8 that also functions as an adhesive.
Are connected (adhered) by. That is, the foil-shaped leads 7 are arranged so as to be positioned inside the frame-shaped portion 10, and the foil-shaped leads 7 are arranged in the rectangular slit 1 formed in the frame-shaped portion 10.
It is arranged so that 1 may be crossed.

Therefore, the thickness is 0.015 to 0.075 m.
Even if the foil-shaped lead 7 is thin and has a low mechanical strength, the frame-shaped base member 6 protects the foil-shaped lead 7. After the molding process of the foil-shaped lead 7, the mounting is performed on the mounting substrate 2 as described below. The foil-shaped lead 7 formed into a predetermined shape is protected by the frame-shaped base member 6 and its deformation is prevented. This allows
It is possible to prevent a short circuit from occurring between the foil leads 7 and a connection failure during mounting.

Since the foil-shaped lead 7 is protected by the frame-shaped base member 6 as described above, it is not necessary to provide the foil-shaped lead 7 itself with mechanical strength for preventing deformation. Even if the foil thickness of 7 is as thin as 0.015 to 0.075 mm, it can function as a lead. This makes it possible to reduce the width dimension of the foil-shaped leads 7 and set the dimension between adjacent foil-shaped leads 7 to be small. Therefore, the pitch of the foil-shaped leads 7 can be narrowed, and specifically, the pitch can be narrowed to the same extent as QTP (0.
A narrow pitch of 15 mm) can be realized.

The tip of the foil-shaped lead 7 is connected to the frame-shaped base member 6 as described above. At this connection position, the foil-shaped lead 7 is connected to the frame-shaped base member 6 via the insulating material 8. Therefore, the frame-shaped base member 6 and the foil-shaped leads 7 are not electrically connected.

On the other hand, the frame-shaped base member 6 is bent and formed in a substantially U shape in a side view (see FIG. 1). The frame-shaped base member 6 bent and formed in a substantially U shape
The lower end portion of the supporting portion 1 extends horizontally with respect to the mounting board 2.
2 is formed, and when the semiconductor device 1 is mounted on the mounting substrate 2, the supporting portion 12 contacts the mounting substrate 2 to support the resin package 5 on the mounting substrate 2. .

Further, as described above, the foil-shaped lead 7 is configured such that one end is held by the resin package 5 and the tip is connected to the frame-shaped base member 6, so that the frame-shaped base member 6 is By bending into the shape shown in FIG. 1, a downwardly convex parabola is curved. Further, by bending the frame-shaped base member 6, the lower end portion of the foil-shaped lead 7 curved in a parabolic shape (hereinafter, this lower end portion is referred to as the bent portion 13) is a support portion 12 of the frame-shaped base member 6. It is configured to project further downward.

The surfaces of the frame-shaped base member 6 and the foil-shaped leads 7 are palladium-plated, gold-plated, or solder-plated in order to improve the solder joint property when soldering to a mounting substrate 2 described later. Is being done. Next, a method of mounting the semiconductor device 1 having the above structure on the mounting board 2 will be described.

In order to mount the semiconductor device 1 on the mounting substrate 2, cream solder is applied to the electrodes formed on the mounting substrate 2 and the portions to which the frame-shaped base member 6 and the foil leads 7 are connected in advance. Keep it. Then, the semiconductor device 1 is placed on the mounting substrate 2 on which the cream solder is applied at a predetermined position.

When this mounting process is performed, as described above, the semiconductor device 1 is configured such that the parabolic curved foil-shaped leads 7 project downward from the supporting portion 12 of the frame-shaped base member 6. According to the processing, the bent portion 13 located at the lower end first comes into contact with the mounting substrate 2. Subsequently, the foil-shaped leads 7 are flexibly deformed by the weight of the semiconductor device 1, and eventually the supporting portions 12 of the frame-shaped base member 6 come into contact with the mounting substrate 2.

By the support portion 12 coming into contact with the mounting substrate 2 in this way, the resin package 5 becomes a frame-shaped base member 6.
Thus, the structure is supported on the mounting substrate 2. Further, in this supporting state, the portion of the foil-shaped lead 7 that is in contact with the mounting substrate 2 and the supporting portion 12 of the frame-shaped base member 6 are flush with each other on the mounting substrate 2 and function as an external connection terminal. The portions of the member 6 that project downward from the support portion 12 when the support portion 12 and the foil-shaped lead 7 are not mounted are in a state of being connected to the mounting substrate 2 (temporary connection state). FIG.
Shows a state in which the semiconductor device 1 is placed on the mounting substrate 2.

By the way, the portion of the foil-shaped lead 7 projecting downward from the supporting portion 12 functioning as an external connection terminal is flexibly deformed when mounted on the mounting board 2 and is connected to the mounting board 2. Therefore, even if there is a slight variation in the amount of protrusion of the foil-shaped lead 7 from the support portion 12, the variation can be absorbed by the foil-shaped lead 7 being flexibly deformed. That is, in the mounting state (mounting state before performing the reflow process), each foil-shaped lead 7 is mounted on the mounting substrate 2
Can be reliably brought into contact with. As a result, the flatness of the foil-shaped leads 7 is substantially maintained, and it becomes possible to carry out batch reflow mounting.

As described above, in the semiconductor device 1 according to the present embodiment, the foil-shaped leads 7 are protected by the frame-shaped base member 6 to prevent deformation, and the foil-shaped leads 7 are also prevented.
When the semiconductor device 1 is mounted on the mounting substrate 2, batch reflow mounting can be performed by substantially maintaining the flatness of the foil-shaped leads 7 by making the flexible deformation possible.

Therefore, after the semiconductor device 1 is mounted on the mounting substrate 2, the mounting substrate 2 on which the semiconductor device 1 is mounted is loaded in the reflow furnace and a collective reflow process is performed. As a result, the binder contained in the cream solder is removed, and the supporting portions 12 of the frame-shaped base member 6 and the predetermined portions of the foil leads 7 are soldered to the mounting substrate 2. As described above, since the semiconductor device 1 can be mounted on the mounting substrate 2 by the collective reflow mounting, the mounting cost can be reduced and the mounting efficiency can be improved.

FIG. 7 shows the soldering state of the foil leads 7 after the batch reflow process. As shown in the figure, since the foil-shaped lead 7 has a downwardly convex parabolic shape and is flexibly deformed when the semiconductor device 1 is mounted on the mounting substrate 2, after the batch reflow processing. In, the solder fillet is formed in two places (indicated by reference numerals 14a and 14b). Therefore, the foil-shaped leads 7 and the mounting substrate 2 can be reliably soldered.

Next, a method of manufacturing the semiconductor device 1 having the above structure will be described. The manufacturing method of the semiconductor device 1 according to the present embodiment roughly includes a lead member forming step, a semiconductor element mounting step, a package forming step, a lead member forming step, and the like. To manufacture the semiconductor device 1, first, the lead member forming step is performed to form the lead member 4. In the lead member forming step, first, the rectangular slit 1 is formed by pressing a flat copper alloy substrate.
1 is formed to form the frame-shaped portion 10, and unnecessary portions are removed to form the frame-shaped base member 6 having a cross shape as a whole.

Subsequently, an insulating material 8 which also functions as an adhesive is applied to one surface of the frame-shaped base member 6, and a copper foil is bonded to the upper surface of the frame-shaped base member 6 on the insulating material 8. This copper foil is a thin copper foil having a thickness of about 0.015 to 0.075 mm, for example. This copper foil is subjected to an etching treatment to form a plurality of strip-shaped foil leads 7 having a predetermined pitch.
Is formed. The lead member 4 is formed by performing the above processing. In this state, as shown in FIGS. 4 and 5, the tip ends of the foil-shaped leads 7 are connected (fixed) to the frame-shaped portion 10 by the insulating material 8.

When the lead member forming step is completed,
Then, a semiconductor element mounting process is performed. In the semiconductor element mounting step, first, the semiconductor element 3 is mounted on the stage portion 9 formed in the center of the frame-shaped base member 6 forming the lead member 4 using an insulating die-bonding material. Then, the electrode pad formed on the upper part of the semiconductor element 3 and the inner lead portion 7 a of the foil-shaped lead 7 forming the lead member 4 are electrically connected using the wire 15. Further, as described above, in the present embodiment, the frame-shaped base member 6 is also used as the lead, so that the frame-shaped base member 6 is used.
The predetermined position and the semiconductor element 3 are also electrically connected using the wire 15.

In the semiconductor element mounting step described above, the wire 15 is used as a means for joining the semiconductor element 3 and the foil lead 7 to each other. However, a bump is formed on the semiconductor element 3 instead of the wire 13. Alternatively, the semiconductor element 3 and the foil-shaped lead 7 may be joined by flip-chip joining.

As described above, the semiconductor element 3 is connected to the lead member 4
When the semiconductor element mounting process to be mounted on is completed, the package forming process is subsequently performed. The package forming step is a step of forming the resin package 5, and is formed by loading the lead member 4 on which the semiconductor element 3 is mounted in the mold as described above and performing the transfer molding process.

Resin package 5 formed in this way
Is configured to seal and protect the semiconductor element 3, the wire 15, and the inner lead portion 7a of the foil lead 7. 4 to 6 show a state where the package forming process has been performed. When the package forming process is completed, the lead member forming process is subsequently performed.
In the lead member forming step, the frame-shaped base member 6 is formed by bending into a substantially U-shape as shown in FIGS. As a result, the support portion 12 is formed on the frame-shaped base member 6.

As a matter of fact, the press working is performed only on the frame-shaped base member 6, and the foil-shaped leads 7 are not directly molded. Therefore, the foil-shaped lead 7 is not damaged by this lead member forming step. Further, since the frame-shaped base member 6 is bent and formed in a substantially U-shape as described above, the frame-shaped portion 10 to which the tip ends of the foil leads 7 are connected comes close to the resin package 5. As a result, the foil-shaped lead 7 is bent,
Therefore, the downward convex parabolic curve shown in FIG. 1 naturally occurs due to its own weight.

At this time, by appropriately selecting the curvature for bending the frame-shaped base member 6, the foil-shaped lead 7 is supported by the support portion 12.
It is possible to arbitrarily set the amount of protrusion from the. Therefore, the amount of protrusion of the foil-shaped lead 7 from the supporting portion 12 is such that when the semiconductor device 1 is mounted on the mounting substrate 2 by appropriately setting the above-mentioned curvature, a deflection that does not cause a buffer between adjacent foil-shaped leads 7 is generated. The amount is set to occur.

The semiconductor device 1 is manufactured by carrying out the series of steps described above. At this time, as described above, in the lead member forming step, the foil-shaped lead 7 is formed so as to be positioned inside the rectangular slit 11 formed in the frame-shaped base member 6, and the flat plate-shaped lead member 4 is formed. The frame-shaped base member 6 and the foil-shaped leads 7 are molded at once by bending and forming only the frame-shaped base member 6 that constitutes the member 4 in the lead member molding step. be able to. Therefore, by adopting the above manufacturing method, the molding process of the lead member 4 can be performed easily and efficiently.

In the embodiment described with reference to FIGS. 1 to 6, the semiconductor device 1 having a structure similar to QTP in which the foil-shaped leads 7 extend from the four side surfaces of the resin package 5 is taken as an example. did. However, the foil-shaped leads 7 do not necessarily have to extend from the four side faces of the resin package 5, and may have a configuration of extending from the two opposite side faces. With this configuration, an SOJ (Small Out-line J-leaded package) type or SOP (Small Out-line package) type semiconductor device can be realized.

Further, the bent shape of the frame-shaped base member 6 is not limited to the substantially U-shaped shape, and may be any other shape as long as the above-described function of the frame-shaped base member 6 can be achieved. . Next, a second embodiment of the present invention will be described.

8 and 9 show a semiconductor device 20 according to the second embodiment of the present invention. FIG. 8 shows the semiconductor device 20 in an unmounted state, (A) is a front view, (B) is a side view,
(C) shows the bottom view, respectively. Further, FIG. 9 shows a state in which the semiconductor device 20 is mounted on the mounting substrate 2,
(A) is a front view and (B) is a side view. still,
In each drawing, the same reference numerals are given to the components corresponding to those of the semiconductor device 1 according to the first embodiment.

In the semiconductor device 20 according to this embodiment, the lead member 4 extends from only one side surface of the resin package 5, and the resin package 5 is mounted by the frame-shaped base member 6 forming the lead member 4. It is characterized in that it is configured to be supported on the substrate 2 in an upright state.

Also in this embodiment, the foil-shaped leads 7 constituting the lead member 4 are positioned and protected inside the rectangular slits 11 formed in the frame-shaped base member 6, and the tips thereof are frame-shaped. It is fixed to the part 10. FIG.
As shown in (B), the foil-shaped lead 7 has a downwardly convex parabolic curved shape, and a predetermined range of the lower end including the bent portion 13 projects downward from the support portion 12. ing.

On the other hand, as shown in FIG. 9, in the mounted state, the foil-shaped leads 7 projecting downward from the supporting portion 12 are flexibly deformed, and the supporting portion 12 and the foil-shaped leads 7 are mounted on the mounting substrate 2.
It is in the same state as above. Therefore, also in the semiconductor device 20 according to the present embodiment, the lead flatness can be substantially obtained, the foil-shaped leads 7 can be surely protected, and the hail pitch mounting can be realized. As a result, it is possible to use collective reflow mounting when mounting the semiconductor device 20 on the mounting substrate 2, and it is possible to reduce the mounting cost and improve the mounting efficiency.

Furthermore, the semiconductor device 20 according to the present embodiment is
The resin package 5 is mounted on the mounting substrate 2 by the frame-shaped base member 6.
It can be supported in an upright position. Therefore, the mounting space can be made smaller than that of the semiconductor device 1 shown in the first embodiment in which the resin package 5 is laterally provided on the mounting substrate 2 (disposed in a flat state), and the semiconductor device 20 is provided. The packaging density of can be improved.

Next, a third embodiment of the present invention will be described. 10 to 13 show a semiconductor device 30 according to the third embodiment of the present invention. Since the present embodiment is particularly characterized by the foil-shaped leads 31 and 32 of the semiconductor device 30, the foil-shaped leads 31 are shown enlarged in each drawing. In each drawing, the same components as those of the semiconductor device 1 according to the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in the respective drawings, the semiconductor device 30 according to the present embodiment has a zigzag shape by alternately changing the positions of the bent portions 33 and 34 in the adjacent foil leads 31 and 32. It is characterized by being configured as described above. In this way, the curved foil-shaped leads 31,
By forming the bent portions 33 and 34, which are the lower end portions of 32, at different positions between the adjacent foil-shaped leads 31 and 32 so as to form a zigzag shape, the mounting substrate 2 and the foil-shaped leads 31 and 3 are formed.
It is possible to narrow the lead pitch while separating the solder joint position with the lead wire 2.

FIG. 13 shows a state in which the semiconductor devices 30 having a zigzag shape in which the formation positions of the bent portions 33 and 34 are made different by the adjacent foil leads 31 and 32 are mounted on the mounting substrate 2 (soldered state). Shows. As shown in the drawing, the bent portions 33 and 34 of the adjacent foil leads 31 and 32 have a zigzag shape, so that the solder bonding positions are separated from each other. Therefore, according to the semiconductor device 30 of the present embodiment,
It is possible to reduce the pitch of the foil leads 31 and 32 and improve the mountability.

Next, a description will be given of a structure in which the bent portions 33 and 34 are formed in different zigzag positions in the adjacent foil leads 31 and 32 so as to form a zigzag shape. As described above, when the frame-shaped base member 6 is bent and formed into a predetermined shape, the foil-shaped leads 31 and 32 are bent by their own weight and curved in a parabolic shape convex downward. Therefore, when the foil-shaped leads 31 and 32 have a uniform structure, the center positions of the foil-shaped leads 31 and 32 are bent portions 33 and 34, and the bent portions 33 and 34 are located at the same position. It does not become a state.

Therefore, in this embodiment, when the frame-shaped base member 6 is bent, the foil-shaped leads 31 and 32 are flexibly deformed (curved) so as to be convex downward, as compared with other portions. The fragile portion 35 is formed so that the mechanical strength is weakened. The fragile portion 35 may be, for example, a small hole 35a as shown in FIG. 14, or may be a structure in which a narrow portion 35b is formed as shown in FIG.

Further, in the present embodiment, the formation positions of the fragile portions 35 are arranged in a zigzag pattern between the adjacent foil-shaped leads 31 and 32, and the foil-shaped leads are bent in a downward convex shape. It was configured so that the lowermost end was staggered. With the above configuration, the foil leads 31 and 32 have a curved shape with the fragile portion 35 as the lower end. Therefore, the foil-shaped leads 31 and 32 having an arbitrary curved shape can be realized by appropriately setting the formation position of the fragile portion 35. Therefore, in the present embodiment, the formation positions of the fragile portions 35 are arranged in a staggered manner by the adjacent foil-shaped leads 31 and 32, and the lowermost ends of the foil-shaped leads 31 and 32 in the curved state are in a staggered manner. Configured. As a result, the lead pitch can be narrowed while the joining (for example, solder joining) positions of the mounting substrate 2 and the foil leads 31 and 32 are separated, and the pitch of the foil leads 31 and 32 can be narrowed. It is possible to improve the mountability together.

[0068]

According to the present invention as described above, the following various effects can be realized. According to the invention described in claim 1, since the foil-shaped leads are protected by the frame-shaped base member, it is possible to prevent a short circuit from occurring between the foil-shaped leads or a connection failure during mounting. it can.

Further, since the foil-shaped leads are flexibly deformed when they are mounted on the mounting substrate and electrically connected to the mounting substrate, the foil-shaped leads can be made substantially flat, and a batch reflow process can be performed. It becomes possible to implement. Further, as described above, since the foil-shaped leads are protected by the frame-shaped base member, the foil-shaped leads can be formed thin and thin to have a narrow pitch, and thus narrow-pitch mounting can be made possible.
Moreover, according to the second aspect of the present invention, it is possible to improve the packaging density as compared with the configuration in which the packages are mounted side by side.

According to the third aspect of the invention, the foil-shaped lead having an arbitrary curved shape can be realized by appropriately setting the formation position of the bent portion. Also,
According to the invention described in claim 4, the lead pitch can be narrowed while separating the bonding position between the mounting substrate and the foil-shaped leads, and thus the pitch of the foil-shaped leads can be narrowed and the mountability can be improved. We can work together.

According to the fifth aspect of the invention, since the frame-shaped base member can be used as a lead, the degree of freedom in electrical connection between the semiconductor device and the mounting substrate can be improved. In particular, since the frame-shaped base member has a smaller electric resistance than the foil-shaped leads, the electric characteristics can be improved by using it as a power or ground lead.

Further, according to the sixth aspect of the present invention, in the lead member forming step, the foil-shaped lead is arranged so as to be positioned in the slit formed in the frame-shaped base member to form the flat plate-shaped lead member. By bending and forming the frame-shaped base member that constitutes this lead member in the lead member molding step, shaping of the frame-shaped base member and shaping of the foil-shaped leads (shaping into a curved shape) can be performed collectively. Therefore, the shaping process of the lead member molding can be performed easily and efficiently.

[Brief description of the drawings]

FIG. 1 is a side view of a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a plan view of the semiconductor device according to the first embodiment of the present invention.

FIG. 3 is a side view showing a state in which the semiconductor device according to the first embodiment of the present invention is mounted on a mounting board.

FIG. 4 is a side view showing a state before a lead member shaping step is performed.

FIG. 5 is an enlarged view showing a lead member.

FIG. 6 is a partially cutaway plan view showing a state before a lead member shaping step is performed.

FIG. 7 is an enlarged view showing a soldering portion of a foil lead.

FIG. 8 shows a semiconductor device according to a second embodiment of the present invention, in which (A) is a front view, (B) is a side view, and (C) is a bottom view.

FIG. 9 shows a state in which a semiconductor device according to a second embodiment of the present invention is mounted on a mounting board, (A) is a front view,
(B) is a side view.

FIG. 10 is a side view showing a configuration in which foil leads are arranged in a staggered pattern.

FIG. 11 is a plan view showing a configuration in which foil leads are arranged in a staggered pattern.

FIG. 12 is a perspective view showing a configuration in which foil leads are arranged in a staggered pattern.

FIG. 13 is an enlarged view showing a soldering portion when the foil leads are arranged in a zigzag manner.

FIG. 14 is a plan view showing a configuration in which bent portions (small holes) are arranged in a zigzag manner on a foil lead.

FIG. 15 is a plan view showing a configuration in which bent portions (narrow portions) are arranged in a zigzag manner on a foil-shaped lead.

[Explanation of symbols]

 1, 20, 30 Semiconductor Device 2 Mounting Substrate 3 Semiconductor Element 4 Lead Member 5 Resin Package 6 Frame Base Member 7, 31, 32 Foil Lead 7a Inner Lead Part 7b Outer Lead Part 8 Insulation Material 10 Frame Part 11 Rectangular Slit 12 Supporting part 13 Bending part 15 Wire

Claims (6)

[Claims] 1. A semiconductor device comprising a semiconductor element, a lead member for mounting the semiconductor element, and a package for sealing a part of the lead member and the semiconductor element, which is surface-mounted on a mounting substrate, A frame-shaped base member that supports the package on the mounting substrate, and the lead member that is disposed inside the frame-shaped base member and has its tip connected to the frame-shaped base member. And a foil-shaped lead that is protected by the strip-shaped base member, and when not mounted on the mounting substrate, the foil-shaped lead is curved and protrudes from the frame-shaped base member toward the mounting substrate. Along with the mounting on the mounting board, the foil-shaped leads are flexibly deformed so that the frame-shaped base member and the foil-shaped leads are flush with the mounting surface of the mounting board. A semiconductor device characterized by being configured so as to be in a state. 2. The semiconductor device according to claim 1, wherein the lead member extends from one side surface of the package, and the package is erected on the mounting substrate by the frame-shaped base member. A semiconductor device having a structure to be supported. 3. The semiconductor device according to claim 1, wherein a fragile portion configured to have a lower mechanical strength than other portions is formed at a lowermost portion of the foil lead. A semiconductor device characterized by the above. 4. The semiconductor device according to claim 3, wherein the formation positions of the fragile portions are arranged in a zigzag manner by the adjacent foil-shaped leads, and the lowermost end portion of the foil-shaped leads in a flexibly deformed state is A semiconductor device having a zigzag shape. 5. The semiconductor device according to claim 1, wherein the frame-shaped base member is formed of a conductive material, and the foil-shaped leads are formed on the frame-shaped base member via an insulating material. A semiconductor device, wherein the frame-shaped base member is used as a lead by connecting and electrically connecting the frame-shaped base member and the semiconductor element. 6. A lead member forming step for forming a flat lead member by arranging a plurality of strip-shaped leads in a strip shape so as to be positioned in the slit, on a frame-shaped base member having a slit formed therein. A semiconductor element mounting step of mounting a semiconductor element on the lead member and electrically connecting the inner lead portion of the foil-shaped lead to the semiconductor element; and sealing the inner lead portion of the lead member and the semiconductor element. And a lead member molding step of bending the frame-shaped base member so that the foil-shaped leads project toward the mounting substrate from the frame-shaped base member. Of manufacturing a semiconductor device.