JPH06209070A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To manufacture a highly reliable semiconductor device by securing the mechanical jointing strength of a lead frame, to which inner and outer leads which are separately manufactured in order to reduce the arranging pitch of the leads are jointed, at the time of jointing the leads and, at the same time, to prevent the inner leads at the time of handling the leads. CONSTITUTION:After fixing inner leads 6 with a polyimide tape 3 and cutting off the tie bar sections of the inner leads 6 which are molded with a resin 10, the junctions of the inner leads 6 with outer leads 7 are molded with the resin 10 and the tie bar sections not molded with the resin 10 are cut off.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device using a lead frame for narrowing the pitch.

[0002]

2. Description of the Related Art Conventionally, a method of manufacturing a lead frame of a semiconductor device includes a die pad portion on which a semiconductor element is mounted,
Inner leads that are connected to the semiconductor element with bonding wires and outer leads that are mounted on the wiring board are collectively formed by copper or 42 by a method such as stamping or etching.
Processing metal plates such as alloys. In recent years, with the increasing number of lead frames, inner leads with a narrow lead pitch are manufactured by TAB, etc., and outer leads with a relatively wide lead pitch are manufactured by different methods such as stamping and etching. By joining, a narrow pitch has been achieved.

A method of manufacturing a semiconductor device using a lead frame formed by joining inner leads and outer leads manufactured by another conventional method will be described below.

FIG. 12 is a sectional view of a semiconductor device which has been subjected to a lead forming step using a lead frame formed by joining inner leads and outer leads manufactured by a conventional semiconductor device manufacturing method, and FIG. 13 is a sectional view of a conventional semiconductor device. 12 is a perspective view of an inner lead frame and an outer lead frame of the semiconductor device shown in FIG. 12 manufactured by a manufacturing method. FIG. 14 is an inner lead and an outer lead of the semiconductor device shown in FIG. 12 manufactured by a conventional semiconductor device manufacturing method. FIG. 15 is a cross-sectional view at the time of joining with a semiconductor device, FIG. 15 is a cross-sectional view in which a semiconductor element is mounted on a lead frame of the semiconductor device shown in FIG. A semiconductor device lead frame manufactured by the method for manufacturing a semiconductor device shown in FIG. It is a cross-sectional view after the tie bar portion cut. Hereinafter, a conventional method of manufacturing a semiconductor device will be described. First, in order to accurately align the leads of the inner lead frame 1 shown in FIG. 13 produced by etching and the additive method and the outer lead frame 2 produced by stamping, the etching method, the tie bar portion 4 and the tie bar portion 5 are illustrated. After bonding by thermocompression bonding or the like as shown in FIG. 14, the semiconductor element 8 is mounted on the die pad 21 as shown in FIG. Thereafter, the semiconductor element 8 and the inner leads 6 are molded with the resin 10, and the tie bar portions 4 and 5 of the joint are cut to separate the inner leads 6 and the outer leads 7 as shown in FIG. Finally, in order to mount this semiconductor device on a wiring board, the outer lead 7 is connected to J or L as shown in FIG.
Forming into shapes such as letters.

[0005]

However, in the conventional method of manufacturing a semiconductor device, the inner lead frame 1 is used.
Since the lead pitch is narrow and the inner lead 6 is thin, the inner lead 6 is easily deformed in the line conveyance, the joining process, and the handling process in the cutting process of the tie bar portion 4 and the tie bar portion 5. In addition, in the method of joining the inner lead frame 1 and the outer lead frame 2, the lead joining portion is exposed to the outside of the resin 10, so that the appearance is poor, and the tie bar portion 4 and the tie bar portion 5 are cut or the outer lead 7 is formed. In addition, peeling and breakage of the lead joint part occur, and there is a problem that sufficient mechanical strength cannot be maintained.

The present invention solves the above-mentioned conventional problems and does not cause lead deformation during handling in the line conveying, joining process, and cutting process of the tie bar portion 4 and the tie bar portion 5, and the inner lead frame 1 and the outer lead are prevented. It is an object of the present invention to provide a method for manufacturing a semiconductor device in which a joint portion with the frame 2 has a sufficient mechanical joint strength against forming processing or the like.

[0007]

In order to achieve this object, the present invention separately manufactures the inner lead and the outer lead, joins the inner lead and the outer lead, and mounts the semiconductor element on a lead frame. Then, the joint between the inner lead and the outer lead is molded with resin.

[0008]

According to the present invention, since the joint portion between the inner lead frame and the outer lead frame is molded by the resin by the above-described manufacturing method, the appearance of the leads is not impaired, and the tie bar after resin molding is joined to the bending process such as cutting or lead forming. It is possible to maintain sufficient mechanical bonding strength of the parts.

[0009]

【Example】

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a semiconductor device manufactured by a method for manufacturing a semiconductor device according to a first embodiment of the present invention after lead forming. 2 is a perspective view of an inner lead frame and an outer lead frame after taping of the semiconductor device shown in FIG. 1 manufactured by the method for manufacturing a semiconductor device according to the first embodiment of the present invention, and FIG. 4 is a cross-sectional view of the semiconductor device shown in FIG. 1 manufactured by the method for manufacturing a semiconductor device according to the embodiment of FIG.
5 is a sectional view of the inner lead frame of the semiconductor device shown in FIG. 1 manufactured by the method for manufacturing a semiconductor device according to the first embodiment of the present invention after cutting the tie bar portion. FIG. 5 shows the first embodiment of the present invention. 1 is a cross-sectional view of a semiconductor device mounted on a lead frame of the semiconductor device shown in FIG. 1 manufactured by the semiconductor device manufacturing method, and FIG. 6 is a semiconductor device manufacturing method according to the first embodiment of the present invention.
FIG. 7 is a cross-sectional view of the lead frame of the semiconductor device shown in FIG. 1 molded with resin. FIG. 7 is a tie bar portion cut of the outer lead frame of the semiconductor device shown in FIG. It is a sectional view after. As shown in each drawing, 1 is an inner lead frame, 4 is a tie bar portion formed on the inner lead frame 1, and 6 is an inner lead.
Reference numeral 12 is an outer lead frame, 15 is a tie bar portion formed on the outer lead frame 12, and 7 is an outer lead. Also, 3 is a polyimide tape, 21
Is a die pad for mounting the semiconductor element 8, and 9 is a bonding wire for connecting the semiconductor element 8 and the inner lead 6. A resin 10 molds the semiconductor element 8 and the inner lead 6.

A method of manufacturing the semiconductor device of the present invention having the above structure will be described below.

First, as shown in FIG. 2, the inner leads 6 of the inner lead frame 1 produced by etching, an additive method or the like are fixed with a polyimide tape 3, and the tie bar portion 4 is produced by stamping, etching or the like. It is placed on the inner tip of the outer lead 7 which is a half of the plate thickness, and as shown in FIG. 3, the tie bar portion 4 and the outer lead 7 are joined by thermocompression bonding with a solder or gold plating layer or the like. To do. After this, the tie bar portions 4 connecting the inner leads 6 to each other are cut to obtain the state of FIG. 4, the semiconductor element 8 is mounted on the die pad 21 as shown in FIG. Connect with. Next, as shown in FIG. 6, the inner lead 6 and the semiconductor element 8 are molded so that the joint between the inner lead 6 and the outer lead 7 is not exposed to the outside, and the inside of the tie bar portion 15 is molded with the resin 10 to form a tie bar. The portion 15 is cut in the cutting step to be in the state of FIG. 7, and further subjected to lead forming to be in the state of FIG.

As described above, according to the first embodiment of the present invention, by fixing the inner leads 6 of the manufactured inner lead frame 1 with the polyimide tape 3, it is possible to carry out the line conveyance, the joining process, and the cutting process of the tie bar portion 4. The inner lead 6 is prevented from being deformed in handling, the inner lead frame 1 and the outer lead frame 12 are joined, the tie bar portion 4 is cut, the semiconductor element 8 is mounted, and then the inner lead 6 and the outer lead 7 are By molding with the resin 10 so that the joint portion of No. 1 does not come out to the outside, it is possible to maintain the mechanical strength of the joint portion of the inner lead 6 and the outer lead 7 against subsequent lead forming and the like.

(Second Embodiment) A second embodiment of the present invention will be described below with reference to the drawings. FIG. 8 is a sectional view of a semiconductor device manufactured by the method for manufacturing a semiconductor device according to the second embodiment of the present invention after lead forming. FIG. 9 is a perspective view of an inner lead frame and an outer lead frame after taping of the semiconductor device shown in FIG. 8 manufactured by the method for manufacturing a semiconductor device according to the second embodiment of the present invention, and FIG. 8 is a cross-sectional view of the semiconductor device shown in FIG. 8 manufactured by the method for manufacturing a semiconductor device according to the embodiment of FIG. 8 at the time of joining the inner lead and the outer lead, and FIG. 11 is a method for manufacturing a semiconductor device according to the second embodiment of the present invention. FIG. 9 is a cross-sectional view of the lead frame of the semiconductor device shown in FIG. As shown in each drawing, 1 is an inner lead frame, 4 is a tie bar portion formed on the inner lead frame 1, and 6 is an inner lead. Reference numeral 22 is an outer lead frame, 15 is a tie bar portion formed on the outer lead frame 22, and 7 is an outer lead. Further, 3 is a polyimide tape, 10 is a resin for molding the semiconductor element 8 and the inner lead 6, and the above is shown in FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG.
The configuration is the same as that of the first embodiment of the present invention shown in FIG. 3, except that the inner tie bar portion 11 is provided inside the tie bar portion 15 of the outer lead frame 22.

A method of manufacturing the semiconductor device of the present invention configured as described above will be described below.

First, as shown in FIG. 9, the inner leads 6 of the inner lead frame 1 produced by etching, an additive method or the like are fixed with a polyimide tape 3 and the tie bar portion 4 is made by stamping, etching or the like. It is placed on the inner tie bar portion 11 which is a half of the plate thickness, and as shown in FIG. 10, the tie bar portion 4 and the inner tie bar portion 11 are joined by thermocompression bonding with a solder or gold plating layer or the like. To do. After this, as in the case of FIGS. 4, 5 and 6 described in the first embodiment of the present invention, the tie bar portion 4 of the joint portion 4 is formed.
The inner tie bar portion 11 is cut, the semiconductor element 8 is mounted on the die pad 21, and the bonding wire 9 connects the inner lead 6. Next, the inner lead 6 and the semiconductor element 8 are connected to each other so that the joint portion between the inner lead 6 and the outer lead 7 does not come out to the outside and the tie bar portion 1
The inside of 5 is molded with resin 10 as shown in FIG.
It becomes the state of 1. Finally, as in the case of FIG. 7 described in the first embodiment of the present invention, the tie bar portion 15 is cut in the cutting step, and lead forming is performed to obtain the state of FIG.

As described above, according to the second embodiment of the present invention, by fixing the inner leads 6 of the manufactured inner lead frame 1 with the polyimide tape 3, the line transfer, the joining process, the tie bar portion 4, the inner tie bar portion are performed. 11
Of the inner lead frame 1 and the outer lead frame 22 are joined to each other at the tie bar portion 4 and the inner tie bar portion 11 in the handling in the cutting step, and the tie bar portion 4 and the inner tie bar portion of the joint portion are joined together. After the portion 11 is cut and the semiconductor element 8 is mounted, the joint portion between the inner lead 6 and the outer lead 7 is molded by the resin 10 so that the joint portion between the inner lead 6 and the outer lead 7 does not come out to the outside. The positioning accuracy can be significantly eased, and the mechanical strength of the joint between the inner lead 6 and the outer lead 7 against lead forming or the like after joining can be maintained.

[0017]

According to the present invention, the inner lead and the outer lead are manufactured separately, and after the inner lead and the outer lead are joined and the semiconductor element is mounted on the lead frame, the inner lead and the outer lead are joined together. Since the inner lead frame and outer lead frame joints are molded with resin by molding with resin, the machine does not damage the appearance of the leads and is a machine with sufficient joints for cutting tie bars after resin molding and bending such as lead forming. Since it is possible to maintain the desired bonding strength, it is possible to easily manufacture a semiconductor device having a lead frame with a narrowed pitch.

[Brief description of drawings]

FIG. 1 is a perspective view of a semiconductor device manufactured by a method for manufacturing a semiconductor device according to a first embodiment of the present invention after lead forming.

FIG. 2 is a perspective view of an inner lead frame and an outer lead frame after taping of the semiconductor device shown in FIG. 1 manufactured by the method of manufacturing a semiconductor device according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of the semiconductor device shown in FIG. 1 manufactured by the method for manufacturing a semiconductor device according to the first embodiment of the present invention when the inner lead and the outer lead are joined together.

FIG. 4 is a sectional view of the inner lead frame of the semiconductor device shown in FIG. 1 manufactured by the method of manufacturing a semiconductor device according to the first embodiment of the present invention after cutting the tie bar portion.

5 is a cross-sectional view of a semiconductor device mounted on a lead frame of the semiconductor device shown in FIG. 1 manufactured by the method for manufacturing a semiconductor device according to the first embodiment of the present invention.

FIG. 6 is a sectional view of a semiconductor device shown in FIG. 1 manufactured by a method for manufacturing a semiconductor device according to a first embodiment of the present invention, the lead frame being molded with a resin.

FIG. 7 is a sectional view of the outer lead frame of the semiconductor device shown in FIG. 1 manufactured by the method for manufacturing a semiconductor device according to the first embodiment of the present invention after cutting the tie bar portion.

FIG. 8 is a sectional view of a semiconductor device manufactured by a method of manufacturing a semiconductor device according to a second embodiment of the present invention after lead forming.

9 is a perspective view of an inner lead frame and an outer lead frame after taping of the semiconductor device shown in FIG. 8 manufactured by the method for manufacturing a semiconductor device according to the second embodiment of the present invention.

FIG. 10 is a cross-sectional view of the semiconductor device shown in FIG. 8 manufactured by the method for manufacturing a semiconductor device according to the second embodiment of the present invention when the inner lead and the outer lead are joined.

FIG. 11 is a cross-sectional view of a lead frame of the semiconductor device shown in FIG. 8 manufactured by the method for manufacturing a semiconductor device according to the second embodiment of the present invention, which is molded with resin.

FIG. 12 is a cross-sectional view of a semiconductor device that has been subjected to a lead forming process using a lead frame formed by joining inner leads and outer leads manufactured by a conventional semiconductor device manufacturing method.

13 is a perspective view of an inner lead frame and an outer lead frame of the semiconductor device shown in FIG. 12 manufactured by a conventional method of manufacturing a semiconductor device.

14 is a cross-sectional view of the semiconductor device shown in FIG. 12 manufactured by a conventional method for manufacturing a semiconductor device when the inner lead and the outer lead are joined together.

FIG. 15 is a cross-sectional view in which a semiconductor element is mounted on a lead frame of the semiconductor device shown in FIG. 12 manufactured by a conventional semiconductor device manufacturing method and is molded with resin.

16 is a sectional view of the lead frame of the semiconductor device shown in FIG. 12 manufactured by a conventional method for manufacturing a semiconductor device after cutting the tie bars.

[Explanation of symbols]

 1 Inner lead frame 3 Polyimide tape 4,15 Tie bar part 6 Inner lead 7 Outer lead 8 Semiconductor element 9 Bonding wire 10 Resin 11 Inner tie bar part 12,22 Outer lead frame 21 Die pad

Claims (2)

[Claims] 1. An inner lead of a lead frame on which a semiconductor element is mounted and an outer lead of the lead frame are manufactured separately, and the inner lead and the outer lead are joined and the semiconductor element is mounted on the lead frame. After that, a method of manufacturing a semiconductor device, characterized in that a joint portion between the inner lead and the outer lead is molded with resin. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the inner leads are fixed to each other with an insulating member.