JP2003174137A - Semiconductor device and manufacturing method thereof - Google Patents

Abstract

(57) [Problem] To provide a semiconductor device in which a semiconductor element and a lead portion are formed on the same surface to reduce the overall thickness and enhance the heat dissipation effect of the semiconductor element. SOLUTION: The semiconductor element 22 and the semiconductor element 22
In a semiconductor chip 21 including a lead frame having a plurality of lead portions 23 extending toward the semiconductor device 22 and a resin material 25 for sealing the semiconductor device 22 and the lead portions 23, the semiconductor device 22 and the lead portions 23 are the same. The device electrode portion 27 and the lead portion 2 of the semiconductor device 22 are disposed on a plane.
3 was electrically connected on the same surface via a bonding wire 24, and the back surfaces of the semiconductor element 22 and the lead portion 23 were exposed to the back surface of the resin material 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device formed by using a lead frame and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, a chip type semiconductor device having a plurality of electrode portions (hereinafter referred to as a semiconductor chip) has a semiconductor element mounted on a metal lead frame having a lead portion and an island portion. It is formed by sealing the top with a resin material. The island portion is for supporting the semiconductor element, and is provided in the central portion of the lead frame. The lead portion is connected to the element electrode portion of the supported semiconductor element via a bonding wire or the like, and one end thereof is an external electrode portion connected to an external substrate. FIG. 10 shows a structure of such a conventional semiconductor chip 1, and FIG. 11 shows a lead frame 2 for forming the semiconductor chip 1.
This lead frame 2 is made of 42 alloy (Ni 42% N
A plurality of chip forming regions A in which the island portions 4 and the lead portions 7 are punched and formed are provided using a thin metal strip such as an i-Fe alloy), aluminum, or copper. The island portion 4 is provided at a substantially central portion of one chip forming area A, and is connected to the frame body 6 via the arm portion 10. Further, the lead portion 7 forms an external electrode of the semiconductor chip 1, and is extended toward the end portion of the island portion 4 according to the number of element electrodes of the mounted semiconductor element 3.

In order to form the individual semiconductor chips 1 as shown in FIG. 10, first, the semiconductor element 3 is placed on the island portion 4 of the lead frame 2 and the element electrode portion 5 of the semiconductor element 3 is formed. The lead portion 7 is connected with a bonding wire 8. Then, after the resin material 9 is filled and sealed around the lead portion 7 and the arm portion 10 with the semiconductor element 3 as the center, the lead portion 7 and the arm portion 10 outside the resin material 9 are separated from the frame main body 6 and separated from each other. The semiconductor chip 1 is taken out.

There is also proposed a semiconductor chip having a structure in which a semiconductor element is directly mounted on the tip of a lead portion without having a dedicated island portion and electrically connected by a solder bump or the like. The semiconductor chip having such a structure has the advantages that the lead frame can be processed in a simple shape and can be manufactured at low cost.

[0005]

However, as shown in FIG.
The semiconductor chip 1 manufactured by using the lead frame 2 as shown in FIG. 11 has the semiconductor element 3 mounted on the island portion 4, and therefore the semiconductor chip 1 depends on the thickness of the island portion 4. There was a limit to the thinning. Further, since the island portion 4 has to be formed according to the shape of the semiconductor element 3 to be mounted, there is a problem that the man-hour and the cost required for processing the lead frame 2 cannot be reduced.

Further, in a semiconductor chip having a structure in which the semiconductor element is directly mounted on the tip of the lead portion without providing a dedicated island portion, there is no heat dissipation member in direct contact with the semiconductor element, so that the heat dissipation effect is sufficient. Not. For this reason, some of the lead portions are shallowly etched to thin the portion on which the semiconductor element is mounted. However, unless the processing accuracy of etching is strictly limited, the thickness of the portion supporting the semiconductor element is reduced. It becomes non-uniform and the stability deteriorates,
Electrical troubles such as poor contact are likely to occur.

Therefore, a first object of the present invention is to provide a semiconductor device in which a semiconductor element and a lead portion are formed on the same surface to reduce the overall thickness and to enhance the heat dissipation effect of the semiconductor element. It is to be.

A second object of the present invention is to provide a method for manufacturing a semiconductor device which is easy to manufacture by simplifying the structure of the lead frame and achieving a saving effect of the members forming the lead frame. Is.

[0009]

In order to solve the above-mentioned problems, a semiconductor device according to claim 1 of the present invention includes a semiconductor element and a lead frame having a plurality of lead portions extending toward the semiconductor element. In a semiconductor device including the semiconductor element and a resin material that seals the lead section, the semiconductor element and the lead section are arranged on the same plane, and the element electrode section and the lead section of the semiconductor element are on the same plane. In addition to being electrically connected, the back surfaces of the semiconductor element and the lead portion are exposed to the back surface side of the resin material.

According to the present invention, unlike the conventional semiconductor device using a lead frame, it is not necessary to provide a dedicated island portion for mounting a semiconductor element. Therefore, the semiconductor device can be made thinner and the lead frame can be made thinner. Simplification of processing. Further, since the semiconductor element and the lead portion are formed on the same surface and the back surfaces of the semiconductor element and the lead portion are exposed on the back surface of the resin material when resin-sealed, the heat generated by the semiconductor element is effectively released. Can be made. In order to form such a semiconductor element and the lead portion on the same plane in a state of being separated from each other, the lead frame and the semiconductor element are placed on a peelable adhesive sheet material, and the wire bonding and the resin material are used. After forming a semiconductor device through filling,
It is obtained by peeling the adhesive sheet material.

A method of manufacturing a semiconductor device according to the present invention comprises a step of forming a lead frame composed of a frame main body and a plurality of lead portions extending inward of the frame main body, and attaching the lead frame to an adhesive sheet material. Attaching step, attaching the semiconductor element in a plane space surrounded by the lead portion, wire bonding the lead portion and the semiconductor element, and filling a resin material above the lead frame and the semiconductor element And a step of forming a resin molded body having a predetermined shape, and a step of peeling the adhesive sheet material from the resin molded body.

According to the present invention, the peelable adhesive sheet material is used as a base, and after the lead frame and the semiconductor element are attached to the base, the wire bonding step, the resin material filling step and the molding step are carried out. It is not necessary to form an island portion which is a supporting member for a semiconductor element as in the conventional case. Therefore, the lead frame can be easily processed, and the man-hour and cost can be reduced.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a semiconductor device and a method of manufacturing the same according to the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a perspective view of a semiconductor device of the present invention, and FIG. 2 is a sectional view of the semiconductor device.

As shown in FIGS. 1 and 2, the semiconductor device according to this embodiment (hereinafter referred to as the semiconductor chip 21).
Is composed of a semiconductor element 22, four lead portions 23 arranged around the semiconductor element 22, and a resin material 25 that seals the lead portion 23 and the semiconductor element 22.
The semiconductor element 22 is a square silicon crystal thin plate, and has element electrode portions 27 at four corners. The lead portion 23 is on the same surface as the semiconductor element 22 and is formed in a plane around each element electrode portion 27. And
The lead portion 23 and the element electrode portion 27 of the semiconductor element 22 are electrically connected by a bonding wire 24, and the upper portion is sealed with a resin material 25 to form a package of the semiconductor chip 21. Further, the back surface 23a of the lead portion 23 is exposed to form an electrode portion for connecting to an external substrate 26 such as a mother board as shown in FIG. 2, and the exposed back surface 22a of the semiconductor element 22 is the outside. It is a heat dissipation surface that contacts the substrate 26.

FIG. 3 shows a lead frame 31 which is a base for forming the semiconductor chip 21. The lead frame 31 is formed in a long shape with a material such as 42 alloy (Ni 42% Ni—Fe alloy), aluminum, copper, or the like as in the conventional case, and the chip forming region B for forming the semiconductor chip 21 is a matrix. A large number of arrays are formed. In each of the chip forming regions B, the lead portion 23 is formed from the frame body 32 via the arm portion 33. The central portion of the four lead portions 23 is a space for mounting the semiconductor element 22.

Next, a method of manufacturing the semiconductor chip 21 using the lead frame 31 will be described with reference to FIGS. First, the lead frame 31 as shown in FIG.
To form. The lead frame 31 is formed by punching a thin metal plate of 42 alloy or the like by etching, pressing, or the like, leaving the frame body 32 and the arm portions 33 and the lead portions 23 extending from the frame body 32. Next, as shown in FIG. 4, the formed lead frame 31 is attached onto a peelable adhesive sheet material 34. The adhesive sheet material 34 is formed of a polyester film having a thickness of about 125 μm, and has an acrylic adhesive applied on the surface. Then, as shown in FIG. 5, the semiconductor element 22 is attached to a substantially central portion of each chip forming region B on the adhesive sheet material 34. The bonding surface of the semiconductor element 22 bonded to the adhesive sheet material 34 is a surface on which the element electrode portion 27 is not formed. After mounting the semiconductor element 22 on the adhesive sheet material 34, as shown in FIG. 6, each element electrode portion 27 of the semiconductor element 22 and each corresponding lead portion 23 are connected by a bonding wire 24. Next, as shown in FIG. 7, a mold is arranged above the lead frame 31 and the epoxy resin material 25 is filled to a depth where the semiconductor element 22, the lead portion 23 and the bonding wire 24 are completely hidden. After the filled resin material 25 is cured and the mold is removed, as shown in FIG. 8, the adhesive sheet material 34 is removed from the back surface of the lead frame 31 by UV irradiation to reduce the adhesive force, or is peeled by hand. , Soak it in a solution to dissolve it, and remove it. Finally, as shown in FIG. 9, a dicing device is used to move the lead frame 31 in the X direction (X1, X2, ...
Xn) and the chip forming region B is divided along the cut lines assumed in the Y direction (Y1, Y2, ... Y4).

According to the semiconductor chip 21 having the above structure, when the lead frame 31 is formed, only the lead portions 23 corresponding to the number of the element electrode portions 27 of the semiconductor element 22 mounted on the frame body 32 are formed. Is easy and does not require man-hours. In addition, since the semiconductor elements 22 can be freely arranged within the plane space surrounded by the lead portions 23, the semiconductor elements 22 having different sizes, shapes, etc. are collectively incorporated in one lead frame 31. You can

In the semiconductor chip 21 of the above embodiment, the example in which the element electrode portion 27 of the semiconductor element 22 has four poles is shown, but the invention is not limited to such a semiconductor chip structure, and the lead of the lead frame 31 is not limited. By changing the configuration of the part 23, it can be applied to a semiconductor device having a small number of poles such as 2 poles or a multipole such as 4 poles or more. Further, in the above-described embodiment, a plurality of semiconductor chips 21 are simultaneously formed from one lead frame 31, but the manufacturing method of the present invention can be applied to the case where a single semiconductor chip is formed in a unit. Is.

[0019]

As described above, according to the semiconductor device of the present invention, it is necessary to provide a dedicated island portion for mounting a semiconductor element like a conventional semiconductor device using a lead frame. Since the semiconductor device is thin, it is possible to reduce the thickness of the semiconductor device and simplify the processing of the lead frame. Further, since the semiconductor element and the lead portion are formed on the same surface and the back surfaces of the semiconductor element and the lead portion are exposed on the back surface of the resin material when resin-sealed, the heat generated by the semiconductor element is effectively released. Can be made.

Further, according to the method of manufacturing a semiconductor device of the present invention, a peelable adhesive sheet material is used as a base, a lead frame or a semiconductor element is adhered on the base, and then a wire bonding step and a resin material filling process are performed. Also, since it is manufactured through the molding process, it is not necessary to form an island portion which is a supporting member for a semiconductor element as in the conventional case. Therefore, the structure of the lead frame is simplified and the material cost and the processing cost are reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of a semiconductor device according to the present invention.

FIG. 2 is a cross-sectional view when the semiconductor device of FIG. 1 is mounted on an external substrate.

FIG. 3 is a perspective view of a lead frame of the semiconductor device.

FIG. 4 is an explanatory diagram showing a state in which a lead frame is attached to an adhesive sheet material.

FIG. 5 is an explanatory diagram showing a state in which a semiconductor element is attached to an adhesive sheet material.

FIG. 6 is an explanatory diagram showing a state in which a lead portion and a semiconductor element are connected by a bonding wire.

FIG. 7 is an explanatory diagram showing a state where a lead frame is filled with a resin material.

FIG. 8 is an explanatory diagram showing a state in which an adhesive sheet material is peeled off from the lead frame.

FIG. 9 is an explanatory diagram showing a state in which a plurality of semiconductor devices formed on the lead frame are cut into individual semiconductor devices.

FIG. 10 is a perspective view of a conventional semiconductor device.

FIG. 11 is a perspective view of a lead frame of the conventional semiconductor device.

[Explanation of symbols]

21 Semiconductor chip (semiconductor device) 22 Semiconductor element 23 Lead 24 Bonding wire 25 resin material 27 Element electrode part 31 lead frame 34 Adhesive sheet material

Claims (3)

[Claims] 1. A semiconductor device comprising a semiconductor element, a lead frame having a plurality of lead portions extending toward the semiconductor element, and a resin material for sealing the semiconductor element and the lead portion, wherein the semiconductor element The lead part is arranged on the same plane,
A semiconductor device in which the element electrode portion and the lead portion of the semiconductor element are electrically connected on the same surface and the back surfaces of the semiconductor element and the lead portion are exposed to the back surface side of the resin material. . 2. The semiconductor element and the back surface of the lead portion are
The semiconductor device according to claim 1, wherein the semiconductor device is in contact with a peelable adhesive sheet material. 3. A step of forming a lead frame comprising a frame main body and a plurality of lead portions extending inward of the frame main body, a step of attaching the lead frame to an adhesive sheet material, and a semiconductor element for the lead. A step of attaching in a plane space surrounded by a part, a step of wire-bonding the lead part and the semiconductor element, and a resin molding having a predetermined shape by filling a resin material above the lead frame and the semiconductor element. A method of manufacturing a semiconductor device, comprising: a forming step; and a step of peeling an adhesive sheet material from the resin molded body.