JPH05109975A - Resin-sealed type semiconductor device - Google Patents

Abstract

PURPOSE:To simplify a process by joining a junction plate with a circuit forming surface of a first semiconductor element via an insulating member to be wire- bonded and by joining a non-circuit-forming surface of a second semiconductor element to the opposite side of the junction plate via an insulating member to be wire-bonded. CONSTITUTION:While a semiconductor element 1a with a circuit forming surface facing upward is mounted, a lead frame comprising an assembly of a junction plate 2 having smaller size than the semiconductor element 1a and having insulating members 5 on both sides and a lead 3 is mounted and joined so that an electrode pad lap is exposed. Then, a wire 4 is used to electrically connect the semiconductor element 1a to the lead 3. Then, a semiconductor element 1b is mounted and joined from an upper part of the junction plate 2 with a circuit forming surface facing upward, and the wire 4 is used to electrically connect the semiconductor element 1b to the lead 3. The assembly is sealed by resin 15 and molded with an unnecessary part of the lead 3 cut off. Thus, a manufacture process can be simplified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-encapsulated semiconductor device, and more particularly to a resin-encapsulated semiconductor device represented by a large capacity memory package having a plurality of semiconductor elements incorporated therein.

[0002]

2. Description of the Related Art In a resin-sealed semiconductor device such as a memory package, the storage capacity has been increasing year by year due to customer requirements, and the semiconductor element rule is becoming finer accordingly. For example, 64M DRAM (64Mbit Dynamic Random A
In ccess memory, the rule is 0.3 μm, which is said to be nearing the limit of miniaturization. Therefore, in the future, it will be effective to incorporate a plurality of semiconductor elements in the device in order to obtain a higher density package. As means for this purpose, many proposals including the following have been proposed and are well known.

(1) Japanese Patent Application Laid-Open No. 1-295454: Two semiconductor elements having different sizes are mounted on a lead frame with the larger one facing down, and the wires are used to electrically connect the leads to the semiconductor element. I do.

(2) Japanese Unexamined Patent Publication No. 2-2658: Non-circuit forming surfaces of a semiconductor element are joined to both surfaces of a lead frame, and electrical connection is made from both surfaces using wires.

(3) Nikkei Microdevice 1991 4
Monthly p. 80: The non-circuit forming surfaces of the semiconductor elements are overlapped with each other and electrically connected using TAB (Tape Automated Bonding).

[0006]

[Problems to be Solved by the Invention] (1) to (3)
Have the following problems, that is, the problems to be solved by the present invention.

(1) In the case of a memory package in which package outer dimensions are severely restricted, miniaturization of the outer dimensions of a semiconductor element is a very important issue, and therefore it is inevitable to change the size of two semiconductor elements. A wasteful area will be created in either side. For this reason, it is desirable that a plurality of the same semiconductor elements can be built in the memory package.

(2) By bonding the non-circuit forming surface of the semiconductor element to both surfaces of the lead frame, it is necessary to perform wire bonding from both surfaces, which requires a step of turning over the lead frame, and turning over. There is a possibility that inconvenience may occur, such as the wire on the lower surface being crushed. Therefore, it is desirable that wire bonding be performed in the same direction on any semiconductor element.

(3) The use of TAB for electrical connection between the semiconductor element and the lead is extremely disadvantageous in comparison with wire bonding in terms of manufacturing cost, and should be avoided as much as possible.

[0010]

The above object can be achieved by the following means.

(A) The bonding plate formed in the lead frame is bonded to the circuit forming surface of the first semiconductor element via an insulating member, and predetermined wire bonding is performed, and the bonding plate is formed on the opposite surface of the bonding plate. The non-circuit forming surface of the second semiconductor element is joined via an insulating member, predetermined wire bonding is performed again, and they are sealed and molded with resin to obtain a resin-sealed semiconductor device.

(B) The inner end portion of the lead assembly is joined to the circuit forming surface of the first semiconductor element via an insulating member, predetermined wire bonding is performed, and the insulating member is provided on the opposite surface of the lead. The non-circuit forming surface of the second semiconductor element is joined via, the lead assembly is joined to the circuit forming surface of the same semiconductor element via the insulating member, and the predetermined wire bonding is performed again, and the two The leads are electrically connected to each other, and they are sealed and molded with resin to obtain a resin-sealed semiconductor device. Alternatively, the two semiconductor elements each have an inner end portion of the lead assembly bonded to the circuit formation surface via an insulating member, and each wire bonding is performed in a predetermined manner. These are electrically connected to each other, and they are sealed and molded with resin to obtain a resin-sealed semiconductor device.

By the manufacturing method similar to (c) and (b), a resin-sealed semiconductor device having three or more semiconductor elements built therein is obtained.

[0014]

The present invention operates as follows corresponding to the above (a) to (c).

(A) The bonding plate is formed so as not to cover the electrode pads provided on the peripheral portion of the semiconductor element, so that wire bonding can be performed even when the bonding plate is bonded to the circuit forming surface of the first semiconductor element. Since the combined thickness of the bonding plate and the insulating members on both sides thereof is larger than the loop height of the wire, even if the second semiconductor element is mounted on the upper portion of the wire, it does not interfere with the wire. Therefore, according to the present invention, a large-capacity resin-sealed semiconductor device in which two identical semiconductor elements are embedded in the same direction can be obtained.

(B) An assembly of leads having a predetermined shape and an electrode pad group provided along the longitudinal direction of the central portion of the first semiconductor element are electrically connected to each other on the circuit forming surface of the same semiconductor element. Although it is connected, the combined thickness of the lead and the insulating members on both sides is greater than the loop height of the wire, so even if a second semiconductor element is mounted on top of it as in (a) There is no interference. Therefore, also by this method, a large-capacity resin-sealed semiconductor device in which two identical semiconductor elements are embedded in the same direction as in (a) can be obtained.

(C) Since each semiconductor element and its corresponding lead are sequentially laminated by the same action as in (b), a large-capacity resin containing a plurality of identical semiconductor elements is built by this method. A sealed semiconductor device is obtained.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a cross section of a resin-sealed semiconductor device which is a first embodiment of the present invention. The manufacturing method will be described below. First, the semiconductor element 1a with the circuit formation side facing up
A lead frame having a joint plate 2 having a smaller size than the semiconductor element 1a and having insulating members 5 on both surfaces and an assembly of leads 3 so that the electrode pads 1ap are exposed. Are mounted and joined, and the electrical connection (wire bonding) between the semiconductor element 1a and the lead 3 is performed by the wire 4. After that, the semiconductor element 1 is
Then, b is mounted with the circuit forming surface facing upward and bonded, and then electrically connected to the lead 3. This state is sealed with resin 6, and unnecessary portions of leads 3 are cut and molded. In addition,
As the insulating member 5 used here, a film having a thickness of about 100 μm, which is coated with an adhesive on both sides, is generally used.
Alternatively, an epoxy adhesive may be used.

FIG. 2 shows a part of the lead frame used in this embodiment, and the chain lines A, B and C show the outlines of the insulating member 5, the semiconductor element 1a (1b) and the resin 6, respectively. As described above, the electrode pad 1ap is provided between the chain lines B and C. When the insulating member 5 is interposed over the entire surface of the bonding plate 2 as shown in this figure, if there is a possibility that reliability may be deteriorated such as generation of air bubbles inside the adhesive layer of the insulating member 5, the insulating member 5 may be used. It is recommended to divide it so that the required minimum area is obtained.

FIG. 3 shows a part of the lead frame of the second embodiment of the present invention, in which electrically ineffective leads are provided in place of the joining plate 2 of the previous embodiment.

In a resin-sealed semiconductor device such as a memory package, when soldering to a printed circuit board,
A method called reflow is often used. This is because the entire device is exposed to a high temperature of about 230 to 240 ° C., the atmospheric moisture contained in the resin 6 exceeds an allowable value, the device contains an easily expandable member such as an insulating film, or a member. If peeling occurs, the resin 6 may be cracked at this time.

According to this embodiment, the area of the insulating member (film) can be reduced, and at the same time, the semiconductor element 1a (1b) can be reduced.
In addition, since the area where the resin 6 adheres directly increases and the adhesive strength improves, it is effective in preventing cracks.

FIG. 4 shows a cross section of a resin-sealed semiconductor device which is a third embodiment of the present invention. A step is provided in a portion (internal lead) embedded in the resin 6 of the lead 3, and wire bonding is performed at a step different from each of the semiconductor elements 1a and 1b. When the wire 4 is likely to come into contact with the corner portion of the semiconductor element when the first embodiment is used, such means may be adopted. The internal leads do not necessarily have to be bent at a right angle as shown in the drawing, but may have a minimum level difference so that the effect can be obtained. The bus bar 3ag in the figure is a common lead for power supply or grounding.

FIG. 5 shows a cross section of a resin-sealed semiconductor device which is a fourth embodiment of the present invention. The manufacturing method will be described below. First, the semiconductor device 1a with the circuit formation side facing up
Is mounted, a lead frame having a shape in which the electrode pad 1ap is exposed and having an assembly of leads 3a having insulating members 5 on both sides is mounted and bonded, and the wire 4 is used as a semiconductor element. Electrical connection is made between the lead 1a and the lead 3a. After that, the semiconductor element 1b having the circuit forming surface facing upward from the upper portion of the lead 3a and the lead frame having the assembly of the leads 3b are mounted and bonded, and the semiconductor element 1b is connected by the wire 4.
Is electrically connected to the lead 3b. Then, the leads 3a and 3b are electrically joined, the lead 3b is cut and molded,
These are sealed with resin 6, and unnecessary portions of the leads 3a are cut and molded. Alternatively, as another manufacturing method, each of the semiconductor elements 1a and 1b may be electrically connected in advance, and then both of them may be laminated and joined together. The F portion in the figure has a smaller flow path for the resin 6 in the resin sealing step than the other portions, but normally there is no particular problem with respect to resin fluidity. However, for example, in the case of a product in which the pitch of the leads 3 is fine or the shape is complicated, there is a possibility that the resin 6 will not flow into this portion in some cases. It is advisable to take measures such as sealing with.

FIG. 6 shows a part of the lead frame used in this embodiment, and chain lines A, B and C respectively show the contours of the insulating member 5, the semiconductor element 1a (1b) and the resin 6. The electrode pad is provided in the central portion of the semiconductor element along the longitudinal direction.

FIG. 7 shows an electrical connection portion of the same embodiment (F in FIG. 5).
Part) is enlarged. Loop height of wire 4 hr
Is usually about 200 to 300 μm, while lead 3
a and the sum of the thicknesses of the insulating members 5 on both sides thereof Tl + Ts1 + T
Since s2 is about 400 μm, the semiconductor element 1 is on the upper side.
The wire 4 does not interfere even when b is loaded. Also,
If the portion of the lead 3a that contacts the wire 4 is made thinner than the other portions as shown in this figure, the effect is further improved.

FIG. 8 shows a cross section of a resin-sealed semiconductor device which is a fifth embodiment of the present invention. Lead 3a
The height of the lead 3 is outside the semiconductor element 1a.
There is a step so that it is the same as b, and both are wire 4
It is electrically connected with. In the present invention, since the semiconductor element and the internal lead are firmly joined via the insulating member 5,
The leads do not necessarily have to be mechanically joined by a brazing material or welding, and it suffices if electrical conduction is obtained in this way. Further, the step provided on the lead 3a does not have to be adjusted to the height of the lead 3b in particular, and may be bent so as not to impair the accuracy of the electrical connection position.

FIG. 9 shows a cross section of a resin-sealed semiconductor device which is a sixth embodiment of the present invention. The lead 3a has a step on the upper surface of the semiconductor element 1a. By doing so, the distance between the two semiconductor elements, that is, the semiconductor element 1
Since it is possible to increase the height of the electrical connection portion between a and the lead 3a, it is possible to prevent the semiconductor element 1a from interfering with the wire 4, and omit the thinning of the inner lead as in the embodiment. You can

FIG. 10 shows a cross section of a resin-sealed semiconductor device which is a seventh embodiment of the present invention. The structure is similar to that of the fifth embodiment, but four semiconductor elements are incorporated in the package. According to the present invention, such a large number of semiconductor elements can be incorporated by repeating the basic manufacturing process. Further, in this figure, an example in which the semiconductor elements are bonded to both sides of the lead is shown, but in addition to this, three or more semiconductor elements can be incorporated by the method of using the bonding plate as in the first embodiment.

[0031]

According to the present invention, since two or three or more identical semiconductor elements can be mounted and electrically connected in the same direction, they have a large capacity and are suitable for simplification of the process, and solder mounting. It is possible to obtain a resin-sealed semiconductor device having excellent reliability in a high-pitched sound environment.

[Brief description of drawings]

FIG. 1 is a sectional view of a resin-sealed semiconductor device that is a first embodiment of the present invention.

FIG. 2 is a plan view of a part of the lead frame shown in FIG.

FIG. 3 is a plan view of a part of the lead frame of the second embodiment of the present invention.

FIG. 4 is a sectional view of a resin-sealed semiconductor device that is a third embodiment of the present invention.

FIG. 5 is a sectional view of a resin-sealed semiconductor device that is a fourth embodiment of the present invention.

FIG. 6 is a plan view of a part of the lead frame of the fourth embodiment.

FIG. 7 is a sectional view of an electrical connection portion of a resin-sealed semiconductor device of a fourth embodiment.

FIG. 8 is a sectional view of a resin-sealed semiconductor device that is a fifth embodiment of the present invention.

FIG. 9 is a sectional view of a resin-sealed semiconductor device that is a sixth embodiment of the present invention.

FIG. 10 is a sectional view of a resin-sealed semiconductor device that is a seventh embodiment of the present invention.

[Explanation of symbols]

1a, 1b ... Semiconductor element, 1ap ... Electrode pad, 2 ... Bonding plate, 3, 3a, 3b ... Lead, 3ag ... Bus bar, 4
... wire, 5 ... insulating member, 6 ... resin.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Maya Obata, 502 Jinritsucho, Tsuchiura City, Ibaraki Prefecture Inside the Hiritsu Manufacturing Co., Ltd. Mechanical Research Laboratory

Claims (20)

[Claims] 1. A resin-sealed semiconductor device comprising two semiconductor elements, a plurality of leads, a bonding plate for the semiconductor elements, an insulating member, and wires, which are sealed and molded with resin. After joining the bonding plate of the semiconductor element to the circuit forming surface of the one semiconductor element via the insulating member and making a predetermined electrical connection using a wire, the other surface of the bonding plate is connected via the insulating member to the other side. A resin-encapsulated semiconductor device characterized in that a non-circuit forming surface of one semiconductor element is joined, a predetermined electrical connection is made using a wire, and they are sealed and molded with a resin. 2. A resin-encapsulated semiconductor device comprising two semiconductor elements, a plurality of leads, an insulating member, and a wire, which are encapsulated and molded with a resin, on the circuit forming surface of each semiconductor element. Part of the vicinity of the semiconductor element of the lead is joined via an insulating member, and a predetermined electrical connection is made using a wire,
For any one of them, the lead is cut and removed from a predetermined portion and molded, and the non-circuit forming surface of the semiconductor element is joined to the lead of the other through an insulating member,
After electrically connecting the corresponding leads of both of them,
A resin-encapsulated semiconductor device characterized by encapsulating and molding them with resin. 3. A resin-encapsulated semiconductor device comprising a plurality of semiconductor elements, a plurality of leads, an insulating member, and a wire, which are encapsulated and molded with a resin to insulate the circuit forming surface of each semiconductor element. A part of the vicinity of the semiconductor element of the lead is joined through a member, a predetermined electrical connection is made using a wire, and one except one of them is cut and removed from a predetermined part, and molded, The remaining one of the leads is sequentially stacked and joined from the non-circuit forming surface of the semiconductor element via an insulating member, and all the corresponding leads are electrically joined, and then they are sealed with resin. A resin-encapsulated semiconductor device characterized by being molded and stopped. 4. The resin-encapsulated semiconductor device according to claim 1, wherein a portion of the lead, which is electrically connected to another by the wire, that is embedded in the resin after molding is bent at a plurality of locations. 5. The resin-sealed semiconductor device according to claim 2, wherein the lead joined to any of the semiconductor elements via the insulating member is an electrically effective lead. 6. The resin-sealed semiconductor device according to claim 3, wherein the lead joined to any one of the semiconductor elements via the insulating member is an electrically effective lead. 7. The resin-sealed semiconductor device according to claim 2, wherein the lead joined to any one of the semiconductor elements via the insulating member is an electrically ineffective lead. 8. The resin-sealed semiconductor device according to claim 3, wherein the lead joined to any of the semiconductor elements via the insulating member is an electrically ineffective lead. 9. The resin-sealed semiconductor device according to claim 2, wherein a portion of the lead electrically connected to the semiconductor element by the wire is thinner than other portions. 10. The lead according to claim 3,
A resin-sealed semiconductor device in which a portion electrically connected to a semiconductor element by the wire is thinner than other portions. 11. The resin-encapsulated semiconductor device according to claim 1, having a portion in which a resin used for encapsulation is interposed between a circuit forming surface of the semiconductor element and a joining plate joined thereto. 12. A resin-sealed semiconductor device according to claim 2, wherein a resin used for sealing is interposed between a circuit forming surface of the semiconductor element and a lead joined thereto. 13. The resin-encapsulated semiconductor device according to claim 3, wherein a portion in which the resin used for encapsulation is interposed is provided between the circuit formation surface of the semiconductor element and the lead joined thereto. 14. The resin-sealed semiconductor device according to claim 1, wherein the two semiconductor elements are separated by at least 200 μm or more. 15. The resin-sealed semiconductor device according to claim 2, wherein the two semiconductor elements are separated from each other by at least 200 μm or more. 16. The semiconductor device according to claim 3, wherein at least 200 from the certain semiconductor element to the semiconductor element closest thereto.
A resin-encapsulated semiconductor device separated by at least μm. 17. The resin-sealed semiconductor device according to claim 1, wherein the two built-in semiconductor elements are the same. 18. The resin-encapsulated semiconductor device according to claim 2, wherein the two built-in semiconductor elements are the same. 19. The resin-sealed semiconductor device according to claim 3, wherein all the built-in semiconductor elements are the same. 20. The resin-sealed semiconductor device according to claim 1, wherein the plane area of the one semiconductor element is larger than that of the bonding plate.