JP2541532B2 - Semiconductor module - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-sealed semiconductor device and an electronic device using the same, and more particularly, to a single in-line package type module and a resin-sealed resin used therein. The present invention relates to a technology effective when applied to a semiconductor device of the type.

[Prior art]

Generally, in the entire structure of a resin-sealed type (resin mold type) semiconductor device, a semiconductor chip is mounted on a tab, and an electrode (pad) of this semiconductor chip and an internal lead portion of a lead are electrically connected by a wire. After that, it is molded with resin.

[Problems to be solved by the invention]

When a plurality of such resin mold type semiconductor devices are mounted on both sides of a wiring board to form a single in-line package (hereinafter referred to as SIP) type module,
The wiring layout on the wiring board becomes complicated because the signal terminals of the semiconductor device are opposite to each other on the front and back sides, and the number of wiring layers increases. Therefore, the same signal terminals are arranged on the front and back surfaces of the board, and the leads of the resin mold type semiconductor device are bent in reverse to form lead terminals (pads) on both the front and back sides.
It is possible to make the positions of the same. A semiconductor module to which this idea is applied is disclosed in, for example, JP-A-60-
There is one as described in 200559.

However, for example, plastic lead chip carrier type package (hereinafter referred to as PLCC)
In the case of mounting the semiconductor device of, the package is not symmetrical in the thickness direction with respect to the lead, that is, the thickness between the back surface of the package on the side where the external lead is bent and the internal lead. The size of the package in which the external lead is bent to one side and the package in which the external lead is bent to the opposite direction are different from each other. Therefore, it is necessary to change the dimensions of the lead frame according to the direction in which the external leads are bent. Also, the PL of the wiring board
Since other electronic element components such as chip capacitors (for decoupling) are mounted under the CC type semiconductor device, simply bending the leads backwards will cause the package to contact the electronic element. The inventor found a problem that it could not be implemented. The so-called PLCC (Plasti
c Leaded Chip Carrier) type semiconductor device,
For example, Nikkei McGraw-Hill Inc., published June 11, 1984,
"Nikkei Electronics Separate Volume, Micro Devices"
(P148 to P153)

An object of the present invention is to provide a resin-encapsulated semiconductor which is effective when applied to an electronic device in which a plurality of semiconductor devices are mounted on both surfaces of a wiring board and other electronic elements are mounted under each semiconductor device. It is in.

Another object of the present invention is to provide a technique capable of forming a common wiring with only through-hole wiring in an electronic device in which a plurality of semiconductor devices are mounted on both surfaces of a wiring board.

The above and other objects and novel features of the present invention are as follows.
It will be apparent from the description of this specification and the accompanying drawings.

[Means for solving problems]

The outline of a typical invention disclosed in the present application is briefly described as follows.

That is, in the semiconductor module of the present invention, the external leads, which are respectively connected to the internal leads and project to the outside of the package, are bent toward the back surface of the package, and the thickness between the back surface of the package and the internal leads is adjusted to the surface of the package. A first semiconductor device having a thickness smaller than the thickness between the inner lead and the inner lead, and the first semiconductor device has a semiconductor chip mounted on the surface side of the inner lead,
In this semiconductor device, a semiconductor chip is mounted on the back surface side of the internal leads. One of the first semiconductor device and the second semiconductor device has an external lead on one side of the front and back surfaces of a double-sided mounting wiring board having signal terminals connected to the same position on the front and back sides through through-hole wiring. The first semiconductor device and the second semiconductor device are mounted on the other surface of the front and back surfaces of the double-sided mounting wiring board by connecting their external leads and signal terminals. ing.

[Action]

According to the above-mentioned means, the first semiconductor device is mounted on one surface of the double-sided mounting wiring board having the signal terminals connected through the through-hole wiring at the same positions on the front and back surfaces, and the second semiconductor is mounted on the other surface. Since the same signal terminal is arranged at the same position on both front and back surfaces of the wiring board by mounting the device to form a semiconductor module, it is possible to connect only through holes to form a common wiring. Wiring on the board can be done easily. Further, since the area for wiring can be reduced, the number of wiring layers can be reduced.

Example of Invention

An embodiment of the present invention will be specifically described below with reference to the drawings.

In all the drawings for describing the embodiments, components having the same function are denoted by the same reference numerals, and their repeated description will be omitted.

FIG. 1 is a sectional view showing a schematic configuration of a PLCC type semiconductor device according to an embodiment of the present invention.

As shown in FIG. 1, the PLCC type semiconductor device of this embodiment has a semiconductor chip 1 mounted under a substrate (tab substrate) 2, that is, on the back surface side of an internal lead 3A of a lead 3, and an electrode of the semiconductor chip 1 After the wire 4 for electrically connecting the (pad) and the internal lead 3A of the lead 3 is bonded, it is molded with a resin to form a package 5. The outer lead 3B of the lead 3 is bent inward. That is, it is a semiconductor device in which the semiconductor chip 1 is mounted on the thinner side with respect to the leads 3 of the package 5, and in the upper and lower surfaces of the package 5 in FIG. Is the back surface 5B of the package 5, and the opposite surface is the front surface 5A. Since the semiconductor chip 1 is mounted on the back surface side of the internal lead 3A, it is a second semiconductor device.

Moreover, the PLCC type semiconductor device shown in FIG.
1 is a semiconductor device having a semiconductor chip mounted on the tab 2 of the PLCC semiconductor device shown in FIG. 1, that is, on the surface side of the internal lead. That is, it is a semiconductor device in which the semiconductor chip 1 is mounted on the thicker side with respect to the leads 3 of the package 5, and the surface on the side where the external lead 3B is bent, of the upper and lower surfaces of the package 5 in FIG. Is the back side 5B of the package 5, and the opposite side is the front side.
Since the semiconductor chip 1 is mounted on the front surface side of the internal lead 3A, it is a first semiconductor device.

In addition, as shown in FIGS. 3 and 4 (plan views showing the schematic configuration of the front and back surfaces of the printed wiring board of the SIP module), the printed wiring board 10 of the SIP module has a front surface 11 and a back surface 12 respectively. Signal terminals (pads) 13 for wiring for electrically connecting the external leads of the semiconductor device, connection terminals (pads) 14 for attaching lead pins, and connection terminals 15 for mounting chip capacitors (decoupling capacitors) are provided. Each is provided. The same signal terminals 13 of the semiconductor device mounted on the front surface 11 and the semiconductor device mounted on the back surface 12 are connected to the printed wiring board 10.
It is provided so that it comes to the same position on both front and back sides. Further, since the same signal terminals 13 on the front surface 11 and the back surface 12 are located at the same positions on both front and back surfaces, they are connected only by through-hole wiring (not shown) to form a common wiring.

Then, as shown in FIG. 5 (a cross-sectional view of the main part of the SIP module), the chip capacitor 16 is mounted on the connection terminal 15 of the printed wiring board 10 on which the signal terminal 13 and the connection terminals 14 and 15 are thus provided. Then, on the signal terminal 13 on the surface 11 of the printed wiring board 10, the semiconductor chip 1 is mounted on the signal terminal 13 on the surface 11 of the printed wiring board 10 in the thinner direction with reference to the leads 3 of the package 5.
The semiconductor device 17 is mounted with the first semiconductor device 18 in which the semiconductor chip 1 is mounted on the signal terminal 15 on the back surface 12 on the thicker side from the lead 3 of the package 5 as a base point, and the SIP module is configured. It

As described above, the second semiconductor device 17 having the semiconductor chip 1 mounted on the thinner side of the lead 3 of the package 5 is manufactured, and the semiconductor device 17 is mounted on the printed wiring board.
A SIP module (electronic device) having a first semiconductor device 18 mounted on the front surface 11 of 10 and a semiconductor chip 1 mounted on the back surface 12 with the thicker one based on the leads 3 of the package 5 is configured. By doing so, since the same signal terminal 13 is provided at the same position on both front and back surfaces of the printed wiring board 10, it is possible to form a common wiring by connecting only through-hole wiring. Wiring is easy. Further, since the area for wiring can be reduced, the number of wiring layers can be reduced.

Further, as described above, the semiconductor chip 1 is simply attached to the lower side of the tab 2 and set in a normal mold cavity for resin molding. Therefore, with the first semiconductor device 18 in which the semiconductor chip 1 is mounted on the front surface side of the internal lead 3A and the second semiconductor device 17 in which the semiconductor chip 1 is mounted on the back surface side of the internal lead 3A, the entire package 5 is Of the same size and each package 5
The thickness between the back surface of the internal lead 3A and the inner lead 3A, that is, the thickness of the thinner lead is the same, and the opposite is the same. Becomes
Since normal cutting and molding can be performed as they are, it is possible to reverse the terminal positions without changing the conventional equipment, devices, and processes, that is, to make packages that are mirror-symmetric to each other.

As mentioned above, although the present invention was explained concretely based on an example, the present invention is not limited to the above-mentioned example.
It goes without saying that various modifications can be made without departing from the spirit of the invention.

In the above embodiments, the present invention is applied to the PLCC semiconductor device, but the present invention can be applied to all resin-sealed semiconductor devices.

〔The invention's effect〕

The following is a brief description of an effect obtained by the representative one of the inventions disclosed in the present application.

First semiconductor chip mounted on the surface side of the internal lead
And the second semiconductor device in which the semiconductor chip is mounted on the back surface side of the internal lead, and the external lead is bent toward the back surface of each package to form a lead terminal, and the same position is formed in the through hole. Since the first semiconductor device is mounted on one surface of the double-sided mounting type wiring board on which the signal terminals are provided, and the second semiconductor device is mounted on the other side thereof, the double-sided mounting type wiring board is formed. Since the same signal terminals are arranged at the same positions on both front and back sides, the common wiring can be configured by connecting only through-hole wiring, so that the wiring on the wiring board can be simplified. Further, since the area for wiring can be reduced, the number of wiring layers can be reduced. Furthermore, since the leads of the first semiconductor device and the leads of the second semiconductor device can be manufactured using the same type of lead frame, the first semiconductor device and the second semiconductor device can be manufactured using one type of lead frame. A semiconductor device can be manufactured, and a semiconductor module can be manufactured efficiently at low cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing a schematic configuration of a PLCC type second semiconductor device, and FIG. 2 is a sectional view showing a schematic configuration of a PLCC type first semiconductor device. 3 is a plan view showing a front surface of a printed wiring board of a SIP type semiconductor module, FIG. 4 is a plan view showing a back surface of a printed wiring board of a SIP type semiconductor module, and FIG. 5 is a SIP type semiconductor. It is a principal part sectional drawing of a module. In the figure, 1 ... semiconductor chip, 2 ... tab, 3 ... lead, 3A ... internal lead, 3B ... external lead, 4 ... wire, 5 ... package, 5A ... package surface, 5B ...
… Backside of package, 10 …… Printed wiring board (double-sided mounting type wiring board), 11 …… Front surface of printed wiring board, 12…
… The back of the printed wiring board, 13 …… Signal terminals, 14,15…
... connection terminal, 16 ... chip capacitor, 17 ... second semiconductor device, 18 ... first semiconductor device.

Claims (4)

(57) [Claims] 1. An outer lead, which is continuous with an inner lead and protrudes outward of a package, is bent toward a back surface of the package, and a thickness between the back surface of the package and the inner lead is set to a surface of the package. The first semiconductor device is formed to be thinner than the thickness between the inner leads, and the semiconductor chip is mounted on the front surface side of the inner leads, and the outer leads that are continuous with the inner leads and project to the outside of the package. And the semiconductor chip is formed so that the thickness between the back surface of the package and the internal lead is thinner than the thickness between the front surface of the package and the internal lead. Both the second semiconductor device mounted on the board and the signal terminal connected through through-hole wiring at the same position on both front and back surfaces. A mounting wiring board, and one of the first semiconductor device and the second semiconductor device is connected to one of the front and back surfaces of the double-sided mounting wiring board by connecting the external lead and the signal terminal. On the other hand, on the other side of the front and back surfaces of the double-sided mounting wiring board, the first
2. A semiconductor module in which the other of the semiconductor device and the second semiconductor device is mounted by connecting its external lead and the signal terminal. 2. The semiconductor module according to claim 1, wherein a plurality of the respective semiconductor devices are mounted on both front and back surfaces of the double-sided mounting wiring board. 3. Each of the semiconductor devices is a single
The semiconductor module according to claim 1 or 2, which is an in-line package type semiconductor device. 4. The semiconductor module according to any one of claims 1 to 3, wherein each of the semiconductor devices is a plastic read chip carrier type semiconductor device.