JPH0823048A - P/b-lcc type semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the positional deviation of a plurality of PCB-LCC substrates to be mounted by a method wherein each electrode pad of a Print/ Board-Leadless Chip Carrier (P/B-LCC) type semiconductor device is formed into the shape with which they are fitted with each other. CONSTITUTION:A wiring and an electrode, on the side where a semiconductor chip is mounted, and a recessed electrode pad 2 (Cu) on the opposite side of the above-mentioned side, or a protruding electrode pad 4 (Cu) are provided respectively on a Print/Board-Leadless Chip Carrier (PCB-LCC) substrate 1. The protruding electrode pad 4 and the recessed electrode pad 2 are opposingly fitted, and they are connected by soldering. As above-mentioned, the electrode pads are fixed and connected by soldering when the PCB-LCC substrate 1 is mounted, and their positional deviation can be prevented.

Description

Detailed Description of the Invention

[0001]

The present invention relates to P / B-LCC (Pr
int / Board-Leadless Chip Ca
and a P / B-LC
The present invention relates to a technique effectively applied to a C substrate.

[0002]

2. Description of the Related Art A conventional P / B-LCC substrate will be described in detail with reference to FIGS.

FIG. 3 is a bird's-eye view for explaining the electrode pads of the P / B-LCC substrate, and FIG. 4 is the P / B thereof.
FIG. 6 is a diagram for explaining solder connection between electrode pads of an LCC substrate.

In FIGS. 3 and 4, 1 is a P / B-LC
C substrate, 3 is solder, and 5 is a conventional electrode pad, respectively.

As shown in FIG. 3, the electrode pad 3 in the conventional P / B-LCC substrate has a via hole for the electrode which penetrates the P / B-LCC substrate for electrically connecting to the chip mounting surface side. It is provided from one end of the pad 3, and the solder connection portion of the electrode pad 3 is flat.

Further, at the time of loading, as shown in FIG. 4, the flat surfaces of the electrode pads are connected to each other by soldering.

[0007]

DISCLOSURE OF THE INVENTION The present inventors have found the following problems as a result of examining the above prior art.

There is a problem in that the solder connection portion of the electrode pad of the conventional P / B-LCC substrate is a flat surface, and the flat surfaces are solder-connected to each other at the time of loading, which causes a positional deviation.

An object of the present invention is to load a plurality of P / B-
It is an object of the present invention to provide a technique capable of preventing positional deviation on an LCC substrate.

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

[0011]

Of the inventions disclosed in the present application, a representative one will be briefly described below.
It is as follows.

A semiconductor chip is mounted on a printed wiring board, electrode pads are provided on the surface opposite to the mounting surface, and metal-plated via holes penetrating the printed wiring board from one end of the electrode pads are provided. P / B on which a plurality of P / B-LCC type semiconductor devices in which wirings on the chip mounting surface and electrode pads are electrically connected are stacked
-In the LCC type semiconductor device, the electrode pads of the P / B-LCC type semiconductor device are shaped to fit together.

[0013]

According to the above means, the semiconductor chip is mounted on the printed wiring board, the electrode pad is provided on the surface opposite to the mounting surface, and the printed wiring board is penetrated from one end of the electrode pad. In a P / B-LCC type semiconductor device in which a plurality of P / B-LCC type semiconductor devices in which wirings on the chip mounting surface and electrode pads are electrically connected by mounting metal-plated via holes are loaded, By forming the electrode pads of each of the plurality of P / B-LCC semiconductor devices to be fitted to each other, the electrode pads of the P / B-LCC substrates are fitted and fixed. Since it is connected by soldering, it is possible to prevent positional deviation.

The structure of the present invention will be described below together with embodiments.

In all the drawings for explaining the embodiments, parts having the same function are designated by the same reference numerals, and the repeated description thereof will be omitted.

[0016]

FIG. 1 is a diagram for explaining electrode pads of two P / B-LCC substrates to be laminated, which is an embodiment of the present invention. In FIG. 1, 1 is a P / B-LCC substrate,
Reference numeral 2 denotes a concave electrode pad (Cu), and 4 denotes a convex electrode pad (Cu).

The P / B-LCC substrate 1 of this embodiment is shown in FIG.
As shown in FIG. 3, wirings and electrodes (not shown) on the side on which the semiconductor chip is mounted and electrode pads 3 are provided on the surface opposite to the wirings and electrodes, and the electrode pads 3 have a convex shape 2
And the concave type 4.

The method of forming the convex and concave electrode pads 4 and 2 is, for example, that a conductor is formed on the surface of the substrate, the thick portions of the convex and concave portions are formed by etching, and the thin portion is masked. In contrast to this method, the method of forming by plating and the like, and the opposite method of forming the convex and concave thin portions of the electrode pad by etching after masking with a resist and masking the thick portion and plating Can be mentioned. However, the method is not limited to this.

Next, the solder connection between the electrode pads of the P / B-LCC substrate 1 of this embodiment will be described in detail with reference to FIG.

FIG. 2 is a partially enlarged view for explaining the solder connection between the electrode pads of the P / B-LCC substrate of this embodiment. In FIG. 2, the shaded portion 3 indicates solder.

As the electrode pads of the P / B-LCC substrate of this embodiment, the convex electrode pads 4 and the concave electrode pads 2 shown in FIG. 1 are fitted face-to-face as shown in FIG. Make solder connections.

The solder connection at this time is performed, for example, by performing solder printing on one of the electrode pads in advance and by reflowing or the like.

As described above, when the P / B-LCC substrate 1 of this embodiment is loaded, the electrode pads are fixed by soldering by making the electrode pads into a convex shape and a concave shape in which they are fitted to each other. Since they are connected, it is possible to prevent positional deviation.

Further, the solder connection of the convex and concave electrode pads 4 and 2 on the P / B-LCC substrate 1 of this embodiment is as shown in FIG.
In the above, an example was given in which solder was applied to the entire connection surface, but by reducing the amount of solder and applying solder only to the central portions of the convex and concave parts to connect, even if solder flow occurs, the peripheral pads Can be prevented.

For the solder connection of the convex and concave electrode pads 4 and 2 on the P / B-LCC substrate 1 in the present embodiment, in the case of a device with high power, solder is applied to the entire surface to connect the leads. (Pad for electrode) When the pitch becomes narrow, it is better to reduce the amount of solder and apply solder only to the central portion for connection.

Further, in the P / B-LCC substrate 1 according to the present invention, the contact area can be made larger than before by connecting the electrode pads in three-dimensional contact by soldering during loading. Become stronger.

As described above, the invention made by the present inventor is
Although the present invention has been specifically described based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

[0028]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

By forming the electrode pads of the plurality of P / B-LCC type semiconductor devices to be stacked with each other, the electrode pads of the P / B-LCC substrates are fitted together. Fixed and soldered,
It is possible to prevent positional deviation.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an electrode pad of a P / B-LCC substrate which is an embodiment of the present invention.

FIG. 2 is a partially enlarged view for explaining solder connection between electrode pads of the P / B-LCC substrate of the present embodiment.

FIG. 3 is an overhead view for explaining a conventional P / B-LCC substrate.

FIG. 4 is a diagram for explaining solder connection between electrode pads of a conventional P / B-LCC substrate.

[Explanation of symbols]

1 ... P / B-LCC substrate, 2 ... Convex electrode pad, 3 ...
Solder, 4 ... Recessed electrode pad, 5 ... Conventional electrode pad.

Claims (2)

[Claims] 1. A semiconductor chip is mounted on a printed wiring board, an electrode pad is provided on a surface opposite to the mounting surface, and a metal-plated via hole penetrating the printed wiring board from one end of the electrode pad. P / B on which a plurality of P / B-LCC type semiconductor devices in which wirings on the chip mounting surface and electrode pads are electrically connected are stacked.
-The LCC type semiconductor device is characterized in that the electrode pads of the P / B-LCC type semiconductor device are shaped to fit with each other.
/ B-LCC type semiconductor device. 2. The loading P / B- according to claim 1.
In the LCC type semiconductor device, the fitting shape is a convex shape and a concave shape, and the P / B-LCC type semiconductor device is characterized.