JPH0226098A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent a module substrate from cracking by a method wherein a portion which is likely to crack between the upper side of a module substrate and a latch hole is removed beforehand. CONSTITUTION:A latch hole 101 is made at a specific position on a module substrate 100 with a plurality of packages 1 mounted, and a latch 211 is made at a position corresponding to the latch hole 101 of a module substrate mounting socket 200 for standing and mounting the module substrate 100 on a mother board. At this time, a portion between a part of the rim of the latch hole 101 on the module substrate 100 and the upper side 103 of the module substrate 100 is removed. In other words, a portion between the upper side 103 of the module substrate 100 and the latch hole 101 where a crack is likely to occur is removed. This prevents the substrate from cracking.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a semiconductor device, and in particular, surface mounting is effective when applied to a semiconductor device equipped with a module board on which a plurality of mounting packages are mounted. It's about technology.

[Conventional technology]

For semiconductor devices, multiple mounting packages are first mounted on a module board, then this module board is installed in an upright module board mounting socket, and then the module board mounting socket is attached to a motherboard. There are some types of imposition that increase the mounting density of the mounting package by mounting and mounting (Published by Nikkei McGraw-Hill, Inc.).

Nikkei Electronics, September 7, 1987 issue, pp9
9-107). By the way, the surface mounting package has a rectangular shape when viewed from above, but if it is necessary to keep the height of the electronic device in which the motherboard is installed low, the surface mounting package has a rectangular shape when viewed from above. It is attached to the module board so that the long side is parallel to the motherboard.

The module board mounting socket is provided with a latch (claw) for fixing the module board when the module board is installed, and a latch hole is provided in the module board at a position corresponding to the latch. There is. That is, by latching the latch hole, the module board is fixed to the module board mounting socket. The module board is a so-called printed circuit board, and the latch hole is formed by drilling a hole in a predetermined portion of the module board with a drill, punch, or the like.

The diameter of the latch hole of the module board and the height from the center of the latch hole to the bottom when the module board is stood up are standardized, so that the sockets can be interchanged.

[Problem to be solved by the invention]

The inventor of the present invention investigated the latch hole of the module board and found the following problem.

That is, as described above, the diameter of the latch hole and the height from the center of the latch hole to the bottom when the module board is stood up are standardized and cannot be changed. Also, as mentioned above.

When keeping the height of an electronic device low, with surface mounting, the mounting package is mounted on the module board with it lying on its side, but in this case, the height from the bottom to the top of the module board when it is erected is also reduced. Therefore, the distance from the upper edge of the latch hole to the upper edge of the module board becomes smaller. For this reason, when a latch hole is drilled or punched in the module board, cracks are likely to form from the latch hole to the upper side of the module board. When cracks appear, the solder resist on the surface of the module board tends to peel off, causing moisture to enter and corrode the wiring inside.

An object of the present invention is to improve reliability of a semiconductor device by preventing cracks from forming in a module substrate.

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

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

That is, a latch hole is provided at a predetermined position of a module board on which a plurality of packages are mounted, and a latch is provided at a position corresponding to the latch hole of a module board mounting socket for mounting the module board upright on a motherboard. In the semiconductor device, the area from a part of the edge of the latch hole of the module substrate to the upper side of the module substrate is removed.

[Effect]

According to the above-described means, since the portion between the upper side of the module board and the latch hole where cracks are likely to form is removed in advance, it is possible to prevent cracks from forming in the module board. Thereby, the reliability of the semiconductor device can be improved.

[Embodiments of the invention]

A semiconductor device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view of a module board of a semiconductor device according to an embodiment of the present invention, FIG. 2 is a perspective view of a module board mounting socket into which the module board shown in FIG. 1 is installed, and FIG. FIG. 2 is an enlarged perspective view of a part of the module board shown in FIG. 1 and the socket for mounting the module board shown in FIG. 2;

In Figure 1, 1 indicates a mounted package (hereinafter referred to as a mounted package).
It is simply called a package) and is formed by resin molding a semiconductor chip.

Reference numeral 100 designates a module board (so-called printed circuit board) on which a plurality of the packages 1 are mounted, and is mainly made of epoxy resin, and although not shown, has a plurality of conductor wirings extending over its surface. The top is covered with a solder resist film. 105 is an electrode provided along the lower side 104 of the module board 100, and when the module board 100 is assembled into the module board mounting socket (hereinafter simply referred to as socket) 200 shown in FIG. This is the part connected to. Electrode 240 of socket 200 is connected to lead pin 230. The socket 200 is made of plastic. As shown in FIG. 1, the planar pattern of the package 1 is rectangular, and its long side is connected to the module board 10.
It is mounted on the module substrate 100 so as to be parallel to the upper side 103 or the lower side 104 of 0. 102 is an index to avoid making a mistake in the orientation when installing the module board 100 into the socket 200;
The orientation guide plate 212 shown in FIG. 3 is engaged here. 210 and 220 are module board 1
00, and the support member 210
and support members 220 are provided in pairs on each side of the socket 200. The orientation guide plate 2
12 is provided only on the support member 210 on the right side of the socket 200 shown in FIG. A latch 211 shown in FIG. 3 is provided on each supporting member 210 on both sides of the socket 200, and a latch hole 101 is provided in the module board 100 correspondingly. Then, when the module board 100 is assembled into the socket 200, the latch 211 engages the latch hole 101 and presses the module board 100 downward.

On the other hand, the support member 220 is provided with a protrusion preventing protrusion 221, which prevents the module board 100 from protruding forward. After the module board 100 is assembled into the socket 200, the lead pins 230 of the socket 200 are inserted into holes in a motherboard (not shown) for mounting. The module board 100 is mounted vertically on a motherboard. Note that the module board 100 shown in FIG. 3 shows the surface opposite to the surface on which the package 1 is mounted. 2 is an outer lead of package 1.

As shown in FIGS. 1 and 3, the latch hole 101 of this embodiment is formed into a U-shape by removing a portion 101A from a part of the edge to the upper side 103. That is, portions that are likely to crack due to stress or the like when forming the latch hole 101 are removed in advance. Since the latch hole 101 is U-shaped, its lower end is semicircular, and the socket 101 is located from the center of curvature.
The height h to the bottom edge of is standardized.

As described above, the latch holes 10 are located at predetermined positions on the module board 100 on which a plurality of packages 1 are mounted.
1, and a module board mounting socket 2 for mounting the module board 100 upright on a motherboard.
In a semiconductor device in which a latch 211 is provided at a position corresponding to the latch hole 101 of the module substrate 100, by removing a portion of the edge of the latch hole 101 of the module substrate 100 to the upper side 103 of the module substrate 100, the module Since the part between the upper side 103 of the substrate 100 and the latch hole 101 where cracks are likely to form is removed, cracks can be prevented from forming there. This prevents the solder resist film from peeling off, and prevents moisture from entering from the peeled portion of the solder resist film and corroding the conductor wiring, thereby improving the reliability of the semiconductor device.

Note that the latch hole 101 may have a shape as shown in FIGS. 4 to 6.

4 to 6 are plan views of a module board 100 that is different from the module board 100 shown in FIGS. 1 and 3. FIG.

The present invention has been specifically explained above based on examples, but
It goes without saying that the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the spirit thereof.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

Since no stress is applied between the upper side of the module board and the latch hole, cracks can be prevented from forming there. Thereby, the reliability of the semiconductor device can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a module board of a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a perspective view of a module board mounting socket into which the module board shown in FIG. 1 is installed. 3 is an enlarged perspective view of a part of the module board shown in FIG. 1 and the socket for mounting the module board shown in FIG. 2; FIG. 4 to 6 are plan views of a module board 100 that is different from the module board 100 shown in FIGS. 1 and 3. FIG. In the figure, 1... package, 100... module board. 101... Latch hole, 102... Index, 105... Electrode, 200... Socket, 210.
220...Supporting member, 240...Electrode, 211...
Latch, 221...Support protrusion, 212...Figure 2, Figure 1, Figure 3, Figure 4, Figure 5

Claims (1)

[Claims] 1. A semiconductor device comprising a latch hole provided at a predetermined position of a module board on which a plurality of packages are mounted, and a latch provided at a position corresponding to the latch hole of a module board mounting socket for mounting the module board upright on a motherboard. 2. A semiconductor device according to claim 1, wherein a portion of the module substrate from a part of the edge of the latch hole to the upper side of the module substrate is removed.