JPS6240442Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a semiconductor device.

Resin packages are used in semiconductor devices such as transistors, diodes, and IC circuits, and in this case, the pulled out terminals are formed across the sides and back of the package, making it leadless. There is something. When loading this semiconductor device onto a printed circuit board, the terminal section formed on the back side of the package is brought into direct contact with the conductive foil on the printed circuit board, and the terminal section formed on the side surface of the package and the conductive foil are soldered. I try to do that.

FIG. 3 shows the soldering state described above, where 1 is a printed circuit board, 2 is a conductor foil, 3 is a package, and 4 is a terminal. The terminal 4 is connected to one surface of the package cage 3 (for example, this is the front surface) 3a
and the back surface 3b. When soldering, temporarily attach the package 3 to the surface of the printed circuit board 1 with adhesive so that the terminal portion along the back surface 3b is in contact with the conductor foil 2, and then turn the printed circuit board 1 over as shown in the figure and attach the package 3 to the surface of the package 3. 3c is facing downward and is immersed in the solder 5 as it is.

However, when dipping into the solder 5 as described above, the surface 3c of the package 3 is pressed against the solder 5 and comes into contact with the solder 5 because the resin that makes up the package 3 is difficult to wet with solder regardless of its type. However, on each of the surrounding surfaces, the closer the printed circuit board 1 is, the more difficult it is for the solder to approach the printed circuit board 1, and there are spaces 6 where no solder adheres. Therefore, the closer the position of the terminal 4 is to the center of the front surface 3a of the package 3, the less the solder approaches the terminal 4, which makes it extremely difficult to solder the terminal 4 and the conductor foil 2. Such a phenomenon appears conspicuously when the package 3 is extremely small (for example, about 2 to 3 mm in width and 1 to 2 mm in height).

The purpose of this invention is to ensure reliable soldering between the terminal and the conductive foil.

An example of this invention will be explained with the help of diagrams: 1
1 is a resin package of a semiconductor device, 12 is a terminal on the front side 11a of the package 11, and 13 is a terminal on the back side. Terminal 12 is package 1
1 and a terminal portion 12b along the back surface 11b of the package 11. The above-described formation of the terminal 12 is not much different from the conventional one, but in this invention, the terminal portion 1
A terminal portion 12c is formed from 2a to extend laterally when viewed from the front of the package 11.

When soldering, the package 11 is temporarily attached to the printed circuit board 1 by gluing its back surface 11b with an adhesive or the like, so that the terminal portion 12b is in direct contact with the conductor foil 2, and the printed circuit board 1 is turned over. The package 11 is immersed in the solder 5 with the surface 11c facing downward. These things are no different from the conventional case.

However, at this time, the surface 11c is pressed against the solder 5, so that the end of the terminal portion 12c comes into contact with the solder 5, as shown in FIG. Since the terminal 12 is made of metal, the package 1
Since the solder 5 is much more easily wetted by solder than the resin composing the solder 1, the solder 5 easily flows from the terminal portion 12c to the terminal portion 12a. As a result, the solder 5 comes into full contact with the terminal portion 12a. As a result of the above, the terminal portion 12
This ensures that a and the conductive foil 2 are soldered together.

In this case, as shown in FIG. 1, the closer the terminal portion 12c is to the end surface 11c of the package 11, the more convenient it will be to contact the solder 55. Further, it is desirable that the terminal portion 12c extend close to the end surface 11d of the package 11. The above explanation was about the terminal 12, but the terminal 13 on the back side
It is also a good idea to extend it horizontally in the same way. 13c shows the extended terminal portion. Furthermore, if a terminal portion 12d is formed on the terminal 12 so as to extend over the surface 11c of the package 11,
When the terminal portion 12d comes into contact with the solder 5, the solder flows along the terminal portion 12d, and the solder flows to the terminal portion 12a.
It is convenient that it has become attached to .

As detailed above, according to this invention, soldering to the printed circuit board can be ensured through a simple configuration in which the terminals formed on the front of the package are extended laterally. be effective.

[Brief explanation of the drawing]

Figure 1 is a perspective view showing an embodiment of this invention;
The figure is a sectional view showing a soldered state, and FIG. 3 is a sectional view showing a conventional soldering state. 11...Package, 11a...Front, 11b
... Back side, 11c... Front side, 12... Terminal section, 1
2a, 12b...terminal part, 12c...extended terminal part.

Claims (1)

[Scope of utility model registration request] A semiconductor device comprising a resin package, in which terminals are formed across the front and back surfaces of the package, and the terminals are extended laterally on the front surface.