JPH02201945A - Surface mounting type semiconductor device - Google Patents

Abstract

PURPOSE:To make the gap between leads connected to the land on the same plane larger, avoid defective shorts by solder bridges, and enhance the reliability by connecting and fixing a first and a second lead to lands each disposed on different insulating boards. CONSTITUTION:A downward bend lead 7 is bent in parallel to the mounting surface of a base 2b on a land 5b, and a mounting section is formed. It is connected and fixed to the land 5b by a conductive adhesive 6 like solder. The front end of an upward bend lead 8 is connected and fixed to a land 5c by the adhesive 6 toward the land 5c in the vicinity of the top surface of a base 2c. With this construction, since a semiconductor chip 9 is mounted, leads 7, 8 of the semiconductor chip are connected to corresponding lands 5b, 5c, respectively, on two planes whose heights are different from each other. Thus, since the space between leads in the same plane is doubled, disadvantages such as solder bridge can be avoided, and the reliability is highly improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a surface-mounted semiconductor device in which a semiconductor chip is surface-mounted on an insulating substrate.

[Prior Art] FIG. 3 is a sectional view showing a conventional surface-mounted semiconductor device.

The wiring board 1a includes an insulating base material 2a, a wiring portion 3a, and a land portion 5.
a, solder resist 4a, and the like. This wiring board 1a is manufactured by the following method.

First, C11 is applied onto an insulating base material 2a such as glass epoxy.
A metal foil such as foil is crimped, and the metal foil is subjected to a treatment such as etching to form a wiring portion 3a and a land portion 5a of a predetermined shape. Next, a solder resist 4a is applied on the wiring part 3a.
Then, solder plating is performed on the land portion 5a. Thereby, the wiring board 1a is completed.

The semiconductor chip 9a is connected to a lead 15 from the side of its sealing portion.
a has been derived. This lead 15a is bent toward the mounting surface of the wiring board 1a near the sealing portion, and
It has a bent portion 16a that is bent parallel to the mounting surface near the mounting surface, and the portion formed parallel to the mounting surface is the part that is attached to the substrate 2a. and,
In this mounting, the semiconductor chip 9a is mounted on the wiring board 1a by adhering the part to the land part 5a of the wiring board 1a with an adhesive 6a such as solder and connecting it electrically and mechanically. ing.

[Problems to be Solved by the Invention] However, in the conventional surface-mounted semiconductor device described above, the leads 15a of the semiconductor chip 9a are all of the same length, and the leads 15a of the semiconductor chip 9a are mounted so that the parts are arranged on the same plane. Therefore, when surface mounting a semiconductor chip 9a with a narrow arrangement pitch of leads 15a, the adjacent
There is a problem in that solder enters between the bent portions 16a of the leads 15a, forming solder bridges, resulting in a short circuit between the leads 15a.

The present invention has been made in view of such problems, and includes:
It is an object of the present invention to provide a surface-mounted semiconductor device that can avoid short-circuit defects caused by solder bridges or the like.

[Means for Solving the Problems] A surface-mounted semiconductor device according to the present invention includes a first insulating base material having a plurality of land portions on its first surface, and a height position different from the first surface. The second surface has a plurality of lands on the second surface.
an insulating base material, and a semiconductor chip in which first leads bent downward and second leads bent upward are arranged alternately on the side of the sealing part, and the first lead of the semiconductor chip Either one of the leads and the second lead is connected to and fixed to the land portion of the first insulating base material, and the other lead is connected to and fixed to the land portion of the second insulating base material. It is characterized by being

[Function] In the present invention, a semiconductor chip is used in which first leads bent downward and second leads bent upward are arranged alternately on the side of the sealing part, and these leads are It is mounted by connecting to the land portion of the first insulating base material or the land portion of the second insulating base material.

Since the surfaces of the first and second insulating substrates on which the land portions are provided have different heights, the distance between the leads to be connected on the same plane is twice that of the conventional one, so the solder bridge etc. formation can be suppressed.

[Example] Next, an example of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a first embodiment of the present invention.

Insulating base material 2 such as glass epoxy or triazine resin
Wiring portions 3b and land portions 5b are formed in a predetermined wiring pattern on b. A base material 2c having an opening 10 of a size matching the semiconductor chip 9 to be mounted is laminated and fixed on the base material 2b. This base material 2C is also formed of an insulating material such as glass epoxy or triazine resin, like the base material 2b.

A wiring portion 3C is formed in a predetermined pattern on the base material 2c, and the wiring portion 3C is coated with a solder resist 4b. Furthermore, a land portion 5C is provided near the opening 10 of the base material 2C.

The wiring board 1b used in this embodiment is constructed as described above.

On the other hand, the semiconductor chip 9 used in this example is
Lower bent leads 7 bent downward in the vicinity of the sealing part by a lead bending die and upper bent leads 8 bent upward are arranged alternately on the side of the sealed part.

The downward bending lead 7 is bent on the land portion 5b parallel to the mounting surface of the base material 2b to form a mounting portion.
In this attachment, the part and the land part 5b are connected and fixed with a conductive adhesive 6 such as solder.

Further, the upper bent lead 8 is bent toward the land portion 5C near the upper surface of the base material 2c, and the tip portion is connected and fixed to the land portion 5C with an adhesive 6.

In this embodiment, the semiconductor chip 9 has the structure described above.
In order to mount the leads 7 and 8 of the semiconductor chip on the board 1
2,000 planes of the base material 2b and the base material 2C having different heights are connected to corresponding land portions 5b and 5c, respectively. As a result, the spacing between leads on the same plane is doubled compared to the conventional method, which avoids problems such as solder bridging when mounting semiconductor chips, resulting in extremely high reliability even for semiconductor chips with narrow lead spacing. It is possible to obtain a surface-mounted semiconductor device with high resistance.

Note that, in consideration of the mounting accuracy of the semiconductor chip 9, the opening 10 is preferably opened so that the wall surface of the opening 10 is bent downward and is separated from the tip of the door 7 by at least 0.5 mm. .

FIG. 2 is a sectional view showing a second embodiment of the invention.

Wiring portions 3d are formed in a predetermined pattern on the insulating base material 2e,
A land portion 5d and a land portion 5e are formed. The wiring portion 3d is coated with a solder resist 4c. The wiring board 1c is configured in this manner.

The raised terminal 11 has an upper layer terminal portion 13 formed on the upper surface of the insulating base material 2d, a lower layer terminal portion 14 formed on the lower surface, and electrical connection between the upper layer terminal portion 13 and the lower layer terminal portion 1-4 through the through hole 12. It is connected to The lower terminal portion 14 of this raised terminal 11 is connected and fixed to the land portion 5d with an adhesive 6 such as solder.

Similarly to the first embodiment, the semiconductor chip 9 has downwardly bent leads 7 and upwardly bent leads 8 which are bent downward or upward alternately in the vicinity of the sealing portion, and furthermore, the tips of each lead are bent downwardly or upwardly. The mounting surface is bent parallel to the mounting surface. The lower bent lead 7 is attached to the land portion 5e and fixed by adhesive 6, and the upper bent lead 8 is attached to the upper layer terminal portion 13 formed on the upper surface of the raised terminal 11. Connected and fixed.

In this embodiment, the semiconductor chip 9 has the structure described above.
Since this is implemented, short circuits between leads such as solder bridges can be avoided as in the first embodiment. Further, in this embodiment, since wiring can be provided also on the base material in the mounting area of the semiconductor chip, extremely high-density wiring can be performed.

[Effects of the Invention] As explained above, according to the present invention, a semiconductor chip in which the first leads bent downward and the second leads bent upward are arranged alternately on the side of the sealing part. Since the first lead and the second lead are connected and fixed to land portions provided on different insulating base materials using the same method, the distance between the land portions and the connected leads on the same plane is reduced. becomes extremely large. This avoids the occurrence of short circuit defects where adjacent leads are connected to each other by solder bridges, etc.
A highly reliable surface-mounted semiconductor device can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a first embodiment of the present invention, Fig. 2 is a sectional view showing a second embodiment of the invention, and Fig. 3 is a mounting structure of a semiconductor device by conventional surface mounting. FIG. 1a, lb, lc; wiring board, 2a, 2b, 2c, 2d
, 2e; Base material, 3a, 3b, 3c, 3d; Wiring portion, 4
a, 4b, 4c; solder resist, 5a, 5b, 5c
, 5d, 5e; Land portion, 6° 6a; Adhesive, 7; Downward bent lead, 8; Upward bent lead, 9.9a; Semiconductor chip, 10. Opening portion, 11; Raised terminal, 12; Through hole, 13; Upper layer terminal portion, 14; Lower layer terminal portion, 15
a; Lead, 16a; Bent part

Claims (1)

[Claims] (1) A first insulating base material having a plurality of lands on its first surface, and a second insulating base material having a plurality of lands on its second surface at a different height from the first surface. and a semiconductor chip in which first leads bent downward and second leads bent upward are arranged alternately on the side of the sealing part, and the first lead and the second lead of the semiconductor chip are arranged alternately. One of the two leads is connected to and fixed to the land portion of the first insulating base material, and the other lead is connected to and fixed to the land portion of the second insulating base material. A surface-mounted semiconductor device characterized by: