JPH05101854A - Hybrid integrated circuit device - Google Patents

Abstract

PURPOSE:To prevent generation of solder bridging between adjoining outer leads even though the pitch becomes small. CONSTITUTION:A group of terminal lands 20, 30 are mounted on the surfaces of a printed circuit board 11 alternately so that two adjoining ones are located on opposite sides, and a plurality of through holes 23, 33 are provided at the front side lands 21 and rear side lands 30. Outer leads 25, 35 are provided at the tips with insertion parts 26, 36, which are inserted in the through holes 23, 33. Because of this alternate arrangement of lands 20, 30, the pitche P of each group of lands becomes wider twice as large as in the conventional arrangement where all lands are located on the front side. Corresponding to the amount of this pitch widening, generation of solder bridging between adjoining lands can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid integrated circuit device, and more particularly to an improved outer lead mounting structure on a wiring board, which is effective for use in, for example, a computer module.

[0002]

2. Description of the Related Art As a hybrid integrated circuit device used in a computer module or the like, for example, there is one shown in FIG. That is, the hybrid integrated circuit device shown in FIG. 7 includes the wiring board 1, and the front and back surfaces of the wiring board 1 at one edge portion (hereinafter referred to as the lower edge portion) are a pair of front and back surfaces. A plurality of sets of terminal lands 2 and 2 are opposed to each other on the front and back sides, and are arranged in a row at equal pitches along the lower end side.

An outer lead 3 as a lead for ensuring electrical connection to the outside is arranged and soldered to each of the terminal lands 2 so as to be orthogonal to the lower end side. And in this hybrid integrated circuit device,
Each outer lead 3 is soldered to the terminal land 2 as follows.

That is, the outer lead 3 is preliminarily bent and formed with a substantially u-shaped clamp portion 4 at its upper end portion. Then, when the outer lead 3 is soldered to the terminal land 2, the clamp portion 4 of the outer lead 3 is inserted into the lower end side portion of the wiring board 1 from below, and the terminal lands 2 and 2 forming portions of the wiring board 1 are attached to the elastic portion. The outer leads 3 are tentatively fixed to the wiring board 1 by being sandwiched by the force from the front and back. In this state, the clamp portion 4 of the outer lead 3 is in contact with the terminal lands 2 and 2.

Thereafter, with the outer leads 3 temporarily fixed to the terminal lands 2 of the wiring board 1, the wiring board 1 is soaked (dipped) in its lower end side portion with a molten solder material (not shown). As a result, the soldering process is performed. By this soldering process, the outer leads 3
Since the soldering portion 5 is formed between the terminal land 2 and the terminal land 2, the outer lead 3 is electrically connected to the terminal land 2 and mechanically connected to the wiring board 1.

Examples of the hybrid integrated circuit device described above are disclosed in Japanese Patent Laid-Open No. 50-67962 and Japanese Utility Model Laid-Open No. 51-141356.

[0007]

However, in the hybrid integrated circuit device as described above, when the pitch dimension of the terminal land group, that is, the pitch dimension of the outer lead group becomes narrow, the adjacent terminal lands and the outer leads are adjacent to each other. It was revealed by the present inventor that there is a problem that a solder bridge is formed.

Therefore, by arranging the terminal lands on the front surface and the back surface of the wiring board 1 alternately at intervals of 1 pitch, the pitch of the terminal lands 2 on only one surface of the wiring board 1 (the same applies to the back surface). A measure to double the size can be considered. In this case, the outer lead 3 connected to the terminal land 2 on the front surface side and the outer lead 3 connected to the terminal land on the back surface side, and the outer leads 3 and 3 adjacent to each other are in a zigzag state in which the front and back sides are staggered. become.

However, in the hybrid integrated circuit device in which the outer leads 3 are alternately arranged on the front side and the back side of the wiring board 1 in this manner, the clamp portion 4 of the outer lead 3 holds the wiring board 1 from both sides of the front side and the back side. Therefore, the opposite side portion of the outer lead 3 connected to the front side terminal land 2 from the clamp portion 4 is located on the back side. That is, the terminal lands 2 adjacent to each other on the front side,
The clamp portion 4 of the outer lead 3 on the back side is located between the two. As a result, a solder bridge is formed between the front terminal land 2 and the outer lead 3 connected to the front terminal land 2, and the clamp portion 4 of the front outer lead 3.

It is an object of the present invention to provide a hybrid integrated circuit device capable of preventing the formation of a solder bridge between adjacent outer leads even when the pitch becomes narrow.

A second object of the present invention is to provide a hybrid integrated circuit device in which the outer leads can be securely fixed and placed on the terminal lands of the wiring board during the soldering process.

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.

[0013]

The typical ones of the inventions disclosed in the present application will be outlined below.

That is, a plurality of terminal lands are arranged in a line along one edge of the wiring board so as to be spaced apart from each other, and each terminal land is formed in a linear shape. In the hybrid integrated circuit device in which the formed leads are arranged so as to intersect the end side and soldered, the terminal land group is formed on the front surface and the back surface of the wiring board, and the adjacent land surfaces are formed on the front surface and the back surface. The wiring boards are arranged alternately, and a plurality of recesses are provided on the front surface and the back surface of the wiring board, respectively, arranged in the front surface side terminal land and the back surface side terminal land, respectively. The lead is characterized in that the insertion part is provided so as to project from a part thereof, and the insertion part is inserted into each of the recesses.

[0015]

According to the above-mentioned means, since the terminal lands are alternately arranged on the front surface and the back surface of the wiring board, the pitch dimension of the terminal land group on the front surface side and the pitch dimension of the terminal land group on the back surface side are Is twice as wide as in the case where all the terminal land groups are arranged in a line on the front surface side. Therefore,
As the pitch becomes wider, the occurrence of solder bridges between adjacent terminal lands can be prevented.

Since the lead is fixed by inserting the projecting insertion portion into the concave portion of the front side terminal land and the concave portion of the back side terminal land respectively, the fixing portion of the lead is opposite to that of the clamp portion. It is never exposed to the side. Therefore, unlike the case where the clamp portion is formed on the lead, the phenomenon that the pitch dimension of the front side lead is substantially halved by the back side lead does not occur.

Moreover, when the lead is soldered to the terminal land, the lead is prevented from floating by inserting the projecting insertion portion into the recess.
The leads will be soldered while being correctly positioned on the terminal lands.

FIG. 1 is a front view showing a hybrid integrated circuit device according to an embodiment of the present invention, FIGS. 2 (a), 2 (b), 2 (c),
(D) is a cross-sectional view taken along the line aa of FIG. 1, a cross-sectional view taken along the line bb, a partially cutaway enlarged partial front view of the c portion and a partially omitted side cross-sectional view thereof, and FIG. FIG. 4 is a front view showing a wiring board used in a method for manufacturing a circuit device, and FIG. 4 is a partially omitted perspective view showing the lead frame. FIG. 5 is a partially omitted perspective view showing a modified example of the lead frame.

In this embodiment, the hybrid integrated circuit device according to the present invention is configured to be used as a module of a computer. The hybrid integrated circuit device 10 includes a wiring board 11 formed in a rectangular plate shape, and the wiring board 11 includes an insulating board 12. The insulating substrate 12 is integrally formed by bonding two glass / epoxy plates 13 and a ceramic plate 14 sandwiched therebetween.

A front side electric wiring 15 and a back side electric wiring 16 are formed on the front surface and the back surface of the insulating substrate 12, respectively. The electric wiring is formed by a suitable method such as a method of forming a copper foil previously bonded to the wiring board 11 by applying a lithography process or a screen printing method. A plurality of semiconductor devices (hereinafter referred to as SOP ICs) 17 each having a small outline package are abutted on the front surface and the back surface of the wiring board 11 and mechanically connected by a reflow soldering process. And each SOP / IC17 has an electrical wiring 15 and 1
6 is electrically connected.

A terminal land (hereinafter referred to as a front side land) for mounting an outer lead is provided on one end edge (hereinafter referred to as a lower end side) of the surface 11a of the wiring board 11.
A plurality of 20 are arranged in a line along the lower edge with an equal pitch P. Further, a plurality of other terminal lands (hereinafter, referred to as backside lands) 30 are arranged in a line along the lower end side of the rear surface 11b of the wiring board 11 at a pitch P equal to that of the front side land 20 group. ing. And, the front land 20 group and the back land 3
The pitch P with the 0 group is shifted from each other by a half pitch Q. That is, the front side land 20 and the back side land 30 are staggered with a pitch Q which is half the pitch P of the front side land 20 and the back side land 30.

The respective lands 20 and 30 are the electric wiring 1
5 and 16, each is formed into a thin, substantially rectangular thin plate shape having a circular portion at the upper end. Each land 20 and 30 has an electric wiring 15,
16 are electrically connected to each other as appropriate.

The circular through hole 2 is formed in the circular portion 22 formed on the upper end of the rectangular portion 21 of the front side land 20.
3 is formed so as to penetrate the front and back surfaces of the wiring board 1, and the through hole conductor layer 24 is formed on the inner peripheral surface of the through hole 23 by a suitable means such as copper plating, for example, 10 μm to 15 μm. It is applied uniformly with a thickness of. Therefore, the inner diameter of the through hole 23 is equal to the thickness of the through hole conductor layer 24, that is, 20 μm to 30 μm.
The diameter is reduced by μm.

Similarly, the rectangular portion 3 of the back side land 30.
A circular through hole 33 is also formed in the circular portion 32 formed at the upper end of the wiring board 1 so as to penetrate the front and back surfaces of the wiring board 1. The through hole conductor layer is also formed on the inner peripheral surface of the through hole 33. 34 is uniformly applied with a predetermined thickness. Therefore, the inner diameter of the through hole 33 is reduced by the thickness of the conductor layer 34.

The wiring board 11 configured as described above
Include a front outer lead 25 and a back outer lead 35 as leads for ensuring electrical connection with the outside.
Are soldered to the front lands 20 and the back lands 30, respectively, and are electrically and mechanically connected to each other. In this connection state, the front outer lead 2
5 and each of the back outer leads 35 are arranged alternately. That is, the pitch Q between the adjacent front outer lead 25 and back outer lead 35 is half the pitch P set for the front outer lead 25 group and the back outer lead 35 group.

An insert portion 26 is bent at a right angle and integrally protrudes from the upper end of the front outer lead 25. The insert portion 26 is inserted into a through hole 23 formed in the front land 20. There is. A male taper portion 27 is tapered at the tip of the insertion portion 26. When the insertion portion 26 is inserted into the through hole 23, the male taper portion 27 guides the insertion to ensure the insertion work. And it's easy to do.

The width W of the diagonal line in the cross section of the insertion portion 26, that is, the maximum width W, is formed to be the same as or slightly larger than the inner diameter D of the through hole 23. Therefore, as shown in FIG.
When the insertion portion 26 is inserted into the through hole 23, the insertion portion 26 bites into the through hole conductor layer 24,
It is in a state of being mechanically fixed to the through hole 23.

Further, the length L of the insertion portion 26 is formed shorter than the depth H of the through hole 23. Therefore, as shown in FIG. 2D, when the insertion portion 26 is inserted into the through hole 23, the tip of the insertion portion 26 does not project to the back surface side of the wiring substrate 11, and the through hole 23
It is in a state that fits inside.

Similarly, at the upper end of the back outer lead 35, an insertion portion 36 is bent and integrally projected.
The insertion portion 36 is inserted into the through hole 33 formed in the back side land 30. A male taper portion 37 is also formed on the insertion portion 36. Further, the maximum width W of the insertion portion 36 is also formed to be equal to or larger than the inner diameter D of the through hole 33, and is in a state of biting into the through hole conductor layer 34.
Further, the length L of the insertion portion 36 is also formed to be shorter than the depth H of the through hole 33, and the tip of the insertion portion 36 has the tip thereof through the through hole 3.
It is in a state of being within 3.

A soldering portion 28 is formed in a contact surface region between the front side land 20 and the through hole conductor layer 24 and the front side outer lead 25. By the front side soldering portion 28, the front side outer lead 25 is in a state of being electrically and mechanically connected to the front side land 20 and the through hole conductor 24. Therefore, the front outer lead 25 is electrically connected to the front electric wiring 15 via the front land 20 and the through-hole conductor layer 24. As a result, the front outer lead 25 is attached to the wiring board 1.
The SOP / IC 17 mounted on the No. 1 can be electrically connected to the outside.

Similarly, a soldering portion 38 is formed in the contact surface region between the back side land 30 and the through hole conductor layer 34 and the back side outer lead 35. By the back side soldering portion 38, the back side outer lead 35 is in a state of being electrically and mechanically connected to the back side land 30 and the through hole conductor 34. Therefore, the back outer lead 35 is electrically connected to the back electrical wiring 16 via the back land 30 and the through hole conductor layer 34. As a result, the back outer lead 35 is attached to the wiring board 11
The SOP / IC 17 mounted on the vehicle can be electrically connected to the outside.

By the way, before being attached to the land, the outer lead group is configured as a lead frame shown in FIG. The lead frame 40 includes a tie bar 41 formed in an elongated rectangular plate shape. On one long side of the tie bar 41, a plurality of outer lead materials 42 to be outer leads are arranged at an equal pitch,
Further, they are integrally projected so as to be parallel to each other and orthogonal to the tie bar 41. The pitch P of the outer lead material group 42 is set to be equal to the pitch P of the outer lead group.

The tip of each outer lead material 42 is bent at a right angle, and the bent portion 43 forms the above-mentioned insertion portion. Bent portion 43
A male taper portion 27 (37) is formed at the tip of the. Further, the maximum width W of the bent portion 43 is formed to be equal to or larger than the diameter D of the through hole, and the length L of the bent portion 43 is formed to be shorter than the depth H of the through hole.

When the outer leads are assembled to the wiring board, a pair of lead frames 40 having the above-described structure (corresponding to the front and back sides) and a bent portion 43 as shown in FIG. Each headed to
In addition, in a state in which the front and rear outer lead material groups 42 are arranged so as to be displaced by a pitch Q which is a half of the pitch P, the bent portions 43 of the front and rear outer lead materials 42 are arranged on the through holes 23 of the front side land 20 in the wiring board 1 and on the back side. The land 30 and the through hole 33 are respectively inserted. At the time of this insertion, the male taper portions 27, 3 are attached to the tip of the bent portion 42.
Since 7 is formed, the insertion into the through holes 23 and 33 can be performed accurately and easily.

As described above, since the bent portion 43 inserted into the through hole bites into the through hole conductor layers 24 and 34, it is securely fixed. Therefore, the lead frames 40 on both sides are fixedly assembled to the front and back surfaces of the wiring board 11, respectively. The outer lead materials 42, 42 are arranged alternately on the front and back sides.

The wiring board 11 in which the lead frames 40, 40 are assembled on the front and back surfaces in this way is soldered by being dipped in a molten solder material after flux is applied to the soldering area. .. At this time, the pitch P of the outer leads 25 and 35 arranged on the front surface and the back surface is
Since it is twice the pitch Q between the rear outer lead 35 and the back outer lead 35, it is between the soldering portions 28 of the front outer lead and the soldering portion 3 of the rear outer lead 3 which are adjacent to each other.
No solder bridge is formed between 8 and 38.

Further, since the insertion portion 26 which is bent and inserted into the tip portion of the outer lead is accommodated in the through holes 23 and 33, the solder heap portion is not formed on the opposite side of the through holes 23 and 33. Therefore, the pitch P of the front outer lead group 25 and the back outer lead group 35 maintains the same dimension without being affected by the soldered portion of the outer lead on the opposite side. Therefore, the front outer lead 25 and the back outer lead 3
Even if 5 and 5 are arranged alternately with a half pitch Q, a solder bridge is not formed.

Thereafter, the lead frame 40 is attached to the tie bar 4
1 is cut off, and the outer leads 25 and 35 are separated from each other. As a result, the hybrid integrated circuit device 10 having the above configuration is manufactured.

According to the above embodiment, the following effects can be obtained. Since the terminal lands are arranged alternately on the front surface and the back surface of the wiring board, the pitch dimension of the terminal land group on the front surface side and the pitch dimension of the terminal land group on the back surface side are all terminal land groups on the front surface side. 2 compared to the case of arranging in a row
Doubled. Therefore, as the pitch gets wider,
It is possible to prevent generation of solder bridges between adjacent terminal lands.

Since the outer lead is fixed by inserting the bent insertion portion into the concave portion of the front side terminal land and the concave portion of the back side terminal land respectively, the fixing portion of the outer lead is exposed to the opposite side like the clamp portion. There is nothing to do. Therefore, unlike the case where the clamp portion is formed on the outer lead, the phenomenon that the pitch dimension of the outer lead on the front side is substantially halved by the outer lead on the back side does not occur.

Moreover, when the outer lead is soldered to the terminal land, the outer lead is prevented from floating by inserting the bent insertion portion into the recess, so that the outer lead is accurately positioned on the terminal land. It will be soldered in the state.

The insertion portions 26, 36 are not limited to being formed by the bent portion 43 that is bent at the tip of the outer lead material 42. For example, as shown in FIG. You may comprise by the convex part 44 protrudingly provided. The convex portion 44 may be formed by welding a chip of solder material or the like, or the outer lead material 43 may be bulging-molded into an embossed shape. Furthermore, the convex portion 44 is not limited to a conductive material, and may be formed of an insulating material such as resin.

FIG. 6 is a partially omitted front view showing a hybrid integrated circuit device according to another embodiment of the present invention.

The second embodiment differs from the first embodiment in that
The lands 20, 30 and the through holes 23, 33 are formed on the front surface and the back surface of the wiring board 11 so as to be the same.
The lands 30 or 20 are alternately arranged on the front surface and the back surface by one pitch, and the lands 30 or 20 are alternately covered with the coating layer 39 made of a solder resist or the like.
8 or 28 is not formed.

Also in the second embodiment, since the pitch P of the front outer lead group 25 and the rear outer lead group 35 remains wide, no solder bridge is formed.

Although the invention made by the present inventor has been specifically described based on the embodiments, the invention is not limited to the embodiments and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, the recess formed in the land is not limited to the through hole, but may be formed in the shape of a hole that does not penetrate. Also, the through-hole conductor layer may be omitted.

The insertion portion is not limited to be provided at the tip of the lead, but may be provided at the middle of the lead. Further, not only the lead is partially bent and molded, but the lead may be partially bulged and embossed to form the insertion portion. Moreover, the insertion portion may not have conductivity. In short, the insertion portion may be configured to be capable of temporarily fixing the lead to the land by being inserted into the concave portion during the soldering process.

The soldering portion is not limited to be formed by dipping solder treatment, but may be formed by flow solder treatment, reflow solder treatment, or the like.

In the above description, the case where the invention made by the present inventor is mainly applied to the manufacturing technology of the hybrid integrated circuit device used for the module of the computer which is the background field of application has been described, but the invention is limited thereto. However, the present invention can be applied to a hybrid integrated circuit device used in another electronic device or electronic device.

[0051]

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

Since the terminal lands are alternately arranged on the front surface and the back surface of the wiring board, the pitch dimension of the terminal land group on the front surface side and the pitch dimension of the terminal land group on the back surface side are all on the front surface side. It is twice as wide as when the terminal lands are arranged in a line. Therefore, the solder bridge between adjacent terminal lands can be prevented from occurring due to the increased pitch.

The leads are fixed by inserting the projecting insertion portions into the concave portions of the front side terminal lands and the concave portions of the back side terminal lands respectively. Therefore, like the clamp portions, the fixing portions of the outer leads are arranged on the opposite side. Never exposed. Therefore, unlike the case where the clamp portion is formed on the lead, the phenomenon that the pitch dimension of the front side lead is substantially halved by the back side lead does not occur.

Moreover, when the lead is soldered to the terminal land, the lead is prevented from floating by inserting the projecting insertion portion into the recess.
The leads will be soldered while being correctly positioned on the terminal lands.

[Brief description of drawings]

FIG. 1 is a front view showing a hybrid integrated circuit device according to an embodiment of the present invention.

2 is a sectional view taken along the line aa, a sectional view taken along the line bb of FIG. 1, a partially cutaway enlarged partial front view of the c section, and a partially omitted side sectional view thereof.

FIG. 3 is a front view showing a wiring board used in a method for manufacturing a hybrid integrated circuit device.

FIG. 4 is a partially omitted perspective view showing a lead frame.

FIG. 5 is a partially omitted perspective view showing a modified example of the lead frame.

FIG. 6 is a partially omitted front view showing a hybrid integrated circuit device according to another embodiment of the present invention.

FIG. 7 is a front view and an enlarged partial side sectional view showing a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Wiring board, 2 ... Terminal land, 3 ... Outer lead (lead), 4 ... Clamp, 5 ... Soldering part, 10 ... Hybrid integrated circuit device, 11 ... Wiring board, 12 ... Insulating board, 13
… Glass / epoxy board, 14… Ceramic board, 15, 1
6 ... Electric wiring, 17 ... SOP / IC, 20 ... Front side land (terminal land), 21 ... Rectangular part, 22 ... Circular part, 23 ...
Through hole, 24 ... Through hole conductor layer, 25 ... Front outer lead (lead), 26 ... Insertion part, 27 ... Male taper part, 28 ... Soldering part, 30 ... Back side land (terminal land), 33 ... Through hole, 34 ... through-hole conductor layer, 35 ... back outer lead (lead), 39 ... coating layer, 40 ... lead frame, 41 ... tie bar, 42 ... outer lead material, 43 ... bent portion, 44 ... convex portion.

Claims (3)

[Claims] 1. A plurality of terminal lands are arranged in a line along one edge of a wiring board so as to be spaced apart from each other along the edge, and each of the terminal lands is formed in a linear shape. In the hybrid integrated circuit device in which the formed leads are arranged so as to intersect the end side and soldered, the terminal land group is provided on the front surface and the back surface of the wiring board,
Adjacent ones are arranged so as to alternate between the front surface and the back surface, and a plurality of concave portions are arranged on the front surface and the back surface of the wiring board, respectively, on the front surface side terminal land and the back surface side terminal land. A hybrid integrated circuit device, wherein each of the leads is provided with an insertion part protruding from a part of the lead, and the insertion part is inserted into each of the recesses. 2. A conductor layer is attached to an inner peripheral surface of each of the recesses, and each conductor layer is soldered to an insertion portion of each of the leads.
The hybrid integrated circuit device according to. 3. The hybrid integrated circuit device according to claim 1, wherein the insertion portion of the lead has a maximum outer diameter slightly larger than an inner diameter of the recess.