JPH08191111A - Electronic part package - Google Patents

Abstract

PURPOSE: To obtain high reliable junction capable of making the rapid increase in pins more than conventional packages using both bumps and leads feasible as well as avoiding the change in the shape of bump electrodes for obviating defective connection. CONSTITUTION: Multiple bumps 2 are arranged and formed in a grid array shape on the rear surface of a package wherein an electronic component including active elements and passive elements and a molding resin are integrally molded while leads 3 are provided on the sides of four corner parts. Besides, electrodes a, b corresponding to the bumps 2 and leads 3 are arranged on a circuit substrate K. Finally, the shapes of the leads 3 are adjusted for setting up the optimum positions and heights to be fixed to the circuit substrate K.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component package structure for mounting a semiconductor element or electronic component.

[0002]

2. Description of the Related Art Conventional electronic component packages are broadly classified into those of the type in which they are connected to the substrate electrodes on the circuit board on which they are mounted via leads and those of the type in which they are connected via bumps. Among them, the lead type package is further classified into a lead insertion type and a surface mounting type. The surface mounting method is further classified into a gull wing (G), a J bend (J), an I lead (I), etc. depending on the shape of the lead.

FIGS. 4 and 5 show an external view or a sectional side view of a typical shape according to the above classification. FIG. 4A is an external view of the bump type package (BGA or the like) viewed from the back side, and a large number of hemispherical portions are bumps. (B) is the external shape of the lead-type package. Depending on the lead type, DIP (insertion lead), SOP (G), QFP
Abbreviated symbols of (G) and SOJ (J) PLC (J) C are given. Also, FIG. 5A is a lead insertion method, and FIG.
Is a surface mount type. Further, (b ') shows the type of lead shape.

An example of the above-mentioned electronic component package of the bump type connection type is disclosed in JP-A-2-37753. The package according to this publication has bump terminals as input / output terminals arranged in a grid array on the back surface of a substrate for fixing active elements (IC) and passive elements (resistors, capacitors, etc.) integrated in the package. ing.

Mold pins projecting to the back side of the substrate through holes provided at predetermined positions at the four corners of the substrate are integrally formed with a mold resin portion which is integrally covered on the above-mentioned element component, and the mold pins are formed in this package. It is provided as a guide member for indicating the mounting position and direction on the printed circuit board on which the electronic component is to be mounted. Therefore, when the mold pin is inserted into the hole of the printed circuit board, the bump terminal comes into contact with the electrode on the other printed circuit board for connection.

On the other hand, as an example of the lead type package, the one described in Japanese Patent Application Laid-Open No. 3-231448 is known. In the package described in this publication, a large number of joining pins are vertically projected from the back surface of the package integrally molded of resin, and only the four corners of the package are leads protruding laterally in an L shape, and a circuit board on which this package is mounted is mounted. The solder bumps are arranged in a grid array corresponding to the bonding pins, and pads are provided on the circuit board corresponding to the protruding leads.

In the package of this example, if the projecting leads are joined to the pads of the circuit board, the respective joining pins are aligned with the solder bumps at the same time, and electrical joining is possible.

[0008]

By the way, in the above-mentioned lead type package, the leads are generally formed on the side surface in many cases, it is difficult to cope with the increase in the number of pins, and the bottom surface of the package is not effectively utilized. In the above-mentioned second publication,
In order to improve this point, the leads are projected to the lower surface of the package. However, when trying to increase the number of pins by providing a large number of leads, it is difficult to accurately match the position of each pin and the bump on the circuit board. Is.

[0009] As a general example, as in the example of the above publication, the leads are arranged in an array on the bottom surface instead of the bumps, and the leads are abutted against the substrate instead of the insertion type and the surface mounting type package is used. There are cases in which leads are provided to prevent misalignment, but in this case bumps are generally easier to form and cost effective when forming leads in array form and bumps in array form. It is also cheap and it is easy to narrow the pitch.

On the other hand, the bump type package can easily cope with the increase in the number of pins, but since only the bump is generally formed on the bottom surface, it is difficult to prevent the displacement when connecting the bump and the substrate electrode. When the position shift occurs, it is difficult to repair the package structure and visually inspect the appearance, and it is difficult to judge the quality based on the size of the shift.

For example, as shown in FIG. 6, when the electrode portion of the bump 2 is fused at the time of mounting the package, (a) shows a normal bump fusion shape after fusion, but it is externally added later. When the bump 2 has a deformed shape as shown in (b) and (c) due to thermal or mechanical stress, the stress is likely to concentrate at a specific location, and the peripheral electrode portion a or the bump 2
There may be problems such as cracks and disconnections.
Since this is fixed to the circuit board K only by the bumps 2,
This is because when the bumps themselves melt, the above-mentioned deformation occurs.

Further, the amount of clearance between the bottom surface of the package 1 and the circuit board K cannot be controlled, and the shape of the bump 2 after fusion is left to the user. Therefore, depending on the shape of the bumps, excessive stress may remain or newly occur around the electrodes a of the package 1 or the circuit board K or on the bumps 2 themselves, which may lead to defects such as cracks and disconnections.

The package of the first publication described above attempts to solve the various problems described above, but the bondability between the bump and the electrode on the circuit board is still insufficient. The mold pin formed integrally with the mold resin is
Positioning is performed by inserting it into a hole provided in the circuit board, but the position of the mold pin is changed due to the clearance with the hole diameter, and if the mold pin itself is not correctly provided, the bump on the bottom surface of the package and the substrate electrode The position of is shifted. Also, since the mold pin is made of synthetic resin,
Since there is no electrical continuity and it cannot be used as an input / output terminal, there is a lot of space loss.

In consideration of various problems of the conventional electronic component package described above, the present invention makes it possible to dramatically increase the number of pins by using both bumps and leads as compared with the conventional package and to change the shape of the bump electrode portion. An object of the present invention is to provide an electronic component package capable of highly reliable bonding in which connection failure is prevented by preventing such occurrence.

[0015]

As a means for solving the above problems, the present invention is for integrally forming an electronic component including an active element and a passive element with a molding resin, and connecting it to an electrode of a circuit board on the bottom surface. The electronic component package is provided with bumps and leads for fixed support and signal input / output provided on the bottom surface, the side surface, or both surfaces thereof.

In the above-mentioned solution means, it is possible to adopt a surface mounting type in which the lead is joined to the circuit base surface. Alternatively, it may be of an insertion mounting type in which the lead is inserted through the circuit board. Further, the leads may be a combination of surface mount types.

[0017]

According to the first and second inventions having the above-mentioned structure, a plurality of bumps are provided on the bottom surface of the package, and leads are provided on the bottom surface, the side surface, or both surfaces thereof, so that the number of pins is dramatically increased as compared with the conventional package. Is provided to increase the number of pins and to prevent defective electrical connection, thereby enabling highly reliable bonding.

Based on the bump electrode, the lead is also used,
The shape can be appropriately deformed or adjusted by the lead to position it,
The height can be set optimally, and signals can be input and output from both leads and bumps.

Compared to the conventional bump type package, by setting the height and shape of the leads to predetermined values, the clearance amount between the package bottom surface and the substrate is physically fixed, and when mounting the package, the bump electrode portion The shape of the bumps does not change during fusion, or even after the fusion, even when subjected to external thermal or mechanical stress, it is possible to prevent floating, that is, electrical open defects, etc. A high bond can be obtained.

In the case of the lead insertion type as in the third and fourth inventions, by inserting the leads into the substrate, the position can be accurately fixed when the package is mounted on the substrate or at the time of fusion, and further the fusion is performed. There is also an effect that the position does not shift afterward.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an external perspective view of the electronic component package of the first embodiment. The electronic component package 1 includes an active element (IC chip) and a passive element (resistor, resistor,
(Capacitor etc.) and a molding resin is integrally molded thereon.

On the back surface of the package 1, a large number of bumps 2 are arranged in a grid array at appropriate intervals. Surface-mounted leads 3 are provided on the side surfaces of the package 1 near the four corners, respectively, as shown in FIG. This surface mounting has a so-called gull wing type lead shape.

In order to electrically connect the bumps 2 and the leads 3 when the package 1 having the above-described structure is mounted on the circuit board K, electrodes are arranged on the circuit board K in an arrangement corresponding to the bumps 2 and the leads 3. It is assumed that a and b are provided. By soldering the leads 3 to the electrodes b by soldering, the bumps 2 and the electrodes a and the leads 3 and the electrodes b are electrically conducted, and are supported and fixed to the circuit board K.

Since the gull wing type lead 3 is formed by bending the lead 3 into a substantially L shape, the leg length is adjusted in advance before being fixed by the solder joint c, so that The gap with the surface of the circuit board K can be set to a predetermined distance. If the grid array arrangement intervals of the bumps 2 and the corresponding electrodes a are separately formed in advance, the connection between the bumps 2 and the electrodes a can be surely secured even if the lead 3 is accurately set.

FIG. 2 shows a surface mount type similar to the lead 3 of the above embodiment, but shows another partial modification in which the shape of the lead is different. (A) is an example in which the lead 3'is formed on the bottom surface of the package, and (b) is an example in which a J-bend type is used as the lead 3 ". Others are the same as those in the above-described embodiment, and the same functional members are included. The same reference numerals are given and the description is omitted.

FIG. 3 shows an example in which the lead is of the insertion mounting type. (A) is an example in which the lead 3a is formed on the side surface of the package, (b) is an example in which the lead 3b is formed on the bottom surface of the package, and (c) is an example in which the lead 3 of the embodiment of FIG. 1 is combined with the example in (b). Is.

As in the case of the lead insertion mounting type of the conventional example, the lead 3 is inserted in the through hole provided in the circuit board K.
Insert either a or 3b and adjust the attachment position and height to fix. As a result, the bump 2 is accurately connected to the electrode a of the circuit board K.

[0028]

As described above in detail, in the first invention of this application, the bumps are provided on the bottom surface of the package and the leads are provided on the bottom surface, the side surfaces, or both surfaces thereof, so that it is dramatically more advanced than the conventional package. It becomes possible to easily increase the number of pins, and by adjusting the attachment of the leads, it is possible to maintain the clearance between the substrates and prevent the deformation of the bumps, thereby obtaining a highly reliable bump connection portion.

As in the second and third inventions, the method of mounting the leads may be either surface mounting type or insertion mounting type, and the clearance amount between the substrate and the package bottom surface can be controlled and fixed by the shape of the leads. . In particular, if the lead is an insertion type, it prevents misalignment when mounting the package,
Not only can reliability be improved, but repair and visual inspection can be simplified.

When the leads are mounted by both the surface mounting method and the insertion mounting method as in the fourth aspect of the invention, the reliability of the bondability is further enhanced.

[Brief description of drawings]

FIG. 1 is an external perspective view of an electronic component package of a first embodiment and a side view including a partial cross section.

FIG. 2 is a side view including a partial cross section showing a partially modified example of the electronic component package of the above.

FIG. 3 is a side view including a partial cross section of an electronic component package according to a second embodiment.

FIG. 4 is a perspective view of a bump-type and lead-type package according to the related art.

FIG. 5 is an explanatory diagram of classification formation of a lead-type package of a conventional example.

FIG. 6 is an explanatory view of bump welding bonding and its deformed state.

[Explanation of symbols]

 1 Package 2 Bumps 3, 3 ', 3 "Leads a, b Electrodes K Circuit board

Claims (4)

[Claims] 1. An electronic component including an active element and a passive element is integrally molded with a molding resin, a bump for connecting to an electrode of a circuit board is provided on the bottom surface, and leads for fixed support and signal input / output are provided on the bottom surface. Alternatively, an electronic component package provided on the side surface or both surfaces thereof. 2. The electronic component package according to claim 1, wherein the lead is of a surface mount type in which the lead is joined to the surface of the circuit board. 3. The electronic component package according to claim 1, wherein the lead is of an insertion mounting type in which the lead is inserted through a circuit board. 4. The electronic component package according to claim 3, wherein the leads are a combination of surface mount type leads.