JP2020198411A - High-density packaging module - Google Patents

Abstract

To improve mounting location accuracy by fixing an electronic component to a print circuit board with sufficient mechanical intensity, and inhibiting positional deviation at the time of solder reflow.SOLUTION: In a high-density packaging module including a print circuit board having multiple rands, and an electronic component mounted on the print circuit board and having multiple connection terminals for connection with the multiple rands, the multiple rands include first and second notches elongating oppositely in a first direction, and third and fourth notches elongating oppositely in a second direction orthogonal to the first direction, and solder fillets are formed from each lateral face of multiple connection terminals of the electronic component across the surface of respective rands connected with the connection terminals.SELECTED DRAWING: Figure 1

Description

The present invention relates to a high-density mounting module, and more particularly to a module in which electronic components are surface-mounted at high density on a printed circuit board.

With the progress of miniaturization and weight reduction of electronic device modules, miniaturization of individual electronic components such as semiconductor elements and electronic components to be mounted is being promoted. In this type of module, a technique of surface-mounting electronic components on a printed circuit board is adopted in order to realize high-density mounting commensurate with the miniaturization of the mounted components.

In this way, in a module that employs high-density surface mounting technology, individual electronic components are mounted on the printed circuit board by solder reflow technology to ensure the mechanical strength to fix the electronic components to the printed circuit board, and to ensure the electronic components. Reducing the electrical resistance between each connection terminal of the component and the conductive layer of the printed circuit board is compatible.

Japanese Unexamined Patent Publication No. 10-335795

In the above solder reflow technology, an appropriate amount of cream solder is adhered to the mounting land of the printed circuit board by a printing method, electronic components are aligned with the mounting land and mounted, and then heated once to melt the solder, and then The solder is solidified by cooling, and an electrical connection is obtained while fixing the electronic components on the printed circuit board.

In such surface mounting technology, when the solder is melted, the electronic components are in a floating state on the melted solder, so that the electronic components move on the solder until they are cooled and solidified. Then, it may be aligned and deviated from the original position where it was mounted. As a technique for suppressing such misalignment, for example, the technique described in Cited Document 1 has been proposed.

On the other hand, in order to secure the mechanical strength for fixing the electronic component to the printed circuit board, it is necessary to sufficiently form a solder fillet that surrounds the connection terminal of the electronic component on the mounting land. For this purpose, it is necessary to supply a sufficient volume of solder on the mounting land so as to surround the connection terminals of the electronic components, which makes it easier for the electronic components to move when the solder melts. Bring.

The present invention has been made in view of such a situation, and an object of the present invention is to sufficiently form a solder fillet that surrounds a connection terminal of an electronic component on a mounting land. The printed circuit board is fixed with sufficient mechanical strength, and at the time of solder reflow, electronic components are prevented from moving on the solder and deviating from the original position where they are aligned and mounted, which is good. It is to provide a high-density mounting module having mounting position accuracy.

The high-density mounting module according to the first aspect of the present invention includes a printed circuit board having a plurality of lands and an electronic component mounted on the printed circuit board and including a plurality of connection terminals connected to the plurality of lands. In the mounting module, the plurality of lands are formed in a first direction, a first notch extending in a direction opposite to each other, a second notch, and a second direction orthogonal to the first direction. Includes a third notch and a fourth notch extending in opposite directions, from each side of the plurality of connection terminals of the electronic component to the surface of each land to which the connection terminals are connected. An extending solder fillet is formed.

According to the second aspect of the present invention, in the first aspect, the plurality of lands have lands in which notches are not arranged.

According to the third aspect of the present invention, in the first aspect, the plurality of lands have lands in which only one notch is arranged.

According to the fourth aspect of the present invention, in the first aspect, the plurality of lands have at least four lands and four lands in which only one notch is arranged.

According to the fifth aspect of the present invention, in any one of the first aspect to the fourth aspect, each of the first notch and the second notch is arranged in separate lands. , The separate lands are separated from each other in the second direction.

According to the sixth aspect of the present invention, in any one of the first aspect to the fifth aspect, each of the third notch and the fourth notch is arranged in separate lands. , The separate lands are separated from each other in the first direction.

According to the seventh aspect of the present invention, in any one of the first aspect to the sixth aspect, the plurality of lands have a fifth notch extending in the first direction and a second aspect. It further includes a sixth notch extending in the direction of.

The high-density mounting module of the eighth aspect of the present invention comprises a plurality of lands and a solder resist having a plurality of openings covering the peripheral edges of the plurality of lands and contained within each region of the plurality of lands. A high-density mounting module comprising a printed circuit board having, and an electronic component including a plurality of connection terminals mounted on the printed circuit board and connected to a plurality of lands, the plurality of openings included in the plurality of lands. Face each other in the first direction and face each other in the second direction orthogonal to the first direction with the first protrusion and the second protrusion, each of which projects inward, and each of them is inside. Includes a third protrusion and a fourth protrusion that project in the direction, and extends from each side surface of the plurality of connection terminals of the electronic component to the surface of each land to which the connection terminals are connected. A solder fillet is formed.

According to the present invention, the electronic components are fixed to the printed circuit board with sufficient mechanical strength by sufficiently forming the solder fillets surrounding the connection terminals of the electronic components on the mounting land, and the electronic components are fixed. A high-density mounting module with good mounting position accuracy by preventing the position where the components are fixed from moving on the molten solder during solder reflow and shifting from the original position where they are aligned and mounted. Can be provided.

It is a top view of the 1st Embodiment of the high density mounting module of this invention. It is a top view of the modification of the 1st Embodiment of the high density mounting module of this invention. It is a top view of the further modification of the 1st Embodiment of the high density mounting module of this invention. It is sectional drawing of the line segment AA'in FIG. It is sectional drawing of the line segment BB'of FIG. It is sectional drawing of the line segment CC'of FIG. It is a top view of another modification of the 1st Embodiment of the high density mounting module of this invention. It is a top view of the 2nd Embodiment of the high density mounting module of this invention.

Hereinafter, various embodiments of the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 shows a module 101, which is a first embodiment of the high-density mounting module of the present invention. Module 101 includes a printed circuit board 105 having a first land 111, a second land 112, and a third land 113. The printed circuit board 105 has a first connection terminal 151, a second connection terminal 152, and a third connection terminal 151 connected to the corresponding first land 111, the second land 112, and the third land 113, respectively. The electronic component 150 including the connection terminal 153 of the above is mounted.

A first notch 121 extending in the first direction (X direction) is arranged in the first land 111, and the second land 112 is orthogonal to the first direction (X direction). A third notch 123 extending in the second direction (Y direction) is arranged. Further, the third land 113 has a second notch 122 extending in a direction facing the first notch 121 in the first direction (X direction) and a second notch 122 in the second direction (Y direction). A fourth notch 124 extending in a direction facing the notch 123 of the third is arranged.

In this first embodiment, when a force is generated during the solder reflow to move the electronic component floating in the molten solder in the negative direction in the first direction (X direction), the first notch 121 Suppresses the movement of the first connection terminal 151 of the electronic component. Then, when a force for moving in the positive direction is generated, the second notch 122 suppresses the movement of the third connection terminal 153 of the electronic component.

Similarly, when a force for moving in the negative direction in the second direction (Y direction) is generated, the third notch 123 suppresses the movement of the connection terminal 151 of the electronic component, and the force for moving in the positive direction. When the above occurs, the second notch 122 suppresses the movement of the third connection terminal 153 of the electronic component.

In this way, in order to prevent the electronic components floating in the molten solder from moving in parallel in the first direction (X direction) and in the second direction (Y direction), a plurality of lands Two notches extending in either direction, at least in the first direction (X direction), and a second direction (Y) orthogonal to the first direction (X direction). It is necessary to arrange two notches extending in opposite directions in the direction (direction).

However, the movement of the electronic component suspended in the molten solder is not limited to the parallel movement. For example, when a force for moving the electronic component in the negative direction in the first direction (X direction) is generated, the first cutting is performed. The notch 121 suppresses the movement of the first connection terminal 151 of the electronic component in the negative direction of the first direction (X direction), but the entire electronic component will rotate around the first notch 121. It is not possible to suppress the movement.

Similarly, with respect to the second notch 122, the third notch 123, and the fourth notch 124, similarly to the first notch 121, the electronic components in the directions in which the respective notches correspond. Although the translation of the connection terminals can be suppressed, the movement of the entire electronic component trying to rotate around each notch cannot be suppressed.

With respect to this movement to rotate, a plurality of notches can be combined to suppress misalignment. For example, with respect to the movement of trying to rotate clockwise around the first notch 121, the movement of the third connection terminal 153 is suppressed and prevented by the second notch 122 and the fourth notch 124. .. With respect to the movement to rotate counterclockwise, the movements of the first connection terminal 151 and the third connection terminal 153 are suppressed and prevented by the third notch 123 and the fourth notch 124. ..

Further, in the movement centered on the second notch 122, the clockwise rotation is caused by the movement of the first connection terminal 151 due to the first notch 121, and the counterclockwise rotation is caused by the third notch 123. And the fourth notch 124 suppresses the movement of each of the first connection terminal 151 and the third connection terminal 153.

In FIG. 1, the first land 111 in which the first notch 121 extending in the first direction (X direction) is arranged has a second notch 122 in a direction facing the first notch 121. The arranged third land 113 is separated from each other in a second direction (Y direction) orthogonal to the first direction (X direction) in which the first notch 121 and the second notch 122 extend. There is.

Further, in the second land 112 in which the third notch 123 extending in the second direction (Y direction) is arranged, the fourth notch 124 in the direction facing the third notch 123 is arranged. The third land 113 is separated from each other in the first direction (Y direction) orthogonal to the second direction (X direction) in which the third notch 123 and the fourth notch 124 extend.

Considering not only the direction in which the electronic components move in parallel but also the suppression of the positional deviation in the rotation direction, at least the two notches extending in the directions facing each other should be dispersedly arranged in the lands separated from each other. However, it is more preferable.

FIG. 2 shows a modified example of the module 101 of the first embodiment of the present invention. In this modification, in the module 101 shown in FIG. 1, the third notch 123 that was arranged in the second land 112 is arranged in the first land 111. The direction and direction in which the third notch 123 extends are the same as the direction and direction in which the third notch 123 shown in FIG. 1 extends. In this modification, no notch is not arranged in the second land 112.

Also in this modification, the first land 111 on which the third notch 123 extending in the second direction (X direction) is arranged is the fourth notch in the direction facing the third notch 123. The third land 113 on which the 124 is arranged is located in a first direction (Y direction) orthogonal to the second direction (X direction) in which the third notch 123 and the fourth notch 124 extend. It is separated.

FIG. 3 shows a further modification of the module 101 of the first embodiment of the present invention. In this further modification, in addition to the module 101 shown in FIG. 1, a fifth notch 125 extending in the first direction (X direction) of the second land 112 and a first of the third land 113. A sixth notch 126 extending in the direction of (X direction) and a seventh notch 127 extending in the second direction (Y direction) of the first land 111 are added.

The fifth notch 125 and the sixth notch 126 extend in the direction opposite to each other in the first direction (X direction), and the seventh notch 127 is the fourth notch 124 and the second notch 124. It extends in the direction opposite to each other in the direction (Y direction).

In this further modification, in the negative direction of the first direction (X direction), the movement of the first connection terminal 151 is suppressed by the first notch 121, and the third by the sixth notch 126. It also suppresses the movement of the connection terminal 153. Then, in the positive direction of the first direction (X direction), the second notch 122 and the fifth notch 125 suppress the movement of the third connection terminal 153 and the second connection terminal 152, respectively. To do.

In the negative direction of the second direction (Y direction), the third notch 123 and the seventh notch 127 suppress the movement of the second connection terminal 152 and the first connection terminal 151, respectively. In the positive direction of the second direction (Y direction), the movement of the electronic component is suppressed by the fourth notch 124, which is the same as the module 101 shown in FIG.

Further, in this further modification, the movement of the entire electronic component trying to move in the oblique direction is similarly suppressed. For example, the movement in the diagonal direction (positive / positive direction) in which the first direction (X direction) is positive and the second direction (Y direction) is also positive is the second notch 122 and the fourth notch 124. Suppresses and prevents the movement of the third connection terminal 153.

Similarly, for positive / negative movement, the third notch 123 and the fifth notch 125 suppress the movement of the second connection terminal 152, and for negative / positive movement, the fourth cut. The notch 124 and the sixth notch 126 suppress the movement of the third connection terminal 153, and the movement in the negative / negative direction is such that the first notch 121 and the seventh notch 127 are the first connection terminals 151. It is possible to suppress the movement of electronic parts and prevent the movement of electronic parts.

In this way, if the translation in the first direction (X direction) and the parallel movement in the second direction (Y direction) can be suppressed and the misalignment in the four diagonal directions can be suppressed, the electron can be electron centered at an arbitrary point. All movements of rotating parts can be suppressed. In this further modification, all of them have the effect of suppressing the misalignment equally with respect to the direction.

4, 5 and 6, respectively, are a cross-sectional view of the line segment AA'and the line segment BB'of the third land 113 described in FIG. 3, and the line segment of the second land 112, respectively. It is sectional drawing of the part of CC'. In FIGS. 4 and 5, a third land 113 is arranged on the printed circuit board 105, and a third connection terminal 153 of the electronic component 150 is soldered onto the third land 113.

Here, since the line segment AA'is a portion where the second notch 122 and the sixth notch 126 are arranged, the third land 113 is lateral from the end of the third connection terminal 153. The amount of protrusion in the direction is small. Further, since the solder at the time of melting can be held only on the third land 113 which is the conductive layer, the amount of the melted solder wrapping around the end of the third connection terminal 153 in the lateral direction is very small. Therefore, a thin solder layer 160 is formed on the surface of the third land 113 without forming a solder fillet.

On the other hand, the phenomenon that the electronic component 150 is displaced in the solder reflow process is caused by floating and moving on the molten solder. Therefore, if there is no wraparound of the molten solder in the lateral direction at the end of the third connection terminal 153, the third connection terminal 153 cannot move in the lateral direction, that is, in the A direction and the A'direction in FIG. Can not. Therefore, in the portion where the notch is arranged, the movement of the electronic component in the direction approaching the notch is suppressed during the solder reflow.

FIG. 5 is a cross-sectional view of the third land 113 in which the notch is not formed, and both ends of the third land 113 protrude greatly in the lateral direction from the third connection terminal 153. Therefore, the wraparound of the molten solder in the lateral direction of the end portion of the third connection terminal 153 is sufficient, and the solder fillet extends from both end side surfaces of the third connection terminal 153 to the surface of the third land 113. 165 is formed.

As described above, the solder fillet 165 is formed by sufficiently securing the lateral protrusion amount of the third land 113 from both ends of the third connection terminal 153, and the third connection terminals 153 and the third It is possible to secure the mechanical strength for fixing the land 113, that is, the mechanical strength for fixing the electronic component 150 to the printed circuit board 105.

FIG. 6 shows a cross-sectional view of a line segment CC ′ in which a second connection terminal 152 is arranged in a second land 112 in which a fifth notch 125 is arranged on one side. Similar to the third land 113, no solder fillet is formed in the vicinity of the fifth notch 125, and the portion without the notch extends from the side surface of the second connection terminal 152 to the second land 112. Sufficient solder fillets 165 present are formed.

As described above, the movement of the electronic component 150 at the time of solder reflow can be suppressed at the portion where the notch is arranged on the land. Further, even in the land on which the notch is arranged, a solder fillet that holds the electronic component with sufficient strength can be formed except in the vicinity of the notch.

As described above, according to the first embodiment of the present invention, the solder fillets surrounding the connection terminals of the electronic components are sufficiently formed on the mounting land, so that the electronic components can be used as a printed circuit board. It is good because it is fixed with a certain strength and the position where the electronic component is fixed is prevented from moving on the molten solder during the solder reflow and deviating from the original position where it is aligned and mounted. It is possible to provide a high-density mounting module having various mounting position accuracy.

FIG. 7 is a plan view showing another modification of the first embodiment. In this other modification, at least four lands 211, 212, 213, 214 are included, and the minimum required four notches 221, 222, 223, 224 are formed in the lands 211, 212, 213, 214. One is distributed to each. In the case of an electronic component having four or more connection terminals, it is more preferable that the notches are dispersedly arranged at positions separated from each other.

<Second embodiment>
FIG. 8 is a plan view showing a second embodiment of the high-density mounting module of the present invention. In this further modification, the solder structure of the first embodiment shown in FIG. 1 is realized by an overresist structure.

Module 101 includes a printed circuit board 105 having a first land 341, a second land 342, and a third land 343. On the printed circuit board 105, a first connection terminal 151, a second connection terminal 152, and a third are connected to the corresponding first land 341, the second land 342, and the third land 343, respectively. The electronic component 150 including the connection terminal 153 of the above is mounted.

The surface of the printed circuit board 105 is covered with a solder resist. The solder resist is provided with a first opening 311 that covers the peripheral edge of the first land 341 and is included in the area where the first land 341 is arranged, and the first opening 311 has a first opening 311. A first protrusion 321 that projects inward in one direction (X direction) is arranged. In addition, a second opening 312 that covers the peripheral edge of the second land 342 and is included in the area where the second land 342 is located is also arranged, and the second opening 312 is arranged in the first direction ( A third protrusion 323 that projects inward in a second direction (Y direction) that is orthogonal to the X direction) is arranged.

Further, the solder resist is provided with a third opening 313 that covers the peripheral edge of the third land 343 and is included in the area where the third land 343 is arranged, and the third opening 313 is provided with a third opening 313. , A second protrusion 322 that protrudes in the direction facing the first protrusion 321 in the first direction (X direction), and a direction facing the third protrusion 323 in the second direction (Y direction). A fourth protrusion 324 and a protrusion 324 are arranged.

In this second embodiment, the first land 341, the second land 342, and the third land exposed in the portions of the first opening 311 and the second opening 312, and the third opening 313 of the solder resist. Cream solder can be selectively printed on each surface of the land 343 to perform solder reflow. At this time, cream solder is not formed on the respective protrusions 321 to 324 protruding inward from the respective openings 31 to 313.

While the solder is melted in the reflow step, the solder melted on each of the lands 341 to 343 flows only in the openings of the solder resist, so that the planar shape of the solder after the reflow is 311 of each opening. It has the same planar shape as ~ 313. Therefore, in the second embodiment, it is possible to design the planar shape of the solder after reflow by making the shape of the opening of the solder resist desired.

Also in the second embodiment, the plane shape of the solder is the same as that of the first embodiment shown in FIG. 1, so that the movement of electronic components floating in the molten solder is restricted during the solder reflow. Can be done. For example, when a force for moving in the negative direction in the first direction (X direction) is generated, the first protrusion 321 suppresses the movement of the first connection terminal 151 of the electronic component. Then, when a force for moving in the positive direction is generated, the second protrusion 322 suppresses the movement of the third connection terminal 153 of the electronic component.

Further, when a force for moving in the negative direction in the second direction (Y direction) is generated, the third protrusion 323 suppresses the movement of the connection terminal 151 of the electronic component, and the force for moving in the positive direction is applied. When it occurs, the second protrusion 322 suppresses the movement of the third connection terminal 153 of the electronic component, which can be realized in the same manner as in the first embodiment shown in FIG.

Therefore, even in the overresist structure, by providing an inwardly projecting portion in the opening of the solder resist, by designing the planar shape of the solder, the same effect as in the case of arranging the land with the notch is obtained. Can play.

As described above, according to the second embodiment, the solder fillets that surround the connection terminals of the electronic components are sufficiently formed on the mounting land, so that the electronic components have sufficient mechanical strength on the printed circuit board. The position where the electronic components are fixed is prevented from moving on the molten solder during the solder reflow and deviating from the original position where the electronic components are aligned and mounted, which is a good mounting position. It is possible to provide a high-density mounting module having accuracy.

101 Module 105 Printed Circuit Board 111-113 1st to 3rd Lands 121-126 1st to 6th Notches 150 Electronic Components 151-153 1st to 3rd Connection Terminals 165 Solder Fillet 301 Module 305 Printed Circuit Board 311- 313 1st to 3rd openings 321-24 1st to 4th protrusions 341 to 343 1st to 3rd lands 3513 to 53 1st to 3rd connection terminals 350 Electronic components X 1st direction Y 2nd Direction

Claims (8)

A printed circuit board with multiple lands and
A high-density mounting module including electronic components mounted on the printed circuit board and including a plurality of connection terminals connected to the plurality of lands.
The plurality of lands face each other in a second direction orthogonal to the first direction and a first notch and a second notch extending in a direction facing each other in the first direction. Including a third notch and a fourth notch extending into
A high-density mounting module in which solder fillets are formed from each side surface of the plurality of connection terminals of the electronic component over the surface of each land to which the connection terminals are connected. The high-density mounting module according to claim 1, wherein the plurality of lands have lands in which notches are not arranged. The high-density mounting module according to claim 1, wherein the plurality of lands have lands in which only one notch is arranged. The high-density mounting module according to claim 1, wherein the plurality of lands have at least four lands and four lands in which only one notch is arranged. One of claims 1 to 4, wherein each of the first notch and the second notch is arranged in separate lands, and the separate lands are separated from each other in the second direction. High-density mounting module described in. One of claims 1 to 5, wherein each of the third notch and the fourth notch is arranged in separate lands, and the separate lands are separated from each other in the first direction. High-density mounting module described in. The invention according to any one of claims 1 to 6, wherein the plurality of lands further include a fifth notch extending in the first direction and a sixth notch extending in the second direction. High-density mounting module. A printed circuit board having a plurality of lands and a solder resist having a plurality of openings covering each peripheral portion of the plurality of lands and included in each region of the plurality of lands.
A high-density mounting module including electronic components mounted on the printed circuit board and including a plurality of connection terminals connected to the plurality of lands.
The plurality of openings included in the plurality of lands face each other in the first direction, and the first protrusion and the second protrusion, each of which projects inward, are orthogonal to the first direction. Includes a third and fourth protrusions that face each other in a second direction and project inward, respectively.
A high-density mounting module in which solder fillets are formed from each side surface of the plurality of connection terminals of the electronic component over the surface of each land to which the connection terminals are connected.

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