JP2005322844A - Circuit board and semiconductor device - Google Patents

Abstract

A breakage of a solder portion between a circuit board and a surface-mounted component can be avoided with an external pressure from above or below with a simple configuration.
A circuit board 2 for mounting a semiconductor surface-mounted component 3, wherein a plurality of slit holes 5 to 8 are formed in the vicinity of corners of the surface-mounted component 3 mounted on the circuit board 2. Even when the external pressure is applied to the corner portions 2A to 2D of the circuit board 2 where stress is likely to be concentrated, the circuit board 2 is placed in the slit holes 5 to 8 by the slit holes 5 to 8. Since the inner peripheral side and the outer peripheral side can be physically separated, even when the corner portions 2A to 2D of the circuit board 2 are bent, the peripheral portion in the vicinity of the corner portion of the surface mount component 3 on the circuit board 2 Can avoid deformation such as bending or warping, and thus, breakage of the solder portion between the surface mount component 3 and the circuit board 2 can be avoided.
[Selection] Figure 10

Description

  The present invention relates to a circuit board and a semiconductor device, and is suitably applied to a semiconductor device configured by mounting a surface mounting component such as a BGA (Ball Grid Array) on a circuit board.

  Conventionally, as shown in FIG. 16, the semiconductor device 100 is configured by mounting a surface mounting component 3 such as a BGA in a substantially central area of a circuit board 2. In such a semiconductor device 100, in recent years, the size of the surface-mounted component 3 has been increased, and the solder land on the circuit board 2 has been further reduced in diameter.

  As shown in FIG. 17A, when the surface mounting component 3 is mounted at a predetermined position on the mounting surface of the circuit board 2, the semiconductor device 100 solders the solder balls 4 of the surface mounting component 3 and the circuit board 2. Mounting is performed with an attached land (not shown) facing each other.

  As shown in FIG. 17B, in the semiconductor device 100, for example, when external pressures F1 and F2 are applied to the two corners on the diagonal line on the circuit board 2 from above, stress is concentrated at the corners. Therefore, even if the external pressures F1 and F2 are small, the corner portion of the circuit board 2 is bent, whereas the surface mounting component 3 is not bent in the same manner as the circuit board 2. The solder portion of the solder ball 4 connected between the component 3 and the circuit board 2 is broken.

  There are various types of breakage, such as a case where the solder portion itself is broken and a case where the soldered land of the circuit board 2 or the surface mounting component 3 is peeled off. In order to avoid such breakage, there is a method of using a resin sealing material such as an underfill resin which is a liquid resin between the surface mounting component 3 and the circuit board 2, but an assembly process for that purpose must be added. There is also a problem that must be done.

On the other hand, there is one in which a slit-like hole is formed in the printed wiring board in order to block conduction of heat from the heat generating electronic device to the printed wiring board (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 11-40901

  By the way, in the semiconductor device 100 having such a configuration, as shown in the printed wiring board of Patent Document 1, the point of forming slit-like holes corresponding to the four sides of the heat-generating electronic device having a rectangular shape is taken in, Even if the same slit-like hole is formed in the circuit board 2, when external pressures F1 and F2 are applied from the upper direction to the two corners on the diagonal line of the circuit board 2, the same is applied as shown in FIG. ) Although the corner portion of the circuit board 2 bends as shown in FIG. 3B, the surface mount component 3 is difficult to bend, so that the solder portion connected between the surface mount component 3 and the circuit board 2 is broken. was there.

  Further, as shown in FIGS. 18A, 18B, and 18C, the semiconductor device 100 is applied with external pressures F3 and F4 from the lower direction to the two corners on the diagonal line of the circuit board 2. The circuit board 2 is warped upward by the external pressures F3 and F4, and the solder part between the circuit board 2 and the surface mounting component 3 is crushed. As a result, when the external pressures F3 and F4 are no longer applied, the solder part is broken. There was a problem that.

  The present invention has been made in consideration of the above points, and is intended to propose a circuit board and a semiconductor device that can avoid breakage of a solder portion with respect to external pressure from above or below with a simple configuration. is there.

  In order to solve such a problem, in the present invention, a circuit board for mounting a semiconductor surface-mounted electronic component, which is formed in the vicinity of a corner of the surface-mounted electronic component mounted on the circuit board. By providing the slit hole, even when external pressure is applied to the corner portion of the circuit board where stress is likely to concentrate, the portion near the corner of the surface mount electronic component on the circuit board bends or warps due to the external pressure. Such deformation can be avoided by the plurality of slit holes, and breakage of the solder portion between the surface mount electronic component and the circuit board can be avoided.

  According to the present invention, there is also provided a semiconductor device including a semiconductor surface-mounted electronic component and a circuit board for mounting the surface-mounted electronic component, wherein the circuit board is mounted on the circuit board. By providing a plurality of slit holes formed in the vicinity of the corner of the electronic component, even when external pressure is applied to the corner of the circuit board where stress is likely to concentrate, surface mount electronics on the circuit board It is possible to avoid deformations such as a portion near the corner of the component being bent or warped by an external pressure by the plurality of slit holes, and to avoid breakage of the solder portion between the surface mount electronic component and the circuit board.

  According to the present invention, even when an external pressure is applied to a corner portion of a circuit board where stress is easily concentrated, a portion near the corner of the surface mount electronic component on the circuit board is bent or warped by the external pressure. Thus, it is possible to realize a circuit board and a semiconductor device capable of avoiding the deformation by the plurality of slit holes and avoiding breakage of the solder portion between the surface mount electronic component and the circuit board.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

(1) First Embodiment In FIG. 1, in which parts corresponding to those in FIG. 16 are given the same reference numerals, 1 denotes a semiconductor device according to the first embodiment of the present invention as a whole, and a rectangular circuit A rectangular surface-mounted component 3 is mounted almost at the center of the substrate 2, and is a substantially right-angled L-shape formed around the surface-mounted component 3 and covering each corner of the surface-mounted component 3. A plurality of slit holes 5 to 8 are provided.

  The slit holes 5 to 8 are through holes formed in the circuit board 2, and when the external pressure is applied to the corner portions 2 </ b> A to 2 </ b> D of the circuit board 2, the bending of the circuit board 2 is a surface. It is possible to avoid reaching the vicinity of the corner of the mounting component 3.

  As shown in FIGS. 2A and 2B, for example, in the semiconductor device 1, when the external pressures F1 and F2 are applied to the corner portions 2A and 2B of the circuit board 2 from above, Even when the external pressures F3 and F4 are applied to the portions 2A and 2B from below, the slits 6 and 8 are used to slit the circuit board 2 as shown in FIGS. 3 (A) and 3 (B). By physically separating the inner peripheral side and the outer peripheral side of the holes 6 and 8, the outer peripheral side portions of the slit holes 6 and 8 in the circuit board 2 are bent by the external pressures F1 and F2. The inner peripheral portions 2P and 2Q of the slit holes 6 and 8 are not bent without being affected by the external pressures F1 and F2 and the external pressures F3 and F4.

  In other words, the semiconductor device 1 has the surface of the circuit board 2 even when the external pressures F1 and F2 and the external pressures F3 and F4 are applied to the corner portions 2A and 2B of the circuit board 2 from above or below. Since the peripheral portions 2P and 2Q of the mounting component 3 can be kept substantially parallel to the surface mounting component 3, the solder portion between the circuit board 2 and the surface mounting component 3 is affected. In this way, breakage of the solder portion can be avoided.

  This is the same even when external pressures F1 and F2 and external pressures F3 and F4 from above or below are applied to the corner portions 2C and 2D of the circuit board 2.

  Thereby, the semiconductor device 1 is a case where the external pressures F1 and F2 and the external pressures F3 and F4 from the upper direction or the lower direction are applied to the corner portions 2A and 2B of the circuit board 2 where stress tends to concentrate. The peripheral portions 2P and 2Q of the surface mounting component 3 of the circuit board 2 located on the inner peripheral side of the slit holes 5 to 8 are bent by the slit holes 5 to 8 formed so as to cover the corners of the surface mounting component 3. It is possible to avoid deformation such as curling or warping, and thus it is possible to prevent the solder portion between the surface mount component 3 and the circuit board 2 from being broken.

(2) Second Embodiment In FIG. 4, in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, 10 denotes a semiconductor device according to a second embodiment of the present invention as a whole, and a rectangular circuit A rectangular surface-mounted component 3 is mounted at substantially the center of the substrate 2 and is orthogonal to the diagonal line around the surface-mounted component 3 and at a predetermined position on both diagonal lines for the circuit board 2 and the surface-mounted component 3. Slit holes 11 to 14 having a predetermined length are provided.

  Similarly to the slit holes 5 to 8 in the first embodiment, the slit holes 11 to 14 are through holes formed in the circuit board 2, and are formed in the corner portions 2 </ b> A to 2 </ b> D of the circuit board 2. On the other hand, when an external pressure is applied, the circuit board 2 can be prevented from being bent near the corners of the surface mount component 3.

  As shown in FIGS. 5A and 5B, in the semiconductor device 10, when the external pressures F1 and F2 are applied to the corner portions 2A and 2B of the circuit board 2 from above, Even when external pressures F3 and F4 are applied to 2A and 2B from below, as shown in FIGS. 6 (A) and 6 (B), the circuit board 2 is held by the slit holes 12 and 14 in the slit hole. Since the inner peripheral side and the outer peripheral side of 12 and 14 are physically separated, the outer peripheral side portions of the slit holes 12 and 14 in the circuit board 2 are bent by the external pressures F1 and F2 and the external pressures F3 and F4. However, the inner peripheral portions 2R and 2S of the slit holes 12 and 14 are not bent because they are not affected by the external pressures F1 and F2 and the external pressures F3 and F4.

  In other words, the semiconductor device 10 has the surface of the circuit board 2 even when the external pressures F1 and F2 and the external pressures F3 and F4 are applied to the corner portions 2A and 2B of the circuit board 2 from above or below. Since the peripheral portions 2R and 2S of the mounting component 3 can be kept substantially parallel to the surface mounting component 3, the solder portion between the circuit board 2 and the surface mounting component 3 is affected. In this way, breakage of the solder portion can be avoided.

  This is the same even when external pressures F1 and F2 and external pressures F3 and F4 from above or below are applied to the corner portions 2C and 2D of the circuit board 2.

  As a result, the semiconductor device 10 can receive the external pressures F1 and F2 and the external pressures F3 and F4 from above or below the corner portions 2A and 2B of the circuit board 2 where stress is likely to concentrate. In the vicinity of the corner portion of the surface mounting component 3, the circuit board 2 is provided at predetermined positions on both diagonal lines of the circuit board 2 and the surface mounting component 3 through slit holes 11 to 14 formed so as to be orthogonal to the diagonal line. The peripheral portions 2R and 2S of the surface mount component 3 can be prevented from being bent or warped. Thus, the solder portion between the surface mount component 3 and the circuit board 2 can be prevented from being broken.

  In the semiconductor device 10, the longer the slit holes 11 to 14 are, the more the external pressures F1 and F2 applied to the corner portions 2A to 2D of the circuit board 2 and the influence of the external pressures F3 and F4 on the surface mount component 3 are affected. Therefore, the length can be set to any length according to the magnitudes of the external pressures F1 and F2 and the external pressures F3 and F4.

(3) Third Embodiment In FIG. 7, in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, 20 denotes a semiconductor device as a whole according to the third embodiment of the present invention, and a rectangular circuit A plurality of slits each having an arc shape formed so that a rectangular surface-mounted component 3 is mounted substantially at the center of the substrate 2 and is formed around the surface-mounted component 3 and covering each corner of the surface-mounted component 3. Holes 21 to 24 are provided.

  Similar to the first and second embodiments, the slit holes 21 to 24 are through holes formed in the circuit board 2, and are formed in the corner portions 2 </ b> A to 2 </ b> D of the circuit board 2. On the other hand, when an external pressure is applied, the circuit board 2 can be prevented from being bent near the corners of the surface mount component 3.

  As shown in FIGS. 8A and 8B, for example, in the semiconductor device 20, the external pressures F1 and F2 are applied to the corner portions 2A and 2B of the circuit board 2 from above, or the corners of the circuit board 2 Even when external pressures F3 and F4 are applied to the portions 2A and 2B from below, as shown in FIGS. 9A and 9B, the circuit board 2 is slit by the slit holes 22 and 24. By physically separating the inner peripheral side and the outer peripheral side of the holes 22 and 24, the outer peripheral side portions of the slit holes 22 and 24 in the circuit board 2 are bent by the external pressures F1 and F2 and the external pressures F3 and F4. However, the inner peripheral portions 2T and 2U of the slit holes 22 and 24 are not bent because they are not affected by the external pressures F1 and F2 and the external pressures F3 and F4.

  That is, the semiconductor device 20 has a surface of the circuit board 2 even when the external pressures F1 and F2 and the external pressures F3 and F4 are applied to the corner portions 2A and 2B of the circuit board 2 from above or below. Since the peripheral portions 2T and 2U of the mounting component 3 can be kept substantially parallel to the surface mounting component 3, the solder portion between the circuit board 2 and the surface mounting component 3 is affected. In this way, breakage of the solder portion can be avoided.

  In particular, the semiconductor device 20 is slightly deviated from the corner portions 2A and 2B of the circuit board 2 by forming the slit holes 21 to 24 so as to cover the corners of the surface mount component 3 and in a curved shape. Even when the external pressures F1 and F2 and the external pressures F3 and F4 from the upward direction or the downward direction are applied to the location, the influence of the external pressures F1 and F2 and the external pressures F3 and F4 is applied to the slit holes 21 to 24. It is easy to escape to the outer peripheral side, and the influence on the solder portion between the circuit board 2 and the surface mounting component 3 can be made extremely small to avoid breakage.

  As a result, the semiconductor device 20 has the corners of the surface mount component 3 even when the external pressures F1 and F2 and the external pressures F3 and F4 are applied to the vicinity of the corner portions 2A and 2B of the circuit board 2 where stress tends to concentrate. The peripheral portions 2T and 2U of the surface mount component 3 on the circuit board 2 can be prevented from being bent or warped by the arc-shaped slit holes 21 to 24 formed so as to cover the portion, and thus the surface mount component 3 can be avoided. And it can prevent that the solder part between the circuit boards 2 fractures | ruptures.

(4) Fourth Embodiment In FIG. 10, in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, 30 denotes a semiconductor device as a whole according to the fourth embodiment of the present invention. Similarly to the semiconductor device 1 in the above embodiment, a rectangular surface-mounted component 3 is mounted almost at the center of the rectangular circuit board 2, and the corner of the surface-mounted component 3 is formed around the surface-mounted component 3. A plurality of slit holes 5 to 8 each having a substantially right-angled L shape formed so as to cover each other are provided.

  Further, the semiconductor device 30 is a straight line formed so as to be partially overlapped with the slit holes 5 to 8 around the plurality of slit holes 4 to 7 in parallel with the respective sides of the surface mount component 3 and the circuit board 2. A plurality of auxiliary slit holes 31 to 34 are provided.

  The slit holes 5 to 8 are through-holes formed in the circuit board 2, and when external pressure is applied to the corner portions 2 </ b> A to 2 </ b> D of the circuit board 2, the circuit board 2 bends by surface mounting. It is possible to avoid reaching near the corner of the part 3.

  On the other hand, the auxiliary slit holes 31 to 34 are also through holes formed with respect to the circuit board 2, and for example, external pressures F1 and F2 from above are applied to the vicinity 2V and 2W of the left and right side central portions of the circuit board 2, for example. When applied, or when external pressure (not shown) from below is applied, it is possible to avoid the bending of the left and right sides of the circuit board 2 from reaching the vicinity of the side surface of the surface mounting component 3. ing.

  As shown in FIG. 12A, when the external pressures F1 and F2 are applied to the corner portions 2A and 2B of the circuit board 2 from the upper direction, the semiconductor device 30 moves the circuit board 2 through the slit holes 6 and 8. By physically separating the inner and outer peripheral sides of the slit holes 6 and 8, as shown in FIG. 13 (A), the outer peripheral side portions of the slit holes 6 and 8 in the circuit board 2 are subjected to external pressure. Although it will bend by F1 and F2, it will not bend about the inner peripheral side part of the said slit holes 6 and 8, since it will not receive to the influence of external pressure F1 and F2.

  Further, as shown in FIG. 12B, the semiconductor device 30 has auxiliary slit holes 31 to 34 when the external pressures F1 and F2 from the upper direction are applied to the central portions 2V and 2W in the left and right sides of the circuit board 2. By physically separating the circuit board 2 into the inner peripheral side and the outer peripheral side of the auxiliary slit holes 31 to 34, as shown in FIG. As for the outer peripheral side portion, the left and right side portions are bent by the external pressures F1 and F2. However, the inner peripheral side portions of the left and right side central portions 2V and 2W are not affected by the external pressures F1 and F2. Does not flex.

  That is, the semiconductor device 30 receives external pressures F1 and F2 from the upper direction or the external pressure from the lower direction with respect to the corner portions 2A and 2B and the central portions 2V and 2W in the left and right sides of the circuit board 2. Even in such a case, since the peripheral portion of the surface mounting component 3 in the circuit board 2 can be kept substantially parallel to the surface mounting component 3, the solder portion between the circuit board 2 and the surface mounting component 3 can be maintained. In this way, the solder portion can be prevented from being broken.

  As described above, in the semiconductor device 30, the surface mount component 3 on the inner peripheral side of the slit holes 5 to 8 and the auxiliary slit holes 31 to 34 and the slit holes are formed by the slit holes 5 to 8 and the auxiliary slit holes 31 to 34. 5-8 and corner portions 2A to 2D of the circuit board 2 on the outer peripheral side of the auxiliary slit holes 31 to 34 and the left and right side central portion neighborhoods 2V and 2W are pseudo-physically but physically separated. As a result, even if the external pressures F1 and F2 are applied to any part of the circuit board 2 on the outer peripheral side of the slit holes 5 to 8 and the auxiliary slit holes 31 to 34, the surface mount component 3 is subjected to It has been made possible to avoid the influence of this.

  This is the same even when external pressure F1 and F2 from the upper direction are applied to the corner portions 2C and 2D of the circuit board 2 and when external pressure from the lower direction is applied. The same applies to the case where the external pressures F1 and F2 from the upper direction are applied to the central portions 2X and 2Y and the case where the external pressure from the lower direction is applied.

  As a result, the semiconductor device 30 can be applied to the corner portions 2A and 2B of the circuit board 2 where stress is likely to be concentrated, even when external pressures F1 and F2 are applied from above. Even when external pressures F1 and F2 from above are applied to the vicinity 2V and 2W, the peripheral portion of the surface mounting component 3 on the circuit board 2 by the slit holes 4 to 7 and the auxiliary slit holes 31 to 34 Therefore, deformation such as bending or warping can be avoided, and thus the solder portion between the surface mount component 3 and the circuit board 2 can be reliably prevented from breaking.

(5) Other Embodiments In the above-described fourth embodiment, the semiconductor device 30 (FIG. 10) is configured by providing auxiliary slit holes 31 to 34 around the slit holes 5 to 8. Although the present invention is not limited to this, the slit holes 11 to 14 shown in the second embodiment are shown in FIG. You may make it comprise the semiconductor device 40 by providing the auxiliary slit holes 31-34 around (FIG. 4).

  In the fourth embodiment, the case where the semiconductor device 30 (FIG. 10) is configured by providing the auxiliary slit holes 31 to 34 around the slit holes 5 to 8 has been described. The invention is not limited to this, and as shown in FIG. 14 in which the same reference numerals are assigned to the corresponding parts as in FIG. 10, there is an auxiliary around the slit holes 21 to 24 (FIG. 7) shown in the third embodiment. The semiconductor device 50 may be configured by providing the slit holes 31 to 34.

  Further, in the fourth embodiment described above, the case where the semiconductor device 30 (FIG. 10) is configured by providing the auxiliary slit holes 31 to 34 around the slit holes 5 to 8 has been described. The invention is not limited to this, and as shown in FIG. 15, by providing arc-shaped auxiliary slit holes 61 to 64 around the slit holes 21 to 24 (FIG. 7) shown in the third embodiment, the semiconductor device is provided. 60 may be configured.

  Further, in the first to fourth embodiments described above, the case where the surface mounting component 3 such as BGA is used as the surface mounting electronic component to be mounted on the circuit board 2 has been described. Not limited to this, various other surface mount components such as LGA (Land Grid Array), PGA (Pin Grid Array), and QFN (Quad Flat Non-Lead Package) may be used.

  The circuit board and the semiconductor device of the present invention can be applied to various other uses in which an external pressure is applied to a circuit board on which surface-mounted components are mounted, for example.

1 is a schematic diagram illustrating a configuration of a semiconductor device according to a first embodiment of the present invention. It is a basic diagram which shows a state when the external pressure from the up-down direction with respect to the corner part in 1st Embodiment is given. It is a basic diagram with which it uses for description of the fracture avoidance state with respect to the external pressure in 1st Embodiment. It is a basic diagram which shows the structure of the semiconductor device in the 2nd Embodiment of this invention. It is a basic diagram which shows a state when the external pressure from the up-down direction with respect to the corner part in 2nd Embodiment is given. It is a basic diagram with which it uses for description of the fracture avoidance state with respect to the external pressure in 2nd Embodiment. It is a basic diagram which shows the structure of the semiconductor device in the 3rd Embodiment of this invention. It is a basic diagram which shows a state when the external pressure from the up-down direction with respect to the corner part in 3rd Embodiment is given. It is a basic diagram with which it uses for description of the fracture avoidance state with respect to the external pressure in 3rd Embodiment. It is a basic diagram which shows the structure of the semiconductor device in the 4th Embodiment of this invention. It is a basic diagram which shows a state when the external pressure from the upper direction with respect to the corner part in 4th Embodiment and the center part vicinity of both right-and-left both sides is given. It is a basic diagram with which it uses for description of the fracture avoidance state with respect to the external pressure in 4th Embodiment. It is a basic diagram which shows the structure of the semiconductor device (1) in other embodiment. It is a basic diagram which shows the structure of the semiconductor device (2) in other embodiment. It is a basic diagram which shows the structure of the semiconductor device (3) in other embodiment. It is a basic diagram which shows the structure of the conventional circuit board. It is a basic diagram with which it uses for description of the fracture | rupture at the time of the external pressure from an upper direction. It is a basic diagram with which it uses for description of the fracture | rupture at the time of the external pressure from a downward direction.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 10, 20, 30, 40, 50, 60, 100 ... Semiconductor device, 2 ... Circuit board, 2A-2D ... Corner part, 2P, 2Q, 2R, 2S, 2T, 2U, 2V, 2W ... ... peripheral parts, 3 ... surface mount components, 4 ... solder balls, 5-7, 11-14, 21-24 ... slit holes, 31-34, 61-64 ... auxiliary slit holes.

Claims (6)

A circuit board for mounting a semiconductor surface mount electronic component,
A circuit board comprising a plurality of slit holes formed in the vicinity of corners of the surface-mounted electronic component mounted on the circuit board. The circuit board according to claim 1, wherein the plurality of slit holes are formed so as to surround corners of the surface-mount electronic component. The circuit board includes, in addition to the plurality of slit holes, a plurality of auxiliary slit holes provided around the surface-mounted electronic component other than the corners of the surface-mounted electronic component. The circuit board according to claim 1. A semiconductor device comprising a semiconductor surface mount electronic component and a circuit board for mounting the surface mount electronic component,
The circuit board is
A semiconductor device comprising a plurality of slit holes formed in the vicinity of a corner of the surface-mounted electronic component mounted on the circuit board. The semiconductor device according to claim 4, wherein the plurality of slit holes are formed so as to surround a corner portion of the surface-mount electronic component. The circuit board includes, in addition to the plurality of slit holes, a plurality of auxiliary slit holes provided around the surface-mounted electronic component other than the corners of the surface-mounted electronic component. The semiconductor device according to claim 4.

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