JP5761664B2 - Wiring board - Google Patents

Description

  The present invention relates to a wiring board for mounting a semiconductor integrated circuit element.

  Conventionally, a wiring board formed by a build-up method is known as a wiring board for mounting a semiconductor integrated circuit element. FIG. 3 is a schematic cross-sectional view showing an example of a conventional wiring board formed by a build-up method, and FIG. 4 is a schematic perspective view of a main part of the wiring board shown in FIG. In FIG. 3, hatching is omitted.

  As shown in FIG. 3, the conventional wiring board has an insulating substrate 30 in which a plurality of buildup insulating layers 22 are laminated on the upper and lower surfaces of the core substrate 21. A mounting portion 30a for mounting the semiconductor integrated circuit element S is formed at the center of the upper surface of the insulating substrate 30, and the lower surface of the insulating substrate 30 serves as a connection surface for connection to an external electric circuit substrate. Yes.

  A core conductor layer 24 made of copper foil or a copper plating layer is deposited on the upper and lower surfaces of the core substrate 21. The core substrate 21 is formed with a plurality of through-hole conductors 25 penetrating from the upper surface to the lower surface.

  A build-up conductor layer 23 made of a copper plating layer is deposited on the surface of each build-up insulating layer 22. Furthermore, a plurality of via conductors 26 penetrating each insulating layer 22 are formed. The buildup conductor layer 23 is electrically connected to the through-hole conductor 25 while the upper and lower layers are connected to each other via the via conductor 26. Further, a part of the buildup conductor layer 23 deposited on the outermost buildup insulating layer 22 on the upper surface side is electrically connected to the electrode terminal T of the semiconductor integrated circuit element S in the mounting portion 30a. The circular semiconductor element connection pads 27 are formed, and these semiconductor element connection pads 27 are formed in a lattice pattern corresponding to the electrode terminals T of the semiconductor integrated circuit element S. Further, a part of the lower surface side deposited on the outermost buildup insulating layer 22 is a circular external connection pad 28 that is electrically connected to the wiring conductor of the external electric circuit board. A plurality of lines 28 are arranged in a lattice pattern.

  Further, a solder resist layer 29 that exposes the semiconductor element connection pads 27 and the external connection pads 28 is deposited on the outermost buildup insulating layer 22 and the buildup conductor layer 23 thereon. The electrode terminal T of the semiconductor integrated circuit element S is electrically connected to the exposed portion of the semiconductor element connection pad 27, and the wiring conductor of the external electric circuit board (not shown) is connected to the exposed portion of the external connection pad 28 via the solder ball. Are electrically connected.

  By the way, the semiconductor element connection pad 27 and the external connection pad 28 are provided for supplying a ground potential to the semiconductor element S, for supplying a power supply potential to the semiconductor element S, and between the semiconductor element S and the outside. For transmitting and receiving signals between them, and they are electrically connected to each other via corresponding through-hole conductors 25 and via conductors 26.

  In order to stably operate the semiconductor element S, it is important to stably give a sufficient ground potential and power supply potential to the semiconductor element S. For this purpose, when a current flows transiently from the grounding / power supply external connection pad 28 to the grounding / power supply semiconductor element connection pad 27, the potential drop between them is reduced. It is necessary to design to.

  Therefore, for example, by connecting a plurality of via conductors 26 to one external connection pad 28 for grounding or power supply and the through hole conductor 25 connected thereto, the connection between the external connection pad 28 and the through hole conductor 25 is achieved. A method of providing a via connection path for connecting a plurality of each at a plurality of locations is employed. In this case, since the external connection pad 28 and the through-hole conductor 25 connected to the external connection pad 28 are connected by a plurality of via connection paths, when a transient current flows between them, the potential between them is reduced. It can be kept small.

  Here, FIG. 4 is a perspective view of an essential part of the conventional example in which two via connection paths are provided to connect one grounding or power supply external connection pad 28 and the through-hole conductor 25 connected thereto. It shows with. In FIG. 4, only a part necessary for facilitating understanding of the via connection path is shown, and a part is shown by a broken line. In the conventional example shown in FIG. 4, the grounding through-hole conductor 25G, the grounding external connection pad 28G connected thereto, the power supply through-hole conductor 25P, and the power supply external connection pad 28P connected thereto are It is arranged adjacent to each other.

  The grounding through-hole conductor 25G is electrically connected to the grounding semiconductor element connection pad 27G through one via connection path 26Ga including the upper surface side via 26a, the upper surface side via land 23La, and the upper surface side through hole land 24La. Connected. Further, the power supply through-hole conductor 25P is electrically connected to the power supply semiconductor element connection pad 27P through one via connection path 26Pa including the via 26a, the via land 23La, and the through-hole land 24La on the upper surface side. ing. The via land 23La is formed from the buildup conductor layer 23 on the upper surface side, and the through-hole land 24La is formed from the core conductor layer 24 on the upper surface side.

  On the other hand, the grounding external connection pad 28G is positioned below the grounding through-hole conductor 25G, and includes two via connection paths including the lower surface side via 26b, the lower surface side via land 23Lb, and the lower surface side through hole land 24Lb. It is electrically connected to the grounding through-hole conductor 25G via 26Gb. The power supply external connection pad 28P is positioned below the power supply through-hole conductor 25P, and includes two via connection paths including the lower surface via 26b, the lower surface via land 23Lb, and the lower surface through hole land 24Lb. It is electrically connected to the through-hole conductor 25P for power supply through 26Pb. The via land 23Lb is formed from the build-up conductor layer 23 on the lower surface side, and the through-hole land 24Lb is formed from the core conductor layer 24 on the lower surface side.

  In this conventional wiring board, the two via connection paths 26Gb and 26Pb that connect one grounding or power supply external connection pads 28G and 28P and the through-hole conductors 25G and 25P connected thereto are respectively through-holes. The conductors 25G and 25P are provided so as to face each other at a position of 180 °, and between these two external connection pads 28G and 28P and the through-hole conductors 25G and 25P, these two via connection paths 26Gb, 26Pb was arranged in parallel with each other.

  In this way, by connecting one grounding / power supply external connection pads 28G, 28P and the through-hole conductors 25G, 25P connected thereto with two via connection paths 26Gb, 26Pb, respectively, A decrease in potential generated between the power supply external connection pads 28G and 28P and the through-hole conductors 25G and 25P connected thereto can be suppressed to some extent. In general, for example, as the number of via connection paths 26Gb and 26Pb that connect one grounding or power supply external connection pads 28G and 28P and the through-hole conductors 25G and 25P connected thereto increases, The decrease in potential during that time can be further reduced. However, as the number of via connection paths increases, a space for providing the paths is required, which increases the size of the wiring board and increases the manufacturing cost of the wiring board to form more via conductors 26. End up.

Japanese Patent No. 4219541

  According to the present invention, a grounding through-hole conductor and a grounding external connection pad connected thereto, a power supply through-hole conductor and a power supply external connecting pad connected thereto are arranged adjacent to each other. In the case of providing two via connection paths for connecting one grounding or power supply external connection pad and the through-hole conductor connected thereto, in the external connection pad and the through-hole conductor connected to the via-connection path An object of the present invention is to provide a small-sized wiring board that can suppress a decrease in potential to a very low level, and that can sufficiently operate a semiconductor integrated circuit element by sufficiently supplying power to the semiconductor integrated circuit element. .

The wiring board of the present invention is provided adjacent to each other so as to penetrate through the core substrate and an insulating substrate formed by laminating a plurality of insulating layers on the upper and lower surfaces of the core substrate, and is connected to a ground potential. A grounding through-hole conductor and a power-supply through-hole conductor connected to a power supply potential are provided adjacent to each other on the lower surface of the insulating substrate, and the grounding through-hole conductor is provided below the grounding through-hole conductor. and external connection pads for power supply connected to the through-hole conductors for the power supply below the external connection pads and through-hole conductors for the power supply for grounding connected to the through-hole conductor, through for one of the power supply Two holes and one grounding through-hole are provided so as to penetrate the insulating layer on the lower surface side, and the grounding through-hole conductor and the contact are formed. Grounding via connection path for connecting ground external connection pads on a one-to-one basis, and power supply via connection path for connecting the power supply through-hole conductor and the power supply external connection pads on a one-to-one basis The grounding via connection path and the power supply via connection path, which are provided two by two , are arranged so as to be offset from each other in a direction facing each other. It is.

According to the wiring board of the present invention, the two via connection paths for grounding that connect the grounding through-hole conductors connected to the grounding potential and the grounding external connection pads connected to the grounding one-to-one relationship on a one-to-one basis. and two via connection paths for power supply connecting the external connection pads for power supply connected to the through-hole conductors for power supply connected to the power source potential one-to-one, with adjacent ones to each other Since they are arranged so as to be offset in the directions facing each other, the ground via connection path and the power supply via connection path that are provided two by two are in close proximity to each other. Even if transient coupling current flows between these grounding and power supply through-hole conductors and the grounding and power supply external connection pads connected to them, the electromagnetic force between them is increased. Return by join The path is formed well, and the potential drop between them can be suppressed to a very small level. Therefore, according to the wiring board of the present invention, it is possible to provide a small-sized wiring board capable of satisfactorily operating the semiconductor integrated circuit element by supplying sufficient power to the mounted semiconductor integrated circuit element. it can.

FIG. 1 is a schematic cross-sectional view showing an example of an embodiment of a wiring board according to the present invention. FIG. 2 is a perspective view of a main part of the wiring board shown in FIG. FIG. 3 is a schematic cross-sectional view of a conventional wiring board. 4 is a perspective view of a main part of the wiring board shown in FIG.

  Next, an example of an embodiment of the wiring board according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view showing a wiring board of this example formed by a build-up method, and FIG. In FIG. 1, hatching is omitted. Further, in FIG. 2, only a part necessary for facilitating understanding of the via connection path in the wiring board of this example is shown, and a part is shown by a broken line.

  As shown in FIG. 1, the wiring board of this example includes an insulating substrate 10 in which build-up insulating layers 2 are laminated on the upper and lower surfaces of a core substrate 1. A mounting portion 10a for mounting the semiconductor integrated circuit element S is formed at the center of the upper surface of the insulating substrate 10, and the lower surface of the insulating substrate 10 serves as a connection surface for connection to an external electric circuit substrate. Yes.

  The core substrate 1 has a thickness of about 50 to 800 μm, and is made of an electrically insulating material in which a glass cloth in which glass fiber bundles are woven vertically and horizontally is impregnated with a thermosetting resin such as bismaleimide triazine resin or epoxy resin. A core conductor layer 4 made of copper foil or a copper plating layer is deposited on the upper and lower surfaces of 1 and a plurality of through-hole conductors 5 penetrating from the upper surface to the lower surface of the insulating substrate 1 are formed. The diameter of the through-hole conductor 5 is about 100 to 300 μm, and the inside is filled with resin.

  The buildup insulating layer 2 is made of an insulating material containing a thermosetting resin such as an epoxy resin, and a buildup conductor layer 3 made of a copper plating layer is deposited on the surface thereof. Further, a plurality of via hole conductors 6 penetrating each insulating layer 2 are formed. The build-up conductor layer 3 is electrically connected to the through-hole conductor 5 while being connected to each other via the via-hole conductor 6. Further, a part of the buildup conductor layer 3 deposited on the outermost buildup insulating layer 2 on the upper surface side is electrically connected to the electrode terminal T of the semiconductor integrated circuit element S in the mounting portion 10a. The circular semiconductor element connection pads 7 are formed, and these semiconductor element connection pads 7 are arranged in a lattice pattern corresponding to the electrode terminals T of the semiconductor integrated circuit element S. Also, a part of the lower surface side deposited on the outermost buildup insulating layer 2 is a circular external connection pad 8 that is electrically connected to the wiring conductor of the external electric circuit board. A plurality of grids 8 are formed in a grid.

  Further, a solder resist layer 9 for exposing the semiconductor element connection pads 7 and the external connection pads 8 is deposited on the outermost buildup insulating layer 2 and the buildup conductor layer 3 thereon. The electrode terminal T of the semiconductor integrated circuit element S is electrically connected to the exposed portion of the semiconductor element connection pad 9, and the wiring conductor of the external electric circuit board (not shown) is connected to the exposed portion of the external connection pad 8 via the solder ball. Are electrically connected.

  The semiconductor element connection pad 7 and the external connection pad 8 are provided for supplying a ground potential to the semiconductor element S, for supplying a power supply potential to the semiconductor element S, and between the semiconductor element S and the outside. For transmitting and receiving signals between them, and each of them is electrically connected to each other through a corresponding through-hole conductor 5 and via conductor 6.

  In the wiring board of this example, as shown in FIG. 2, the grounding through-hole conductor 5G, the grounding external connection pad 8G connected thereto, the power-supplying through-hole conductor 5P and the power supply through-hole conductor 5P are connected thereto. The external connection pads 8P for power supply are arranged adjacent to each other.

  The grounding through-hole conductor 5G is electrically connected to the grounding semiconductor element connection pad 7G via one via connection path 6Ga including the upper surface side via 6a, the upper surface side via land 3La, and the upper surface side through hole land 4La. Connected. Further, the power supply through-hole conductor 5P is electrically connected to the power supply semiconductor element connection pad 7P through one via connection path 6Pa including the via 6a, via land 3La, and through-hole land 4La on the upper surface side. ing. The via land 3La is formed from the buildup conductor layer 3 on the upper surface side, and the through-hole land 4La is formed from the core conductor layer 4 on the upper surface side.

  On the other hand, the grounding external connection pad 8G is positioned below the grounding through-hole conductor 5G, and includes two via connection paths including the via 6b on the lower surface side, the via land 3Lb on the lower surface side, and the through-hole land 4Lb on the lower surface side. It is electrically connected to the grounding through-hole conductor 5G via 6Gb. The power supply external connection pad 8P is positioned below the power supply through-hole conductor 5P, and includes two via connection paths including a via 6b on the lower surface side, a via land 3Lb on the lower surface side, and a through hole land 4Lb on the lower surface side. It is electrically connected to the through-hole conductor 5P for power supply via 6Pb. The via land 3Lb is formed from the build-up conductor layer 3 on the lower surface side, and the through-hole land 4Lb is formed from the core conductor layer 4 on the lower surface side.

  In the wiring board of this example, two via connection paths 6Gb and 6Pb for connecting one grounding or power supply external connection pads 8G and 8P and the through-hole conductors 5G and 5P connected thereto are , Each of which is provided so as to be offset from each other at a position of 90 ° around the through-hole conductors 5G and 5P, and between these two adjacent external connection pads 8G and 8P and the through-hole conductors 5G and 5P, The respective via connection paths 6Gb and 6Pb are arranged on opposite sides. That is, the through-hole conductor 5G connected to the ground potential and the grounding external connection pad 8G connected to the grounding via connection path 6Gb for connecting at two points respectively and the through-hole connected to the power supply potential Power supply via connection paths 6Pb for connecting the conductor 5P and the power supply external connection pad 8P connected to the conductor 5P at two locations are arranged so as to be offset in the direction facing each other between the adjacent ones. That is important.

  According to the wiring board of this example, the via connection paths 6Gb and 6Gb for grounding that connect the through-hole conductor 5G connected to the ground potential and the external connection pads 8G for grounding connected to each other at two points respectively. Further, the power supply via connection paths 6Pb for connecting the through-hole conductor 5P connected to the power supply potential and the power supply external connection pads 8P connected to the power supply potential at two places respectively are mutually adjacent to each other. Since it is arranged so as to be offset in the facing direction, the grounding via connection path 6Gb and the power supply via connection path 6Pb are close to each other, and as a result, the electromagnetic coupling between the two becomes stronger, A transient current flows between the grounding and power supply through-hole conductors 5G and 5P and the grounding and power supply external connection pads 8G and 8P connected thereto. Even so, a return path by electromagnetic coupling between the via connection path 6Gb for grounding and the via connection path 6Pb for power supply is well formed and connected to the through-hole conductors 5G and 5P for grounding and power supply. The potential drop between the grounding and power supply external connection pads 8G and 8P can be suppressed to an extremely low level. Therefore, according to the wiring board of this example, a small-sized wiring board capable of sufficiently operating the semiconductor integrated circuit element S by supplying sufficient power to the mounted semiconductor integrated circuit element S is provided. be able to. The inventor creates a simulation model of the present invention that models the wiring board of this example shown in FIG. 2 and a conventional simulation model that models the conventional wiring board shown in FIG. According to the simulation performed using the density simulator, the voltage drop when the transient current flows in the power supply to the conductor integrated circuit element S is the same as that in the via connection path of the present invention shown in FIG. The result which improved 0.2-0.3mV per 1V rather than the via | veer connection path | route has been confirmed.

DESCRIPTION OF SYMBOLS 1 Core substrate 2 Insulation layer 5G Through-hole conductor for grounding 5P Through-hole conductor for power supply 6Gb Via connection path for ground 6Pb Via connection path for power supply 8G External connection pad for grounding 8P External connection pad for power supply 10 Insulation substrate

Claims (1)

An insulating substrate formed by laminating a plurality of insulating layers on the upper and lower surfaces of the core substrate, and a grounding through-hole conductor provided adjacent to each other so as to penetrate the core substrate, and connected to a grounding potential, and A through-hole conductor for power supply connected to a power supply potential is provided adjacent to each other on the lower surface of the insulating substrate, and is connected to the through-hole conductor for grounding below the through-hole conductor for grounding and external connection pads for below the external connection pads and through-hole conductors for the power supply for the ground connected to the through-hole conductors for the power supply, through-holes and one for the ground for one of said power supply The through -hole conductor for grounding and the external connection pad for grounding are provided so that two through-holes pass through the insulating layer on the lower surface side. Wiring board having a via connection paths for power supply connecting the external connection pads on a one-to-one for the the via connection path and the through-hole conductors for the supply of ground power supply connected in a one-to-one bets The grounding via connection path and the power supply via connection path, which are provided two by two , are arranged so as to be offset in directions facing each other.

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