JP2018164064A - Composite wiring board - Google Patents

Abstract

The present invention provides a composite wiring board in which a connection process between a semiconductor element and a wiring board is simple and signals can be transmitted and received between mounted semiconductor elements in a favorable manner. A first wiring board having a first semiconductor element connection pad on a first mounting portion and a second semiconductor element connection pad on a second mounting portion; Is partially buried between the first mounting portion 10A and the second mounting portion 10B on the upper surface of the wiring substrate 10 and is connected to the electrode of the first semiconductor element 30 by soldering. And a second wiring board 20 having a fourth semiconductor element connection pad 24 capacitively connected to an electrode of the second semiconductor element 40. Thus, the height of the upper surfaces of the third and fourth semiconductor element connection pads 23, 24 is higher than the height of the upper surfaces of the first and second semiconductor element connection pads 13, 14. [Selection diagram] Fig. 1

Description

  The present invention relates to a composite wiring board formed by embedding a second wiring board for connecting a plurality of semiconductor elements in a first wiring board on which a plurality of semiconductor elements are mounted.

  FIG. 3 shows a conventional composite wiring board 200 on which the first semiconductor element 150 and the second semiconductor element 160 are mounted. The composite wiring board 200 includes a first wiring board 110, a second wiring board 120, a third wiring board 130, and a fourth wiring board 140. The first semiconductor element 150 is, for example, a microprocessor. The second semiconductor element 160 is a memory, for example. The first wiring board 110 is a multilayer wiring board. The second wiring board 120 and the third wiring board 130 are interposers. The fourth wiring board 140 is an interconnect bridge.

  The first semiconductor element 150 is mounted on the first wiring board 110 via the second wiring board 120. The second wiring board 120 and the first wiring board 110 are connected by soldering via the first solder bumps 171. The first semiconductor element 150 and the second wiring substrate 120 are soldered via the second solder bump 172.

  The second semiconductor element 160 is mounted on the first wiring board 110 via the third wiring board 130. The third wiring board 130 and the first wiring board 110 are soldered via third solder bumps 173. The second semiconductor element 160 and the third wiring board 130 are solder-connected via the fourth solder bump 174.

  The first semiconductor element 150 and the second semiconductor element 160 are interconnected via a fourth wiring board 140. The first semiconductor element 150 and the fourth wiring board 140 are solder-connected via the fifth solder bump 175. The second semiconductor element 160 and the fourth wiring board 140 are capacitively connected via a gap.

  According to the composite wiring board 200, the first and second semiconductor elements 150 and 160 and the external circuit board are exchanged with the signals by the second and third wiring boards 120 and 130 and the first wiring board 110. Done through. In addition, transmission / reception of signals between the first and second semiconductor elements 150 and 160 is performed via the fourth wiring board 140.

  However, in this composite wiring board 200, the second and third wiring boards 120 and 130 and the first wiring board 110 are soldered via the first and third solder bumps 171 and 173, respectively. The first semiconductor element 150 and the second wiring board 120, the second semiconductor element 160 and the third wiring board 130 are solder-connected through the second and fourth solder bumps 172 and 174, respectively. Further, the fourth wiring board 140 and the first semiconductor element 150 are solder-connected via the fifth solder bump 175. Therefore, the solder connection process between the first and second semiconductor elements 150 and 160 and the first to fourth wiring boards 110 to 140 becomes complicated.

Furthermore, there are three levels of solder connections between the first wiring board 110 and the fourth wiring board 140 via solder bumps 171, 172, and 175, and the first wiring board 110 and the second semiconductor are connected. There are two layers of solder connections between the elements 160 via solder bumps 173 and 174. For this reason, the height variations of the solder connections of these five layers are overlapped, and the gap between the second semiconductor element 160 and the fourth wiring board 140 tends to vary greatly. If there is a large variation in the distance between the second semiconductor element 160 and the fourth wiring board 140, it will be difficult to satisfactorily exchange signals between the two.

US Publication No. 2009/0089466

  SUMMARY OF THE INVENTION An object of the present invention is to provide a composite wiring board in which a connection process between a semiconductor element and a wiring board is simple and signals can be exchanged between the mounted semiconductor elements.

  The composite wiring board of the present invention has a first mounting portion on which the first semiconductor element is mounted and a second mounting portion on which the second semiconductor element is mounted on the upper surface. The plurality of first semiconductor element connection pads soldered to the electrodes of the first semiconductor element via first solder bumps have a first thickness and a first arrangement pitch, and the second mounting A plurality of second semiconductor element connection pads soldered to the electrodes of the second semiconductor element via second solder bumps at the first thickness and the first arrangement pitch. A wiring board and an upper surface of the first wiring board are partially embedded between the first mounting portion and the second mounting portion, and the first mounting portion includes the first mounting portion. A plurality of solder-connected to the electrodes of one semiconductor element via a third solder bump 3 semiconductor element connection pads having a second thickness not greater than the first thickness and a second arrangement pitch smaller than the first arrangement pitch, and the second mounting portion has a second arrangement pitch of the second semiconductor element. A second wiring board having a plurality of fourth semiconductor element connection pads capacitively connected to electrodes at the second thickness and the second arrangement pitch, the composite wiring board comprising: The upper surface of the second wiring board is arranged such that the height of the upper surfaces of the third and fourth semiconductor element connection pads is higher than the height of the upper surfaces of the first and second semiconductor element connection pads. It protrudes upward from the upper surface of one wiring board.

  According to the composite wiring board of the present invention, the first semiconductor is formed on the upper surface of the first wiring board having the first and second semiconductor element connection pads solder-connected to the electrodes of the first and second semiconductor elements. Since the second wiring substrate having the third semiconductor element connection pad that is solder-connected to the electrode of the element and the fourth semiconductor element connection pad that is capacitively connected to the electrode of the second semiconductor element is embedded, The first and second semiconductor elements can be simultaneously mounted on the first and second wiring boards by solder connection. Therefore, the connection between the semiconductor element and the wiring board can be simplified.

  Further, there is no solder connection between the first wiring board and the second wiring board, and the first wiring board and the second semiconductor element are connected by only one layer of solder connection. . Therefore, since there is only one level of solder connection between the second semiconductor element and the second wiring board that are capacitively connected to each other, the variation in the gap between them is small. As a result, it is possible to satisfactorily exchange signals between the two.

Furthermore, the height of the third and fourth semiconductor element connection pads is higher than the height of the first and second semiconductor element connection pads. Therefore, the distance between the third semiconductor element connection pad and the electrode of the first semiconductor element solder-connected to the third semiconductor element connection pad and the fourth semiconductor element connection pad and the electrode of the second semiconductor element capacitively connected thereto The distance gets closer. Therefore, the third semiconductor element connection pad and the electrode of the first semiconductor element can be solder-connected with a small amount of the third solder bump, and capacitively connected to the fourth semiconductor element connection pad and the fourth semiconductor element connection pad. By making the electrode of the second semiconductor element close to each other, the capacitive connection between them can be made good.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a composite wiring board according to the present invention. FIG. 2 is a schematic cross-sectional view showing a state in which a semiconductor element is mounted on the composite wiring board shown in FIG. FIG. 3 is a schematic cross-sectional view of a conventional composite wiring board.

  Next, an embodiment of the composite wiring board of the present invention will be described with reference to FIGS. As shown in FIG. 1, the composite wiring board 100 of this example includes a first wiring board 10 and a second wiring board 20. The first wiring board 10 has a first mounting portion 10A on which the first semiconductor element 30 is mounted and a second mounting portion 10B on which the second semiconductor element 40 is mounted on the upper surface thereof. Yes. The second wiring board 20 is embedded on the upper surface of the first wiring board 10 so as to partially extend between the first mounting part 10A and the second mounting part 10B. The upper surface of the second wiring board 20 protrudes from the upper surface of the first wiring board 10. One of the first and second semiconductor elements 30 and 40 is an MPU and the other is a memory, and exchanges data between them via the second wiring board 20 to exchange data with the outside. Is performed via the first wiring board 10.

  The first wiring board 10 includes a wiring conductor 12 disposed inside and on the surface of an organic material insulating board 11. As a material for forming the insulating substrate 11, a thermosetting resin containing glass cloth or a thermosetting resin without glass cloth is used. The insulating substrate 11 is formed by laminating a plurality of these materials. Moreover, as wiring conductor 12, copper, such as copper foil and copper plating, is used suitably.

  A first semiconductor element connection pad 13 that is solder-connected to an electrode of the first semiconductor element 30 is formed on the first mounting portion 10A of the first wiring board 10. A second semiconductor element connection pad 14 that is solder-connected to the electrode of the second semiconductor element 40 is formed on the second mounting portion 10B of the first wiring board 10. The first and second semiconductor element connection pads 13 and 14 have a disk shape with a diameter of 75 to 100 μm and a height from the upper surface of the insulating substrate 11 of 5 to 25 μm. The arrangement pitch of the first and second semiconductor element connection pads 13 and 14 is about 100 to 150 μm. These semiconductor element connection pads 13 and 14 are made of copper plating.

  External connection pads 15 connected to an external electric circuit board are formed on the lower surface of the first wiring board 10. The external connection pad 15 has a disk shape with a diameter of 300 to 650 μm. The first and second semiconductor element connection pads 13, 14 and the external connection pad 15 are electrically connected to each other through the wiring conductor 12. The external connection pad 15 is made of copper plating.

  The second wiring board 20 is formed by arranging wiring conductors 22 inside and on the surface of the insulating substrate 21. As a material for forming the insulating substrate 21, an inorganic material such as silicon or glass, a thermosetting resin containing glass cloth, a thermosetting resin without glass cloth, or an organic material insulating material such as a liquid crystal polymer is used. . Copper is preferably used as the wiring conductor 22.

A third semiconductor element connection pad 23 that is solder-connected to the electrode of the first semiconductor element 30 is formed on the first mounting portion 10A of the second wiring board 20. A fourth semiconductor element connection pad 24 that is capacitively connected to the electrode of the second semiconductor element 40 is formed on the second mounting portion 10B of the second wiring board 20. The third and fourth semiconductor element connection pads 23 and 24 have a disk shape with a diameter of 25 to 50 μm and a thickness of 5 to 25 μm, and have a thickness equal to or less than the first and second semiconductor element connection pads 13 and 14. It is. The arrangement pitch of the third and fourth semiconductor element connection pads 23 and 24 is 30 to 75 μm. A predetermined number of third semiconductor element connection pads 23 and fourth semiconductor element connection pads 24 are connected to each other via a wiring conductor 22. These third and fourth semiconductor element connection pads 23 and 24 are made of copper plating.

  Further, first solder bumps 51 are welded to the first semiconductor element connection pads 13. A second solder bump 52 is welded to the second semiconductor element connection pad 14. A third solder bump 53 is welded to the third semiconductor element connection pad 23. However, solder bumps are not welded to the fourth semiconductor element connection pads 24. Then, as shown in FIG. 2, the electrodes of the first semiconductor element 30 and the first and third semiconductor element connection pads 13 and 23 are soldered via the first and third solder bumps 51 and 53, respectively. The first and second semiconductor elements 30, 40 are connected by soldering the electrodes of the second semiconductor element 40 and the second semiconductor element connection pads 14 via the second solder bumps 52. It is mounted on the composite wiring board 100. The corresponding electrodes of the second semiconductor element 40 and the fourth semiconductor element connection pad 24 are arranged close to each other so as to face each other.

  At this time, in the composite wiring board 100 of the present example, the first wiring having the first and second semiconductor element connection pads 13 and 14 solder-connected to the electrodes of the first and second semiconductor elements 30 and 40. A third semiconductor element connection pad 23 solder-connected to the electrode of the first semiconductor element 30 and a fourth semiconductor element connection pad 24 capacitively connected to the electrode of the second semiconductor element 40 are formed on the upper surface of the substrate 10. Since the second wiring board 20 is embedded, the first and second semiconductor elements 30 and 40 can be simultaneously mounted on the first and second wiring boards 10 and 20 by solder connection. Therefore, the connection between the semiconductor elements 30 and 40 and the wiring boards 10 and 20 can be simplified.

  Also, there is no solder connection between the first wiring board 10 and the second wiring board 20, and only one level of solder connection is provided between the first wiring board 10 and the second semiconductor element 40. Connected with. Therefore, since there is only one layer of solder connection between the second semiconductor element 40 and the second wiring board 20 that are capacitively connected to each other, the variation in the gap between them is small. As a result, it is possible to satisfactorily exchange signals between the two.

  Further, the height of the upper surfaces of the third and fourth semiconductor element connection pads 23 and 24 is higher than the height of the upper surfaces of the first and second semiconductor element connection pads 13 and 14. Therefore, the distance between the third semiconductor element connection pad 23 and the electrode of the first semiconductor element 30 solder-connected to the third semiconductor element connection pad 23 and the second semiconductor element 40 capacitively connected to the fourth semiconductor element connection pad 24 and this. The distance from the electrode becomes closer. Therefore, the third semiconductor element connection pad 23 and the electrode of the first semiconductor element 30 can be solder-connected with a small amount of the third solder bump 53, and the fourth semiconductor element connection pad 24 and the fourth semiconductor element connection pad 24 can be connected to this. The electrodes of the second semiconductor element 40 that are capacitively connected can be brought close to each other, so that the capacitive connection between them can be made favorable.

  Thus, according to the composite wiring board 100 of the present example, the connection process between the semiconductor elements 30 and 40 and the wiring boards 10 and 20 is simple, and the signal exchange between the mounted semiconductor elements 30 and 40 is excellent. The composite wiring board 100 that can be performed can be provided.

DESCRIPTION OF SYMBOLS 10 1st wiring board 10A 1st mounting part 10B 2nd mounting part 13 1st semiconductor element connection pad 14 2nd semiconductor element connection pad 20 2nd wiring board 23 3rd semiconductor element connection pad 24 1st 4 semiconductor element connection pads 30 first semiconductor element 40 second semiconductor element 100 composite wiring board

Claims (1)

  A first mounting portion on which the first semiconductor element is mounted and a second mounting portion on which the second semiconductor element is mounted are provided on the upper surface, and electrodes of the first semiconductor element are mounted on the first mounting portion. A plurality of first semiconductor element connection pads that are solder-connected to each other via a first solder bump at a first thickness and a first arrangement pitch, and the second semiconductor element is mounted on the second mounting portion. A first wiring board having a plurality of second semiconductor element connection pads soldered to the electrodes via second solder bumps at the first thickness and the first arrangement pitch; and An upper surface of the wiring board is partially embedded between the first mounting portion and the second mounting portion, and the first mounting portion has an electrode connected to the electrode of the first semiconductor element. A plurality of third semiconductor element connection pads soldered via three solder bumps. At a second thickness less than the first thickness and a second arrangement pitch smaller than the first arrangement pitch, and is capacitively connected to the electrode of the second semiconductor element on the second mounting portion. A second wiring board having a plurality of fourth semiconductor element connection pads at the second thickness and the second arrangement pitch, the composite wiring board comprising: The top surface of the first wiring board is such that the height of the top surfaces of the third and fourth semiconductor element connection pads is higher than the height of the top surfaces of the first and second semiconductor element connection pads. A composite wiring board that protrudes upward from the top.