JP6686499B2 - Heat dissipation structure of semiconductor integrated circuit device, semiconductor integrated circuit device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a heat dissipation structure of a semiconductor integrated circuit device, a semiconductor integrated circuit device and a manufacturing method thereof, and more particularly to a technique for improving a heat dissipation effect.

  In a product such as a power supply circuit that allows a large amount of current to flow, a problem may occur due to heat generated in an IC (Integrated Circuit) for the power supply circuit. However, although the miniaturization of the IC is promoted, the main heat dissipation path is only dependent on the heat conduction from each terminal of the IC, so that the heat dissipation is restricted and the temperature guarantee range of the product or the IC is hindered. May be

  Therefore, a configuration is known in which a heat dissipation plate is fixed to a circuit board on which electronic components are mounted, and a heat dissipation sheet member is sandwiched between the heat dissipation plate and the electronic components (for example, see Patent Document 1). In addition, a configuration is known in which a pin fin heat sink is provided on the upper surface of a semiconductor device (see, for example, Patent Document 2).

JP, 2013-219169, A JP-A-6-5751

  However, in the configuration in which the heat dissipation plate (heat dissipation plate) is fixed to the circuit board (printed wiring board), the heat generated by electronic components such as semiconductor integrated circuit elements is mainly transferred to the heat dissipation plate via the circuit board, and Heat is dissipated from the plate. Therefore, the heat dissipation path becomes relatively long, which may hinder the improvement of the heat dissipation effect. Further, the heat radiation path that is transmitted from the semiconductor integrated circuit element to the heat radiation plate via the heat radiation sheet member has the following problems. That is, as the heat radiation sheet member or the adhesive required for providing the pin feet, a structure in which conductive powder is dispersed in resin is generally used. Therefore, their thermal conductivity is insufficient for obtaining a heat dissipation effect because they are due to point contact between the conductive powders. As described above, the conventional configuration has a problem in that it is difficult to obtain a sufficient heat radiation effect capable of reducing a defect due to heat.

  Therefore, an object of the present invention is to provide a heat dissipation structure of a semiconductor integrated circuit element, etc., which can improve the heat dissipation effect.

  In order to achieve the above object, a heat dissipation structure of a semiconductor integrated circuit device according to an aspect of the present invention is a printed wiring board and a semiconductor substrate mounted on the printed wiring board, the semiconductor substrate serving as an element body, A semiconductor integrated circuit element having an integrated circuit on the mounting surface side, and a heat dissipation plate mounted on the top surface side of the semiconductor substrate, the heat dissipation structure of the semiconductor integrated circuit element, wherein the semiconductor integrated circuit element, On the top surface side of the semiconductor substrate, a plurality of columnar conductors, one end of which is in contact with the semiconductor substrate, are provided, and the integrated circuit is thermally connected to the heat dissipation plate via the semiconductor substrate and the columnar conductors. ing.

  Since the columnar conductor is provided on the top surface side of the semiconductor substrate as described above, the heat generated in the integrated circuit can be quickly radiated from the heat sink through the semiconductor substrate and the columnar conductor. Therefore, since the heat radiation path can be shortened, the heat radiation effect can be improved.

  Further, the printed wiring board may be further provided with a heat dissipation auxiliary member that thermally connects the printed wiring board and the heat dissipation plate.

  By mounting the heat dissipation auxiliary member in this manner, the integrated circuit is thermally connected to the heat dissipation plate via the printed wiring board and the heat dissipation auxiliary member. Therefore, the heat generated in the integrated circuit can be dissipated from the heat dissipation plate via the heat dissipation auxiliary member. Therefore, the heat dissipation effect can be further improved by increasing the heat dissipation paths.

  Further, the heat dissipation auxiliary member may be a chip component mounted on the printed wiring board, having an LGA (Land Grid Array) or BGA (Ball Grid Array) electrode.

  Thus, since the heat dissipation auxiliary member is a chip component mounted by the electrodes of the LGA or BGA, the heat generated in the integrated circuit of the semiconductor integrated circuit device is mounted around the semiconductor integrated circuit device. Heat can be dissipated from the heat sink through the components. Further, in the chip component, electrodes are arranged on the mounting surface on the printed wiring board. Therefore, even when a conductive member having a high heat dissipation effect is used as the heat dissipation plate, it is possible to directly contact the chip component and the heat dissipation plate while preventing a short circuit between the electrodes of the chip component. Therefore, the thermal conductivity and heat dissipation effect of the heat dissipation path passing through the chip component can be improved.

  Further, the heat dissipation auxiliary member has electrodes provided from the bottom surface to the top surface at both ends, and the printed wiring board is so arranged that only the electrode at one end when viewed from the top surface side overlaps with the heat dissipation plate. It may be a chip component mounted on.

  As described above, since the heat dissipation auxiliary member is a chip component in which only one electrode overlaps the heat dissipation plate, heat generated in the integrated circuit of the semiconductor integrated circuit device is mounted around the semiconductor integrated circuit device. It is possible to radiate heat from the heat sink through the chip parts. The electrodes of the chip component are provided from the bottom surface to the top surface. For this reason, since the electrode is located relatively close to the heat sink, the thermal conductivity from the electrode to the heat sink can be improved. Further, since only one electrode overlaps the heat sink, even when a conductive member having a high heat dissipation effect is used as the heat sink, the short circuit between the electrodes of the chip part is prevented and the chip part and the heat sink are prevented. Can be directly contacted. Therefore, the thermal conductivity and heat dissipation effect of the heat dissipation path passing through the chip component can be improved.

  Moreover, one end of the columnar conductor may be in direct contact with the semiconductor substrate, and the other end may be in direct contact with the heat dissipation plate.

  As described above, the columnar conductors are in direct contact with the semiconductor substrate and the heat dissipation plate, so that the thermal conductivity can be enhanced as compared with the case where the columnar conductors are in contact with each other via an adhesive having thermal conductivity. Specifically, the adhesive generally has a structure in which conductive powder is dispersed in a resin. Therefore, their thermal conductivity is due to point contact between the conductive powders. On the other hand, according to this aspect, the columnar conductor and the semiconductor substrate, and the columnar conductor and the heat sink are in surface contact with much higher thermal conductivity than in point contact. Therefore, the thermal conductivity of the heat dissipation path can be increased, and the heat dissipation effect can be further improved.

  The present invention can be realized not only as the heat dissipation structure of the semiconductor integrated circuit device described above, but also as the semiconductor integrated circuit device itself. That is, in order to achieve the above object, a semiconductor integrated circuit element according to one embodiment of the present invention is a body of a semiconductor integrated circuit element, and has a semiconductor substrate having an integrated circuit on a mounting surface side, and the semiconductor substrate A plurality of columnar conductors provided on the top surface side and having one end in contact with the semiconductor substrate.

  According to such a semiconductor integrated circuit element, since the columnar conductor is provided on the top surface side of the semiconductor substrate, heat generated in the integrated circuit is transferred to the ceiling of the semiconductor integrated circuit element through the semiconductor substrate and the columnar conductor. It can be quickly guided to the surface side and radiated. That is, since the heat dissipation path can be shortened, the heat dissipation effect can be improved.

  Further, each of the plurality of columnar conductors may have an inverse taper shape whose cross section becomes smaller as it approaches the semiconductor substrate.

  Since each of the plurality of columnar conductors has the inverse tapered shape in this manner, the thermal diffusivity of the columnar conductor is improved. Therefore, the heat dissipation effect can be further improved.

  Further, the semiconductor integrated circuit element further has an insulating layer provided on the top surface side of the semiconductor substrate, and the plurality of columnar conductors are via conductors penetrating the insulating layer in the thickness direction. You may decide.

  Since the plurality of columnar conductors are via conductors penetrating the insulating layer in this manner, the strength of the columnar conductor can be increased.

  Further, the insulating layer may be a resin layer containing magnetic powder.

  The insulating layer containing such magnetic powder functions as a magnetic shield. Therefore, it is possible to prevent the noise generated in the integrated circuit from leaking to the outside of the semiconductor integrated circuit device.

  Further, one end of the columnar conductor may be embedded in the top surface of the semiconductor substrate.

  In this way, the columnar conductor is fixed by the semiconductor substrate by having one end embedded in the semiconductor substrate, so that the strength can be increased. Further, the columnar conductor whose one end is embedded in the semiconductor substrate has a larger contact area with the semiconductor substrate as compared with the case where the columnar conductor is not embedded. Therefore, the thermal conductivity from the semiconductor substrate to the columnar conductor is improved, so that the heat dissipation effect of the semiconductor integrated circuit element can be improved.

  The present invention can also be realized as a manufacturing method for manufacturing such a semiconductor integrated circuit element. That is, a method for manufacturing a semiconductor integrated circuit device according to one aspect of the present invention is an element body of the semiconductor integrated circuit device, and an insulating layer is formed on a top surface side of a semiconductor substrate having an integrated circuit on a mounting surface side. A step of forming a plurality of through holes that expose the semiconductor substrate by penetrating the insulating layer; and filling the plurality of through holes with a conductor, the semiconductor substrate being provided on the top surface side, Forming a plurality of columnar conductors, one end of which is in contact with the semiconductor substrate.

  As described above, by manufacturing the columnar conductor by the rewiring process of the semiconductor integrated circuit element, the semiconductor integrated circuit element capable of improving the heat radiation effect can be easily manufactured.

  According to the present invention, the heat dissipation effect of the semiconductor integrated circuit device can be improved.

It is a perspective view showing a heat dissipation structure of a semiconductor integrated circuit element concerning an embodiment. FIG. 4 is an exploded perspective view showing a heat sink separated from other components. It is the top view and sectional drawing which show the heat dissipation structure of a semiconductor integrated circuit element. FIG. 3 is a cross-sectional view of a semiconductor integrated circuit device and a partially enlarged view thereof. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element. FIG. 3 is a cross-sectional view schematically showing how heat from a semiconductor integrated circuit element is transferred in a heat dissipation structure. FIG. 6 is a cross-sectional view and a partially enlarged view of a semiconductor integrated circuit device according to a modification of the embodiment. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element. It is sectional drawing which shows the manufacturing process of a semiconductor integrated circuit element.

  Hereinafter, a heat dissipation structure of a semiconductor integrated circuit device according to an embodiment of the present invention will be described with reference to the drawings. It should be noted that each of the embodiments described below shows a preferred specific example of the present invention. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, manufacturing processes, and order of manufacturing processes shown in the following embodiments are examples, and are not intended to limit the present invention. . Further, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims showing the highest concept are described as arbitrary constituent elements. Also, the sizes or ratios of sizes of the components shown in the figures are not necessarily exact. Further, in the cross-sectional views shown in the following embodiments, for simplification, some of the components are shown as side views, and strictly speaking, components in different cross-sections may be shown and described in the same drawing. . In the following, the numerical range A to B indicates that it is A or more and B or less.

(Embodiment)
FIG. 1A is a perspective view showing a heat dissipation structure 1 of a semiconductor integrated circuit element 10 according to the present embodiment. FIG. 1B is an exploded perspective view showing the heat dissipation plate 20 separated from other components in the heat dissipation structure 1 shown in FIG. 1A.

  In the present embodiment, the thickness direction of the semiconductor integrated circuit device 10 will be described as the Z-axis direction, and the directions perpendicular to the Z-axis direction and orthogonal to each other will be described as the X-axis direction and the Y-axis direction, respectively. The top surface (upper surface) side of the integrated circuit element 10 will be described. However, in the actual use mode, the thickness direction of the semiconductor integrated circuit element 10 may not be the vertical direction. Therefore, in the actual use mode, the top surface side of the semiconductor integrated circuit element 10 is not limited to the top surface side.

  The heat dissipation structure 1 shown in these figures is a heat dissipation structure of the semiconductor integrated circuit element 10 that efficiently dissipates heat generated in the semiconductor integrated circuit element 10. Specifically, the heat dissipation structure 1 dissipates heat generated in the semiconductor integrated circuit element 10 by efficiently conducting it to air or the like. The heat dissipation structure 1 includes a semiconductor integrated circuit element 10, a heat dissipation plate 20, and a printed wiring board 30. Further, on the printed wiring board 30, chip capacitors 41 and 42 and a chip inductor 43 are mounted, and a metal post 44 is further provided.

  The semiconductor integrated circuit element 10 is an IC chip that is mounted on the printed wiring board 30 and has a semiconductor substrate as an element body and an integrated circuit on the mounting surface side of the semiconductor substrate. In the present embodiment, the semiconductor integrated circuit element 10 is arranged so as to entirely overlap the heat sink 20 when viewed from the top surface side. Further, in the present embodiment, the top surface of the semiconductor integrated circuit element 10 is in contact with the heat dissipation plate 20.

  It is preferable that the entire top surface of the semiconductor integrated circuit element 10 is in contact with the heat dissipation plate 20 from the viewpoint of improving the thermal conductivity, but it is sufficient if it is thermally connected to the heat dissipation plate 20. Not limited to For example, the semiconductor integrated circuit element 10 does not need to have a part of its top surface overlapping the heat sink 20 when viewed from the top surface side. The detailed configuration of the semiconductor integrated circuit element 10 will be described later.

  The heat dissipation plate 20 is a heat sink mounted on the top surface side of the semiconductor integrated circuit element 10 and radiating the heat generated in the semiconductor integrated circuit element 10. Specifically, the heat dissipation plate 20 is a plate-shaped member having a plurality of protrusions 20a (heat dissipation fins) protruding upward. In such a heat radiating plate 20, the heat transfer area to the air is promoted by expanding the heat transfer area to the air by the plurality of protrusions 20a, and the heat radiating effect is enhanced.

  In the heat dissipation plate 20 of the present embodiment, a plurality of protrusions 20a extending along the X-axis direction are arranged at equal intervals in the Y-axis direction. However, the heat dissipation plate 20 is not limited to such a configuration, and may have any configuration, for example, the protrusion 20a is extended along the Y-axis direction.

  The material of the heat dissipation plate 20 is not particularly limited, but for example, a metal or alloy containing aluminum as a main component may be used. Further, the configuration of mounting the heat dissipation plate 20 on the top surface side of the semiconductor integrated circuit element 10 is not particularly limited, but, for example, an adhesive for adhering the heat dissipation plate 20 and the semiconductor integrated circuit element 10 or the heat dissipation plate 20 may be used. A fastening member such as a screw that is fastened to the printed wiring board 30 may be used.

  The printed wiring board 30 is a substrate on which the semiconductor integrated circuit element 10 is mounted, and in the present embodiment, various conductors for forming a DCDC converter circuit are provided. The conductor includes a surface electrode for mounting the semiconductor integrated circuit element 10, the chip capacitors 41, 42, and the chip inductor 43 on the printed wiring board 30, and wiring and via conductors for connecting these. .

  The material of the printed wiring board 30 is not particularly limited, but for example, a resin substrate such as an epoxy substrate or a ceramic substrate such as a ferrite substrate may be used.

  The chip capacitors 41 and 42, the chip inductor 43, and the metal post 44 are each an example of a heat dissipation auxiliary member that thermally connects the printed wiring board 30 and the heat dissipation plate 20. For example, it is preferable that these have a portion having a higher thermal conductivity than air, and particularly a portion having a higher thermal conductivity than the semiconductor substrate of the semiconductor integrated circuit element 10.

  These arrangement modes will be further described with reference to FIG. FIG. 2 is a top view and a cross-sectional view showing the heat dissipation structure 1 of the semiconductor integrated circuit element 10 according to the present embodiment. Specifically, (a) of the same figure is a top view of the heat dissipation structure 1 (a view seen from the Z-axis direction plus side), and (b) is a sectional view taken along line bb of (a), (C) is sectional drawing in the cc line of (a). In addition, in the same figure, the heat dissipation plate 20 is shown through for the sake of simplicity of these arrangements.

  As shown in FIG. 2A, the chip capacitors 41 and 42, the chip inductor 43, and the metal post 44 are arranged so as to surround the semiconductor integrated circuit element 10. Specifically, they are arranged so as to be located in different directions with respect to the semiconductor integrated circuit element 10 in a top view. In particular, the chip capacitors 41 and 42 and the chip inductor 43 are arranged at substantially equal positions with the semiconductor integrated circuit element 10 as the center in a top view. With such an arrangement, the heat generated in the semiconductor integrated circuit element 10 can be promptly guided to the heat dissipation plate 20. The term “substantially equal” means not only being completely equal but also being substantially equal. That is, “substantially” includes an error of about several percent. The same applies to other expressions using "abbreviation" hereinafter.

  The arrangement mode of the chip capacitors 41 and 42, the chip inductor 43, and the metal post 44 is not limited to this. For example, even if they are arranged in the same direction as the semiconductor integrated circuit element 10 in a top view. I don't care.

  Each of the chip capacitors 41 and 42 is a chip component having electrodes provided at both ends from the bottom surface to the top surface. In the present embodiment, when viewed from the top surface side (as viewed from the Z-axis direction plus side), The printed wiring board 30 is mounted so that only the electrodes at one end overlap the heat sink 20. Specifically, the chip capacitor 41 has an end face electrode 411 at one end and an end face electrode 412 at the other end, and only the end face electrode 411 overlaps the heat sink 20 when viewed from the top surface side. Are arranged. Further, the chip capacitor 42 has an end face electrode 421 at one end and an end face electrode 422 at the other end, and only the end face electrode 421 is arranged so as to overlap the heat dissipation plate 20 when viewed from the top surface side. ing.

  These chip capacitors 41 and 42 are mounted on the printed wiring board 30 by a solder material or the like, and in the present embodiment, the top surface contacts the heat dissipation plate 20 and the bottom surface contacts the printed wiring board 30.

  The chip inductor 43 is a chip component that has LGA (Land Grid Array) electrodes 431 and 432 and is mounted on the printed wiring board 30. In the present embodiment, the entire chip radiator radiates heat. It is mounted so as to overlap the plate 20. As the element of the chip inductor 43, a multilayer substrate in which magnetic layers such as magnetic ferrite ceramics are laminated can be used. Generally, a substrate made of magnetic ferrite ceramics has a higher thermal conductivity than a semiconductor substrate forming a semiconductor integrated circuit device. Therefore, such a chip inductor 43 is suitable as a heat dissipation auxiliary member.

  The configuration of the chip inductor 43 is not limited to this, and the electrodes 431 and 432 may be BGA (Ball Grid Array). From the viewpoint of heat dissipation, it is preferable that the entire chip inductor 43 (particularly the top surface) overlaps with the heat dissipation plate 20 when viewed from the top surface side, but only part of the chip inductor 43 overlaps with the heat dissipation plate 20. I don't care.

  The metal post 44 is, for example, a metal member in which the bottom end 441 is inserted into the printed wiring board 30 and the top surface abuts on the heat dissipation plate 20. The shape of the metal post 44 is not particularly limited, but is, for example, a taper shape in which the diameter of the bottom surface side end portion 441 is small and the cross section becomes smaller as the other portion approaches the top surface. The material of the metal post 44 is not particularly limited, but, for example, a metal or alloy containing aluminum as a main component may be used.

  The heat dissipation structure 1 of the semiconductor integrated circuit element 10 configured as described above can be applied to, for example, a DCDC converter module that converts a DC voltage supplied from a battery into a DC voltage suitable for various circuits and outputs the DC voltage.

  In this case, the semiconductor integrated circuit element 10 is, for example, a switching IC chip that intermittently supplies a current to the chip inductor 43 by switching a built-in switch element (not shown) at a predetermined frequency. The chip capacitor 41 is, for example, an input-side smoothing capacitor having one end connected to the input voltage power supply line and the other end connected to the ground. The chip capacitor 42 is, for example, an output-side smoothing capacitor having one end connected to the output voltage power supply line and the other end connected to the ground.

  The heat dissipation structure 1 is not limited to such a DCDC converter module and may be applied to another electronic circuit module. Alternatively, in the semiconductor integrated circuit device 10, the chip capacitors 41 and 42, and the chip inductor 43, at least one circuit device may form another electronic circuit. That is, for example, the semiconductor integrated circuit element 10 and the chip capacitors 41 and 42 and the chip inductor 43 do not have to be electrically connected.

  Next, the semiconductor integrated circuit element 10 will be described in detail.

  FIG. 3 is a sectional view of the semiconductor integrated circuit device 10 and a partially enlarged view thereof. Specifically, (a) of the figure is a cross-sectional view of the semiconductor integrated circuit element 10 taken along the line III-III of FIG. 2, and (b) is a partially enlarged view of (a).

  As shown in the figure, the semiconductor integrated circuit element 10 has a semiconductor substrate 11 as an element body, and has an integrated circuit on the mounting surface side (bottom surface side, that is, the Z axis direction negative side) of the semiconductor substrate 11. The semiconductor integrated circuit device 10 further includes a mounting surface side rewiring layer 12, a top surface side rewiring layer 13, and an external connection electrode 14.

  As described above, the semiconductor substrate 11 has the integrated circuit on the mounting surface side. The integrated circuit includes an element such as a transistor that forms a switch element, and forms a circuit region 111 on the semiconductor substrate 11. That is, the circuit region 111 is a region defined by the integrated circuit formed by the semiconductor inner layer process, and is formed on the mounting surface side from the center in the thickness direction of the semiconductor substrate 11, for example.

  The circuit region 111 is formed by doping impurities from the mounting surface side of the semiconductor substrate 11 in the semiconductor inner layer process. Therefore, the circuit region 111 is not formed on the top surface of the semiconductor substrate 11. That is, the semiconductor substrate 11 has the intermediate region 112 where the integrated circuit is not formed between the top surface and the circuit region 111. For example, no conductor such as a via conductor and a wiring conductor is formed in this intermediate region 112.

  The semiconductor substrate 11 may be a semiconductor substrate used in a general semiconductor integrated circuit element, and the material is not particularly limited, but a silicon substrate or the like may be used, for example.

  The mounting surface side rewiring layer 12 is a wiring layer provided on the mounting surface side of the semiconductor substrate 11, and is provided on substantially the entire mounting surface side of the semiconductor substrate 11 in which the circuit region 111 is formed. The mounting surface side redistribution layer 12 has, for example, an insulating layer 121 and various conductors. The various conductors include a wiring conductor 122 which is an in-plane conductor provided along the main surface of the semiconductor substrate 11 and a via conductor 123 provided in a direction (Z-axis direction) perpendicular to the main surface. Be done. By connecting the integrated circuit and the external connection electrode 14 with these various conductors, the circuit configuration of the semiconductor integrated circuit element 10 (for example, the circuit configuration of the switching IC chip) is realized.

  The mounting surface side rewiring layer 12 is formed by a semiconductor rewiring process in the present embodiment. Although the material of the mounting surface side redistribution layer 12 is not particularly limited, for example, an epoxy resin may be used as the insulating layer 121, and silver or copper may be used as various conductors.

  The top surface side rewiring layer 13 is a wiring layer provided on the top surface side of the semiconductor substrate 11, and is provided on substantially the entire top surface side of the semiconductor substrate 11. That is, the top surface side redistribution layer 13 is provided on the opposite side of the semiconductor substrate 11 from the circuit region 111. In the present embodiment, the top surface side redistribution layer 13 has an insulating layer 131 and a plurality of via conductors 133.

  The insulating layer 131 is provided on the top surface side of the semiconductor substrate 11, and is a resin layer containing magnetic powder in the present embodiment. As the magnetic powder, for example, ferrite containing iron oxide as a main component and containing at least one of zinc, nickel and copper is used. Further, the material of the resin is not particularly limited, but for example, an epoxy resin may be used as in the case of the insulating layer 121 of the mounting surface side rewiring layer 12.

  The plurality of via conductors 133 are a plurality of columnar conductors provided on the top surface side of the semiconductor substrate 11 and having one end (here, the end on the negative side in the Z-axis direction) in contact with the semiconductor substrate 11. In the present embodiment, one end of the via conductor 133 is in direct contact with the semiconductor substrate 11, and the other end (here, the end on the Z axis direction positive side) is in direct contact with the heat sink 20. 131 is penetrated in the thickness direction. In addition, each of the plurality of via conductors 133 has an inverse taper shape whose cross section becomes smaller as it gets closer to the semiconductor substrate 11.

  The via conductor 133 is, for example, a reverse-tapered columnar shape in which the diameter (w in the drawing) of the top surface 133a is approximately circular and the height (ha in the drawing) is 30 to 200 μm. . The shape of the via conductor 133 is not limited to this. For example, the cross-sectional shape of the via conductor 133 in a virtual plane along the main surface of the semiconductor substrate 11 may be a substantially rectangular columnar shape.

  The top surface 133 a of the via conductor 133 projects toward the heat dissipation plate 20 by a height hb. That is, when the bottom surface 133 b of the via conductor 133 is in contact with the top surface of the semiconductor substrate 11, the height ha of the via conductor 133 is higher than the thickness of the insulating layer 131. The via conductor 133 does not have to project toward the heat dissipation plate 20, and for example, the height of the via conductor 133 may be lower than the thickness of the insulating layer 131. However, from the viewpoint of heat conduction from the via conductor 133 to the heat dissipation plate 20, it is preferable that the gap between the via conductor 133 and the heat dissipation plate 20 is small. For this reason, the height of the via conductor 133 is equal to or larger than the thickness of the insulating layer 131. Is preferred.

  Further, for example, the plurality of via conductors 133 are evenly scattered on the top surface side rewiring layer 13, and the gaps p between adjacent via conductors 133 are arranged at equal intervals of 100 to 300 μm. Further, when viewed from the Z axis direction plus side, at least one of the plurality of via conductors 133 is arranged so as to overlap the circuit region 111 (that is, the integrated circuit).

  Further, for example, the top surfaces 133a of the plurality of via conductors 133 form the same plane. That is, in the present embodiment, the gap between the bottom surface of the heat dissipation plate 20 and the plurality of via conductors 133 is set to be substantially constant (here, there is no gap).

  As described above, the via conductor 133 provided in the top surface side rewiring layer 13 is electrically connected to the integrated circuit (circuit area 111) as compared with the via conductor 123 provided in the mounting surface side rewiring layer 12. The difference is that they are not thermally connected but are thermally connected. That is, the via conductor 133 is not a conductor for electrically connecting the integrated circuit and the external connection electrode 14, but a conductor for radiating heat generated in the integrated circuit. Therefore, the via conductor 133 is provided so as not to penetrate the semiconductor substrate 11. That is, the top surface and the bottom surface of the semiconductor substrate 11 are insulated, and further, the top surface and the bottom surface of the semiconductor integrated circuit element 10 are also insulated. Note that the semiconductor substrate 11 needs to be insulated at least in the circuit region 111, and the top surface and the bottom surface may be electrically connected by a conductor provided in a region different from the circuit region 111.

  The material of the via conductor 133 is not particularly limited, but, for example, like the various conductors of the mounting surface side redistribution layer 12, silver or copper having high thermal conductivity may be used.

  In the present embodiment, such a top surface side redistribution layer 13 is formed by a semiconductor redistribution process similarly to the mounting surface side redistribution layer 12.

  The external connection electrode 14 is an electrode for mounting the semiconductor integrated circuit element 10 on the printed wiring board 30, and is, for example, a solder bump provided on the bottom surface of the mounting surface side rewiring layer 12.

  As described above, the semiconductor integrated circuit device 10 is an element body of the semiconductor integrated circuit device 10 and has the semiconductor substrate 11 having the integrated circuit (that is, the circuit region 111) on the mounting surface side and the top surface side of the semiconductor substrate 11. A plurality of via conductors 133, one end of which is in contact with the semiconductor substrate 11. The integrated circuit is thermally connected to the heat dissipation plate 20 via the semiconductor substrate 11 and the via conductor 133. Therefore, the heat generated in the integrated circuit can be radiated from the heat dissipation plate 20 via the semiconductor substrate 11 and the via conductor 133.

  Therefore, the semiconductor integrated circuit element 10 can reduce defects caused by heat generated in the integrated circuit even when a circuit that generates a large amount of heat is provided as the integrated circuit. Therefore, the semiconductor integrated circuit element 10 is particularly suitable as a power IC chip used in a power module in which a relatively large current flows, such as a DCDC converter module.

  Next, a manufacturing process (manufacturing method) of the semiconductor integrated circuit element 10 will be described.

  In the manufacturing process of the semiconductor integrated circuit element 10 according to the present embodiment, the via conductor 133 is formed by the semiconductor rewiring process. Thereby, the semiconductor integrated circuit element 10 capable of improving the heat radiation effect can be easily manufactured.

  4A to 4D are cross-sectional views showing the manufacturing process of the semiconductor integrated circuit element 10 according to the present embodiment. In addition, here, the process up to the step of forming the external connection electrode 14 in the semiconductor integrated circuit element 10 is shown.

  First, a semiconductor substrate 11 which is an element of the semiconductor integrated circuit element 10 and has an integrated circuit (that is, a circuit region 111) on the mounting surface side is prepared. That is, the semiconductor substrate 11 after the inner layer process is prepared. In the present embodiment, as shown in FIG. 4A, a semiconductor substrate 11 having a mounting surface side rewiring layer 12 formed on the mounting surface side is prepared. Next, for example, the top surface side of the semiconductor substrate 11 is polished (mirror polish).

  Next, as shown in FIG. 4B, the insulating layer 131A is formed on the top surface side of the semiconductor substrate 11. Specifically, in the present embodiment, the insulating layer 131A is formed on the top surface side of the semiconductor substrate 11 by applying an insulating resin before curing by spin coating or the like. As a result, the entire top surface of the semiconductor substrate 11 is covered with the insulating layer 131A. Note that the process of forming the insulating layer 131A is not limited to this.

  Next, as illustrated in FIG. 4C, a plurality of through holes 131B that penetrate the insulating layer (here, the insulating layer 131A) and expose the semiconductor substrate 11 are formed. Specifically, in this embodiment, a plurality of through holes 131B are formed by applying a resist (not shown) on the insulating layer 131A and performing photolithography or etching. Note that the step of forming the insulating layer 131 is not limited to this, and for example, the plurality of through holes 131B may be formed by making a hole in the insulating layer 131A from the top surface side with a laser.

  Next, as shown in FIG. 4D, the plurality of through holes 131B are filled with a conductor to form a plurality of via conductors 133 provided on the top surface side of the semiconductor substrate 11 and having one end in contact with the semiconductor substrate 11. Specifically, in the present embodiment, the via conductor 133 penetrating the insulating layer 131 is formed by filling the through hole 131B with a paste-like conductor forming the via conductor 133 and removing the resist. . The step of filling the through hole 131B with the conductor is not limited to this, and may be filled with, for example, plating. The insulating layer 131 may be removed by etching, for example, if necessary.

  Finally, by forming the external connection electrode 14 on the bottom surface of the mounting surface side redistribution layer 12, the semiconductor integrated circuit element 10 described above is formed.

  Thus, in the present embodiment, the plurality of via conductors 133 are formed by the rewiring process after the semiconductor inner layer process. In the above description, the top surface side rewiring process for forming the via conductor 133 is performed after the mounting surface side rewiring process for forming the mounting surface side rewiring layer 12. However, this order is not particularly limited, and for example, the top surface side rewiring process may be performed before the mounting surface side rewiring process.

  Effects and the like of the heat dissipation structure 1 of the semiconductor integrated circuit element 10 according to the present embodiment described above will be described with reference to FIG.

  FIG. 5 is a cross-sectional view schematically showing how heat from semiconductor integrated circuit element 10 is transferred in heat dissipation structure 1 according to the present embodiment. Specifically, FIG. 1A is a sectional view of the heat dissipation structure 1 taken along the line VV in FIG. The thickness of the arrow indicates an example of the amount of heat transferred, and for example, the thicker the arrow, the greater the heat transferred.

  In the heat dissipation structure 1 according to the present embodiment, the columnar conductor (via conductor 133 in the present embodiment) is provided on the top surface side of the semiconductor substrate 11, so that the heat generated in the integrated circuit is transferred to the semiconductor substrate 11 and the semiconductor substrate 11. It is possible to quickly dissipate heat from the heat dissipation plate 20 via the columnar conductor. Therefore, since the heat radiation path can be shortened, the heat radiation effect can be improved.

  Further, in the heat dissipation structure 1 according to the present embodiment, the heat dissipation auxiliary member (in the present embodiment, the chip capacitors 41 and 42, the chip inductor 43, and the metal post 44) is mounted, so that the integrated circuit is printed wiring. It is thermally connected to the heat dissipation plate 20 through the plate 30 and the heat dissipation auxiliary member. Therefore, the heat generated in the integrated circuit can be dissipated from the heat dissipation plate 20 via the heat dissipation auxiliary member. Therefore, the heat dissipation effect can be further improved by increasing the heat dissipation paths.

  Further, in the heat dissipation structure 1 according to the present embodiment, since the heat dissipation auxiliary member is the chip component (here, the chip inductor 43) mounted by the electrode of the LGA or BGA, the heat dissipation auxiliary member is generated in the integrated circuit of the semiconductor integrated circuit element 10. The generated heat can be dissipated from the heat dissipation plate 20 through the chip component mounted around the semiconductor integrated circuit element 10. Further, in the chip component, electrodes are arranged on the mounting surface on the printed wiring board 30. Therefore, even when a conductive member having a high heat dissipation effect is used as the heat dissipation plate 20, it is possible to directly contact the chip part and the heat dissipation plate 20 while preventing a short circuit between the electrodes of the chip part. Therefore, the thermal conductivity and heat dissipation effect of the heat dissipation path passing through the chip component can be improved.

  Further, in the heat dissipation structure 1 according to the present embodiment, the heat dissipation auxiliary member is the chip component (here, the chip capacitors 41 and 42) in which only one electrode overlaps the heat dissipation plate 20, so that the semiconductor integrated circuit element 10 has The heat generated in the integrated circuit can be radiated from the heat dissipation plate 20 via the chip component mounted around the semiconductor integrated circuit element 10. The electrodes of the chip component (here, the end surface electrodes 411, 412, 421, 422) are provided from the bottom surface to the top surface. For this reason, since the electrodes are located to a position relatively close to the heat sink 20, heat conductivity from the electrodes to the heat sink 20 can be enhanced. Further, since only one electrode (here, the end surface electrode 411 of the chip capacitor 41 and the end surface electrode 421 of the chip capacitor 42) overlaps the heat dissipation plate 20, a conductive member having a high heat dissipation effect is used as the heat dissipation plate 20. Even in such a case, the chip component and the heat sink 20 can be brought into direct contact with each other while preventing a short circuit between the electrodes of the chip component. Therefore, the thermal conductivity and heat dissipation effect of the heat dissipation path passing through the chip component can be improved.

  Further, in the heat dissipation structure 1 according to the present embodiment, since the columnar conductors are in direct contact with the semiconductor substrate 11 and the heat dissipation plate 20, compared with the case where they are in contact with each other via an adhesive having thermal conductivity. Therefore, the thermal conductivity can be improved. Specifically, the adhesive generally has a structure in which conductive powder is dispersed in a resin. Therefore, their thermal conductivity is due to point contact between the conductive powders. On the other hand, according to this aspect, the columnar conductor and the semiconductor substrate 11, and the columnar conductor and the heat dissipation plate 20 are in surface contact with much higher thermal conductivity than in point contact. Therefore, the thermal conductivity of the heat dissipation path can be increased, and the heat dissipation effect can be further improved.

  Further, according to the semiconductor integrated circuit element 10 of the present embodiment, since the columnar conductor is provided on the top surface side of the semiconductor substrate 11, heat generated in the integrated circuit is transmitted through the semiconductor substrate 11 and the columnar conductor. Thus, the semiconductor integrated circuit element 10 can be quickly guided to the top surface side and radiated. That is, since the heat dissipation path can be shortened, the heat dissipation effect can be improved.

  Further, in the semiconductor integrated circuit device 10 according to the present embodiment, each of the plurality of columnar conductors has an inverse tapered shape, so that the heat diffusion property in the columnar conductor is improved. Therefore, the heat dissipation effect can be further improved.

  Further, in the semiconductor integrated circuit element 10 according to the present embodiment, since the plurality of columnar conductors are the via conductors 133 penetrating the insulating layer 131, the strength of the columnar conductors can be increased.

  Further, in the semiconductor integrated circuit element 10 according to the present embodiment, the insulating layer 131 containing magnetic powder functions as a magnetic shield. Therefore, leakage of noise generated in the integrated circuit to the outside of the semiconductor integrated circuit element 10 can be suppressed.

  In addition, in the present embodiment, since a plurality of columnar conductors are scattered, it is possible to suppress the occurrence of cracks or the like due to the difference in thermal expansion coefficient between the columnar conductor and the semiconductor substrate 11.

  Further, in the present embodiment, the plurality of columnar conductors and the circuit region 111 are arranged so as to overlap each other in a top view. Thereby, the heat generated in the integrated circuit can be quickly conducted to the heat dissipation plate 20 through the columnar conductor to be dissipated.

  Further, for example, if a through-hole via for heat radiation that penetrates the semiconductor substrate 11 is provided instead of the columnar conductor according to the present embodiment, the integrated circuit may be damaged when the through-via is located in the circuit region 111. On the other hand, if a through via is provided without damaging the integrated circuit, it is necessary to form the integrated circuit while avoiding the through via, which may lead to an increase in chip size due to an increase in the area of the circuit region 111. There is. On the other hand, in the present embodiment, the plurality of columnar conductors are provided so as not to penetrate the semiconductor substrate 11. As a result, the chip size (size of the semiconductor integrated circuit element 10) can be reduced without damaging the integrated circuit.

  Further, according to the method of manufacturing the semiconductor integrated circuit device 10 of the present embodiment, the semiconductor integrated circuit device 10 capable of improving the heat dissipation effect can be easily manufactured by manufacturing the columnar conductor by the rewiring process of the semiconductor integrated circuit device 10. Can be manufactured.

(Modification)
In the above embodiment, the semiconductor integrated circuit element 10 has the via conductor 133 penetrating the insulating layer 131. However, the configuration of the semiconductor integrated circuit element is not limited to this. Therefore, the semiconductor integrated circuit element according to the modification of the embodiment will be described in detail below.

  FIG. 6 is a cross-sectional view and a partially enlarged view of a semiconductor integrated circuit element 210 according to this modification. Specifically, (a) of the figure is a cross-sectional view of the semiconductor integrated circuit element 210 corresponding to the line III-III in FIG. 2, and (b) is a partially enlarged view of (a).

  The semiconductor integrated circuit device 210 shown in the figure is different from the semiconductor integrated circuit device 10 shown in FIG. 3 in that one end of the via conductor 233 is embedded in the top surface of the semiconductor substrate 21. That is, the semiconductor substrate 21 of the present modified example is provided with the concave portion 21a in which the via conductor 233 is embedded on the top surface, as compared with the semiconductor substrate 11 having a flat top surface.

  With such a configuration, the via conductor 233 projects toward the top surface of the semiconductor integrated circuit element 210 by a height hc (here, hc> hb).

  Moreover, the top surface side redistribution layer 23 of the present modification does not have the insulating layer 131 as compared with the top surface side redistribution layer 13 of the embodiment. That is, the via conductor 233 of the present modification is a columnar conductor provided without penetrating the insulating layer. That is, the side surface of the via conductor 233 is exposed except for the portion embedded in the recess 21a.

  Even in the semiconductor integrated circuit element 210 configured as described above, since the columnar conductor (via conductor 233 in this modification) is provided on the top surface side of the semiconductor substrate 21, the integrated circuit (here, the circuit) is provided. The heat generated in the region 111) can be quickly dissipated from the heat dissipation plate 20 via the semiconductor substrate 21 and the columnar conductor. Therefore, as in the embodiment, the heat radiation path can be shortened, and the heat radiation effect can be improved.

  Further, in this modification, the columnar conductor is fixed by the semiconductor substrate 21 because one end thereof is embedded in the semiconductor substrate 21, so that the strength can be increased. Further, the columnar conductor whose one end is embedded in the semiconductor substrate 21 has a larger contact area with the semiconductor substrate 21 as compared with the case where the columnar conductor is not embedded. Therefore, the thermal conductivity from the semiconductor substrate 21 to the columnar conductor is improved, so that the heat dissipation effect of the semiconductor integrated circuit element 210 can be further improved.

  Further, in this modification, the side surface of the protruding portion of the columnar conductor (that is, the side surface of the portion not embedded in the semiconductor substrate 21) is exposed. Therefore, heat exchange with air is also performed on the side surface of the columnar conductor, and the columnar conductor itself also functions as a heat sink. Therefore, the heat dissipation effect of the semiconductor integrated circuit device 210 can be further improved.

  Such a semiconductor integrated circuit device 210 can be manufactured by the following manufacturing process.

  7A to 7D are cross-sectional views showing the manufacturing process of the semiconductor integrated circuit element 210 according to this modification. In addition, here, the process before forming the external connection electrode 14 in the semiconductor integrated circuit element 210 is shown.

  First, as shown in FIG. 7A, a resist 231 is applied on the top surface side of the semiconductor substrate 21A to be the semiconductor substrate 21 by spin coating or the like.

  Next, as shown in FIG. 7B, a plurality of through holes 231B which penetrate the resist 231 and expose the semiconductor substrate 21A are formed by etching or the like. At this time, in this modification, the recess 21a is formed in the semiconductor substrate 21A by, for example, over-etching. As a result, the semiconductor substrate 21 having the recess 21a formed on the top surface is formed.

  Next, as shown in FIG. 7C, a plurality of via conductors, which are provided on the top surface side of the semiconductor substrate 21 and have one end in contact with the semiconductor substrate 21, by filling the plurality of through holes 231B and the plurality of recesses 21a with a conductor. 233 is formed.

  Then, the resist 231 is removed to expose the side surface of the via conductor 233.

  Finally, by forming the external connection electrode 14 on the bottom surface of the mounting surface side redistribution layer 12, the semiconductor integrated circuit element 210 described above is formed.

  As described above, also in this modification, the plurality of via conductors 233 are formed by the rewiring process after the semiconductor inner layer process. As a result, the semiconductor integrated circuit element 210 capable of improving the heat dissipation effect can be easily manufactured.

(Other modifications)
As described above, the heat dissipation structure of the semiconductor integrated circuit element according to the embodiment and the modified example of the present invention, and the semiconductor integrated circuit element and the manufacturing method thereof have been described. However, the present invention is not limited to the individual embodiments and the modified examples. Not limited. Unless departing from the gist of the present invention, various modifications that those skilled in the art can think of are applied to the present embodiment and its modifications, and also an embodiment constructed by combining the components in different embodiments and its modifications, It may fall within the scope of one or more aspects of the invention.

  For example, in the above description, as the columnar conductor provided on the top surface of the semiconductor substrate, a via conductor formed by a semiconductor rewiring process has been described as an example. However, the example of the columnar conductor is not limited to this, and may be, for example, a conductor member formed by sheet metal working.

  In the above description, the columnar conductor is in direct contact with the semiconductor substrate and the heat dissipation plate 20. However, the columnar conductor may be in contact with at least one of the semiconductor substrate and the heat dissipation plate 20 via, for example, a heat dissipation sheet.

  In the above description, the material of the heat sink 20 may be metal or alloy, but the material is not limited to this. For example, as the material of the heat sink 20, a resin having no conductivity may be used. With such a configuration, even when the heat dissipation plate 20 and the chip capacitor 41 are in direct contact with each other, the heat dissipation plate 20 and both of the end face electrodes 411 and 412 of the chip capacitor 41 overlap each other in a top view. Can be implemented in. The same applies to the end electrodes 421 and 422 of the chip capacitor 42.

  Further, in the above description, the heat dissipation auxiliary member is mounted on the printed wiring board 30, but it does not have to be mounted.

  Further, in the above description, the columnar conductor (via conductor in the above description) is assumed to have an inverse taper shape, but the present invention is not limited to this, and for example, it may be a columnar shape whose cross-sectional shape from the bottom surface to the top surface is substantially constant. Absent.

  INDUSTRIAL APPLICABILITY The present invention can be widely used as a heat dissipation structure of a semiconductor integrated circuit element capable of reducing defects by improving a heat dissipation effect, for electronic components such as a DCDC converter module through which a large current flows.

DESCRIPTION OF SYMBOLS 1 Heat dissipation structure 10, 210 Semiconductor integrated circuit element 11, 21, 21A Semiconductor substrate 12 Mounting surface side rewiring layer 13, 23 Top surface side rewiring layer 14 External connection electrode 20 Heat sink 20a Projection 21a Recess 30 Printed wiring board 41 42 chip capacitor 43 chip inductor 44 metal post 111 circuit region 112 intermediate region 121, 131, 131A insulating layer 122 wiring conductor 123, 133, 233 via conductor 131B, 231B through hole 133a top surface 133b bottom surface 411, 412, 421, 422 End electrode 431, 432 Electrode 441 Bottom end

Claims (10)

A printed wiring board,
A semiconductor integrated circuit element mounted on the printed wiring board, having a semiconductor substrate as an element body, and having an integrated circuit on a mounting surface side of the semiconductor substrate,
A heat sink mounted on the top side of the semiconductor substrate,
A heat dissipation structure of a semiconductor integrated circuit device having:
The semiconductor integrated circuit element has a plurality of columnar conductors, one end of which is in contact with the semiconductor substrate, on the top surface side of the semiconductor substrate.
Said integrated circuit via said semiconductor substrate and said columnar conductors are thermally coupled to the heat radiating plate,
Each of the plurality of columnar conductors has an inverse taper shape whose cross section becomes smaller as it approaches the semiconductor substrate,
Heat dissipation structure for semiconductor integrated circuit devices. On the printed wiring board, a heat dissipation auxiliary member that thermally connects the printed wiring board and the heat dissipation plate is further mounted.
A heat dissipation structure for a semiconductor integrated circuit device according to claim 1. The heat dissipation auxiliary member is a chip component mounted on the printed wiring board, having an LGA (Land Grid Array) or BGA (Ball Grid Array) electrode.
The heat dissipation structure for a semiconductor integrated circuit device according to claim 2. The heat dissipation auxiliary member has electrodes provided at both ends from the bottom surface to the top surface, and is mounted on the printed wiring board so that only the electrode at one end when viewed from the top surface side overlaps with the heat dissipation plate. Is a chip component that is
The heat dissipation structure for a semiconductor integrated circuit device according to claim 2. One end of the columnar conductor is in direct contact with the semiconductor substrate and the other end is in direct contact with the heat dissipation plate,
A heat dissipation structure for a semiconductor integrated circuit element according to claim 1. A body of a semiconductor integrated circuit device, a semiconductor substrate having an integrated circuit on the mounting surface side,
A plurality of columnar conductors provided on the top surface side of the semiconductor substrate and having one end in contact with the semiconductor substrate,
Have a,
Each of the plurality of columnar conductors has an inverse taper shape whose cross section becomes smaller as it approaches the semiconductor substrate,
Semiconductor integrated circuit device. The semiconductor integrated circuit element further has an insulating layer provided on the top surface side of the semiconductor substrate,
The plurality of columnar conductors are via conductors that penetrate the insulating layer in the thickness direction,
The semiconductor integrated circuit device according to claim 6 . The insulating layer is a resin layer containing magnetic powder,
The semiconductor integrated circuit device according to claim 7 . One end of the columnar conductor is embedded in the top surface of the semiconductor substrate,
The semiconductor integrated circuit device according to any one of claims 6-8. A method of manufacturing a semiconductor integrated circuit device, comprising:
A step of forming an insulating layer on the top surface side of a semiconductor substrate having an integrated circuit on the mounting surface side, which is an element body of the semiconductor integrated circuit element;
Forming a plurality of through holes that penetrate the insulating layer and expose the semiconductor substrate;
By filling the plurality of through-holes with a conductor, the columnar conductor is provided on the top surface side of the semiconductor substrate and has one end in contact with the semiconductor substrate, and the cross-section becomes smaller as approaching the semiconductor substrate. A step of forming a plurality of columnar conductors having an inverse taper shape ,
A method of manufacturing a semiconductor integrated circuit device, comprising:

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