JP2007103796A - Insulating substrate, semiconductor device, and method of manufacturing insulating substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small insulating substrate, while mounting a plurality of electronic components. <P>SOLUTION: A base plate 1 has a three-dimensional structure of U shape which is composed of three flat plates 2 bent approximately at right angle each other, and mounting areas to mount electronic components are sectioned on the surface of three flat plates 2 composing the inside surface the base plate 1, respectively. An insulating layer 3 made up of Al<SB>2</SB>O<SB>3</SB>is formed on the inside surface of the base plate 1 to cover the whole mounting areas of the three flat plates 2, and wiring layers 4 composed of Cu are formed on the surface of the insulating layer 3 corresponding to the mounting areas of each flat plates 2. In an insulating substrate having such a structure, electronic components, such as semiconductor element 5, can be located on the mounting areas of the three flat plates 2 of the base plate 3, respectively. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an insulating substrate, and more particularly to an insulating substrate on which electronic components such as semiconductor elements are mounted.
The present invention also relates to a semiconductor device using such an insulating substrate and a method for manufacturing the insulating substrate.

  For example, Patent Document 1 discloses an insulating substrate in which an insulating layer and a wiring layer are sequentially stacked on the surface of a base plate. With such an insulating substrate, a semiconductor device can be configured by bonding electronic components such as semiconductor elements to the surface of the wiring layer via solder.

JP-A-5-335709

  However, in the above-described insulating substrate, the electronic components are arranged on the same surface of the base plate. Therefore, when a large number of electronic components are to be mounted, it is necessary to use a large-area base plate, and the insulating substrate is large. There was a problem of becoming.

The present invention has been made to solve such problems, and an object thereof is to provide an insulating substrate that can be mounted with a large number of electronic components while being small in size.
Another object of the present invention is to provide a semiconductor device using such an insulating substrate and a method for manufacturing the insulating substrate capable of obtaining such an insulating substrate.

  An insulating substrate according to the present invention includes a base plate that is partitioned on different planes and has a plurality of mounting regions for mounting electronic components, and an insulating layer that is formed on the plurality of mounting regions of the base plate, And a wiring layer formed on the surface of the insulating layer corresponding to a plurality of mounting regions of the base plate.

The base plate preferably has a heat sink on the side opposite to the surface on which the insulating layer is formed. Or it is preferable that a heat sink member is arrange | positioned on the surface on the opposite side to the insulating layer of a base board.
The insulating layer can be formed by any one of thermal spraying, sputtering, chemical vapor deposition, and physical vapor deposition.
Similarly, the wiring layer can be formed by any one of thermal spraying, sputtering, chemical vapor deposition, and physical vapor deposition.
Note that a ceramic insulating layer is preferably used as the insulating layer.

  A semiconductor device according to the present invention includes the above-described insulating substrate, and a plurality of semiconductor elements mounted as electronic components on the surface of the wiring layer corresponding to the plurality of mounting regions of the base plate in the insulating substrate. is there.

The method for manufacturing an insulating substrate according to the present invention provides a base plate that is partitioned on different planes and has a plurality of mounting regions for mounting electronic components, and an insulating layer is formed on the plurality of mounting regions of the base plate. And a wiring layer is formed on the surface of the insulating layer corresponding to a plurality of mounting regions of the base plate.
Here, by spraying over a plurality of mounting areas of the base plate, a common insulating layer is formed in these mounting areas, and a plurality of mountings of the base plate are performed by spraying using a mask on the surface of the insulating layer. Each wiring layer corresponding to the region can be formed.

  According to the present invention, it is possible to realize an insulating substrate capable of mounting a large number of electronic components while being small.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 shows a cross-sectional view of an insulating substrate according to Embodiment 1 of the present invention. This insulating substrate has a base plate 1 made of Al, and this base plate 1 has a three-dimensional structure with a U-shaped cross section composed of three flat plate portions 2 bent substantially at right angles to each other. Here, mounting areas for mounting electronic components are defined on the surfaces of the three flat plate portions 2 constituting the inner surface of the base plate 1 having a U-shaped cross section. An insulating layer 3 made of Al ₂ O ₃ as a ceramic insulating layer is formed on the inner surface of the base plate 1 so as to cover the entire mounting region of the three flat plate portions 2. Further, a wiring layer 4 made of Cu is formed on the surface of the insulating layer 3 so as to correspond to the mounting region of each flat plate portion 2.
The insulating substrate having such a configuration can be used as a semiconductor device by bonding a semiconductor element 5 as an electronic component to the surface of each wiring layer 4 via solder (not shown). Here, one or a plurality of semiconductor elements 5 can be arranged for one mounting region.

Next, a method for manufacturing the insulating substrate according to the first embodiment will be described. First, an Al extruded material formed in a three-dimensional shape having three flat plate portions 2 bent substantially at right angles to each other is prepared as a base plate 1. Next, by spraying the entire surface of the three flat plate portions 2 of the base plate 1, the common insulating layer 3 made of Al ₂ O _{3 is} formed on the _three flat plate portions 2. Further, the wiring layer 4 made of Cu is formed on the surface of the insulating layer 3 by using a mask to form a film corresponding to the mounting area of each flat plate portion 2.
In this way, an insulating substrate is manufactured.

  In this insulating substrate, mounting areas are defined on the surfaces of the three flat plate portions 2 of the base plate 1 that are bent with respect to each other, and electronic components such as the semiconductor element 5 can be disposed on these three mounting areas. Therefore, it is possible to realize an insulating substrate that can be mounted with a large number of electronic components while being small.

Moreover, in order to form the insulating layer 3 and the wiring layer 4 on the surface of each flat plate portion 2 of the base plate 1 having a three-dimensional structure by a thermal spraying method, the insulating layer 3 and the wiring layer 4 are sintered or brazed. It is possible to form a film easily without performing it.
Further, by performing thermal spraying using a mask, the wiring layer 4 having a predetermined pattern corresponding to the mounting region of each flat plate portion 2 can be formed even on the three-dimensional base plate 1.

In addition, the insulating layer 3 and the wiring layer 4 can be easily formed in desired thicknesses by the thermal spraying method, and the thickness can be easily adjusted.
Furthermore, since the base plate 1 has a three-dimensional structure, it is possible to suppress deformation of the base plate 1 due to heat input during thermal spraying and soldering of electronic components, thereby preventing the deformation due to heat input. A substrate is obtained.

Further, by using an Al extruded material as the base plate 1, the base plate 1 can be mass-produced at a low cost.
Further, if the insulating layer 3 is formed from Al ₂ O ₃ as described above, since Al ₂ O ₃ has excellent adhesion with Al, the adhesion between the insulating layer 3 and the base plate 1 is improved.
Furthermore, since the base plate 1 is made of Al having excellent thermal conductivity, the heat generated in the electronic components such as the semiconductor element 5 passes through the wiring layer 4 and the insulating layer 3 and each flat plate portion 2 of the base plate 1. Efficiently dissipated from the outside. Further, the heat generated from the semiconductor element 5 is transmitted in the thickness direction while diffusing in the plane direction of the base plate 1. Therefore, in a base plate having only one normal flat plate portion, heat from adjacent semiconductor elements 5 interfere with each other, and local heat concentration occurs. However, the base plate 1 has a three-dimensional structure. Specifically, the base plate 1 has a three-dimensional structure having a U-shaped cross section composed of three flat plate portions 2 bent substantially at right angles to each other. Therefore, the heat generated from the semiconductor elements 5 and the like on each flat plate portion is less likely to interfere with each other when conducting through the base plate 1, and local heat concentration is suppressed.

Embodiment 2. FIG.
With reference to FIG. 2, an insulating substrate according to the second embodiment will be described. The second embodiment uses a base plate 12 having a heat sink portion 11 outside the U-shaped cross section in place of the base plate 1 in the insulating substrate of the first embodiment. Here, the base plate 12 having a U-shaped cross section has a heat sink portion 11 composed of a plurality of fins 11a on the outer side, that is, on the side opposite to the surface on which the insulating layer 3 is formed. Can be formed from Note that the insulating layer 3 and the wiring layer 4 are laminated on the inner surface of the base plate 12 as in the case of the base plate 1 in the first embodiment, and an electron such as the semiconductor element 5 is formed on the surface of each wiring layer 4. A semiconductor device can be configured by mounting components.

  The base plate 12 is not only made of Al having an excellent thermal conductivity, but also has a heat sink portion 11 on the side opposite to the surface on which the insulating layer 3 is formed. The heat is more efficiently dissipated through the wiring layer 4 and the insulating layer 3 from the heat sink portion 11 of the base plate 12 to the outside.

  As described above, instead of the base plate 12 having the air-cooled heat sink portion 11 formed with the plurality of fins 11a, as shown in FIG. 3, the water-cooled type formed with the plurality of water pipes 13a. A base plate 14 having a heat sink portion 13 can also be used.

Embodiment 3 FIG.
With reference to FIG. 4, an insulating substrate according to the third embodiment will be described. The third embodiment includes a base plate 21 having a U-shaped cross section made of an Al / SiC composite instead of the base plate 1 made of Al in the first embodiment. A heat sink member 22 made of Al or the like is disposed in contact with the surface of the plate 21 opposite to the insulating layer 3. The heat sink member 22 has a plurality of fins 22a formed facing outward.

Here, a semiconductor material such as Si used for an electronic component such as the semiconductor element 5 has a low expansion, but the base plate 21 is formed of an Al / SiC composite material having a small thermal expansion coefficient. The difference in thermal expansion coefficient between the electronic component such as the semiconductor element 5 and the like mounted on the surface of the layer 4 and the base 21 is reduced, the thermal stress generated between them is reduced, the warpage of the electronic component due to the thermal stress, Occurrence of cracks or the like of solder that joins electronic components can be suppressed.
In addition, the Al / SiC composite material constituting the base plate 21 has excellent heat conductivity similar to Al, and the heat sink member 22 made of Al is disposed in contact with the outer surface of the base plate 21. The heat generated by the electronic components such as 5 is efficiently dissipated from the heat sink member 22 to the outside through the wiring layer 4, the insulating layer 3 and the base plate 21.

  Instead of the air-cooled heat sink member 22 having a plurality of fins 22a as described above, as shown in FIG. It can also be disposed in contact with the outer surface of the U-shaped base plate 21, that is, the surface opposite to the surface on which the insulating layer 3 of the base plate 21 is formed.

Embodiment 4 FIG.
A semiconductor device according to the fourth embodiment will be described with reference to FIG. In the fourth embodiment, a pair of semiconductor devices is prepared by mounting electronic components such as the semiconductor element 5 on the insulating substrate of the first embodiment, and the inner surfaces of the pair of semiconductor devices are opposed to each other. The base plate 1 is arranged in contact with the upper end surface.
If comprised in this way, since the semiconductor element 5 mounted in the surface of each wiring layer 4 will be in the state enclosed by the pair of base board 1 which consists of Al, the shielding property with respect to the electric field noise from the outside improves To do.

In addition, as shown in FIG. 3, the heat dissipation can be improved by configuring the semiconductor device as shown in FIG. 7 using the insulating substrate in which the base plate 14 has the water-cooled heat sink portion 13. Similarly, as shown in FIG. 2, the heat dissipation can be improved by forming the semiconductor device using an insulating substrate in which the base plate 12 has the air-cooled heat sink portion 11.
Further, as shown in FIG. 5, as shown in FIG. 8, using an insulating substrate in which a water-cooled heat sink portion 23 is disposed in contact with the outer surface of the base plate 21 having a U-shaped cross section made of an Al / SiC composite material. By configuring a simple semiconductor device, heat dissipation can be improved. Similarly, as shown in FIG. 4, a semiconductor device is configured using an insulating substrate having an air-cooled heat sink portion 22 in contact with the outer surface of a U-shaped base plate 21 to improve heat dissipation. You can also.

Embodiment 5. FIG.
With reference to FIG. 9, the insulating substrate of Embodiment 5 is demonstrated. In the fifth embodiment, an insulating layer 31 and a wiring layer 32 are laminated on the outer surface of the base plate 1 having a U-shaped cross section in the first embodiment instead of the inner surface.

Here, mounting areas for mounting electronic components are defined on the surfaces of the three flat plate portions 2 constituting the outer surface of the base plate 1 having a U-shaped cross section. Further, as in the first embodiment, an insulating layer 31 made of Al ₂ O ₃ is formed on the outer surface of the base plate 1 so as to cover the entire mounting region of the three flat plate portions 2 by a thermal spraying method, A wiring layer 32 made of Cu is formed on the surface of the insulating layer 31 corresponding to the mounting region of each flat plate portion 2 by spraying.
Even with this insulating substrate, an electronic component such as the semiconductor element 5 can be mounted on the surface of each wiring layer 32 to constitute a semiconductor device.

  Since mounting areas are defined on the surfaces of the three flat plate portions 2 constituting the outer surface of the base plate 1 having a U-shaped cross section, and electronic components such as the semiconductor element 5 can be arranged on these three mounting areas, respectively. As in the first embodiment described above, it is possible to realize an insulating substrate that can be mounted with a large number of electronic components while being small.

  In addition, if the base plate 34 which has the heat sink part 33 in which the some water flow pipe 33a was formed as shown in FIG. 10 instead of the base plate 1 is used, heat dissipation can be improved.

Embodiment 6 FIG.
As shown in FIG. 11, the insulating layer 3 and the wiring layer 4 are sequentially laminated on the inner surface of the base plate 1 having a U-shaped cross section, and the insulating layer 31 and the wiring layer 32 are sequentially laminated on the outer surface. The semiconductor device can be configured by mounting electronic components such as the semiconductor element 5 on the surfaces of the inner wiring layers 4 and the outer wiring layers 32 of the base plate 1.

In the above-described first to sixth embodiments, the base plates 1, 12, 14, 21, and 34 can be formed of various materials in addition to Al or Al / SiC composite material, and in particular, Cu, Fe, etc. It is preferable to form it from a material having high heat dissipation. Moreover, you may form from the metal etc. which are easy to extrude or breath-process like Al.
Further, in place of the base plates 1, 12, 14, 21, 34 having a U-shaped cross section, three-dimensional base plates having various cross-sectional shapes such as an L-shaped cross section can be used.

  In the first to sixth embodiments described above, the base plates 1, 12, 14, 21, and 34 are formed in the U-shaped steel mold, but these base plates 1, 12, 14, 21, and 34 are formed. Can be formed in a casing shape. With this configuration, the mounting area for mounting electronic components is increased, and the casing-like base plates 1, 12, 14, 21, and 34 are insulated. When the substrates are opposed to each other as shown in FIGS. 7 and 8, the inside is sealed and the shielding performance is further improved.

In the first to sixth embodiments, the insulating layers 3 and 31 can be formed by a thermal spraying method such as atmospheric pressure plasma spraying (APS) or hot rod flame spraying (locide). Further, an aerosol deposition method and a reduced pressure plasma method may be used. In this case, a dense structure can be formed as compared with atmospheric pressure plasma spraying or rod-type flame spraying, and high thermal conductivity can be expected.
Moreover, in the above-mentioned embodiment, although the base plate was produced by the extrusion process, you may produce it by press work, casting, die casting, etc.
The insulating layers 3 and 31 are not limited to Al ₂ O ₃ , and can be formed from various materials having insulating properties and capable of thermal spraying. Moreover, high thermal conductivity and low expansion can be expected by using a ceramic insulating layer as the insulating layer.

The wiring layers 4 and 32 can be formed by a thermal spraying method such as high-speed flame spraying (HVOF) or cold spray.
Further, the wiring layers 4 and 32 are not limited to Cu, and can be formed from various materials having conductivity and capable of thermal spraying.

Here, Cu layers were formed by the cold spray method and the atmospheric pressure plasma spraying method, respectively, and the cross-sectional structure thereof was observed. In the Cu layer formed by the cold spray method, almost no oxidation of metal particles was observed. The porosity was about 1%, whereas in the Cu layer formed by atmospheric pressure plasma spraying, the surface layer of metal particles was oxidized, and a porosity of about 10% was confirmed. Further, the residual stress of the Cu layer was a compressive force when the film was formed by the cold spray method, and a tensile force when the film was formed by the atmospheric pressure plasma spraying method.
In addition to the thermal spraying method, the insulating layer and the wiring layer may be formed by sputtering, chemical vapor deposition, or physical vapor deposition.

It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on Embodiment 1 of this invention. It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on Embodiment 2 of this invention. It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on the modification of Embodiment 2 of this invention. It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on Embodiment 3 of this invention. It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on the modification of Embodiment 3 of this invention. It is sectional drawing which shows the semiconductor device which concerns on Embodiment 4 of this invention. It is sectional drawing which shows the semiconductor device which concerns on the modification of Embodiment 4 of this invention. It is sectional drawing which shows the semiconductor device which concerns on another modification of Embodiment 4 of this invention. It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on Embodiment 5 of this invention. It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on the modification of Embodiment 5 of this invention. It is sectional drawing which shows a mode that the semiconductor element was mounted in the insulated substrate which concerns on Embodiment 6 of this invention.

Explanation of symbols

  1, 12, 14, 21, 34 Base plate, 2 flat plate portion, 3, 31 insulating layer, 4, 32 wiring layer, 5 semiconductor element, 11, 13 heat sink portion, 11a, 22a fin, 13a, 23a water pipe, 22 , 23 Heat sink member.

Claims (11)

A base plate which is partitioned on different planes and has a plurality of mounting areas for mounting electronic components,
An insulating layer formed on a plurality of mounting regions of the base plate;
An insulating substrate comprising: a wiring layer formed on the surface of the insulating layer corresponding to a plurality of mounting regions of the base plate.   The insulating substrate according to claim 1, wherein the base plate has a heat sink portion on a side opposite to a surface on which the insulating layer is formed.   The insulating substrate according to claim 1, further comprising a heat sink member disposed on a surface of the base plate opposite to the insulating layer.   The insulating substrate according to claim 1, wherein the insulating layer is formed by a thermal spraying method.   The insulating substrate according to any one of claims 1 to 3, wherein the insulating layer is formed by sputtering, chemical vapor deposition, or physical vapor deposition.   The insulating substrate according to claim 1, wherein the wiring layer is formed by a thermal spraying method.   The insulating substrate according to claim 1, wherein the wiring layer is formed by sputtering, chemical vapor deposition, or physical vapor deposition.   The insulating substrate according to claim 1, wherein the insulating layer is a ceramic insulating layer. An insulating substrate according to any one of claims 1 to 8,
A semiconductor device comprising: a plurality of semiconductor elements each mounted as an electronic component on the surface of the wiring layer corresponding to a plurality of mounting regions of the base plate on the insulating substrate. Preparing a base plate which is partitioned on different planes and has a plurality of mounting areas for mounting electronic components,
Forming an insulating layer on a plurality of mounting regions of the base plate;
A method for producing an insulating substrate, comprising forming a wiring layer on the surface of the insulating layer corresponding to a plurality of mounting regions of the base plate. Forming the insulating layer common to the plurality of mounting regions by spraying over the plurality of mounting regions of the base plate;
The method for manufacturing an insulating substrate according to claim 10, wherein the wiring layers corresponding to a plurality of mounting regions of the base plate are formed by thermal spraying on the surface of the insulating layer using a mask.

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