JPH11220226A - Hybrid module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hybrid module, which is small-sized and has good heat dissipation property. SOLUTION: A hybrid module 10 is constituted into such a structure that a circuit board 11 is constituted of a multilayered board formed by laminating ceramic sheets, and at the same time by using a sheet having an open part, when the board 11 is mounted on a mother circuit board, a recess 14 is formed in the main surface, which faces opposite to the mother circuit board of the board 11, and when a circuit component 13 having heat generating property is mounted in the recess 14 and the board 11 is mounted on the mother circuit board, the component 13 makes direct contact the mother circuit board or contact the mother circuit board via a radiating member, and the heat generated from the component 13 is conducted to the mother circuit board and is dissipated. Thereby, the module 10 is formed into a small size and can perform efficiently heat dissipation, and at the same time, the density of the board 11 can be almost evenly set extending over the whole region and the module can be provided with the board 11, in which warpages will not be generated, is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid module in which chip components such as multilayer capacitors and multilayer inductors and semiconductor components are mounted on a circuit board on which a circuit pattern is formed to form a circuit. The present invention relates to a hybrid module mounted with a heat-generating circuit component such as a field-effect transistor or a power semiconductor.

[0002]

2. Description of the Related Art Conventionally, in a hybrid module in which a heat-generating circuit component such as a field-effect transistor or a power semiconductor is mounted on a circuit board, a special heat radiating means is provided in order to radiate heat from the circuit component. is there. For example, in a hybrid module disclosed in Japanese Patent Application Laid-Open No. Hei 5-13627, a heat radiation fin 22 is provided on a circuit board 21 and a heat-generating circuit component 23 mounted on the circuit board 21 is mounted as shown in FIG. , Leaf spring-shaped heat conducting member 2
4 are connected to the heat radiation fins 22. In this hybrid module 20, the heat generated by the circuit components 23 is released to the atmosphere via the heat radiation fins 22.

FIG. 3 shows another conventional hybrid module having a circuit board having heat-generating circuit components mounted thereon. In this hybrid module 20 ′, an aluminum nitride ceramic is used as the circuit board 25, the chip-shaped electronic component 27 is mounted on the land electrode 26 on the circuit board 25, and the solder bumps 28 are mounted on the land electrode 26. A circuit component 29 such as a semiconductor element having a heat generating property is mounted via the device.

The circuit board 25 is mounted on the parent circuit board 30, and the terminal electrodes 25a of the circuit board 25 are
It is connected to a land electrode 31 formed on the parent circuit board 30 by solder.

[0005] Further, the opposing surfaces of the circuit board 25 and the parent circuit board 30 are joined via a conductor film 32 having good thermal conductivity formed on the parent circuit board 30.

[0006] Aluminum nitride-based ceramics have attracted attention as insulating materials having good thermal conductivity. In the above-described hybrid module, heat generated from the circuit components 29 mounted on the circuit board 25 is transferred to the parent circuit board 30 via the circuit board 25 made of aluminum nitride ceramic and having good thermal conductivity and the conductor film 32. Conducted and dissipated.

[0007]

However, the former hybrid module 20 in the above-mentioned conventional example is required.
Is for releasing the heat generated in the circuit component 23 to the atmosphere via the radiating fins 22. In order to enhance the heat radiation efficiency, it is necessary to increase the surface area of the radiating fins 22 inevitably. For this reason, there is a problem that the volume occupied by the radiation fins 22 in the hybrid module 20 is large, and it is difficult to reduce the size.

Further, in the latter hybrid module 20 'in the above-described conventional example, since the heat generated in the circuit components 29 is radiated to the parent circuit board 30 via the circuit board 25, no radiating fin is required. Since the circuit board 25 also serves as a heat radiating means, there is no increase in volume.Although aluminum nitride-based ceramics have good thermal conductivity, they are extremely expensive at present compared to general board materials such as alumina. There was a problem that the cost was increased.

An object of the present invention is to provide a compact hybrid module with good heat dissipation in view of the above problems.

[0010]

In order to achieve the above object, according to the present invention, there is provided a circuit board comprising: a circuit board; and a heat-generating circuit component mounted on the circuit board. In the hybrid module mounted and used on the above, the circuit board is formed of a multi-layer board in which a plurality of sheets of a predetermined thickness are stacked, and a sheet having an opening is stacked on a main surface facing the parent circuit board. The present invention proposes a hybrid module in which the concave portion is formed, the circuit component is mounted in the concave portion, and heat conduction is performed from the circuit component to the parent circuit board.

According to the hybrid module, the circuit board is constituted by a multilayer board, and when the circuit board is mounted on the master circuit board, a recess is formed on the main surface facing the master circuit board, and the inside of the recess is formed. The circuit components are mounted on. Thereby, when the circuit board is mounted on the parent circuit board,
The circuit component is in direct contact with the parent circuit board or via a heat radiating member, and the heat generated from the circuit component is conducted to the parent circuit board and radiated. Heat can be dissipated well.

According to a second aspect, in the hybrid module according to the first aspect, the density of the circuit board is:
We propose a hybrid module that is set almost uniformly over the entire circuit board.

According to the hybrid module, since the density of the circuit board is set substantially uniformly over the entire circuit board, the occurrence of warpage of the circuit board due to a change in ambient temperature or humidity is prevented.

According to a third aspect of the present invention, there is provided the hybrid module according to the first or second aspect, wherein the internal electrode and the surface electrode formed on the circuit board are made of silver or copper.

According to the hybrid module, since the internal electrodes and the surface electrodes constituting the circuit patterns, through holes, land electrodes, terminal electrodes and the like are made of silver or copper,
Excellent heat dissipation and high frequency characteristics are obtained.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing a hybrid module according to one embodiment of the present invention. In the figure, reference numeral 10 denotes a hybrid module, and a plurality of chip-shaped electronic components 1 are mounted on a circuit board 11 on which a circuit pattern is formed.
2, and a circuit component 13 such as a semiconductor element having heat generation is mounted.

The circuit board 11 is made of a rectangular parallelepiped ceramic multilayer board mainly composed of alumina, and has a bottom surface, that is, a main surface 11a facing the parent circuit board when mounted on the parent circuit board 30, and a heat-generating circuit. A concave portion 14 for mounting the component 13 is formed.

The recess 14 is formed in two stages,
A first recess 14A is formed on the side a, and a slightly smaller second recess 14B is formed in the first recess 14A.

The second concave portion 14B is formed to be slightly larger than the vertical and horizontal thickness dimensions in accordance with the shape of the circuit component 13 mounted therein. Further, the second concave portion 14B
A land electrode 15 for connecting the terminal electrode of the circuit component 13 is formed on the bottom surface of the substrate.

In the second recess 14B, a circuit component 13 such as a semiconductor element and an FET having heat generation is housed, and the terminal electrode of the circuit component 13 is connected to a land electrode 15 formed on the bottom surface of the recess 14B. The adjacent land electrodes 15 are connected and filled with an insulating sealing resin. In this state, the back surface of the circuit component 13 is substantially the same as the bottom surface of the first recess 14A.

Here, the connection between the terminal electrode of the circuit component 13 and the land electrode 15 may be performed by soldering, connection using a conductive resin, connection using an anisotropic conductive resin (ACF),
Alternatively, it is performed by forming a ball bump using gold (Au) on the land electrode 15 and performing thermocompression bonding with ultrasonic wave.

The connection using the above-mentioned conductive resin is inexpensive, has the effect of being able to absorb stress by the conductive resin, and has the effect of obtaining high reliability. It does not adversely affect the heat radiation effect. Further, if an anisotropic conductive resin is used, a sealing resin for insulating the land electrodes 15 from each other becomes unnecessary, and cost can be reduced.

Further, according to the method of forming a ball bump on the land electrode 15 and thermocompression combined with ultrasonic waves, since the process is a dry process, damage to the circuit component 13 by the plating solution is small, and the equipment cost can be reduced. In addition, the work time for mounting the circuit component 13 on the circuit board 11 can be reduced,
The mounting cost can be reduced. Furthermore, since it is an Au-Au junction, contact resistance is small and high reliability can be obtained.

In the method using solder, the position is corrected by self-alignment, so that mounting accuracy is not required. In addition, since mounting can be performed with a low load at the time of mounting, damage to the circuit component 13 is small, and furthermore, High reliability can be obtained because stress can be absorbed by the solder bumps.

On the other hand, a heat sink 16 having a size to be fitted into the first recess 14A is mounted in the first recess 14A, and the heat sink 16 and the bottom side surface of the first recess 14A and the circuit component 13 are provided.
Is bonded by a heat conductive resin 17, and the concave portion 14 is sealed by a heat radiating plate 16. In this state, the surface of the heat sink 16 is substantially the same as the main surface 11a of the circuit board 11.

A land electrode 15 is formed on a surface facing the main surface 11a of the circuit board 11, that is, on the upper surface of the circuit board 11 in the drawing, and the chip-shaped electronic component 12 is soldered to the land electrode 15. The chip-shaped electronic component 12 is a metal case 18 fitted on the upper surface of the circuit board 11.
Covered by Further, a plurality of terminal electrodes 19 connected to the circuit pattern are formed on the side surface of the circuit board 11.

On the other hand, as described above, the circuit board 11 has a multilayer structure, in which a circuit pattern is formed, and each land electrode 15 is connected to this circuit pattern. This effectively utilizes the volume of the circuit board,
The module is being miniaturized.

Here, as shown in FIG. 4, the circuit board 11 is formed by laminating and compressing ceramic green sheets (hereinafter referred to as green sheets) 101 to 107 mainly composed of alumina, followed by firing. You.

Each of the green sheets 101 to 107
Although not shown, through holes are formed and internal electrodes such as circuit conductor patterns and land electrodes and surface electrodes are printed and formed using silver (Ag) or copper (Cu). By using silver or copper for the electrodes as described above, heat dissipation and high-frequency characteristics can be improved.

An opening 108a having a shape corresponding to the first concave portion 14A is formed at a predetermined position in the lowermost green sheet 107, and two green sheets 105, 106 laminated on the green sheet 107 are further formed. Have openings 10 each having a shape corresponding to the second recess 14B.
5a and 106a are formed at predetermined positions.

As described above, the circuit board 11 is a multilayer board formed by laminating a plurality of green sheets 101 to 107, and the green sheets 105 to 107 having openings 105a, 106a, and 107a are further laminated to form the recess 14 Is formed, the density can be set uniformly over the entire area of the circuit board 11. For example, when green sheets having no opening are laminated and the recess 14 is formed by press working or the like, the density of the circuit board is partially different inside the circuit board, and the circuit board is changed due to a change in ambient temperature or humidity. Of the circuit component 13 and the cutability of the circuit pattern occurs, and the mountability of the circuit component 13 is extremely deteriorated.

As described above, by forming the circuit board 11 from a multilayer board in which green sheets having openings are laminated, the circuit board 11 having the concave portions 14 and having no warp can be easily manufactured.

When pressing the green sheets 101 to 107 after laminating them, as shown in FIG.
Is used. This allows
The surface roughness of the inner surface of the concave portion 14 of the circuit board 11 can be reduced to about 10 μ or less, and the formation of the land electrode 15 and the bump inside the concave portion 14 can be easily performed.

On the other hand, when the hybrid module 10 having the above-described configuration is mounted on the parent circuit board, as shown in FIG. 6, the concave portion 14 of the circuit board 11 on which the circuit components 13 are mounted faces downward. The main surface 11a is mounted to face the parent circuit board 30, and the terminal electrodes 19 on the side surfaces of the circuit board 11 are mounted.
Is soldered to the land electrode 31 of the parent circuit board 30.

On the surface of the mother circuit board 30, a heat conductive conductor film 32 (eg, a ground pattern) is formed in advance together with the land electrode 31 at a position facing the heat radiating plate 16 of the hybrid module 10. At the same time that the terminal electrodes 19 of the circuit board 11 are soldered to the land electrodes 31, the surface of the heat sink 16 is soldered to the conductor film 32.

The heat radiating plate 16 and the conductive film 32 need not be soldered, but may be simply brought into contact with each other, or may be brought into contact with each other via a heat conductive resin. The heat sink 16 may directly contact the surface of the parent circuit board 30.

In this hybrid module, heat generated from the circuit component 13 such as a semiconductor element having heat generation is transmitted to the parent circuit board 30 via the heat radiating plate 16, the heat conductive resin 17 and the conductive film 32, or the ground or the like. Conducted by the wide conductor film and dissipated.

Therefore, it is possible to manufacture a hybrid module which is small in size and can efficiently dissipate heat at a low cost.

In the above-described embodiment, the heat generated from the circuit components 13 via the heat radiating plate 16 is not changed.
However, as in the hybrid module 50 shown in FIG.
The back surface of 3 may be directly in contact with the conductor film 32 or may be soldered.

The circuit component 13 is made of GaAsM
ES type FET, GaAs PHEMT type FET, or I
It is desirable to use an nP-based FET.

That is, GaAs MES is used as the circuit component 13.
When the type FET is used, heat generation from the element is small because electrons move quickly inside the element, the linear expansion coefficient of GaAs is 6 ppm / ° C., which is larger than that of silicon (Si), and the circuit board 11, the heat radiating plate 16, In addition, since the coefficient of thermal expansion is close to the linear expansion coefficient of the heat conductive resin 17 and the like, the stress generated by the temperature change is reduced, and high reliability can be obtained.

Further, GaAsPHE is used as the circuit component 13.
When the MT-type FET is used, since the electron movement speed inside the element is faster than that of the MES-type FET, heat generation from the element can be further reduced, and the linear expansion coefficient is also larger than that of silicon (Si). , Circuit board 11, heat sink 1
6, and the coefficient of thermal expansion of the thermal conductive resin 17 and the like are close to each other, so that the stress generated by the temperature change is small, and high reliability can be obtained.

Further, as the circuit component 13, an InP-based FE
When T is used, the moving speed of electrons inside the device is G
Since it is faster than aAs, the heat generation from the element can be further reduced, and the linear expansion coefficient is 5 ppm / ° C., which is larger than that of silicon (Si). Since the coefficient is close to the coefficient, the stress generated by the temperature change is reduced, and high reliability can be obtained.

Further, it is preferable to use SiN or SiO ₂ or a composite film thereof for insulation (passivation) between the terminal electrodes of the circuit component 13. By using these, even if the moisture resistance of the sealing resin is insufficient, the characteristics of the element are not degraded, and the reliability of the element is improved even if a void is generated in the sealing resin and moisture enters. Do not deteriorate. Furthermore, since the reliability of the element is not deteriorated even if the residual ions of the sealing resin are large, an inexpensive sealing resin can be used.

Further, in the above embodiment, the module in which one heat-generating circuit component 13 is mounted is configured, but a module in which a plurality of heat-generating circuit components are mounted may be used.
In this case, the same effect can be obtained.

When a plurality of heat-generating FETs are used, it is preferable to use a circuit component 13 in which the plurality of FETs are formed on one GaAs. This allows
The mounting area can be reduced as compared with the case where a plurality of FETs are individually mounted, and the mounting cost can be reduced since only one mounting operation is required. Furthermore, compared to the case where a plurality of FETs are individually mounted, the heat sink 16 or the parent circuit board 3
0 can be easily contacted, and heat radiation can be stabilized.

[0047]

As described above, according to the hybrid module of the first aspect of the present invention, the circuit board is a multilayer board, and the circuit components are mounted in the recesses formed on the main surface facing the parent circuit board. When the circuit board is mounted on the parent circuit board, the circuit component is in direct contact with the parent circuit board or via a heat radiating member, and the heat generated from the circuit component is conducted to the parent circuit board to radiate heat. Therefore, it is possible to reduce the size and achieve high-density mounting, and efficiently radiate heat.

According to the second aspect of the present invention, in addition to the above effects, the density of the circuit board is set to be substantially uniform over the entire circuit board, so that the warpage of the circuit board due to a change in ambient temperature or humidity can be prevented. Since the occurrence is prevented, the cutting of the circuit pattern caused by the warpage of the circuit board can be prevented, and the mountability of the circuit component on the circuit board can be improved.

According to the third aspect, in addition to the above effects, since the internal electrode and the surface electrode are made of silver or copper,
Excellent heat dissipation and high frequency characteristics are obtained.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a hybrid module according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing a conventional hybrid module.

FIG. 3 is a side sectional view showing another conventional hybrid module.

FIG. 4 is a diagram illustrating a configuration of a circuit board according to an embodiment of the present invention.

FIG. 5 is a view for explaining a method for crimping a laminated sheet according to an embodiment of the present invention.

FIG. 6 is a diagram showing an example of mounting a parent circuit board on a hybrid module according to an embodiment of the present invention.

FIG. 7 is a side sectional view showing another embodiment of the hybrid module of the present invention.

[Explanation of symbols]

10, 50: hybrid module, 11: circuit board, 11a: main surface, 12: chip-like electronic component, 13: heat-generating circuit component, 14: concave portion, 14A: first concave portion, 1
4B: second concave portion, 15: land electrode, 16: heat sink,
17: heat conductive resin, 18: metal case, 19: terminal electrode, 30: parent circuit board, 31: land electrode, 32: heat conductive conductor film, 40: press machine, 101 to 107: ceramic green sheet, 105a, 106a, 107a
…Aperture.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kazuki Yagi Taiyo Electric Co., Ltd. 6-16-20 Ueno, Taito-ku, Tokyo

Claims (3)

[Claims] 1. A hybrid module comprising: a circuit board; and a circuit component having heat generation mounted on the circuit board and used by being mounted on a parent circuit board. The concave portion is formed on a main surface facing the parent circuit board by laminating sheets having openings, and the circuit component is mounted in the concave portion. Characterized in that the module is thermally conducted to the parent circuit board from the substrate. 2. The hybrid module according to claim 1, wherein the density of the circuit board is set substantially uniformly over the entire circuit board. 3. The hybrid module according to claim 1, wherein the internal electrode and the surface electrode formed on the circuit board are made of silver or copper.