阅读说明：本技术 半导体装置 (Semiconductor device with a plurality of semiconductor chips ) 是由 佐藤正基 白形雄二 铃木规央 村田信二 于 2018-11-27 设计创作，主要内容包括：目的在于提供对框体内的半导体模块以及电子部件进行冷却的半导体装置。半导体装置具备：散热器,包括翅片和板状的基部,在基部的一个面设置有半导体模块,在另一个面设置有翅片；框体,覆盖基部的一个面、半导体模块、电子部件以及电路基板而安装于基部,在与一个面之间收容半导体模块；风扇,冷却翅片；以及第1通气口和第2通气口,分别连通框体内外。第1通气口与电子部件距电路基板的高度为最高的部分的一半的高度相比设置于上部,所述电子部件安装于框体内的电路基板的一面。第2通气口贯通框体内的基部的一个面和另一个面。第1通气口和第2通气口在框体内形成风路。电路基板的一面处的冷却风的风速比电子部件上的冷却风的风速小。(The purpose is to provide a semiconductor device for cooling a semiconductor module and an electronic component in a housing. The semiconductor device includes: a heat sink including fins and a plate-like base portion, the base portion having a semiconductor module provided on one surface thereof and fins provided on the other surface thereof; a frame body which is mounted on the base portion so as to cover the one surface of the base portion, the semiconductor module, the electronic component, and the circuit board, and accommodates the semiconductor module between the frame body and the one surface; a fan to cool the fins; and a 1 st vent hole and a 2 nd vent hole which communicate the inside and outside of the frame body, respectively. The 1 st vent is provided at an upper portion of the circuit board at a height half of a portion where the height of the electronic component from the circuit board is highest, and the electronic component is mounted on one surface of the circuit board in the housing. The 2 nd vent hole penetrates one surface and the other surface of the base part in the frame body. The 1 st air vent and the 2 nd air vent form an air passage in the housing. The speed of the cooling air on one surface of the circuit board is lower than the speed of the cooling air on the electronic component.)

1. A semiconductor device includes:

a heat sink including a fin forming a 1 st air passage through which a 1 st cooling air flows from one end to the other end, and a base having a plate-like shape, the base having a semiconductor module provided on one surface thereof and the fin standing on the other surface thereof;

a frame body mounted on the base portion of the heat sink so as to cover the one surface of the base portion, the semiconductor module, an electronic component operating in association with the semiconductor module, and a circuit board on which the electronic component is mounted, the frame body housing the semiconductor module in a space formed between the frame body and the one surface;

a fan configured to blow the 1 st cooling air into the 1 st air passage to cool the fins;

a 1 st air vent for communicating the inside of the frame body and the outside of the frame body and taking a 2 nd cooling air into the frame body; and

a 2 nd air vent communicating the inside of the frame body and the outside of the frame body and discharging the 2 nd cooling air taken into the inside of the frame body to the outside of the frame body,

the 1 st vent is provided at an upper portion of the electronic component than a half height of a portion where the height of the electronic component from the circuit board is highest, the electronic component being mounted on one surface of the circuit board in the housing,

the 2 nd vent hole is formed through the one surface and the other surface of the base in the frame,

the 1 st air vent and the 2 nd air vent form a 2 nd air path in the frame body as follows: the 2 nd cooling air is taken in from the 1 st vent and discharged from the 2 nd vent to the outside of the frame body due to a pressure difference between the inside and the outside of the frame body formed at the 2 nd vent due to the flow of the 1 st cooling air.

The speed of the 2 nd cooling wind at the one surface of the circuit board is lower than the speed of the 2 nd cooling wind on the electronic component.

2. The semiconductor device according to claim 1,

the 2 nd vent is provided at an upper portion of the highest electronic component than the half height thereof.

3. The semiconductor device according to claim 1 or 2,

the 1 st air vent is arranged on the frame body,

the base portion includes a notch portion that penetrates the one surface and the other surface at least at a portion of one side forming the plate-like shape,

the one side provided with the notch portion is located on the other end side of the fin,

the No. 2 vent includes at least a portion of the notched portion.

4. The semiconductor device according to claim 1 or 2,

the base includes:

a stepped portion provided on the one surface including at least a part of a 1 st side forming the plate-like shape; and

a notch portion that penetrates the one surface and the other surface at least at a portion of a 2 nd side forming the plate-like shape,

the 1 st edge provided with the stepped portion is located on the one end side of the fin,

the 2 nd side provided with the notch portion is located on the other end side of the fin,

the 1 st vent includes at least a portion of the step,

the No. 2 vent includes at least a portion of the notched portion.

5. The semiconductor device according to any one of claims 1 to 4,

the fan is provided on the one end side of the fin, and sends out wind from the one end side to the other end side, thereby blowing the 1 st cooling wind.

6. The semiconductor device according to claim 5,

the fan is provided such that an upper end portion of the fan is located below a surface defined by the other surface of the base portion.

7. The semiconductor device according to any one of claims 1 to 4,

the fan is provided on the other end side of the fin, and draws wind from the one end side to the other end side, thereby blowing the 1 st cooling wind.

8. The semiconductor device according to any one of claims 1 to 7,

the semiconductor device further includes an electronic component heat sink that is provided in the 2 nd air passage formed in the housing and cools the electronic component.

9. A semiconductor device includes:

a heat sink including a fin forming a 1 st air passage through which a 1 st cooling air flows from one end to the other end, and a base having a plate-like shape, the base having a semiconductor module provided on one surface thereof and the fin standing on the other surface thereof;

a frame body mounted on the base portion of the heat sink so as to cover the one surface of the base portion, the semiconductor module, an electronic component operating in association with the semiconductor module, and a circuit board on which the electronic component is mounted, the frame body housing the semiconductor module in a space formed between the frame body and the one surface;

a fan configured to blow the 1 st cooling air into the 1 st air passage to cool the fins;

a 1 st air vent for communicating the inside of the frame body and the outside of the frame body and taking a 2 nd cooling air into the frame body; and

a 2 nd air vent communicating the inside of the frame body and the outside of the frame body and discharging the 2 nd cooling air taken into the inside of the frame body to the outside of the frame body,

the fan further blows the 2 nd cooling wind to the 1 st air vent,

the 1 st air vent and the 2 nd air vent form a 2 nd air passage in the housing by blowing the 2 nd cooling air to the 1 st air vent by the fan, and in the 2 nd air passage, the 2 nd cooling air is taken in from the 1 st air vent and discharged from the 2 nd air vent to the outside of the housing.

10. The semiconductor device according to claim 9,

the 1 st vent is provided at an upper portion of the electronic component than a half height of a portion where the height of the electronic component from the circuit board is highest, the electronic component being mounted on one surface of the circuit board in the housing,

the speed of the 2 nd cooling wind at the one surface of the circuit board is lower than the speed of the 2 nd cooling wind on the electronic component.

11. The semiconductor device according to claim 10,

the 2 nd vent is provided at an upper portion of the highest electronic component than the half height thereof.

12. The semiconductor device according to any one of claims 9 to 11,

the base includes:

a stepped portion provided on the one surface including at least a part of a 1 st side forming the plate-like shape; and

a notch portion that penetrates the one surface and the other surface at least at a portion of a 2 nd side forming the plate-like shape,

the 1 st edge provided with the stepped portion is located on the one end side of the fin,

the 2 nd side provided with the notch portion is located on the other end side of the fin,

the 1 st vent includes at least a portion of the step,

the No. 2 vent includes at least a portion of the notched portion,

the fan is provided on the one end side of the fin such that an upper end portion of the fan is positioned above a surface defined by a bottom surface of the stepped portion of the base portion.

13. The semiconductor device according to any one of claims 9 to 12,

the semiconductor device further includes an electronic component heat sink that is provided in the 2 nd air passage formed in the housing and cools the electronic component.

Technical Field

The present invention relates to a semiconductor device, and more particularly, to a technique for cooling a heat generating component covered with a housing.

Background

Heat dissipation of a power semiconductor device as a heat generating component is designed by a heat sink, a fan, and the like. For example, the power semiconductor device has a structure in which a heat sink including a base and a fin is screwed to one surface of a power semiconductor element. By ventilating the cooling air generated by the fan or the like to the fins of the heat sink, heat generated by the power semiconductor element is radiated. However, the cooling effect of the component not mounted on the heat sink is smaller than that of the power semiconductor element mounted on the heat sink. Further, these components have a problem of being overheated by receiving heat generated from the power semiconductor element.

Patent document 1 discloses an electronic device provided with a through hole penetrating a base portion on which a heat generating component is mounted. The through-holes eliminate air stagnation caused by the member blocking ventilation, and the cooling effect is improved.

Disclosure of Invention

In the electronic device described in patent document 1, an air passage through which cooling air flows is not formed, and heat generating components other than the heat generating component attached to the base are not cooled.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a semiconductor device in which an air passage is formed in a housing, and which can cool not only a semiconductor module mounted on a heat sink but also electronic components provided in the housing.

The semiconductor device of the present invention includes: a heat sink including fins forming a 1 st air passage through which a 1 st cooling air flows from one end to the other end, and a base having a plate-like shape, the base having a semiconductor module on one surface and fins standing on the other surface; a frame body which is mounted on the base portion of the heat sink so as to cover the one surface of the base portion, the semiconductor module, the electronic component operating in association with the semiconductor module, and the circuit board on which the electronic component is mounted, and which accommodates the semiconductor module in a space formed between the frame body and the one surface; a fan for blowing the 1 st cooling air to the 1 st air passage and cooling the fins; a 1 st air vent which communicates the inside and outside of the frame body and takes the 2 nd cooling air into the frame body; and a 2 nd air vent communicating the inside and outside of the frame body and discharging the 2 nd cooling air taken into the inside of the frame body to the outside of the frame body. The 1 st vent is provided at an upper portion of the circuit board at a height half of a portion where the height of the electronic component from the circuit board is highest, and the electronic component is mounted on one surface of the circuit board in the housing. The 2 nd vent is formed through one surface and the other surface of the base in the frame. The 1 st air vent and the 2 nd air vent form a 2 nd air path in the frame body as follows: due to the pressure difference between the inside and the outside of the frame formed by the 2 nd air vent caused by the flow of the 1 st cooling air, the 2 nd cooling air is taken in from the 1 st air vent and is discharged from the 2 nd air vent to the outside of the frame. The speed of the 2 nd cooling air on one surface of the circuit board is lower than the speed of the 2 nd cooling air on the electronic component.

According to the present invention, it is possible to provide a semiconductor device in which an air passage is formed in a housing, and which can cool not only a semiconductor module mounted on a heat sink but also electronic components provided in the housing.

The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and the accompanying drawings.

Drawings

Fig. 1 is a perspective view showing the structure of a semiconductor device in embodiment 1.

Fig. 2 is a cross-sectional view showing the structure of the semiconductor device in embodiment 1.

Fig. 3 is a perspective view showing a structure of a heat sink included in the semiconductor device in embodiment 1.

Fig. 4 is a diagram showing pressure distributions when air is blown into and out of the semiconductor device in embodiment 1.

Fig. 5 is a diagram showing the flow velocity distribution when air is blown into and out of the semiconductor device in embodiment 1.

Fig. 6 is a diagram showing temperature distributions when air is blown into and out of the semiconductor device in embodiment 1.

Fig. 7 is a cross-sectional view showing the structure of a semiconductor device in modification 1 of embodiment 1.

Fig. 8 is a cross-sectional view showing the structure of a semiconductor device in modification 2 of embodiment 1.

Fig. 9 is a cross-sectional view showing the structure of a semiconductor device in modification 3 of embodiment 1.

Fig. 10 is a perspective view showing the structure of a semiconductor device in modification 4 of embodiment 1.

Fig. 11 is a cross-sectional view showing the structure of a semiconductor device in modification 4 of embodiment 1.

Fig. 12 is a perspective view showing the structure of a semiconductor device in embodiment 2.

Fig. 13 is a perspective view showing the structure of a semiconductor device in embodiment 2.

Fig. 14 is a cross-sectional view showing the structure of a semiconductor device in embodiment 2.

Fig. 15 is a perspective view showing a structure of a heat sink included in the semiconductor device in embodiment 2.

Fig. 16 is a cross-sectional view showing the structure of a semiconductor device in embodiment 3.

Fig. 17 is a cross-sectional view showing the structure of a semiconductor device in embodiment 4.

(description of reference numerals)

1: a circuit substrate; 2: a semiconductor module; 3: a fin; 3 a: one end; 3 b: the other end; 4: a base; 41: the 1 st edge; 42: the 2 nd side; 4 a: a face; 4 b: the other side; 4 c: a notch portion; 4 d: a step portion; 4 e: a bottom surface; 5: a heat sink; 6: a frame body; 7: a fan; 7 a: an upper end portion; 8: the 1 st air vent; 9: a 2 nd vent; 10: an electronic component; 12: a heat sink for electronic components; WP 1: the 1 st air path; WP 2: and 2 nd air path.

Detailed Description

< embodiment 1>

(Structure of semiconductor device)

A semiconductor device in embodiment 1 will be described. Fig. 1 is a perspective view schematically showing the structure of a semiconductor device according to embodiment 1. Fig. 2 is a cross-sectional view schematically showing the structure of the semiconductor device in embodiment 1, and shows a cross-section at a-a' shown in fig. 1. Fig. 3 is a perspective view schematically showing the structure of a heat sink 5 included in the semiconductor device according to embodiment 1. In embodiment 1, one end 3a of the heat sink 5 is a lower side and the other end 3b is an upper side with respect to the mounting direction of the semiconductor device.

As shown in fig. 2, the semiconductor device includes a heat sink 5 to which the semiconductor module 2 is mounted, a frame 6, a fan 7, a 1 st vent 8, and a 2 nd vent 9. The semiconductor device according to embodiment 1 includes the circuit board 1 and the electronic component 10 in addition to the above configuration. The semiconductor module 2 is, for example, a power semiconductor module. The power semiconductor module includes at least 1 semiconductor element (not shown), for example. The semiconductor element is, for example, a power semiconductor element including a wide bandgap semiconductor such as SiC or GaN. The semiconductor device is, for example, a power semiconductor device including a power semiconductor element.

The heat sink 5 includes fins 3 forming a 1 st air path WP1 through which the 1 st cooling air flows from the one end 3a to the other end 3b, and a base 4 having a plate-like shape. The semiconductor module 2 is provided on one surface 4a of the base 4, and the fin 3 is provided upright on the other surface 4 b. As shown in fig. 3, in embodiment 1, a plurality of fins 3 are provided, and the fins 3 are provided in parallel with each other. The base portion 4 is provided with a notch 4c penetrating the first surface 4a and the second surface 4 b. The notch 4c is provided in at least a part of one side of the base 4 forming a plate shape. One side where the notch 4c is provided is located on the other end 3b side of the fin 3. The notch 4c penetrates the base 4 and the fin 3. However, the form of the notch 4c is not limited to this. The notch portion may be configured to penetrate the base portion 4, or may be configured not to penetrate the fin 3. The planar shape of the notch 4c is rectangular, but the notch is not limited to rectangular and may have any shape.

The frame 6 is attached to the base 4 of the heat sink 5 so as to cover the one surface 4a of the base 4, the semiconductor module 2, the electronic component 10, and the circuit board 1. The frame 6 accommodates the semiconductor module 2 in a space formed between the frame and the one surface 4a of the base 4. The electronic component 10 is an electronic component that operates in association with a semiconductor module. The electronic component 10 is mounted on the surface 1a of the circuit board 1. In embodiment 1, the electronic component 10 is also provided on the back surface 1b of the circuit board 1. The circuit board 1 is mounted with the semiconductor module 2 disposed in the housing 6.

Fan 7 blows the 1 st cooling air to 1 st air passage WP1 serving as fin 3 to cool fin 3. In embodiment 1, the fan 7 is provided on the one end 3a side of the fin 3. That is, the fan 7 is provided on the opposite side of the notch 4 c. The fan 7 sends out wind from the one end 3a side to the other end 3b side, thereby blowing the 1 st cooling wind. Thereby, the fan 7 forcibly air-cools the radiator 5.

The 1 st air vent 8 communicates between the inside of the housing 6 and the outside of the housing 6, and takes the 2 nd cooling air into the housing 6. The 1 st air vent 8 is provided above the half height of the highest portion of the height of the electronic component 10 from the surface 1a of the circuit board 1. Here, the height of the capacitor 10a, which will be described later, from the circuit board 1 is the highest in the electronic component 10. Therefore, the 1 st vent 8 is provided above the half height 15 of the uppermost portion 110a of the capacitor 10 a. In the semiconductor device shown in fig. 2, the other end 3b of the fin 3 is located in an upward direction (i.e., on the right side in the drawing). The 1 st vent 8 is arranged such that the center 8a of the 1 st vent 8 is located above the half height 15, and the entire 1 st vent 8 is located above the half height 15. In embodiment 1, the 1 st vent 8 is provided in the housing 6. Here, the 1 st vent 8 is provided on the other end 3b side of the fin 3, i.e., above the notch 4c of the base 4, on the upper surface 6a of the frame 6. In fig. 1, the shape of the 1 st vent 8 is shown as a rectangle, but the shape is not limited to a rectangle and is arbitrary. The 1 st vent 8 may be a pore or a mesh including a plurality of pores.

The 2 nd vent 9 penetrates one surface 4a and the other surface 4b of the base 4 in the frame 6. In embodiment 1, the 2 nd vent 9 includes the notched portion 4c of the base portion 4. Vent 2 9 may include at least a part of notch 4c of base 4. As shown in fig. 2, for example, the 2 nd vent 9 is preferably provided above the half height 15 of the uppermost portion 110a of the capacitor 10a, which is the highest electronic component 10. The 2 nd air vent 9 communicates between the inside of the housing 6 and the outside of the housing 6, and discharges the 2 nd cooling air taken into the housing 6 to the outside of the housing 6.

The 1 st vent 8 and the 2 nd vent 9 form the following 2 nd air passage WP 2: due to the pressure difference between the inside of the housing 6 and the outside of the housing 6 formed in the 2 nd vent 9 by the flow of the 1 st cooling air, the 2 nd cooling air is taken in from the 1 st vent 8 and discharged from the 2 nd vent 9 to the outside of the housing 6. In embodiment 1, the cross-sectional area of the 1 st vent 8 is about the same as the cross-sectional area of the 2 nd vent 9.

Electronic component 10 is disposed in housing 6 along 2 nd air passage WP 2. The electronic component 10 includes an electric electronic component, such as a capacitor 10 a. Alternatively, the electronic component 10 is, for example, another semiconductor module 10 b. The capacitor 10a is, for example, a large capacitor 10a larger than the semiconductor module 2 or the other semiconductor module 10 b. The electronic component 10 is not limited to the capacitor 10a, and may be, for example, a transformer or a coil. The frame 6 is attached to the base 4 of the heat sink 5 so as to cover the circuit board 1 and the electronic component 10. In addition, the housing 6 may be provided with an external connection terminal 11. The external connection terminals 11 are connected to the semiconductor module 2 and the electronic component 10 via the circuit board 1.

(Cooling operation of semiconductor device)

Next, the operation of the semiconductor device will be described. Fig. 4 is a diagram showing pressure distributions when air is blown into and out of the semiconductor device in embodiment 1. Fig. 5 is a diagram showing the flow velocity distribution when air is blown into and out of the semiconductor device in embodiment 1. Fig. 6 is a diagram showing temperature distributions when air is blown into and out of the semiconductor device in embodiment 1. Fig. 4 to 6 each show the analysis result by the finite element method (finite element method).

The size of the frame 6 is 90mm in depth × mm in width × mm in height 150mm in fig. 4, the vertical direction of the paper is the depth direction, the horizontal direction is the width direction, the vertical direction is the height direction, the size of the heat sink 5 is 90mm in depth × mm in width 150mm × mm in height 100mm, the size of the 1 st vent 8 is 50mm in depth × mm in width 20mm, the size of the notch 4c, that is, the 2 nd vent 9 is 50mm in depth × mm in width 20mm, the amount of heat generation of the semiconductor module is 20w, and other components are not heated, the fan 7 blows the 1 st cooling air with a wind speed of 5m/s, and further, no wind speed is set around the frame 6, and the outside air temperature of the frame 6 is 20 ℃.

By driving the fan 7, the 1 st cooling air flows from one end 3a to the other end 3b of the fin 3. As a result of the flow of the 1 st cooling air, as shown in fig. 4, the pressure outside the housing 6 is reduced at the 2 nd vent 9, that is, at the notch 4c of the base portion 4 in embodiment 1. Since the air in the frame 6 is surrounded by the frame 6 and the base 4, the pressure in the frame 6 is higher than the pressure of the air flowing through the fins 3 directly below the base 4. Since the gas flows from a high pressure place to a low pressure place, the air in the high pressure housing 6 is discharged to the outside of the low pressure housing 6 through the 2 nd vent 9 as shown in fig. 5. Since the pressure in the housing 6 is lowered by exhausting the air in the housing 6 through the 2 nd vent 9, the external air flows into the housing 6 from the outside of the housing 6 through the 1 st vent 8. As a result, an air passage is formed in which the 2 nd cooling air flows from the 1 st vent port 8 to the 2 nd vent port 9. The air passage through which the 2 nd cooling air flows is the 2 nd air passage WP2 shown in fig. 2, and the 2 nd air passage WP2 is formed to connect the 1 st vent port 8 and the 2 nd vent port 9. In fig. 5, although not shown, the resolution is insufficient, but the wind speed of the 2 nd cooling wind on the front surface 1a of the circuit board 1 is smaller than the wind speed of the 2 nd cooling wind on the capacitor 10 a. For example, the wind speed of the 2 nd cooling wind at the surface 1a of the circuit substrate 1 is lower than the wind speed of the 2 nd cooling wind that is the uppermost portion 110a of the capacitor 10a of the electronic component 10 that is the highest in height from the surface 1 a.

As shown in fig. 6, the semiconductor device cools the electronic components 10 such as the semiconductor module 2 and the capacitor 10a arranged in the vicinity of the 2 nd air passage WP2 through which the 2 nd cooling air flows, by the 2 nd cooling air. In particular, the upper portion of the capacitor 10a is cooled. The semiconductor device also cools the heat sink 5 by the 1 st cooling air, and as a result, the semiconductor module 2 is cooled.

(Effect)

In summary, the semiconductor device according to embodiment 1 includes: a heat sink 5 including fins 3 forming a 1 st air path WP1 through which the 1 st cooling air flows from one end 3a to the other end 3b, and a base 4 having a plate-like shape, the semiconductor module 2 being provided on one surface 4a of the base 4, the fins 3 being provided upright on the other surface 4 b; a frame 6 mounted on the base 4 of the heat sink 5 so as to cover the one surface 4a of the base 4, the semiconductor module 2, the electronic component 10 operating in association with the semiconductor module 2, and the circuit board 1 on which the electronic component 10 is mounted, and accommodating the semiconductor module 2 in a space formed between the one surface 4a and the frame; fan 7 for cooling fin 3 by blowing 1 st cooling air into 1 st air passage WP 1; a 1 st air vent 8 for communicating the inside of the housing 6 with the outside of the housing 6 and taking in the 2 nd cooling air into the housing 6; and a 2 nd vent 9 communicating the inside of the housing 6 and the outside of the housing 6, for discharging the 2 nd cooling air taken into the housing 6 to the outside of the housing 6. The 1 st vent 8 is provided at an upper portion of the electronic component 10 mounted on one surface (front surface 1a) of the circuit board 1 in the housing 6, with respect to a height 15 half of a portion (uppermost portion 110a) where the height of the circuit board 1 is highest. The 2 nd vent 9 penetrates one surface 4a and the other surface 4b of the base 4 in the frame 6. In the housing 6, the 1 st vent 8 and the 2 nd vent 9 form the following 2 nd air passage WP 2: due to the pressure difference between the inside of the housing 6 and the outside of the housing 6 formed in the 2 nd vent 9 by the flow of the 1 st cooling air, the 2 nd cooling air is taken in from the 1 st vent 8 and discharged from the 2 nd vent 9 to the outside of the housing 6. The speed of the 2 nd cooling air on one surface (surface 1a) of the circuit board 1 is lower than the speed of the 2 nd cooling air on the electronic component 10.

With the above configuration, the semiconductor device can form 2 nd air path WP2 through which the 2 nd cooling air flows between 1 st vent 8 and 2 nd vent 9. The semiconductor device can flow the 2 nd cooling air in the housing 6 without degrading the performance of the heat sink 5. Air stagnation generated in the vicinity of the semiconductor module 2 in the housing 6 can be eliminated, and hot air staying around the semiconductor module 2 can be discharged. Further, the semiconductor device cools the electronic components 10 mounted near the 2 nd air path WP 2. For example, even if a large electronic component 10 such as a capacitor 10a is mounted, the semiconductor device is efficiently cooled. As a result, the life of the capacitor 10a is prolonged, and the reliability of the semiconductor device is increased. First air vent 8 is located above height 15, which is half of uppermost portion 110a of capacitor 10a, among electronic components 10 mounted on surface 1a of circuit board 1. Therefore, the semiconductor device can efficiently exhaust air having a high temperature in the housing 6 without increasing the wind speed near the surface 1a of the circuit board 1. In addition, since foreign matter such as dust is less likely to adhere to the circuit board 1, measures against foreign matter adhesion such as a coating layer on the surface 1a of the circuit board 1 are not required. For example, when the wind speed near the surface 1a of the circuit board 1 is 0.3m/s, foreign substances such as dust and dirt are not easily attached, and therefore, a foreign substance attachment measure is not necessary. Therefore, the semiconductor device can be reduced in size, weight, and cost by satisfying the relationship of "the wind speed of 2 nd air path WP2 ≧ 0.3m/s ≧" the wind speed in the vicinity of surface 1a of circuit board 1 ". The wind speed is an example, and may be a wind speed to the extent that the semiconductor device does not malfunction due to dust or dirt. The positions of the 1 st vent 8 and the 2 nd vent 9 and the arrangement of the electronic components 10 described in embodiment 1 are examples, and are not limited to the above. The arrangement of the 1 st vent 8 and the 2 nd vent 9 may be determined according to the arrangement of the electronic components 10 mounted on the circuit board 1, for example. That is, the 1 st vent 8 and the 2 nd vent 9 may be provided so as to form the 2 nd air passage WP2 in accordance with the arrangement of the electronic component 10. In the semiconductor device according to embodiment 1, the housing 6 and the heat sink 5 surround the circuit board 1, the semiconductor module 2, and the electronic component 10, so that noise transmitted from the outside of the housing 6 to the inside of the housing 6 is reduced.

In addition, the 2 nd vent 9 of the semiconductor device according to embodiment 1 is provided at an upper portion of the circuit board 1 at a height 15 half of the highest portion (the uppermost portion 110 a).

In such a semiconductor device, the speed of the 2 nd cooling air on the surface 1a of the circuit board 1 can be made smaller than the speed of the 2 nd cooling air on the electronic component. Therefore, the semiconductor device can reduce the adhesion of foreign matters to the surface 1a of the circuit board 1 and exhaust the air having a high temperature in the housing 6.

In the semiconductor device according to embodiment 1, the 1 st vent 8 is provided in the housing 6. The base portion 4 includes a notch portion 4c penetrating the one surface 4a and the other surface 4b at least at a part of one side forming a plate-like shape. The side provided with the notch 4c is located on the other end 3b side of the fin 3. Vent No. 2 9 includes at least a part of notch portion 4 c.

With this configuration, the cooling performance in the housing 6 can be improved by merely adding the processing cost for forming the 1 st vent 8 and the 2 nd vent 9 without adding a cooling member such as the fan 7 to the semiconductor device. In addition, when the 1 st vent 8 is a mesh, dust entering the housing 6 can be prevented. The notch 4c may be configured to penetrate the inside of the frame 6 and the outside of the frame 6, and may not penetrate the fin 3 as long as it penetrates the base 4 as described above. The notch 4c as the 2 nd air vent 9 may be configured to allow the 2 nd cooling air to flow in a direction perpendicular to the 1 st cooling air flow direction. Even when the notch 4c as the 2 nd air vent 9 is provided on the upstream side of the 1 st cooling air, that is, on the one end 3a side of the fin 3, the cooling air flows into the housing 6 from the 2 nd air vent 9. However, considering that the cooling efficiency of the heat sink 5 is reduced due to a reduction in the volume of the 1 st cooling air flowing through the fins 3, the notch 4c is preferably provided on the other end 3b side of the fins 3.

In the semiconductor device according to embodiment 1, the fan 7 is provided on the one end 3a side of the fin 3, and blows the 1 st cooling air by sending air from the one end 3a side to the other end 3b side.

With this configuration, the 2 nd flow path WP2 for the 2 nd cooling air can be formed in the housing 6 without reducing the volume of the 1 st cooling air. That is, the electronic component 10 and the like in the housing 6 can be cooled without impairing the cooling effect of the heat sink 5.

The semiconductor device according to embodiment 1 further includes an electronic component 10, and the electronic component 10 is provided in the housing 6 along the 2 nd air passage WP2 and operates in association with the semiconductor module 2.

With this configuration, electronic component 10 is efficiently cooled by 2 nd cooling air flowing through 2 nd air passage WP2 formed at each position of 1 st vent 8 and 2 nd vent 9.

In addition, the semiconductor device according to embodiment 1 has a greater effect when a power semiconductor module that controls large power is mounted as the semiconductor module 2 than a semiconductor module that controls small power. The heat generation amount of the power semiconductor module is larger than that of the semiconductor module for controlling low power. Therefore, the heat sink 5 is mounted on the power semiconductor module, and the heat dissipation performance is improved. On the other hand, the power semiconductor device including the power semiconductor module is covered with the housing 6 to prevent contact with the outside as described above. Further, electronic components 10 and the like that operate in association with the circuit board 1 and the semiconductor module 2 are also provided in the housing 6. Since circulation of air in the housing 6 is hindered by the housing 6, a separate heat radiation design is required for the electronic component 10 and the like that are not mounted on the heat sink 5. According to the configuration of the semiconductor device in embodiment 1, since 2 nd air path WP2 for the 2 nd cooling air is formed in housing 6, circuit board 1, electronic component 10, and the like in housing 6 can be efficiently cooled even if the semiconductor device is a power semiconductor device.

(modification 1 of embodiment 1)

In the semiconductor device shown in embodiment 1, 2 nd air passage WP2 for the 2 nd cooling air is formed above other semiconductor modules 10b mounted on circuit board 1 and large electronic components 10 such as capacitor 10 a. Then, the 2 nd cooling air cools the components mounted on the circuit board 1. The structure and operation of the semiconductor device are not limited to this. The 2 nd air passage WP2 of the 2 nd cooling air formed in the housing 6 can be changed by changing the position of the 1 st air vent 8, the position of the 2 nd air vent 9, or the arrangement of the electronic components 10 mounted on the circuit board 1, and the electronic components 10 to be cooled can also be changed.

Fig. 7 is a cross-sectional view showing the structure of a semiconductor device in modification 1 of embodiment 1. The positions of the 1 st vent 8 and the 2 nd vent 9 are the same as those in embodiment 1, but the arrangement of the circuit board 1 is different from that in embodiment 1. The circuit board 1 of the semiconductor device according to modification 1 of embodiment 1 is mounted at a position that is inverted by 180 degrees with respect to the mounting position of the circuit board 1 of the semiconductor device shown in fig. 2. The 1 st air vent 8 is provided above the half height of the highest portion of the electronic component 10 from the back surface 1b of the circuit board 1. Here, the other semiconductor modules 10b have the highest height from the circuit board 1. Therefore, the 1 st vent 8 is provided above the half height 15 of the uppermost portion 110b of the other semiconductor module 10 b. In the semiconductor device shown in fig. 7, the other end 3b of the fin 3 is located in an upward direction (i.e., on the right side in the drawing). Here, the 1 st vent 8 is disposed such that the center 8a of the 1 st vent 8 is located above the half height 15. Although not shown, the entire 1 st vent 8 may be located above the half height 15 as in embodiment 1. 2 nd air passage WP2 for the 2 nd cooling air formed by 1 st vent 8 and 2 nd vent 9 is formed on the back surface 1b side of circuit board 1. Here, the back surface 1b of the circuit board 1 is a surface opposite to the front surface 1a on which the capacitor 10a is mounted.

With such a configuration, the semiconductor device can cool the circuit board 1 and the electronic component 10 and the like mounted on the rear surface 1b of the circuit board 1.

(modification 2 of embodiment 1)

Fig. 8 is a cross-sectional view showing the structure of a semiconductor device in modification 2 of embodiment 1. The circuit board 1 in modification 2 is mounted at a position rotated by 90 degrees with respect to the mounting position of the circuit board 1 of the semiconductor device in embodiment 1 shown in fig. 2. The 1 st vent 8 is provided in the side surface 6b of the frame 6. The side surface 6b is located on the one end 3a side of the fin 3. That is, the 1 st vent 8 and the 2 nd vent 9 are provided at diagonal positions of the circuit board 1. The 1 st air vent 8 is provided above a half height of a portion (uppermost portion 110a) where the height of the electronic component 10 from the surface 1a of the circuit board 1 is highest. In the semiconductor device shown in fig. 8, the front side of the drawing is the upper side. The 2 nd vent 9 is also preferably provided above the half height of the uppermost portion 110 a. In addition, large-sized electronic component 10 such as capacitor 10a mounted on circuit board 1 is disposed so as not to completely shield 2 nd air passage WP2 of 2 nd cooling air. Further, electronic component 10 to be cooled is disposed in the vicinity of 2 nd air passage WP2 of 2 nd cooling air.

With this configuration, 2 nd air passage WP2 for the 2 nd cooling air is formed between 1 st vent port 8 and 2 nd vent port 9 provided diagonally. The semiconductor device can cool the electronic component 10 to be cooled by the 2 nd cooling air.

(modification 3 of embodiment 1)

Fig. 9 is a cross-sectional view showing the structure of a semiconductor device in modification 3 of embodiment 1. The circuit board 1 in modification 3 is mounted at a position rotated by 90 degrees with respect to the mounting position of the circuit board 1 of the semiconductor device in embodiment 1 shown in fig. 2. The positions of the 1 st vent 8 and the 2 nd vent 9 are the same as those in embodiment 1. That is, the 1 st air vent 8 is provided above the half height of the portion (the uppermost portion 110a) where the height of the electronic component from the surface 1a of the circuit board 1 is the highest. In the semiconductor device shown in fig. 9, the front side of the drawing is the upper side. The 2 nd vent 9 is also preferably provided above the half height of the uppermost portion 110 a. In the housing 6, an electronic component 10 and an electronic component heat sink 12 for cooling the electronic component 10 are also provided. The mounting position of electronic component 10 mounted with electronic component heat sink 12 is a position overlapping 2 nd air passage WP2 of 2 nd cooling air flowing from 1 st air vent 8 to 2 nd air vent 9. Here, the electronic component 10 is another semiconductor module 10b different from the semiconductor module 2 mounted on the heat sink 5. The electronic component heat sink 12 is, for example, a heat sink smaller than the heat sink 5 on which the semiconductor module 2 is mounted.

With such a configuration, the semiconductor device can forcibly cool the electronic component heat sink 12, and further, can cool the electronic component 10 (the other semiconductor module 10 b). Therefore, the characteristic change due to the temperature change of the electronic component 10 becomes small, and the reliability of the semiconductor device in which the electronic component 10 is mounted increases. The heat sink 5 on which the semiconductor module 2 is mounted is disposed separately from the electronic component heat sink 12. Therefore, the semiconductor device can simultaneously cool the semiconductor module 2 and the electronic component 10 having different temperature rise rates.

(modification 4 of embodiment 1)