JP2003100938A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a semiconductor device that can reduce height and length in an insulating base and compose the insulating base inexpensively regarding a configuration for securing a creeping distance from the end face of a circuit pattern to a heat sink to at least specific dimensions in a semiconductor device where the circuit pattern is formed at the front side of the insulating base and at the same time the heat sink is joined to the back side. SOLUTION: In the semiconductor device where a circuit pattern is formed at the front side of an insulating base and at the same time the heat sink is joined to a back side, a groove section is formed along one outer periphery of the front or back side in the insulating base, a creeping distance from the circuit pattern to the heat sink is set to a specific value or more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device in which a circuit pattern is formed on the front surface side of an insulating substrate and a heat dissipation plate is joined to the back surface side.

[0002]

2. Description of the Related Art FIG. 10 shows, for example, Japanese Patent Laid-Open No. 61-5194.
FIG. 8 is a cross-sectional view showing a conventional semiconductor device disclosed in Japanese Patent Laid-Open No. 7-74, in which reference numeral 1 is an insulating base material, and projections 1a and 1b are formed on the peripheral edges of both surfaces thereof. 2 is a circuit pattern made of a copper foil formed on the surface of the insulating base material 1, 3 is a back surface pattern made of a copper foil formed on the back surface of the insulating base material 1, 4 is the insulating base material 1 and the circuit The insulating substrate is composed of the pattern 2 and the back surface pattern 3. Reference numeral 5 denotes a heat radiating plate, which has a joint portion 5a that faces the back surface pattern 3 and faces it, and a step portion 5b formed lower than the joint portion 5a. The part 5a is joined. Further, the stepped portion 5b of the protrusion 1b secures a spatial distance from the upper surface of the heat dissipation plate 5.

In this structure, the circuit pattern 2 described above is used.
Since the creepage distance from the end face 2a to the end face 3a of the back surface pattern 3 is along the protrusions 1a and 1b, the creepage distance is longer than in the case where no protrusion is present, and the withstand voltage is improved. That is, the predetermined withstand voltage is obtained by increasing the height or the width of the protrusions 1a and 1b to increase the creepage distance.

[0004]

The conventional semiconductor device is
In order to obtain a predetermined withstand voltage, the protrusions 1a and 1b are provided on the periphery of both surfaces of the insulating base material 1, and the height of the protrusions 1a and 1b is increased or the width is increased to increase the creepage distance. Was there. Therefore, the thickness of the expensive insulating base material 1 becomes large,
Alternatively, there is a problem that the area becomes large and the semiconductor device becomes expensive.

The present invention has been made to solve the above-mentioned problems, and the end face 2a of the circuit pattern 2 is formed.
It is an object of the present invention to provide a semiconductor device in which the creepage distance from to the end surface 3a of the back surface pattern 3 can be reduced in height and length of the insulating base material 1, and the insulating base material 1 can be configured at low cost.

[0006]

A semiconductor device according to a first aspect of the present invention is formed along the outer periphery of either the front surface side or the back surface side of an insulating base material, and the creepage distance from a circuit pattern to a heat sink is set. A groove portion having a predetermined value or more is provided.

Further, in the semiconductor device according to the second invention, a ridge is formed along the outer circumference of the insulating base material, and a groove along the outer circumference is provided in the ridge.

Further, in the semiconductor device according to the third aspect of the present invention, the ridge portion is formed of a resin insulating plate.

Further, in the semiconductor device according to the fourth aspect of the present invention, the semiconductor substrate is bonded so as to cover the outer periphery of either the front surface side or the back surface side of the insulating base material and the peripheral edge of the insulating base material, and from the circuit pattern to the heat sink. An insulating member is provided which has a creepage distance equal to or greater than a predetermined value.

Further, in the semiconductor device according to the fifth aspect of the present invention, a groove is formed in the insulating member along the outer periphery of the insulating base material, and the creepage distance from the circuit pattern to the heat sink is set to a predetermined value or more in the groove. It is composed.

Further, in the semiconductor device according to the sixth aspect of the present invention, the insulating plate is joined to the entire circumference of the heat dissipation plate on the side facing the insulating base material while being separated from the insulating base material.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. Embodiment 1 of the present invention will be described with reference to FIG. Note that FIG. 1 is a cross-sectional view of the semiconductor device. In the figure, reference numeral 1 denotes an insulating base material, and a plurality of groove portions 1d are formed along the outer peripheral portion 1c on the peripheral edge of the surface thereof. 2 is a circuit pattern made of a copper foil formed on the surface of the insulating base material 1, 3 is a back surface pattern made of a copper foil formed on the back surface of the insulating base material 1, 4 is the insulating base material 1 and the circuit The insulating substrate is composed of the pattern 2 and the back surface pattern 3. Reference numeral 5 denotes a heat radiating plate, which is joined to the back surface pattern 3 and faces the joint portion 5a.
It has a step portion 5b formed lower than a, and the joint portion 5a is joined to the back surface pattern 3 via a solder 6.

In this configuration, the circuit pattern 2 described above is used.
Since the creepage distance from the end face 2a of the back surface to the end face 3a of the back surface pattern 3 is along the plurality of groove portions 1d, the groove portion 1d
A predetermined creepage distance can be secured by determining the depth and the number of the. That is, a predetermined withstand voltage can be secured without increasing the thickness or width of the insulating base material 1. In addition,
In the first embodiment, the groove portion 1d only needs to secure a predetermined creepage distance, and is not necessarily provided all around the insulating base material 1 and may be provided partially.

Embodiment 2. The second embodiment of the present invention will be described with reference to FIG. 2 is a cross-sectional view of the semiconductor device. In the figure, reference numeral 1 is an insulating base material, and a ridge portion 1a is formed along the outer peripheral portion 1c on the surface side thereof, and a plurality of groove portions 1d are formed along the outer peripheral portion 1c on the ridge portion 1a. Has been done. With this configuration, the groove 1d is formed on the ridge 1a.
Since the depth dimension of the groove portion 1d can be increased, the number of the groove portions 1d can be reduced, the width dimension of the insulating base material 1 can be reduced, and the material of the expensive insulating base material 1 can be reduced. Withstand voltage can be secured with an inexpensive structure.

Embodiment 3. A third embodiment of the present invention will be described with reference to FIG. Note that FIG. 3 is a cross-sectional view of the semiconductor device. In the figure, 1 is an insulating base material, 7 is an insulating plate which is joined to the outer peripheral portion 1c on the front surface side of the insulating base material 1 and protrudes toward the front surface side of the insulating base material 1, and is molded with a resin such as epoxy resin. Consists of Reference numeral 7a denotes a plurality of grooves formed on the insulating plate 7 and extending along the outer peripheral portion 1c of the insulating base material. In this configuration, since the insulating plate 7 is configured separately from the insulating base material 1, the common insulating base material 1 is used.
The required creepage distance can be secured by simply changing the shape of the insulating plate 7, the expensive insulating base material 1 can be standardized, and the cost can be further reduced. In the third embodiment, the insulating plate 7 and the groove portion 7a may be provided as long as they can secure a predetermined creepage distance, and are not necessarily provided on the entire circumference of the insulating base material 1 but partially provided. May be.

Fourth Embodiment A fourth embodiment of the present invention will be described with reference to FIG. Note that FIG. 4 is a cross-sectional view of the semiconductor device. In the figure, reference numeral 1 denotes an insulating base material, and 8 denotes an outer peripheral portion 1c on the front surface side of the insulating base material 1 and a peripheral edge portion 1e of the insulating base material 1 which are joined to each other and project to the front surface side of the insulating base material 1. It is an insulating member. In this structure, since the insulating member 8 covers the peripheral edge portion 1e of the insulating base material 1, the size of the expensive insulating base material 1 can be reduced and standardized, and the cost can be further reduced. Note that the insulating member 8 can exert further effects by covering both the front surface side and the back surface side of the insulating base material 1 as shown in FIG.

Embodiment 5. A fifth embodiment of the present invention will be described with reference to FIG. Note that FIG. 6 is a cross-sectional view of the semiconductor device. Reference numeral 8a denotes a plurality of groove portions formed on the insulating member 8 along the outer peripheral portion 1c of the insulating base material 1. With this configuration, a predetermined creepage distance can be easily ensured by the number of grooves 8a, and the width dimension of the insulating base material 1 can be significantly reduced.

Embodiment 6. A sixth embodiment of the present invention will be described with reference to FIG. Note that FIG. 7 is a cross-sectional view of the semiconductor device. In the figure, reference numeral 9 is an insulating plate which is joined to the entire circumference of the heat dissipation plate 5 facing the insulating base material 1 while being separated from the insulating base material 1. 10 is solder on the circuit pattern 2
It is a semiconductor element bonded via the. With this configuration,
Even if the distance between the insulating base material 1 and the heat sink 5 is short and the space distance is small, insulation is performed by the insulating plate 9. Therefore, the withstand voltage between the circuit pattern 2 and the heat sink 5 is It becomes possible to depend on the creepage distance to the back surface pattern 3, and the withstand voltage characteristics are further improved. The insulating plate 9 between the adjacent insulating substrates 4 has the same effect even if it is separated as shown in FIG.

Embodiment 7. The seventh embodiment of the present invention will be described with reference to FIG. Note that FIG. 9 is a cross-sectional view of the semiconductor device. In the figure, reference numeral 5 denotes a heat dissipation plate, which has a joint portion 5a protruding in an area smaller than that of the insulating base material 1 and a step portion 5b formed so as to be lower than the joint portion 5a. It is bonded to the base material 1. 9 is the step portion 5b
Is an insulating plate bonded to the insulating base material 1 over the entire circumference on the side facing the insulating base material 1 while being separated from the insulating base material 1. This structure also has the same effects as the seventh embodiment of the present invention.

[0020]

Since the present invention is configured as described above, it has the following effects.

Since the groove portion is formed along the outer periphery of either the front surface side or the back surface side of the insulating base material and the creepage distance from the circuit pattern to the heat sink is set to a predetermined value or more, the insulating base material is provided. There is an effect that a predetermined withstand voltage can be secured without increasing the thickness or width.

A ridge is formed along the outer periphery of the insulating base material,
Since the groove is provided along the outer circumference of the ridge, the material of the expensive insulating base material can be reduced, and the predetermined withstand voltage can be secured with an inexpensive structure.

Since the ridge portion is made of a resin insulating plate,
Since the insulating plate is configured separately from the insulating base material, the expensive insulating base material can be standardized, and there is an effect that the cost can be further reduced.

The outer periphery of either the front surface side or the back surface side of the insulating base material and the peripheral edge of the insulating base material are covered and bonded.
Since the insulating member having the creepage distance from the circuit pattern to the heat dissipation plate is set to a predetermined value or more is provided, the size of the expensive insulating base material can be reduced and standardized, and further cost reduction can be achieved.

Since a groove is formed on the insulating member along the outer periphery of the insulating base material, and the creepage distance from the circuit pattern to the heat sink is set to a predetermined value or more in the groove, the number of grooves makes it easy. A predetermined creepage distance can be secured, and the width of the insulating base material can be significantly reduced.

Since the insulating plate is joined to the entire circumference of the heat dissipation plate facing the insulating base material so as to be separated from the insulating base material, there is an effect that the withstand voltage characteristic is further improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a semiconductor device showing a first embodiment of the present invention.

FIG. 2 is a sectional view of a semiconductor device showing a second embodiment of the present invention.

FIG. 3 is a sectional view of a semiconductor device showing a third embodiment of the present invention.

FIG. 4 is a sectional view of a semiconductor device showing a fourth embodiment of the present invention.

FIG. 5 is a sectional view of a semiconductor device showing another embodiment of the fourth embodiment of the present invention.

FIG. 6 is a sectional view of a semiconductor device showing a fifth embodiment of the present invention.

FIG. 7 is a sectional view of a semiconductor device showing a sixth embodiment of the present invention.

FIG. 8 is a sectional view of a semiconductor device showing another embodiment of the sixth embodiment of the present invention.

FIG. 9 is a sectional view of a semiconductor device showing an embodiment 7 of the present invention.

FIG. 10 is a cross-sectional view of a conventional semiconductor device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Insulating base material, 1a ridge, 1c outer peripheral portion, 1d groove, 1e peripheral portion, 2 circuit pattern, 4 insulating substrate, 5
Heat sink, 7 insulating plate, 7a groove, 8 insulating member, 8
a groove, 9 insulating plate.

Claims (6)

[Claims] 1. A semiconductor device comprising an insulating substrate having a circuit pattern formed on the front surface side of an insulating base material, and a heat dissipation plate joined to the insulating substrate, wherein the front surface side and the back surface side of the insulating base material are A semiconductor device having a groove portion formed along one of the outer peripheries, the groove portion having a creepage distance from the circuit pattern to the heat dissipation plate of a predetermined value or more. 2. The semiconductor device according to claim 1, wherein a ridge is formed along the outer periphery of the insulating base material, and a groove along the outer periphery is provided in the ridge. 3. The semiconductor device according to claim 2, wherein the ridge portion is formed of a resin insulating plate. 4. A semiconductor device comprising an insulating substrate having a circuit pattern formed on the front surface side of the insulating base material, and a heat dissipation plate joined to the insulating substrate, wherein the front surface side and the back surface side of the insulating base material are A semiconductor device, comprising: an insulating member, which is bonded to one of the outer peripheries so as to cover the peripheral edge of the insulating base material and has a creepage distance from the circuit pattern to the heat dissipation plate of a predetermined value or more. 5. The insulating member is formed with a groove along the outer periphery of the insulating base material, and the creepage distance from the circuit pattern to the heat sink is set to be a predetermined value or more in the groove. The semiconductor device described. 6. A semiconductor device comprising an insulating substrate having a circuit pattern formed on the surface side of an insulating base material, and a heat dissipation plate joined to the insulating substrate, the side of the heat dissipation plate facing the insulating base material. A semiconductor device characterized in that an insulating plate is bonded to the entire circumference of the insulating substrate while being separated from the insulating base material.