JPH09186287A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device having a uniform heat distribution without using an insulating board. SOLUTION: When lead frames 51 to 519 electrically insulated from each other are provided in the package of a multi-chip module 2 formed of sealing material and a plurality of electronic components including at least two or more heating components 61 , 62 and one or more sub-chips 31 , 32 are mounted thereon, the two or more components 61 , 62 are disposed on lead frames 51 , 52 disposed at both ends in a package 7. Mounting means 111 , 112 for mounting radiating fins are provided at both ends of the package. Even if an insulating board is not provided, the temperature distribution becomes uniform. When the frames 51 , 52 disposed with the components 61 , 62 are widely formed, the distribution becomes further uniform.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the technical field of semiconductor devices that do not use an insulating substrate, and more particularly to a multi-chip module having a plurality of heat-generating components.

[0002]

2. Description of the Related Art In recent years, the size and density of electronic devices have been increasing, and power devices, which have been conventionally used as individual components, have both a drive circuit and a protection circuit incorporated in one package. It has been increasingly used as a semiconductor device. Such a conventional semiconductor device is called a hybrid IC, and when a plurality of power devices are housed in the package, the uniformity of heat distribution is improved and at the same time the power devices are electrically insulated. In order to do so, a power device has been mounted on an insulating substrate made of a ceramic material such as alumina.

A prior art hybrid IC is shown in FIG.
The hybrid IC 102 has five terminals 108 and one package 107 made of epoxy resin. Is provided with an insulating substrate 109 made of alumina.

Copper wiring films 101a and 101b electrically insulated from each other are provided on the surface of the insulating substrate 109, and the power device 106 is provided on each of the copper wiring films 101a and 101b.
a and 106b are fixed by solder. A circuit region 112 is provided on the insulating substrate 109 so as to be insulated from the copper wirings 101a and 101b. Within the circuit region 112, sub-chips 103a, 1
03b are arranged and configured to be thermally coupled to the power devices 106a and 106b by the insulating substrate 109.

The power devices 106a and 106b are arranged above the surface of the insulating substrate 109, while the circuit region 112 is arranged below the surface of the insulating substrate 109 and provided in the circuit region 112. The bonding pad 114 and the terminal 108 separately arranged below the insulating substrate 109 are configured to be easily connected by the gold wire 104.

Further, each power device 106a, 106b
The bonding pads provided on the surface are connected to the bonding pads in the circuit area 112 by the gold wire 104, respectively, and are connected to the control ICs 106a and 106b and the terminals 108 via the circuit area 112. The bottom surfaces of the power devices 106a and 106b are connected to the terminals 108 by the gold wire 104 connected to the copper wirings 101a and 101b, respectively. Similarly, the bonding pads provided on the surfaces of the sub chips 103a and 103b are connected to the terminals 108 by the gold wire 104 through the circuit region 112, respectively.

In such a hybrid IC 102,
Since the power devices 106a and 106b are arranged on the insulating substrate 112, the power devices 106a and 1
The heat generated by 06b is transmitted through the insulating substrate 112 and dispersed in the package 107, so that the heat distribution in the package 107 becomes uniform, and the insulating substrate 109 directly heats the circuit region 112. Since the temperature distribution in 103a and 103b is also uniform, it has been widely used in circuits that handle large currents.

However, in order to reduce the cost, reduction of the insulating substrate 109 is required, and in recent years, the insulating substrate 1 has been reduced.
09 or copper thin films 101a and 101b, hybrid ICs made of a metal material such as aluminum or a copper alloy and having electronic components such as semiconductor chips directly mounted on lead frames separated from each other have come to be used. .

Since such a lead frame is formed so as to be electrically insulated from each other, the electronic parts to be mounted are connected by gold wire wire bonding, and one end is molded into a terminal shape to the outside of the package. By deriving it, a hybrid IC that can be mounted on a printed circuit board can be configured, and thus has been attracting attention in recent years.

However, in such a hybrid IC, the thermal coupling between the electronic components arranged inside is performed by the sealing material that constitutes the package. As such a sealing material, a molding material such as epoxy resin, which has a lower thermal conductivity than metals and ceramics, is usually used, and therefore, when electronic parts are arranged in the same manner as in a conventional hybrid IC. However, there is a problem that the heat distribution in the package becomes non-uniform and the temperature rises partially. Such non-uniform heat distribution not only lowers the heat dissipation efficiency, but when the temperature distribution in the sub-chip is also non-uniform, it may cause circuit malfunction in the sub-chip due to heat balance problem. , The solution was desired.

[0011]

The present invention was created in order to solve the above-mentioned disadvantages of the prior art, and its purpose is to obtain a semiconductor device capable of obtaining a uniform heat distribution without using an insulating substrate. To provide.

[0012]

In order to solve the above-mentioned problems, the invention according to claim 1 is configured such that a package made of a sealing material and a lead housed inside the package are configured so as not to come into contact with each other. A semiconductor device having a frame and a plurality of electronic components including at least two or more heat-generating components and one or more sub-chips, wherein the electronic components are provided on the lead frame. The planar shape is formed in a rectangular shape, and mounting means for closely fixing the semiconductor device to the heat radiation fins is provided at both ends thereof, and the temperature distribution of the package is made uniform,

According to a second aspect of the present invention, a package made of a sealing material is configured so as not to contact each other,
A semiconductor device having a lead frame housed inside the package, and a plurality of electronic components including at least two or more heat generating components and one or more sub chips, the electronic components being provided on the lead frame. The heat generating component is provided on lead frames located at both ends in the package, and is configured to make the temperature distribution of the package uniform,

According to a third aspect of the present invention, in the semiconductor device according to any one of the first and second aspects, the area of the lead frame on which the heat generating component is provided has a heat generation position above the lead frame. It is characterized in that it is formed to be more than twice the area of the component.

According to the above-described structure of the present invention, when the lead frames are provided in the package of the semiconductor device made of the encapsulating material, the lead frames are configured so as not to contact each other, and are electrically insulated from each other. Since this is done, it becomes possible to mount a plurality of electronic components including at least two or more heat generating components and one or more sub chips on the surface thereof.

In such a semiconductor device, since a rigid insulating substrate is not built in, the package is apt to warp or distort due to a temperature rise. If mounting means for closely fixing the semiconductor device to the heat radiation fins is provided at both ends of the package, and heat-generating components are arranged at both ends of the package, even if the package is warped, the portion that generates the most heat in the package can be provided. Since it can be closely attached to the heat dissipation fin, the heat dissipation of the semiconductor device is improved and the heat distribution can be made uniform. In addition, if the heat-generating components are provided on the lead frames located at both ends of the package, the heat distribution can be made uniform without providing an insulating substrate. The distance between the component and the sub chip can be increased, and the temperature gradient in the sub chip can be made gentle.

If the lead frame on which the heat-generating component is arranged is formed wide, the heat generated by the heat-generating component is transferred to the lead frame and diffused into the package. The heat distribution can be made more uniform. In this case, the soaking property is good when the area of the lead frame is set to be twice or more the area of the heat-generating component arranged thereon.

[0018]

Embodiments of the present invention will be described with reference to the drawings. Referring to FIG. 1, reference numeral 2 is a semiconductor device according to an embodiment of the present invention, which is generally called a multi-chip module. This multi-chip module 2 has a package 7 formed by transfer molding of epoxy resin. The package 7 has a rectangular shape with a thickness of about 4 mm and a plane of about 50 mm × 20 mm. Is being done.

Lead frames 5 _{1 to} 5 ₁₉ are housed inside, and one end of each of the lead frames 5 _{1 to} 5 ₁₉ is arranged on one side surface of the package 7 and formed into a rod-shaped terminal 8 ₁ to. 8 ₁₉ are electrically and mechanically connected.
Further, each of the terminals 8 ₁ to 8 ₁₉ is led out from one side surface of the long side of the package 7 and can be formed into a ZIP (zigzag inline package) type terminal array in a later step.

The lead frames 5 _{1 to} 5 ₁₉ are formed in advance so as to be separated from each other, and can be integrally handled by a tie bar that connects the terminals 8 ₁ to 8 ₁₉ in series during transfer molding. But package 7
After the formation of the tie bar, the tie bar is cut and each of the terminals 8 ₁ to 8 ₁₉ is cut.
Is separated, the electrical short-circuit state of each of the lead frames 5 _{1 to} 5 ₁₉ is eliminated.

Each of the lead frames 5 _{1 to} 5 ₁₉ is made of a copper alloy having electrical conductivity. Among them, the lead frames 5 ₁ and 5 ₁₉ located at both ends have a die formed in a large area. Bonding portions 13 ₁ and 13 ₂ are provided, and power MOS-FET chips 6 ₁ and 6 ₂ which are heat-generating components are arranged on the die bonding portions 13 ₁ and 13 ₂ and fixed by soldering. ing. The areas of the lead frames 5 ₁ and 5 ₁₉ are made to be at least twice as large as the areas of the power MOS-FET chips 6 ₁ and 6 ₂ arranged thereon, and the thermal resistance is reduced. Has been done.

The lead frames 5 ₁ , 5 ₁₉ are as wide as possible so that heat can be transferred to the entire package 7.
Overhangs 10 ₁ and 10 ₂ are also formed in portions other than the current path, and when the power MOS-FET chips 6 ₁ and 6 ₂ generate heat, the heat is transmitted to the lead frames 5 ₁ and 5 _19. The heat distribution is performed even in a portion of the package 7 where no electronic component is arranged, so that the temperature distribution of the entire package 7 becomes uniform.

The two power MOS-FET chips 6 ₁ and 6 ₂ are arranged apart from each other at a position away from the side surface from which the terminals 8 ₁ to 8 ₁₉ are led out. It is located near both ends (near left and right) in the longitudinal direction. In addition, each power MOS-FET
Chips 6 ₁ and 6 ₂ are the distance from the short side of the package 7,
The power MOS-FETs 6 ₁ and 6 ₂ are arranged so as to be spaced apart from each other so as to be substantially equal to each other, and when the current flows through each of the power MOS-FETs 6 ₁ and 6 ₂ to generate heat, the heat is uniformly distributed in the package 7. Is configured.

In addition, each power MOS-FET chip 6 ₁ ,
A wide tip portion of the lead frame 5 ₁₆ is located at an intermediate position of 6 ₂ , and a sub chip 3 ₂ which is an electronic component is fixed on the surface by a silver paste. Therefore, each power MOS-FET chip 6 ₁ ,
When 6 ₂ generates heat, the sub-chip 3 ₂ is evenly heated so that uneven heat distribution does not occur in this chip.

Further, the tip portion of the lead frame 5 ₁₀ is formed wider, a nearby each terminal 8 _{1-8 19} package 7 is derived, the die bonding portion 13
_1, 13 ₂ is located at a substantially equal distance from the sub chip 3 ₁ is fixed with a silver paste which is an electronic component on the surface. Therefore, the sub chip 3 ₂ are ₁ two power MOS-FET chip 6, from 6 ₂ at a substantially equal distance, equally subjected to heat generation of the power MOS-FET chip 6 _1, 6 _2, in the chip In order to prevent uneven heat distribution.

The above-mentioned sub chips 3 ₁ and 3 ₂ have a power MO.
This is a control IC for driving and controlling the S-FET chips 6 ₁ , 6 ₂ , and the bonding pads provided on the surface of the sub chips 3 ₁ , 3 ₂ are connected by a gold wire 4a for connecting the chips to each other. _1, 3 ₂ of the internal circuit to each other are configured so as to be electrically connected to each other. Further, the other bonding pads on the sub chips 3 ₁ and 3 ₂ and the bonding pads on the surface of the power MOS-FETs 6 ₁ and 6 ₂ are connected to the lead frame 8 ₂ through the gold wire 4b for connecting the chip and the lead frame. 8 ₁₈ are respectively connected to, and insert the pin 8 _{1-8 19} on the printed circuit board and implemented by soldering, is configured to be operated with this multi-chip module 2.

The back surface of the package 7 is formed smoothly, and when mounted on a printed circuit board, a heat radiation fin can be adhered and fixed to the back surface of the multi-chip module 2 to increase heat dissipation. There is. Generally, in a package formed by transfer molding of epoxy resin, when there is no rigid insulating substrate inside, when heated due to the difference in the thickness of the epoxy resin on the front and back of the lead frame It is known that warpage is likely to occur in the longitudinal direction. In this multi-chip module 2, the power MOS-FET chips 6 ₁ and 6 ₂ are located near the short side of the package 7, and holes 11 ₁ and 11 _{2 as} mounting means are provided on the short side. Therefore, if screws are inserted into the holes 11 ₁ and 11 ₂ and the heat radiation fins and the multi-chip module 2 is screwed and fixed to the heat radiation fins, even if the package 7 warps in the longitudinal direction, the power MOS -It is possible to maintain close contact between the heat generating portions where the FET chips 6 ₁ and 6 ₂ are located and the heat radiation fins.

Above, two power MOs are used as heat-generating components.
Although the multi-chip module 2 having the S-FET chips 6 ₁ and 6 ₂ has been described, the number of heat-generating components is not limited to that. If you have 3 heating components,
It is advisable to arrange them at the positions on the vertices of the triangle, and further arrange the sub-chips near the center of the triangle. When there are four heat-generating components, each heat-generating component may be arranged at a position on the apex of the quadrangle, and the sub chip may be arranged near the center of the quadrangle. The same applies when the number of heat-generating components is five or more. In those cases, it is convenient to arrange each sub-chip at a position approximately equidistant from each heat-generating component because the uniformity of heat distribution in the sub-chip is enhanced.

The above-mentioned heat-generating component is a power MOS-F.
The invention is not limited to ET, but widely includes electronic components that can be mounted in a multi-chip module, such as a bipolar transistor chip and a thyristor chip, that generate heat when used. Further, the material of the package is not limited to the epoxy resin, and a wide range of materials such as silicon resin that can form a multi-chip module package are included. As described above, the material for fixing the electronic component to the lead frame is not limited to solder or silver paste. The material of the lead frame is also
Any material that has electrical conductivity and on which electronic components can be mounted may be used, but high thermal conductivity is desirable.

[0030]

The heat distribution of the multi-chip module can be made uniform without incorporating an insulating substrate. Further, the heat distribution in the sub chip does not become non-uniform, and no malfunction occurs. Even if warpage or distortion occurs in the package of the multi-chip module, the heat generating portion does not separate from the heat radiation fin.

[Brief description of the drawings]

FIG. 1 is a plan view of a multi-chip module according to an embodiment of the present invention.

FIG. 2A is a perspective view of a conventional hybrid IC. FIG. 2B is a diagram for explaining the inside.

[Explanation of symbols]

2 ... Multi-chip module 3 ₁ , 3 ₂ ...... Sub chip 5 _{1 to} 5 ₁₉ ...... Lead frame 6 ₁ , 6 ₂ ...... Heat generating component 7 ...... Package 11 ₁ , 11 ₂ ...... Mounting means

Claims (3)

[Claims] 1. A package including a package made of an encapsulating material, a lead frame configured so as not to contact each other and housed inside the package, at least two or more heat-generating components, and one or more sub-chips. A semiconductor device having a plurality of electronic components, wherein the electronic components are provided on the lead frame, wherein the planar shape of the package is formed into a rectangle, and both ends of the package are provided for closely fixing heat radiation fins. A semiconductor device, comprising mounting means, configured to make the temperature distribution of the package uniform. 2. A package including a package made of an encapsulating material, a lead frame configured so as not to come into contact with each other and housed inside the package, at least two or more heat-generating components, and one or more sub-chips. A semiconductor device having a plurality of electronic components, wherein the electronic components are provided on the lead frame, wherein the heat generating components are provided on lead frames located at both ends in the package, and the temperature of the package is A semiconductor device having a uniform distribution. 3. The lead frame provided with the heat-generating component is formed to have an area that is at least twice as large as the area of the heat-generating component located on the lead frame. The semiconductor device according to claim 1.