JP3011502B2 - Hybrid integrated circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid integrated circuit, and more particularly to a hybrid integrated circuit having a power mono IC in which a power section and a small signal section are integrated.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a hybrid integrated circuit on which a power semiconductor element is mounted is an insulating substrate (11) made of ceramics or aluminum whose surface is anodized.
A conductive path (12) provided in an arbitrary shape on the substrate (11), a heat sink (13) soldered on the conductive path (12), and fixed on the heat sink (13). Power devices such as power transistors (1
4) and its power element (14) and its surrounding conductive path (1).
2) and a bonding wire line (15) for connection, and a hybrid integrated circuit having a desired output is realized.

In a power element mounted on a heat sink of such a hybrid integrated circuit, a circuit constituting only a power stage is integrated, and a small signal system for driving a driver for driving the power element is used. Although not shown in FIG. 3, the circuit elements are connected on a conductive path near the power element, and both are connected.

[0004]

Therefore, in a conventional hybrid integrated circuit, a power element and a small signal element for driving the power element are separately mounted, so that a power hybrid having a large output of about 10 A or more is used. An integrated circuit can be realized. Recently, a power section and a small signal section for driving the power section have been integrated into one chip (for example, a MOSFE for high breakdown voltage).
T etc.) LSI elements have appeared. The power output of such a device is not a large output as in the conventional hybrid integrated circuit described above, but an output of about 1 to 10 A.

However, in consideration of heat radiation, the thickness of the heat sink needs to be at least about 2.5 to 3 mm, and the thickness of the heat sink is about 200 to connect the electrode of the power section and the conductive path.
Although a thick Al wire having a diameter of μ can be connected by bonding, a thin Al wire having a diameter of about 40 μ connecting an electrode of a small signal portion and a conductive path cannot be connected by bonding, and has a power portion and a small signal portion. That is, a so-called power mono IC cannot be mounted on a conventional hybrid integrated circuit.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and a hybrid integrated circuit according to the present invention includes a hybrid integrated circuit board having good thermal conductivity and A heat sink fixed to a predetermined position of the conductive path formed on the heat sink, a power circuit part fixed on the heat sink and connected to the nearby conductive path and wire wire, and a small signal circuit for driving the power circuit part; And a power semiconductor element integrated into a single chip, and only a relatively thin wire for a small signal circuit of the power semiconductor element is connected to a conductive path via a relay member disposed around the heat sink. It is characterized by being connected.

Further, a hybrid integrated circuit according to the present invention comprises:
A hybrid integrated circuit board having good thermal conductivity, a heat sink fixed to a predetermined position of a conductive path formed on the substrate, and a conductive path fixed to the heat sink and connected to a nearby conductive path and wire line A power semiconductor element in which a power circuit section and a small signal system circuit for driving the power circuit section are integrated into one chip; Is connected to the conductive path via a surface-mount type relay member arranged around the surroundings and having electrodes formed on the top and bottom surfaces,
A relatively thick wire for a power circuit is directly connected to the conductive path.

[0008]

In the hybrid integrated circuit constructed as described above, since the surface mounting type relay member is provided around the heat sink, the power circuit portion and the power circuit portion which cannot be mounted by the conventional structure are provided. A power mono type power semiconductor element in which a small signal circuit for driving the power circuit unit and a small signal circuit are integrated into one chip can be fixedly mounted. That is, a power semiconductor element that requires bonding wire connection between a thin wire (about 30 μm to 40 μm) and a thick wire (about 200 μm to 300 μm) can be fixedly mounted on a heat sink.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the embodiments shown in FIGS. FIG. 1 is an enlarged sectional view of a main part of a hybrid integrated circuit according to the present invention.
(2) is an insulating resin layer, (3) is a conductive path, (4) is a heat sink, (5) is a power semiconductor element, (6) is a relay member, and (7) is a wire.

As the hybrid integrated circuit substrate (1), an aluminum substrate having excellent heat conductivity is used, and an aluminum oxide film is formed on the surface of the substrate by an anodic oxidation method which is a well-known technique. A conductive path (3) having a desired shape is formed on the substrate (1) by means such as copper foil or metal plating via an insulating resin layer (2) such as an epoxy resin. At a predetermined position on the conductive path (3), a plurality of circuit elements such as transistors, chip resistors, and chip capacitors are fixedly mounted, though not shown. On the other hand, power circuit elements are mounted via a heat sink (4).

The power semiconductor element (5) used in the present embodiment is not one in which only a power circuit is formed, such as a power transistor, but includes a power circuit section and a small signal circuit for driving the power circuit section. One chip,
For example, a power mono IC such as a high breakdown voltage MOSFET is used. When such an element (5) is connected to the conductive path (3) on the substrate (1), two types of wire lines (7) are required. That is, about 2 electrodes are formed in the power circuit area.
A relatively thick Al wire with a diameter of 00μ to 500μ (7A)
The electrodes formed in the small signal circuit area are connected using a relatively thin wire (7B) of Al or the like having a diameter of about 20 to 50 μm.

On the other hand, the heat sink (4) is made of a material such as copper, and the thickness of the heat sink (4) is about 2.5 mm to 3.5 m in consideration of heat dissipation of the power semiconductor element (5).
m is required. The heat sink (4) is formed to have substantially the same size as the power semiconductor element (5), and the element (5) is fixed on the heat sink (4) with a brazing material such as solder.

A feature of the present invention is that a relay member (6) is arranged around a heat sink (4) to which a power semiconductor element (5) is fixed, and a thin A for a small signal system circuit is provided.
1 is connected to the conductive path (3) via the relay member (6). The relay member (6) is formed of an insulating resin such as epoxy or an insulating material such as ceramics. The relay member (6) used in the present embodiment is formed in a frame shape and surrounds the heat sink (4).
Can also be enclosed.

Electrodes are formed on the top and bottom of the relay member (6). That is, the conductor (6X) for connecting the conductive path (3) and the electrode of the small signal circuit of the power semiconductor element (5) is formed on the side surface of the relay member (6). Such a conductor (6X) can also be formed by plating or etching copper or the like, or by processing a metal lead terminal and integrating it with the relay member (6).

As described above, the bottom electrode (6B) of the relay member (6) is soldered on the conductive path (3) extending around the heat sink (4) so as to surround the heat sink (4). At this time, it is necessary to keep the step between the relay member (6) and the power semiconductor element (5) at about 1 mm in order to enable bonding of a thin wire (7B) made of Al or the like. The wall thickness is about 0.4mm to 1.4mm
It needs to be about as high.

After the heat sink (4) having the power semiconductor element (5) mounted on the substrate (1) and the relay member (6) are fixedly mounted with a brazing material such as solder, a small signal of the power semiconductor element (5) is formed. The electrode formed in the system circuit area and the upper electrode (6A) of the relay member (6) are connected by a thin wire (7B) of Al or the like. For example, the base and emitter electrodes formed in the power circuit region of the power semiconductor element (5) and the conductive path (3) on the substrate (1) are connected by a thick Al wire (7A).

After connecting the power semiconductor element (5) and the peripheral conductive path (3), the power semiconductor element (5) and the wire (7) are sealed with a sealing resin layer such as an epoxy resin (not shown). Is done.

[0018]

As described in detail above, according to the present invention,
By arranging the relay member around the heat sink, it is possible to mount a so-called power mono type power semiconductor element in which the power circuit section and a small signal circuit for driving the power circuit section are integrated into one chip. .

Further, the use of the surface-mount type relay member makes it possible to mount a power mono type power semiconductor element without significantly lowering the board mounting density.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part showing an embodiment of the present invention.

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a sectional view showing a conventional hybrid integrated circuit.

[Explanation of symbols]

 (1) Hybrid integrated circuit board (2) Insulating resin layer (3) Conductive path (4) Heat sink (5) Power semiconductor element (6) Relay member (7) Wire wire

Claims (2)

(57) [Claims] 1. A hybrid integrated circuit board having good thermal conductivity, a heat sink fixed to a predetermined position of a conductive path formed on the substrate, and a conductive path and a wire fixed on and adjacent to the heat sink. A power semiconductor element in which a power circuit unit connected to the line and a small signal system circuit for driving the power circuit unit are integrated into one chip; a relatively thin wire for the small signal system circuit of the power semiconductor element; Only the line is arranged in the peripheral portion surrounding the heat sink, and the step with the power semiconductor element is within a predetermined range.
The hybrid integrated circuit is connected to the conductive path via the relay member formed as described above . 2. A hybrid integrated circuit board having good thermal conductivity, a heat sink fixed to a predetermined position of a conductive path formed on the substrate, and a conductive path and a wire fixed on and adjacent to the heat sink. A power semiconductor element in which a power circuit portion connected to the power circuit and a small-signal circuit for driving the power circuit are integrated into one chip; a relatively thin wire line for the small-signal circuit of the power semiconductor element; Only is disposed in a peripheral portion surrounding the heat sink, and a step from the power semiconductor element is within a predetermined range.
Is connected to the conductive path via a relay member formed as
A hybrid integrated circuit, wherein a relatively thick wire for a power circuit is directly connected to a conductive path.