JPH0818184A - Hybrid integrated circuit device - Google Patents

Abstract

PURPOSE:To obtain a hybrid integrated circuit device (HIC) being employed in a fuel pump controller in which the manufacturing and assembling work is facilitated while reducing the size. CONSTITUTION:Since a protrusion 2 of a heat plate 1 is substantially as high as the surface of an Al pad on an HIC board 6, a bonding face 8 is ensured positively and since it can be provided closely to the fringe of the HIC board 6, contamination due to adhesive of the HIC board 6 is eliminated thus stabilizing the bonding performance. Furthermore, when the heat plate 1 is pressed against the housing 7 and bonded thereto, a recess 11 made in the bonding face along the outer periphery thereof prevents the adhesive 5 from spreading to the outside of the housing and influencing other work adversely. When the fins 9 are fixed to the heat plate 1 depending on the heating value, the common part can be formed on the same production line and the productivity 15 enhanced. This structure realizes overall size reduction and reduced the manufacturing cost by facilitating the automation.

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 device represented by a fuel pump controller.
The present invention relates to a hybrid integrated circuit device of a type including a housing and a heat dissipation plate and covered with a metal cover.

[0002]

2. Description of the Related Art Conventionally, a fuel pump controller is often constructed as a hybrid integrated circuit device (hereinafter referred to as HIC device) using a housing such as an insert-molded resin case. for,
The device is covered with a metal cover such as aluminum (Al) or iron (Fe). In addition, this cover may be connected to the GND (ground) of the internal circuit in order to improve the shielding effect. Furthermore, it is common for the internal circuit to generate heat, and the metal member is used as a heat sink that is a part of the housing.
It is also practiced to radiate this heat.
In the prior art, aluminum die casting or the like of a metal portion which is a part of the housing is ground to perform wire bonding, or a connecting metal piece is welded or soldered to ground.

Of these metal parts, the internal circuit (HI
Various materials such as aluminum die castings and plate materials have been used as a metal for holding the C substrate), and the metal plate is often used for simple products because of its heat dissipation structure. In many cases, a HIC substrate or the like is adhered to this metal plate to be held and fixed, and the metal plate is hermetically adhered to the housing. This is because if there is a gap between the metal plate and the case, leakage may occur when filling the gel agent (surface protective agent) to protect the surface of the internal circuit from moisture and dust, or conversely moisture from the outside. This is to prevent inconveniences such as invasion of the internal circuit and electric erosion of the internal circuit. Further, as a matter of course, this metal plate also has a function of playing a role as a heat dissipation plate when the elements of the internal circuit generate heat.

[0004]

However, each of the above points has the following problems. (a) First, as a technique for grounding the metal part and the GND of the internal circuit (HIC board), when the wire bonding is performed from the internal circuit GND to the heat sink that holds the internal circuit, hold the HIC board etc. on this heat sink. If the adhesive adheres to the bonding area, the bonding becomes defective, which causes a reduction in product yield. That is, as shown in FIG. 3, a region a where the adhesive 05 protrudes at the bonding portion between the heat dissipation plate 01 and the HIC substrate 06 and a region where the housing 07 and the heat dissipation plate 01 are bonded to form a fillet. b exists, the bonding area must avoid the areas a and b, and in order to secure the bonding area c, the heat sink 01
I have no choice but to increase. For this reason, the bonding wire must be taken long, and it is easy for the contact to occur due to the wire sagging, and if the bonding area is reduced as much as possible, the wire will come close to the housing, and the adhesive will not It is also possible to apply stress to the wire by, for example, adhering to the wire to reduce the reliability of the wire connection.

(B) In order to prevent a gap between the heat sink 01 and the housing 07, measures such as enlarging the adhesive surface and increasing the amount of adhesive applied are taken. As shown in FIG. 3, in the method in which the heat dissipation plate 01 is fitted and bonded like a lid by providing a step on the bonding portion of the housing 07, it is difficult to automate the work of fitting the heat dissipation plate 01 like a lid. They have to rely on work, resulting in poor assembly. In addition, a method of adhering without steps to increase the outer dimension to increase the adhering area is not desirable from the viewpoint of downsizing (Fig. 7 (b)), and in some cases, the metal cover shape or the like becomes complicated. To bring. In addition, excess adhesive will stick out and come into contact with the parts inside the housing, causing reliability problems. If it sticks out to the outside as shown in Fig. 7 (a), it will adhere to the process jig etc. As a result, the appearance is not good and the appearance is not good.

(C) When the insert-molded resin case, which is the housing, is commonly used according to the variety of products, the control unit of the internal circuit is made common and the drive system element (for example, power transistor etc.) is changed. However, at this time, the heat generation amount of the drive system element of the internal circuit varies depending on the product, and the heat dissipation plate to be attached must change the plate thickness and area corresponding to the heat generation amount. The manufacturing process for adhering the substrate that constitutes the internal circuit to the heat sink is performed at a relatively early stage, and at that time, dividing the process according to the type of the heat sink is a complicated and costly factor. There is a problem.

Therefore, an object of the present invention is to provide a hybrid integrated circuit device (HI) represented by a fuel pump controller or the like.
In C), it is to provide a configuration that facilitates miniaturization and is easy to manufacture and assemble.

[0008]

In order to solve the above-mentioned problems, the structure of the present invention comprises a housing, a metal member (metal plate) also serving as a heat dissipation plate is adhered to the housing, and the circuit board is In a hybrid integrated circuit device sealed in a housing, having a protrusion on a part of a surface of the heat dissipation plate to which the circuit board is bonded,
Wire bonding is performed between the pad portion of the circuit board and the upper surface of the protrusion provided at substantially the same height as the pad portion. The structure of another invention is also characterized in that, in the above hybrid integrated circuit device, a radiation fin having a size corresponding to the amount of heat generated by the circuit board is fixed to the outside of the radiation plate. Also, in the above hybrid integrated circuit device, the present invention also has a concave portion at an outer peripheral corner portion of an adhesion surface of the housing for adhering the heat dissipation plate, and the adhesive that protrudes when the heat dissipation plate is adhered to the concave portion. It is characterized in that the adhesive is contained and the adhesive does not squeeze out of the housing, and in particular, the concave portion is a round chamfer, a C chamfer, a step or a notch.

[0009]

[Function] Since the protrusion provided on the heat dissipation plate is substantially higher than the surface to which the HIC board is bonded and is substantially flush with the Al pad surface of the HIC board, the bonding surface is surely secured and the edge of the HIC board is secured. Can be provided in a portion close to.
Further, the bonding area is not contaminated by the adhesive of the HIC substrate. Also, when the heat sink is bonded to the housing, a recessed area is provided along the outer periphery of the portion where the heat sink and the housing contact, so that the adhesive does not stick out of the housing when pressing the heat sink. I don't. Further, a radiation fin having a predetermined size is attached to the radiation plate according to the amount of heat generated by the substrate.

[0010]

By providing the bonding surface of the protrusion on the heat dissipation plate, the bonding of the HIC substrate to the heat dissipation plate is performed at substantially the same height, so that the bonding conditions do not change and the bondability is stabilized. The position of the bonding surface can be arranged near the circuit board, and the wire for bonding can be shortened, and the sagging of the wire is slightly reduced to prevent it from affecting other parts. Further, since the bonding area is not contaminated with the HIC adhesive, wire bonding can be performed promptly and reliably. Also HI
Depending on the amount of heat generated by C, heat radiation fins can be additionally attached to the heat radiation plate, so common parts are in the same process (same manufacturing line)
Can be formed with, improving productivity. When the heat dissipation plate is adhered to the housing, excess adhesive does not squeeze out, so that the assembling property of the device is not deteriorated and the appearance is clean.
From these things, the entire device can be miniaturized. In addition, automation becomes easy and the manufacturing cost is reduced.

[0011]

EXAMPLES The present invention will be described below based on specific examples. FIG. 1 is a schematic configuration sectional view of a hybrid integrated circuit device (hereinafter referred to as HIC) 100 which is a fuel pump controller (hereinafter referred to as FPC) to which the present invention is applied. Note that FIG. 2A is a sectional view of a top view of the appearance of the entire HIC 100, and FIG. 2B is a vertical sectional view thereof (however, the heat radiation fin 9 is not shown). In the HIC 100, the circuit board 6 is adhered and fixed to the aluminum heat dissipation plate 1 (hereinafter referred to as an aluminum plate) which is a heat dissipation plate with the adhesive 5. Then, the bonding surface 8 of the protrusion 2 of the aluminum plate 1 is bonded by the bonding wire 3.
And the aluminum pad 4 which is an electrode of the circuit board 6 are bonded so that the aluminum plate 1 and the GND of the circuit board 6 can be grounded. The aluminum plate 1 has a circuit board 6 sealed with an adhesive 5 in an insert-molded resin case 7 (hereinafter referred to as a case) which is a case. Further, in FIG. 1, in order to further improve the heat dissipation characteristics, a structure in which the heat dissipation fin 9 is fixed by a screw 10 (not shown) is additionally shown (not shown in FIG. 2). Further, in some cases, the circuit board 6 may be filled with the gel filler 12 for waterproofing or the like.

In addition, the portion where the aluminum plate 1 is bonded to the housing 7 is provided with a recess 11 at the edge portion of the housing 7 so that the adhesive 5 does not stick out between the housing 7 and the aluminum plate 1. The adhesive 5 that protrudes does not swell or drip outside the housing 7. If the concave portion 11 is not formed, the aluminum plate 1 is pressed when the aluminum plate 1 is attached to the housing 7, and the adhesive 5 always squeezes out even a little, so that the adhesive 5 swells more than the outer shape of the housing 7. It sticks. This is not good in appearance and may cause troubles during assembly.

The protrusion 2 of the aluminum plate 1 is, for example, when the aluminum plate 1 is punched out from a large aluminum plate by a press.
At the same time, it is formed by punching (pressing) from the position on the back side of the protrusion 2 of the aluminum plate, and the bonding surface 8 is chamfered. In addition, as shown in FIG. 5, the protrusions 2 may be formed by aluminum die casting, and the bonding surface 8 may be chamfered. In the case of directly bonding on the circuit board 6 side, the height of the protrusion 2 is preferably about the thickness of this board (about 0.8 mm), and the Al pad 4 (Ni plating or Ni plating) for bonding on the circuit board 6 side is desirable. When mounting a metal pad (clad with aluminum) and bonding on it, it is sufficient if the height (about 0.5 mm) is added. Any forming method may be used as long as the bonding surface 8 capable of performing reliable bonding can be secured. In addition, it is easy to implement a punched shape that is round (circular). In the case of a polygon, the ratio of stress applied to the corners increases, and when the adhesive adheres, the adhesive concentrates on the corners due to surface tension,
It is not desirable because it is more likely to climb onto the bonding surface. In addition, since it is sufficient if the area is such that bonding can be easily performed, it is preferable to set it to about φ2 mm. In addition, if it is this degree, a press type can be sufficiently used.

In wire bonding between the bonding surface 8 of the protrusion 2 and the aluminum pad 4 which is an electrode of the circuit board 6, the bonding height is formed to be substantially the same on both sides. The adhesive 5 for bonding 6 to the aluminum plate 1 does not protrude to the bonding surface 8,
It can be located near the edge of the circuit board 6 (see 2, 3, and 03 in FIG. 3), and a clean bonding surface is maintained, so that reliable bonding can be performed. Therefore, there is no risk of the wires coming into contact with the edge portion of the circuit board 6, and it is possible to suppress the occurrence of defects. Also, the stress applied to the wire is slightly reduced. Further, the heights being substantially the same may be the same under the bonding conditions because of the bonding tool, which improves workability. FIG. 4 is a top view of this bonding structure, and the outer peripheral frame in the figure is the inner peripheral portion of the casing 7 not shown. 4, 2, 3 and 4 of the present invention are comparatively compact, and compared with the conventional configuration shown in 03 and 04 of FIG. 4, the aluminum plate 1 does not occupy the area and wire bonding is more compact. .

The aluminum plate 1 is also fixed to the end surface of the housing 7 with the adhesive 5. For the purpose of downsizing the entire device, there is a method in which the bonding surface is made larger inside the housing without enlarging the outer dimensions, but it cannot be unnecessarily increased because the internal mounting volume is reduced. Therefore, the surface tension of the adhesive is used to make recesses in the edges (corners) of the adhesive surface against which the aluminum plate 1 on the outside of the housing abuts, so that the adhesive can better fit where it should not stick out. A recess 11) is provided. On the inner side of the bonding surface of the housing, the adhesive intentionally overflows from the housing,
The surface tension forms a fillet so that the adhesive creepage distance is increased. For example, if the width of the adhesive surface is about 3 mm,
It is preferable that the concave portion 11 has a radius of 0.5 to 1.0 mm, a taper, a notch, or a step.

The aluminum plate 1 does not have to be fitted into the housing 7 for the purpose of automating the assembling process.
A mounting boss (not shown) on the side of the housing 7 fits into a positioning hole (not shown) provided in, and is fixed at a predetermined position and bonded. Aluminum plate with HIC 1
On the other hand, the adhesive surface is compressed while applying pressure to the housing 7, but the applied adhesive is crushed and tends to protrude from the contact surface. However, the adhesive 5 does not accumulate in the recess 11 (R-shaped) provided on the outer side of the end surface of the housing 7 and does not pop out of the housing or flow out and drip. For this reason, the aluminum plate 1 is covered with a metal cover from above the housing.
The external adhesive 5 does not get caught when it is fixed on the side, and the appearance is good.

Further, it is efficient to form the aluminum plate 1 by punching as described above, but at the time of punching, the end surface of the plate slightly sags, and the aluminum plate 1 is slightly rounded. Since a state in which the adhesive 5 is attached is provided, if this is made to correspond to the concave portion of the adhesive surface, it is more effective to suppress the protrusion of the adhesive 5.

As a modification of the shape of the recess for accommodating the adhesive, the shape shown in FIG. 6 has the same effect. Figure 6
(a) shows the case where a recess is formed on the C-cut surface.
(b) shows the case where a recess is formed by a notch or a step. Although not shown, a recess may be provided at the edge of the inner peripheral surface of the bonding surface of the housing 7 when it is not desired to attach an adhesive fillet to an internal device or the like.

If the size of the aluminum plate 1 is made larger than that of the housing in order to prevent the adhesive 5 from sticking out of the housing (FIG. 7 (b)), the housing of the FPC itself is made larger. As a result, the metal cover to cover from above must be enlarged. This is a disadvantage for the purpose of downsizing.

When the aluminum plate 1, which is a heat dissipation plate, has insufficient heat dissipation characteristics, a heat dissipation fin 9 is fixed to the outside of the aluminum plate 1 by screwing or welding. Since the aluminum plate 1 has a shape corresponding to the lid of the housing 7, the heat radiation fin 9
The heat dissipation characteristics can be satisfied by auxiliaryly mounting with a size suitable for the heat generation condition. Usually, the aluminum plate 1 is provided with a fixing screw hole for a bracket for attaching the FPC to the mounting portion (both the bracket and the screw hole are not shown), and the radiating fin 9 is fixed at a position excluding the bracket attaching region. Let In FIG. 1, the fixing screw of the heat radiation fin is not shown.

The reason why the radiation fin 9 is externally attached according to the type is as follows. When the insert-molded resin case is commonly used according to the type of product, if the control part of the internal circuit is shared and the change is made to the drive element, the heat generated by the drive element of the internal circuit is radiated. The thickness and surface area of the heat sink must be changed according to the amount of heat generated, but the manufacturing process for bonding the heat sink and the circuit board that makes up the internal circuit is a relatively early step in device manufacturing. Therefore, the process is divided according to the type of heat sink, which lowers the productivity. Therefore, by using the basic aluminum plate 1 as a common part, most of the steps can be made common, and the other necessary radiating fins 9 are fixed for each product type. It can be combined with an assembly process.

The radiation fin 9 may be assembled by a screw tightening method, and it is desirable that the radiation fin 9 is fixed by two or more screws.
Alternatively, in the case of a hooking type radiation fin, even one screw can be fixed. At that time, heat dissipation grease may be applied between the aluminum plate 1 and the aluminum plate 1 to enhance the effect. In addition, when attaching the radiation fin 9 with a screw, it is desirable that the thickness of at least the aluminum plate 1 be 2 mm or more, and the screw diameter is practically M3 or more.

When the features claimed in the claims are expressed from the viewpoint of a manufacturing method, they are as follows. That is, (a) in a method for manufacturing a hybrid integrated circuit device in which a metal member also serving as a heat dissipation plate is adhered to the case and a circuit board is sealed in the case, the heat dissipation is performed with an adhesive. Manufacturing of a hybrid integrated circuit device, characterized in that, when a plate is pressed against the housing and adhered, the adhesive protruding to the outer periphery of the housing is contained in a recess provided in the outer peripheral portion of the bonding surface of the housing. Method. (b) In a method of manufacturing a hybrid integrated circuit device, comprising a housing, wherein a metal member also serving as a heat dissipation plate is adhered to the housing to hermetically seal the circuit board in the housing. A hybrid integrated system comprising: a step of fixing a heat sink to the housing with an adhesive; and a step of fixing a heat sink fin having a size corresponding to the amount of heat generated by the circuit board to the outside of the heat sink. Method of manufacturing circuit device. (c) In a method of manufacturing a hybrid integrated circuit device, comprising: a housing, a metal member also serving as a heat sink is adhered to the housing, and a circuit board is hermetically sealed in the housing. A method of manufacturing a hybrid integrated circuit device, wherein the pad portion of the circuit board and the protrusion portion are formed at the same height as the pad portion by stamping from the back side of the heat dissipation plate.

The circuit board referred to in the claims is a board of a hybrid integrated circuit. Further, the casing is not limited to the resin case, and may be made of any material as long as it has a durable structure for sealing the circuit board 6.

As described above, with the configuration according to the present invention,
The FPC can be made smaller than conventional ones, can be easily automated in manufacturing, and reduce the manufacturing cost. Further, the manufacturing cost can be similarly reduced in that the FPC according to the purpose can be manufactured in a common part on the same line.

[Brief description of drawings]

FIG. 1 is a schematic configuration cross-sectional view of a hybrid integrated circuit device (HIC) that is a fuel pump controller.

FIG. 2 is an overall front view and a cross-sectional configuration diagram of a fuel pump controller.

FIG. 3 is an explanatory view of conventional bonding.

FIG. 4 is an explanatory view seen from the upper surface of the bonding of the present invention and the conventional configuration.

FIG. 5 is a schematic configuration diagram of a heat sink made of aluminum die cast.

FIG. 6 is an explanatory view showing another embodiment of the concave portion of the housing adhesion portion.

FIG. 7 is an explanatory view of a conventional case adhesion part.

[Explanation of symbols]

1,01 Aluminum plate (heat sink, metal member) 2 Protrusions 3,03 Bonding wire 4,04 Aluminum pad 5,05 Adhesive 6,06 Circuit board (HIC board) 7,07 Housing (insert molding resin case) 8 Bonding Surface 9 Radiating Fin 11 Recess 12 Filler 100 Hybrid Integrated Circuit Device (HIC, Fuel Pump Controller)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Ando 1-1-1, Showa-cho, Kariya city, Aichi prefecture Nihon Denso Co., Ltd.

Claims (4)

[Claims] 1. A hybrid integrated circuit device comprising a housing, a metal member also serving as a heat dissipation plate bonded to the housing, and a circuit board sealed in the housing, wherein the circuit board of the heat dissipation plate is It has a protrusion on a part of the surface to be bonded, and wire bonding is performed between the pad portion of the circuit board and the upper surface of the protrusion provided at substantially the same height as the pad portion. Characteristic hybrid integrated circuit device. 2. A hybrid integrated circuit device comprising a housing, wherein a metal member also serving as a heat dissipation plate is adhered to the housing and a circuit board is hermetically sealed in the housing. A hybrid integrated circuit device characterized in that a radiation fin having a size corresponding to the amount of heat generated by the circuit board is fixed. 3. A hybrid integrated circuit device comprising a case, wherein a metal member also serving as a heat sink is adhered to the case and a circuit board is hermetically sealed in the case, wherein the case is adhered to the heat sink. A hybrid characterized in that a concave portion is provided at an outer peripheral corner portion of a bonding surface of a body, and an adhesive that is protruded when the heat dissipation plate is adhered to the concave portion is contained and the adhesive does not protrude to the outside of the housing. Integrated circuit device. 4. The hybrid integrated circuit device according to claim 3, wherein the recess is a round chamfer, a C chamfer, a step or a notch.