JPH0364052A - Hybrid integrated circuit - Google Patents

Abstract

PURPOSE:To improve the strength of a terminal by fixing a lead to a terminal fitting part which is provided at the principal plane of a board through a junction material and coating the periphery of the terminal fitting part with a peeling inhibit coating film. CONSTITUTION:The lead 4 of a hybrid integrated circuit device is fixed to a terminal fitting part 3 in which the fitting part 5 of an inner end is rectangular through a junction material 6 consisting of solder. The periphery of the terminal fitting part 3 is covered with a peeling inhibit coating film 13. Its film 13 is formed by a glass coating film so as to protect the wiring layer 2 and resistance of a principal plane of a wiring board 1. A junction strength to the wiring board 1 at the terminal fitting part 3 becomes strong by the peeling inhibit coating film 13.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a technology that is effective when applied to a hybrid integrated circuit device, particularly to a bonding structure between a wiring board and a lead serving as an external terminal.

[Conventional technology]

Hybrid integrated circuit devices are widely used because they have a structure suitable for multiple functions and high density. The standard manufacturing method for hybrid integrated circuit devices is described, for example, in "Hybrid IC Guide" published by the Japan Electronics Industry Association, July 2, 1988.
Published on the 1st, as described on pages 8 to 9, conductor printing and firing, resistance printing and firing, overcoat glass, Gui bonding, wire bonding, resin coating, component mounting, external lead attachment, and exterior resin sealing. It is manufactured by repeating the steps one after another.

On the other hand, in "Electronic Materials J, May 19B5 issue, published May 1, 1985, pages 162 to 167, published by Kogyo Research Association,
A hybrid IC for mobile radio communication is described as a high frequency, high output hybrid IC. This document describes the need to pay attention to impedance matching in circuit design.

[Problem to be solved by the invention]

In a hybrid integrated circuit device, the wiring layer of the wiring board and the external terminals (leads) are connected using a structure in which the leads are stacked and fixed using a bonding material such as solder to the terminal mounting part provided on one side of the wiring board. Alternatively, a structure in which a lead having a clamp portion at the negative end is clamped to a wiring board and fixed with a bonding material such as solder is often used. In high-frequency, high-output hybrid ICs, a structure is adopted in which the leads are stacked and fixed on one surface of a wiring board in order to achieve impedance matching.

When the hybrid IC for mobile radio communication is used in a wireless key station, its operation frequency is much higher than that in a vehicle, and therefore a product with higher reliability is desired.

In order to improve the characteristics of hybrid integrated circuit devices that operate frequently, temperature cycle tests (-5
5'c to +150°C) and a peeling test was performed, and a failure mode was discovered in which the terminal attachment part peeled off from the wiring board. FIG. 9 is a schematic diagram showing a state in which the terminal mounting portion is peeled off by applying a peeling force to the lead connected to the terminal mounting portion. That is, a wiring layer 2 is provided on the main surface of the wiring board 1, and a portion of this wiring layer 2 that reaches the end of the wiring A base Fi1 is a rectangular terminal attachment portion 3. A rectangular attachment portion 5 at the tip of the lead 4 is fixed to the terminal attachment portion 3 via a bonding material 6 made of solder. Since the wiring board 1 is made of a ceramic board, its coefficient of thermal expansion is 6 to 7X10.
-'/"C. On the other hand, since the terminal mounting part 3 is made of copper, its thermal expansion coefficient is 16~f8X
10-''/'C, and the thermal expansion coefficients of both are partially different.

On the other hand, since the leads 4 and the terminal attachment part 3 are joined by solder with a strong bonding strength, there is almost no possibility that the two will peel off due to thermal stress. Since it is formed by printing a conductor on the surface and firing it, the bonding strength between the two is not necessarily high, and the bonding strength at the bonding interface decreases due to thermal stress generated in the terminal mounting portion 3, resulting in beer vibration. By testing,
As shown in FIG. 9, the terminal mounting portion 3 peels off from the wiring board 1.

An object of the present invention is to provide a highly reliable hybrid integrated circuit device with high terminal strength.

The above and other objects and novel features of the present invention include:
It will become clear from the description of this specification and the accompanying drawings.

[Means to solve the problem]

A brief overview of typical inventions disclosed in this application is as follows.

That is, the hybrid integrated circuit device of the present invention has a structure in which the leads are fixed to the terminal mounting portions provided on the main surface of the wiring board via the bonding material. Further, the periphery of the terminal attachment portion is covered with a peeling prevention coating film.

[Operation] According to the above-described means, the hybrid integrated circuit device of the present invention has the following features:
The structure is such that the leads are fixed to the terminal mounting portion provided on the main surface of the wiring board via a bonding material, but since the periphery of the terminal mounting portion is covered with a peeling prevention coating film, the terminal The attachment portion is firmly fixed to the wiring board, and even if thermal stress acts on the terminal attachment portion in a temperature cycle test, the terminal attachment portion is difficult to separate from the wiring board.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic plan view showing a terminal mounting part in a hybrid integrated circuit device according to an embodiment of the present invention, FIG. 2 is a sectional view of the same, and FIG. 3 is an external view of the hybrid integrated circuit device of the present invention. FIG. 4 is a flowchart showing the manufacturing of the hybrid integrated circuit device of the present invention, FIG. 5 is a plan view showing a part of the wiring board on which the wiring layer is formed, and FIG. FIG. 7 is a plan view showing a part of the wiring board on which a coat film is formed, and FIG. 7 is a plan view showing a part of the wiring board to which leads are similarly bonded.

As shown in FIG. 3, the hybrid integrated circuit device of this embodiment has a header 10 made of a metal having good thermal conductivity, such as a copper plate, and a header 10 that is superimposed on the main surface of the header 10. A wiring board 1 made of a ceramic board as shown in FIG. It consists of The header 10 is
Although not particularly limited, the thickness is 2.3 mm, and the wiring board 1 has a thickness of about 0.6 mm.

Further, the sealing case 11 is made of plastic, and is bonded to the wiring board l with an adhesive made of silicone resin (not shown). Further, the portions of the header 10 that protrude from both ends of the sealing case 11 are provided with mounting grooves 12 that are used when mounting this hybrid integrated circuit device. Passive components such as resistors and capacitors and active components such as power semiconductor elements are mounted inside the sealing case 11, and a desired circuit is formed by the wiring layer 2 provided on the main surface of the wiring board l. is forming.

In such a hybrid integrated circuit device, the mounting portion 5 at the inner end of the lead 4 is fixed to a rectangular terminal mounting portion 3 as shown in FIG. 1 via a bonding material 6 made of solder. The dimensions of the wiring 112, the terminal attachment portion 3, and the lead 4 are selected to provide a desired impedance. For example, the width of the wiring layer 2 is 1 mm or less, the terminal attachment part 3 is a square with a side of 1.5 mm, the thickness of the lead 4 is 0°25 mm, the width of the lead 4 is 0.45 mm, and the attachment part 5 of the lead 4 is a square with sides of 1 mm.

Furthermore, this is one of the characteristics of the present invention, and the periphery of the terminal attachment part 3 to which the attachment part 5 of the lead 4 is attached is as conceptually shown in FIGS. 1 and 2. It is covered with a peeling prevention coat 113 (hatched area).

This peeling prevention coat 11113 is formed of a glass coating film several tens of pm thick that is coated to protect the wiring layer 2 and the resistor (thick film resistor) on the main surface of the wiring board l. This peeling prevention coating film 13
As a result, the peripheral edge of the terminal mounting portion 3 is fixed to the wiring board 1, and as a result, the bonding force of the terminal mounting portion 3 to the wiring board l becomes large. Therefore, the helada 10 (thermal expansion coefficient 16
~18x10-'1/'C) and arrangement! ! Even if the thermal expansion coefficients of the substrates 1 (thermal expansion coefficients 6 to 7X10-'1/'C) are significantly different from each other by one order of magnitude, and the bonding strength is slightly reduced due to repeated thermal stress between the two, the peeling will not occur. Due to the covering effect of the deterrent coating film 13, the terminal mounting portion 3 is prevented from peeling off from the wiring board 1.

Further, the peeling prevention coat 1113 is provided all around the terminal mounting portion 3, and since the solder that is the bonding material 6 does not get wet with the peeling prevention coating film 13 that is glass, the bonding material 6 does not prevent this peeling. Deterrent coat I! It swells inside 13.

Therefore, the attachment part 5 of the lead 4 is fixed by the surface tension of the solder so that its center is aligned with the center of the terminal attachment part 3.
The accuracy of attaching the lead 4 is improved. Further, since the bonding material 6 does not overflow from the peeling prevention coat film 13, not only does the defect in which the bonding material 6 flows out from the green part of the wiring board 1 occur, but also the bonding material 6 that fixes the mounting portion 5 of the lead 4 does not overflow. The thickness is also constant, and the bonding performance is stable.

Next, the manufacturing of such hybrid integrated circuit devices, especially the peeling and pressing method)! The manufacturing method of 1113 will be explained.

The hybrid integrated circuit device is manufactured through each work process shown in the flowchart of FIG. First, a patterned ceramic plate having through holes, hollowed out parts, etc. is prepared. Thereafter, as shown in FIG. 5, a conductor is printed in a desired pattern on the surface of the ceramic plate 14 by a commonly used printing method and fired, thereby forming a wiring layer 2, a rectangular terminal mounting portion 3, etc. It is formed. Further, on the surface of the ceramic plate 14, a resistor is printed in a desired pattern (not shown) using a commonly used printing method and then fired. The resistor is trimmed as necessary to a desired resistance value.

Next, as shown by the hatched area in FIG. 6, a glass coating is applied to desired portions of the ceramic plate 14 to form an overcoat glass film 15. As a result, the ceramic board 14 becomes the wiring board 1. The overcoat glass film 15 is provided to cover the resistor, wiring layer 2, etc.

For example, when a chip resistor is mounted between adjacent wiring layers 2, the overcoat glass film 15 is not provided in the resistor mounting area 16 of the wiring layer 2, as shown in FIG. During this glass coating, the periphery of the terminal mounting portion 3 is coated, and the overcoat glass film 1
5 is formed.

Next, such a wiring board 1 is overlaid and fixed on the main surface of the ladder 10 by soldering or the like. after that,
Chimp bonding and wire bonding are performed.

In addition, chips, wires, etc. are coated with resin (undercoat resin) to protect them. Also, the seventh
As shown in the figure, a chip resistor 17 is connected to the solder 1 shown in dots over the adjacent terminal mounting portions 3 of the wiring board II.
It is mounted (components are mounted) through 8.

Next, as shown in FIG. 7, the mounting portions 5 of the leads 4 are fixed to each terminal mounting portion 3 of the wiring board 1 via a bonding material 6 made of solder. At this time, as mentioned above, since the terminal mounting part 3 is covered with the peeling prevention coating film 13 that does not wet the solder, the mounting part 5 is positioned and fixed with high precision by the surface tension of the solder. . Further, the bonding material 6 to be fixed is determined.

Next, a sealing case 11 is attached to the main surface side of the wiring board 1 for packaging, and a hybrid integrated circuit device is manufactured.

According to such an embodiment, the following effects can be obtained.

(1) In the hybrid integrated circuit device of the present invention, the periphery of the terminal mounting portion of the wiring layer provided on the wiring board is covered with a peeling prevention coating film, so that the bonding force of the terminal mounting portion to the wiring board is reduced. Since the overall size is larger than that of the conventional wiring board, even if repeated thermal stress occurs due to the difference in coefficient of thermal expansion between the wiring board made of a ceramic plate and the terminal mounting part made of metal, the terminal mounting part will still be attached to the wiring board. There is no possibility that the terminal will peel off from the terminal, and the reliability of supporting the terminal mounting portion will be improved.

(2) According to (1) above, in the hybrid integrated circuit device of the present invention, the periphery of the terminal mounting portion is covered with a peeling-preventing coating film made of glass, so that when manufacturing the hybrid integrated circuit device, the peeling Since the deterrent coating film acts as a dam to prevent solder from flowing out, a certain amount of solder is contained within a certain area, and the thickness of the solder bonding layer remains constant, resulting in stable bonding reliability. can get.

(3) According to (2) above, in the hybrid integrated circuit device of the present invention, since the periphery of the terminal mounting portion is covered with a peeling prevention coating film made of glass, melting may occur during manufacturing of the hybrid integrated circuit device. Since the solder is contained within the peel-off prevention coating film, the rectangular mounting part that rests on the melted solder is always centered in the center due to the surface tension of the solder, resulting in the effect that the lead bonding position remains constant. .

(4) According to (1) above, in the hybrid integrated circuit device of the present invention, since the periphery of the terminal attachment portion is covered with a peeling-preventing coating film made of glass, the peeling-off prevention coating film is not removed during manufacturing of the hybrid integrated circuit device. Since the inhibitory coating film acts as a dam to prevent solder from flowing out, the solder does not overflow from the peeling prevention coating film, thereby preventing defects in which solder protrudes from outside the edge of the wiring board (5) (5). According to 1), in the hybrid integrated circuit device of the present invention, since the periphery of the terminal mounting portion is covered with a peeling prevention coating film made of glass, the peeling prevention coating film is not soldered when manufacturing the hybrid integrated circuit device. Since the solder acts as a dam to prevent outflow, the solder does not overflow from the peeling prevention coating film, resulting in the effect that the lead pitch can be made smaller.

(6) According to the above (1) to (5), according to the present invention, a synergistic effect can be obtained in that a highly reliable hybrid integrated circuit device with high lead bonding strength can be provided.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the above Examples and can be modified in various ways without departing from the gist thereof. For example, as shown in FIG. 8, if the purpose is only to increase the bonding strength of the terminal attachment part 3 to the wiring board l, the edge of the peeling prevention cord, that is, the edge near the outer end of the lead. It may be provided at the edge portion, and the same effect as in the previous embodiment can be obtained.

In the above description, the invention made by the present inventor is mainly applied to the technology for manufacturing hybrid integrated circuit devices, which is the background field of application, but the invention is not limited thereto.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

The hybrid integrated circuit device of the present invention has a structure in which the leads are fixed to the terminal mounting portion provided on the main surface of the wiring board via a bonding material, and the periphery of the terminal mounting portion is coated with a peeling prevention coating. Because the terminal mounting part is covered with Become. Therefore, the reliability of lead bonding is improved, and the reliability of the hybrid integrated circuit device is increased.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing a terminal attachment part in a hybrid integrated circuit device according to an embodiment of the present invention, FIG. 2 is a sectional view of the same, and FIG. 3 is an external view of the hybrid integrated circuit device of the present invention. 4 is a flowchart showing the manufacturing of the hybrid integrated circuit device of the present invention. FIG. 5 is a plan view showing a part of the wiring board on which the wiring layer is formed. FIG. 6 is the same as the peeling prevention coat. FIG. 7 is a plan view showing a part of the wiring board on which the film is formed; FIG. 7 is a plan view showing a part of the wiring board to which leads are also bonded; FIG. 8 is a terminal mounting portion according to another embodiment of the present invention. FIG. 9 is a schematic diagram showing a state in which the terminal mounting portion is HM by applying a peeling force to the lead connected to the terminal mounting portion. DESCRIPTION OF SYMBOLS 1... Wiring board, 2... Wiring layer, 3... Terminal mounting part, 4... Lead, 5... Mounting part, 6... Bonding material, 10... Header, 11...・・Sealed case, 12・・
・Mounting groove, 13... Peeling prevention coat film, 14... Ceramic plate, 15... Overcoat glass film, 16.
...Resistor mounting area, 17...Chip resistor, 18...
solder. Fig. 1 F13 Fig. 11 J”li, case 13-5-ri S armor upper coat crotch No. 4 Fig. 2-Kokuotsu a4 3-4J 閁I=rn Fig. Fig. 13-!t, J tooth-L main IF2 coat armpit 15-overcoat T-last dark

Claims (1)

[Claims] 1. A hybrid integrated circuit device comprising a wiring board, a wiring layer provided on the surface of the wiring board, and a lead connected to a terminal mounting part of the wiring layer via a bonding material, the terminal mounting part A hybrid integrated circuit device, characterized in that at least one peripheral edge of the hybrid integrated circuit device is covered with a peel-off prevention coating film.