JPH03263897A - Packaging of hybrid integrated circuit - Google Patents

Abstract

PURPOSE:To prevent a bonding wire from being extended or burnt out on packaging and transmission characteristics from deteriorating greatly by setting a bonding wire connection point on a signal terminal side to a higher position than that on a hybrid integrated circuit side. CONSTITUTION:A dielectric block 16 of a signal terminal 2 is formed thicker than a dielectric substrate 22 of a hybrid integrated circuit. Then, a bonding wire connection point on a side of the signal terminal 2 is set to a higher position than that on the hybrid integrated circuit side.

Description

[Detailed Description of the Invention] Summary Regarding a method for mounting a hybrid integrated circuit, the present invention aims to provide a method for mounting a hybrid integrated circuit in which there is no risk of bonding wires being disconnected during mounting, and in which transmission characteristics are less likely to deteriorate due to wire bonding. A metal package base having a signal terminal formed on the edge thereof, which is made of a dielectric block on which a side microstrip line is formed, is heated, and the integrated circuit side microstrip line is placed on the flat surface of the metal package base. A first step of fixing a hybrid integrated circuit having a dielectric substrate formed with a dielectric substrate with a solder material, and a second step of connecting the +J tube line and the microstrip line on the integrated circuit side by wire bonding. and a third step of reheating the metal package base in this order, wherein the bonding wire connection point on the signal terminal side in the second step is connected to the hybrid integrated circuit. It is configured to be located at a higher position than the bonding wire connection point on the integrated circuit side.

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for mounting a hybrid integrated circuit used in radio equipment in microwave and millimeter wave frequency bands.

In recent years, microwave integrated circuits (MICs) have been widely used in wireless devices in the microwave and millimeter wave frequency bands due to demands for smaller devices, greater versatility, lower prices, higher reliability, etc. It looks like this. Microwave integrated circuits are generally provided as hybrid integrated circuits. Here, a hybrid integrated circuit is a circuit in which active and/or passive elements (passive elements include those made to function by the shape of a conductor pattern) are integrally provided on a dielectric substrate. Refers to parts. When using this type of hybrid integrated circuit, optimization of its mounting method is being sought.

PRIOR ART AND PROBLEMS TO BE SOLVED BY THE INVENTION A conventional method for mounting a hybrid integrated circuit and problems in this method will be explained with reference to FIG. First, as shown in Figure 6(a),
A metal package base 4 having signal terminals 2 provided at its edges is heated, and a hybrid integrated circuit 6 is fixed onto the metal package base 4 with a solder material 8. At this time, the gap between the end of the hybrid integrated circuit 6 and the metal package base 4 varies from 10 to Usually, a gap S of about 30 μm is created. Next, once the metal package base 4 and the like have been cooled to around room temperature, as shown in FIG. 6(b), the terminal side microstrip line on the signal terminal 2 and the integrated circuit side microstrip line on the hybrid integrated circuit 6 are A wire bonding connection is made between the strip line and the strip line using a bonding wire 10. When the metal package base 4 etc. is cooled to about room temperature, the solder material 8 solidifies due to the difference between the temperature at which it solidifies and the room temperature, and the difference between the coefficient of linear thermal expansion of the hybrid integrated circuit 60 and the coefficient of linear thermal expansion of the metal package base 4. As a result, a so-called bimetal effect appears, and the hybrid integrated circuit 6 also curves in the same direction as the metal package base 4, and the deformation of the end portion from the position before the curve becomes ΔS (for example, 20 to 40 μm). At this time, the gap between the end of the hybrid integrated circuit 6 and the metal package base 4 is 82, which is about the same as SI.

By the way, the dielectric substrate that determines the strength characteristics of the hybrid integrated circuit 6 is difficult to be plastically deformed. On the other hand, the metal package base 4 made of oxygen-free copper or the like is easily plastically deformed. Therefore, the internal stress in the state shown in FIG. 6(b) tends to be relaxed over time. However, since this internal stress does not reach zero, for example, in order to fix the lid member of the hermetically sealed sleeve to the metal package base 4 with solder, the metal package base 4 is reheated and the solder is applied. 8
When the metal package base 4 is remelted, the elastically deformed hybrid integrated circuit 6 is restored to its original shape, but the plastic and elastically deformed metal package base 4 is not restored to its original shape. Therefore, when the solder material 8 is remelted, a gap S3 of, for example, about 20 to 60 μm, which is larger than S2, will be created between the end of the hybrid integrated circuit 6 and the metal package base 4. If such a large gap occurs, the bonding wire 10 will stretch, or in the worst case, the bonding wire 10 will break as shown in FIG. 6(C).

In order to prevent the bonding wire from elongating and breaking, it may be proposed to perform wire bonding so that the bonding wire is long in advance, but this may change the characteristic impedance of the transmission line and cause deterioration of high frequency characteristics, etc. be.

The present invention was created in view of these technical problems, and an object of the present invention is to provide a method for mounting a hybrid integrated circuit in which there is no risk of bonding wires being stretched or disconnected during mounting, and in which transmission characteristics are less likely to deteriorate due to wire bonding. The purpose is

Means for Solving the Problems The method of the present invention, which was made in order to solve the above-mentioned technical problems, is a metal package having a signal terminal provided at its edge, which is made of a dielectric block on which a terminal-side microstrip line is formed. a first step of heating the base and fixing the hybrid integrated circuit including the dielectric substrate on which the microstrip line on the integrated circuit side is formed on the flat surface of the metal package base with a solder material; Mounting of a hybrid integrated circuit comprising, in this order, a second step of connecting the terminal side microstrip line and the integrated circuit side microstrip line by wire bonding, and a third step of reheating the metal package base. It applies to methods.

The feature is that the bonding wire connection point on the signal terminal side in the second step is located at a higher position than the bonding wire connection point on the hybrid integrated circuit side.

According to the method of the present invention, wire bonding is performed with the bonding wire connection point on the signal terminal side being located at a higher position than the bonding wire connection point on the hybrid integrated circuit side. Even if the metal package base is reheated and the solder material interposed between the metal package base and the hybrid integrated circuit is remelted and the internal stress is released, each component will not be able to connect to the bonding wire on the signal terminal side. The connection point and the bonding wire connection point on the hybrid integrated circuit side are deformed in a direction closer to each other. Therefore, according to the method of the present invention, elongation and breakage of the bonding wire due to remelting of the solder material can be prevented. In this case, by performing wire bonding in the second step so that the bonding wire has the shortest distance, the bending of the bonding wire after the solder material is remelted will be slight, so there will be little deterioration in transmission characteristics. .

Example Embodiments of the present invention will be explained below based on the drawings.

FIG. 5 is an exploded perspective view of a package that can be used to implement the present invention. This package consists of a metal package base 4 made of oxygen-free copper on which a plurality (six in this example) of signal terminals 2 are provided on the edge, and a metal package base 4 made of oxygen-free copper with a silver It is composed of a metal frame member 12 fixed by low welding, and a metal lid member 14 fixed to the upper end of the metal frame member 12 by soldering.

A flat surface coplanar with the fixing surface of the signal terminal 18 is formed at a position surrounded by each signal terminal 2 on the metal package base 4, and the hybrid integrated circuit 6 is fixed onto this flat surface. . The signal terminal 2 is composed of a dielectric block 16 made of alumina or the like fixed on the metal package base 4, and a terminal-side microstrip line 18 made of a conductive thin film formed on the dielectric block 16. . A notch 20 is formed at the lower end of the metal frame member 12 at a position corresponding to each signal terminal 2, and when joining the metal frame member 12 and the metal package base 4, a glass sealant or the like is placed in the notch 20. By doing so, the joint portion is hermetically sealed and the terminal side microstrip line 18 is insulated.

When mounting the hybrid integrated circuit 6 using this package, the signal terminals 2 are fixed to the metal package base 4 in advance, and the metal frame member work 2 is also joined to the metal package base 4. Then, the hybrid integrated circuit 6 is A u / S
After the first step of fixing the metal package base 4 on the metal package base 4 using a solder material such as n-solder, wire bonding is performed (the second step), and finally each member is heated to form the metal lid member 1.
4 is fixed to the metal frame member 12 by soldering (third step).

FIG. 1 is a diagram for explaining a first embodiment of the present invention, and shows a plan view (a) and a cross-sectional view of the vicinity of a wire bonding portion during wire bonding. In the hybrid integrated circuit 6, 22 is a dielectric substrate fixed to the metal package base 4 with a solder material 8, and 24 is a microstrip line formed on the dielectric substrate 22 on the integrated circuit side. 26 is a notch 20 in the metal frame member and a signal terminal 2
A glass sealant is interposed between the two. In this embodiment, the dielectric block 16 of the signal terminal is formed thicker than the dielectric substrate 22 of the hybrid integrated circuit, so that the bonding wire connection point on the signal terminal side is greater than the bonding wire connection point on the hybrid integrated circuit side. It is also placed in a high position.

In this way, even if the solder material 8 is remelted when the metal lid member 14 is fixed to the metal frame member 12 by soldering, the signal terminals 2 will not be affected by the hybrid integrated circuit 6 due to residual plastic deformation in the metal package base 4. The relative displacement is determined by the signal terminal 2 and the hybrid integrated circuit 6, as shown in FIG.
Since the heights of the bonding wire connection points are aligned in the same direction, it is possible to prevent the bonding wire 10 from being stretched or broken due to undesired stress being applied to the bonding wire 10.

FIG. 2 is a diagram showing a second embodiment. In this example,
The thickness of the signal terminal 2 is the same as the conventional hybrid integrated circuit 6.
By setting the bonding wire connection on the signal terminal side to be equal to the thickness of It is located at a higher position than the bonding wire connection point on the integrated circuit side. In microwave integrated circuits,
It is often necessary to mount a chip capacitor for a DC bias element, and in such cases, if the present invention is implemented as in the second embodiment, it becomes unnecessary to mount a chip capacitor on the hybrid integrated circuit 6. Therefore, the exclusive mounting area on the dielectric substrate 22 is expanded, and designability and manufacturability are improved.

Furthermore, according to the second embodiment, the members used in the conventional method can be used as they are.

FIG. 3 is a diagram showing a third embodiment of the present invention.

In this embodiment, a metal block 30 having the same size and shape as the chip capacitor 28 is used in place of the chip capacitor 28 in the second embodiment. In this case, the bonding wire connection point on the signal terminal side can be placed at a higher position than the bonding wire connection point on the hybrid integrated circuit side during wire bonding, so stretching and disconnection of the bonding wire can be prevented. It can be prevented. In the third embodiment as well, members such as signal terminals used in the conventional method can be used as they are.

In the first to third embodiments, by performing wire bonding so that the bonding wire is as short as possible, the bending of the bonding wire in the final form is slight, so there is little deterioration in transmission characteristics. That is, in the conventional method, when wire bonding is performed by bending the bonding wire in advance to prevent the bonding wire from elongating or breaking, it is necessary to bend the bonding wire in advance so that the bending of the bonding wire in the final form is slight. Considering the fact that it is difficult to specify the bending of the bonding wire in advance, the bending of the bonding wire in the final form is kept to a slight level as in the first to third embodiments. This is effective in minimizing deterioration of transmission characteristics.

As described in detail, the present invention provides a method for mounting a hybrid integrated circuit in which there is no risk of bonding wires being stretched or disconnected during mounting, and the transmission characteristics are less likely to deteriorate due to wire bonding. play.

[Brief explanation of drawings]

1 is a diagram showing a first embodiment of the present invention, FIG. 2 is a diagram showing a second embodiment of the present invention, FIG. 3 is a diagram showing a third embodiment of the present invention, and FIG. 4 is a diagram showing the present invention. FIG. 5 is an exploded perspective view of a package that can be used to implement the present invention. FIG. 6 is an explanatory diagram of the prior art. 2... Signal terminal, 4... Metal package base, 6... Hybrid integrated circuit, 8... Solder material, 16... Dielectric block, 18... Terminal side microstrip line, 22 ...
Dielectric substrate, 24... Integrated circuit side microstrip line, 28...
...Chip capacitor, 30...Metal block.

Claims (4)

[Claims] 1. Heating a metal package base (4) on which a signal terminal (2) consisting of a dielectric block (16) on which a terminal-side microstrip line (18) is formed is provided at the edge;
A hybrid integrated circuit (6) comprising a dielectric substrate (22) on which an integrated circuit side microstrip line (24) is formed is placed on the flat surface of the metal package base (4) using a solder material (8).
a second step of connecting the terminal-side microstrip line (18) and the integrated circuit-side microstrip line (24) by wire bonding; and a second step of bonding the metal package base (4). and a third step of reheating in this order, wherein the bonding wire connection point on the signal terminal (2) side in the second step is on the hybrid integrated circuit (6) side. A method for mounting a hybrid integrated circuit, characterized in that the bonding wire is located at a higher position than the connection point. 2. The dielectric block (16) and the dielectric substrate (
22) is fixed on the same plane on the metal package base (4), and by forming the dielectric block (16) thicker than the dielectric substrate (22), the second
2. The hybrid device according to claim 1, wherein the bonding wire connection point on the signal terminal (2) side in the step is located at a higher position than the bonding wire connection point on the hybrid integrated circuit (6) side. How to implement integrated circuits. 3. By making the bonding wire connection on the signal terminal (2) side via a chip capacitor (28) provided on the terminal side microstrip line (18), the signal terminal (2) in the second step is made. 2. The method of mounting a hybrid integrated circuit according to claim 1, wherein the bonding wire connection point on the side of the hybrid integrated circuit (6) is located at a higher position than the bonding wire connection point on the hybrid integrated circuit (6) side. 4. By making the bonding wire connection on the signal terminal (2) side via the metal block (30) provided on the terminal side microstrip line (18),
2. The method according to claim 1, wherein the bonding wire connection point on the signal terminal (2) side in the second step is located at a higher position than the bonding wire connection point on the hybrid integrated circuit (6) side. A method of implementing the described hybrid integrated circuit.