JP2778943B2 - Microwave substrate and microwave package using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave substrate on which electric components constituting a microwave power amplifier and the like are mounted, and a microwave package using the same.

[0002]

2. Description of the Related Art Conventionally, components used for mobile communication devices such as a simple portable telephone (PHS) are required to have conditions such as small size, light weight, low cost, and excellent mass productivity.
In order to satisfy such conditions, a microwave substrate having a metal film formed on a surface of a dielectric substrate and a microwave package using the same have been used.

Here, a conventional microwave package using a metal substrate formed on a surface of a dielectric substrate as a base plate will be described with reference to a perspective view of FIG. 5 taking a leadless type as an example. In FIG. 5, a lid that covers the upper part is omitted for convenience of explanation.

[0005] Reference numeral 51 denotes a dielectric substrate constituting a base plate, and a metal film 52 for mounting electric components is provided on the upper surface.
However, a metal film (not shown) forming a ground plane is formed on the lower surface. Metal film 5 on top of dielectric substrate 51
2 and the metal film on the lower surface are electrically connected by a large number of through holes formed in the dielectric substrate 51. An electric component 53 such as a semiconductor chip, an MIC substrate, or a capacitor is mounted on the metal film 52 on the upper surface of the dielectric substrate 51, and these electric components 53 are bonded to each other or between the electric component 53 and the metal film 52 as appropriate. You.

Reference numerals 54 and 55 denote two-layer frames formed around a base plate formed of the dielectric substrate 51 and the like. A plurality of grooves 56a to 56d having a semicircular cross section are formed outside the side wall portion A formed by the dielectric substrate 51 and the frame 54, and a metal film is formed on the surface thereof. A plurality of grooves 56e to 56h having a semicircular cross section are also formed outside the side wall portion B facing the side wall portion A, and a metal film is formed on the surface thereof. However, these grooves 56e to 56h are not shown because they are on the back side of the side wall portion B.

Further, connection patterns 57e to 57h are formed on the inner surface of the side wall portion B constituted by the frame 54. Connection patterns 57a to 57d are also formed on the inner surface of the frame 54 in the side wall portion A. In this case, the connection patterns 57h, 57a to 57d are not shown in the drawing. Then, a plurality of grooves 56a to 56d, 56e to 56h provided outside the frame 54
And connection patterns 57a-
57d and 57e to 25h are electrically connected, and serve as signal terminals connecting the inside and outside of the frames 54 and 55.
Note that a microwave package is formed by covering the openings above the frames 54 and 55 with a lid formed by plating the surface of the dielectric substrate or a lid formed of a metal plate.

[0007]

The above-mentioned microwave package and the microwave substrate constituting the microwave package are required to be small, light, low in cost, and mass-producible. For this reason, when mounting an electric component such as a semiconductor chip, reflow is performed, and an auto bonder is used for bonding. When the auto bonder is used as described above, it is necessary to accurately mount an electric component such as a semiconductor chip at a correct position.

In the case of a conventional microwave package or microwave substrate, a metal film is formed uniformly on the surface of a dielectric substrate constituting a base plate, and there is no target for mounting an electric component. For this reason, it is difficult to mount the electric component at a correct position. In addition, if the amount of solder for fixing the electric component is large, the electric component floats and may be displaced. Further, the solder may flow out to an unnecessary area on the metal film, and the flowed solder may interfere with bonding of the electric component to the metal film on the dielectric substrate.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks, and provides a microwave substrate on which electric components can be mounted at a correct position on a metal film of a dielectric substrate constituting a base plate, and a microwave package using the same. The purpose is to:

[0010]

SUMMARY OF THE INVENTION The present invention, a metal film on the top surface of the dielectric substrate, forming a metal film forming the ground plane on the bottom surface, electrically the upper and lower surfaces of the metal film in a plurality of through-holes In the microwave substrate connected to the substrate, a part of the metal film formed on the upper surface of the dielectric substrate is removed to form a pattern exposing the dielectric substrate.

Further, the present invention is a metal on the top surface of the dielectric substrate
In a microwave substrate in which a film is formed on the lower surface thereof as a metal film constituting a ground plane and the upper and lower metal films are electrically connected by a plurality of through holes, the metal film formed on the upper surface of the dielectric substrate A part of the electric component mounted on the metal film of the dielectric substrate is overlapped, or at a position in contact with the edge of the electric component mounted on the metal film of the dielectric substrate, The dielectric substrate has an exposed pattern.

Further, the microwave package of the present invention comprises:
A frame is formed at a predetermined height around the upper surface of the dielectric substrate on which the metal film forming the microwave substrate is formed, and signal terminals for connecting the inside and the outside of the frame are formed.

Further, a pattern in which the dielectric substrate is exposed is formed at a plurality of locations.

According to the above configuration, a part of the metal film on the dielectric substrate constituting the microwave substrate is removed, and a pattern exposing the dielectric substrate is formed. Therefore, the electric component can be mounted at a correct position with the target of the pattern where the dielectric substrate is exposed. In addition, the pattern in which the dielectric substrate is exposed makes it difficult for the solder to flow, thereby reducing the displacement of the electric component. In addition, since the solder does not flow into an unnecessary area, bonding between the electric component and the metal film is facilitated.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the perspective view of FIG. Reference numeral 11 denotes a dielectric substrate constituting a base plate, on the upper surface of which a metal film 12 for mounting electric components is formed, and on the lower surface, a metal film (not shown) constituting a ground plane. The metal film 12 formed on the upper surface of the dielectric substrate 11 and the metal film on the lower surface are formed by a large number of through holes (not shown) formed in the dielectric substrate 11.
Are electrically connected by

The metal film 12 on the upper surface of the dielectric substrate 11
For example, a plurality of patterns 13a to 13h, in which portions corresponding to four corners of a rectangle are removed in an L shape and the dielectric substrate 11 is exposed,
13d is formed. Therefore, when the electric component 14 such as a semiconductor chip having a rectangular shape is mounted on the metal film 12, the electric component 14 is arranged such that the outer edge thereof coincides with the inner edge of the patterns 13a to 13d, for example. By targeting the plurality of patterns 13a to 13d in this way, the electric component 14 can be mounted at a correct position.
Then, in this state, the electric components 14 are soldered, and thereafter, the electric components 14 are
And the metal film 12 are bonded.

Reference numerals 15 and 16 represent the dielectric substrate 11.
It is a frame composed of two layers around a base plate composed of, for example. A plurality of grooves 17a to 17d having a semicircular cross section are formed outside one side wall portion A composed of the dielectric substrate 11 portion and the frame 15 portion,
A metal film is formed on the surface. A plurality of grooves 1 having a semicircular cross section also on the outer side of the side wall portion B facing the side wall portion A.
7e to 17h are formed, and a metal film is formed on the surface. However, the plurality of grooves 17e to 17h are
It is not shown in the figure because it is on the reverse side.

Further, connection patterns 18e to 18h are formed on the inner surface of the side wall portion B of the frame 15.
Further, the connection patterns 18a to 18a are also provided on the inner surface of the side wall portion A.
18d are formed. However, connection pattern 18
h, 18a to 18d are not shown in relation to the drawings.
The plurality of grooves 17 provided outside the frame 15
The connection patterns 18a to 18d and 18e to 18h provided inside the frame 15 are electrically connected to the connection patterns a to 17d and 17e to 17h, and serve as signal terminals connecting the inside and outside of the frames 15 and 16. The openings above the frames 15 and 16 are covered with a lid having a surface plated with a dielectric substrate or a lid made of a metal plate, thereby forming a microwave package.

Here, a pattern in which the dielectric substrate is exposed on the base plate will be described with reference to FIG. Reference numerals 21a to 21d denote, for example, a plurality of patterns in which portions corresponding to four corners of a rectangle are removed in an L-shape and the dielectric substrate is exposed. The electric component is mounted in the region 22 indicated by. FIG. 3 shows another example of a pattern in which the dielectric substrate is exposed. In this case, the pattern 31 has a rectangular width. Then, the electric component is mounted in the hatched area 32 inside the pattern 31.
In this case, since the periphery is surrounded by the pattern 31, the flow of the solder is reduced. FIG. 4 shows another example of a pattern in which the dielectric substrate is exposed. Of the four corners of the rectangle, square patterns 41a and 41b having a small area are formed at two diagonally located positions. The electric component is mounted in the area 42 indicated by. In FIGS. 2 to 4, the electric components are mounted along the inside of the pattern where the dielectric substrate is exposed. However, mounting may be performed such that the pattern exposing the dielectric substrate overlaps the back surface of the electric component. In this case, when the electric component is mounted along the inside of the pattern where the dielectric substrate is exposed, the back surface of the electric component to be soldered becomes wider, and the fixing of the electric component and the metal film becomes stronger.

According to the above configuration, the metal film on the base plate surface is removed, and the pattern where the dielectric substrate is exposed can be targeted, so that the electric component can be mounted at a correct position. Further, since the outflow of solder is suppressed by the presence of the pattern in which the dielectric substrate is exposed, displacement of the electric component is reduced, and there is no hindrance to the bonding between the electric component and the metal film.

The above embodiment is an example of a microwave package, but can be applied to a microwave substrate having no surrounding frame. In addition, the number of patterns where the dielectric substrate is exposed may be singular or plural, but positioning is easier if a plurality of patterns are provided for one electric component. Moreover, the shape of the pattern exposing the dielectric substrate may be triangular or
A person with a corner, such as a square, can target that corner,
The positioning of the electric components becomes easy.

[0022]

According to the present invention, a microwave substrate or a microwave package on which electric components can be mounted at a correct position can be realized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a diagram illustrating a pattern in which a dielectric substrate used in the present invention is exposed.

FIG. 3 is a diagram illustrating another example of a pattern in which a dielectric substrate used in the present invention is exposed.

FIG. 4 is a diagram illustrating another example of a pattern in which a dielectric substrate used in the present invention is exposed.

FIG. 5 is a perspective view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Dielectric substrate 12 ... Metal film 13a-13d ... Pattern which exposed the dielectric substrate 14 ... Electric parts 15, 16 ... Frame 17a-17d ... Multiple groove | channels 18e-18g ... Connection pattern

Claims (4)

(57) [Claims] 1. A contact on the top surface of the dielectric substrate to the metal film, the lower surface
In a microwave substrate in which a metal film constituting the ground is formed and the upper and lower metal films are electrically connected by a plurality of through holes, a part of the metal film formed on the upper surface of the dielectric substrate is removed. A microwave substrate having a pattern in which the dielectric substrate is exposed. Wherein the metal film on the top surface of the dielectric substrate, against the lower surface
In a microwave substrate in which a metal film constituting the ground is formed and the upper and lower metal films are electrically connected by a plurality of through holes, a part of the metal film formed on the upper surface of the dielectric substrate is removed. The dielectric substrate is exposed at a position where the back surface of the electric component mounted on the metal film of the dielectric substrate overlaps, or at a position where it contacts the edge of the electric component mounted on the metal film of the dielectric substrate. A microwave substrate having a patterned pattern formed thereon. 3. A frame is formed at a predetermined height around an upper surface of a dielectric substrate on which a metal film constituting the microwave substrate according to claim 1 is formed, and an inside and an outside of the frame are connected. A microwave package having a signal terminal formed thereon. 4. The microwave substrate according to claim 1, wherein a pattern exposing the dielectric substrate is formed at a plurality of positions.