JP2001185915A - Microstrip line structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microstrip line structure which can prevent a leakage of an unnecessary wave. SOLUTION: This structure is composed of a dielectric substrate 1, a ground conductor 2 formed on one surface of the dielectric substrate 1, a signal line 3 arranged on the other surface of the dielectric substrate 1, via-hole conductors 4 which are electrically connected to the ground conductor 2 and arranged in two arrays having an interval <=1/2 time as large as cutoff wavelength along the length of the signal line 3, a round part 5 which is electrically connected to the via-hole conductors 4, and a cover 6 which is electrically connected to the round part 5; and the cover 6 forms a space part 7 surrounding the signal line 3 and the space part 7 is electrically shielded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microstrip line structure for millimeter-wave and microwave transmission used in a vehicle-mounted radar or the like.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. H11-13609 discloses a prior art relating to a high-frequency transmission line structure for transmitting high-frequency signals such as millimeter waves and microwaves. This prior art will be described with reference to FIG. FIG. 5 is a schematic perspective view for explaining a microstrip line structure according to the related art.

[0005] As shown in FIG. 5, in the configuration of the prior art, a ground conductor 22 and an upper conductor 23 are formed on the upper and lower surfaces of a long dielectric substrate 21 having a thickness t. Two or more rows of via-hole conductors 24 are arranged on the dielectric substrate 21 so as to electrically connect the dielectric substrates 21 with a column interval of width a. The via-hole conductors 24, 24 form side walls of the dielectric waveguide, and are set so that leakage of electromagnetic waves does not occur. According to the configuration of the prior art, a waveguide region of t × a is formed, and this region A
A signal is transmitted in the longitudinal direction.

[0004]

As described above,
The conventional technology transmits and uses a high-frequency signal in the form of a dielectric waveguide, and has a different application from a microstrip line. In the case of the conventional technology, in order to connect to another line, an IC, or the like, The problem of requiring a converter arises.

[0005] It is an object of the present invention to solve the above-mentioned problems and to provide a microstrip line structure capable of shielding unnecessary waves propagating in a dielectric.

[0006]

In order to achieve the above-mentioned object, the present invention provides a dielectric substrate, a ground conductor formed on one surface of the dielectric substrate, and a dielectric substrate. A signal line disposed on the other surface, electrically connected to the ground conductor, and provided in the dielectric substrate at a pitch of 1/2 or less of a cutoff wavelength in a longitudinal direction of the signal line. Via-hole conductors arranged in rows, and a shield structure electrically connected to the via-hole conductor and forming a space surrounding the signal line and electrically shielding the space are provided. Microstrip line structure.

In order to achieve the above-mentioned object, a second aspect of the present invention provides a semiconductor device, comprising: a round portion in which the shield structure is electrically connected to the via-hole conductor; and a cover electrically connected to the round portion. The microstrip line structure according to claim 1, wherein the microstrip line structure is configured.

According to another aspect of the present invention, the shield structure is a side conductor electrically connected to the via-hole conductor, and an upper conductor electrically connected to the side conductor. 2. The microstrip line structure according to claim 1, wherein:

[0009]

An embodiment of the present invention will be described with reference to the drawings. INDUSTRIAL APPLICABILITY The present invention can be applied to a microstrip line structure or a coplanar line structure that can shield unnecessary waves propagating in a dielectric substrate. Description is omitted. FIG. 1 is a schematic perspective view for explaining a microstrip line structure according to the first embodiment of the present invention.

As shown in FIG. 1, a microstrip line structure according to a first embodiment of the present invention
And a ground conductor 2 formed on one surface of the dielectric substrate 1;
A signal line 3 disposed on the other surface of the dielectric substrate 1 and a pitch electrically connected to the ground conductor 2 and provided in the dielectric substrate 1 and having a pitch of 1/2 or less of a cutoff wavelength in the longitudinal direction of the signal line 3 The via-hole conductors 4 are arranged in two rows in the longitudinal direction at intervals. Since the via-hole conductors 4, 4 are arranged in the longitudinal direction of the signal line 3 at a pitch of 以下 or less of the cutoff wavelength in two rows in the longitudinal direction, unnecessary wave propagating in the dielectric substrate 1 is reduced. Propagation can be prevented. The via-hole conductor 4 can be formed by plating a through-hole, and various other configurations such as embedding of a conductive paste are possible.

A round portion 5 is provided at the upper end of the via-hole conductors 4 and 4 in the figure. A conductive adhesive or solder is applied to the surface of the round portion 5 as an adhesive layer according to the shape of the round portion 5.

A metal cover 6 or a cover 6 formed of a material such as a resin having a metal surface treated is disposed at an upper end of the round portion 5 in the drawing. As the metal material of the cover 6 or the surface treatment material of the cover 6, it is necessary to select a material having good adhesion to the material of the round portion 5 or the surface treatment material.

It is desirable to control the thickness of the adhesive layer of the round portion 5 so as to be greater than the control flatness of the surface of the dielectric substrate 1 and the surface of the cover 6 facing the round portion 5. When bonding the cover 6 to the round portion 5, the cover 6
Is preferably applied to the round portion 5 to secure adhesion.

Referring to FIG. 2, the microstrip line structure according to the first embodiment of the present invention will be further described. FIG. 2 is a sectional view for explaining the microstrip line structure according to the first embodiment of the present invention. As shown in FIG. 2, the cover 6 has convex surfaces 3 a, 3
b, and a lid-like configuration including a concave surface 3c that covers the signal line 3 at a predetermined interval. The two convex surfaces 3a, 3 of the cover 6
A space portion 7 is formed which is electrically shielded by the b, the concave surface 3c and the two rows of round portions 5. The space 7 prevents interference with the signal line. The space 7 is
By appropriately setting the height and width of the space, it is possible to prevent unnecessary waves such as reflected waves in the used frequency band from propagating in the waveguide mode.

In the microstrip line structure according to the first embodiment of the present invention described above, the cover 6
In cooperation with the round portion 5 electrically connected to the via-hole conductors 4, 4, a space 7 surrounding the signal line 3 is formed and a shield structure S for electrically shielding the space 7 is formed. I have.

The cover 6 is attached to the dielectric substrate 1 by:
The cover 6 and the dielectric substrate 1 are assembled on the basis of the positioning standard, fixed by screws or the like, and the whole is heated to a temperature higher than the melting temperature of the conductive adhesive or solder applied to the round portion 5, and the curing process Complete through such as. By attaching cover 6 to dielectric substrate 1, the inner surfaces of via hole conductor 4, round portion 5, and cover 6 are electrically shielded and made conductive.

According to the microstrip line structure according to the first embodiment of the present invention described above, it is possible to prevent unnecessary signal leakage and signal interference between circuits.

Further, according to the microstrip line structure according to the first embodiment of the present invention, the via-hole conductor 4
The ground conductor 2 and the cover 6 are not affected by dimensional accuracy such as the flatness of the dielectric substrate 1 and the round portion 5, and the conduction is reliably ensured. Since it has a simple configuration having a single-layer substrate and a cover as its basic configuration, cost can be reduced.

Further, according to the microstrip line structure according to the first embodiment of the present invention, it is possible to bond the dielectric substrates to each other, or to mount and cover the elements, and then attach the cover 6. Good assemblability. Various circuits can be combined. After all the dielectric substrates of the high-frequency circuit are integrated, it is also possible to mount necessary components and connect the circuits.

Next, a microstrip line structure according to a second embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 4 is a cross-sectional view illustrating a microstrip line structure according to a second embodiment of the present invention. The microstrip line structure according to the second embodiment of the present invention is shown in FIG.
2 is a modified example of the microstrip line structure according to the first embodiment described in 2 above, so different configurations will be described.
The same configuration is used.

As shown in FIG. 3, via-hole conductors 4,
4, side conductors 10 and 11 having an L-shaped cross section and fixed to side covers 8 and 9 are electrically connected to the upper end in the figure. An upper conductor 13 fixed to the flat cover 12 is disposed at the upper end of the side covers 8 and 9 and the side conductors 10 and 11 in the drawing, and the upper conductor 13 and the side conductors 10 and 11 are electrically connected. I have. The space 7 is formed by the upper conductor 13 and the side conductors 10 and 11.

In the microstrip line structure according to the second embodiment of the present invention described above, the side conductor 1
A shield structure S is formed by the upper conductor 13 electrically connected to the side conductors 10 and 11 and the upper conductor 13.
The shield structure S forms a space 7 surrounding the signal line 3 and electrically shields the space 7.

According to the microstrip line structure according to the second embodiment of the present invention described above, it is possible to prevent unnecessary signal leakage and signal interference between circuits.

The microstrip line structure according to the second embodiment of the present invention has a first layer mainly composed of the dielectric substrate 1, a second layer composed of the side covers 8, 9 and the side conductors 10, 11; Since the third layer composed of the cover 12 and the upper conductor 13 may be sequentially laminated and assembled, the production cost is low and the production time is short.

Next, a microstrip line structure according to a third embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 9 is a schematic perspective view for explaining a microstrip line structure according to a third embodiment of the present invention. The microstrip line structure according to the third embodiment of the present invention is a modification of the microstrip line structure according to the first embodiment described with reference to FIGS. Invite.

As shown in FIG. 4, in the microstrip line structure according to the third embodiment of the present invention, the end 1a is left as it is, and the signal line 3 is continuously connected from the end 1a.
, A long hole 14 is formed in the longitudinal direction. Slot 1
Reference numeral 4 is formed by a router (end mill), press working, or the like, and similarly to the microstrip line structure according to the first embodiment, various configurations such as formation by plating in through holes, embedding of a conductive paste, and curing are possible. .

In order to secure the electrical connection between the elongated hole 14 and the cover 6, an elongated round portion 15 is arranged at the upper end of the elongated hole 14 in the drawing. The long hole 14 and the cover 6 are
Through the same steps as in the round section 5 of the microstrip line structure according to the first embodiment, conduction is established through the step 5.

According to the microstrip line structure according to the third embodiment of the present invention described above, unnecessary signal leakage can be prevented and signal interference between circuits can be prevented.

Further, according to the microstrip line structure according to the third embodiment of the present invention, it is not necessary to machine a large number of via holes, and only a pair of elongated holes 14 are machined. Become. It is not necessary to manufacture a large number of round parts and attach them. It is only necessary to produce two long round parts 15 and attach them, so that it is possible to significantly reduce costs.

[0030]

According to the first aspect of the present invention, there is provided a dielectric substrate, a ground conductor formed on one surface of the dielectric substrate, a signal line disposed on the other surface of the dielectric substrate, and the ground conductor. Via-hole conductors provided in the dielectric substrate, the via-hole conductors being provided in the dielectric substrate and arranged in two rows at a pitch of 1/2 or less of a cutoff wavelength in a longitudinal direction of the signal line; The microstrip line structure is characterized by having a space electrically connected to a conductor and surrounding the signal line and having a shield structure for electrically shielding the space, so that unnecessary signal leakage occurs. And the signal interference between circuits can be prevented.

According to a second aspect of the present invention, the shield structure includes a round portion electrically connected to the via-hole conductor, and a cover electrically connected to the round portion. The microstrip line structure according to item 1 provides an excellent effect that unnecessary signal leakage can be prevented and signal interference between circuits can be prevented.

According to a third aspect of the present invention, the shield structure includes a side conductor electrically connected to the via-hole conductor;
2. The microstrip line structure according to claim 1, wherein the microstrip line structure is constituted by an upper conductor electrically connected to the side conductor, so that leakage of unnecessary signals can be prevented and signal interference between circuits can be prevented. This has an excellent effect that it can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view for explaining a microstrip line structure according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a microstrip line structure according to the first embodiment of the present invention.

FIG. 3 is a sectional view illustrating a microstrip line structure according to a second embodiment of the present invention.

FIG. 4 is a schematic perspective view for explaining a microstrip line structure according to a third embodiment of the present invention.

FIG. 5 is a schematic perspective view for explaining a microstrip line structure according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Dielectric board 1a ... End 2 ... Ground conductor 3 ... Signal line 3a ... Convex surface 3b ... Convex surface 3c ... Concave surface 4 ... Via-hole conductor 5 ... Round part 6 ... Cover 7 ... … Space 8… side cover 9… side cover 10… side conductor 11… side conductor 12… plane cover 13… upper conductor 14… long hole 15… long round part 21… dielectric Substrate 22: Ground conductor 23: Upper conductor 24: Via-hole conductor

Claims (3)

[Claims] 1. A dielectric substrate, a ground conductor formed on one surface of the dielectric substrate, a signal line disposed on the other surface of the dielectric substrate, and electrically connected to the ground conductor; Via-hole conductors provided in the dielectric substrate and arranged in two rows at a pitch of 1/2 or less of a cutoff wavelength in a longitudinal direction of the signal line, and electrically connected to the via-hole conductor. A microstrip line structure comprising a space surrounding the signal line and a shield structure for electrically shielding the space. 2. The micro-device according to claim 1, wherein the shield structure comprises a round portion electrically connected to the via-hole conductor, and a cover electrically connected to the round portion. Strip line structure. 3. The shield structure according to claim 1, wherein the shield structure includes a side conductor electrically connected to the via hole conductor, and an upper conductor electrically connected to the side conductor. Microstrip line structure.