JP2005142868A - Dielectric resonance antenna and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To fix a dielectric resonator onto a packaging board with sufficient strength, and to reduce height in a dielectric resonance antenna. <P>SOLUTION: The dielectric resonance antenna comprises the dielectric resonator 11; the packaging board 12, where the dielectric resonance resonator 11 is mounted onto a packaging surface; a feeder 12a that is extended to one portion of a packaging region in the dielectric resonator 11 for formation on the packaging surface, transmits a feeding signal to the dielectric resonator 11, and fixes the dielectric resonator 11 and the packaging board 12; a first earthed electrode 12b that is formed on the packaging surface including another one portion of the packaging region in the dielectric resonator 11 via the feeder 12a and a gap, and fixes the dielectric resonator 11 and the packaging board 12; and a second earthed electrode 12c that is formed on a surface opposite to the packaging surface of the packaging board 12, and is electrically connected to the first earthed electrode 12b via a through hole 13. The through hole 13 is formed at a region including the packaging region of the dielectric resonator 11. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a dielectric resonant antenna and a manufacturing method thereof.

  A dielectric resonance antenna (DRA-Dielectric Resonator Antenna) is used for a wireless LAN base station antenna and the like because it has less conductor loss than a microstrip antenna and can easily be widened and reduced in size.

  Such dielectric resonant antennas are described in, for example, Japanese Patent Application Laid-Open Nos. 2000-209019, 2000-209020, and 2001-298318.

Here, as described in these publications, the dielectric resonant antenna is composed of a dielectric resonator (dielectric) and a mounting substrate on which the dielectric resonator is mounted. The dielectric resonator includes probe pins, Power is supplied by a slot, a microstrip or the like.
JP 2000-209019 A JP 2000-209020 A JP 2001-298318 A

  In order for the dielectric resonant antenna to obtain the desired frequency characteristics, the dielectric resonator must be fixed at a predetermined position on the mounting substrate with sufficient strength.

  However, the technique described in the above-mentioned publication does not mention anything about fixing of the dielectric resonator.

  Accordingly, an object of the present invention is to provide a technique capable of fixing a dielectric at a predetermined position on a mounting substrate with sufficient strength in a dielectric resonant antenna.

  In order to solve the above problems, a dielectric resonant antenna according to the present invention includes a dielectric having a predetermined shape, a mounting substrate on which the dielectric is mounted on a mounting surface, and a tip at least a part of the mounting region of the dielectric. A power supply line formed of a conductive thin film extending to the mounting surface and transmitting a signal fed to the dielectric and fixing the dielectric and the mounting substrate; and via the power supply line and the gap A first ground electrode formed on the mounting surface including another part of the mounting region of the dielectric, and made of a conductive thin film that fixes the dielectric and the mounting substrate; and the mounting on the mounting substrate. And a second ground electrode formed on an opposite surface to the first ground electrode and electrically connected to the first ground electrode through a through hole.

  In a preferred aspect of the present invention, the through hole is formed in a region including a mounting region of the dielectric.

  In a further preferred aspect of the present invention, a resist layer is formed on an outer periphery of the dielectric mounting region and on the first ground electrode.

  In a further preferred aspect of the present invention, the dielectric has a height of 3.1 to 3.7 mm.

  In order to solve the above-described problem, a dielectric resonant antenna manufacturing method according to the present invention includes a feed line made of a conductive thin film and a first ground electrode made of a conductive thin film and formed through the gap with the feed line. A mounting substrate having a second ground electrode on the mounting surface and having a second ground electrode electrically connected to the first ground electrode through a through hole on the surface opposite to the mounting surface is prepared and bonded to the feeder line A dielectric having a resonator-side power supply line of the conductive thin film and a resonator-side ground electrode of the conductive thin film to be joined to the first ground electrode, and an outer periphery of the dielectric mounting region, A resist layer is formed on the first ground electrode, and at least one of the feed line in the resonator-side feed line and the dielectric mounting region, and in the resonator-side ground electrode and the dielectric mount region Said first contact A brazing member is applied to at least one of the electrodes, and the dielectric is placed on a mounting region of the mounting board so that the resonator-side power supply line is positioned on the power supply line, The member is melted and the dielectric is fixed to the mounting substrate.

  In a preferred aspect of the present invention, the through hole is formed in a region including a mounting region of the dielectric.

  In a further preferred aspect of the present invention, the resonator-side power supply line and the resonator-side ground electrode are formed by applying and baking a metal paste by screen printing.

  In a further preferred aspect of the present invention, the brazing member is a solder paste.

  According to the present invention, the following effects can be obtained.

  That is, since the dielectric and the mounting substrate are bonded and fixed by the first ground electrode in addition to the power supply line, the bonding strength is improved and the dielectric is fixed at a predetermined position on the mounting substrate with sufficient strength. It becomes possible to do.

  Also, even if the height of the dielectric is lowered, good resonance characteristics can be obtained, so that the height of the antenna can be reduced.

  Furthermore, since no gap is required on the outer periphery of the mounting area, the area occupied by the antenna can be reduced.

  Since the melted brazing member spreads only on the resonator-side power supply line, the power supply line, the resonator-side ground electrode, and the first ground electrode, the dielectric is accurately positioned on the mounting substrate. It is possible to fix it at an accurate position with sufficient strength.

  If a through hole is formed in the mounting region of the dielectric resonator, the brazing member goes from the through hole to the second ground electrode, so that the fixing strength of the dielectric resonator to the mounting substrate is greatly increased. Can do.

  Hereinafter, the best mode for carrying out the present invention will be described more specifically with reference to the drawings. Here, in the accompanying drawings, the same reference numerals are given to the same members, and duplicate descriptions are omitted. In addition, since description here is the best form by which this invention is implemented, this invention is not limited to the said form.

  1 is a perspective view showing a dielectric resonant antenna according to one embodiment of the present invention, FIG. 2 is an explanatory view showing a mounting surface of a mounting board in the dielectric resonant antenna of FIG. 1, and FIG. 3 is a dielectric resonant antenna of FIG. FIG. 4 is a graph showing the reflection characteristics of the dielectric resonator antenna of FIG. 1 in which the height of the dielectric resonator is 3.1 mm, and FIG. 5 is a diagram of the dielectric resonator. 1 is a graph showing the reflection characteristics of the dielectric resonant antenna of FIG. 1 with a height of 3.3 mm, and FIG. 6 shows the reflection characteristics of the dielectric resonant antenna of FIG. 1 with a height of the dielectric resonator of 3.5 mm. FIG. 7 is a graph showing the reflection characteristics of the dielectric resonant antenna of FIG. 1 in which the height of the dielectric resonator is 3.7 mm, and FIG. 8 shows the mounting surface of the mounting board in the dielectric resonant antenna as a comparative example. FIG. 9 is a cross-sectional view of the dielectric resonant antenna of FIG. Is a graph showing characteristics.

As shown in FIGS. 1 and 2, the dielectric resonant antenna 10 according to the present embodiment is a dielectric made of a dielectric material such as (Mg · Ca) TiO ₂ or Ba ₂ Ti ₉ O ₂₀ having a rectangular parallelepiped shape. It has a resonator (dielectric) 11 and a mounting substrate 12 on which the dielectric resonator 11 is mounted. In the present embodiment, the size of the dielectric resonator 11 is 10 mm long × 10 mm wide × 3.1 mm high. However, other sizes may be used.

  On the mounting surface of the mounting substrate 12, a power supply line 12 a made of a conductive thin film that transmits a signal fed to the dielectric resonator 11 and excites the signal extends to a part of the mounting region of the dielectric resonator 11. Is formed. A first ground electrode 12b made of a conductive thin film for fixing the dielectric resonator 11 and the mounting substrate 12 is supplied to the mounting surface including another part of the mounting region of the dielectric resonator 11. It is formed via the electric wire 12a and a gap. Further, a second ground electrode 12 c electrically connected to the first ground electrode 12 b through the through hole 13 is formed on the surface opposite to the mounting surface of the mounting substrate 12. A resist layer 14 is formed on the outer periphery of the mounting region of the dielectric resonator 11 and on the first ground electrode 12b.

  Here, the width of the power supply line 12a is 1.11 mm, the width of the resist layer 14 is 0.5 mm on the side where the power supply line 12a is exposed, and 1.5 mm in other locations. However, other dimensions may be used.

  In the present embodiment, the feed line 12a is formed over the entire length of one side in the mounting region of the dielectric resonator 11 having a rectangular shape, but it is sufficient that the tip thereof covers a part of the mounting region. . Furthermore, the tip may extend to the outside of the mounting area. That is, it is only necessary that the feed line 12 a has its tip extended to at least a part of the mounting region of the dielectric resonator 11.

  Further, in the illustrated case, the through hole 13 is formed in the mounting region of the dielectric resonator 11 and other regions. From the viewpoint of fixing strength of the dielectric resonator 11 to be described later, it is desirable that the through hole 13 is formed in the mounting region of the dielectric resonator 11 as described above. Good.

  On the bottom surface of the dielectric resonator 11, as shown in FIG. 3, the resonator-side power supply line 11a made of a conductive thin film corresponding to the shape of the power supply line 12a in the mounting region, and the first ground electrode in the mounting region are also provided. A resonator-side ground electrode 11b made of a conductive thin film corresponding to the shape of 12b is formed. In the present embodiment, the resonator-side power supply line 11a has a width of 1.11 mm, and the resonator-side ground electrode 11b has a width of 5 mm. However, other dimensions may be used.

  Then, as will be described later, the power supply line 12a and the resonator-side power supply line 11a are joined to each other via the solder, and the first ground electrode 12b and the resonator-side ground electrode 11b are joined to each other. And the mounting substrate 12 are fixed to each other. As described above, the dielectric resonator 11 and the mounting substrate 12 are joined by joining the first ground electrode 12b and the resonator-side ground electrode 11b in addition to joining the feeder line 12a and the resonator-side feeder line 11a. Since it is fixed, the joint strength between the two is improved. As a result, the dielectric resonator 11 can be fixed at a predetermined position on the mounting substrate 12 with sufficient strength.

  In addition, the dielectric material used for the dielectric resonator 11 can be applied other than those described above. Moreover, the shape of the dielectric resonator 11 is not limited to a rectangular parallelepiped, and can take various shapes such as a cylindrical shape, a wedge shape, and a spherical shape.

  Here, a manufacturing method of the dielectric resonant antenna having the above configuration will be described.

  First, the mounting substrate 12 and the dielectric resonator 11 described above are prepared. That is, the second ground electrode 12c that has the feeder 12a and the first ground electrode 12b on the mounting surface and is electrically connected to the first ground electrode 12b through the through hole 13 is opposite to the mounting surface. A dielectric resonator 11 having a mounting substrate 12, a resonator-side power supply line 11 a joined to the power supply line 12 a, and a resonator-side ground electrode 11 b joined to the first ground electrode 12 b is prepared. In the mounting substrate 12, a resist layer 14 is formed on the first ground electrode 12 b where the outer periphery of the mounting region of the dielectric resonator 11 is located.

  The resonator-side feed line 11a, the resonator-side ground electrode 11b, the feed line 12a, the first ground electrode 12b, and the second ground electrode 12c are formed by patterning a metal conductor layer such as copper or silver. . Specifically, for example, a metal paste such as silver can be formed by screen printing and baking, a method of forming a metal pattern layer by plating, a method of patterning a thin metal film by etching, or the like.

  Next, a brazing member such as a solder paste is applied to the power supply line 12a and the first ground electrode 12b in the mounting region of the dielectric resonator 11 by screen printing. It may be applied to the resonator-side power supply line 11a and the resonator-side ground electrode 11b, or may be applied to the resonator-side power supply line 11a, the power supply line 12a, the resonator-side ground electrode 11b, and the first ground electrode 12b. Also good. As the brazing member, other than the solder paste may be used as long as it is a conductor member that can be applied and can be reflowed.

  When the solder paste is applied, the dielectric resonator 11 is placed on the mounting region of the mounting board so that the resonator-side power supply line 11a is positioned on the power supply line 12a, and these are heated. Thereby, the solder paste is melted, the power supply line 12a and the resonator-side power supply line 11a are joined, and the first ground electrode 12b and the resonator-side ground electrode 11b are joined.

  At this time, the melted solder paste spreads to the resonator-side power supply line 11a, the power supply line 12a, the resonator-side ground electrode 11b, and the first ground electrode 12b with a small contact angle, but these conductive materials with a large contact angle. It does not spread in the region where the conductive thin film is not formed. Therefore, the dielectric resonator 11 is mounted on the mounting substrate 12 so that the power supply line 12a and the resonator-side power supply line 11a and the first ground electrode 12b and the resonator-side ground electrode 11b face each other accurately. Positioned.

  Finally, after being positioned in this way, the solder paste is hardened by leaving it at room temperature, and the dielectric resonator 11 is accurately positioned and fixed to the mounting substrate 12. This makes it possible to fix the dielectric resonator 11 to the mounting substrate 12 at a sufficient strength and at an accurate position. Therefore, it is possible to accurately lay out the feeding positions, and desired antenna characteristics can be stably obtained.

  Since the through hole 13 is formed in the mounting region of the dielectric resonator 11, when the dielectric resonator 11 is mounted on the mounting substrate 12 using a solder paste, the solder passes from the through hole 13 to the second ground electrode. Go around to 12c. Thereby, the fixing strength of the dielectric resonator 11 can be greatly increased.

  Here, the fixing strength is obtained by applying a load from the side of the dielectric resonator 11 and by the load when the dielectric resonator 11 is peeled off, that is, the maximum load. The mounting strength of the mounting board 12 having the through hole 13 in the mounting area was 887 (N), whereas the fixing strength of the mounting board having no through hole in the mounting area was 682 (N). That is, by forming the through hole 13 in the mounting region, the fixing strength increased 1.3 times. A precision universal testing machine AUTO GRAPH AG-I / R 50 kN manufactured by Shimadzu Corporation was used as an adhesion strength measuring device.

  The inventor has examined the relationship between the height of the dielectric resonator 11 and the reflection characteristics.

  That is, in addition to the reflection characteristics when the height of the dielectric resonator 11 is 3.1 mm as described above, when the height of the dielectric resonator 11 is 3.3 mm, and when it is 3.5 mm Data was obtained on the reflection characteristics when the thickness was 3.7 mm. FIG. 4, FIG. 5, FIG. 6 and FIG. 7 show the reflection characteristics when the dielectric resonator 11 is at the respective heights.

  As shown in the figure, good reflection characteristics can be obtained at any height, that is, the dielectric resonant antenna 10 using the dielectric resonator 11 having a height of 3.1 mm shown in FIG. It has been. It can be seen that the reflection characteristics can be adjusted by changing the height of the dielectric resonator 11.

  In addition, as a comparative example, a dielectric resonant antenna having a height of 3.7 mm for the dielectric resonator 11 was created, and data on its reflection characteristics was obtained. FIG. 8 shows a mounting surface of a mounting board of a dielectric resonant antenna as a comparative example, and FIG. 9 shows reflection characteristics of the dielectric resonant antenna.

  In FIG. 8, the mounting surface of the mounting substrate 12 in the dielectric resonant antenna as a comparative example is called a coplanar wave guide. In addition to the mounting region of the dielectric resonator 11, the feeder line 12 a and a gap therebetween are provided. Thus, a ground electrode 12d is formed. In the mounting area, a power supply line 12a extending from outside the mounting area, a power supply line 12a, and a ground electrode 12d and a land 12e are formed through a gap. Accordingly, the land 12e only serves to fix the dielectric resonator 11 to the mounting substrate 12, and its potential is indefinite.

  Then, the reflection characteristics (FIG. 9) of the dielectric resonator antenna shown in FIG. 8 in which the height of the dielectric resonator 11 is 3.7 mm and the present invention in which the height of the dielectric resonator 11 is 3.1 mm are shown. Comparing the reflection characteristics of the dielectric resonant antenna 10 (FIG. 4), the resonance frequencies are almost the same.

  Therefore, according to the dielectric resonant antenna 10 of the present embodiment having a structure in which the through hole 13 is provided in the mounting region of the dielectric resonator 11 on the mounting substrate 12 to have the ground potential, the antenna can be reduced in height. Is possible. In addition, since no gap is required on the outer periphery of the mounting area, the area occupied by the antenna can be reduced.

It is a perspective view which shows the dielectric resonance antenna which is one form of this invention. It is explanatory drawing which shows the mounting surface of the mounting board | substrate in the dielectric resonance antenna of FIG. It is explanatory drawing which shows the dielectric resonator in the dielectric resonance antenna of FIG. 1 from a bottom face. 2 is a graph showing reflection characteristics of the dielectric resonant antenna of FIG. 1 in which the height of the dielectric resonator is 3.1 mm. 2 is a graph showing reflection characteristics of the dielectric resonant antenna of FIG. 1 in which the height of the dielectric resonator is 3.3 mm. 2 is a graph showing the reflection characteristics of the dielectric resonant antenna of FIG. 1 in which the height of the dielectric resonator is 3.5 mm. 2 is a graph showing reflection characteristics of the dielectric resonant antenna of FIG. 1 in which the height of the dielectric resonator is 3.7 mm. It is explanatory drawing which shows the mounting surface of the mounting board | substrate in the dielectric resonance antenna which is a comparative example. It is a graph which shows the reflective characteristic of the dielectric material resonant antenna of FIG.

Explanation of symbols

10 Dielectric Resonant Antenna 11 Dielectric Resonator (Dielectric)
11a Resonator-side feed line 11b Resonator-side ground electrode 12 Mounting substrate 12a Feed line 12b First ground electrode 12c Second ground electrode 12d Ground electrode 12e Land 13 Through hole 14 Resist layer

Claims (8)

A dielectric with a predetermined shape;
A mounting board on which the dielectric is mounted on the mounting surface;
The front end is formed on the mounting surface extending to at least a part of the mounting region of the dielectric, and includes a conductive thin film that transmits a signal fed to the dielectric and fixes the dielectric and the mounting substrate. A feeder line;
A first ground electrode made of a conductive thin film formed on the mounting surface including another part of the dielectric mounting region via the power supply line and a gap and fixing the dielectric and the mounting substrate When,
A second ground electrode formed on a surface opposite to the mounting surface of the mounting substrate and electrically connected to the first ground electrode through a through hole;
A dielectric resonant antenna comprising: 2. The dielectric resonant antenna according to claim 1, wherein the through hole is formed in a region including a mounting region of the dielectric. 3. The dielectric resonant antenna according to claim 1, wherein a resist layer is formed on an outer periphery of the dielectric mounting region and on the first ground electrode. The dielectric resonant antenna according to any one of claims 1 to 3, wherein the height of the dielectric is 3.1 to 3.7 mm. A power supply line made of a conductive thin film and a first ground electrode made of a conductive thin film and formed through a gap with the power supply line are provided on the mounting surface and electrically connected to the first ground electrode through a through hole. A mounting board having a second ground electrode connected to the mounting surface on the opposite side of the mounting surface;
Preparing a dielectric having a resonator-side power supply line of a conductive thin film bonded to the power supply line and a resonator-side ground electrode of a conductive thin film bonded to the first ground electrode;
Forming a resist layer on the outer periphery of the dielectric mounting region on the first ground electrode;
At least one of the power supply line in the resonator-side power supply line and the dielectric mounting region and at least one of the first ground electrode in the resonator-side ground electrode and the dielectric mounting region Apply the attachment material,
The dielectric is placed in a mounting region of the mounting substrate so that the resonator-side power supply line is positioned on the power supply line,
Melting the brazing member and fixing the dielectric to the mounting substrate;
A method for manufacturing a dielectric resonant antenna. 6. The method for manufacturing a dielectric resonant antenna according to claim 5, wherein the through hole is formed in a region including a mounting region of the dielectric. 7. The method for manufacturing a dielectric resonant antenna according to claim 5, wherein the resonator-side feed line and the resonator-side ground electrode are formed by applying a metal paste by screen printing and baking. The method for manufacturing a dielectric resonant antenna according to claim 5, wherein the brazing member is a solder paste.

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