JP2002050904A - Dielectric multilayer device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce loss as device characteristics, which is generated inside a dielectric multilayer device by electric field concentration at the edge of a stripline conductor formed by usual screen printing, where the loss for a prior art is great. SOLUTION: The thickness of a side portion 1103 of the stripline conductor inside a dielectric multilayer device is increased to a larger value than a center portion 1104 of the strip line conductor. The inside of the side portion 1103 is formed by using a material different from that of the surface of it. The increasing thickness of the side portion 1103 of the strip line conductor allows the edge angle of the side portion 1103 to become larger, and the conductor loss due to electric field concentration on the side portion 1103 is decreased to improve the loss of the device characteristics. Since the thickness of the stripline is large only at the side portion 1103, occurrence of a crack is suppressed, and degradation in electric characteristics and mechanical strength is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric laminated device mainly used for high-frequency radio equipment such as a portable telephone.

[0002]

2. Description of the Related Art In recent years, with the miniaturization of communication equipment, dielectric laminate devices that are advantageous for miniaturization of high-frequency devices are often used. Hereinafter, an example of the above-described conventional dielectric laminated device will be described with reference to the drawings.

FIG. 4 is an exploded perspective view of a strip line conductor formed by ordinary screen printing of a conventional dielectric laminated device. In FIG.
a, 101b, 101c, 101d, and 101e are dielectric layers; 102a and 102b are shield conductors;
03b, 104a, 104b, 104c are stripline conductors, 105a, 105b, 106a, 106b, 1
06c, 106d, 106e, and 106f indicate outer conductors.

[0004] In a laminate composed of dielectric layers 101a to 101e, a shield conductor 102a, stripline conductors 403a and 403b, and a stripline conductor 104 are provided.
a, 104b, 104c, and a shield conductor 102b are sequentially arranged between the dielectric layers, and further, outer conductors 106a, 106b, 106c, 106e on the front and left and right side surfaces of the laminate.
And 106f connect the shield conductors 102a and 102b to form a ground terminal, and the external conductor 106d
Are connected to the common short-circuited ends of the shield conductors 102a and 102b and the strip line conductors 403a and 403b to serve as ground terminals, and the outer conductors 105a and 1
05b is connected to the stripline conductors 104a and 104b, respectively, to form input / output terminals.

The function of the thus-configured dielectric laminated device will be described below.

The strip line conductors 403a and 403b constitute a 1/4 wavelength short-circuit type resonator, and the strip line conductor 104c is the strip line conductors 403a and 403b.
And a quarter-wavelength short-circuited resonator is coupled by forming a capacitor capacitance by opposing a part of the strip line conductors 403a and 403b, respectively. To form a capacitor capacitance by placing
By connecting one of the stripline conductors 104a, 104b to the external conductors 105a, 105b, they function as input / output terminals. Therefore, the dielectric laminate device of FIG. 4 functions as a bandpass filter having the external conductors 105a and 105b as input / output terminals.

[0007]

However, in the above configuration, the edge angle of the side portion of the strip line conductor is reduced, and the conductor loss due to the electric field concentration on the sharp portion of the side line is increased. Loss also increases. Regarding the above-mentioned “edge angle becomes smaller” in FIG.
This will be described with reference to FIG.

FIG. 5 is an end view of the conventional dielectric laminated device shown in FIG. 4 cut along a plane substantially orthogonal to the strip line conductors 403a and 403b having a substantially parallel relationship. is there. As shown in FIG. 5, edge portions 1403 of stripline conductors 403a and 403b
Is smaller, the edge 1403
Electric field concentration occurs.

When the strip line conductors 403a and 403b are uniformly thickened to increase the angle of the edge portion in order to solve this problem, the difference in the coefficient of thermal expansion between the metal serving as the conductor and the dielectric layer causes the firing process. The stress applied to the inside of the multilayer device at the time of temperature drop or solder reflow increases. Due to the increased stress, cracks are generated in the laminated device, and as a result, there is a problem that electrical characteristics are degraded and mechanical strength is reduced.

[0010] The distribution of the current flowing through the stripline conductor 403 has a bias. The bias of the current distribution will be described with reference to FIG. FIG. 10 is a diagram showing a distribution of a current flowing through the strip line conductor 403a of FIG. 4 which constitutes a quarter wavelength resonator. As shown in FIG.
It can be seen that the current distribution is larger on the short end side and smaller on the open end side. By the way, since the thickness of the conventional stripline conductor 403a is substantially uniform, in the stripline conductor 403a, the conductor loss at the short-circuited end where the current is concentrated is larger than the conductor loss at the open end. This is equivalent to the fact that the resistance on the short-circuit end side is larger than the resistance on the open end side. Therefore, there is a problem that a loss as a filter characteristic is large. This problem,
The same occurred in the stripline conductor 403b.

[0011] A similar problem also occurs in a stripline conductor constituting a half-wavelength resonator. Figure 1
FIG. 1 shows a distribution of a current flowing through a stripline conductor forming a half-wavelength resonator. As shown in FIG.
In the case of the stripline conductor constituting the two-wavelength resonator, it can be seen that there is a portion where a large amount of current flows in the center. Since the thickness of the conventional stripline conductor is substantially uniform, even in the stripline conductor forming the half-wavelength resonator, the resistance value at the short-circuit end side at the center is larger than the resistance value at the open end side. Therefore, there is a problem that a loss as a filter characteristic is large.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a dielectric laminated device that does not easily cause electric field concentration which causes an increase in conductor loss.

Another object of the present invention is to provide a dielectric laminated device in which the resistance of the stripline conductor is averaged as compared with the prior art.

[0014]

In order to solve the above-mentioned problems, a first aspect of the present invention (corresponding to claim 1) is to provide a laminated body including a plurality of dielectric layers and a laminate inside the laminated body. A plurality of stripline conductors arranged, wherein at least a portion of at least one of the plurality of stripline conductors has a thicker side portion than a central portion. It is a laminated device.

According to a second aspect of the present invention (corresponding to claim 2), the at least one strip line conductor has a length of 1/4.
The dielectric laminated device according to the first aspect of the present invention, wherein a short-wavelength-type short-circuited resonator is formed, and the thickness of a side portion on the short-circuit end side of the resonator is thicker than that of a central portion.

According to a third aspect of the present invention (corresponding to claim 3), the at least one stripline conductor is preferably a half of the stripline conductor.
An open-wavelength type resonator is formed, and the first book having a thicker side portion than the central portion in a portion of the resonator substantially １ ／ wavelength away from the open end in the wavelength direction. It is a dielectric laminated device according to the invention.

A fourth aspect of the present invention (corresponding to claim 4) is a dielectric comprising a laminated body composed of a plurality of dielectric layers and a plurality of strip line conductors disposed inside the laminated body. A method of manufacturing a laminated device, comprising: forming a stripline conductor having a thickness of at least one side portion thicker than a center portion on a predetermined dielectric layer material, and further forming another strip material on the stripline conductor. This is a method for manufacturing a dielectric laminated device in which a laminate is press-bonded.

A fifth aspect of the present invention (corresponding to claim 5) provides a laminate comprising a plurality of dielectric layers, and a plurality of stripline conductors disposed inside the laminate. Among the stripline conductors, at least one of the stripline conductors is a dielectric laminate device in which the thickness of a portion where current is more concentrated is thicker than that of a portion where current is less concentrated.

According to a sixth aspect of the present invention (corresponding to claim 6), the at least one strip line conductor forms a 1/4 wavelength tip short-circuit type resonator, and the thickness of the resonator on the short-circuit end side. Is the dielectric laminated device according to the fifth aspect of the present invention, which is thicker than the open end side.

According to a seventh aspect of the present invention (corresponding to claim 7), the at least one stripline conductor forms a half-wavelength open-ended resonator and is substantially larger than the open end of the resonator. The dielectric laminated device according to the fifth aspect of the present invention, wherein the thickness of the portion separated by １ ／ wavelength is thicker than the open end portion.

An eighth aspect of the present invention (corresponding to claim 8) is a dielectric comprising a laminated body composed of a plurality of dielectric layers and a plurality of strip line conductors disposed inside the laminated body. A method for manufacturing a laminated device, comprising: forming a stripline conductor on a predetermined dielectric layer material in which the thickness of a portion where more current is concentrated is thicker than that of a portion where current is less concentrated, and another stripline conductor is formed thereon. This is a method for manufacturing a dielectric laminated device in which a dielectric layer material is pressure-bonded and laminated.

According to a ninth aspect of the present invention (corresponding to claim 9), in a portion where the thickness of the strip line conductor is relatively thick, an inner material and an outer material are different from each other. A fifth, sixth, or seventh dielectric stacked device according to the present invention.

According to a tenth aspect of the present invention (corresponding to claim 10),
A plurality of shield conductors are arranged inside the laminate, and at least two 1-conductors are provided between the plurality of shield conductors.
A 波長 wavelength short-circuited resonator and a strip line conductor facing a part of the 波長 wavelength short-circuited resonator are arranged, and the strip line conductor includes two 個 wavelength strip resonators.
According to the first aspect of the present invention, a short-wavelength-tip short-circuited resonator is coupled to each other to form a multi-stage filter, and a part of the quarter-wavelength short-circuited-type resonator is thicker than other parts. It is a dielectric laminated device of the description.

According to an eleventh aspect of the present invention (corresponding to claim 11),
In a communication device including a transmitter and a receiver, first,
A communication apparatus including any one of the second, third, fifth, sixth, seventh, and tenth dielectric laminate devices according to the present invention as an element.

[0025]

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

(First Embodiment) A dielectric laminated device according to a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of a dielectric laminated device according to a first embodiment of the present invention. In FIG. 1, 101 is a dielectric layer, 102 is a shield conductor, 103 and 104 are stripline conductors, 105 and 1
06 indicates an outer conductor.

Here, a laminated structure of the dielectric laminated device of the first embodiment will be described. A first shield conductor 102a is disposed on the upper surface of the first dielectric layer 101a, and the second dielectric layer 101 is disposed above the conductor 102a.
b, and two strip line conductors 103a and 103b are arranged on the upper surface of the dielectric layer 101b.

Further, a third dielectric layer 101c is laminated on the conductor 103, and three strip line conductors 104a, 104b, 104 are formed on the upper surface of the dielectric layer 101c.
c is arranged. In addition, a fourth
, A second shield conductor 102b is disposed on the upper surface of the dielectric layer 101d, and a fifth dielectric layer 101e is laminated above the conductor 102b. Thus, a laminated structure of the dielectric laminated device is formed.

Further, external conductors 106a are provided on the front surface of the laminated body composed of the dielectric layers 101a to 101e, and external conductors 105a, 105b, 106b, 106 are provided on the side surfaces of the laminated dielectric.
c, 106d, and 106e, and an external conductor 106d on the back surface of the laminate. The connection relationship between these external conductors and the electrodes formed on each dielectric layer will be described below.

The first shield conductor 102a, the short-circuited end on the back side of the laminate where the stripline conductors 103a and 103b are connected together, and the second shield conductor 102b are connected to the external conductor 106d and grounded. . Also, the stripline conductor 104a and the external conductor 105a are connected, and the stripline conductor 104b and the external conductor 105b are connected. Further, the first shield conductor 102a and the second shield conductor 102b are connected to the outer conductors 106a, 106b,
106c, 106e, and 106f are connected to ground, and outer conductors 106b, 106f are connected to 106a
And 106c and 106e are connected to 106d, respectively.

Incidentally, the strip line conductor 103
1a and 103b, as shown in FIGS. 1 and 2 (a), the side portion 1103 has a thickness several tens times the skin depth in the microwave region. For example, the stripline conductor 10
If 3a and 103b are made of silver, the skin depth in the 2 GHz band is about 1.5 μm, and the side portion 1
The thickness of 103 is formed to be 30 μm or more. FIG. 2A shows the dielectric laminate device of the first embodiment shown in FIG.
It is an end view when it cuts in the plane substantially orthogonal to 03a, 103b.

The function of the dielectric laminated device of the first embodiment configured as described above will be described below with reference to FIGS.

The stripline conductors 103a and 103b are grounded via an external conductor 106d to form a quarter-wavelength short-circuited resonator, and the stripline conductor 104c faces a part of the stripline conductors 103a and 103b, respectively. By arranging them, the capacitor capacity is formed and acts as an inter-stage coupling capacity.

The strip line conductor 104a is disposed so as to face a part of the strip line conductor 103a, and the strip line conductor 104b is
b are respectively opposed to a part of the external conductor 10a to form a capacitor capacitance.
5a, the stripline conductor 104b is connected to the outer conductor 105.
b to form input / output terminals. Therefore,
The dielectric laminated device of FIG.
It functions as a band pass filter having 5b as an input / output terminal.

FIG. 2 (a) shows the state of FIG.
FIG. 3 is an end view of an electrode of the dielectric laminated device shown in FIG.
Side part 1 having an edge angle larger than (see FIG. 5)
103, and the side portion 1 of the stripline conductor.
The conductor loss due to the electric field concentration on 103 is suppressed.

The stripline conductors 103a and 103a
In order to make the thickness of the side portion 1103 of FIG. 03b thicker than that of the central portion 1104, as shown in FIG.
Before laminating to 101e, on the dielectric layer 101b,
Stripline conductors 103a and 103b whose side portions are thicker than the central portion are formed.

In this manner, the strip line conductor 1
Since the thicknesses of the layers 03a and 103b are not uniform, the laminate 10 having the dielectric layers 101a to 101e
When baking 0, the stress due to the difference in heat shrinkage can be minimized, and the occurrence of cracks can be suppressed. Stripline conductor 1 of laminated body 100 after firing
One end surfaces of the reference numerals 03a and 103b are shown as in FIG.

Next, a method for manufacturing the dielectric laminated device of the present invention will be described. As a method of forming each conductor, a normal screen printing method is used, in which a dielectric green sheet is laminated and a conductor pattern is printed in order, integrated by press bonding and fired, and then the external conductor is printed and baked. As for the strip line conductor 103, after a strip line conductor pattern is printed on the upper surface of the dielectric green sheet 101b and dried, a pattern of only the side portion of the strip line conductor is printed on the strip line conductor pattern. It forms by doing. By the above method, a strip line conductor having a cross-sectional shape as shown in FIG. 2 is obtained.

Further, even when each conductor pattern is formed by printing on a dielectric green sheet, and then laminated and press-bonded in order, a strip line conductor having a similar cross-sectional shape can be obtained.

As described above, according to the present embodiment, by increasing the edge angle of the side portion 1103 of the strip line conductor, the conductor loss of the strip line conductor can be reduced. When used as a resonator, loss as a filter characteristic can be improved. Furthermore, since only the side portion 1103 is thick, it is possible to suppress the occurrence of cracks due to the difference in the coefficient of thermal expansion between the dielectric and the conductor.

The side portion 1103 shown in FIG.
2B, the same effect can be obtained even if the inside 1106 of the stripline conductor 103 is made of a material different from that of the conductor 1105 on the surface as shown in FIG. 2B. The material of the inside of the stripline conductor 1106 is not particularly limited as long as it is different from the conductor 1105 on the surface. A material having a coefficient of thermal expansion intermediate between the coefficient of thermal expansion of the dielectric and the coefficient of thermal expansion of the conductor is preferable.

According to this, the stress due to the difference in thermal shrinkage in the thickened portion of the strip line conductor can be further reduced, and a decrease in mechanical strength and a deterioration in electrical characteristics due to internal cracks can be suppressed.

Further, the 1/4 wavelength tip short-circuit type resonator 1
03 is a half of the strip line conductor 703 in FIG.
A similar effect can be obtained even with an open-ended wavelength resonator.

(Second Embodiment) Hereinafter, a dielectric laminated device according to a second embodiment of the present invention will be described with reference to the drawings.

FIGS. 3 and 6 are exploded perspective views of a dielectric laminated device according to a second embodiment of the present invention. The laminated structure and functions are the same as those in the first embodiment, and corresponding elements are denoted by the same reference numerals. The difference from the first embodiment is that the strip line conductor 303 has a thicker portion near the connection portion with the external conductor than other portions.

As described above, according to the present embodiment, 1 /
In the four-wavelength short-circuited resonator, the current concentrates near the short-circuit end, particularly at the side portion thereof. Therefore, the entire structure is not made thick. Can be made smaller than before. In other words, even in a quarter-wavelength open-ended resonator, the resistance value can be averaged, whereby the conductor loss can be suppressed.

Further, by increasing the thickness of the short-circuited end of the strip line conductor, the contact resistance with the external conductor can be reduced. If the strip line conductor is used as a resonator, the loss as a filter characteristic is also improved. can do.

Further, since the strip line conductor near the open end is thin, if the strip line conductor 104 is arranged so as to oppose this portion, the undulation of the strip line conductor is small, and the interstage coupling capacitance and the input / output capacitance are stabilized. It is possible to form the semiconductor device by forming the structure, which is effective in improving the yield.

The present invention is not limited to the design of the interstage coupling capacitance and the input / output capacitance, but also includes all the components that form the capacitor capacitance by arranging a part of the resonator and a part of the strip line conductor to face each other, such as a loading capacitance. In the case of (1), a similar effect can be obtained.

Also, in the half-wavelength open-ended resonator, the vicinity of a portion separated by a quarter wavelength from the open end where current is concentrated (703 in FIG. 8) or a side portion thereof (7 in FIG. 9).
By making the layer 03) thicker, the resistance at the portion where the current is concentrated can be made smaller than before. That is, 1/2
The resistance value can be averaged also in the open-wavelength resonator.

In each of the above embodiments, a two-stage band-pass filter has been described. However, the same applies to various filters such as a low-pass filter, a high-pass filter, and a band elimination filter, or a multi-stage filter having three or more stages. The effect is obtained. Further, in each of the above-described embodiments, the edge angle of the resonator is increased. However, the same effect can be obtained by using this structure for a main line such as an inductor constituting the various filters.

Further, in a communication device provided with a transmitter and a receiver, the communication device including the dielectric laminate device in the above-described embodiment as an element also belongs to the present invention. The dielectric laminate device may be provided inside the transmitter or the receiver, or may be provided separately from the transmitter or the receiver.

[0054]

As described above, according to the present invention, by increasing the thickness of the side portion of the strip line conductor, a large edge angle is provided, and conductor loss due to electric field concentration at the sharp portions at both ends can be improved. Further, since only the sharp portion is thick, it is possible to suppress the occurrence of cracks due to the difference in the coefficient of thermal expansion between the dielectric and the conductor, thereby preventing the deterioration of the electrical characteristics and the decrease in the mechanical strength. Further, by increasing the thickness of the short-circuited end of the strip line conductor, the contact resistance with the external conductor can be reduced, and if the strip line conductor is used as a resonator, the loss as a filter characteristic can be improved. it can. Furthermore, if only the vicinity of the short-circuit end of the strip line conductor is made thicker than other portions, when forming the capacitor capacitance near the open end, the undulation of the opposed strip line conductor is small, and the capacitance can be easily designed. Can be.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a dielectric laminated device according to a first embodiment of the present invention.

FIG. 2 is a sectional view of an electrode of the dielectric laminate device according to the first embodiment of the present invention.

FIG. 3 is an exploded perspective view of a dielectric laminated device according to a second embodiment of the present invention.

FIG. 4 is an exploded perspective view of a conventional dielectric laminated device.

FIG. 5 is a sectional view of an electrode of a conventional dielectric laminated device.

FIG. 6 is an exploded perspective view of a dielectric laminated device according to a second embodiment of the present invention.

FIG. 7 is an exploded perspective view of the dielectric laminated device according to the first embodiment of the present invention.

FIG. 8 is an exploded perspective view of a dielectric laminated device according to a second embodiment of the present invention.

FIG. 9 is an exploded perspective view of a dielectric laminate device according to a second embodiment of the present invention.

FIG. 10 is a diagram showing a distribution of a current flowing through a stripline conductor forming a quarter-wavelength resonator.

FIG. 11 is a diagram showing a distribution of a current flowing through a stripline conductor forming a half-wavelength resonator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 100 Laminated body 101 Dielectric layer 102 Shield conductor 103,104,303,403,703 Stripline conductor 105,106 Outer conductor 1103 Side 1104 Central part 1105 Conductor on the surface of stripline conductor 103 1106 Inside of stripline conductor 103

Continued on the front page (72) Inventor Hiroshi Kagata 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. F term (reference) 5J006 HB04 HB05 HB21 JA01 LA02 LA16 NA04 NB07 NC03 5J014 CA02 CA43 CA57

Claims (11)

[Claims] 1. A laminate comprising a plurality of dielectric layers,
A plurality of strip line conductors disposed inside the laminate, wherein a thickness of at least a part of a side portion of at least one of the strip line conductors in the plurality of strip line conductors is a central portion. Thicker dielectric stacked devices. 2. The at least one stripline conductor forms the quarter-wavelength short-circuited resonator, and the side of the short-circuited end of the resonator has a thickness greater than that of the central portion. The dielectric laminate device according to claim 1, wherein the thickness is also large. 3. The at least one stripline conductor forms the half-wavelength open-ended resonator, and the resonator is substantially 波長 wavelength apart from the open end in the wavelength direction. 2. The dielectric laminate device according to claim 1, wherein the thickness of the side portion in the bent portion is larger than that of the central portion. 4. A laminate comprising a plurality of dielectric layers,
A method of manufacturing a dielectric laminate device comprising a plurality of stripline conductors disposed inside the laminate, wherein a thickness of at least one side portion is centered on a predetermined dielectric layer material. A method of manufacturing a dielectric laminated device in which a stripline conductor thicker than a portion is formed, and another dielectric layer material is compression-laminated thereon. 5. A laminate comprising a plurality of dielectric layers,
A plurality of stripline conductors disposed inside the laminate, wherein at least one of the plurality of stripline conductors has a thickness at a portion where a current is more concentrated, and Dielectric laminate device that is thicker than the area where no concentration occurs. 6. The device according to claim 5, wherein the at least one stripline conductor forms a quarter-wavelength short-circuited resonator, and the short-circuited end of the resonator is thicker than the open-ended side. Dielectric laminated device. 7. The at least one strip line conductor forms a half-wavelength open-ended resonator, and the thickness of a portion substantially １ ／ wavelength away from the open end of the resonator is an open-ended resonator. The dielectric laminate device according to claim 5, which is thicker than the portion. Dielectric laminate device. 8. A laminate comprising a plurality of dielectric layers,
A method of manufacturing a dielectric laminated device comprising a plurality of stripline conductors disposed inside the laminated body, wherein a thickness of a portion where current is more concentrated on a predetermined dielectric layer material is increased. A method of manufacturing a dielectric laminated device in which a thicker stripline conductor is formed than a portion where current does not concentrate, and another dielectric layer material is compression-laminated thereon. 9. The dielectric according to claim 1, wherein an inner material and an outer material of a portion where the thickness of the stripline conductor is relatively large are different from each other. Stacked device. 10. A plurality of shield conductors are arranged inside the laminate, and at least two 1/4 wavelength tip short-circuiting type resonators are provided between the plurality of shield conductors. A stripline conductor facing a part of the short-circuited resonator is disposed, and the stripline conductor couples the two quarter-wavelength short-circuited resonators to form a multi-stage filter. And said 1 /
2. The dielectric laminated device according to claim 1, wherein a part of the four-wavelength tip short-circuit type resonator is thicker than other parts. 11. A communication device provided with a transmitter and a receiver, wherein the dielectric laminated device according to any one of claims 1, 2, 3, 5, 6, 7, and 10 is included as an element. Communication equipment.