JP2004152836A - Multilayer circuit board for high frequency wave - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multilayer circuit board for a high frequency wave which has a small size and in which a production cost is suppressed. <P>SOLUTION: A cutout section 2 is formed from the upper surface of a rectangular laminate 1 made by laminating a plurality of dielectric layers 1a-1f to one side face. An electronic element 6 is placed on the surface of the dielectric layer exposed to the forming region of the cutout section 2. Strip lines 5 electrically connected to the element 6 between the dielectric layers disposed on the non-forming region of the cutout section 2 are provided on the upper and lower surfaces of the laminate 1. A ground electrode 3 is provided on the other side face disposed on the non-forming region of the cutout section, and electrically connected to the one end side of the line 5 on the other side face. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a high-frequency multilayer circuit board used for a semiconductor device and a composite electronic component.
[0002]
[Prior art]
High frequency multilayer circuit boards are widely used in semiconductor devices and composite electronic components.
As such a conventional high-frequency multilayer circuit board, for example, as shown in FIG. 4, a strip line (not shown) is formed inside a rectangular laminate formed by laminating a plurality of dielectric layers, and the rectangular There is known a structure in which a concave portion 52 is formed at the center of the upper surface of the shape laminate, and an electronic component element 53 electrically connected to the strip line is mounted on the surface of the dielectric layer exposed at the bottom of the concave portion. (For example, see Patent Document 1).
[0003]
As the electronic component element 53, for example, a chip-type electronic component such as a capacitor or a SAW element is used. In this case, the electronic component element 53 and the strip line constitute a filter circuit or the like. In addition, a semiconductor element may be used as the electronic component element 53. In this case, an oscillation circuit is configured by the electronic component element 53 and the strip line.
[0004]
When a SAW element or a semiconductor element is used as the electronic component element 53, it is general that the electronic component element 53 is hermetically sealed by closing the opening of the concave portion 52 with a resin material or a metal lid. is there.
[0005]
The above-described conventional high-frequency multilayer circuit board is manufactured by the following manufacturing method.
That is, first, a large-scale laminate having a plurality of substrate regions corresponding to the rectangular laminate 51 is formed by a conventionally well-known ceramic green sheet laminating method, and each substrate region is formed in each substrate region of the large-scale laminate. A predetermined concave portion 52 is formed at the center of the rectangular laminate, and then the large laminate is integrally fired, and then the large laminate is cut along the boundary between adjacent substrate regions to thereby form a plurality of rectangular laminates. A multilayer circuit board as a product is completed by mounting the electronic component element 53 in the region where the concave portion 52 of the obtained rectangular laminated body 51 is formed (see, for example, Patent Document 2).
[0006]
[Patent Document 1]
JP 2001-102807 A (FIG. 3)
[Patent Document 2]
JP 2001-217334 A (FIGS. 2 to 5)
[0007]
[Problems to be solved by the invention]
However, according to the above-described conventional high-frequency multilayer circuit board, the concave portion 52 for accommodating the electronic component element 53 is located at the center of the upper surface of the rectangular laminated body 51. Usually, it is arranged in the peripheral area of the rectangular laminate 51 located outside the recess 52. For this reason, it is necessary to secure a certain large area in the peripheral area of the rectangular laminated body 51, and it is difficult to reduce the size of the entire structure. In addition, the strip line and the strip line are electrically connected to the electronic component element 53. There is also a great restriction on the layout of the internal wirings to be connected to each other, which has a drawback that the degree of freedom in design is low.
[0008]
Therefore, in order to reduce the overall structure of the high-frequency multilayer circuit board, it is conceivable to dispose a part of the strip line immediately below the recess. In this case, however, the strip line and the strip line are disposed immediately below the recess. Since the distance between the strip line and the ground electrode becomes short, the Q value of the strip line decreases accordingly, and it has a disadvantage that it is difficult to obtain desired characteristics.
[0009]
On the other hand, in order to reduce the area of each substrate region provided in the large-sized laminate in order to make the above-described conventional high-frequency multilayer circuit substrate small, a large number of concave portions corresponding to each substrate region in a one-to-one correspondence are required. It must be formed at high density. In this case, punch dies for forming individual recesses in the ceramic green sheet must be finely formed, and these punch dies must be arranged at a high density in accordance with the arrangement pitch of the substrate region. In addition, a complicated manufacturing facility for forming the concave portion causes a disadvantage that the production cost is increased.
[0010]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-described drawbacks, and has as its object to provide a high-frequency multilayer circuit board that is small in size and can keep production costs low.
[0011]
[Means for Solving the Problems]
The high-frequency multilayer circuit board according to the present invention is configured such that a notch is formed from the upper surface to at least one side surface of a rectangular laminate formed by stacking a plurality of dielectric layers, and a dielectric exposed in a region where the notch is formed. An electronic component element is mounted on the surface of the body layer, and a strip line electrically connected to the electronic component element between dielectric layers located in the not-formed area of the cutout portion, the upper surface of the rectangular laminate, A ground electrode is provided on the lower surface and the other side surface located in a region where the notch is not formed, and the ground electrode is electrically connected to one end side of the strip line on the other side surface.
[0012]
Further, the high frequency multilayer circuit board according to the present invention is characterized in that the notch is provided at a corner of the upper surface of the rectangular laminate.
[0013]
Further, the electronic component element is covered with a shield case, and a height position of the upper surface of the shield case is set to be equal to or lower than the upper surface of the rectangular laminate. It is assumed that.
[0014]
According to the high-frequency multilayer circuit board of the present invention, a notch is formed from the upper surface to one side surface of the rectangular laminate, and the electronic component element is mounted on the surface of the dielectric layer exposed in a region where the notch is formed. Therefore, the strip line and the internal wiring for electrically connecting the strip line to the electronic component element can be arranged under relatively few restrictions, without lowering the Q value of the strip line. The degree of freedom in design can be increased, and the overall structure can be reduced in size.
[0015]
Further, according to the high frequency multilayer circuit board of the present invention, the notch is provided at the upper corner of the rectangular laminated body, so that the high frequency multilayer circuit board is manufactured by "multi-piece" from the large laminated body. In this case, it is only necessary to form one concave portion for at least two substrate regions in the large-sized laminate, so that the manufacturing equipment for forming the concave portion can be simply maintained. This makes it possible to reduce the production cost of the high-frequency multilayer circuit board.
[0016]
Further, according to the multilayer circuit board for high frequency of the present invention, the height position of the upper surface of the shield case is set to be equal to or lower than the upper surface of the rectangular laminate, and thereby, It is also possible to reduce the height of the circuit board.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is an external perspective view of a high-frequency multilayer circuit board according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the high-frequency multilayer circuit board shown in FIG. 1. The high-frequency multilayer circuit board shown in FIG. A strip line 5 is provided inside the laminate 1, a notch 2 is formed on the upper surface of the rectangular laminate 1, and the strip line 5 is formed on the surface of the rectangular laminate 1 facing the notch 2. It has a structure in which electronic component elements 6 to be electrically connected are mounted.
[0018]
The rectangular laminate 1 is formed by laminating a plurality of dielectric layers made of a glass-ceramic material or the like that can be fired at a relatively low temperature of, for example, 800 ° C. to 1200 ° C. The notch 2 is formed from the upper surface to one side surface of the body 1, and the strip line 5 is interposed between dielectric layers located in a region where the notch 2 is not formed.
Examples of the ceramic component of the glass-ceramic material forming the dielectric layer of the rectangular laminate 1 include insulating ceramic materials such as cristobalite, quartz, corundum (α-alumina), mullite, cordierite, MgTiO ₃ , and CaTiO _3. , BaTiO _3, a dielectric ceramic material such as TiO _2, Ni-Zn ferrite, magnetic ceramic material such as Mn-Zn ferrite is used, for example, an average particle diameter of 0.5 to 6.0 m, preferably 0. What is ground to 5 to 2.0 μm is used. Note that two or more ceramic materials may be used in combination.
On the other hand, as the glass component of the glass-ceramic material, a crystal phase of cordierite, mullite, anorthite, serdian, spinel, garnite, willemite, dolomite, petalite or a substituted derivative thereof or a crystal phase having a spinel structure is precipitated by firing. well with whatever glass long as, for _{example, B 2 O 3, SiO 2} , Al 2 O 3, ZnO, glass frit containing an alkaline earth oxide. These glass frit have a wide vitrification range, and a sag point is set at, for example, 600 to 800 ° C.
[0019]
The thickness of each dielectric layer forming the rectangular laminate 1 is set, for example, to 20 μm to 300 μm.
[0020]
The strip lines 5 and other circuit wirings 7 provided inside or on the surface of the rectangular laminate 1 are formed of a conductor layer interposed between dielectric layers, a via-hole conductor embedded in the dielectric layer, A connection pad or the like electrically connected to the electronic component element 3 or the like is formed in a formation region of the notch 2, and the material of the strip line 5 and the circuit pattern 7 is the same as that of the dielectric material forming the dielectric layer. Selected in consideration of compatibility. The strip line 5 and the circuit pattern 7 are formed of a conductive material mainly containing an Ag alloy such as Ag, Ag-Pd, Ag-Pt, or a Cu-based, W-based, Mo-based, or Pd-based conductive material. The thickness is set, for example, to 5 to 25 μm. In addition, the strip line 5 described here is a circuit pattern disposed inside the rectangular laminated body 1, the inductance of the pattern itself, the upper surface, the lower surface of the rectangular laminated body 1, and the area where the notch 2 is not formed. And a capacitance between the ground electrode 3 electrically connected to one end of the strip line 5 and the other side of the rectangular laminate 1 on the other side.
Further, as the electronic component element 3 mounted on the surface of the dielectric layer exposed in the formation region of the notch 2, for example, a chip type electronic component such as a capacitor, an inductor, a SAW element, a semiconductor element, or the like is used. By connecting the terminal electrodes of the electronic component element 6 and the connection pads of the circuit wiring 7 described above via a conductive adhesive such as solder, the electronic component element 6 and the strip line 5 are electrically connected. Connected to. When a SAW element or a semiconductor element is used as the electronic component element 6, the electronic component element 6 is hermetically sealed by covering and sealing the periphery with a shield case 4 or the like.
[0021]
In this case, if the height position of the upper surface of the shield case 4 that covers the electronic component element 6 is set to be equal to or lower than the upper surface of the rectangular laminate 1, the high-frequency multilayer circuit board is set. Height can be reduced.
[0022]
According to the high-frequency multilayer circuit board of the present embodiment as described above, the notch 2 is formed from the upper surface of the rectangular laminate 1 to at least one side surface, and the dielectric exposed in the formation region of the notch 2 Since the electronic component element 6 is mounted on the surface of the layer, the strip line 5 and the internal wiring for electrically connecting the strip line 5 to the electronic component element 6 can be arranged under relatively few restrictions. Thus, the degree of freedom in design can be increased without lowering the Q value of the strip line 5, and the overall structure can be reduced in size.
[0023]
Thus, the high-frequency multilayer circuit board described above has an electronic component element on the surface of the dielectric layer exposed on the formation region of the cutout 2 formed on the upper surface of the rectangular laminate 1 formed by laminating a plurality of dielectric layers. 6, a strip line 5 electrically connected to the electronic component element 6 and a ground electrode 3 electrically connected to the strip line 5 on the other side surface of the rectangular laminate 1. Thus, a filter circuit, an oscillation circuit, and the like are configured.
[0024]
Next, a method of manufacturing the rectangular laminate 1 used in the above-described high-frequency multilayer circuit board 10 will be described with reference to FIG.
To manufacture the rectangular laminate 1, a "multiple-piece" method of cutting out a plurality of rectangular laminates 1 from a single mother substrate is employed, and a conventionally known ceramic green sheet laminating method is used. Specifically, first, as shown in FIG. 3A, a large laminate (mother substrate) 20 having a plurality of substrate regions corresponding to the rectangular laminate 1 is prepared. Concave portions 8 corresponding to the notches 2 are continuously formed in the substrate region so as to straddle between adjacent substrate regions.
[0025]
The large laminate 20 is formed by laminating a predetermined number of ceramic green sheets obtained by adding an appropriate organic binder or the like to ceramic raw material powder for forming a dielectric layer of the rectangular laminate 1, Before laminating these ceramic green sheets, a predetermined portion of the uppermost layer or several layers of ceramic green sheets continuing downward from the uppermost layer is punched out with a punch or the like, and through holes are formed in the ceramic green sheets. Thereby, the concave portion 8 is formed. At this time, the recess 8 is formed at a position where the corners of the four substrate regions are in contact with each other.
[0026]
Next, a cutting groove is formed at the boundary 9 between the substrate regions by, for example, a cutter blade or the like, and the large laminated body 20 obtained in the previous step 1 is fired at a high temperature. Thereafter, as shown in FIG. 3B, a plurality of rectangular laminates 1 are cut out by cutting the large laminate 20 along the boundary 9 between the substrate regions.
[0027]
The cutting of the large-sized laminate 20 is performed, for example, by applying pressure from both upper and lower surfaces of the large-sized laminate 20 to divide the large-sized laminate 20 starting from a groove formed at the boundary 9 between the substrate regions (a so-called chocolate break). ), Whereby a plurality of rectangular laminates 1 are manufactured at the same time.
[0028]
When the rectangular laminated body 1 is manufactured by the above-described manufacturing method, since one concave portion may be formed in the large laminated body for four substrate regions, a punch die for forming the concave portion 8 is used. It is relatively large and can be formed at a wide pitch, and the manufacturing equipment for forming the concave portions can be simply configured, so that the production cost of the high-frequency multilayer circuit board can be reduced.
[0029]
Note that the present invention is not limited to the above-described embodiment, and various changes, improvements, and the like can be made without departing from the gist of the present invention.
[0030]
For example, in the above-described embodiment, the shield case 4 is used to cover the electronic component element 6, but the electronic component element 6 may be sealed with a resin material instead.
[0031]
In the above-described embodiment, the rectangular laminate 1 is formed of a ceramic material. However, instead of this, the rectangular laminate is formed using an organic material such as an epoxy resin or a polyimide resin. When a rectangular laminate is formed from such an organic material, it is preferable to adopt a conventionally known dicing method to cut out the rectangular laminate from the large laminate.
[0032]
Further, the coating of the electronic component element is not limited to after the mounting, and for example, a device sealed with a package may be mounted. As a specific package, it is preferable to use a chip size package.
[0033]
【The invention's effect】
According to the high-frequency multilayer circuit board of the present invention, a notch is formed from the upper surface to one side surface of the rectangular laminate, and the electronic component element is mounted on the surface of the dielectric layer exposed in the formation region of the notch. Therefore, the strip line and the internal wiring for electrically connecting the strip line to the electronic component element can be arranged under relatively few restrictions, without lowering the Q value of the strip line. The degree of freedom in design can be increased, and the overall structure can be reduced in size.
[0034]
Further, according to the high frequency multilayer circuit board of the present invention, the notch is provided at the upper corner of the rectangular laminated body, so that the high frequency multilayer circuit board is manufactured by "multi-piece" from the large laminated body. In this case, it is only necessary to form one concave portion in at least two substrate regions in a large-sized laminate, and it is possible to simply maintain manufacturing equipment for forming the concave portion. This makes it possible to reduce the production cost of the high-frequency multilayer circuit board.
[0035]
Further, according to the multilayer circuit board for high frequency of the present invention, the height position of the upper surface of the shield case is set to be equal to or lower than the upper surface of the rectangular laminate, and thereby the multilayer circuit for high frequency is set. It is also possible to reduce the height of the circuit board.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a high-frequency multilayer circuit board according to an embodiment of the present invention.
FIG. 2 is a sectional view of the high-frequency multilayer circuit board of FIG. 1;
3 (a) and 3 (b) are external perspective views for each step for explaining a manufacturing process for manufacturing a rectangular laminated body of the high frequency multilayer circuit board of FIG. 1;
FIG. 4 is an external perspective view of a conventional high-frequency multilayer circuit board.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Rectangular laminated body 1a-1f ... Dielectric layer 2 ... Notch 3 ... Ground electrode 4 ... Shield case 5 ... Strip line 6 ... Electronic component element 7 ... Circuit pattern 8 ... Recess 9 ... Boundary between substrate regions 10 ... Multilayer circuit board 20 for high frequency ... Large laminate

Claims (3)

A notch is formed from the upper surface to at least one side surface of the rectangular laminate formed by laminating a plurality of dielectric layers, and an electronic component element is mounted on the surface of the dielectric layer exposed in a region where the notch is formed. A strip line electrically connected to the electronic component element is formed between the dielectric layers located in the non-formation region of the notch portion, and the upper and lower surfaces of the rectangular laminate and the non-formation region of the notch portion are formed. And a ground electrode provided on the other side surface, and the ground electrode is electrically connected to one end of the strip line on the other side surface. 2. The high-frequency multilayer circuit board according to claim 1, wherein the notch is provided at an upper corner of the rectangular laminate. The electronic component element is covered with a shield case, and a height position of an upper surface of the shield case is set to be equal to or higher than an upper surface of the rectangular laminate. The high-frequency multilayer circuit board according to claim 1 or 2.

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