JP2021036565A - Thin film lc filter and manufacturing method of the same - Google Patents

Abstract

To prevent a damage of a capacity insulation film caused by unevenness in a thin film LC filter having a capacity insulation film formed by an inorganic insulation material.SOLUTION: A thin film LC filter 1 comprises: insulation resin layers 11 and 12; a flat capacity insulation film F, formed by an inorganic insulation material arranged between the insulation resin layers 11 and 12 so that a front surface S3 is contacted to a front surface S1, a front surface S4 is contacted to a front surface S2; a lower capacity electrode 20 embedded into the insulation resin layer 11, and contacted to the front surface S3 of the capacity insulation film D; an upper capacity electrode 21 embedded into the insulation resin layer 12, contacted to the front surface S4 of the capacity insulation film D; and an inductor L provided onto the insulation resin layer 12, and connected to the lower capacity electrode 20 and the upper capacity electrode 21. Thus, since the capacity insulation film D formed by the inorganic insulation material is flat, damages of the capacity insulation film caused by unevenness can be prevented.SELECTED DRAWING: Figure 1

Description

The present invention relates to a thin film LC filter and a method for manufacturing the same, and in particular, includes a capacitive insulating film made of an inorganic insulating material located between the upper capacitance electrode and the lower capacitance electrode, and an insulating resin layer in which the upper capacitance electrode and the lower capacitance electrode are embedded. The present invention relates to a thin film LC filter and a method for manufacturing the same.

As a thin film LC filter including a capacitive insulating film made of an inorganic insulating material and an insulating resin layer in which a lower capacitance electrode is embedded, the thin film LC filter described in Patent Document 1 is known. In the thin film LC filter described in Patent Document 1, a lower electrode portion and an inorganic dielectric film are formed on a base substrate and a flattening film made of ceramic such as alumina, and an upper electrode portion is formed on the inorganic dielectric film. Has a structure. The unevenness formed by the lower electrode portion and the inorganic dielectric film is flattened by the organic insulating layer.

Japanese Unexamined Patent Publication No. 2008-34626

However, in the LC filter described in Patent Document 1, since the lower electrode portion having irregularities is covered with a thin inorganic dielectric film, the stress applied to the inorganic dielectric film is concentrated on the corner portions, and in some cases, the corner portions. Sometimes cracked.

Therefore, an object of the present invention is to prevent damage to the capacitive insulating film due to unevenness in a thin film LC filter provided with a capacitive insulating film made of an inorganic insulating material and a method for manufacturing the same.

The thin film LC filter according to the present invention has a first insulating resin layer having a first surface, a second insulating resin layer having a second surface, and third and fourth surfaces, and has a third surface. Flat capacitive insulation made of an inorganic insulating material arranged between the first insulating resin layer and the second insulating resin layer so that the surface is in contact with the first surface and the fourth surface is in contact with the second surface. The lower capacitance electrode embedded in the film and the first insulating resin layer and in contact with the third surface of the capacitive insulating film, and the upper capacitance embedded in the second insulating resin layer and in contact with the fourth surface of the capacitive insulating film. It is characterized by including an electrode and an inductor pattern provided on the second insulating resin layer and connected to the lower capacitance electrode and the upper capacitance electrode.

According to the present invention, since the capacitive insulating film made of the inorganic insulating material is flat, it is possible to prevent the capacitive insulating film from being damaged due to unevenness.

In the present invention, the first insulating resin layer and the second insulating resin layer may be made of the same material. According to this, it is possible to prevent the occurrence of warpage due to the difference in the coefficient of thermal expansion.

In the present invention, the surface of the lower capacitance electrode in contact with the first insulating resin layer may be roughened. According to this, the adhesion between the lower capacitance electrode and the first insulating resin layer is enhanced. Alternatively, a protective insulating layer made of the same inorganic insulating material as the capacitive insulating film may be provided between the lower capacitance electrode and the first insulating resin layer. According to this, since almost the entire surface of the lower capacitance electrode is covered with the inorganic insulating material, the lower capacitance electrode is protected.

In the present invention, the surface of the upper capacitance electrode in contact with the second insulating resin layer may be roughened. According to this, the adhesion between the upper capacitance electrode and the second insulating resin layer is enhanced.

The thin film LC filter according to the present invention is provided on the third surface of the insulating resin layer in which the inductor pattern is embedded and the fifth surface of the first insulating resin layer located on the side opposite to the first surface, and is provided on the lower capacitance electrode. Even if the connected back surface terminal electrode and the top surface terminal electrode provided on the sixth surface of the third insulating resin layer located on the side opposite to the fifth surface and connected to the inductor pattern are further provided. I do not care. According to this, it is possible to obtain a terminal structure suitable for embedding in a circuit board.

In the present invention, the inductor pattern includes the coil pattern, and the upper capacitance electrode and the lower capacitance electrode may be provided at positions that do not overlap with the inner diameter portion of the coil pattern. According to this, the magnetic field generated by the coil pattern is less likely to interfere with the upper capacitance electrode and the lower capacitance electrode.

In the present invention, the upper capacitance electrode may have a larger film thickness than the lower capacitance electrode. According to this, when the upper capacitance electrode is used as it is as a part of the inductor pattern, the resistance value of the inductor pattern can be reduced.

In the method for manufacturing a thin film LC filter according to the present invention, a laminate having a structure in which both sides of a capacitive insulating film made of an inorganic insulating material is covered with a conductor film is prepared, and a lower capacitive electrode is formed by patterning one of the conductor films. The first step of forming and the first insulating resin layer are prepared, and the laminate is laminated on the first insulating resin layer so that the lower capacitance electrode is embedded in the first insulating resin layer, and then the other conductor. A second step of forming the upper capacitance electrode by patterning the film, a third step of forming a second insulating resin layer on the capacitance insulating film so that the upper capacitance electrode is embedded, and a second insulation. It is characterized by comprising a fourth step of forming the lower capacitance electrode and the inductor pattern connected to the upper capacitance electrode on the resin layer.

According to the present invention, since a capacitive insulating film whose both sides are covered with a conductor film is used, it is not necessary to form a capacitive insulating film on the uneven surface. This makes it possible to prevent damage to the capacitive insulating film due to unevenness. Moreover, since the laminate is laminated on the first insulating resin layer so that the lower capacitance electrode is embedded in the first insulating resin layer after the lower capacitance electrode is formed, the lower capacitance electrode is formed when the lower capacitance electrode is formed. The support substrate used does not remain in the final product.

The method for manufacturing a thin film LC filter according to the present invention may further include a step of roughening the surface of the lower capacitance electrode after the first step and before the second step. According to this, the adhesion between the lower capacitance electrode and the first insulating resin layer is enhanced. Alternatively, after performing the first step and before performing the second step, a step of covering the lower capacitance electrode with a protective insulating layer made of the same inorganic insulating material as the capacitance insulating film may be further provided. According to this, since almost the entire surface of the lower capacitance electrode is covered with the inorganic insulating material, the lower capacitance electrode is protected.

The method for manufacturing a thin film LC filter according to the present invention may further include a step of roughening the surface of the upper capacitance electrode after the second step and before the third step. According to this, the adhesion between the upper capacitance electrode and the second insulating resin layer is enhanced.

The method for manufacturing a thin film LC filter according to the present invention includes a step of forming a via that penetrates the first insulating resin layer and exposes the lower capacitance electrode, and a back surface terminal electrode connected to the lower capacitance electrode via the via. It may be further provided with a step of forming. According to this, it is possible to obtain a terminal structure suitable for embedding in a circuit board.

The method for manufacturing a thin film LC filter according to the present invention further includes a step of forming a via conductor that penetrates a capacitive insulating film and connects one conductor film and the other conductor film before patterning one conductor film. It doesn't matter. According to this, after laminating the laminated body on the first insulating resin layer, the step of forming vias on the capacitive insulating film becomes unnecessary.

As described above, according to the present invention, it is possible to prevent the capacitive insulating film from being damaged due to unevenness in the thin film LC filter provided with the capacitive insulating film made of an inorganic insulating material and the method for manufacturing the thin film LC filter.

FIG. 1 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 1 according to the first embodiment of the present invention. FIG. 2 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 3 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 4 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 5 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 6 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 7 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 8 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 9 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 10 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 11 is a process diagram for explaining a method for manufacturing the thin film LC filter 1. FIG. 12 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 2 according to the second embodiment of the present invention. FIG. 13 is a process diagram for explaining a method for manufacturing the thin film LC filter 2. FIG. 14 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 3 according to the third embodiment of the present invention. FIG. 15 is a process diagram for explaining a method for manufacturing the thin film LC filter 3. FIG. 16 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 4 according to the fourth embodiment of the present invention. FIG. 17 is a process diagram for explaining a method for manufacturing the thin film LC filter 4. FIG. 18 is a process diagram for explaining a method for manufacturing the thin film LC filter 4. FIG. 19 is a process diagram for explaining a method for manufacturing the thin film LC filter 4. FIG. 20 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 5 according to the fifth embodiment of the present invention. FIG. 21 is a process diagram for explaining a method for manufacturing the thin film LC filter 5. FIG. 22 is a process diagram for explaining a method for manufacturing the thin film LC filter 5. FIG. 23 is a process diagram for explaining a method for manufacturing the thin film LC filter 5.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 1 according to the first embodiment of the present invention.

As shown in FIG. 1, the thin film LC filter 1 according to the first embodiment has a flat capacity made of an insulating resin layer 11 to 13 and an inorganic insulating material arranged between the insulating resin layer 11 and the insulating resin layer 12. It includes an insulating film D and wiring layers M1 to M5 and MM. The insulating resin layers 11 to 13 are made of a material in which a filler is added to the resin, and may be made of the same material or different materials from each other. If the same materials are used as the materials constituting the insulating resin layers 11 to 13, it is possible to prevent the occurrence of warpage due to the difference in the coefficient of thermal expansion. The insulating resin layer 13 has a three-layer structure composed of insulating resin layers 13a to 13c.

The capacitive insulating film D has a surface S3 and a surface S4 located on the opposite side thereof, and these surfaces S3 and S4 are all flat. The capacitive insulating film D is arranged between the insulating resin layer 11 and the insulating resin layer 12 so that the surface S3 is in contact with the surface S1 of the insulating resin layer 11 and the surface S4 is in contact with the surface S2 of the insulating resin layer 12. Will be done. The capacitive insulating film D is a continuous film that is not patterned except for a portion through which the via conductor 30 penetrates. The inorganic insulating material constituting the capacitive insulating film D includes a group consisting of alumina, aluminum nitride, silica, silicon nitride, tantalum oxide, niobium oxide, titanium oxide, strontium titanate, barium titanate titanate, and lead zirconate titanate. It preferably contains at least one selected dielectric material.

A lower capacitive electrode 20 belonging to the wiring layer M1 is formed on the surface S3 of the capacitive insulating film D. The lower capacitance electrode 20 is embedded in the insulating resin layer 11. Further, an upper capacitance electrode 21 belonging to the wiring layer MM is formed on the surface S4 of the capacitance insulating film D. The upper capacitance electrode 21 is embedded in the insulating resin layer 12. The lower capacitance electrode 20 and the upper capacitance electrode 21 face each other via the capacitance insulating film D, and this portion functions as the capacitor C. The film thickness of the lower capacitance electrode 20 and the upper capacitance electrode 21 may be the same as each other, but if the film thickness of the upper capacitance electrode 21 is made larger than the film thickness of the lower capacitance electrode 20, the upper capacitance electrode 21 remains as it is. When used as a part of the inductor pattern, the resistance value of the inductor pattern can be reduced.

The wiring layers M2 to M5 are wiring layers located on the surfaces of the insulating resin layers 12, 13a, 13b, and 13c, respectively. Conductor patterns 22 to 25 are formed on the wiring layers M2 to M5, respectively. The conductor pattern 22 is connected to the lower capacitance electrode 20 via a via conductor 30 provided so as to penetrate the insulating resin layer 12 and the capacitance insulating film D, and is provided so as to penetrate the insulating resin layer 12. It is connected to the upper capacitance electrode 21 via a conductor 31. Further, the conductor pattern 23 is connected to the conductor pattern 22 via a via conductor 32 provided through the insulating resin layer 13a, and the conductor pattern 24 is connected to the conductor pattern 22 via a via conductor 33 provided through the insulating resin layer 13b. The conductor pattern 25 is connected to the conductor pattern 23, and the conductor pattern 25 is connected to the conductor pattern 24 via a via conductor 34 provided so as to penetrate the insulating resin layer 13c. The conductor patterns 22 to 25 form an inductor pattern, and this portion functions as the inductor L.

The inductor pattern includes a coil pattern wound in a helical shape, and the inner diameter portion A and the capacitor C are arranged at positions where they do not overlap each other in a plan view. As a result, the interference between the magnetic field generated by the current flowing through the coil pattern and the upper capacitance electrode 21 and the lower capacitance electrode 20 is reduced, so that it is possible to suppress a decrease in inductance.

The conductor pattern 25 is exposed from the surface S6 of the insulating resin layer 13c, and is used as a terminal electrode of the thin film LC filter 1 according to the present embodiment. Therefore, if the thin film LC filter 1 shown in FIG. 1 is turned upside down, it can be surface-mounted on a circuit board using solder or the like.

As described above, in the thin film LC filter 1 according to the present embodiment, the capacitive insulating film D made of the inorganic insulating material is flat. Therefore, unlike a general thin film LC filter in which a capacitive insulating film is formed on the uneven surface, a strong stress is not applied to a specific portion of the capacitive insulating film D, and cracks and the like are unlikely to occur in the capacitive insulating film D. Further, since the capacitive insulating film D is a continuous film, the amount of patterning of the capacitive insulating film D can be minimized.

Next, a method for manufacturing the thin film LC filter 1 according to the present embodiment will be described.

2 to 11 are process diagrams for explaining a method for manufacturing the thin film LC filter 1.

First, as shown in FIG. 2, a capacitive insulating film D having conductor films formed on both sides is prepared. One of the conductor films is the wiring layer M1 and the other is the wiring layer MM. As a method for producing such a laminate, for example, a copper foil or a nickel foil constituting the wiring layer M1 is prepared, a capacitive insulating film D is formed on the surface thereof by a CVD method or the like, and the capacitance is further formed. A method of forming the wiring layer MM on the surface of the insulating film D by a plating method or the like can be mentioned. The laminate thus produced is mounted on the surface of the support substrate 41. At this time, the laminate is mounted on the surface of the support substrate 41 so that the wiring layer MM faces the support substrate 41 and the wiring layer M1 is exposed.

In this state, as shown in FIG. 3, the lower capacitance electrode 20 is formed by patterning the wiring layer M1. The surface S3 of the capacitive insulating film D is exposed at the portion where the wiring layer M1 is removed. Then, the surface of the lower capacitance electrode 20 is roughened with an acid or the like.

Next, as shown in FIG. 4, the insulating resin layer 11 formed on the surface of the support substrate 42 is prepared, and the wiring layer M1 is provided so that the surface S1 of the insulating resin layer 11 and the surface S3 of the capacitive insulating film D are in contact with each other. The laminate composed of the capacitive insulating film D and the wiring layer MM is inverted and laminated. After that, the support substrate 41 is peeled off. As a result, as shown in FIG. 5, the surface S1 of the insulating resin layer 11 and the surface S3 of the capacitive insulating film D form a flat coplanar surface, and the lower capacitive electrode 20 is embedded in the insulating resin layer 11. Become.

In this state, as shown in FIG. 6, the upper capacitance electrode 21 is formed by patterning the wiring layer MM. The surface S4 of the capacitive insulating film D is exposed at the portion where the wiring layer MM is removed. Then, the surface of the upper capacitance electrode 21 is roughened with an acid or the like.

Next, as shown in FIG. 7, the insulating resin layer 12 is prepared, and the insulating resin layer 12 is laminated so that the surface S2 of the insulating resin layer 12 and the surface S4 of the capacitive insulating film D are in contact with each other. As a result, the surface S2 of the insulating resin layer 12 and the surface S4 of the capacitive insulating film D form a flat coplanar surface, and the upper capacitive electrode 21 is embedded in the insulating resin layer 12. After that, vias 30a and 31a are formed by using known methods such as laser processing and blasting. The via 30a penetrates the insulating resin layer 12 and the capacitance insulating film D, and the lower capacitance electrode 20 is exposed on the bottom surface. Further, the via 31a penetrates the insulating resin layer 12, and the upper capacitance electrode 21 is exposed on the bottom surface.

Next, as shown in FIG. 8, by performing electroless plating and electroplating in this order, a conductive material made of copper or the like is formed inside the vias 30a and 31a and on the surface S6 of the insulating resin layer 12. As a result, via conductors 30 and 31 are formed inside the vias 30a and 31a, respectively, and a wiring layer M2 is formed on the surface S7 of the insulating resin layer 12. Then, the conductor pattern 22 is formed by patterning the wiring layer M2.

Next, as shown in FIG. 9, the via conductor 32 and the wiring layer M3 are formed by laminating the insulating resin layer 13a, forming vias, and forming a conductive material by electroless plating and electrolytic plating to form the wiring layer M3. The conductor pattern 23 is formed by patterning. Similarly, as shown in FIG. 10, the via conductor 33 and the wiring layer M4 are formed by laminating the insulating resin layer 13b, forming vias, and forming a conductive material by electroless plating and electrolytic plating to form the wiring layer. The conductor pattern 24 is formed by patterning M4. Further, as shown in FIG. 11, the via conductor 34 and the wiring layer M5 are formed by laminating the insulating resin layer 13c, forming vias, and forming a conductive material by electroless plating and electrolytic plating to form the wiring layer M5. The conductor pattern 25 is formed by patterning.

Then, after the support substrate 42 is peeled off, the substrate is divided along the dicing line 43 shown in FIG. 11, and the thin film LC filter 1 shown in FIG. 1 is completed.

As described above, in the present embodiment, the capacitive insulating film D having the conductor films formed on both sides is prepared, the lower capacitive electrode 20 is formed by patterning, and then the insulating resin layer formed on another support substrate 42. Since the capacitive insulating film D is laminated on 11, it is possible to eliminate the step of forming the capacitive insulating film on the uneven surface. Moreover, in the process shown in FIG. 4, since the laminated body is turned upside down and laminated on the insulating resin layer 11, the support substrate 41 or the like used when forming the lower capacitance electrode 20 may remain in the final product. Absent. Further, since the lower capacitance electrode 20 and the upper capacitance electrode 21 are roughened, the adhesion between the lower capacitance electrode 20 and the insulating resin layer 11 and the adhesion between the upper capacitance electrode 21 and the insulating resin layer 12 can be improved. ..

<Second embodiment>
FIG. 12 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 2 according to the second embodiment of the present invention.

As shown in FIG. 12, in the thin film LC filter 2 according to the second embodiment, a protective insulating layer 14 made of the same inorganic insulating material as the capacitive insulating film D is provided between the lower capacitance electrode 20 and the insulating resin layer 11. In that respect, it is different from the thin film LC filter 1 according to the first embodiment shown in FIG. Since the other basic configurations are the same as those of the thin film LC filter 1 according to the first embodiment, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

In the thin film LC filter 2 according to the present embodiment, since almost the entire surface of the lower capacitance electrode 20 is covered with the inorganic insulating material, the lower capacitance electrode 20 is more reliably protected. Here, the protective insulating layer 14 is formed on an uneven surface, but even if a crack occurs in the protective insulating layer 14, the characteristics of the capacitor C are not affected.

When the thin film LC filter 2 according to the present embodiment is manufactured, the surface of the lower capacitance electrode 20 is protected by a CVD method or the like as shown in FIG. 13 after performing the steps described with reference to FIGS. 2 and 3. The insulating layer 14 may be formed. After that, the thin film LC filter 2 according to the present embodiment is completed by sequentially performing the steps described with reference to FIGS. 4 to 11.

<Third embodiment>
FIG. 14 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 3 according to the third embodiment of the present invention.

As shown in FIG. 14, the thin film LC filter 3 according to the third embodiment has a via conductor 35 provided through the insulating resin layer 11 and a back surface connected to the lower capacitance electrode 20 via the via conductor 35. It differs from the thin film LC filter 1 according to the first embodiment shown in FIG. 1 in that the terminal electrode 26 is provided. Since the other basic configurations are the same as those of the thin film LC filter 1 according to the first embodiment, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

Since the thin film LC filter 3 according to the present embodiment is provided with the back surface terminal electrode 26 in addition to the conductor pattern 25 constituting the top surface terminal electrode, the thin film LC filter 3 can be connected from both sides even when embedded in the circuit board. It becomes possible to take.

When the thin film LC filter 3 according to the present embodiment is produced, after performing the steps described with reference to FIGS. 2 to 11, as shown in FIG. 15, insulation is performed using a known method such as laser processing or blasting. A via 35a is formed on the resin layer 11. The via 35a penetrates the insulating resin layer 11 and the lower capacitance electrode 20 is exposed on the bottom surface. After that, by performing electroless plating and electrolytic plating in this order, a via conductor 35 is formed inside the via 35a, and a conductive material made of copper or the like is formed on the surface S5 of the insulating resin layer 11, and then patterning is performed. By doing so, the back surface terminal electrode 26 is formed. As a result, the thin film LC filter 3 according to the present embodiment is completed.

<Fourth Embodiment>
FIG. 16 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 4 according to the fourth embodiment of the present invention.

As shown in FIG. 16, in the thin film LC filter 4 according to the fourth embodiment, the conductor pattern 21a is provided in the wiring layer MM, and the conductor pattern 21a passes through the via conductors 36 and 37, respectively, and the lower capacitance electrode 20 and the conductor pattern. It differs from the thin film LC filter 1 according to the first embodiment shown in FIG. 1 in that it is connected to 22. Since the other basic configurations are the same as those of the thin film LC filter 1 according to the first embodiment, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

In the thin film LC filter 4 according to the present embodiment, the lower capacitance electrode 20 is connected to the conductor pattern 21a located in the wiring layer MM. Therefore, the step of forming vias on the capacitive insulating film D after the laminated body is turned upside down and laminated on the insulating resin layer 11 becomes unnecessary.

When the thin film LC filter 4 according to the present embodiment is produced, as shown in FIG. 17, a capacitance insulating film D is formed on the surface of the wiring layer MM, and then the capacitance insulating film D is patterned to form the via 36a. When the wiring layer M1 is formed on the surface S3 of the capacitive insulating film D by plating in this state, the via 36a is filled with the via conductor 36 as shown in FIG. 18, and the wiring layer M1 passes through the via conductor 36. And the wiring layer MM are short-circuited. Then, as shown in FIG. 19, a laminate composed of the wiring layer M1, the capacitive insulating film D, and the wiring layer MM is mounted on the surface of the support substrate 41. At this time, the laminate is mounted on the surface of the support substrate 41 so that the wiring layer MM faces the support substrate 41 and the wiring layer M1 is exposed.

After that, the thin film LC filter 4 according to the present embodiment is completed by performing the steps described with reference to FIGS. 4 to 11.

<Fifth Embodiment>
FIG. 20 is a schematic cross-sectional view for explaining the structure of the thin film LC filter 5 according to the fifth embodiment of the present invention.

As shown in FIG. 20, in the thin film LC filter 5 according to the fifth embodiment, the end portion of the capacitive insulating film D is removed, whereby the insulating resin layer 11 and the insulating resin layer 12 come into contact with each other at the end portion. In that respect, it differs from the thin film LC filter 1 according to the first embodiment shown in FIG. Since the other basic configurations are the same as those of the thin film LC filter 1 according to the first embodiment, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

Since the capacitive insulating film D is not exposed to the outside in the thin film LC filter 5 according to the present embodiment, it is possible to prevent the capacitive insulating film D from being damaged or deteriorated.

When the thin film LC filter 5 according to the present embodiment is produced, after performing the steps described with reference to FIGS. 2 and 3, the end portion of the capacitive insulating film D is removed by patterning as shown in FIG. As shown in 22, the laminated body composed of the wiring layer M1, the capacitive insulating film D, and the wiring layer MM is inverted and laminated so that the surface S1 of the insulating resin layer 11 and the surface S3 of the capacitive insulating film D are in contact with each other. Then, as shown in FIG. 23, the support substrate 41 is peeled off. After that, the thin film LC filter 5 according to the present embodiment is completed by sequentially performing the steps described with reference to FIGS. 6 to 11.

Further, if the thin film LC filter 5 according to the present embodiment is cut along the broken line B shown in FIG. 20, the same structure as that of the thin film LC filter 1 shown in FIG. 1 can be obtained.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention, and these are also the present invention. Needless to say, it is included in the range.

1 to 5 Thin LC filters 11 to 13, 13a, 13b, 13c Insulating resin layer 14 Protective insulating layer 20 Lower capacitance electrode 21 Upper capacitance electrode 21a, 22 to 25 Conductor pattern 26 Backside terminal electrodes 30 to 37 Via conductors 30a, 31a, 35a, 36a Vias 41, 42 Support substrate 43 Dying line A Inner diameter C Capacitor D Capacitor insulation film L Inductor M1 to M5, MM Wiring layer S1 to S7 Surface

Claims (14)

A first insulating resin layer having a first surface and
A second insulating resin layer having a second surface and
The first insulating resin layer and the first surface are provided so that the third and fourth surfaces are in contact with the first surface and the fourth surface is in contact with the second surface. A flat capacitive insulating film made of an inorganic insulating material arranged between the insulating resin layers 2 and
A lower capacitive electrode embedded in the first insulating resin layer and in contact with the third surface of the capacitive insulating film.
An upper capacitive electrode embedded in the second insulating resin layer and in contact with the fourth surface of the capacitive insulating film.
A thin film LC filter provided on the second insulating resin layer and comprising an inductor pattern connected to the lower capacitance electrode and the upper capacitance electrode. The LC filter according to claim 1, wherein the first insulating resin layer and the second insulating resin layer are made of the same material. The LC filter according to claim 1 or 2, wherein the surface of the lower capacitance electrode in contact with the first insulating resin layer is roughened. The LC filter according to claim 1 or 2, wherein a protective insulating layer made of the same inorganic insulating material as the capacitive insulating film is provided between the lower capacitance electrode and the first insulating resin layer. .. The LC filter according to any one of claims 1 to 4, wherein the surface of the upper capacitance electrode in contact with the second insulating resin layer is roughened. A third insulating resin layer in which the inductor pattern is embedded and
A back surface terminal electrode provided on the fifth surface of the first insulating resin layer located on the side opposite to the first surface and connected to the lower capacitance electrode, and a back surface terminal electrode.
The claim is characterized in that a top terminal electrode provided on the sixth surface of the third insulating resin layer located on the side opposite to the fifth surface and connected to the inductor pattern is further provided. The LC filter according to any one of 1 to 5. The inductor pattern includes a coil pattern.
The LC filter according to any one of claims 1 to 6, wherein the upper capacitance electrode and the lower capacitance electrode are provided at positions that do not overlap with the inner diameter portion of the coil pattern. The LC filter according to any one of claims 1 to 7, wherein the upper capacitance electrode has a larger film thickness than the lower capacitance electrode. A first step of preparing a laminate having a structure in which both sides of a capacitive insulating film made of an inorganic insulating material are covered with a conductor film and patterning one of the conductor films to form a lower capacitive electrode.
A first insulating resin layer is prepared, the laminate is laminated on the first insulating resin layer so that the lower capacitance electrode is embedded in the first insulating resin layer, and then the other conductor film is patterned. The second step of forming the upper capacitance electrode by
A third step of forming a second insulating resin layer on the capacitive insulating film so that the upper capacitive electrode is embedded, and
A method for manufacturing a thin film LC filter, which comprises a fourth step of forming an inductor pattern connected to the lower capacitance electrode and the upper capacitance electrode on the second insulating resin layer. The production of the LC filter according to claim 9, further comprising a step of roughening the surface of the lower capacitance electrode after the first step and before the second step. Method. After the first step and before the second step, a step of covering the lower capacitance electrode with a protective insulating layer made of the same inorganic insulating material as the capacitance insulating film is further provided. The method for manufacturing an LC filter according to claim 9. Any one of claims 9 to 11, further comprising a step of roughening the surface of the upper capacitance electrode after the second step is performed and before the third step is performed. The method for manufacturing an LC filter according to the above. A step of forming a via that penetrates the first insulating resin layer and exposes the lower capacitance electrode.
The method for manufacturing an LC filter according to any one of claims 9 to 12, further comprising a step of forming a back surface terminal electrode connected to the lower capacitance electrode via the via. 9. The present invention further comprises a step of forming a via conductor that penetrates the capacitive insulating film and connects the one conductor film and the other conductor film before patterning the one conductor film. The method for manufacturing an LC filter according to any one of 13 to 13.

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